description stringlengths 2.98k 3.35M | abstract stringlengths 94 10.6k | cpc int64 0 8 |
|---|---|---|
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is related to U.S. Provisional Patent Application 60/447,733 filed Feb. 19, 2003, and the complete contents of that application is herein incorporated by reference.
DESCRIPTION
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention generally relates to fiber formation by electrospinning and, more particularly, to a new technique for the formation of polymeric fiber interconnections in very small (e.g., microscale or nanoscale) systems.
[0004] 2. Background Description
[0005] Polymer fibers form the basis of a wide variety of industries ranging from breathable, weather-resistant, and bulletproof garments to telecommunications, structural engineering, and medicine. Polymer fibers are conventionally created by extruding a polymer melt through a spinneret and subsequently drawing the fibers as they coagulate. However, it is difficult to produce submicron diameter fibers using this conventional process and many emerging opportunities exist for high performance nanoscale materials and devices.
[0006] The recent focus on nanoscale engineering has revived interest in a radically different fiber formation technology known as electrospinning, wherein a polymer fiber is drawn from a solution using electrostatic instead of mechanical forces. The basic advantage of the electrospinning fiber formation process is that extremely small diameter, nanoscale fibers can be produced from a wide variety of polymer solutions (see, for example, Kenawy et al., Biomaterials 24:907 (2003); Deitzel et al, Polymer, 42:8163 (2001); and Reneker et al, Nanotechnology 7:216 (2000)). The theoretical model for the electrospinning process has evolved over time and the fiber formation mechanisms have been described in several recent articles (se, for example, Deitzel et al., Polymer 42:261 (2001); Yarin et al., J. App. Phys. 90:4836 (2001); and Shin et al., Polymer, 42:9955 (2001)). Typically, an electrospinning apparatus consists of a hypodermic syringe or needle filled with a polymer solution and placed at a high (approximately 15 kV) potential with respect to a ground plane. The sharp tip of the needle concentrates the electrostatic force and fibers emerge from the tip of a Taylor cone formed at the surface of the solution through a competition between electrostatic forces and surface tension. The fibers are collected at the counter electrode and typical electrospun structures consist of a nonwoven mat of fine fibers.
SUMMARY OF THE INVENTION
[0007] It is therefore an object of the present invention to provide a new method of making polymeric microfiber interconnections which does not require complex chemistry or mechanical devices.
[0008] The physical laws of electrostatics that drive the conventional electrospinning fiber formation process are quite general. We demonstrate herein that the entire process can be scaled to achieve directed nanoscale polymer fiber growth on the surface of a microchip without the need for high voltage, pumps, or needles. In fact, the fiber formation process appears to be favored at reduced dimensions due to electric field concentration effects. Thus, it will be possible, using this invention, to produce controlled nanoscale polymer fiber structures and interconnections directly on the surface of a chip for numerous applications including, without limitation, intrachip optical interconnections for the computer industry, chip-scale biocompatible fiber-based scaffolds, and highly sensitive microsensors.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] The foregoing and other objects, aspects and advantages will be better understood from the following detailed description of a preferred embodiment of the invention with reference to the drawings, in which:
[0010] [0010]FIGS. 1 a - b are schematic side and top view diagrams, respectively, illustrating fiber formation between neutral droplets on oppositely charged electrodes; and
[0011] [0011]FIG. 1 c is an illustration of fiber formation between oppositely charged droplets applied to an insulating surface using electrospray ionization.
DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT OF THE INVENTION
[0012] The invention of forming polymer fiber interconnections is best understood by two related embodiments, both of which have been demonstrated experimentally. In the first method, illustrated in FIGS. 1 a and 1 b , a polymer 10 was dissolved in a solvent and neutral, microscale droplets were airbrushed onto the surface of an interdigitated metal electrode 12 on a glass substrate 14 . A potential difference was applied between the electrodes and fibers 16 were observed to form between droplets on alternating electrodes. In the second method, illustrated in FIG. 1 c , positively and negatively charged droplets 18 and 20 , respectively, were alternately sprayed onto an insulating substrate using electrospray ionization. This can be done by a number of means as discussed, for example, in Dole, J. Chem. Phys. 49:2240 (1968); Iribarne et al., J. Chem. Phys. 64:2287 (1976); and Yamashita et al. J. Phys. Chem. 88:4451 (1984). In the experiments discussed herein, the change in droplet polarity was achieved by switching the polarity of the high voltage power supply used to drive the electrospray process. In this case, nanoscale fibers were observed to form spontaneously between oppositely charged droplets without the need for the application of an external potential.
[0013] Atomic force microscopy (AFM) images were made of a typical sub-micron diameter carboxymethylcellulose (CMC) fiber produced using the method of the first embodiment described above. In the experiment, two metal electrodes separated by 15 μm on the surface of a glass substrate. The CMC was first dissolved in a water/methanol solution at a concentration of 0.2 wt %. The solution was then airbrushed onto the electrode in the form of microscale droplets. The concentration of the polymer in the droplets on the surface is expected to be greater than the original solution concentration due to solvent evaporation. A potential difference of 6 V was immediately applied between the interdigitated metal electrodes before complete evaporation of the liquid solvent. Due to the small spacing between the electrodes, this voltage difference produces an electric field magnitude on the order of 4 kV/cm, which is typical of the fields used in the conventional, macroscale electrospinning process. AFM images were obtained and compared to images from control samples produced in an identical process, but without an applied voltage. While numerous fibers were observed on the samples to which a voltage had been applied, no fibers could be found on the samples for which no external voltage was applied. Once established and upon removal of the potential difference, the dry, solvent-free polymer fibers were found to be mechanically stable and remained intact on the surface of the micro electrode.
[0014] Similar experiments were conducted and fibers were made using the method of the second embodiment set forth above. Scanning Electron Microscopy (SEM) images were obtained showing a single 100 nm diameter CMC fiber connecting to oppositely charged droplets each of which were approximately 2 μm in diameter. In addition, SEM images showed a single droplet with at least six individual fibers emerging from various locations around the circumference and connecting two oppositely charged droplets. In these experiments, CMC was dissolved in a water/methanol solution at a concentration of 0.01 wt %. Positively charged droplets were electrosprayed onto the polycarbonate substrate by applying a positive potential of 7.5 kV to the electrospray needle with respect to a ground plane established behind the substrate. Negatively charged droplets were applied to the polycarbonate substrate in the same manor by switching the power supply polarity. SEM and AFM images were obtained and compared to samples coated with both neutral droplets from airbrushing and single polarity droplets from electrospray. Fibers were only observed on the polycarbonate substrates coated with oppositely charged droplets.
[0015] The results observed essentially provide for polymer electrospinning at microscopic dimensions and can allow for the production of nanoscale polymer fibers, interconnections, and scaffolds on the surface of, for example, a microchip. The fiber formation process is very simple and fast, does not require any special materials, chemistry, or equipment, and can be applied to a wide variety of materials such as conducting, electroactive, photonic, and biocompatible polymers. The images observed by SEM exhibit specific microscale features that are characteristic of an electric field driven fiber formation process. For example, each nanoscale fiber emerges from a small conical structure protruding from the surface of the droplet, which appears to be analogous to a Taylor cone. The cones are formed from a competition between the electrostatic forces and surface tension at a time before the solvent has completely evaporated. As the solvent continues to evaporate the viscosity of the droplet increases, preserving the electric field induced microstructure which was observed.
[0016] It should be understood that the process is applicable to a number of different polymers and would be readily applicable to materials such as conducting and biocompatible polymers (such as, for example, polyaniline or polylacticacid) and even polymer composites (such as, for example, polymers containing carbon nanotubes or metallic nanoparticles) and mixtures (such as, for example, polymer blends or polymers combined with inorganics). In either embodiment, the positively and negatively charged drops could include the same or different polymers, as well as mixtures of polymers. A number of solvents could be used within the practice of the invention including, for example, water, organic solvents, alcohols or acids. The chief requirement is that the polymer is dissolved in a liquid solvent. In the practice of the invention, the solution of polymer and solvent is applied to material(s) or device(s) to be connected. Example materials or devices include the components or devices in an electrical circuit, microchip, biochip, or other organic or inorganic materials. The volume of the drops can vary between picoliters and microliters, and will depend on the application and the length of fiber to be produced. Likewise, the spacing between the positively and negatively charged droplets can vary depending on the application, and will typically be between 1 micron and 50 microns. The solution application method can vary and would depend on the nature of the components to be connected. Examples of application methods include airbrushing, electrospraying, dipping, spinning, inkjet technology and direct application using a device such as a syringe.
[0017] As noted above, an electric field is created between the components to be connected. The electric field could be created directly by application of a potential difference as in the first embodiment. In this embodiment, the magnitude of the field can vary depending on the application, but will typically be between 100V/cm and 10,000V/cm. Also, as in the second embodiment, the electric field can be present naturally if the solutions to be connected are oppositely charged. Polymer fiber interconnections will form between the components of opposite polarity when the electric field magnitude reaches a critical value. The critical magnitude of the electric filed will differ for different polymers, solvents, and solution concentrations. The interconnections can be formed between two or more solutions of opposite polarity or between one solution and another component of opposite polarity.
[0018] Potential applications include the creation of interconnections on microchips and biochips, the formation of sensors based on polymer nanowires and the formation of neural networks. The invention may also be used in the field of medicine in, for example, nerve generation using biocompatible polymers for the interconnections. Depending on the application, the polymer droplets could adhere to different portions of a substrate (e.g., to different components on the substrate) or to different substrates with one or more fibers interconnecting the droplets (thus interconnecting the two substrates or the two components on a substrate, for example). Alternatively, for some applications, it may be desirable to remove the fibers after fiber formation, and use them in an application of interest.
[0019] While the invention has been described in terms of its preferred embodiment, those skilled in the art will recognize that the invention can be practiced with modification within the spirit and scope of the appended claims. | Polymer fiber interconnects are produced between microscale features on substrate using only electrostatic forces. In one embodiment, electric field driven directed growth of fibers is achieved between microscale droplets of a concentrated polymer solution deposited on a substrate associated with a capacitor, such as an interdigitated capacitor. After depositing the droplets, the droplets on or near the positive electrode become positively charged and the droplets on or near the negative electode become negatively charged. Fibers form between the positively and negatively charged droplets due to electrostatic forces. In a second embodiment, positively charged and negatively droplets are created by electrospraying or by other means, and the fibers spontaneously form between droplets of opposite polarity. The process is similar to conventional electrospinning, but is achieved on a micrscopic scale and utilizes significantly lower driving potentials. | 3 |
FIELD OF THE INVENTION AND RELATED ART STATEMENT
The present invention relates to a control apparatus and a proportional solenoid valve control circuit for boom-equipped working implements.
Working implements comprising a boom assembly liftably pivoted to a vehicle body and working means pivotably connected to the forward end of the boom assembly include a tractor-attached front loader and various other implements.
The tractor-attached front loader comprises a pair of opposite booms liftably pivoted to the body of the tractor, and a bucket pivotably connected to the forward end of each boom. A hydraulic circuit for a boom cylinder and a bucket cylinder for operating the boom where the bucket has solenoid valves in corresponding relation to these cylinders for controlling the upward or downward movement of the boom and the rotation of the bucket in a scooping or dumping direction.
The control system for such a working implement generally has an operating lever which is moved forward or rearward or sideward to operate a switch, which in turn energizes or deenergizes the corresponding solenoid valve.
However, the conventional on-off drive type control system, which merely opens or closes the solenoid valve, is not adapted to control the flow of the working fluid, so that the cylinder is operated at a constant speed at all times and is not operable at a very low speed. Accordingly, the system has the drawback of necessitating great skill for operating the working implement which requires a delicate movement.
For example, when earth or sand is to be transported by the front loader after scooping with the bucket and if the booms are merely raised, then the booms incline the bucket with its front end raised, permitting the contents of the bucket to spill rearward. To avoid this, the bucket is rotated very slowly with the rise of the booms toward the dumping direction to cause the bucket to assume a corrected posture with its opening positioned horizontally.
Further when earth or sand is to be scooped up again after dumping the contents of the bucket at its raised position by lowering the booms, the bottom of the bucket must be placed on the ground horizontally. Therefore in this case also, the bottom is correctly positioned horizontally by rotating the bucket slowly when the booms are lowered.
Additionally, there arises a need to raise or lower the booms very slowly, for example, to diminish impact upon stopping.
Thus, the operation of the front loader requires low-speed movement of the booms and the bucket, whereas with the conventional control system of the on-off type incorporating switches, the solenoid valve is not adapted for flow control, consequently necessitating great skill for the operation of the loader.
Further, the solenoid valves are conventionally operated merely in an operative relation with the manipulation of the operating lever, so that the control system is not adapted to preset the posture of the bucket and to bring the bucket into the preset posture when the booms are raised or lowered.
On the other hand, control circuits for proportional solenoid valves for use in such control systems include one which has a servo mechanism. The servo mechanism is so operated as to vary the resistance value of a variable resistor in accordance with the amount of manipulation of the operating lever, whereby an energizing current proportional to the movement of the manipulating lever is passed through the valve for controlling the flow of working fluid.
Nevertheless, the control circuit, which necessitates the servo mechanism or the like, has the drawbacks of being very complex in construction, cumbersome to make and liable to malfunctions.
OBJECTS AND SUMMARY OF THE INVENTION
The present invention has been accomplished in order to solve the foregoing problems heretofore encountered.
More specifically, a first object of the present invention is to provide a control apparatus comprising operating means, a control system for a boom and a control system for a working device. Each of the systems has a proportional solenoid valve which is operable in a specified direction in proportion to the amount of manipulation of the operating means when the operating means is manipulated in the specified direction to move the boom or the working device at a speed corresponding to the amount of manipulation.
A second object of the invention is to provide a control apparatus of the type stated wherein the proportional solenoid valve is easily and reliably operable in a proportional relation with the manipulation of the operating means by processing electric signals instead of the servo mechanism or the like conventionally used.
To fulfill these objects, the present invention provides a control apparatus comprising a boom control system and a working device control system each having a proportional solenoid valve. Each of the systems comprises instruction means for producing an instruction signal in accordance with the amount of manipulation of operating means, discriminating means for discriminating the direction of operation of the proportional solenoid valve from the instruction signal, means for generating a specified reference signal, comparison means for comparing the instruction signal with the reference signal to obtain a pulse signal having a pulse width in proportion to the amount of manipulation of the operating means, and drive means for converting the pulse signal from the comparison means into an electric current to drive the proportional solenoid valve in the direction discriminated by the discriminating means.
A third object of the present invention is to provide a control apparatus of the type described wherein the boom control system is proportionally controllable and the posture of the working device is presettable by the working device control system to render the working device automatically controllable to the contemplated posture smoothly when the boom is raised or lowered.
To fulfill this object, the working device control system of the present invention comprises a sensor for detecting the rotated posture of the working device, means for setting the desired posture of the working device, deviation detecting means for determining the difference between a signal from the posture sensor and a signal from the setting means to produce a deviation signal, means for discriminating from the deviation signal from the direction in which the working device is to be rotated, comparator means for comparing the deviation signal with the reference signal from the reference signal generating means to produce a pulse signal of a pulse width in proportion to the deviation signal, and drive means for converting the pulse signal from the comparator means into an electric current to drive the proportional solenoid valve in the direction of rotation of the working device determined by the discriminating means.
A fourth object of the present invention is to provide a control circuit which is most suitable for controlling the proportional solenoid valve included in the type of control apparatus for the working implement described.
For this purpose, the invention provides a control circuit comprising instruction means for producing an instruction signal in accordance with the amount of manipulation of operating means, discriminating means for discriminating the direction of operation of the proportional solenoid valve from the instruction signal, means for generating a specified reference signal, comparison means for comparing the instruction signal with the reference signal to obtain a pulse signal having a pulse width in proportion to the amount of manipulation of the operating means, and drive means for converting the pulse signal from the comparison means into an electric current to drive the proportional solenoid valve in the direction discriminated by the discriminating means.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1 to 15 show a first embodiment of the present invention;
FIG. 1 is a side elevation showing a tractor and a front loader attached thereto;
FIG. 2 is a sectional view showing a sensor;
FIG. 3 is a rear view showing operating means;
FIG. 4 is a rear view in section showing the operating means;
FIG. 5 is a view in section taken along the line X--X in FIG. 4;
FIG. 6 is a view in section taken along the line Y--Y in FIG. 4;
FIG. 7 is a diagram of a hydraulic circuit;
FIG. 8 is an electric circuit diagram of control systems;
FIG. 9 is a diagram showing the waveforms of signals;
FIG. 10 is a diagram illustrating control positions;
FIG. 11 shows postures of a bucket as related to the sensor;
FIG. 12 is a diagram illustrating voltage setting;
FIGS. 13 and 14 are diagrams for illustrating operation;
FIG. 15 is a diagram showing the relation between the posture of the tractor and sensors;
FIGS. 16 to 22 show a second embodiment of the invention;
FIG. 16 is a hydraulic circuit diagram;
FIGS. 17 and 18 are electric circuit diagrams showing control systems;
FIG. 19 is a diagram showing signal waveforms;
FIG. 20 is a side elevation in section showing operating means;
FIG. 21 is a rear view in section showing the operating means;
FIGS. 22 to 24 are electric circuit diagrams showing other embodiments of the invention; and
FIG. 25 is a hydraulic circuit diagram showing another embodiment of the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The present invention will be described below in detail with reference to the illustrated preferred embodiments.
FIGS. 1 to 15 show a front loader embodying the invention and attached to a tractor.
With reference to FIG. 1, indicated at 1 is the tractor body, at 2 front wheels, at 3 rear wheels, at 4 a rear wheel fender, and at 5 a driver's seat. The front loader, which is indicated at 6, comprises a pair of opposite masts 8 removably attached in an upright position to opposite sides of the tractor body 1 by a pair of opposite mount frames 7, a pair of opposite booms 10 liftably mounted by pivots 9 on the upper ends of the masts 8, a pair of opposite boom cylinders 11 for raising or lowering the booms 10, a bucket (working device) 13 rotatably supported by a pivot 12 on the forward end of each boom 10, and a pair of opposite bucket cylinders 14 for pivotally moving (rotating) the bucket 13.
An inclination sensor 15 for detecting the inclination of the tractor body 1 is mounted on the front loader 6, for example, on one of the pair of masts 8. A posture sensor 16 for detecting the posture of the bucket 13 when it is rotated is attached to a bracket 17 on the rear side of the bucket 13. As seen in FIG. 2, these sensors 15, 16 comprise a weight plate 21 and a variable resistor 22 provided respectively in two separated chambers 19 and 20 within a box-shaped case 18. The weight plate 21 is mounted on a rotatable shaft 23 supported by the case 18, while the variable resistor 22 is operatively connected by the shaft 23 to the weight plate 21. Accordingly, a change in the posture of the tractor body 1 or the bucket 13 moves the weight plate 21, causing the resistor 22 to produce a voltage signal in accordance with the posture. A damper oil 23a is contained in the chamber 19.
With reference to FIGS. 3 to 6, operating means 24 comprises a case 25 mounted on the rear-wheel fender 4 at one side of the driver's seat 5, an operating lever 26 movable forward, rearward, leftward, rightward or in any one of different oblique directions and supported by the case 25, first and second variable resistors 27, 28 accommodated in the case 25 and operatively connected to the operating lever 26, etc. More specifically, the operating lever 26 is supported by a transverse rod 30 on a movable frame 29 which is rectangular when seen from above and which is supported by longitudinal rods 31 to the case 25. Accordingly, the operating lever 26 is movable in a desired direction as indicated by arrows in FIG. 6, about the two axes, intersecting each other at right angles, of the transverse rod 30 and the longitudinal rods 31. The lever 26 is resiliently held in a neutral position by unillustrated spring means. The first variable resistor 27 constitutes raising-lowering instruction means for instructing the booms to rise or lower, is operable by the forward or rearward movement of the operating lever 26 through the transverse rod 30 and produces a raising or lowering (up-down) instruction signal of a voltage which varies with the amount of movement or manipulation of the operating lever 26. The second variable resistor 28 constitutes rotation instruction means for instructing the bucket 13 to rotate, and is operable by a left or right movement of the operating lever 26 through the longitudinal rod 31 and the movable frame 29 to produce an instruction signal of a voltage which varies with the amount of manipulation of the lever 26.
The operating lever 26 has a posture holding switch 32 of the push button type at its upper end and a semispherical actuating portion 33 at its lower end. Provided within the case 25 at its bottom are a raising switch 34, lowering switch 35, dumping switch 36 and a scooping switch 37 which are arranged around the actuating portion 33 in front and rear thereof and at left and right sides thereof, respectively. These switches are actuated by the portion 33 when the operating lever 26 is manipulated to the greatest extent. A flexible cover is indicated.
FIG. 7 shows a hydraulic circuit for the lift cylinder 11 and the bucket cylinder 14. A first proportional solenoid valve 39 of the flow proportional type for controlling the lift cylinder 11 has a raising solenoid 40 and a lowering solenoid 41. A second proportional solenoid valve 42 of the flow proportional type for controlling the bucket cylinder 14 has a dumping solenoid 43 and a scooping solenoid 44.
The proportional solenoid valves 39 and 42 are driven under the control of a control circuit shown in FIG. 8. With reference to FIG. 8, first discriminating means 45 for discriminating the direction of upward downward movement comprises two comparators 46, 47, a variable resistor 48 provided therebetween for setting a dead zone ±alpha, etc. When the instruction signal from the first variable resistor 27 is greater than an upper reference value, 1/2V+alpha, the comparator 46 produces an up signal, while if the signal is smaller than a lower reference value, 1/2V-alpha, the comparator 47 produces a down signal. Second discriminating means 49 for discriminating the direction of movement for dumping or scooping comprises two comparators 50, 51, a variable resistor 52, etc. like the first means 45. The comparator 50 produces a dumping signal, or the comparator 51 produces a scooping signal 51, in accordance with the instruction signal from the second variable resistor 28.
A triangular wave oscillation circuit 53, serving as a reference signal generating means, generates a reference signal of predetermined frequency, i.e. a triangular wave signal a as seen in FIG. 9. First comparison means 54 comprises two comparators 55, 56 and compares the instruction signal b from the first variable resistor 27 with the triangular wave signal a from the oscillation circuit 53 to produce a pulse signal c of a width in proportion to the variation of the instruction signal b, i.e. to the amount of manipulation of the operating lever 26, as seen in FIG. 9. The comparators 55 and 56 are in opposite relation to each other with respect to the input of the instruction signal b and the triangular wave signal a. The comparator 55 is on when the instruction signal b is greater than the triangular wave signal a and is off when the signal b is smaller than the signal a, producing the pulse signal c of FIG. 9. The comparator 56 is on when the signal b is smaller than the signal a and is off when the signal b is greater, in reverse relation to the case shown in FIG. 9. Second comparison means 57 comprises two comparators 58, 59 and, like the first comparison means 54, produces a pulse signal of a width in proportion to the instruction signal from the second variable resistor 28, based on the instruction signal and the triangular wave signal from the oscillation circuit 53.
First drive means 60 converts the pulse signal from the first comparison means 54 into an electric current to drive the first proportional solenoid valve 39. The drive means comprises switching elements 61, 62 connected to the solenoids 40, 41 and analog switches 63, 64 for applying the pulse signal from the comparators 55, 56 to the elements 61, 62, respectively. When the signal from the comparators 55, 56 of the first discriminating means 54 is fed to the analog switches 63, 64, the switching elements 61, 62 are turned on and off in synchronism with the pulse signal. Like the first drive means 60, the second drive means 65 for converting the pulse signal from the second comparison means 57 into an electric current to drive the second solenoid valve 42 comprises switching elements 66, 67 and analog switches 68, 69.
Sample holding means 70 is adapted to hold an input signal from the posture sensor 16 for a predetermined period of time when the holding switch 32 on the grip of the operating lever 26 is turned on. Means 71 for setting the desired position of the bucket 13 comprises a posture selection switch 72 for selecting and setting one of a bottom horizontal voltage Vr1 required for making the bottom of the bucket 13 horizontal, an opening horizontal voltage Vr2 required for making the bucket opening horizontal and a voltage supplied from the inclination sensor 15 and indicating the inclination of the tractor body 1. The inclination sensor 15 is used for placing the bottom of the bucket 13 on the ground. A change-over switch 73 is provided for selecting the signal from the sample holding means 70 or the signal from the setting means 71. Inversion means 74 is adapted to invert the signal from the change-over switch 73 with reference to a reference voltage 1/2V at an N terminal. Deviation detection means 75 adds the signal from the inversion means 74 to the signal from the posture sensor 16 to detect the difference therebetween, which is then amplified by an inverter 76. A manual-automatic change switch 77 is closed at a contact 77a for manual control to transmit the instruction signal from the second variable resistor 28, or at a contact 77b for automatic control to transmit the signal from the deviation detection means 76. The signal is fed from the switch 77 to the second discrimating means 49 and to the second comparison means 57. As seen in FIG. 3, the switches 72, 73 and 77 are mounted on the rear side of the case 25 along with a power supply switch 78.
The first variable resistor 27, first discriminating means 45, first comparison means 54, first drive means 60 and first proportional solenoid valve 39 constitute a boom control system. The second variable resistor 28, second discriminating means 49, second comparison means 57, second drive means 65 and second proportional solenoid valve 42 constitute a working device control system. The triangular wave oscillation circuit 53 singly is provided for the two, control systems.
When the inclination sensor 15 is mounted on the mast 8 of the front loader 6 as seen in FIG. 1, this means that the front loader 6 is provided with both the posture sensor 16 and the inclination sensor 15, assuring the advantages that the sensors are adjustable at the factory when the front loader is manufactured and that the loader is easy to attach to or remove from the tractor body 1. However, the inclination sensor 15 may be attached to the tractor body 1.
Further, if the signal from the inclination sensor 15 is shown on a display such as an array of diodes, then the display is usable as an inclination indicator for the tractor. Further if the output of the posture sensor 16 is made visible on a display, then the display serves as a posture indicator for the bucket 13.
Although the change-over switch 73 is provided in addition to the selection switch 72 as seen in FIG. 8, the change-over switch 73 can be dispensed with if the sample holding means 70 is incorporated into the setting means 71.
The working device is not limited to the bucket 13 but may be a fork or some other attachement. In this case, the working devices can be made to be interchangeable as desired by pivoting a mount bracket to the forward ends of the booms and removably attaching the device to the bracket by pins. The posture sensor 16 is then attached to the mount bracket. This assures great convenience, since the need to attach the sensor 16 to the device every time it is replaced is eliminated.
The control apparatus operates as follows for the operation of the front loader 6.
For manual control, the manual-automatic change switch 77 is closed at the contact 77a. Subsequently, the operating lever 26 is manipulated. The operating lever 26 is movable in the directions of the arrows shown in FIG. 6 for the upward and downward movements of the booms 10, dumping and scooping movements of the bucket 13 and combinations of such movements (see FIG. 10). The lever 26 automatically returns to the neutral position in the center when it is released by hand.
Now, when the lever 26 is turned rearward toward "UP", the first variable resistor 27 is operated through the transverse rod 30, giving an altered resistance value in accordance with the amount of manipulation and producing an instruction signal of increased voltage. It is assumed that when the lever 26 is in its neutral position, the resistance value of the resistor 27 is 1/2 of its maximum value and that the voltage then available is 1/2 of the supply voltage V. This will be referred to as a "neutral point." The instruction signal from the first resistor 27 is fed to the comparators 46, 47 of the first discriminating means 45. Since the signal is greater than the neutral point, the comparator 46 interprets this as indicating an upward movement to produce an up signal, which actuates the analog switch 63 of the first drive means 60. The instruction signal from the first resistor 27 is also fed to the comparators 55, 56 of the first comparison means 54. Since the instruction signal is greater than the neutral point, the comparator 55 compares the signal with a triangular wave signal from the oscillation circuit 53, produces a pulse signal which is on when the instruction signal is greater than the triangular wave signal as seen in FIG. 9. As the difference between the two signals becomes greater the pulse width of the pulse signal becomes greater. The switching element 61 is repeatedly turned on and off by the pulse signal through the analog switch 63 of the first drive means 60, and intermittently passes an energizing current of a given value through the up solenoid 40 of the first solenoid valve 39. The valve 39 is opened at the up side to a degree in proportion to the amount of manipulation of the lever 26 by virtue of the dither effect involved, consequently extending the boom cylinder 11 at a predetermined speed and raising the boom 10 about the pivot 9. A variation in the amount of manipulation of the operating lever 26 varies the opening degree of the first solenoid valve 39 to control the flow of pressure oil to be supplied to the boom cylinder 11. As a result, the boom 10 is raised at a speed proportional to the amount of manipulation of the operating lever 26. The speed is controllable from very low to high speeds as desired. The lever 26, when returned to its neutral position, returns the valve 39 to its neutral position to stop the boom 10 at the raised position. When the lever 26 is returned slowly at this time, the boom 10 is brought smoothly and slowly to a stop.
The control apparatus operates similarly when the lever 26 is moved forward to lower the boom 10 or when the lever is moved to the right or left to cause the bucket 13 to perform a scooping or dumping action.
When the lever 26 is moved forward or rearward or sideward through the greatest angle, the actuator 33 closes one of the corresponding switches 34 to 37, operating the valve 39 or 42 by energizing one of the corresponding solenoids 40 to 44. Thus, the valve 39 or 42 is operable without resorting to the operation of the control system. In this case, however, proportional control is not available. This mode of control is therefore effected only in the event of a malfunction.
For automatic control, the manual-automatic change switch 77 is closed at the automatic contact 77b. The automatic control is limited only to the postur control of the bucket 13. The boom 10 is controlled in the same manner as above for upward or downward movement by manipulating the lever 26 foward or rearward.
In this case, the posture sensor 16 for detecting the posture of the bucket 13 is used. FIG. 11, (I) to (IV) shows the relation between the posture sensor 16 and the posture of the bucket in scooping, up-down movement with the opening kept horizontal, with the bottom kept horizontal and dumping. FIG. 12 shows the relation between the voltage and the posture sensor 16 for bottom horizontal up-down movement and opening horizontal up-down movement.
Posture control is effected in the following manner for bottom horizontal posture, opening horizontal posture, posture holding and bottom grounding.
Bottom horizontal posture control is resorted to when the boom 10 is lowered to bring the bottom of the bucket 13 horizontally into contact with the ground. In this case, the change-over switch 73 is closed for the setting means 71, and bottom horizontal voltage Vr1 is selected by the selection switch 72. When the bottom of the bucket 13 is in parallel with the horizontal, the voltage (resistance) of the posture sensor 16 is constant at all times irrespective of the posture of the boom 11 or of that of the tractor body 1. Accordingly, the voltage is set equal to the bottom horizontal voltage Vr1 by the potentiometer within the setting means 71 as shown in FIG. 12.
When the selection switch 72 is closed for bottom horizontal, the voltage Vr1 is inverted by the inversion means 74 to a voltage Vr1' about the 1/2V voltage at the N terminal. The voltage Vr1' is added to the voltage detected by the posture sensor 16, the current posture of the bucket 13 by the deviation detection means 75 to determine the difference between the two voltages is indicated, and the resulting output is inverted and amplified by the inverter 76. FIG. 13, (I) to (III) show these characteristics.
If the voltage from the posture sensor 16 is Vr1, then the difference is zero, indicating that there is no need to correct the posture of the bucket 13. The subsequent portion of the system therefore does not function. When the bucket 13 is in a rotated position off a horizontal plane toward the dumping direction, the posture sensor 16 gives an increased voltage, with the result that the deviation detection means 75 produces a deviation voltage (3) as shown in FIG. 13 (III) that is lower than the neutral point voltage. From this deviation voltage, the second discriminating means 49 detects the need for a correction toward the scooping direction. Further the second comparison means 57 compares the deviation voltage with the triangular signal, and a pulse signal of a width in accordance with the deviation voltage is generated. The signal energizes the scooping solenoid 44 of the second solenoid valve 42 via the analog switch 69 and the switching element 67 of the second drive means 65, whereby the bucket cylinder 14 is contracted to correct the posture of the bucket 13 toward the scooping direction. As the posture of the bucket 13 approaches the bottom horizontal posture, the voltage from the sensor 16 diminishes causing the deviation voltage to diminish and the width of the pulse signal to decrease. The bucket cylinder 14 is slowed down and the correcting action at zero deviation is completed. Thus, the bucket 13 is slowed down as it is brought closer to the bottom horizontal posture and eventually comes smoothly to a halt.
Conversely, if the bucket 13 is inclined toward the scooping direction, then the deviation voltage is in the state (2) shown in FIG. 13 (III), and the bucket 13 is moved toward the dumping direction and corrected to the bottom horizontal posture.
The opening horizontal posture control is effected when the boom 10 is raised while holding the opening of the bucket 13 horizontal after scooping up earth or sand with the bucket. For this mode of control, the opening horizontal posture is selected by the selection switch 72. In this case, the opening horizontal voltage Vr2 is set on the potentiometer of the setting means 71 so that it becomes equal to the voltage from the posture sensor 16 becomes equal to when the opening is brought to the horizontal position as seen in FIG. 12.
The control system operates in the same manner as the bottom horizontal posture control, and the operation characteristics are shown in FIG. 14, (I) to (III).
For posture holding control, the change-over switch 73 is closed for posture holding, and the holding switch 32 is turned on.
When the boom 10 is raised after a compost heap of the like is scooped up with the bucket 13, the bucket 13 must be maintained in the scooping state. Otherwise, the upward movement would cause the heap to spill from the bucket 13 toward the operator. Therefore, in such a case, a need to raise the bucket 13 held in the scooping posture arises.
Thus, the holding switch 32 is turned on, with the change-over switch 73 set to posture holding, whereupon a voltage indicating the current posture of the bucket 13 is fed to the sample holding means 70 and is held for a predetermined period of time. The held voltage is inverted by the inversion means 74, whereupon the difference between the held voltage and the voltage from the posture sensor 16 is determined by the deviation detection means 75, which produces an inverted voltage. The posture of the bucket 13 is controlled by this deviation voltage in the same manner as in the foregoing bottom or opening horizontal posture control. Consequently, the boom 10 is raised while the bucket 13 retained in the original posture.
"Bottom grounding posture" refers to the state in which the bottom of the bucket 13 is on the ground in the same plane as the ground on which the front and rear wheels 2, 3 of the tractor body 1 are placed or on which the bottom is on a plane in parallel with the plane as seen in FIG. 15, (I). Bottom grounding control is resorted to when the bucket 13 is lowered onto the ground or used for scooping along the ground surface. This mode of control is very convenient when the bucket 13 is to be placed on the ground since the bonnet then blocks the sight of the operator in the seat 5.
The bottom grounding control differs greatly from the bottom horizontal control. In that in the latter case, control is effected with reference to the angular deviation of the bucket 13 from the direction of gravity. Whereas, the bottom grounding control involves another factor, i.e. the inclination of the tractor body 1, besides the posture of the bucket 13.
Accordingly, the inclination sensor 15 is used for control. As seen in FIG. 15, (II), the setting is so made that the inclination sensor 15 and the posture sensor 16 deliver the same signal voltage (resistance) when the bottom of the bucket 13 is grounded.
The selection switch 72 and the change-over switch 73 are set to the inclination sensor side for bottom grounding. When the tractor body 1 is inclined, the inclination sensor 15 produces an altered voltage that detects the inclination. If the bucket 13 is on the same ground surface as the tractor body at this time, then the posture sensor 16 delivers the same signal voltage as the inclination sensor 15. However, when the voltage from the posture sensor 16 is different, the bucket cylinder 14 functions through the same operation as in the foregoing bottom horizontal posture control where the bucket is brought to a corrected posture in which the bottom is on the ground.
FIGS. 16 to 22 show a second embodiment of the present invention. A first proportional solenoid valve 39 for the boom control system and a second proportional solenoid valve 42 for the working device control system are connected in series with each other as seen in FIG. 16. When these valves 39, 42 are operated at the same time, a hydraulic pump 78 feeds pressure oil to a boom cylinder 11, and the return oil from the cylinder 11 is fed to a bucket cylinder 14. Incidentally in this case, the boom cylinder 11 and the bucket cylinder 14 are mounted in a reverse direction to the case shown in FIG. 1. While the cylinders 11, 14 are approximately identical in capacity and stroke, they may be different from each other in accordance with the length of the boom 10 or the size of the bucket 13. Further although the proportional solenoid valves 39, 42 are approximately identical in size and configuration, they may also be different from each other depending on the size of the cylinders 11, 14, the boom 10 and the bucket 13. Indicated at 79 is a relief valve, and at 80 a hydraulic unit on the tractor body for lifting a working implement. The proportional solenoid valves 39, 42 are controlled approximately in the same manner, and the boom control system and the working device control system are predominantly in a corresponding relation to each other with respect to the constituent circuits and other components, so that like corresponding parts are designated by like reference numerals, with an adscript "a" attached to the numeral for the boom control system or with an adscript "b" attached for the working device control system.
FIGS. 17 and 18 show a main switch 81, a NOT circuit 82, NAND circuits 83, 84, a prepositioned pulse generating circuit 85, instruction pulse generating circuits 86a, 86b and reference pulse generating circuits 87a, 87b. By the action of a monostable multivibrator, each of these pulse generating circuits 85, 86a, 86b, 87a, 87b deliver a pulse signal from an output terminal Q which rises with the input signal to terminal A and falls with a time constant dependent on a capacitor and resistor of a time-constant circuit. While the NOT circuit 82 is producing a high-voltage output, the prepositioned pulse generating circuit 85 produces a pulse signal E1 of a given frequency from an output terminal Q and a pulse signal E2 from an output terminal Q. As seen in FIG. 19, (I), the pulse signal E1 has a pulse width T1 which is determined by the time constant of capacitor C1 and resistor R2 of the circuit. The signal E2 is the inverse of signal E1 as shown in FIG. 19, (II). The instruction pulse generating circuit 86a (86b), which constitutes instruction means along with a variable resistor 88a (88b), receives at input terminal A the pulse signal E1 from the circuit 85 and delivers a pulse signal F1 from output terminal Q which, as seen in FIG. 19, (III), rises with signal E1 and has a pulse width T2 dependent on the time constant circuit of capacitor C2 and resistor R2 and the variable resistor 88a (88b). The circuit 86a (86b) further delivers from output terminal Q a pulse signal F2, which is the inverse of pulse signal F1, as shown in FIG. 19, (IV). The resistance of the variable resistor 88a (88b) is varied by a slider 89a (89b). The reference pulse generating circuit 87a (87b), which serves as a reference signal generating means, receives the pulse signal E1 from the prepositioned pulse generating circuit 85 at input terminal A from output terminal Q and, delivers from a pulse signal G1 which, as shown in FIG. 11, (V), rises with the pulse signal E1 and has a pluse width T3 determined by the time constant circuit of capacitor C3 and resistor R3. Further, a pulse signal G2 is delivered from an output terminal Q which is obtained by inverting the pulse signal G1 as seen in FIG. 19, (VI).
Comparators 90a, 91a (90b, 91b) constitute discriminating means and compare an instruction signal from the slider 89a (89b) on the variable resistor 88a (88b) with a voltage 1/2VDD. When the slider 88a (88b) is moved toward the direction of arrow d (f) beyond a neutral position n which is the midpoint of the resistor 89a (89b), the comparator 90a (90b) produces a high-voltage output. When the slider is moved toward the direction of arrow e (g) beyond the neutral position, the comparator 91a (91b) produces a high-voltage output.
An exclusive OR circuit 92a (92b, 93a, 93b) serving as comparison means compares the pulse signal from the instruction pulse generating cicuit 86a (86b) with the reference pulse signal from the reference pulse generating circuit 87a (87b).
Indicated at 94a (94b, 95a, 95b) is an AND circuit, and at 96a (96b, 97a, 97b) a field-effect transistor, which is connected in series with the solenoid 40 (43, 41, 44). A comparator 98a (98b, 99a, 99b) is connected between the AND circuit 94a (94b, 95a, 95b) and the gate of the field-effect transistor 96a (96b, 97a, 97b) for intermittently driving the transistor with the pulse signal from the AND circuit. One terminal of the comparator 98a (98b, 99a, 99b) is connected between the field-effect transistor 96a (96b, 97a, 97b) and a resistor 100a (100b, 101a, 101b) that is connected in series with the transistor to receive a voltage signal from this resistor. The comparator detects the variation in the energizing current through the solenoid 40 (43, 41, 44) and controls the current amplification by the field-effect transistor 96a, (96b, 97a, 97b) so as to render the current constant. A circuit 102a (102b, 103a, 103b) for protecting the solenoid 40 (43, 41, 44) comprises a diode, capacitor and resistor.
A pressure siwtch 104 is included in the hydraulic circuit of FIG. 16 at the scooping side of the bucket cylinder 14 and is turned on when the internal pressure of the bucket cylinder 14 exceeds a predetermined level (overload). FIGS. 17 and 18 further show a mode change switch 105, NOT circuits 106, 107, NAND circuits 108 to 116 and an AND circuit 117.
FIGS. 20 and 21 show operating means for the variable resistors 88a and 88b. An operting lever 118 is supported by a spherical bearing member 120 on the top plate of a control box 119. The lever 118 has a grip 121 at its upper end and an actuating plate 122 at its lower end. Variable resistors 123a, 124a of the slider type are provided upright within the control box 119 as opposed to longitudinally. Variable resistors 123b, 124b of the slider type are provided upright within the box 119 as opposed to transversely. The resistors of each pair are arranged symmetrically to the operating lever 118. The resistor 123a (123b, 124a, 124b) has a vertically movable slider 125a (125b, 126a, 126b), which is vertically biased by a coiled spring 127a (127b, 128a, 128b) in pressing contact with the lower side of the actuating plate 122. The resistor 123a (123b, 124a, 124b) has its resistance value varied by the movement of the slider 125a (125b, 126a, 126b) and is connected to lead wires on a circuit base plate 129. The resistors 123a, 124a constitute the variable resistor 88a, and the resistors 123b, 124b constitute the variable resistor 88b.
When the operating lever 118 is in a vertical neutral position N, the sliders 89a, 89b in FIG. 17 are in a neutral position n. When the operating lever 118 is moved in the rear as indicated by an arrow D from this position, the slider 89a moves in the direction of arrow d. The lever, when moved in the direction of arrow E, moves the slider 89a in the direction of arrow e. When the lever 118 is moved to the left as indicated by arrow F, the slider 89b moves in the direction of arrow f. When the lever is moved to the right as indicated by an arrow G, the slider 89b moves in the direction of arrow g. Further if the lever 118 is moved to the left and leftwardly rearward, the sliders 89a, 89b are moved in the directions of arrows d, f, respectively. When the lever 118 is moved to the right and rearward, the sliders are moved in the direction of arrows d, g, respectively. When moved to the left and forward, the lever 118 moves the sliders 89a, 89b in the directions of arrow e, f, while when moved to the right and forward, the lever moves these sliders in the directions of arrows e, g. The mode change switch 105 is provided at the top end of the grip 126 of the operating lever 118. The switch is turned on when it is depressed.
With the present embodiment, the capacitors C1, C2, C3 connected to the pulse generating circuits 85, 86a, 86b, 87a, 87b have identical capacitance, while the resistor R3 is one-half of the resistor R1 in resistance value. The resistance of the resistor R2 and the maximum resistance of the variable resistors 88a, 88b are one-third the resistance of the resistor R1. Accordingly, the pulse width T3 of the pulse signal G1 from the reference pulse generating circuits 87a, 87b is 1/2 of the pulse width T1 of the pulse signal E1 from the prepositioned pulse generating circuit 85. When the sliders 89a, 89b are in the neutral position n, the pulse width T2 of the pulse signal F1 from the instruction pulse generating circuits 86a, 86b is 1/2 of the pulse width T1 of the pulse signal E1. As the sliders 89a, 89b move from the neutral position toward the direction of arrow d or f, the fall of the pulse signal F1 is delayed, and the pulse width T2 is gradually increased. When the sliders 89a, 89b are moved in the direction of arrow e or g, the pulse signal F1 falls earlier, and the pulse width T2 is progressively decreasing.
The operation of the present embodiment will be described with reference to the voltage waveform diagram of FIG. 19. When the main switch 81 is turned on, the NAND circuit 84 applies a high voltage to the prepositioned pulse generating circuit 85, which in turn delivers a pulse signal E1 from the output terminal Q and a pulse signal E2 from the output terminal Q The instruction pulse generating circuits 86a, 86b and the reference pulse generating cicuits 83a, 83b receive the pulse signal E1 from the circuit 85. The instruction pulse generating circuits 86a, 86b deliver a pulse signal F1 from the output terminal Q and a pulse signal F2 from the output terminal Q The reference pulse generating circuits 87a, 87b produce a pulse signal G1 from the output terminal Q and a pulse signal G2 from the output terminal Q.
When the operating lever 118 is in the neutral position N at this time, the sliders 89a, 89b are in the neutral position n. The pulses F1, F2 of the instruction pulse generating circuits 86a, 86b then have the same pulse width as the pulse signals G1, G2 of the reference pulse generating circuits 87a, 87b, with the result that the exclusive OR circuits 92a, 92b, 93a, 93b produce no pulse signal. Further since the sliders 89a, 89b are in the neutral position n, no signal is delivered from the comparators 90a, 90b, 91a, 91b. Consequently, no signal is produced from the AND circuits 94a, 94b, 95a, 95b or from the comparators 96a, 96b, 97a, 97b, and the solenoids 40, 41, 43, 44 remain unenergized.
When the boom 10 is to be lowered by operating the first proportional solenoid valve 39 of the boom control system, the operating lever 118 is moved rearward from the neutral position N. The rearward movement (in the direction of arrow D) of the lever 118 from the neutral position N moves the slider 89a in the direction of arrow d, consequently increasing the pulse width T2 of the pulse signal F1 of the instruction pulse generating circuit 86a in proportion to the amount of movement or manipulation of the operating lever 118. Therefore, the width T2 of the pulse signal F1 becomes larger than the width T3 of the pulse signal G1 of the reference pulse generating circuit 87a, causing the exclusive OR circuit 92a to produce a pulse signal H1 as seen in FIG. 19, (VII). On the other hand, the voltage signal of the slider 89a is lowered when moved in the direction of arrow d, and the comparator 90a produces an up signal of high voltage, which opens the gate of the AND circuit 94a. As a result, the circuit 94 a transmits the pulse signal H1, which is delivered to the field-effect transistor 96a via the comparator 98a. The transistor 96a repeats an on-off action in timed relation with the pulse signal H1. Therefore, an energizing current of a given value intermittently flows through the up solenoid 40. By virtue of the dither effect involved, the first proportion solenoid valve 39 operates with a degree of opening in accordance with the amount of manipulation of the lever 118 to control the flow of oil through the boom cylinder, consequently raising the boom 10 at a speed in proportion to the amount of forward manipulation of the operating lever 118.
When the operating lever 118 is moved forward (toward the direction of arrow E) from the neutral position N, the slider 89a moves in the direction of arrow e. Consequently, the pulse width of the pulse signal F2 of the instruction pulse generating circuit 86a and is increased the exclusive OR circuit 93a produces a pulse signal H2 as seen in FIG. 19, (VIII). Further, the movement of the slider 89a toward the direction of arrow e causes the comparator 91a to produce a signal, which opens the gate of the AND circuit 95a. Consequently, the transistor 97a repeats an on-off action as in the foregoing case, and an energizing current of a given value to flow through the down solenoid 41. By virtue of the dither effect involved, the first proportional solenoid valve 39 effects the flow control in accordance with the amount of rearward movement of the lever 118 to lower the boom 10 at a speed in proportion to the amount of rearward movement of the lever 118.
Next, when the bucket 13 is to be used for scooping by operating the second proportional solenoid valve 42 of the working device control system, the operating lever 118 is moved to the left (in the direction of arrow F) from the neutral position N, whereby the slider 89b is moved in the direction of arrow f. Consequently, in the same manner as already described, the exclusive OR circuit 92b produces a pulse signal H1 as shown in FIG. 19, (VII), and the gate of the AND circuit 94b is opened to pass the pulse signal H1 therethrough. Further if the operating lever 118 is moved to the right (in the direction of arrow G) from the neutral position N, then the slider 89b moves in the direction of arrow g. Consequently the exclusive OR circuit 93b produce a pulse signal H2 as seen in FIG. 19, (VIII) and the gate of the AND circuit 95b, is opened which in turn passes the pulse signal H2 therethrough.
When the mode change switch 105 is off, the NOT circuit 107 applies a low voltage to the NAND circuits 109, 110 and to the NAND circuits 113 and 114 NAND circuit 111 invests the output signal of the AND circuit 94a. The pulse signal H2 of the AND circuit 95a is delivered as inverted by the NAND circuit 110. Further via the NAND circuit 115, the pulse signal H1 from the AND circuit 94b is delivered as it is from the NAND circuit 116.
When the mode change switch 105 is on, the NOT circuit 107 applies a high voltage to the NAND circuits 109, 110, 113 and 114. The NAND circuit 109 delivers an output of low voltage, and the NAND circuit 111 delivers an output of high voltage. Via the NAND circuit 110, the pulse signal H2 from the AND circuit 95a is delivered as it is from the NAND circuit 112. Similarly, via the NAND circuit 114, the pulse signal H1 from the AND circuit 94a is delivered as it is from the NAND circuit 116.
When the pressure switch 104 is off, the NOT circuit delivers an output of low voltage, and the NAND circuit 108 produces an output of high voltage which opens the gate of the AND circuit 117. The pulse signal H2 from the AND circuit 95b is fed out as it is from the AND circuit 117.
When the pressure switch 104 is on, the output of the NOT circuit 106 is of high voltage, so that if the output of the comparator 90a is a high voltage, that is, if the operating lever 118 is turned to a rearward position, then the NAND circuit 108 produces a low voltage and the NAND circuit 111 produces a high voltage. In this case, the output of the comparator 31a is a low voltage, so that the output of the NAND circuit 110 is a high voltage, and the NAND circuit 112 produces a low voltage. On the other hand, if the output of the comparator 90a is low, that is, the lever 118 is in a rearward position, then the pulse signal H2 of the AND circuit 95b is delivered as it is from the AND circuit 117.
Accordingly, when the mode change switch 105 is off, the pulse signal H2 from the AND circuit 94b is produced from the NAND circuit 116, and the pulse signal H2 from the AND circuit 95b is delivered from the NAND circuit 112. Alternatively, if the mode change switch 105 is on, then the pulse signal H1 of the AND circuit 94a is produced from the NAND circuit 116, and the pulse signal H2 of the AND circuit 95a is fed out from the NAND circuit 112. However, when the pressure switch 104 is on by turning the operating lever 118 in a rearward position, the NAND circuit 112 delivers a low voltage irrespective of whether the mode change switch 105 is on or off.
When the operating lever 118 is moved left with the mode change switch 105 in its off state, the pulse signal H1 from the AND circuit 94b is fed to the field-effect transistor 96b via the NAND circuits 115, 116 and the comparator 98b, and the transistor 96b repeats an on-off action in synchronism with the pulse signal H1. Consequently, an energizing current of a given value intermittently flows through the dumping solenoid 43 and, owing to the dither effect involved, the second proportional solenoid valve 42 effects the flow control in accordance with the movement to the left of the operating lever 118. Thereby, the bucket 13 performs a dumping motion at a speed in proportion to the manipulation to the left of the lever 118. Further when the operating lever 118 is moved right, the pulse signal H2 from the AND circuit 95b is fed to the field-effect transistor 97b via the AND circuit 117, NAND circuits 111, 112 and comparator 99b, and the transistor 97b repeat an on-off action which allows an energizing current of a given value to intermittently flow through the scooping solenoid 44. By virtue of the dither effect involved, the second proportional solenoid valve 42 operates for flow control in accordance with the manipulation to the right of the lever 118, and the bucket 13 performs a scooping motion at a speed in proportion to the manipulation to the right of the lever 118. When the operating lever 118 is moved to the right and rear to raise the boom 10 for the scooping motion of the bucket 13, the forward end of the bucket 13 is likely to bite into hard earth or to become engaged by a rock or the like. If the internal pressure of the bucket cylinder 14 exceeds a specified level in such an event, then the pressure switch 104 is turned on, whereupon the NAND circuit 112 produces a low voltage which discontinues the scooping action of the bucket 13, thereafter the rise of the boom 10 is only allowed when the bucket 14 is held at rest. This obviates the damage due to overloading and eliminates the need to discontinue the operation.
On the other hand, when the operating lever 118 is moved to the rear with the mode change switch 105 depressed and held in an on state, the pulse signal H1 from the AND circuit 94a is fed to the field-effect transistor 96b via the NAND circuits 114, 116 and the comparator 98b, and the transistor 96b repeats an on-off action in synchronism with the pulse signal H1. Consequently, the boom 10 rises at a speed in proportion to the amount of manipulation to the rear of the operating lever 118, and at the same time, the bucket 13 performs a dumping motion at a corresponding speed. Thus, the boom 10 rises with the bucket 13 held substantially at a definite angle of inclination with respect to a horizontal plane. Further, if the lever 118 is similarly moved forward, then the pulse signal H2 from the AND circuit 95a is fed to the field-effect transistor 97b by way of the NAND circuits 110, 112 and the comparator 99b, and the transistor 97b repeats an on-off action. As a result, the boom 10 lowers at a speed in proportion to the amount of forward movement of the operating lever 118 and, at the same time, the bucket 13 performs a scooping motion at a corresponding speed. Thus, the boom 10 lowered while the bucket 13 is held at a given angle of inclination with respect to a horizontal plane.
The mode change means comprises the mode change switch 105, and 109 to 112, NAND circuits 113 to 116, etc. The means for discontinuing the scooping motion of the bucket 13 comprises the NOT circuit 106, NAND circuit 108, AND circuit 117, etc.
FIGS. 22 and 23 show other embodiments. FIG. 22 shows Darlington pairs of transistors 130a, 130t, 131a, 131b, 132a, 132b, 133a, 133b which substitute the foregoing switching circuits of field-effect transistors 96a, 96b, 97a, 97b. FIG. 23 shows solenoid protecting circuits 102a, 102b, 103a, 103b where each comprises a Zener diode.
FIG. 24 shows another embodiment which is obtained by omitting the mode change switch 105, NOT circuit 107, NAND circuits 109 to 112 and NAND circuits 113 to 116 from the foregoing embodiment.
The pulse width and the frequency of the pulse signals to be generated by the circuits 85, 86a, 86b, 87a, 87b are adjustable by variably setting the values of the resistors R1, R2,R3, 35a, 35b so as to be most suited to the performance or characteristics of the proportional solenoid valves 39, 42.
Although the operating lever 118 is used as operating means for raising or lowering the boom 1 and for moving the bucket 13 for scooping or dumping, the operating means is not limited to the lever 118 but can be of the dial type. Further separate operating means are usable; one for moving the boom 10 and the other for moving the bucket 13.
FIG. 25 shows another embodiment of hydraulic circuit. Channels 134, 135 for connecting the boom cylinder 11 to the proportional solenoid valve 39 are provided with a floating solenoid valve 136 for bringing the channels 134, 135 into or out of communication with each other. When the valve 136 is energized, the two cylinder chambers of the boom cylinder 11 communciate with each other via the channels 134, 135 to render the boom 10 movable upward or downward in a floating state. | A control apparatus having a boom control system for controlling the movement of a liftable boom supported by a vehicle body and a working device control system for controlling a working device pivoted to the boom. Each of the control system includes a proportional solenoid valve and comprises an instruction circuit for producing an instruction signal in accordance with the amount of manipulation of an operating lever, discriminating circuit for determining the direction of operation of the valve from the instruction signal, a reference signal generator, a comparison circuit for comparing the instruction signal with the reference signal from the generator to obtain a pulse signal of a width in proportion to the amount of manipulation, and drive circuit for converting the pulse signal into a current to drive the valve in the direction determined by the discriminating circuit. The boom, as well as the working device, is movable at a speed corresponding to the amount of manipulation of the operating lever. | 4 |
BACKGROUND OF THE INVENTION
In the field of body exercise and strength training, there is a need to exercise the lower extremities under a resistive load. Various exercises have been devised to strengthen hip and leg muscles of the body through squatting exercises and leg lifting exercises. To increase the exercise level, the person performing the exercise may carry weights on the shoulders while doing squatting exercises. However, squatting exercises place great stress on knee joints, ligaments, and tendons, and can lead to injury if not performed properly and with care. In addition, the use of carried weights to further load the musculature presents the problem of reduced stability with a raised center of gravity which occurs when a barbell is placed on the shoulders.
Some exercise machines nave been devised to facilitate exercise of leg muscles under load. The known devices fail to vary the load between stages in the exercise when the body is weaker such as at the bottom of a squat maneuver. A need exists for an exercise machine which can be safely used to effectively resist the action of the lower extremity muscles and thereby to provide strengthening while providing a load which varies between positions during the exercise.
SUMMARY OF THE INVENTION
The present invention relates to exercise machines and in particular to apparatus to allow an athlete to increase lower body strength. A supporting frame is provided with an inclined foot plate on which the user stands. A vertical arm extends from the frame at a distance from the foot plate. A pivot arm is pivotally mounted at the top of the vertical arm, the pivot arm being pivotable in a vertical direction. An upright mast is pivotably fixed to the frame near the foot plate, and movable in a plane in which the pivot arm moves. The pivot arm is provided with a pivotable head member on its free end, the head member being slidable along the mast and having a locking plug which can be selectively entered into one of a plurality of openings along the mast in order to retain it in a fixed vertical position when the user is becoming stationed on the machine. The head member further is provided with a pair of shoulder rests which extend from the head member and have a space between them such that the rests can touch the shoulders of the user with the user's head placed between the rests. Handholds also depend outwardly and downwardly from the head member to provide grips for the hands of the user in a comfortable, natural position.
The pivot arm is provided with a weight suspending bar which depends from a point along the pivot arm at an angle of approximately 65 degrees. The weight suspending bar has a tranverse weight arm at its free end on which free weights of the common type can be suspended.
The foot plate of the frame is inclined downwardly from the outside of the frame toward the mast pivot so that the user will be prompted to lean forward slightly when using the apparatus.
The locking plug of the head can be disengaged from the mast to allow the head member to be alternately lowered and raised as it slides along the mast. As the user lowers the trunk of his or her body, the force exerted by the weights on the transverse weight arm is increased as the user pushes the head upwardly along the mast. Hence the resistance increases as the natural strength of the user increase as the user returns to a standing position.
An optional toe plate may be stationed over the foot plate near or at the outer edge of the frame. The toe plate is shaped to provide an inclined surface on which the user may place the forward part of his or her feet. The slope of the surface is inclined upward toward the mast. The toe plate allows the user to exercise lower leg and foot muscles by relaxing the heel onto the surface of the toe plate and then positioning the shoulder rests on the user's shoulders and then forcing the head member upward on the mast as the heels are raised from the surface of the toe plate.
It is an object of the invention to provide an exercise apparatus to build leg and hip strength of a user.
It is a further object of the invention to provide a leg strengthening apparatus which causes the user to perform exercises at the minimal risk of injury to the ligaments, tendons and joints in the legs and knees.
It is a further object of the invention to provide exercise apparatus to strengthen hip and leg muscles which distributes the weight to the user's body in a safe and efficient manner.
It is a further object of the invention to provide exercise apparatus which increases the resistive force of the apparatus as the position of the user changes to a stronger position.
It is a further object of the invention to provide an exercise apparatus which is variable in application of force to the user through use of readily available free weights.
It is a further object of the invention to provide an exercise apparatus which may be adjusted for differing sizes and strengths of athlete users.
It is a further object of the invention to provide means for an athlete to perform squatting exercises with weights without losing stability and without the need for a spotter.
These and other objects Of the invention will become apparent from examination of the description and claims which follow.
DESCRIPTION OF THE DRAWING FIGURES
FIG. 1 is a front left perspective of the invention in a locked position with the head and pivot arm midway along the mast.
FIG. 2 is a front elevation of the invention with a user in phantom shown in position to commence use of the invention.
FIG. 3 is a front elevation of the invention in a second position showing a user in phantom in a squat position while using the invention.
FIG. 4 is a partly cut away perspective view of the head member of the pivot arm showing its component parts and their engagement with the mast of the invention.
FIG. 5 is a cross section of the mast and head of the invention taken along line 5--5 of FIG. 3.
DETAILED DESCRIPTION OF THE INVENTION
Referring to the drawings, FIG. 1 illustrates the invention 2 in a front left perspective view. Invention 2 is provided with a base frame 4 from which upwardly extends a support arm 6 which is located at first end 8 of frame 4. Frame 4 supports a foot plate 10 which is located adjacent second end 12 of frame 4. A beam 14 extends from first side 16 to second side 18 of frame 4 and provides a support member for mast 20 which is pivotally mounted to beam 14 of frame 4 at pivot 22. The axis of mast 20 is coplanar with the axis of support arm 6 and mast 20 is movable relative to its pivot 22 in this plane. A brace 24 is conveniently interconnected between beam 14 and support arm 6 for stability of support arm 6.
At upper end 26 of support arm 6 is pivotably mounted a pivot arm 28 which is movable vertically about pivot pin 30 in the plane common to the axes of mast 20 and support arm 6. Depending from pivot arm 28 along its length are weight support arms 32, 33 which are provided with transverse rod 34 at the free end 36 of weight support arm 32, 33. Weight support arms 32, 33 extend downwardly from pivot arm 28 and toward mast 20. In the preferred embodiment, weight support arms 32 and 33 are paired and fixedly mounted to opposing sides of pivot arm 28 such that each is generally coplanar with mast 20. Weight arms 32 and 33 may be substituted by a single arm fixed to pivot arm 28.
The pivot arm 28 is provided with a head member 38 which is pivotably movable upon pivot arm 28 about axle 40 and is fashioned to ride up and down along mast 20.
Shoulder rests 42, 43 depend generally horizontally from head member 38 to overlie foot plate 10 and are spaced apart sufficiently to allow a user to position his or her head between shoulder rests 42 and 43. Shoulder rests 42 and 43 are provided with cushions 44, 45 which are of suitable resilient material, e.g. foam rubber, to reduce abrading which might occur when the user's shoulders are in engagement with shoulder rests 42 and 43. In the preferred embodiment, head member 38 comprises first and second plates 46 and 48 which are spaced apart and parallel and disposed on opposing sides of mast 20. Guide rollers 50 and 52 are mounted in plate 46 to engage mast 20. Similar rollers are mounted to plate 48. A lock 54 is located upon first plate 46.
A transverse bar 56 is mounted to front edges 58 and 60 of plates 46 and 48 respectively to serve as a mounting for shoulder rests 42 and 44. Also depending from bar 56 are hand holds 62 and 64, which extend outward and downward from head member 38 on opposing sides thereof to provide a place for the user to hold the device.
Mast 20 is constructed of a hollow rolled steel bar and has a plurality of vertically spaced openings 66 on first side 68 of mast 20 along the upper end thereof. Openings 66 are provided to interact with lock 54 to selectively retain head member 38 in alternative selected locations along mast 20 when desired. A stop 70 is mounted to the first side 68 of mast 20 to provide a lowermost position for head member 38, thereby providing a safety feature to prevent head member from being slideable along mast 20 below a fixed vertical location.
Foot plate 10 is mounted to frame 4 such that the top surface 72 of foot plate 10 declines from first end 12 of frame 4 to beam 14.
FIG. 1 illustrates the invention 2 with optional toe plate 74 installed. Toe plate 74 is optionally placed to overlie the region of foot plate 10 adjacent first end 12 of frame 4 and provides a top surface 76 which inclines from first end 12 of frame 4 toward mast 20.
It can be seen that the preferred embodiment device provides a device with mast 20 and support arm 6 extending above frame 4 at generally the midline thereof.
Referring now to FIG. 2, a user 100 is shown in phantom in position to use invention 2. User's feet 102 are situated on foot plate 10 of the preferred embodiment device. The optional toe plate 74 has been removed. In a standing position, user 1 00 has released lock 54 which allows head member 38 to follow mast 20 to a point where shoulder rest 42 rests upon the user's shoulder 104. The right hand 106 of user 1 00 is shown grasping hand hold 62. With user 1 00 in a standing position with legs 108 extended, head member 38 is disposed at a first relatively higher position along mast 20. Head member 38 has pivoted about axle 40 and pivot arm 28 has pivoted about pin 30 on upper end 26 of support arm 6 such that shoulder rests 42 and 43 remain generally horizontal and rest on user's shoulder 104. Weight support arm 32 is shown with free weight 110 (shown in phantom) mounted on transverse rod 34. Weight support arm 32 is mounted to pivot arm 28 at an acute angle a which is preferably 65±5 degrees. It can be seen that as pivot arm 28 is rotated about first end 26 of support arm 6 in an upward direction, transverse rod 34 is moved upward and closer to mast 20, thereby increasing the effective moment arm of free weights 110 about pivot pin 30.
FIG. 3 discloses the invention 2 in a second position thereof when user 100 has squatted, thereby bending user's knees 112. As the user 100 squats, shoulder rest 42 follows user's shoulder 104 as it declines and head member 38, having lock 54 released, is permitted to follow mast 20 in a downward path. As head member 38 follows mast 20, mast 20 rotates about pivot 22 toward user 100 and pivot arm 28 is lowered about pivot pin 30. Weight support arm 32 and transverse rod 34 also are lowered and the placement of weight 110 is moved in an arc toward support arm 6 and away from mast 20, thereby reducing the moment of weight 110 about pivot pin 30 and reducing the lifting force needed to be exerted by user 100 on shoulder rest 42. The action of invention 2 can be seen to provide effective, safe resistive force to user 100 with the force declining as the user 100 squats into a relatively weaker position and with the resistive force increasing as the user 100 extends his or her legs 108 into a standing position.
Referring now to FIGS. 4 and 5, the detail of the structure of head member 38 can better be visualized. FIG. 4 provides a partly cut away front left perspective of the head member 38 and mast 20 showing left shoulder rest 43 depending generally horizontally from head member 38. Head member 38 comprises first plate 48 and second plate 46 which are maintained in spaced apart relationship on opposing sides of mast 20 by thrust bearings 80 and 81 which roll along the front and rear of mast 20 as head member 38 traverses mast 20. Guide bearing 50 is mounted within second plate 46 and rolls along first side 68 of mast 20. Lock 54 is mounted within second plate 46.
Referring now to FIG. 5, the head member 38 and mast 20 are shown in section taken along line 5--5 of FIG. 3. First plate 48 of head member 38 has guide bearings 51 and 53 mounted thereto, which roll along the lateral sides of mast 20. Thrust bearings 81 and 83 serve to space first and second plates 48 and 46 and to provide roller bearing upon rear face of mast 20. Lock 54 is shown in an unlocked state in FIG. 3 with plunger 84 thereof displaced from any of openings 66 of mast 20. Lock handle 86 is moved to an unlocked position where plunger 84 is locked in a position displaced from mast 20. When lock handle 86 is moved, spring biasing of plunger 84 causes plunger 84 to be urged toward mast 20 and to locate in an opening 66 as one of openings 66 comes into alignment with plunger 84.
OPERATION OF THE INVENTION
The invention 2 minimizes the risk of injury because of its unique design which causes the loaded weight of the machine to be distributed correctly to the athlete's body. The weight imposed upon the athlete's frame is mechanically proper for safety and muscle growth and the apparatus utilizes the strength promoting effect of free weights and the safety of a machine. The angled foot plate 10 improves hip and low back mechanics while squatting.
The attachment of the load arm 32 and pivot arm 28 to the fixed upright arm 6 allows for variable resistance as the pivot arm 28 moves up and down. Weight plates loaded on the transverse arm 34 move through a downward arc that decreases the resistance to the user while squatting. This decrease in weight at the bottom allows for perfect form and mechanical advantage when the athlete is in his weakest position. As the athlete returns to the standing position, the weight arcs upward and toward the user. This motion increases the weight and corresponds to the increased leverage of the athlete as he straightens up.
The mast 20 stabilizes the head member 28 and provides the locking holes 66 for the lock plunger 84 to engage when the machine is not in use. This allows the machine to be set at any level depending on the users height.
The thrust bearing and guide bearings of the head member 38 allow the user and the weight load to move freely during the up and down movement of the machine. The bearings contact the mast 20 to provide a smooth but tight movement. This structure keeps the plunger 84 aligned with the locking holes 66 in the mast 20. When the lock plunger is engaged in the mast, the head member cannot move. However, by rotating the lock pin the head becomes free to move up or down. To secure the head member 38, the lock handle 86 is rotated back, plunger locates in a mast opening 66, and movement stops. The shoulder thrust pads 42 and 43 rest on the user's shoulders while the user's hands grasp the angled hand grips for balance. The head member transfers the weight load from the transverse arm 34 to the athlete's shoulders and allows for the required movement. The three pivot points allow the weight rack to arc upward and backward or down and forward without binding the main mast.
The mast latching design allows this machine to be used without the help of a spotter. The variable load resistance is provided by the angled weight arm 32 on the pivot arm 28. The angled foot plate 10 and the cushioned shoulder pads 42, 43 enhance good and proper form as do the angled hand grips.
With optional toe plate 74 removed, and selected weight plate 110 placed on transverse arm 34, the user 100 takes position on foot plate 10 and unlocks lock 54 to allow the shoulder rests 42, 43 to rest on the user's shoulders. The lock 54 is reset such that the head member is locked to mast 20 at a fixed height. Once comfortable and ready to begin exercise, the user unlocks lock 54 by rotating lock handle 86 which displaces plunger 84 from the opening 66 of mast 20 in which it was resting. The user may then do squatting exercises by thrusting the pelvis rearward and bending the knees, allowing the head member to roll along mast 20 with the force transferred to the user's shoulders at shoulder rests 42 and 43 declining as user lowers his or her torso into the squat position because the weights 110 swing away from the mast 20 as the head member is lowered.
When the bottom of the exercise is reached, the user may thrust the lower body forward and drive the head member 38 up mast 20 while invention 2 increases the resistance as the user approaches a standing position. By moving the feet closer or farther from mast 20 and the shoulder closer or farther from the head member 38, the user may perform varying exercises.
When the optional toe plate 74 is placed upon the foot plate 10, with the head member 38 locked to the mast 10, the user may position his or her feet upon surface 76 with the heels extending from the lower level of toe plate 74 and unsupported. With the lock 54 disengaged, the user may push the shoulder rest 42, 43 upward by action of the feet and ankles in bringing the heels upward to a level even with the balls of the feet which rest on the surface 76.
Exercise of other body structures may be devised with the apparatus as well. | Exercise apparatus for strengthening the legs and hips of a user. A weight carrying pivot arm rides up and down a pivotable mast when the user squats and rises, causing the resistance of the apparatus to increase as the user approaches a standing position. An optional toe plate may be added to allow exercise of ankle and foot structures. | 0 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to multiplexing type circuits, and more particularly, to such a circuit wherein selected input and output leads thereof can be disconnected.
2. Description of the Prior Art
In a typical prior art multiplexing circuit (FIG. 1 at 10), the circuit 10 can include a plurality of circuit portions 12, 14, 16, each having one or more input leads 18, 20, 22 and one or more output leads 24, 26, 28 connected thereto. The output leads 24, 26, 28 are in turn connected to an overall circuit output lead 30, and control leads 32, 34, 36 are individually connected to respective circuit portions 12, 14, 16 so that the user of the circuit 10 may choose which circuit portion he wishes to have in operation, and then apply input signals thereto and receive output signals therefrom to be applied to the overall output lead 30 of the circuit.
In this manner, the functions of each circuit portion can be applied individually as needed.
Presently, it has been found desirable to initially provide a multiplexing circuit which includes multiple circuit portions only one of which is to be chosen for ongoing future use, while the others may be initially included in but eventually excluded from the overall circuit. In such case, it may be desirable to test each of the circuit portions individually to determine its functionality (by application of high and low signals to appropriate circuit terminals in accordance with an established test program, as is well known), and then to choose the one which most optimally fits the needs of the user.
The multiplexing circuit of the type shown in FIG. 1 lends itself to that testing. However, such a circuit, subsequent to testing, includes the undesired circuit portions as part of the overall circuit, resulting in excessive use of power and a higher degree of loading on the previous and following circuits than is optimum.
SUMMARY OF THE INVENTION
It is accordingly an object of this invention to provide a multiplexing type circuit which allows for testing of individual circuits portions thereof, and subsequent disconnection of these circuit portions which are not desired as part of the overall circuit.
Broadly stated, the invention comprises a circuit having a first and second input leads and an output lead, comprising first circuit means connecting the first input lead of the circuit with the output lead of the circuit, second circuit means connecting the second input lead of the circuit with the output lead of the circuit, and laser programmable means for providing selective disconnection of the first input lead of the circuit from the output lead of the circuit, whereby testing of the first circuit means and second circuit means can be undertaken prior to providing the disconnection.
BRIEF DESCRIPTIONS OF THE DRAWINGS
Other objects of the invention will become apparent from a study of the following specification and drawings, in which:
FIG. 1 shows a typical prior art multiplexing circuit, and FIG. 2 shows the circuit incorporating the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Shown in FIG. 2 is the overall multiplexing circuit 50 which incorporates the present invention. As shown therein, the multiplexing circuit includes circuit portions 52A, 52B, 52C, 52D, each of which includes paired switching transistors 54A, 56A, 54B, 56B, etc. Each circuit portion includes input leads 58A, 60A, etc. which are connected to the respective gates of the transistors 54A, 56A, etc. These input leads 58A, 60A, etc. are connected respectively to overall corresponding input leads 59A, 61A, etc. of the circuit 50. The drains of the transistors 54A, 56A etc. have respective output leads 62A, 64A etc. connected thereto. The output leads 62A, 62B etc. in turn connect to an output lead 66 of the overall circuit 50, while the output leads 64A, 64B etc. connect to an output lead 68 of the overall circuit 50. The output lead 66 connects through a resistor 70 to a voltage supply terminal 72, while the output lead 68 connects through a resistor 74 to the voltage supply terminal 72. The sources of each pair of transistors 54A, 56A, etc. are connected together, and are in turn connected to a respective control line 76A, 76B etc. which connects through a transistor 78A, 78B etc. and resistor 80A, 80B etc. to a ground terminal 82. A voltage supply terminal 84 is connected to the gate of each transistor 78A, 78B etc.
If it is chosen that, for example, the circuit portion 52A be tested, a high voltage signal is applied to the control lines 76B, 76C, 76D through respective diodes 86B, 86C, 86D, each forward biased in the direction from a respective control input line to a respective control line, bringing the sources of the transistors 54B, 56B, 54C, 56C, 54D, 56D high, so that signals applied to those transistors will have no switching effect (the drains of those transistors already being high through being coupled to the voltage supply terminal 72). Thus, with only the control line 76A signal low, full testing of the circuit portion 52A can be undertaken by applying appropriate signals to the input lines 58A, 60A.
If it is then desired that the circuit portion 52B be tested, the signals to control lines 76A, 76C, 76D are taken high, while the signal to control line 52B is held low, and testing of that circuit portion 52B can be undertaken by applying appropriate signals to the gates of transistors 58B, 60B. This testing is undertaken by applying appropriate high and low signals to the gates of the transistors 58B, 60B in accordance with a chosen test program for the particular device involved, as is well known.
The input leads 58A, 60A, 58B, 60B, etc. of each circuit portion include as a part thereof respective disconnectable links in the form of laser programmable fuses 90A, 92A, etc. Likewise, the output leads 62A, 64A, etc. of each circuit portion include as a part thereof respective disconnectable links in the form of laser programmable fuses 94A, 96A, etc. Furthermore, each connection from the reference voltage terminal 84 to the gate of each transistor 78A, 78B, etc. respectively includes a disconnectable link in the form of a laser programmable fuse 98A, 98B, etc.
Once the desired circuit portion is chosen, the other circuit portions can be deleted from the overall circuit 50 by blowing appropriate fuses. In such case, no power is consumed by the deleted circuit portions, and there is no speed penalty suffered by the remaining circuit portion upon such selective disconnection as described above. Blowing of the fuses which are part of the input and output leads reduces loading on the previous and following circuits, while blowing of the fuses connected with all transistors 78A, 78B, etc. avoids use of power as supplied by the voltage terminal 84.
It will readily be seen that each of these circuit portions is testable independently of any of the others, so that power needed to test each such circuit portion can be applied individually thereto. | A multiplexing type circuit includes circuit portions having input and output leads associated therewith, to allow testing of the individual circuit portions, and further includes laser programmable fuses which allow selective disconnection of certain input and output leads as chosen to disconnect circuit portions from the overall circuit as appropriate. | 6 |
BRIEF DESCRIPTION OF THE INVENTION
This invention relates generally to miniature instruments commonly called micromachines. More particularly, this invention relates to a micromachine that operates as a cantilevered ratchet valve.
BACKGROUND OF THE INVENTION
Micromachines (also called micromechanical devices or microelectromechanical devices) are small (micron scale) machines which promise to miniaturize instrumentation in the same way microelectronics have miniaturized electronic circuits. Micromachines include a variety of devices such as motors and gear trains analogous to conventional macroscale machinery. As used herein, the term micromachine or microfabricated refers to any three-dimensional object having one or more sub-millimeter dimensions.
Micromachines have been applied to fluid systems, such as chemical delivery systems. Valves are the most important element in any fluid system because they are the building blocks for almost any kind of fluid control. Valves are essential to direct the flow of fluid and are necessary for most types of pumps. The most common valve in the realm of microfabricated devices is the diaphragm valve. Diaphragm valves come in many forms, but consist primarily of an actuated or energized diaphragm that pushes against an aperture associated with a fluid path. In such a system, the fluid flow is modulated by moving the diaphragm closer to or away from the fluid path aperture. The diaphragm may be actuated by any of a variety of methods including piezoelectric, electrostatic, bimetallic, and phase change.
Although diaphragm valves are not difficult to fabricate as individual devices, they are difficult to fabricate monolithically with other kinds of fluidic components, such as pumps and mixers. Bubble valves solve the problem of system integration. However, bubble valves can only withstand relatively low pressure differentials. Further, bubble valves require a relatively large amount of power, making them unsuitable for many applications.
Another problem with diaphragm valves is that they typically require a continuous input of power to maintain either the open or closed state. Continuous power input to maintain a valve state is a serious liability for low power applications.
In view of the foregoing, it would be highly desirable to develop a new type of microfabricated valve. More particularly, it would be desirable to develop a relatively high pressure valve that consumes a relatively low amount of power. Such a valve should be able to be monolithically fabricated with other fluid components, such as pumps and mixers.
SUMMARY OF THE INVENTION
The apparatus of the invention is a microfabricated valve including a substrate with a fluid path. A main cantilever is positionable in a resting closed state to prevent fluid movement through the fluid path and a resting open state that allows fluid movement through the fluid path. A ratchet cantilever supports the main cantilever in either the resting closed state or the resting open state, such that the main cantilever does not have to be energized to maintain the resting closed state or the resting open state. A valve state transition mechanism selectively energizes the main cantilever or the ratchet cantilever during a valve state transition period to selectively transition between the resting open and closed states.
The method of the invention includes the step of energizing a main cantilever into a deflected state until it engages a ratchet cantilever. The main cantilever is then de-energized such that the ratchet cantilever supports the main cantilever in a locked state. The ratchet cantilever is then energized until it disengages the main cantilever, thereby forcing the main cantilever into a free valve state. The ratchet cantilever is then de-energized when the main cantilever is in the free valve state.
The microfabricated cantilever ratchet valve of the invention consumes little power because it is only energized during valve state transitions. In other words, the device is low powered because it is not energized during open valve states and closed valve states. The valve of the invention withstands relatively high pressures. Further, the valve of the invention can be monolithically fabricated with other fluid components, such as pumps and mixers.
BRIEF DESCRIPTION OF THE DRAWINGS
For a better understanding of the nature and objects of the invention, reference should be made to the following detailed description taken in conjunction with the accompanying drawings, in which:
FIG. 1 is a plan view of a microfabricated cantilever ratchet valve in a closed state.
FIG. 2 is a plan view of a microfabricated cantilever ratchet valve in a transition state.
FIG. 3 is a plan view of a microfabricated cantilever ratchet valve in an open state.
FIG. 4 is a perspective view of a microfabricated cantilever ratchet valve.
FIGS. 5a-5k illustrate the construction of a microfabricated cantilever ratchet valve in accordance with an embodiment of the invention.
FIG. 6 is a plan view of a microfabricated cantilever ratchet valve in accordance with another embodiment of the invention.
FIG. 7 is a plan view of the microfabricated cantilever ratchet valve of FIG. 6 in an open state for a first fluid path.
FIG. 8 is a perspective view of the microfabricated cantilever ratchet valve of FIG. 7.
FIG. 9 is a plan view of the microfabricated cantilever ratchet valve of FIG. 6 in an open state for a second fluid path.
FIG. 10 is a perspective view of the microfabricated cantilever ratchet valve of the invention configured for a normally open state.
FIG. 11 is a perspective view of the microfabricated cantilever ratchet valve of FIG. 10 in a closed state.
Like reference numerals refer to corresponding parts throughout the several views of the drawings.
DETAILED DESCRIPTION OF THE INVENTION
The invention is a micromachined valve for fluidic systems that requires no energy input to remain open or to remain closed. In the preferred embodiment, the cantilevers that form the moving parts of the valve are actuated by differential heating. One side of each cantilever contains a doped polysilicon heating element. Electricity is applied to those heating elements, which creates a thermal gradient across the width of the cantilever. The thermal gradient causes the cantilever to bend due to the different amounts of thermal expansion on one side of the cantilever as compared to the other. Electricity only needs to be applied when changing the state of the valve.
FIG. 1 is a plan view of a microfabricated cantilever ratchet valve 20 in accordance with an embodiment of the invention. The device 20 is preferably fabricated in a silicon substrate 22. As described below, the substrate 22 is processed to create a main cantilever 24 and a ratchet cantilever 26. A valve state transition mechanism is used to move the main cantilever 24 and the ratchet cantilever 26. In one embodiment of the invention, the valve state transition mechanism is implemented with a main cantilever polysilicon heating structure formed in the main cantilever 24, and a ratchet cantilever polysilicon heating structure 30 formed in the ratchet cantilever 26.
The substrate 22 also has an inlet fluid path 32 and an outlet fluid path 34 fabricated into it. In FIG. 1, the main cantilever 24 is blocking the outlet fluid path 34, thus the valve 20 is in a closed state.
FIG. 1 also illustrates a cantilever motion aperture 36 formed in the substrate 22. The aperture 36 allows the cantilevers 24 and 26 to move, as described below.
FIG. 2 illustrates the valve 20 in a transition valve state, moving from a closed state to an open state. The main cantilever polysilicon heating structure 28 is energized when moving from a closed valve state to an open valve state. The energized main cantilever polysilicon heating structure creates a thermal gradient between the bottom side of the main cantilever 24 adjacent to the silicon substrate 22 and the top side of the main cantilever 24 exposed to the cantilever motion aperture 36. This thermal gradient causes the main cantilever 24 to deflect into the cantilever motion aperture 36, as shown with arrow 40. The main cantilever 24 continues to deflect until it engages the ratchet cantilever 26. The main cantilever 24 pushes the ratchet cantilever 26 back, as shown with arrow 42. The main cantilever 24 continues to deflect until its tip passes the tip of the ratchet cantilever 26. This causes the ratchet cantilever 26 to spring back in a direction opposite of the direction shown with arrow 42. The ratchet cantilever 26 is then positioned on the underside of the main cantilever 24, preventing it from covering the outlet fluid path 34. The ratchet cantilever 26 and the main cantilever 24 remain in this position, even after the main cantilever is de-energized. As a result, the valve 20 is in an open state.
FIG. 3 is a plan view of the valve 20 in an open state. In the figure, arrow 44 represents inlet fluid flow, while arrow 46 represents outlet fluid flow.
FIG. 4 is a perspective view of the valve 20 in an open state. The figure dimensionally illustrates the main cantilever 24, the ratchet cantilever 26, the inlet fluid path 32, the outlet fluid path 34, and the cantilever motion aperture 36.
The valve 20 returns to a closed state by energizing the ratchet cantilever polysilicon heating structure 30. This causes the ratchet cantilever 26 to deflect in the direction shown by arrow 42 in FIG. 2 until the ratchet cantilever 26 passes beyond the tip of the main cantilever 24. When this occurs, the main cantilever 24 is no longer supported by the ratchet cantilever 24 and therefore it snaps back to its original position, shown in FIG. 1.
Thus, it can be appreciated that the valve 20 of the invention has a "resting" closed state where energy need not be applied to prevent fluid flow, and a "resting" open state where energy need not be applied to facilitate fluid flow. This allows the valve of the invention to consume relatively little power. Further, the cantilever configuration of the invention can withstand relatively high fluid pressures compared to bubble valves. As will be more fully appreciated after the following discussion, the valve of the invention can be monolithically fabricated with other fluid components, such as pumps and mixers.
Those skilled in the art will appreciate that there are many ways to fabricate the device of the invention. One process flow for the preferred embodiment is shown in FIGS. 5a-5k.
The following processing steps have been used, as described below, to construct a variety of devices, in accordance with the invention. Those skilled in the art will appreciate that a variety of modifications on the specified steps are feasible, yet still within the scope of the invention.
Table I--Preferred Fabrication Steps
A. Standard Clean Wafers
VLSI lab sink
Piranha clean (H 2 SO 4 :H 2 O 2 , 5:1) 10 minutes
Two, one minute rinses in de-ionized (DI) water
Rinse until resistivity of water is >11 MΩ-cm
Spin dry
Piranha clean (H 2 SO 4 :H 2 O 2 , 5:1) 10 minutes
Rinse in DI water for one minute
Dip in 25:1 HF until hydrophobic
Two, one minute rinses in de-ionized (DI) water
Rinse until resistivity of water is >14 MΩ-cm
Spin dry
B. Clean Wafers with Minimal Oxide Strip
VLSI lab sink
Piranha clean (H 2 SO 4 :H 2 O 2 , 5:1) 10 minutes
Rinse in DI water for one minute
Dip in 25:1 HF briefly until native silicon oxide removed
Two, one minute rinses in DI water
Rinse until resistivity of DI water is >14 MΩ-cm
Spin dry
C. Partial Clean Wafers
VLSI lab sink
Piranha clean (H 2 SO 4 :H 2 O 2 , 5:1) 10 minutes
Two, one minute rinses in de-ionized (DI) water
Rinse until resistivity of water is >11 MΩ-cm
Spin dry
D. Deposit Low-Stress Silicon Nitride
Horizontal low pressure chemical vapor deposition reactor
Target thickness as specified
Conditions=835° C., 140 mTorr, 100 sccm DCS, and 25 sccm NH 3
E. Deposit Phosphosilicate Glass(PSG)
Horizontal low pressure chemical vapor deposition reactor
Target thickness as specified
Conditions=450° C., 300 mTorr, 60 sccm SiH 4 , 90 sccm O 2 , and 10.3 sccm PH 3
G. Reflow Phosphosilicate Glass
F. Deposit Low Temperature Oxide (LTO)
Horizontal low pressure chemical vapor deposition reactor
Target thickness as specified
Conditions=450° C., 300 mTorr, 60 sccm SiH 4 , 90 sccm O 2 , and 10.3 sccm PH 3
G. Reflow Phosphosilicate Glass
G. Reflow Phosphosilicate Glass
Horizontal atmospheric pressure reactor
Conditions=1000° C., N 2 , 1 hour
H. Photolithography
1. HMDS prime
2. Photoresist coat
Coat 1 μm of Shipley S3813 (thickness may need to be varied depending on topography and thickness of material to be etched) multi-wavelength positive resist
3. Expose resist
G-Line wafer stepper
Standard exposure time
4. Resist develop
Standard develop using Shipley MF 319
5. Hard bake for 30 minutes
I. Coat Backside with Photoresist
1. HMDS prime
2. Photoresist coat
Coat 1 μm of Shipley S3813 (thickness may need to be varied depending on topography and thickness of material to be etched) multi-wavelength positive resist
3. Resist develop
Standard develop using Shipley MF 319
4. Hard bakefor 30 minutes
J. Oxide Wet Etching
VLSI lab sink
Etch in 5:1 BHF until desired amount of oxide has been removed
Two, one minute rinses in DI water
Rinse until resistivity of water is >11 MΩ-cm
Spin dry
K. Photoresist Strip
Lab sink
PRS-2000, heated to 90° C., 10 minutes
Rinse in three baths of DI water, 2 minutes each
C. Partial, Clean Wafers
L. Silicon Nitride Etch
SF 6 +He plasma etch
Etch until desired amount of nitride has been removed
M. Deposit Undoped Polysilicon
Horizontal low pressure chemical vapor deposition reactor
Target thickness as specified
Conditions=580° C., 300 mTorr, and 100 sccm SiH 4
N. Anisotropic Polysilicon Etch
Chlorine plasma etch
Etch until desired amount of polysilicon has been removed
0. Nitrogen Anneal
Horizontal atmospheric pressure reactor
Conditions=1000° C., N 2 , 1 hour
P. Anisotropic Silicon Wet Etch
Lab sink, heated bath
750 g KOH: 1500 ml H 2 O
Temperature: 80° C.
Q. Oxide Removal Wet Etching
Lab sink
Etch in diluted HF or buffered HF until desired oxide removed
Rinse in deionized water for approximately one hour
R. Deep Trench Etch
Inductively coupled plasma etcher
Advanced silicon etch process
High plasma density low pressure processing system
Fluorine plasma
Etch to desired depth
S. Sacrificial Oxide, PSG and Silicon Nitride Removal
Lab sink
Concentrated HF dip with surfactant if needed, continue until desired sacrificial material has been removed
Rinse for 2 minutes in two tanks of DI water
Rinse for 120 minutes in third tank of DI water
T. Sputter Gold
Low pressure chamber
Gold target
U. Gold Etch
Lab sink
Aqua regent etchant or other commercially available gold etchant
V. Wet Oxidation
Horizontal atmospheric pressure reactor
Conditions=Temperature as specified, water vapor environment
W. Boron Diffusion
Horizontal atmospheric pressure reactor
Solid source boron diffusion
Conditions=Temperature as specified
X. Deposit In Situ Doped Polysilicon
Horizontal low pressure chemical vapor deposition reactor
Target thickness as specified
Conditions=610° C. and 300 mTorr
Y. Etch Back to the Substrate
Chemical mechanical polish machine
Stop on silicon substrate
The device may be fabricated using a Silicon On Insulator (SOI) wafer. As known in the art and as shown in FIG. 5a, an SOI wafer 40 includes an insulator layer 42 sandwiched between a device wafer 44 and a handle wafer 46. The device of the invention has been fabricated with a 525 μm SOI wafer 40. The SOI wafer 40 had a 50 μm device wafer 46 formed of single crystal silicon with an orientation of <100>. A 0.5 μm silicon dioxide layer was used as the insulator 42. The handle wafer 46 was 475 μm thick single crystal silicon with a <100>orientation.
The starting SOI wafer 40 is cleaned (step A). A photolithography operation (step H) is then performed using a first mask to expose what will become the heater areas of the device. The heater areas are then subject to a deep trench etch (step R). The device has been fabricated with trench widths of approximately 3 microns. FIG. 5b is a cross-sectional illustration of a resultant trench 48. FIG. 5b is taken along the line A--A of FIG. 5c, which is a plan view of the SOI wafer 40. FIG. 5c illustrates a trench 48 which will be associated with the main cantilever, and a second trench 50 which will be associated with the ratchet cantilever. The Photoresist is then stripped (step K).
The trenches are then filled with approximately 1.5 microns of doped polysilicon (step X). FIG. 5d illustrates the polysilicon 52. A chemical mechanical polishing back to the silicon substrate is then performed (step Y), resulting in the device shown in FIG. 5e. One micron of undoped polysilicon is then deposited (step M). FIG. 5f shows the undoped polysilicon layer 54. Gold is then sputtered (step T). A photolithography step is then performed (step H), leaving everything but wire trace areas exposed. The gold is then etched (step U). The photoresist is then stripped (step K). FIG. 5g illustrates the resultant gold wire trace 56.
A photolithography operation (step H) is then performed to leave the fluid channel areas exposed. FIG. 5h illustrates the resultant photoresist 58. A deep trench etch down to the oxide layer (step R) is then performed. The resultant device is shown in FIG. 5i. FIG. 5i is a view taken along the line B--B of FIG. 1. Observe then that the area to the right of the main cantilever 24 corresponds to the outlet fluid path 34, while the area to the left of the main cantilever 24 corresponds to the cantilever motion aperture 36.
The sacrificial oxide layer is then etched (step S). The resultant device is shown in FIG. 5j. The cantilevers are now free to move. Care must be taken not to overetch because overetching will cause valve leakage.
A quartz cover wafer is then bonded on top of the silicon device wafer using an epoxy, photoresist or some other bond. The quartz cover 60 is illustrated in FIG. 5k.
Those skilled in the art will appreciate that there are numerous ways to implement the technology of the invention. FIG. 6 illustrates a multiple cantilever embodiment of the invention. In particular, the figure shows two main cantilevers 24A, 24B and two ratchet cantilevers 26A, 26B. Each cantilever of FIG. 6 includes a barb 70 and a cantilever flanged head 72. As shown below, each cantilever of FIG. 6 can operate as both a main cantilever and as a ratchet cantilever. FIG. 6 also illustrates that the multiple cantilever apparatus 20 controls two fluid paths, including inlet fluid paths 32A, 32B and outlet fluid paths 34A, 34B.
In order to route fluid through the first fluid path 32A, 34A, main cantilevers 24A and 24B are actuated in the manner previously described. This causes the cantilever flanged heads 72 of the main cantilevers 24A and 24B to engage the barbs 70 of ratchet cantilevers 26A and 26B, as shown in FIG. 7. This allows fluid to pass through the inlet fluid path 32A to the outlet fluid path 34A. FIG. 8 is a perspective view of the device of FIG. 7.
FIG. 9 illustrates how the same device is used to route fluid through the second fluid path 32B, 34B. Observe that in FIG. 9, the main cantilevers 24A and 24B, were the ratchet cantilevers 26A and 26B of FIG. 8. Thus, it can be appreciated that each cantilever of the embodiments of FIGS. 6-9 can operate as either a main cantilever or as a ratchet cantilever.
FIG. 10 illustrates a microfabricated cantilever ratchet valve 80 in accordance with another embodiment of the invention. The device 80 of FIG. 10 is in a normally open state. That is, the main cantilever 24 normally allows a path between the inlet fluid path 32 and the outlet fluid path 34. When the device 80 is activated, the main cantilever 24 obstructs the path between the inlet fluid path 32 and the outlet fluid path 34, as shown in FIG. 11.
Those skilled in the art will appreciate that there are a number of ways to actuate the cantilevers of the invention. For example, a piezo-electric material, such as PZT or ZnO, deposited on one side of the cantilever could provide the actuation force required. Also, if the spring constant of the cantilvers is reduced they could be actuated by thermal bubble or electrolysis bubble. Other possible actuation methods include magnetic and electrostatic actuation.
Although bulk micromachining of silicon is the preferred method of fabricating devices of the invention, there are other methods available. Injection molding of plastic has been refined to the point that very tiny structures, such as the cantilever ratchet valve, could be injection molded. Also, the cantilever ratchet valve could be fabricated by using new photoresists and UV curable epoxies that can be spun on, or otherwise thinly applied, and then features and components are photolithographically defined in the material. In addition to bulk micromachining in silicon, micromachining of other materials, such as quartz, glass, polysilicon and silicon nitride could be used. In all photolithography steps in the fabrication of the cantilever ratchet valve, alternate methods of lithography could be used, such as X-ray lithography and electron beam lithography.
The foregoing description, for purposes of explanation, used specific nomenclature to provide a thorough understanding of the invention. However, it will be apparent to one skilled in the art that the specific details are not required in order to practice the invention. In other instances, well known circuits and devices are shown in block diagram form in order to avoid unnecessary distraction from the underlying invention. Thus, the foregoing descriptions of specific embodiments of the present invention are presented for purposes of illustration and description. They are not intended to be exhaustive or to limit the invention to the precise forms disclosed, obviously many modifications and variations are possible in view of the above teachings. The embodiments were chosen and described in order to best explain the principles of the invention and its practical applications, to thereby enable others skilled in the art to best utilize the invention and various embodiments with various modifications as are suited to the particular use contemplated. It is intended that the scope of the invention be defined by the following Claims and their equivalents. | A microfabricated valve includes a substrate with a fluid path. A main cantilever is positionable in a resting closed state to prevent fluid movement through the fluid path and a resting open state that allows fluid movement through the fluid path. A ratchet cantilever supports the main cantilever in either the resting closed state or the resting open state, such that the main cantilever does not have to be energized to maintain the resting closed state or the resting open state. A valve state transition mechanism selectively energizes the main cantilever or the ratchet cantilever during a valve state transition period to selectively transition between the resting open and closed states. | 5 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention generally relates to systems and devices which monitor and automatically alter the ambient pressure in an enclosed environment. This invention relates more particularly to enclosed environments in which the ambient air is pressurized. This invention relates most particularly to the pressurized environment of the type found in aircraft.
2. Description of the Prior Art
In the preferred application of pressurized aircraft, the prior art has recognized the need to control cabin pressurization. In particular, the prior art has recognized the need to control the cabin atmosphere in view of sudden depressurizations.
U.S. Pat. No. 4,390,152 sets forth one prior art example of an attempt to control cabin pressure.
U.S. Pat. No. 4,383,666 discloses an attempt to equalize pressure between the upper and lower compartments of an aircraft.
In the broader application, U.S. Pat. No. 2,679,467 discloses a device which is intended to rupture in order to relieve internal pressure within an enclosed environment.
While the prior art has recognized the desirability of controlling the pressure within an enclosed environment, it has not recognized the need to provide an active means for positively responding to the change in pressure over time.
It is an object of the present invention to provide a system which monitors ambient pressure within an enclosed environment and includes a positive means of altering the environment.
SUMMARY OF THE INVENTION
The present invention provides a system for controlling ambient pressure within an enclosed environment. The system is comprised of means for outputting a first signal, generally of a predetermined value. That signal is received in a detecting and comparing means which determines the relative change in the signal over time. Based upon the determination of the signal change, a second signal is generated. The second signal is received by an active device which is capable of altering the ambient pressure within the enclosed environment and responds to the second signal.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an illustrative side view of an aircraft depicting the path of the preferred fiber optic cable around the aircraft.
FIG. 2 is a cross section of an aircraft illustrating one arrangement of the fiber optic cables and the active devices in accordance with the present invention.
FIG. 3 shows one possible arrangement of fiber optic cables, signal sources and detectors.
FIG. 4 shows another possible arrangement of fiber optic cables, signal sources and detectors.
FIG. 5 shows another possible cable arrangement.
FIG. 6 shows an active piercing device in accordance with the present invention.
FIG. 7 shows a detailed view of the construction of the device in FIG. 6.
FIG. 8 illustrates the assembly of a rupture panel and the active device of FIG. 6 in accordance with the present invention.
FIG. 9 is an illustrative view of an aircraft having a plurality of ruptured sections.
FIG. 10 shows an alternative embodiment of the present invention.
FIG. 11 is a schematic representation of a basic system according to the present invention.
FIG. 12 shows the actuator device and the receptive panel of the invention as an assembly.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The preferred embodiment of the invention will be described with reference to the drawing figures and like elements will be identified by the same numeral throughout.
In the present description, the entire aircraft is assumed to be a pressurized containment area for the ease of description. References hereinafter to the enclosed area, cabin area or pressurized containment area will refer to that area of the enclosed environment where it is desirable to detect and respond to sudden pressure changes.
Recent experience indicates that the cabin integrity may be suddenly and catastrophically altered by the loss of a door, a hatch and/or by the loss of the craft's outer skin. Recent experience has also taught us that cabin failures may be precipitated by human error, metal fatigue associated with the repeated cycles of pressurizing and depressurizing the aircraft, design flaws and/or improperly designed maintenance procedures. Since any one or all of these factors is capable of creating a catastrophic loss of cabin pressure, an early warning about the potential for failure or the occurrence of an actual failure in a pressurized containment area is imperative.
Since the system cable is routed by and around the most likely areas for a failure, the system will respond to any loss of integrity in the craft and will provide a warning. If the loss of integrity is not such as to endanger the craft, the system cable provides a means for locating the potential failure area. In the event that an actual failure, such as the loss of a door or the like, takes place, the system will immediately recognize the position of the flaw and will actively respond to control the changes.
With reference to FIGS. 1 and 2, the preferred embodiment will be described. This embodiment utilizes a fiber optic cable which extends throughout the body of the craft. In the preferred embodiment, the fiber optic cable is routed in such a manner as to position the cable proximate to doors, windows, hatches, intake and exhaust ports, emergency ports or ramps and the like.
With reference to FIG. 1, a typical aircraft fuselage 10 is shown with a plurality of windows 12 and two doorways 14. The fiber optic cable is routed along the superstructure of the craft between the outer skin and the interior wall which defines the various compartments. The important element in routing the cable 30 is to locate the cable so as to receive fast, accurate information regarding any failure throughout the craft. Since windows and doors are easily identified potential failures, the cable 30 is routed around them.
With reference to FIG. 2, it can be seen that the fiber optic cable 30 runs through all four quadrants of the tube which defines the fuselage 10. As will be recognized by those skilled in the art, the fuselage 10 is comprised of an outer skin 22 and an interior wall 24 which are secured on a superstructure 26. In addition to the superstructure, 26 the aircraft will have additional structure elements which define ceiling structures 28 and floor structures 20. The tube of the aircraft 10 is effectively divided into a passenger compartment 16 and a cargo or baggage area 18.
In the preferred embodiment, the fiber optic cable 30 is a single continuous cable which has been routed throughout the craft. As will be known to those skilled in the art, all transmission lines, whether they are common copper wire or fiber optics, have a characteristics impedance. In high quality lines, such as fiber optics, that impedance is substantially constant throughout the length of the transmission cable. Since the impedance characteristic is essentially constant, any disturbance in the line will result in a corresponding disturbance in the line impedance at a given point or along a reasonably well defined section. These changes in the characteristic impedance of the transmission line result in an impedance surge having a portion thereof reflected back toward the signal source. The reflected signal arrives at a time delay which is approximately equal to twice the propagation time from the signal source to the point of changed impedance.
In applications, such as telephone transmissions, it has been learned that the change in impedance may be used as a means for verifying the integrity of the transmission line. The transmission line is interrogated by driving a signal of a predetermined value through the cable and observing the reflected impedance. Time-domain reflectometry (TDR) addresses this problem and exploits the fact that transmission line faults invariably cause the signal to be reflected back along the line. As noted previously, the reflected signal will arrive at a time which may be calculated based on the length of the cable and the propagation time from the signal source to the point of changed impedance. Measuring this time delay through TDR can localize the position of the fault. Furthermore, measuring the reflected strength and envelope of the signal can identify the severity of the impedance change and often identify the nature and source of the change.
More recently, the use of optical time-domain reflectometry (OTDR), has resulted in specialized test equipment which will automatically interrogate optical fiber transmission links utilizing this time-domain reflectometry based test. Since the fiber optic cable may be interrogated by OTDR test equipment, the cable may be a continuous cable which extends throughout the aircraft. As will be recognized by those skilled in the art continuous, unspliced fiber lengths of over 5 miles or 11 kilometers are common. The desirability of using an unspliced cable will be explained further hereinafter. Since the fiber optic may be interrogated from a single end and the OTDR equipment will register reflected signals due to changed impedance, there is no necessity for terminating the opposite ends of the cables at the test site. Interrogation of the cable will be described hereinafter with reference to FIG. 11.
As can be appreciated by those skilled in the art, the level of sensitivity in the transmission cable, whether it is of wire or fiber optics, suggests that the present system should be powered by on-board clean lines having specified surge controls. Such clean lines are frequently associated with on-board computers. In the preferred application, the system would be powered by a controlled electrical source, preferably dedicated, and would have a back up system of lithium batteries. One of the primary considerations in selecting fiber optic cable over wire cable is the potential for interference with a wire cable from surges, random charges and natural interference, such as electrical storms and/or lightning strikes.
As noted previously, it is preferred that cable 30 be a continuous length without connectors or splices. This preference is based upon an understanding of the dead zone phenomena which occurs when a fiber optic cable is connected. As a result of the interface at the connection, the OTDR test equipment will receive an overload of reflections from the interface. This overloads the detector for a period of time before it can respond to subsequent reflections which may be produced from the actual cable. Generally, the recovery time translates into a length of interrogated fiber for which the OTDR test equipment is essentially blind. As the number of connectors increase, the potential for additional reflections is increased. The dead zones have been recognized as being particularly troublesome because they have a high probability of shadowing a real fault. Since cables, both wire and fiber optic, are available in lengths which eliminate the need for connectors, it is preferred that connectors be avoided in the cable system.
As will be recognized by those skilled in the art, fiber optic transmission lines are sensitive to even a micro bend. Through the use of OTDR test equipment, it is possible to detect the loss of light through a micro bend in a cable. Such techniques have been recognized in the area of secure transmission lines. As a result of this sensitivity of the cable to even a micro bend, it has been determined that the fiber optic cable 30 may be used as a pressure sensing device to interrogate the structural integrity of the aircraft. Since the cable 30 is originally routed in a set pattern and that pattern can be defined in terms of impedance reflection and light loss, any variation in the environment will create a non-specified deviation in the cable impedance and/or light loss. Stated in another way, a failure in the craft integrity will result in a change in the pressure exerted upon the cable. This change in pressure translates into a change in impedance and/or light loss. That change is detected by the OTDR test equipment.
Since the base line information about the craft is available, it is possible to establish the range of changes which are within the normal compensation or recovery capacity of the aircraft or to calculate and determine that a specific change is within that range associated with the normal operation of the craft. Through the use of computers or other signal processing equipment, the information obtained from interrogating the cable can be quickly compared to base line factors for the aircraft. If the variations are within known and accepted ranges, no responsive action is necessary. In the event that the ranges indicate a catastrophic failure, such as the loss of a cabin door, a loss of a portion of the craft's outer skin or another structural failure which has resulted in sudden depressurization, a signal is output to an active device which will respond to and correct the depressurization problem. As will be recognized by those skilled in the art, a sudden depressurization generally creates a draft within the craft tube that results in personnel and property being drawn to and perhaps through the aperture or rupture in this craft integrity.
In the event that the detected change is not of a catastrophic nature requiring an immediate response, the information may be stored in the record and reviewed by the appropriate ground maintenance crew. For instance, an incipient failure of the skin at a certain altitude may foreshadow a potential failure in that area. Through the use of the present system, it is possible to identify the area which should be inspected by a qualified ground maintenance crew member.
With respect to the preferred use of fiber optics, it will be recognized by those skilled in the art that the interrogation can be made in a very rapid fashion. It will also be recognized that the speed of the light within an optical fiber is influenced by the refractive index of the fiber. Accordingly, the speed within the optic fiber will be reduced from the classical speed of light in a vacuum.
Returning to FIG. 2, a plurality of active rupture devices 50 are shown spaced about the aircraft. The rupture devices 50 will be placed along the length of the aircraft, in places selected according the aircraft design, and about the radius of the aircraft tube. See FIG. 9. In the illustration of FIG. 2, the rupture devices 50 are generally located at 12, 4 and 8 o'clock. Positioned adjacent each of the rupture devices is a rupture panel 70. The rupture devices 50 and the panels 70 will be described in more detail hereinafter. For the present purpose, it has been determined that sufficient rupture devices 50 and rupture panels 70 should be provided so that the total rupture area throughout the craft would equal approximately the maximum cross sectional area of the tube of the aircraft fuselage 10 as it is shown in FIG. 2.
With reference to FIGS. 3, 4 and 5, there are shown alternative arrangements for the detection system of the present invention. It is well recognized in the aviation industry that systems should have redundancy. In the embodiment of FIG. 1, a redundant system would independently duplicate the first system. In the embodiment of FIG. 3, two cables 30 are routed throughout the craft and each cable is connected to a separate signal source 32 which outputs a first signal S1 to interrogate the cable 30. In this embodiment, the interrogation signal, rather than merely being reflected upon itself is received by a detector 34 which performs the base line evaluations previously discussed and will output a responsive signal 32. Since the redundant system may be separately routed, it is possible to create different fiber length configurations and different interrogating systems with the dual sources 32. The output signals S 2 would be the result of a comparison against the base data and would determine whether or not an active response was required.
In the construction of FIG. 4, there is one signal source 32 which outputs the common value signal S 1 , which may be a divided signal or two parallel signals. Once again, the length and characteristics of the cable 30 are known. Accordingly, the information received at the detectors 34 is again compared and the S 2 signal is generated based upon that comparison.
In the embodiment of FIG. 5, the redundant systems are separated and run in opposite directions. Furthermore, the signal sources are positioned on opposite sides of the enclosed environment so that active interrogation by two systems on opposite portions of the cable loop are being conducted simultaneously. Once again, the interrogation data is compared to base data and will generate an output signal S 2 .
In all embodiments, the system will have established base line data and that data is constantly compared to the information developed during the repeated polling or interrogation of the system.
With reference to FIGS. 6 and 7, the active rupture device 50 will be described. Referring first to FIG. 6, the rupture device 50 is generally comprised of a base container 52 which is structurally rigid for securement to the superstructure of the craft, as shown in FIG. 2. The base container 52 is closed by the lid 54. Lid 54 has a center bearing element 56 which surrounds the sleeve 58. Positioned at the free end of sleeve 58 is a rupture element 60. In the preferred embodiment the spear tip or rupture element 60 is comprised of four triangularly shaped blades which generally define a star cutter element.
With reference to FIG. 7, the means for actuating the active rupture device 50 will be described in more detail. Within the base 52, there is a hollow sleeve 62. The hollow sleeve is positioned so as to be on centerline with the interior aperture of the bearing element 56. Positioned within the well of the sleeve 62 is a pyrotechnic device which has a base chamber 64, bellows 66 and the nipple or nose 68. The pyrotechnic device fits snugly within the sleeve 62 and is provided with input leads which extend through a side wall of the sleeve 62 and a side wall of the base 52. The signal S 2 is transmitted over the electrical leads. Pyrotechnic devices of the type described are known to produce linear or non-linear motion based upon the rapid expansion of gas. Once such device is available from ICI Aerospace, P.O. Box 819, Valley Forge, Pa. 19482 as Part No. 1MT170, Bellows Actuator. Variations in the stroke length, force, shape of the bellow nose, firing characteristics and environmental resistance are possible. The use of electrically initiated, single-function actuators suitable for use in the present invention have been known to perform functions such as cutting reefing lines. Two such devices are available from ICI as Product Nos. 1SE166 and 1SE167.
In the present invention, it is preferred that active devices such as the bellows actuator described in FIG. 7 be utilized in the present invention. However, it is recognized that the cutter element 60 may be made subject to a fixed load, such as a compressed spring, retained by a retaining line which would be severed by a cutting element such as the reefing line cutter previously identified.
With reference again to FIG. 7, the sleeve 62 is dimensioned to receive the actuator in a snug fit. The outer sleeve 58 is opened at one end thereof and closed at the free end thereof. The sleeve 58 is dimensioned to fit about the sleeve 62 and to be of such a length that full extension of the actuator will not result in the sleeve 58 being dislocated from the sleeve 62. Through the cooperation of sleeve 68 and sleeve 62, it is possible to retain a fixed rigid centerline. The closed end of sleeve 58 has a recess 59 which receives the nipple or nose 68 of the actuator device. The lower or interior end of the sleeve 58 has an outward flange 57. The flange 57 will not limit the stroke of the sleeve 58 based upon operation of the actuator device, however, it will prevent sleeve 58 from being totally dislocated from the actuator 50 and becoming an independent projectile.
With respect to FIG. 8, there is shown a top plan view of the rupture panel 70 with the rupture device 50 shown in phantom. The rupture panel 70 is preferably of sheet metal of the type normally associated with the skin of the aircraft. The panel is generally rectangular and has a parameter 72 which is mounted on a framing member 74 which extends about the parameter of the panel. The framing member 74 facilitates assembly of the rupture panel member 70 to the aircraft and replacement thereof. Across the surface of the rupture panel 70 in the area enclosed within the frame 74, the rupture panel has preformed shear lines which gene rally define an X pattern 76 across the panel. The shear lines 76 do not extend through the panel and are designed solely for the purpose of controlled rupture. When the actuator device contacts the rupture panel, the cutting element 60 will rupture the panel along the shear lines 76. Due to the combined effect of the rupture device and the outward surge of pressure, the triangular portions 78 of the rupture device will separate from each other and away from the skin of the craft. This will then create an aperture in the skin of the craft having an area substantially equal to that within the parameter frame 74. See FIG. 9 for an illustration of ruptured panels. The shear lines 76 and frame 74 are intended to control the rupture and prevent the loss of sheet material. Alternatively, standard aircraft skin material may be used.
It is anticipated that rupture panels 70 and actuator devices 50 may be designed into new aircraft. However, it is also contemplated that such a device may be advantageously retrofitted to existing aircraft. For ease of assembly and replacement, the frame members 74 is advantageous. However, frame member 74 is also advantageous with respect to the production of a rupture unit which will be described more fully hereinafter with respect to FIG. 12.
With reference to FIG. 10, there is shown an alternative embodiment of the present invention which utilizes pressure sensing devices. In this embodiment, the transmission line 30 is strung throughout the craft as in the previous embodiment. However, detection of pressure variations or changes is made through the use of pressure sensitive devices 100. Such devices are commercially available. Examples are the HEISE® Series 620 pressure transducer and the ASHCROFT® Model K1 Thin Film Pressure Transmitter both available from Dresser Industries of Newtown, Conn. Another example is the line of semiconductors available from Motorola Semiconductor Products Inc. of Phoenix, Ariz. under Model Nos. MPX200 and MPX201. When pressure sensing devices such as device 100 are used, the change in impedance on the transmission line results from a response by the pressure sensor. When localized sensors are used, it is possible to configure the sensor with acceptable variations built in. Accordingly, the sensor will not respond to acceptable variations and will not trigger an active response. In that case where the variation exceeds acceptable tolerance, an action will be called for. Other suitable sensors are available from ICSensors, 1701 McCarthy Blvd., Milpitas, Calif. as Models 80, 81 and 84.
As will be understood by those skilled in the art, present polling techniques permit the testing device to repeatedly poll a position in virtually continuous fashion. This rapid repeated polling will eliminate an unnecessary response due to a defect within the system. In this regard, the redundancy of the system also provides a fail safe check against an accidental positive response.
With reference to FIG. 10, the device 100 may also be used as a signal output to the rupture device 50. Since the cable will continually poll or interrogate the device 100, it can be used to enable the trigger voltage to the pyrotechnic device, see FIG. 7.
With respect to FIG. 11, it schematically represents the interrogation of the fiber optic system. Such an interrogation system could be used with the single continuous length embodiment described in accordance with FIG. 1. In this configuration, a signal source 90, such as a pulsed laser, outputs a signal S 1 . The signal S 1 passes through a directional coupler 92 and into the transmission line 30. As a result of line interrogation by OTDR test equipment, the reflected signal is returned to the directional coupler which recognizes the returned direction element of the signal and outputs those values to the detector/controller 94. The controller 94 will determine differences and compare those differences to the preset fixed values. When controller 94 has identified a non-system variation which requires an active response, a signal S 2 is output to trigger the active response. Trigger actuator 96 may in fact be the active device 50. However, it is preferred that a trigger device be interposed between the controller and the active device 50. The triggering device is primarily intended to avoid the potential for an accidental firing of a pyrotechnic device as a result of a static charge, electrical interference, and/or lightning. Depending on the pyrotechnic device selected, its electrical characteristics and the degree of isolation, the trigger function of element 96 may be eliminated.
With reference to FIG. 12, there is shown an assembly 102 which includes a rupture panel 70 and a rupture mechanism 50. This assembly is particularly intended for retrofit applications where structural members for location of a device may not be readily available. With this in mind, it is anticipated that the parameter frame 74, which secures the rupture panel to the superstructure of the aircraft, will support the rupture device 50. Extending away from the panels 78 and depending from the frame 74 is a rigid frame structure 110 having four depending members which support a center base. Mounted on this center base is the rupture device 50. With this assembly, the attachment of the parameter frame 74, such as by riveting or other methods generally used in aircraft construction, will provide a rigid frame portion which positions the rupture device in the proper predetermined location with reference to the rupture panel 70. This assembly eliminates the possible need to modify the superstructure of the craft in order to install rupture devices and panels in accordance with the present invention.
It will be understood by those skilled in the art that variations in rupture area will be determined by the particular application. In the case of aircraft the rupture panels should be maintained at the minimum size possible so as to avoid structural damage or further damage to structural integrity. Multiple holes will also avoid a reverse rush in the pressurized containment area. Since each single opening will be of a size that is calculated to produce the specified volume of changes and the total openings will be balanced with the size of the containment area, the required balance should be achieved quickly.
In general, it is expected that the total area of the aperture(s) as a result of the response to an event will be large enough to prevent propagation of the rush and/or wave front caused by the failure. Likewise, the location of the aperture(s) will be such as to provide a rapid balancing response.
In the preferred signalling arrangement, a first signal (i.e. 1350 nanometers) is utilized for polling and a second signal (i.e. 1550 nanometers) is utilized for actuating the rupture device. Thus, the separation of the signals is by frequency division. | The present invention provides a system for controlling ambient pressure within an enclosed environment. The system is comprised of means for outputting a first signal, generally of a predetermined value. That signal is received in a detecting and comparing means which determines the relative change in the signal over time. Based upon the determination of the signal change, a second signal is generated. The second signal is received by an active device which is capable of altering the ambient pressure within the enclosed environment and responds to the second signal. | 1 |
BACKGROUND OF THE INVENTION
This application is a continuation-in-part of U.S. Ser. No. 953,819 filed Oct. 23, 1978, now abandoned.
This invention relates to the total synthesis of the antibiotic 6-hydroxymethyl-2-(β-aminoethylthio)-1-carbadethiapen-2-em-3-carboxylic acid (I) and pharmaceutically acceptable salts and esters thereof, which are disclosed and claimed in co-pending, commonly assigned U.S. patent application Ser. No. 933,681 filed Aug. 17, 1978, now abandoned, which application is incorporated herein by reference to the extent that it discloses the utility of I as an antibiotic in animal and human therapy and in inanimate systems. ##STR2##
This invention also relates to certain intermediates which are useful in the synthesis of I.
DETAILED DESCRIPTION OF THE INVENTION
The process of the present invention may conveniently be summarized by the following reaction diagram: ##STR3## In words relative to the above diagram, the glycine ester 2 is prepared by reacting X-substituted acetate 1 with ammonia. Relative to these intermediates species 1 and 2, R 1 is any readily removable carboxyl blocking group such as t-butyl, triphenylmethyl, 2,4-dimethoxybenzyl or the like; and X is a leaving group such as chloro, bromo, iodo, or the like. Typically the reaction 1→2 is conducted by introducing liquid ammonia to 1 in a sealed vessel at a temperature of from -30° C. to 100° C. for from 1 to 24 hours to provide 2. Equivalently, the reaction may be conducted at atmospheric pressure at -33° C. (i.e., refluxing solution of liquid ammonia) for 1-24 hours.
The reaction 2→3 is accomplished by treating 2 with a maleate diester in a solvent such as ethylacetate, aromatic solvents such as toluene, halogenated alkyls such as CH 2 Cl 2 , ether, or the like at a temperature of from 0° C. to 120° C. for from 1/2 to 24 hours. The ester moieties, R 2 , which define the maleate diester may be selected from any convenient carboxyl blocking group such as methyl, ethyl, benzyl, or the like. p The aspartic acid intermediate 3 is N-protected according to the reaction 3→4. R 3 is any convenient N-protecting group such as carbobenzyloxy, carbo-t-butyloxy, carbomethoxy, or the like; and establishment of R 3 is accomplished by reacting the corresponding chloroformate or the like with 3 in an aqueous solvent system at a pH of from 8 to 14 at a temperature of from 0° C. to 100° C. for from 1/2 to 10 hours. Equivalently a nonaqueous system may be used, e.g., CH.sub. 2 Cl 2 , ether, toluene, EtOAc, or the like with, in either class of solvent, from 1 to 10 molar excess of added base (e.g., trialkylamines, NaHCO 3 , Na 2 CO 3 , NaOH, or the like) to trap the HCl generated during the reaction. Suitable reagents for the establishment of R 3 are: benzylchloroformate, methylchloroformate, di-t-butyldicarbonate and the like.
The cyclization of 4 to form pyrrolidinone 5 is accomplished by treating 4 in a solvent such as THF diethyl ether, 1,2-dimethoxyethane, methanol, or the like with a strong base such as sodium methoxide, sodium hydride, or the like at a temperature of from -60° C. to 80° C. for from 1/4 to 10 hours.
Thioketal intermediate species 6 is prepared from 5 by treating 5 with R 2' SH in a solvent such as methylene chloride, toluene, acetic acid, diethylether, EtOAc or the like in the presence of boron trifluoride etherate (BF 3 .OEt 2 ), HBr, trifluoroacetic acid, or the like at a temperature of from 0° C. to 100° C. for from 1/2 to 10 hours. The mercaptan reagent R 2' SH is such that R 2' may be alkyl such as methyl, ethyl, isopropyl, or the like, aralkyl such as benzyl, or aryl such as phenyl.
The reaction 6→7 is accomplished by treating 6 in the presence of a base such as triethylamine, sodium bicarbonate, magnesium oxide, sodium carbonate, NaOH, or the like in a solvent such as CH 2 Cl 2 , toluene, ethylacetate, diethylether, or the like with esterified malonyl halide wherein X is halogen such as chloro and R 4 is any convenient carboxyl blocking group such as ethyl, t-butyl, methyl, isopropyl, benzyl or the like at a temperature of from 0° C. to 100° C. for from 1/2 to 10 hours. Alternatively 6 can be treated with an alkyl hydrogen malonate and a dehydrating agent, such as N,N'-dicyclohexylcarbodiimide.
Cyclization of 7 to yield 8 is accomplished by treating 7 in a solvent such as methanol, t-butanol, diethylether, 1,2-dimethoxyethane, tetrahydrofuran or the like with a strong base such as potassium t-butoxide, sodium methoxide, sodium hydride or the like at a temperature of from 0° C. to 100° C. for from 1 to 48 hours.
The reaction 8→9 is accomplished by heating 8 in an aqueous acid solution (for example 1 to 12 NHCl) at a temperature of from 0° C. to 100° C. for from 1/2 to 24 hours.
The diazotization reaction 9→10 is accomplished by treating 9 in a solvent such as acetonitrile, CH 2 Cl 2 , ether, EtOAc, toluene, dimethylformamide or the like at a temperature of from -50° C. to 60° C. with an azide such as p-toluene sulfonyl azide, p-carboxyphenyl sulfonyl azide or the like followed by the addition of a base such as triethylamine, 1,4-diazabicyclo[2.2.2]octane, pyridine, or the like for from 0.1 to 10 hours.
The carboxyl protecting group R 5 is established by the reaction 10→11. Typically this is accomplished from the acid chloride of 10, which is obtained by treating 10 in a solvent such as methylene chloride or the like, preferably in the presence of a catalytic amount of dimethylformamide, with a chlorinating agent such as oxalyl chloride, thionyl chloride, phosgene or the like for from 1 to 10 hours at a temperature of from 0° C. to 85° C. Reaction of the resulting acid chloride with an alcohol in a solvent such as methylene chloride, ether, ethylacetate, toluene or the like in the presence of a base such as triethylamine, pyridine, N,N-dimethylaniline or the like establishes the desired protecting group R 5 . Suitable alcohols for this esterification include benzyl alcohol, p-nitrobenzyl, or the like. Alternatively, 10 may be converted to a mixed carbonic anhydride, which is then treated as indicated to establish R 5 . Stepwise oxidation of 11 provides 12. Typically the thioketal 11 in a solvent such as methylene chloride, toluene, ethylacetate or the like is treated with a stoichiometric amount of an oxidizing agent such as m-chloroperbenzoic acid peracetic acid, sodium periodate or the like at a temperature of from -50° C. to 80° C. for from 1 to 24 hours. The resulting sulfoxide intermediate in a solvent such as acetonitrile CH 2 Cl 2 , Et 2 O, EtOAc, toluene or the like is treated with a 0.2 to 20 fold excess of a strong aqueous acid such as perchloric, sulfuric, hydrochloric or the like at a temperature of from -10° C. to 80° C. for from 0.1 to 5 hours.
The reaction 12→13 is accomplished by treating ketone 12 in an excess of N-protected aminoethanethiol in the presence of boron trifluoride etherate at a temperature of from 0° C. to 100° C. for from 1 to 120 hours. Suitable β-aminoethanethiol reagents include: ##STR4## wherein R 5 is as defined above and is preferably selected from p-nitrobenzyl, benzyl, 2,4-dimethoxybenzyl and the like.
The ring contraction (13→14) is accomplished by treating 13 in the presence of an equivalent amount of a base such as imidazole, pyridine, triethylamine or the like in a solvent such as methylene chloride, ether, toluene, tetrahydrofuran, ethyl acetate or the like at a temperature of from -100° C. to 60° C. under ultraviolet radiation (250 to 400 nm).
The reaction 14→15 is accomplished by treating 14 in the presence of a reducing agent such as diborane, borane-methylsulfide complex or the like in a solvent such as tetrahydrofuran, 1,2-dimethoxyethane, diethyl ether or the like for from 1/2 to 10 hours at a temperature of from -50° C. to 85° C.
The reaction 15→16 is accomplished by treating the thioketal 15 in a solvent such as methylene chloride, toluene, ethylacetate or the like in the presence of 1 to 100 mole % water absorbed on the surface of silica gel or alumina (relative to 15) with sulfuryl chloride or the like.
Double bond isomerization 16→17 is accomplished by treating 16 in a solvent such as dimethylsulfoxide, dimethyl formamide, tetrahydrofuran, toluene or the like in the presence of a base such as 1,5-diazabicyclo[5.4.0]undec-5-ene, diisopropylamine or the like at a temperature of from -20° C. to 70° C. for from 1/4 to 24 hours.
Final deblocking 17→1 is accomplished by hydrogenolysis in a solvent such as dioxane, ethanol, tetrahydrofuran, or the like or an aqueous mixture thereof in the presence of a platinum metal catalyst such as palladium on charcoal, platinum oxide, or the like under an atmosphere of from 1 to 500 psi hydrogen for from 10 to 300 minutes at 0°-25° C.
Referring again to the reaction diagram, intermediate 5 may be accomplished in a single step according to the following reaction scheme: ##STR5## wherein all symbolism has been previously explained.
According to this scheme, the above-defined maleate diester is reacted with a suitably N-protected glycinate ester in the presence of a strong base such as potassium t-butoxide in a solvent such as toluene, diethyl ether, tetrahydrofuran, 1,2-dimethoxyethane or the like at a temperature of from -30° C. to 80° C. for from 1/4 to 6 hours; preferably in the presence of excess t-butylacetate. Another variation in the above scheme of total synthesis may be demonstrated at the level of intermediate 13: ##STR6## wherein all symbolism has been previously explained; intermediate 16 ties in with the above-detailed scheme of synthesis. In words relative to the above variation, species 13 is converted to 13a on treatment with sulfuryl chloride and wet silica gel in a solvent such as CH 2 Cl 2 , toluene, ethylacetate or the like at a temperature of from -100° C. to 40° C. for from 1 to 60 minutes. Ring contraction according to the above-described procedure for the transformation 13→14 accomplishes the transformation 13a→13b. The transformation 13b→16 is accomplished in a procedure exactly analogous to the above described transformation 15→16.
Another variation in the above described scheme of total synthesis may be explained by the following reaction diagram: ##STR7## wherein all symbolism has been previously explained. According to this scheme, intermediate 12 (as defined above) is ring contracted by irradiation according to the procedure detailed for the transformation 13→14 above. The resulting species 12a is converted to 12b according to a procedure exactly analoguous to that described for the transformation 14→15, above. The reaction 12b→12c is accomplished by treating 12b in a solvent such as methylene chloride, diethyl ether, toluene, dimethyl formamide or the like with p-toluenesulfonic anhydride, methanesulfonic anhydride, p-toluenesulfonyl chloride, methanesulfonyl chloride and a base such as triethylamine, pyridine or the like at -10° C. to 60° C. for 1/2 to 5 hours; wherein X is mesyl or tosyl or the like. Establishment of the aminoethylthio side chain is accomplished by treating 12c with N-(carbo-p-nitrobenzyloxy)-2-aminoethanethiol or the like in a solvent such as dimethylformamide, dimethylsulfoxide, hexamethylphosphoramide in the presence of 1 to 2 mole equivalents of a base such as triethylamine, pyridine, or the like, at a temperature of from -10° C. to 50° C. for from 1/2 to 10 hours. The resulting product 16 is treated as described above in the total synthesis.
The compounds of the present invention (I) are valuable antibiotics active against various gram-positive and gram-negative bacteria and accordingly find utility in human and veterinary medicine. Representative pathogens which are sensitive to antibiotics I include: Staphyloccus aureus, Escherichia coli, Klebsiella pneumoniae, Bacillus subtilis, Salmonella typhosa, Pseudomonas and Bacterium proteus. The antibacterials of the invention are not limited to utility as medicaments; they may be used in all manner of industry, for example: additives to animal feed, preservation of food, disinfectants, and in other industrial systems where control of bacterial growth is desired. For example, they may be employed in aqueous compositions in concentrations ranging from 0.1 to 100 parts of antibiotic per million parts of solution in order to destroy and inhibit the growth of harmful bacteria on medical and dental equipment and as bactericides in industrial applications, for example in waterbased paints and in the white water of paper mills to inhibit the growth of harmful bacteria.
The products of this invention may be used in any of a variety of pharmaceutical preparations. They may be employed in capsule, powder form, in liquid solution, or in suspension. They may be administered by a variety of means; those of principal interest include: orally, topically or parenterally by injection (intravenously or intramuscularly).
Such tablets and capsules, designed for oral administration, may be in unit dosage form, and may contain conventional excipients, such as binding agents, for example, syrup, acacia, gelatin, sorbitol, tragacanth, or polyvinylpyrrolidone; fillers, for example, lactose, sugar, cornstarch, calcium phosphate, sorbitol, or glycine; lubricants, for example, magnesium stearate, talc, polyethylene glycol, silica; disintegrants, for example, potato starch; or acceptable wetting agents such as sodium lauryl sulphate. The tablets may be coated according to methods well known in the art. Oral liquid preparations may be in the form of aqueous or oily suspensions, or solutions, or they may be presented as a dry product for reconstitution with water or other suitable vehicle before use. Such liquid preparations may contain conventional additives such as suspending agents, for example, sorbitol, methyl cellulose, glucose/sugar syrup, gelatin, hydroxyethylcellulose, or carboxymethyl cellulose. Suppositories will contain conventional suppository bases, such as cocoa butter or other glycerides.
Compositions for injection, the preferred route of delivery, may be prepared in unit dosage form in ampules, or in multidose containers. The compositions may take such forms as suspensions, solutions, or emulsions in oily or aqueous vehicles, and may contain formulatory agents such as suspending, stabilizing and/or dispersing agents. Alternatively, the active ingredient may be in powder form for reconstitution, at the time of delivery, with a suitable vehicle, such as sterile water.
The compositions may also be prepared in suitable forms for absorption through the mucous membranes of the nose and throat or bronchial tissues and may conveniently take the form of liquid sprays or inhalants, lozenges, or throat paints. For medication of the eyes or ears, the preparation may be presented in liquid or semi-solid form. Topical applications may be formulated in hydro-phobic or hydrophilic bases as ointments, creams, lotions, paints, or powders.
The dosage to be administered depends to a large extent upon the condition and size of the subject being treated as well as the route and frequency of administration--the parenteral route by injection being preferred for generalized infections. Such matters, however, are left to the routine discretion of the therapist according to the principles of treatment well known in the antibiotic art. In general, a daily dosage consists of from about 5 to about 600 mg of active ingredient per kg. of body weight of the subject in one or more treatments per day. A preferred daily dosage for adult humans lies in the range of from about 10 to 240 mg. of active ingredient per kg. of body weight.
The compositions for human delivery per unit dosage, whether liquid or solid, may contain from 0.1% to 99% of active material, the preferred range being from about 10-60%. The composition will generally contain from about 15 mg. to about 1500 mg. of the active ingredient; however, in general, it is preferable to employ a dosage amount in the range of from about 250 mg. to 1000 mg. In parenteral administration, the unit dosage is usually the pure zwitterionic compound in sterile water solution or in the form of a soluble powder intended for solution.
In the foregoing word description of the above schematic reaction diagram for the total synthesis of thienamycin, it is to be understood that there is considerable latitude in selection of precise reaction parameters. Suggestion of this latitude and its breadth is generally indicated by the enumeration of equivalent solvent systems, temperature ranges, protecting groups, and range of identities of involved reagents. Further, it is to be understood that the presentation of the synthetic scheme as comprising distinct steps in a given sequence is more in the nature of a descriptive convenience than as a necessary requirement; for one will recognize that the mechanically dissected scheme represents a unified scheme of synthesis and that certain steps, in actual practice, are capable of being merged, conducted simultaneously, or effected in a reverse sequence without materially altering the progress of synthesis.
The following examples recite a precise scheme of total synthesis. It is to be understood that the purpose of this recitation is to further illustrate the total synthesis and not to impose any limitation. All temperatures are in °C.
EXAMPLE 1
Step A
Preparation of Glycine t-butyl ester ##STR8## A solution of 150.6 g (1.0 mole) of t-butyl chloroacetate and 300 ml of liquid ammonia is stirred in an autoclave at room temperature (25° C.) for 3 hours. The solution is vented and concentrated. Ethyl ether (300 ml) is added to the residue and filtered. The filtrate is concentrated to give 129.1 g of product as a colorless liquid.
Step B
Preparation of N-(t-butylacetate)aspartic acid dimethyl ester ##STR9## Dimethyl maleate (518 g, 3.92 mole) is added to a solution of 129.1 g (0.98 moles) of glycine t-butyl ester in 1.0 liter chloroform at room temperature. The mixture is stirred at room temperature for 3 hours and then extracted with two 300 ml portions of 2 M aqueous hydrochloric acid. The combined aqueous extracts are basified with sodium hydroxide and the product is extracted with ethyl acetate (600 ml). The organic solution is dried (MgSO 4 ) and concentrated in vacuo to give 256 g of the product as a colorless oil.
Step C
Preparation of N-(t-butylacetate)-N-(carbobenzyloxy)aspartic acid dimethyl ester ##STR10## Benzyl chloroformate (165.5 g., 0.97 moles) is added to a mixture of 256 g (0.93 moles) of N-(t-butylacetate)aspartic acid dimethyl ester and 84 g (1 mole) of sodium bicarbonate in 500 ml water. The two-phase solution is stirred at room temperature for 3 hours and then 600 ml EtOAc is added. The organic layer is separated, dried with MgSO 4 , and concentrated to an oil. The oil is treated with 1 liter hexane, cooled to 0°, and filtered to give the pure product (365 g) as colorless prisms, m.p. 69°-72°.
Step D
1-Carbobenzyloxy-2-carbo-t-butoxy-5-carbomethoxy-3-pyrrolidinone ##STR11## To a cold (0°-5°) suspension of 49.7 g (0.92 moles) of sodium methoxide in 300 ml of tetrahydrofuran (THF) is added a solution of 365 g (0.89 moles) of the aspartate derivative in 500 ml of THF over a period of 15 minutes. After aging at 0°-5° for 15 minutes the reaction mixture is quenched by addition of 70 g of acetic acid. After removing most of the solvent in vacuo, the residue is partitioned between EtOAc and two portions of aqueous sodium carbonate solution. The organic layer is dried over MgSO 4 and concentrated to give 225.0 g of crude pyrrolidinone.
Step E
Preparation of 2-Carboxy-3,3-dithiobenzyl-5-carbomethoxy-pyrrolidine ##STR12## To an ice-cooled solution of 2.0 g. (5.3 mmole) of pyrrolidinone and 2 ml. of benzyl mercaptan in 3 ml. of methylene chloride is added 1.5 ml. of boron trifluoride etherate. The resulting suspension is stirred for 2 hours and then 2.0 ml. of trifluoroacetic acid is added and the suspension warmed to 45° for 3 hours. The yellow solution is cooled to room temperature and excess saturated aqueous sodium bicarbonate is cautiously added. The white solid is collected by filtration, washed with several portions of ethyl acetate, and then partitioned between 2 N aqueous hydrochloric acid and ethyl acetate. The organic phase is washed with water, dried over sodium sulfate and evaporated in vacuo to give 0.84 g of a white foamy solid.
Step F
2-Carboxy-3,3-dithiobenzyl-5-carbomethoxy-1-(ethoxycarbonylacetyl)pyrrolidine ##STR13## To a solution of the amino acid (140.2 g, 0.336 moles) and 70.7 g (0.70 moles) of triethylamine in 900 ml CH 2 Cl 2 is added a solution of 54.2 g (0.36 moles) of ethylmalonyl chloride in 100 ml CH 2 Cl 2 over a period of 20 min. at room temperature. The resulting mixture is aged at room temperature for 30 min, then washed with two portions of water, dried (MgSO 4 ), and concentrated in vacuo. The oil is dissolved in 800 ml of toluene, cooled to 0° for 3 hrs, and filtered to give 132.5 g of the product as colorless needles.
Step G
2-Carboxy-3,3-dithiobenzyl6,8-dioxo-1-azabicyclo[3.3.0]octane ##STR14## To a solution of the pyrrolidine (151.6 g, 0.29 moles) in 900 ml CH 3 OH at room temperature is added 67.3 g (0.60 moles) of potassium-t-butyl alcoholate as a solid over 5 minutes. After aging for 24 hrs, the reaction is quenched by adding 42.1 g (0.70 moles) of acetic acid and then concentrated in vacuo. To the residue is added 200 ml of 1 M aq. HCl and 100 ml CH 2 Cl 2 and the resulting solid is collected by filtration to give 144.5 g of the enol ester. The ester is dissolved in 1200 ml acetic acid and 600 ml of 2 N aq. HCl and heated to 75°-80° for 1 hr. The solution is cooled, diluted with H 2 O, and extracted with two portions (400 ml each) of ethyl acetate. The combined organic layers are dried (MgSO 4 ) and concentrated in vacuo to give 105.3 g of the product as a foamy solid. This material is pure enough to use in Step G.
Step H
2-Carboxy-3,3-dithiobenzyle-7-diazo-6,8-dioxo-1-azabicyclo[3.3.0] octane ##STR15##
The bicyclic acid (2.96 g, 6.9 mmole) is dissolved in 50 ml of acetonitrile, cooled in an ice-bath, and treated first with a solution of 2.72 g (13.8 mmole) of p-toluenesulfonyl azide in 7 ml acetonitrile and then with a solution of 1.39 g (13.8 mmole) of triethylamine in 7 ml acetonitrile. The resulting brown solution is warmed to room temperature and aged for 40 minutes, then concentrated in vacuo. The residue is dissolved in ethylacetate and washed successively with 2 N-hydrochloric acid, water, and saturated sodium chloride solution. The organic phase is concentrated in vacuo to give 6.8 g of a red liquid which is chromatographed on 140 g of silica gel. After a forerun of 1% acetic acid in methylene chloride is taken, the product is eluted with 1% acetic acid in ethyl acetate. Concentration gives 2.94 g of the product as a yellow-brown solid.
Step I ##STR16##
2-Carbo-p-nitrobenzyloxy-3,3-dithiobenzyl-7-diazo-6,8-dioxo-1-azabicyclo[3.3.0]octane
To a solution of the acid (2.84 g, 6.27 mmmole) in 20 ml methylene chloride is added 2.10 ml of oxalyl chloride followed by 0.10 ml of N,N-dimethylformamide. The brown solution is aged for 4 hours and then concentrated in vacuo to a brown, oily solid. To an ice-cooled solution of the acid chloride in 16 ml methylene chloride is added a solution of 1.06 g (6.9 mmole) of p-nitrobenzyl alcohol in 3 ml methylene chloride followed by a solution of 0.76 g (6.27 mmole) of N,N-dimethylaniline in 3 ml methylene chloride. The resulting solution is stirred at room temperature for 7 hours and then concentrated. The residue is dissolved in ethylacetate and washed successively with 2 portions of saturated sodium bicarbonate, H 2 O, 2 portions of 2 N hydrochloride acid and water. The organic phase is dried over MgSO 4 and concentrated in vacuo to give 3.1 g of crude ester. Purification is effected by chromatography on 75 g of silica gel. The fractions eluted with 4% ethylacetate in benzene are concentrated to give 2.45 g of ester as a yellow solid. The product can be further purified by recrystallization from 20 ml of diethyl ether to give 2.09 g of yellow prisms, mp=130°-2°.
Step J ##STR17##
2-Carbo-p-nitrobenzyloxy-7-diazo-3,6,8-trioxoazabicyclo[3.3.0]octane
To an ice-cooled solution of the thioketal (1.62, 2.76 mmole) in 20 ml of methylene chloride is added dropwise a solution of 0.48 g (2.76 mmole) of m-chloroperbenzoic acid in 10 ml of methylene chloride. The resulting solution is aged for 15 minutes and then washed with two portions of saturated sodium bicarbonate and then water. The organic phase is dried of MgSO 4 , filtered, and concentrated in vacuo to give the crude sulfoxide (mixture of isomers) as a yellow solid. To a solution of the crude sulfoxide in 2.5 ml of acetonitrile is added 0.53 g of a 72% aqueous solution of perchloric acid diluted with 2 ml of acetonitrile. After stirring for 3 minutes the solution is concentrated in vacuo to a yellow oil. The oil is dissolved in ethylacetate and washed with water and then two portions of saturated sodium chloride solution. The organic phase is dried over MgSO 4 and concentrated in vacuo to give 1.78 g of a yellow gum. The pure ketone is obtained by crystallization from 50 ml of ethylacetate. The pure product amounts to 0.80 g of yellow prisms m.p.=185 (dec).
Step K ##STR18##
2-Carbo-p-nitrobenzyloxy-3,3-bis(N-carbo-p-nitrobenzyloxy-β-aminoethylthio)-7-diazo-6,8-dioxo-1-azabicyclo[3.3.0]octane
A mixture of the ketone (0.23 g, 0.64 mmole) and N-(carbo-p-nitrobenzyloxy)-β-aminoethanethiol (1.82 g, 7.11 mmole) is dissolved in 0.51 ml of boron trifluoride etherate and 10 ml methylene chloride and aged at room temperature for 3 days. The reaction mixture is diluted with ethylacetate and washed successively with water, two portions of 10% lead acetate and solution and water. The organic layer is dried and concentrated in vacuo to give 1.00 g of orange gum. Purification is effected by chromatography on 30 g of silica gel. The fractions eluted with 40% of ethylacetate in toluene are concentrated to give the pure product as a colorless gum (0.38 g).
Step L ##STR19##
2,2-bis(N-carbo-p-nitrobenzyloxy-β-aminoethylthio)-3-carbo-p-nitrobenzyloxy-1-carbadethiapenam-6-carboxylic acid
A solution of the diazo compound (1.65 g, 1.93 mmole) and imidazole (0.13 g, 1.93 mmole) in 35 ml methylene chloride containing 41 mg (2.30 mmole) water is placed in a pyrex vessel fitted with a magnetic stirring bar and a nitrogen inlet tube. The vessel is partially immersed in a dry-ice methanol bath and the solution is thoroughly flushed with nitrogen. The solution is then irradiated for 120 minutes from a distance of 11-15 cm with a 450 watt Hanovia high-pressure mercury vapor lamp fitted with a reflector. The solution is warmed to about 0° and charged on a column of 35 g of silica gel packed in methylene chloride. After a forerun of 25% ethylacetate in benzene, the product is eluted with a mixture of 1% acetic acid and 30% ethyl acetate in methylene chloride. Concentration in vacuo gives the acid (0.68 g) as a pale-yellow gum.
Step M ##STR20##
6-hydroxymethyl-2,2-bis(n-carbo-p-nitrobenzyloxy-β-aminoethylthio)-3-carbo-p-nitrobenzyloxy-1-carbadethiapenam
A 1 M solution (2.69 ml, 2.69 mmole) of borane in tetrahydrofuran is added dropwise to a solution of the β-lactam acid (1.53 g, 1.81 mmole) in 15 ml of anhydrous 1,2-dimethoxyethane at 0° C. The solution is aged at 0° for 50 minutes and then quenched by addition of 1.5 ml of acetic acid. The solution is diluted with ethylacetate and washed with three portions of water, dried, and concentrated in vacuo to give the crude alcohol as a nearly colorless gum (1.49 g). Chromatography on 30 g of silica gel and concentration of the fractions eluted with 50% ethylacetate in benzene gives the pure alcohol (0.69 g) as a colorless gum.
Step N ##STR21##
6-hydroxymethyl-2-(N-carbo-p-nitrobenzyloxy-β-aminoethylthio)-3-carbo-p-nitrobenzyloxy-1-carbadethiapen-1-em
To a cold (-60°) suspension of the thioketal (0.58 g, 0.70 mmole) and wet silica gel (0.11 g of silica and 0.11 g of water) in 15 ml of methylene chloride is added a solution of sulfuryl chloride (0.11 g, 0.84 mmole) in 1 ml of methylene chloride. The suspension is stirred at -60° for 15 minutes then 5 ml of pH 7.5 aq. phosphate buffer and ethylacetate is added. The organic layer is washed with water, dried and concentrated to give the crude vinyl sulfide. Chromatography on 13 g of silica gel and elution with 45% ethylacetate in benzene gives the pure vinyl sulfide (0.20 g) as a pale yellow gum.
Step O ##STR22##
6-hydroxymethyl-2-(N-carbo-p-nitrobenzyloxy-β-aminoethylthio)-3-carbo-p-nitrobenzyloxy-1-carbadethiapen-2-em
The vinyl sulfide (0.29 g, 0.51 mmole) is dissolved in 5 ml of dry dimethyl sulfoxide containing 1,5-diazabicyclo[5.4.0]undec-5-ene (0.074 g, 0.49 mmole). The solution is aged at room temperature for 15 minutes and then quenched by addition of 5% aq. potassium dihydrogen phosphate. The product is extracted into ethylacetate, washed with three portions of water, dried and concentrated to give a yellow gum which is chromatographed on 9 g of silica gel. The 45% ethylacetate in benzene fractions are concentrated to give 0.080 g of recovered starting material. The 70% ethyl acetate in benzene fractions afford the pure product (0.081 g) as a yellow gum.
STEP P ##STR23##
A mixture of vinyl sulfide (0.10 g, 0.17 mmole), and 50 mg of 10% Pd/C, and K 2 HPO 4 (40 mg, 0.23 mmole) in dioxane (1 ml), ethanol (1 ml), and deionized water (7 ml) is pressurized to 50 psi with hydrogen. The mixture is shaken or stirred at room temperature for 50 minutes and then it is vented and filtered. The catalyst is washed with 2 ml of 0.1 N pH 7 phosphate buffer. The combined filtrates are concentrated in vacuo to the cloud point and then extracted with ethyl acetate. The water layer is concentrated to about 3 ml and charged on a column of 110 g XAD-2 resin. The column is eluted with fractions monitored by UV. Those fractions with UV absorption at 300 mμ are combined and lyophilized to give the product as a white solid (12.3 mg).
EXAMPLE 2
Step A
1-Carbobenzyloxy-2-carbo-t-butoxy-5-carbomethoxy-3-pyrrolidinone ##STR24##
To an ice-cooled suspension of 11.2 g. (0.10 mole) of potassium tert-butyl alcoholate and 125 ml. of dry toluene is rapidly added a mixture of 70 g. (0.60 mole) of t-butyl acetate and 26.5 g. (0.10 mole) of N-carbobenzyloxy-t-butylglycinate. The resulting suspension is aged for 5 minutes and then a solution of 14.4 g. (0.10 mole) of dimethyl maleate is added dropwise. The brown solution is aged at 0° C. for 20 minutes and then quenched by rapid addition of 25 ml. of glacial acetic acid. The organic solution is washed successively with water 2 portions of solid aqueous sodium carbonate and 2 portions of water, then dried (MgSO 4 ) and evaporated in vacuo to give 30.6 g. of viscous, yellow oil.
The crude product is purified by reacting it with 19 g. (0.11 mole) of Girard's Reagent T (carboxymethyl)trimethylammonium chloride hydrazide) and 12 ml. of glacial acetic acid in 300 ml. of methanol at 55° C. for 2 hours. The solution is concentrated in vacuo. The residue is partitioned between 60 ml. H 2 O and 60 ml. ethyl acetate. The aqueous layer is separated, 60 ml. of diethyl ether is added, and 15 ml. of concentrated hydrochloric acid is added with stirring. After 10 min. of stirring, the layers are separated. The organic phase is washed with water, dried (MgSO 4 ) and evaporated in vacuo to give 15.8 g. of pure pyrrolidinone which slowly solidifies on standing.
Step B
2-Carboxy-3,3-dithiomethyl-5-carbomethoxy-pyrrolidine hydrobromide ##STR25##
The pyrrolidinone (10.0 g, 0.026 mole) is dissolved in 50 ml. of liquid methyl mercaptan. To this refluxing solution (6°) is added dropwise a solution of 2 g. of hydrogen bromide in 8 ml. of glacial acetic acid. The resulting solution is stirred for 12 hours and then concentrated in vacuo. The oily residue is dissolved in 10 ml. of methanol. With stirring, 400 ml. of ether is added to the methanol solution. The oil which separates is allowed to settle and the solvent is removed by decantation. This dissolution-precipitation procedure is repeated once and then the oil is pumped to constant weight to give 10.78 g of foamy, tan solid.
Step B 1
2-Carboxy-3,3-dithiomethyl-5-carbomethoxy-1-(t-butoxycarbonylacetyl)pyrrolidine ##STR26##
To a stirred suspension of 4.53 g. of amino acid and 2.6 g. of potassium t-butyl malonate in 70 ml. methylene chloride is added a solution of 2.70 g. of N,N'-dicyclohexylcarbodiimide. The suspension is stirred for 20 minutes, then cooled to 0° C. and filtered. The filtrate is washed with 1 N aqueous hydrochloric acid and then the product is extracted into saturated aqueous bicarbonate solution. The basic layer is carefully acidified with 2 N hydrochloric acid and the product extracted into 2 portions of methylene chloride. The combined organic extracts are dried over MgSO and concentrated in vacuo to give 1.48 g. of crude prodduct. Purification is affected by chromatography on 40 g. of silica gel. The product which is contained in the fractions eluted with 1% acetic acid in ethyl acetate amounts to 0.66 g. of colorless oil.
Step C
2-Carboxy-3,3-dithiobenzyl-5-carbomethoxy-1-(t-butoxycarbonylacetyl)pyrrolidine ##STR27##
To an ice-cooled solution of 4.17 g. (0.01 mole) of amino acid and 1.6 g. (0.01 mole) of t-butyl hydrogen malonate in 70 ml. of methylene chloride is added a solution of 2.06 g. (0.01 mole) of N,N'-dicyclohexylcarbodiimide in 8 ml. of methylene chloride. The resulting suspension is warmed to room temperature and aged for 2 hours and then filtered. The filtrate is washed with 2 N hydrochloric acid, dried over MgSO 4 , and concentrated in vacuo to an oil. The crude product is chromatographed on 200 g. of silica gel, after a forerun of 1% acetic acid in methylene chloride the product is eluted with 1% acetic acid in ethyl acetate. Concentration gives the product (mixture of isomers) as a foamy white solid (3.8 g).
Step D
2-Carboxy-3,3-dithiobenzyl-6,8-dioxo-1-azabicyclo[3.3.0]octane ##STR28##
To an ice-cooled solution of the pyrrolidine (5.03 g, 9.0 mmole) in 100 ml of methanol is added 2.02 g (18.0 mmole) of potassium-t-butyl alcoholate. The solution is aged at room temperature for 45 minutes and then heated to reflux for 30 minutes. The solution is concentrated in vacuo. The residue is treated first with 2 N aq. hydrochloric acid and then extracted with three portions of methylene chloride. The combined organic extracts are dried over MgSO 4 and concentrated to an orange gum which is dissolved in 100 ml of toluene and refluxed for 2.5 hours. Concentration in vacuo gives 4.2 g of crude product which is purified by chromatography on silica gel (130 g). The product which is eluted with 1% acetic acid in ethyl acetate amounts to 3.96 g of foamy, yellow solid.
EXAMPLE 3 ##STR29##
Preparation of Pharmaceutical Compositions
One such unit dosage form comprises a blend of 120 mg. of 1 with 20 mg. of lactose and 5 mg. of magnesium stearate which is placed in a No. 3 gelatin capsule. Similarly, by employing more of the active ingredient and less lactose, other dosage forms can be prepared; should it be necessary to mix more than 145 mg. of ingredients together, larger capsules may be employed. Equivalently, compressed tablets and pills can be prepared. The following examples are further illustrative of the preparation of pharmaceutical formulations:
______________________________________TABLET PER TABLET______________________________________Compound 1 ˜ 125 mg.Dicalcium Phosphate 200 mg.Cornstarch, U.S.P. 6 mg.Lactose, U.S.P. 200 mg.Magnesium Stearate 270 mg.______________________________________
The above ingredients are combined and the mixture is compressed into tablets, approximately 0.5 inch in diameter, each weighing 800 mg. | Diclosed is a process for preparing the antibiotic 6-hydroxymethyl-2-(β-aminoethylthio)-1-carbadethiapen-2-em-3-carboxylic acid (I) ##STR1## and its pharmaceutically acceptable salt and ester derivatives. | 2 |
BACKGROUND OF THE INVENTION
This invention relates to an arrangement for service, maintenance and installation at subsea locations by means of which an operator or diver can be located within a bell and from the interior of the bell operate devices for working at depths within the sea, for example, on wells in offshore petroleum recovery arrangements.
More and more in recent years there has been an increase in offshore gas and petroleum well drilling and recovery and interest increases more and more both in terms of the area where such drilling can occur and the water depths at which these can occur.
Methods had originally been used at shallower depths where divers of various types within the water could provide the maintenance and manipulation and connecting steps necessary during preparation of a well. However, this provides severe limits on the time within which a diver may operate and causes considerable mental and physiological strain on the diver.
Therefore, automatic or remote or robot devices have been used in order to avoid the need for divers, they being controlled from the surface. However, it is important that man be located at the place where maintenance and construction or fabrication is being performed so as to deal with any trouble areas that occur and also to better analyze the situation.
This has led in most recent years to the use of manned bells, preferably atmospheric type, so that decompression is not a problem that needs to be contended with, since it creates problems even when saturation diving is used and also creates enormous expenses.
Apparatus is disclosed in U.S. Pat. No. 3,302,709 for working at an underwater well base. This arrangement provides for automatic devices which use guide lines from a surface location to the subsea well for directing the devices.
A salvaging method is disclosed in U.S. Pat. No. 1,469,574 which includes the use of parallel spaced apart guide rods extending from a salvaging ship to a sunken vessel and along which a frame is guided from the surface to the sunken vessel. The frame has the salvaging mechanism such as locating, cutting, and grappling mechanisms mounted thereon.
A diver controlled salvage bell is disclosed in U.S. Pat. No. 2,320,696, from which the operator within the bell may control movement of the bell with respect to a sunken ship and the diver may, for example, move the device laterally or vertically to position it while it is under water.
U.S. Pat. No. 3,851,491 discloses an underwater bell chamber provided with arms and grippers. The bell is guided along the guide wires from the surface to the subsea well by moving along the guide wires. The grippers are controlled by an operator within the chamber in order to stop and lock movement of the chamber by gripping the guide wires.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide an improved manned submersible bell arrangement from which operators within the bell can view and operate upon devices located at the subsea surface. It is another object to provide such apparatus wherein access is provided to all sides to be worked upon during a single dive.
The present invention provides a bell assembly which is normally negatively buoyant and which includes a bell. Frame means are provided which are movable vertically beneath the sea surface between an upward position and a lower position, the latter being above the subsea surface and at which the frame can be temporarily made stationary. The frame has a path defining portion. Bell moving means are further provided and connected between the bell assembly and the frame means. The bell moving means is used to move the bell between a lower position adjacent the subsea surface and an upper position adjacent the frame means. Mounting means are provided for mounting the bell assembly for movement along such path.
In the more detailed aspects of the present invention a blowout preventer is arranged at the subsea bed or surface and is surrounded by a frame constructed of four vertical members which may be one-piece members or may be a number of members coupled together by flanges at the ends thereof. Guide wires project from each of the vertical members to the surface. A sliding framework is provided and winched from the surface to the guide frame and back up again. The bell assembly is connected to the sliding framework. The sliding framework is slidably connected to all four guide wires which it surrounds and has an offset portion from which the bell depends so as to provide that the bell can be lowered to a vertical position below the top of the guide frame.
Initially, the bell which is normally buoyant and the ballast weight connected to the bottom of it in a movable manner are winched securely and compactly against one another adjacent the sliding framework. This assembly is then lowered down the existing guide wires and is landed on the guide frame. The surface operator then slacks off on the lift line assembly. The entire assembly is designed to be near neutral buoyancy.
Upon landing on the guide frame the operator inside of the bell actuates the ballast weight winch which lowers the negatively buoyant bell/ballast weight combination to the subsea surface or sea bed. When the bottom is reached the bell operator actuates the bell winch permitting the buoyant bell to be adjusted to any desired vertical position between the bottom at which the bell ballast is located and the upper position at which is located the winch mounted on the lower end of the sliding framework.
The manipulative movement and the slide wire framework geometry are such that it is possible for the bell operator to reach any point on the blowout preventer face for servicing. If another surface of the blowout preventer requires servicing, the carriage is moved about the annular framework to provide access to the particular surface of the blowout preventer to be operated on.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side elevational and a partial sectional view illustrating the bell assembly in a first position with respect to a BOP near the subsea surface.
FIG. 2 is a side elevational view similar to FIG. 1 illustrating the bell as the subsea surface.
FIG. 3 is a side elevational view similar to the previous figures illustrating the bell in a position between the subsea surface and the sliding framework.
FIG. 4 is a front elevational view with the bell shown in the same position as in FIG. 3.
FIG. 5 is a perspective view of the annular framework, carriage, and bell assembly.
FIG. 6 is an enlarged partial sectional view of the carriage and the bell assembly.
FIG. 7 is an enlarged broken away perspective view of the track assembly.
FIG. 8 is an enlarged perspective view of the carriage.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
In FIG. 1, there is generally indicated a blowout preventer (BOP) 10, which is used during drilling to control pressures and it is seated at the subsea surface S in an arrangement which is known in the art. Blowout preventers are standard in this art and generally include elements for closing around the operating tools to seal against high pressure and have a series of valves to allow for control. BOP 10 is surrounded by a guide generally indicated at 12 which includes four vertical rigid guide members 30 arranged at the corners of a square to surround BOP 10. The frame includes cross members 32 and, at least at the lower end, is attached to the BOP at 36 for stability.
A system of guide wires 14 is provided from the sea surface down to the BOP guide 12, one guide wire for each vertical element of the guide, so as to provide guiding means for the transportation from the sea surface to the BOP 10 and back up again for the installation and maintenance of equipment which are needed during drilling.
A sliding annular framework generally indicated at 16 is provided on the four guide wires 38 of system 14. The bell 18 is connected to the sliding framework 16 in a manner which will be described in more detail below.
The sliding framework 16 is lowered down the guide wires and is provided with a horizontally extending annular portion from which the bell 18 depends so that bell 18 is located outside of the area defined by connecting the imaginary lines between adjacent guide wires. The bell 18 is normally buoyant, that is, has positive buoyance, and is provided with a ballast weight 20 which, together with bell 18, comprises the bell assembly. The bell assembly 18, 20 is winched securely and compactly together and adjacent sliding framework 16 at the sea surface. This assembly is then lowered down the existing guide wires and landed on top of the guide 12. The surface operator at this time slacks off on lift lines 88 and 89. The entire bell assembly is designed to be near neutral but negatively buoyant.
Upon landing on the guide 12, the bell operator actuates the ballast weight winch 24 to lower the negatively buoyant bell 18/ballast weight 20 assembly to the subsea surface as shown in FIG. 2. Once attaining the bottom, the bell operator actuates the bell winch 26 to permit the buoyant bell 18 to be adjusted to any desired vertical location between the subsea surface and the bottom end of the sliding framework as shown in FIGS. 3 and 4. A manipulator device 28 is provided on the side of the bell 18 facing the BOP 10 in order to permit the operator to operate and make adjustments and the like to the equipment.
The frame 16 is annular in form so that it surrounds the guide wire system 14 and the guide structure 12 completely and is provided with a track. Annular frame 16 has a carriage 17 mounted therewith for movement along an annular track so that by movement of the carriage along the track the bell can be moved in a manner which provides 360° coverage of the BOP 10 by an operator within the bell during a single dive without the need for resurfacing. The carriage itself is provided with equipment, gears, motors, winches, and the like to provide for operational movement of the bell. The carriage can be driven hydraulically or electrically and controlled from within the bell.
Now that the device in general has been described, a more detailed description of the construction and operation of the various elements thereof will be provided.
A guide system is provided containing a guide structure or frame 12 at the bottom and which surrounds the BOP 10, as well as the guide wire system 14 attached to the top of the guide 12 which sits on the bottom and surrounds the BOP. This guide system includes vertical guide members 30 which can be of one piece but, for convenience, might also be constructed in sections as shown so that they can be constructed of any length desired depending upon the structure which they are to surround. Between adjacent vertical guide supports 30 are a plurality of horizontal guide struts 32 to provide rigidity to the structure which is basically a framework. Pads 34 are provided at the lower end of the vertical supports 30 to provide for a distribution of the downward pressure on the sea bed and prevent the guides 30 from sinking into the sea bed. Support struts 36 are connected between the lower end of the BOP and the guide 12 in order to provide further support to both structures which are thereby connected together.
The guide wire system 14 includes four guide wires 38, each of which is connected to a respective vertical support 30 of the guide structure and which extends to the surface in a manner which is known in the art. These four guide wires 38 are connected to the frame structure 12 in a suitable manner and provide a guide system for allowing various devices, machinery and equipment to be raised and lowered in connection with the well drilling operation.
A sliding framework 16 is provided for movement on the guide wires 38 and the sliding framework 16 is constructed in the following manner. It includes four lower sliding guides 40 and four upper sliding guides 42 which can move over the guide wires 38. The guide wires 38 slip through the guides 40, 42 upon movement of the sliding framework 16.
The lower sliding guides 40 are connected together by the inner portion 41 of lower annular member 44 and the upper sliding guides 42 are connected together by an upper annular beam 46.
The lower annular member 44 includes an annular plate 45 disposed in a substantially horizontal plane and which has suspended therefrom annular tracks or rails 47 and 48 which are in spaced relationship with respect to one another for guiding and carrying the carriage 17 in a closed loop or circle around the four guide wires 38. Inner rail 47 and outer rail 48 each have a vertical member 47' and 48', respectively, each having one end connected to and suspended from element 45. The other end of each member 47' and 48' has horizontal members 47" and 48", respectively, connected thereto to form rails 47 and 48 in radially spaced relationship with respect to each other and having the free ends of members 47" and 48", respectively, in facing arrangement with respect to each other. The free edges of members 47" and 48" may have vertical lips (not shown) to aid in the formation of annular grooved tracks for guiding carriage 17. The carriage rides on tracks 47 and 48 on portions 47" and 48" and will be described below.
The lower sliding guides 40 are connected to the inner surface of annular horizontal plate 45. The outer surface of horizontal annular plate 45 is connected to vertical plates 49 which extend upwardly therefrom to a point disposed above the upper surface of the horizontal annular plate 45. Radial beams 51 are connected between the tops of upwardly extending plates 49 and sliding guides 40 so that a rigid structure is formed by sliding guides 40, radial beams 51, upstanding plates 49, and horizontal annular plate 45. Gusset plates 53 are also provided to add rigidity to the structure. In addition there are inclined supports 54 which are connected from the outer end of radial beams 51 to the upper sliding guides 42.
Thus, a unitary frame is formed including the upper annular beam 46 to which the upper sliding guides 42 are connected, the inclined beams 54, the radial beams 51, the lower sliding guides 40, and the horizontal annular plate 45.
The bell 18 itself is actually a manned atmospheric chamber which is lowered from a surface vessel. It is intended to be operated at atmospheric pressure although other uses may be made of the device. The bell is provided with a life support system which is self-contained for emergencies. The life support is provided from the surface by means of the umbilical 94 connected to umbilical winch 97 and, in turn, to umbilical 90. The bell chamber, its construction, operation, life support systems and the like, as well as the assemblies related thereto, can be the type of structures disclosed in U.S. Pat. No. 3,851,491.
The bell is constructed so that it is buoyant, that is, has a positive buoyancy, so that if unconnected to other equipment it moves upwardly toward the sea surface. The bell itself includes an outer shell 56 having a hatch 56 for ingress and egress to the life support and working chamber. This hatch 58 can be provided with a window for observation if desired. An actual observation window 60 is provided on the side of the bell which faces the BOP and other such windows can be provided at multiple locations such as at port 62. A penetrator 64 is provided to which the umbilical 90 is connected in order to provide air, electrical connections and communication means as well as other types of information and signals which are needed from the bell to the surface during operation, ascent and descent.
In addition to providing for voice communication, the umbilical provides for television communication and for the sensors and gauges in the bell to transmit indications to the surface so that some of the controls can be operated and maintained and continuous surveillance performed from the surface. The side of the bell facing the BOP is provided with manipulators 28 including extendible manipulating arms 66 pivotally connected to the bell and extensible and rotatable and may have, for example, claw-like grippers 68 at the ends thereof which can grip tools, valves and the like and which can be rotated longitudinally of the arms 66. They can be moved up and down and from side to side. Thus, a complete range of movement is provided for the manipulators 28 so that an operator within the bell chamber can provide maintenance and operation of various devices outside of the bell and located within the guide frame 12 and on the BOP.
The outside of the bell 56 is provided with sliding bell guides 70 for a purpose which will be explained in more detail later. The bell itself is provided at the lower end thereof with a chamber in which is located a winch 72 for a purpose which will also be described below.
There is a ballast weight arrangement 20 which includes a ballast weight 74 which is at least sufficiently heavy to overcome the positive buoyancy of the bell and render it negatively buoyant when the bell and the ballast weight are considered together. The exact amount of this weight needs to be determined for the particular application but should be sufficient so that when the ballast is lowered it will be maintained steady on the subsea surface and will maintain bell guide wires 84 connected with it taut as required and as described further below.
The ballast 74 itself is constructed in such a manner as to include idler rollers or sheaves 76 over which a bell guide wire 84 operates and therefore the idler rollers 76 are easily rotatable. A lifting flange 78 is connected to the ballast 74 by which the ballast is connected to a bell ascent/descent cable 80 which is connected from flange 78 to bell winch 72. The bell winch itself includes a motor and a drum onto which the bell ascent/descent cable 80 is wound or unwound depending upon the direction and rotation of the motor. It should be clear that as the winding process takes place the ballast weight and the bell are moved closer together until they are in the position shown in FIG. 1, at which time the ballast weight is immediately adjacent the bottom of the bell and contacting it. When winch 72 is unwound, the bell and the ballast weight are separated as shown, for example, in FIGS. 3 and 4 in which the ballast weight is located on the subsea surface S and the bell itself has ascended halfway to the sliding framework 16.
The ballast weight winch 24 is connected to the carriage 17 movable along the sliding framework 16 and includes a motor driven drum 82 onto which the bell guide cable 84 is wound. One end of the bell guide cable is connected at 86 to one end of the carriage 17 and the other end to the winch 24 at the opposite end of the carriage 17. The bell guide cable 84 is anchored at one end at 86, passes downwardly through a first sliding guide 70 on the bell down to the ballast and around first one idler roller or sheave 76 across the ballast and then around the second idler roller or sheave 76 upwardly through the other sliding guide 70 on the bell and then to drum 82. Thus, as the drum 82 is wound or unwound the ballast will ascend or descend accordingly.
The lift system 22 includes lift lines 88 and 89 connected at diametrically opposite points on annular beam 46 by flanges 91 and 93. The umbilical 90 is provided with all of the fluid carrying means required for providing air from the surface to the ball and with communication means for providing voice communication, possibly television communication, and for transporting the various gauge and sensing indications as well as controls between the bell and the surface. The lift system 22 at the surface is connected to a suitable raising and lowering device such as two topside winches and is connected to the sliding framework 16.
With particular reference now to FIGS. 5 and 6, the carriage 17 itself comprises a frame 43 on which are mounted four wheels 50 which ride on tracks 47 and 48 which maintain the wheels in position along the intended path 44 for the carriage 17. Additional wheels may be mounted on frame 43 to aid in carrying carriage 17 along the intended path 44. A motor 52 is provided which may be hydraulically or electrically operated and by means of which are driven rollers 95 which coact with facing surfaces of drive tracks 96 located on the underside of plate 45. The drive rollers 95 and drive tracks 96 can be in the form of a traveling gear mechanism wherein the gears of the drive rollers 96 intermesh with the teeth of tracks 96 so as to readily provide means for driving the carriage to any intended location.
Bell umbilical line 90 is connected between the bell on one hand, and a bell umbilical winch 97 located on the carriage 17, on the other hand. The umbilical winch, which may be driven by an electric or hydraulic motor, operates to maintain proper length in the umbilical cable 90 when the bell is raised or lowered between the frame 16 and the subsea surface S in order that the cable does not get caught or hung up upon movement of the bell. Further, a guide element 98 is connected to the lower portion of carriage 17 which extends below rails 47 and 48 and extends outwardly beyond the outer edge of horizontal member 44 and having a guide eye 99 at its free end for guiding umbilical 90 coming from the support vessel at the sea surface to the umbilical winch 98 located on carriage 17. The guide element 98 guides umbilical 90 so as not to become caught or hung up upon movement of carriage 17 along the circular track during movement on the 360° path. Umbilical 90 further has communication lines 90' which are capable of operating motor 52 and winches 24 and 98 from signals sent from an operator in bell 18 via support vessel or directly from the support vessel.
The operation of the device will now be described.
The sliding framework 16 is lowered down the four guide wires from the topside winches. One manner of constructing and/or using a guide frame and guide wire arrangement somewhat similar to that disclosed herein is disclosed in U.S. Pat. No. 3,302,709, and a similar system is used in the arrangement disclosed in U.S. Pat. No. 3,851,491, while slightly modified arrangements are disclosed in U.S. Pat. Nos. 3,641,777, 3,353,364, and 3,465,531. The bell assembly 18, 20 is winched securely and compactly together adjacent sliding framework 16 topside at the sea surface. This assembly is then lowered down the existing guide wires and landed on top of the guide 12. The surface operator at this time slacks off on the lift line assembly 22.
Upon landing on the guide 12, the bell operator actuates motor 52 to drive carriage 17 along the track until the bell is facing the side of BOP 10 to be serviced. The bell operator then actuates the ballast weight winch 24 to lower the negatively buoyant bell 18/ballast weight 20 assembly to the bottom as shown in FIG. 2. Once attaining the bottom, the bell operator actuates the bell winch 26 to permit the buoyant bell 18 to be adjusted to any desired vertical location between the subsea surface and the lower portion of the sliding framework 16 as shown in FIGS. 3 and 4. A manipulator device 28 of the type known in the prior art, such as device 75 shown in FIGS. 2, 3 and 9-11 in U.S. Pat. No. 3,851,491, or as disclosed in U.S. Pat. Nos. 3,400,541, 3,229,656, and 3,463,226, is provided on the side of the bell 18 facing the BOP 10 in order to permit the operator to operate and make adjustments and the like to the equipment. By appropriate design of the manipulator movement and slide frame geometry, it is possible for the bell operator to reach any point on the BOP face for servicing.
All motors for winches and the like may be hydraulically or electrically driven and each winch may be provided with its own reversible motor.
It will be understood that the above description of the present invention is susceptible to various modifications, changes and adaptations, and the same are intended to be comprehended within the meaning and range of equivalents of the appended claims. | Diving apparatus which includes a bell assembly normally negatively buoyant and including a bell. There is a frame movable vertically beneath the sea surface and having a portion defining a path. Such frame is movable between an upper position and a lower position above the subsea surface at which the frame can be made temporarily stationary. Bell moving apparatus is disposed between the bell assembly and the frame for moving the bell between a lower position adjacent the subsea surface and an upper position adjacent the frame. Apparatus is provided for mounting the bell assembly for movement along such path. | 4 |
BACKGROUND OF THE INVENTION
The a prior art apparatus used for ironing clothes, for example, has a large pressing plate mounted pivotably to the rear end of a main body thereof so that a garment on an ironing table can be pressed down with the pressing plate actuated for upward and downward movement on a pivot located in the rear end by hand or with the use of a hydraulic cylinder.
Accordingly, the pressing plate of the prior art apparatus moves downward in a vertically extending curve (i.e. about a rotative axi) to come into contact with the ironing table and thus, will press against the garment on the ironing table in slightly unaligned engagement. This causes creases or folds in the garment placed over the ironing table, e.g. in a gathered skirt or a pair of trousers, to become loose during pressing operation although such creases or folds were originally arranged to be straight. This results in double creases or folds or damage to the shape of the skirt or trousers.
Additionally, when the pressing plate is turned backward of the main body in pivotal movement, its bottom faces the operator. As a result, hot air discharged from the pressing plate will blow directly into the face and hands of the operator standing in front of the Apparatus. The working condition for the operator is thus dangerous.
OBJECTS OF THE INVENTION
It is a primary object of the present invention to provide an ironing apparatus in which a pressing plate is substantially vertically moved to and from an ironing table, as constrasted to the conventional pivoting movement, so that clothes can neatly be ironed without any damage to the shapes thereof incorporating folds and creases for gathering and additionally, so that the operator is not exposed to any blast of hot air from the ironing plate. Advantageously, this allows an unskilled operator to operate the apparatus without difficulty.
It is another object of the present invention to provide an ironing apparatus in which a pressing plate has its upper position spaced from an ironing table and is movable backward or laterally for retracting action. Thus, conventional limited movement of the pressing plate is eliminated. This allows an unskilled operator to iron clothes with ease.
It is a further object of the present invention to provide an ironing apparatus which comprises a plurality of ironing tables mounted on the working surface thereof and a single pressing plate movable substantially vertically of the ironing tables and also adapted for rightward and leftward movement so that the working efficiency is improved by concurrently pressing one pressing plate against one of the ironing tables, and preparing another pressing plate for ironing operation on the next ironing table. Thus, the apparatus requires less space for installation with ease of arrangement. A plurality of ironing operations can thus be carried out at the same time in a single machine.
The foregoing objects are attained in the invention which encompasses an ironing apparatus utilized for making gather lines in a skirt, making creases in a garment such as a blouse, a shirt, a pair of trousers, or the like, and smoothing out wrinkles in such garments, which apparatus comprises an ironing table disposed horizontally on the working surface of a main body; a pressing plate disposed above the ironing table in confronting relationship thereto; lifting means for moving the pressing plate vertically to and from the ironing table; a first moving means for moving the pressing plate forward and backward; and a second moving means for moving the pressing plate rightward and leftward so that the pressing plate performs pressing operation in a substantially vertical downard direction without disturbing the shape of the garment. Thus, advantageously, the ironing apparatus can be handled with ease, and does not expose the operator to hot air or steam emanating from the pressing plate.
BRIEF DESCRIPTION OF THE DRAWINGS
The drawings illustrate embodiments of the present invention, in which:
FIG. 1 is an external perspective view of an ironing apparatus;
FIG. 2 is a cross sectional view of the ironing table shown in FIG. 1, as taken along section line 2--2;
FIG. 3 is a plan view of the ironing table shown in FIG. 1;
FIG. 4 is a longitudinal cross sectional view of the ironing apparatus;
FIG. 5 is an external perspective view of an ironing apparatus accordng to another embodiment;
FIG. 6 is a cross sectional view of an ironing table for a sleeve shown in FIG. 5, as taken along section line 6--6;
FIG. 7 is a plan view of the ironing table for a sleeve;
FIG. 8 is a cross sectional view of an ironing table garment body shown in FIG. 5 as taken along section line 8--8;
FIG. 9 is a plan view of the ironing table for a garment body;
FIG. 10 is a partially cut away sectional view of a pressing plate;
FIG. 11 is a partially cut away sectional view of the apparatus shown in FIG. 5; and
FIG. 12 is an explanatory view of a horizontally moving mechanism.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 shows an ironing apparatus for ironing a skirt. The ironing apparatus 1 comprises an ironing table 4 horizontally mounted on the working surface 3 of a main body 2 thereof and a pressing plate 5 mounted above the ironing table 4 for vertically liftable movement.
The ironing table 4 is formed of a hollow shape from metal such as stainless steel and fixedly mounted to the top of a tubular support 6 uprightly mounted on the working surface 3 so that the hollow space thereof can communicate with that of the tubular support 6, as shown in FIGS. 2 and 3. The ironing table 4 has an upper surface which is formed in smooth, arcuate configuration corresponding to the shape of a pressing surface 7 in the bottom of the pressing plate 5 and additionally, has a multiplicity of tiny holes 8 arranged at equal intervals therein.
The ironing table 4 is protected with an air-permeable cover cloth 9 as shown in FIG. 1.
As shown in FIG. 4, there is provided an air flowing line 13 connected to both an air supply blower 10 and an air suction blower 11 disposed in the main body 2 via their respective electro-magnetic valves 12. A steam supply line 15 is connected to a steam supplying device (not shown) via a steam supply port 14 mounted in a lower portion of the apparatus. Both of the supplies are joined to a closing plate 16 fixedly mounted within the support 6 thus to fluidly communicate with the hollow space of the ironing table 4.
Additionally, there is a dispersion plate 17 adapted for the dispersion of steam S discharged from the steam supply line 15. The dispersion plate 17 is mounted in the front of both discharging outlets of the air flowing line 13 and steam supply line 15 so that the flow of steam S can outwardly pass through the tiny holes 8 uniformly.
The pressing plate 5 is also formed of a hollow shape from metal such as stainless steel, while its pressing surface 7 in the bottom is formed into smoothly curved configuration corresponding to the shape of the ironing table 4, and provided with a steam supply line 18 fluidly connected at one end to the hollow space thereof and at the other end to a steam supplying device (not shown) respectively.
The pressing plate 5 incorporates a C-shaped support arm 19 the top end of which is located above the ironing table 4 in such a manner that it is fixedly attached to the lower surface of the top end of the support arm 19 by a plurality of bolts 20 so that it can face downward.
On the other hand, the lower end of the support arm 19 is mounted in the main body 2 which accommodates a lifting cylinder 21 as a lifting means. The pressing plate 5 can thus be moved vertically to and from the ironing table 4 by the lifting cylinder 21.
Additionally, there is a cylinder 22 for forward and backward movement provided as forward and backward moving means in order to move the pressing plate 5 (which is at an upper position spaced upward from the ironing table 4) in the forward and backward directions of the main body 2.
The arrangement of the cylinders 21, 22 relative to the support arm 19 and the main body 2 is as follows:
The main body 2 accommodates a lifting guide 23 fixedly mounted thereto in vertical arrangement. The lifting guide 23 incorporates a lift member 25 mounted for vertical movement by slide blocks 24. A piston rod of the lifting cylinder 21 is joined to the bottom of the lift member 25.
The lower end of the support arm 19 is mounted for forward and backward movement to a longitudinal movement guide 26 on the lift member 25 by slide blocks 27, 27 so that a piston rod of the longitudinal motion cylinder 22 disposed on the lift member 25 can actuate the support arm 19 to move forward and backward.
The lifting cylinder 21 actuates a unit of the pressing plate 5, support arm 19, and lift member 25 to move vertically for upward and downward motion. Then, while the pressing plate 5 is at its upper position, the longitudinal motion cylinder 22 actuates a unit of the pressing plate 5 and support arm 19 to move forward and backward.
There are a main switch 28, a timer switch 29, and a timer 20 for setting a pressing time for the pressing plate 5 and a stand-by time of the same at the rear of the apparatus, each of which is mounted on the front panel of the main body 2 as shown in FIG. 1. Additionally, the pressing plate 5 has a switch box 33 containing an ON switch 31 and an OFF switch 32 for controlling the cylinders 21 and 22 and mounted thereabove.
The first embodiment illustrated is arranged as set forth above and its function will now be described.
When the main switch 28 and timer switch 29 in the front are turned on, every component gets ready to operate.
After a skirt (not shown) for instance is placed over the ironing table 4, the air flowing line 13 is then connected with the air suction blower 11 through switching motion of the electromagnetic valve 12. The suction of the air suction blower 11 thus allows the skirt to remain held by suction to the surface of the ironing table 4. While the gathered skirt is tightly held to the upper surface of the ironing table 4 by means of the suction of the air suction blower 11, its fold lines can be arranged straight in order for preparation.
After that, the ON switch 31 on the switch box 33 is pressed to move the pressing plate 5 forward upto a pressing position on the ironing table 4. The pressing plate 5 then presses against the skirt on the ironing table 4 for a specified period of time, e.g. about 3 seconds, determined by the timer 30 without disturbing the shape of the skirt upon moving vertically in a downward direction toward the ironing table 4.
Then, the air flowing line 13 is disconnected through switching motion of the electromagnetic valve 12. The steam S supplied from the steam supply line 15 is then discharged uniformly through the tiny holes 8 formed in the ironing table 4 so as to steam the skirt at a pressure for a specified time, e.g. about 3 seconds, for the purpose of smoothing wrinkles.
After this action is completed, the pressing plate 5 moved is upward and retracted backward of the apparatus. Simultaneously, the air flowing line 13 is connected to the air supply blower 10 through the directional valve 12. The flow of air (hot or cool) from the air supply blower 10 is discharged through the tiny holes 8 in the ironing table 4 so that the skirt can securely be shaped into a gathered form.
While the pressing plates 5 is kept at its backward position for a specified time, e.g. about 3 seconds, the skirt on the ironing table 4 is turned over. As an unfinished gathered portion of the skirt is tightly held by suction to the upper surface of the ironing table 4, the fold lines in the skirt are arranged straight repeatedly in the same manner above described before ironing.
In case that the timer 30 is not used for manual ironing operation, the timer switch 29 should be kept turned off.
When the ON switch 31 is pressed in such a condition, the pressing plate 5 advances horizontally forward to its pressing position and then vertically downward to press against the ironing table 4. After ironing, the pressing plate 5 moves vertically upward and then retracts horizontally backward to its original position for stopping when the OFF switch 32 is pressed.
As set forth above, the pressing plate 5 moves vertically for pressing operation after having been moved to over the ironing table 4 and its pressing force is downwardly exerted on the ironing table 4 so that it can firmly press against the skirt on the ironing table 4 without spoiling the fold lines in the gathered skirt. Thereby, wrinkles in the skirt are removed with the use of steam S and the skirt is properly ironed while retaining its shape.
Additionally, the pressing plate 5 moves upward and downward with its pressing surface 7 constantly facing downward so that the hot air from the pressing plate 5 is prevented from blowing against the face and hands of an operator. This allows an unskilled operator to easily operate the apparatus without fearing for his safety as would be the case with a conventional pressing plate and particularly, will also provide an improved working condition.
Although the embodiment described above employs the pressing plate 5 which is movable forward and backward (seee arrows "A" in FIGS. 1 and 5), it will be understood that equal effect is possible with a pressing plate movable rightward and leftward (see arrows "B" in FIGS. 1 and 5) of the ironing table 4.
Second Embodiment
FIGS. 5 to 12 illustrate an embodiment in which two ironing tables 4A and 4B are horizontally mounted on the working surface 3 of a main body 2 of the apparatus, in which similar number represents similar member as shown in FIGS. 1-4.
The two ironing tables 4A and 4B are spaced at a specified interval from each other laterally of the working surface 3 of the main body 2, Table 4A is formed in a shape corresponding to a sleeve portion of a garment. Table 4B is formed in a shape corresponding to a body portion of the garment.
Each of the ironing tables 4A and 4B contains a partition 35 which divides the interior space thereof into upper and lower portions, as shown in FIGS. 6 and 8. Particularly as best seen in FIGS. 6 and 8, the lower space is fluidly connected to a steam supply nozzle 36 which is in turn connected by a steam supply line 37 to the steam supply port so that either of the ironing tables 4A and 4B can continuously be heated to a constant degree of temperature by the flow of steam S, as shown in FIGS. 6 and 8.
Specifically according to the second embodiment, mounted on the back of the main body 2 is a lift member 25 actuated by a lifting cylinder 21 for upward and downward movement as shown in FIGS. 11 and 12. The lift member 25 has a lateral moving means 38 mounted to the back thereof for actuating a single pressing plate 5 through an inverted L-shaped support arm 19 to move rightward and leftward.
The lateral moving means 38 is constructed in the following arrangement.
Two of laterally extending guide rails 39, 39 arranged parallel to each other are mounted to the back of the lift member 25. The support arm 19 has two sliding blocks 40 fixedly mounted to the lower end thereof. The sliding blocks 40 are also mounted for sliding movement to the guide rails 39 respectively.
Additionally, the lift member 25 has a follower shaft 41 and a driving shaft 42 mounted respectively in the right and left ends thereof. The shafts 41 and 42 incorporate two sprockets 43 and 44 fitted thereon respectively, between which a chain 45 is fitted at tension. The chain 45 is joined by chain attachments 46 to one of the sliding blocks 40. The driving shaft is driven by a motor 47.
As the chain 39 is driven by the motor 47, the support arm 19 horizontally moves rightward and leftward and thus, the pressing plate 5 advances to a position ralative to either of the ironing tables 4A and 4B.
A pair of stoppers 48 restricting the movement of the support arm 19 are mounted to both the ends of the lift member 25 while another pair of stoppers 49, 49 defining the lower limit of movement of the lift member 25 are mounted in the lower back of the main body 2.
As shown in FIG. 5, a group of foot switches 50 are mounted in the lower end on the working side of the main body 2 to control the air supply of the air supply blower 10, the air suction of the air suction blower 11, and the discharge of steam from the steam supply line 15. Additionally, two pushbutton switches 51 which control the movement of the pressing plate 5 with respect to the upward, downward, rightward, and leftward directions are respectively mounted in both ends of the front sloping portion of the working surface 3.
The operation in the ironing apparatus formed in such an arrangement will now be described. A sleeve of a garment is placed on the ironing table 4A, one of the tables shown in FIG. 5, while a body of the same is placed on the other ironing table 4B in preparation for an ironing operation. One of the foot switches 50 is then pressed and then, the garment is tightly held by suction to the ironing tables 4A and 4B while being kept stretched without wrinkles.
The pressing plate 5 is vertically moved downward to the ironing table 4A (with the sleeve) when one of the pushbutton switches 51 is turned on and presses against the sleeve of the garment on the ironing table 4A.
After pressing, the other foot switch 50 is pressed to stop the air suction blower 11. The steam S from a steam supply device (not shown) is uniformly discharged from a multiplicity of tiny holes 8 formed in the upper surface of the ironing table 4A so that the garment can be steamed under pressure for a specified time.
The last one of the foot switches 51 is then pressed to stop the discharge of steam S. The pressing plate 5 is moved vertically upward with its pressing surface facing the ironing table 4A when the other pushbutton switch 51 is turned on. Simultaneously, the air supply blower 10 is actuated to uniformly supply a flow of air through the tiny hole 8 in the upper surface of the ironing table 4A. The air cools the sleeve of the garment and the garment thus remains smooth without wrinkles.
On the other hand, the pressing plate 5 at its upper position is horizontally moved with its pressing surface 7 facing downward to above the ironing table 4B located next to the table 4A. Then, the pressing plate 5 is vertically moved downward to the ironing table 4B for ironing the body of the garment when the pushbutton switch 51 is turned on in the same manner described above.
During a period when the pressing plate 5 presses on the ironing table 4A for ironing the sleeve of the garment, it is possible to place the body of the garment over the ironing table 4B in preparation for ironing. Thus, the single pressing plate 5 can effectively be utilized, which improves workability.
Additionally, the pressing plate 5 moves with its pressing surface facing downward so that hot air therefrom is prevented from blowing directly against the face or hands of an operator who can thus carry out ironing under a safe working condition.
Furthermore, according to this invention, a plurality of ironing tables, not limited to the two ironing tables 4A and 4B of the embodiment, are successively attachable of distinct shape corresponding to each part of the garment to be ironed. It is thus possible to carry out ironing of e.g. a sleeve and a body of a garment at a time on one single ironing apparatus. | An ironing apparatus used for making gather lines in a skirt, making creases in a garment such as a blouse, a shirt, or a pair of trousers, and smoothing out wrinkles in the trousers comprises an ironing table disposed horizontally on the working surface of a main body thereof, a pressing plate disposed opposite to and above the ironing table, and a lifting device for moving the pressing plate vertically to and from the ironing table. It further includes forward and backward and rightward and leftward moving apparatus so that the pressing plate can perform ironing through pressing in a vertical direction without disturbing the shape of the garment. Advantageously, the apparatus can thus be handled with ease and additionally, can protect an operator from receiving a blast of hot air emanating the pressing plate. The pressing plate is defined by a C-shaped support arm, the top end of which is located above the ironing table. | 3 |
BACKGROUND OF THE INVENTION
This invention relates to an abrasive body and more particularly to an abrasive body which can be used as a tool insert.
Composite abrasive compacts are products used extensively as inserts for abrasive tools such as drill bits. Such composite abrasive compacts comprise an abrasive compact layer bonded to a cemented carbide support. The abrasive compact will typically be a diamond abrasive compact, also known as polycrystalline diamond or PCD, or a cubic boron nitride compact, also known as polycrystalline CBN or PCBN.
Composite abrasive compacts are manufactured under elevated temperature and pressure conditions. e.g. diamond or cubic boron nitride synthesis conditions.
As it is known that PCD composite compacts contain considerable residual stresses as a result of the high temperature/high pressure conditions used in their manufacture. Further, methods of mounting such compacts into drill bits, for example press fitting or brazing, can modify the stress distributions in the compacts. Additional stresses are imposed on the compacts during their use in applications such as drilling. Stresses may be introduced into the interface between the abrasive compact layer and the cemented carbide support. These stresses may be reduced or modified by providing a recess which extends into the cemented carbide support from the compact/carbide interface and which is filled with the abrasive compact. In the prior art, the recess has taken various shapes such as a plurality of concentric rings, a V-shaped recess, a cross-shaped recess, and a recess which incorporates a number of steps. A purpose in most of such designs is to reinforce and support the cutting edge by providing overall rigidity for the composite compacts.
U.S. Pat. No. 5,472,376 describes a tool component comprising an abrasive compact layer bonded to a cemented carbide substrate along an interface. A recess extends from the interface into the substrate and is filled with abrasive compact. The recess has a stepped configuration and is located entirely within the carbide substrate.
EP 356097 describes a tool insert comprising an abrasive compact bonded to a cemented carbide substrate. The abrasive compact is located in a recess formed in the substrate. The abrasive compact has a top surface which provides a cutting edge for the tool insert, a bottom surface complimentary to the base of the recess and a side surface at least partially located in the recess, the portion of the side surface located in the recess being complimentary to the side of the recess. The side surfaces may be sloping.
SUMMARY OF THE INVENTION
According to the present invention, an abrasive body, for use, for example, as a tool insert, comprises an abrasive layer bonded to a substrate along an interface and at least one strip-like abrasive projection extending from the interface into the substrate, the projection having a profile which includes a substantially flat central portion and surfaces to either side thereof which slope towards the interface.
More than one strip-like projection may be provided. Such projection or projections may extend from one peripheral surface of the abrasive body to an opposite peripheral surface. The projection or projections preferably have a surface coincident with a peripheral surface of the body.
In another form of the invention, three parallel strip-like projections are provided, the inner projection having a width greater than that of the outer projections.
In yet another form of the invention, the strip-like projection has an essentially U-form in plan. Preferably, the limbs of the U have ends coincident with an outer surface of the body.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a plan view of a first embodiment of the invention,
FIG. 2 is a section along the line 2 — 2 of FIG. 1,
FIG. 3 is a section along the line 3 — 3 of FIG. 1,
FIG. 4 is a plan view of a further embodiment of the invention,
FIG. 5 is a section along the line 5 — 5 of FIG. 4,
FIG. 6 is a section along the line 6 — 6 of FIG. 4, and
FIG. 7 is a sectional side view of a further embodiment of the invention.
DESCRIPTION OF EMBODIMENTS
The abrasive body may have various shapes, but is preferably right circular cylindrical.
The substrate layer will typically be a cemented carbide substrate layer. The cemented carbide of the substrate may be any known in the art such as cemented titanium carbide, cemented tungsten carbide, cemented tantalum carbide, cemented molybdenum carbide, or mixtures thereof. As is known, such cemented carbides will typically have a binder content of 3 to 30% by mass. The metal binder will typically be cobalt, iron or nickel or an alloy containing one or more of these metals.
The abrasive layer will generally be an abrasive compact layer or a layer of diamond produced by chemical vapour deposition (CVD). When the abrasive layer is an abrasive compact layer, it will preferably be a diamond compact layer or a cubic boron nitride compact layer.
A first embodiment of the invention will now be described with reference to FIGS. 1 to 3 . Referring to these figures, there is shown an abrasive body comprising an abrasive compact layer 10 bonded to a substrate 12 , generally a cemented carbide substrate, along an interface 14 (see FIG. 2 ). The top surface 16 of the layer 10 provides an abrasive surface for the body and the peripheral edge 18 provides a cutting edge, remote from the interface. The interface 14 has portions 14 a and 14 b which slope relative to the surface 16 and central portions 14 c and 14 d which are parallel to this surface. All these portions of the interface 14 may, in an alternative embodiment, be parallel to the surface 16 .
The abrasive body is characterised, in particular, by the provision of three strip-like projections 20 of abrasive compact which extend from the interface 14 into the substrate 12 . These projections 20 extend from one peripheral side surface of the abrasive body to an opposite peripheral side surface. Thus, each projection has a surface identified as 22 and 24 coincident with a peripheral side surface of the abrasive body.
The profile i.e. the longitudinal cross-sectional shape, of the strips is best illustrated by FIG. 3 . Referring to this figure, it will not noted that the profile is such that there is a central flat section identified as 26 and surfaces 28 , 30 to either side of the central section. The surfaces 28 , 30 slope from the central section 26 to the interface 14 .
It will be noted from FIGS. 1 and 2 that the width in plan of the central strip-like projection is greater than that of the outer strip-like projections. This is a preferred configuration. Other configurations, e.g. in which the widths are the same, are possible.
A second embodiment of the invention will now be described with reference to FIGS. 4 to 6 . Referring to these figures, an abrasive body comprises an abrasive compact 100 bonded to a substrate 102 , particularly a cemented carbide substrate, along an interface 104 . The surface 106 of the abrasive compact layer 100 provides an abrasive surface for the body, while the peripheral edge 108 provides a cutting edge, remote from the interface.
An abrasive compact projection 110 extends from the interface 104 into the substrate 102 . This projection has an essentially U-shape in plan, as can be seen from FIG. 5 . The limbs of the U extend to the outer surface 112 of the abrasive body. Thus, the limbs have edge surfaces 114 coincident with the outer surface 112 of the body.
The profile of the projection 110 is illustrated from different directions by FIGS. 5 and 6. It will be noted from these figures that the profile is such that there is a central flat section 116 and surfaces 118 which slope from the central section 116 to the interface 104 .
The abrasive bodies described above may be made by methods known in the art. Generally this will involve providing a cylindrical shaped cemented carbide body having a recess, to receive the components necessary to make an abrasive compact, formed in one end thereof. An example of such a body, to produce an abrasive body of FIGS. 1 to 3 , is shown in FIG. 7 . Referring to this figure, a cemented carbide body 60 is of right-circular cylindrical shape having flat ends 62 and 64 . A recess 66 is provided in the end 62 . This recess is filled with the components necessary to make an abrasive compact. The thus produced unbonded assembly is placed in the reaction zone of a conventional high temperature/high pressure apparatus to form an abrasive compact of the components which bonds to the body 60 . The abrasive body illustrated by FIGS. 1 to 3 is produced by simply removing the sides of the body 60 , as illustrated by the dotted lines. However, the bonded body which is recovered from the reaction zone after compact formation and without removal of the carbide sides, may be used as a tool insert itself, and forms another aspect of the invention. In this form of the insert, the edge 70 will provide the cutting edge. This edge is likely to wear away fairly rapidly until the abrasive compact edge 72 is reached. Thereafter it is this edge 72 which provides the cutting edge for the component.
The provision of the strip-like projections in the abrasive bodies of the invention result in an effective reinforcement and support for the cutting edge by providing overall rigidity for the bodies. Further, in use the cutting edges in the regions of the surfaces 22 , 24 of the projection for the FIGS. 1 to 3 embodiment and in the region of the surfaces 114 of the projection for the
FIGS. 4 to 6 embodiment will be employed. The extra abrasive available in these regions increases effectiveness of the abrasive action of the body. | An abrasive body which includes an abrasive layer bonded to a substrate along an interface and at least one strip-like projection extending from the interface into the substrate. The projection has a profile which includes a substantially flat central portion and connecting surfaces to either side of the central section. The surface is sloped from the central section to the interface. | 4 |
BACKGROUND OF THE INVENTION
The present invention is related generally to filters and more specifically to industrial filters for removing debris from a fluid path.
During the construction of large and complex components such as steam generators, heat exchangers, or the like, or any system requiring a large number of pipes, pipe fittings, valves, etc., it is known that various construction materials and tools are often left in the component or system being constructed. Such construction debris may include nuts, bolts, pipe fittings, valve parts, screw drivers, wrenches, or any material or device used in the contruction of the component or system. Operation of the component or system without removing that construction debris may prove extremely detrimental because such debris can puncture or rupture pipes, clog pipes, clog valves, or cause similar problems.
Although industrial filters are well-known and are available in a wide variety of shapes and sizes for performing mechanical as well as chemical types of filtering, the requirements of a filter for removing construction debris are substantially different. A filter for removing construction debris must be sized such that it is capable of removing all debris which may cause damage but must not have an adverse effect on the process being performed. The filter must be further sized such that it will be capable of withstanding deformation by the temperatures, pressures, and fluid velocities to which it will be exposed. Such competing design criteria require new approaches to the design and construction of filters for removing construction debris.
SUMMARY OF THE PRESENT INVENTION
According to one aspect of the present invention, a filter removes debris of a predetermined size from a fluid flowing in a path. The filter has a first face disposed transversely in the fluid path and a second face disposed substantially parallel to the first face but displaced therefrom in the direction of the fluid flow. The first and second faces cooperate to define a plurality of apertures extending through the filter. The apertures are of a size to preclude passage of the debris while presenting a predetermined resistance to the fluid flow. The displacement of the second face from the first face defines the thickness of the filter. The thickness of the filter is sufficient for the filter to resist deformation by the fluid flow without requiring any increase in the predetermined resistance to the fluid flow determined by the size of the apertures.
According to another aspect of the present invention, an annularly-shaped filter removes debris of a predetermined size from a fluid flowing in an annular path. The filter has a first face disposed transversely in the fluid path and a second face disposed substantially parallel to the first face but displaced therefrom in the direction of the fluid flow. The first and second faces cooperate to define a plurality of apertures extending through the filter. The apertures are of a size to preclude passage of the debris while presenting a predetermined resistance to the fluid flow. The displacement of the second face from the first face defines the thickness of the filter. The thickness of the filter is sufficient for the filter to resist deformation by the fluid flow without increasing the predetermined resistance to the fluid flow determined by the size of the apertures.
According to another aspect of the present invention, an annularly shaped filter is comprised of a plurality of abutting arcuate-shaped sections. Each arcuate-shaped section includes an inner portion and an outer portion. The abutment of the adjacent inner portions is staggered with respect to the abutment of the adjacent outer portions thereby providing improved capability in withstanding deformation due to thermal and mechanical loading.
One advantage of the present invention is that once the size of the apertures has been chosen based on considerations such as the size of the debris to be removed from the fluid path and the allowable pressure drop across the filter, a filter can be constructed having any desired strength, i.e., resistance to deformation by the fluid flow, without requiring any further restriction of the fluid flow. Thus, the restriction of the fluid flow is substantially independent of the strength of the filter. Other advantages and benefits of the present invention will become apparent from the description of a preferred embodiment hereinbelow.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 illustrates a portion of a filter constructed according to the teachings of the present invention;
FIG. 2 illustrates three members of the filter illustrated in FIG. 1;
FIG. 3 illustrates a portion of another embodiment of a filter constructed according to the teachings of the present invention;
FIG. 3a illustrates a side view of the filter shown in FIG. 3 with the end member removed;
FIGS. 4 and 5 illustrate portions of other embodiments of filters constructed according to the teachings of the present invention;
FIG. 5a illustrates a top view looking through the filter shown in FIG. 5;
FIG. 6 illustrates the location of a filter within a steam generator;
FIG. 6a illustrates one example of an annularly-shaped filter constructed according to the teachings of the present invention located in an annularly-shaped downcomer of the steam generator shown in FIG. 6;
FIG. 7 illustrates a cross-sectional view of the steam generator and annularly-shaped filter shown in FIG. 6A; and
FIG. 8 illustrates another orientation of the filter shown in FIG. 7.
DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1 illustrates a portion of a filter 10 constructed according to the teachings of the present invention. The filter portion 10 is constructed of a first group of substantially parallel members 12, 13, 14, 15, 16, and 17 and a second group of substantially parallel members 19, 20, 21, 22, and 23 disposed proximate to the first group of members 12 through 17. The second group of members 19 through 23 is oriented at an angle with respect to the first group of members 12 through 17. The angle of orientation shown in FIG. 1 is ninety degrees such that the members 12 through 17 of the first group cooperate with the members 19 through 23 of the second group to establish a rectangular pattern. The filter portion 10 shown in FIG. 1 is incomplete in that additional members would be added to the second group of substantially parallel members 19 through 23 in order to complete the rectangular pattern along the length of each of the members 12 through 17 of the first group of members. Clearly, a filter of any dimension can be provided by adding additional members to the first and second groups of members.
The filter portion 10 illustrated in FIG. 1 may be constructed of commercially available prefabricated deck grating having a typical thickness of, for example, one-tenth of an inch and a typical height X, Y of, for example, two inches. The spacing A between each of the members 12 through 17 of the first group of members and the spacing B between each of the members 19 through 23 of the second group of members determines the size of the apertures of the filter 10 and thus the size of the debris which the filter 10 will preclude.
In one embodiment, the spacing A between each of the members 12 through 17 of the first group of members is approximately nine-tenths of an inch and the spacing B between each of the members 19 through 23 of the second group of members is approximately three-tenths of an inch. With such a filter disposed transversely in a fluid path, tools such as screwdrivers, wrenches, etc., and construction materials such a nuts, bolts, piping, pipe fittings, valve pieces, or anything left during construction having a size greater than nine-tenths of an inch by three-tenths of an inch will be precluded from continuing further through the fluid path by the filter portion 10. Such a filter 10 nevertheless has an open area of approximately sixty-five percent such that the restriction of the fluid flow is kept to a minimum.
An important feature of the present invention is the design of the filter 10 shown in FIG. 1 which has a high percentage of open area yet permits a filter having any desired resistance to deformation by the fluid flow to be constructed without further restriction of the fluid flow. That is accomplished by increasing the height X of each of the members 12 through 17 of the first group of members and increasing the height Y of each of the members 19 through 23 of the second group of members. By increasing the dimensions X and Y, the strength of the filter portion 10 is increased with respect to the direction of fluid flow indicated by arrow 25. This increase in strength increases the resistance to deformation by the fluid flow. This increase in strength, or resistance to deformation by the fluid flow, is achieved without decreasing the size of the apertures or the number of the apertures. Thus, once the size of the apertures has been determined based on the size of the debris to be precluded and the allowable pressure drop across the filter, a filter can be constructed having any desired strength without any further restriction of the fluid flow.
The orientation of the members 12 through 17 of the first group of members with respect to the members 19 through 23 of the second group of members is maintained by appropriate interconnection of the members. In FIG. 2 wherein like components have the same reference numerals, the first member 19 of the second group of members is illustrated. The first member 19 of the second group of members has the first member 12 and the last member 17 of the first group of members welded thereto at opposite ends. The first member 19 of the second group of members is provided with four rectangular notches 27, 28, 29, and 30 sized to receive the remainder of the members 13 through 16 of the first group of members. Each of the notches 27 through 30 is deep enough to permit welding of the members 13 through 16 in their respective notch. In the embodiment described above, each of the notches 27 through 30 would be approximately one-tenth of an inch wide and one-quarter inch deep. By welding each of the other members 20 through 23 of the second group of members to the first member 12 and last member 17 of the first group of members, and by providing each of the members 20 through 23 of the second group of members with notches for receiving the remaining members 13 through 16 of the first group of members, an extremely rigid and strong filter 10 is provided.
There are numerous embodiments of the present invention wherein a filter has a design such that any desired resistance to deformation by the fluid flow can be achieved without further restriction of the fluid flow. Other contemplated embodiments are illustrated in FIGS. 3, 4, and 5.
In FIG. 3, the members 19 through 23 of the second group of substantially parallel members are replaced by chevron-shaped members 32, 33, 34, and 35. The chevron-shaped members 32 through 35 have the first member 12 of the first group of members welded at one end thereof. The last member 17 of the first group of members is welded to the opposite end (not shown) of each of the chevron-shaped members 32 through 35. Each of the chevron-shaped members 32 through 35 has an opening therethrough for receiving the remaining members 13 through 16 (15 and 16 not shown). Each of the members 13 through 16 may be welded at their intersection with each of the chevron-shaped members 32 through 35. The filter shown in FIG. 3 exhibits the same characteristic as the filter shown in FIG. 1 in that the strength of the filter may be increased without any further restriction of the fluid flow. That can be achieved by increasing the dimension X of the first group of members and the dimension Y of the second group of members.
The filter shown in FIG. 3 has a further advantage over the filter illustrated in FIG. 1. FIG. 3a illustrates a side view of the filter shown in FIG. 3 with the first member 12 of the first group of members removed. As can be seen from FIG. 3a, the chevron-shaped sections 32 through 35 are spaced such that there are no open straight axial paths through the filter. The chevron-shaped sections 32 through 35 thus cooperate with one another to preclude the passage of rod-shaped debris 37. The filter shown in FIG. 3 precludes passage of the same debris as the filter shown in FIG. 1 and additionally precludes passage of debris such as scewdrivers, rulers, pencils, or the like which approach the filter perpendicularly as shown by the rod-shaped debris 37 in FIG. 3a. The preclusion of rod-shaped debris is achieved without requiring any further restriction of the fluid flow.
Another embodiment of the present is shown in FIG. 4. In FIG. 4 the chevron-shaped members 32 through 35 are replaced by compound chevron-shaped members 39, 40, 41, 42, 43, and 44. The compound chevron-shaped members 39 through 44 are connected to the members 12 through 16 of the first group of members in the same manner as described above in conjunction with FIG. 3. The filter illustrated in FIG. 4 operates in the same manner as discussed above in conjunction with FIG. 3 with the exception that the compound chevron-shaped members 39 through 44 provide additional filtering action against rod-shaped debris provided that the compound chevron-shaped members 39 through 44 are spaced such that no open straight axial path through the filter exists.
Yet another embodiment of the present invention is illustrated in FIG. 5. In FIG. 5 a first plate 46 is provided with a plurality of apertures 48. The filter formed by the first perforated plate 46 has the same characteristic of the filters previously described, i.e., any desired resistance to deformation by the fluid flow may be achieved by increasing the thickness T of the perforated plate 46 without further restricting the fluid flow.
As shown in FIG. 5, it may be desirable to add a second plate 50 having a plurality of apertures 52 therethrough. The orientation of the apertures 48 of the first plate 46 with respect to the apertures 52 of the second plate 50 determines the amount of additional filtering. One predetermined relationship between the apertures 48 of the first plate 46 and the apertures 52 of the second plate 50 is shown in FIG. 5a.
One anticipated environment wherein a filter constructed according to the teachings of the present invention may be used is a steam generator 54 of the type illustrated in FIG. 6. The steam generator 54 is a heat exchanger wherein a superheated liquid under high pressure enters the bottom of the steam generator 54 and circulates through a plurality of steam generator tubes (not shown). The space between the steam generator tubes is filled with water. As the superheated liquid passes through the steam generator tubes the water between the tubes absorbs heat, vaporizes, and rises to the top of the steam generator 54. After the heat energy in the steam has been extracted, the steam recondenses and flows as liquid water down an anular downcomer 56 located around the outer periphery of the steam generator 54 as shown in FIGS. 6a and 7.
In FIG. 6a the annular filter 58 is of the rectangular-type shown in FIG. 1. However, the filter 58 could be of the chevron-type shown in FIG. 3, the compound chevron-type shown in FIG. 4 or the perforated plate-type shown in FIG. 5. The filter 58 extends completely around the inner periphery of the steam generator 54 but is shown partially broken away in FIG. 6a to illustrate triangular supports 60 and 61. A sufficient number of such triangular supports are provided to support the annular filter 58.
The annular downcomer 56 in one embodiment is approximately twelve inches wide at the location where the filter 58 is positioned. The annularly-shaped filter 58 is comprised of twenty-four six-inch wide arcuate-shaped sections, four of which, 64, 65, 66, and 67 are illustrated in FIG. 6a. The arcuate-shaped sections are constructed and positioned such that the abutment of adjacent outer arcuate-shaped sections 64 and 66 is staggered with respect to the abutment of adjacent inner arcuate-shaped sections 65 and 67. This staggered relationship provides an improved capability in withstanding deformation due to thermal and mechanical loading.
The dimension of the apertures of the filter 58 is chosen by the designer depending upon the spacing between the steam generator tubes. Thus, the annular downcomer 56 forms a primary fluid path and the spacing between the plurality of steam generator tubes forms a plurality of secondary fluid paths. The spacing between steam generator tubes may vary from approximately three-tenths of an inch to four-tenths of an inch. Typical debris that has been found to damage the steam generator tubes or clog the spacing between steam generator tubes includes a portion of a baffle plate, a coil spring eight and one-half inches long and one and one-quarter inches in diameter, and a connection pin two and one-quarter inches long and one inch in diameter. Thus, the apertures of the filter 58 would be sized accordingly to prevent passage of debris capable of damaging the steam generator tubes.
The filter 58 shown in the steam generator 54 is located in a position such that the filter 58 may be periodically cleaned to remove the accumulated debris. It is also desirable to position the filter 58 such that existing steam generators 54 may be retrofit with such a filter. The filter 58 is constructed of any material compatable with the internals of the steam generator 54 such as carbon steel and is capable of withstanding the environment within the steam generator 54, e.g., temperatures in excess of 500° F. (260° C.) and pressures on one thousand pounds per square inch.
It is anticipated that in providing a filter 58 as a retrofit item, the shape and orientation of the filter 58 will have to be adjusted for different types of steam generators Shown in FIG. 8 is the filter 58 oriented at an angle with respect to the direction of fluid flow indicated by the arrow 25. Such an orientation requires additional support brackets 69 and 70 to maintain the orientation of the filter 58. Such an orientation presents a greater surface area, flow area, and less pressure drop. It is also anticipated that portions of the filter 58 may be removed, or cut out, as designated generally by the area 72, to allow the filter 58 to be inserted in the annular downcomer 56 despite pipes or supports which may protrude into that area.
Although the filter of the present invention has been described in conjunction with a steam generator, it is anticipated that such a filter will be useful in blowing out pipes in a chemical plant, on trash racks in sewage plants, in filtering debris from water pumped from a river or any similar environment. Thus, it will be understood that many modifications and variations will be readily apparent to those of ordinary skill in the art. This application and the following claims are intended to cover those modifications and variations. | A filter for removing debris of a predetermined size from a fluid path has a first face disposed transversely in the fluid path and a second face disposed substantially parallel to the first face and displaced therefrom in the direction of fluid flow. The displacement of the second face from the first face substantially defines the strength of the filter with respect to deformation by the fluid flow. The first and second faces cooperate to define a plurality of apertures extending through the filter. The apertures are of a size to preclude passage of the debris while presenting a predetermined resistance to the fluid flow. That predetermined resistance is substantially independent of the filter's strength. | 1 |
FIELD OF THE INVENTION
This invention relates generally to the field of battering rams and more particularly to a pneumatically-powered battering ram.
BACKGROUND OF THE INVENTION
For centuries, battering rams have been used to break down gates, walls and doors to force entrance. In ancient times, a battering ram was often nothing more than a heavy wooden beam which was repeatedly pounded by a large group of soldiers against city gates or walls to forcibly gain entrance.
In modern times, variations of the ancient battering ram are still used when circumstances require quick and efficient entrance, such as when a fire fighter must gain access to the interior of a burning building or a law enforcement official must break down a door to apprehend a criminal and/or obtain evidence before it can be destroyed. For example, U.S. Pat. No. 4,681,171 of Kee et al. discloses a battering ram operable by one person which includes a concrete-filled tube with an epoxy resin contact face. U.S. Pat. No. 5,067,237 of Holder discloses yet another type of battering ram which includes a pointed end with barbs to enable the door to be hooked and pulled outward. Sledge hammers have also been employed to achieve the same result.
However, most doors require many blows from such means before entry is achieved. Furthermore, such battering rams are often heavy, cumbersome and difficult to efficiently manipulate. The resultant delay in gaining entry is undesirable for both efficiency and safety reasons. For example, in the law enforcement context, speed and the element of surprise are essential to the safety of law enforcement personnel and the collection and recovery of evidence. Otherwise, while the officers are in the process of breaking down the door, the occupants may arm themselves, destroy evidence, escape, or even fire through the door at the officers attempting to break it down. Of primary importance is the avoidance of casualties. Accordingly, the door must be breached before any of the occupants realize what has happened.
The delay in breaking down the door when using prior art battering rams can be at least partially explained by considering the physics involved in breaking a door with a ram. The ram has a certain mass which is accelerated to a striking velocity by the individuals swinging it. The kinetic energy of the moving mass is applied to the door when the head of the ram contacts the door. Significantly, the force is not applied to the door all at once: the ram comes to a stop during a finite amount of time during which the energy transfer to the door occurs. In part, the speed of the ram determines the total force applied to the door; the speed of the energy transfer determines the peak force on the door. A higher peak force is more effective at breaking doors because for every door there is a threshold force required to begin the process of tearing and ripping that destroys the integrity of the door. Once the force applied is sufficient to start destroying the integrity of the door, it takes very little extra force to complete the job.
The peak force applied to the door is ultimately limited by the velocity with which the ram strikes the door. Increasing the impact velocity of the ram, for the same total energy, is more effective in breaking the door. To bring the total energy available to bear on the door in as short a time as possible requires a higher striking velocity. Thus, there is a need for an improved battering ram which can quickly and efficiently break down doors by providing a higher striking velocity to increase the peak force initially applied to the door.
SUMMARY OF THE INVENTION
Disclosed and claimed herein is a pneumatically-powered battering ram for striking objects such as doors. The battering ram includes a hollow elongated housing having an object-striking end and a second opposed end. The interior of the housing comprises a compartment having a first portion proximate the object-striking end of the battering ram and a second compartment portion proximate the opposed end of the housing. A mass is disposed within the first portion of the compartment. In .the preferred embodiment, the mass is a piston having a head, a connecting rod, and a base with the head of the piston pointed toward the object-striking end of the housing. The second portion of the compartment contains a supply of a compressed gas disposed and sealed therein. Optionally, the compressed gas may be contained in a separate tank which is disposed within the second portion of the compartment. Preferably, the compressed gas is carbon dioxide. A valve means is provided which operates to release a portion of the compressed gas from the second portion of the housing into a charge cavity located between the mass and the second portion of the housing. A trigger mechanism responsive to contact with the object stricken is affixed to the object-striking end of the ram housing. A first end of the trigger mechanism protrudes past the object-striking end of the housing and a second end of the trigger mechanism is releasably attached to the mass.
To operate the battering ram to knock down an object such as a door, a portion of the compressed gas is released from the second portion of the housing into the charge cavity via the valve means. The battering ram is then swung at the door such that the first protruding end of the trigger mechanism hits the door causing the second end of the trigger mechanism to release the mass, thus allowing the mass to be propelled by the compressed gas through the object-striking end of the battering ram. Consequently, both the mass and the object-striking end of the battering ram housing strike the door together with a combined striking velocity which imparts a higher peak force for quickly and efficiently breaking down the door.
BRIEF DESCRIPTION OF THE DRAWINGS
Other objects and advantages of the invention will become apparent upon reading the following detailed description and upon reference to the drawings, in which:
FIG. 1 is a cross-sectional side view of a pneumatically-powered battering ram constructed according to the teachings of the present invention showing the battering ram in an armed position;
FIG. 2 is a schematic cross-sectional side view of a pneumatically-powered battering ram constructed according to the teachings of the present invention;
FIG. 3 is a back perspective view of a pneumatically-powered battering ram with a handle constructed according to the teachings of the present invention;
FIG. 4 is a perspective view of a pneumatically-powered battering ram with an alternative embodiment of the first end of the trigger mechanism constructed according to the teachings of the present invention; and
FIG. 5 is a perspective view of a pneumatically-powered battering ram constructed according to the teachings of the present invention being used by an individual to strike a door.
DETAILED DESCRIPTION OF THE INVENTION
Throughout the following detailed description, like reference numerals are used to refer to the same element of the invention shown in multiple figures thereof. Referring now to the drawings and, in particular to FIGS. 1 and 2, there is shown a pneumatically-powered battering ram 10 according to the present invention. The battering ram 10 includes a housing 12, a mass which is preferably a piston 14, a charge cavity 18, a supply of compressed gas 40 and a trigger mechanism 22. The housing 12 has a first object-striking end 24, a second opposed end 26, and an internal compartment 28. The internal compartment 28 includes a first portion 30 proximate the object-striking end 24 of the housing 12 and a second portion 32 proximate the second opposed end 26 of the housing 12. The piston 14 is disposed within the first portion 30 of the internal compartment 28 of the housing 12 proximate the object-striking end 24. The piston 14 includes a head 34, a connecting rod 36 and a base 38; the piston head 34 is disposed toward the object-striking end 24 of the housing 12.
The housing 12 may further include bulkheads 52, 54 and 56 disposed within the internal compartment 28. Bulkhead 52 is located proximate the object-striking end 24 of the battering ram 10 between the piston head 34 and the piston base 38. When the battering ram 10 is in an armed position ready to be fired, the piston head 34 is in close proximity to the bulkhead 52. Bulkhead 54 is located between the charge cavity 18 and the second end 26 of the housing 12. An aperture 88 extends through bulkhead 54 and operates in conjunction with the valve means 42 to fill the charge cavity 18 with compressed gas 40. Bulkhead 56 is located proximate the second opposed end 26 of the housing 12 and seals the second portion 32 of the internal compartment 28.
As shown in FIG. 1, a tank 20 may be disposed within the second portion 32 of the housing 12 to store the supply of compressed gas 40. Alternatively, the compressed gas 40 may be disposed directly into the second portion 32 of the housing 12 which is then sealed by bulkhead 56 to keep the gas 40 under pressure.
The battering ram 10 further includes a valve means 42 which operates to release a portion of the compressed gas 40 into the charge cavity 18. As best seen in FIG. 2, the preferred embodiment of the valve mechanism 42 includes an actuator rod 82 and a ball 84. The actuator rod 82 has a first end 85 affixed to the base 38 of the piston 14 and a second tapered end 86. The second tapered end 86 fits within an aperture 88 which extends through bulkhead 54, leaving sufficient room around the rod 82 for the gas 40 to enter the charge cavity 18 when desired. The ball 84 covers the aperture 88 in the bulkhead 54 and prevents the flow of gas until the charge cavity 18 needs to be refilled.
A trigger mechanism 22 is affixed to the object-striking end 24 of the battering ram housing 12. The trigger mechanism 22 has a first end 44 which protrudes past the object-striking end 24 of the housing 12 and a second end 46 which is releasably attached to the base 38 of the piston 14. The first end 44 of the trigger mechanism 22 may be either a collar 44a surrounding the perimeter of the object-striking end 24 of the housing 12 such as shown in FIG. 4 or a rod 44b protruding past the object-striking end 24 such as shown in FIGS. 1 and 5. The second end 46 of the trigger mechanism 22 preferably comprises a sear mechanism 48. The sear mechanism 48 is designed to abruptly release the piston 14 which is being held against the large restrained force of the compressed gas by the action of a much smaller force. The classic use of a sear mechanism is the trigger-firing pin mechanism of a gun. In a gunlock, the sear is a catch that holds the hammer of a gunlock at cock or half cock. When the trigger is activated, the sear releases the hammer, causing the gun to fire. Similarly, in the present invention, the sear mechanism 48 is a catch that holds the piston 14 of the battering ram 10 in an armed position until the trigger mechanism 22 is activated, causing the piston 14 to fire out of the object-striking end 24 of the battering ram 10. Vent 76 in the housing 12 allows the compressed gas 40 disposed in the charge cavity 18 to be vented after the sear mechanism 48 is released and the piston 14 is brought to the desired velocity.
To assist in the swinging of the battering ram 10, at least one handle 50 may be attached to the housing 12. In the preferred embodiment, best shown in FIGS. 3 and 5, the handles 50 surround the housing 12 such that when the battering ram 10 is not in use, it may be stored or transported without rolling.
In the preferred embodiment, the battering ram 10 further includes a reset mechanism 60 which uses compressed gas 40 from valve means 42 through feed pipe 72 to return or reset the piston 14 to an armed position. The reset mechanism 60 is preferably attached to the exterior of the housing 12 of the battering ram 10 proximate a handle 50. The reset mechanism 60 includes a reset valve cylinder 64 having an exhaust port 90 extending therethrough, a reset valve piston 66 with a piston feed port 68 and a piston vent port 70 extending therethrough, a feed pipe 72, a flow rate restrictor 74, and a reset knob 62. In embodiments of the battering ram 10 which include the reset mechanism 60, vents 78 and 80 are provided in the housing 12 to correspond and align with the piston feed port 68 and the piston vent port 70, respectively, of the reset mechanism 60. Optionally, anti-rotation guides 58 disposed at predetermined intervals along the exterior surface of the housing 12 may be provided to hold the trigger mechanism 22 and/or the feed pipe 72 in place and to prevent rotation.
As shown in FIG. 2, the battering ram 10 is in armed position and the piston vent port 70 is aligned with the vent 80 in the housing 12 and the exhaust port 90 in the valve cylinder 64. After the battering ram 10 has been fired, piston 14 must be returned to the armed position. The reset knob 62 is pressed, thus pushing the valve piston 66 within the valve cylinder 64 such that feed port 68 is aligned with vent 78 in the housing 12. The compressed gas 40 then travels through the feed pipe 72, the flow rate restrictor 74 and the aligned feed port 68 and vent 78 into the portion of the internal compartment 28 located between bulkhead 52 and the base 38 of the piston 14 to force the piston 14 to return to the armed position. The flow rate restrictor 74 functions to limit the gas flow and controls how hard the piston 14 will reset. Vent port 76 through housing 12, which was uncovered by the base 38 after firing, allows gas to escape from behind the base 38 during the return stroke. Upon return of the piston 14 to the armed position the sear mechanism 48 reengages the piston 14 and the charge cavity 18 is refilled by the action of the actuator rod 82 and the ball 84. The reset knob 62 is released by the user realigning the piston vent port 70 with the vent 80 in the housing 12 and the battering ram 10 is armed and ready.
Safety features may also optionally be incorporated into the battering ram 10. For example, over-pressure relief valves may be provided in the tank 20 and the charge cavity 18. A sear lock may also be provided to prevent the battering ram 10 from being fired when it is being stored. In addition, other optional features (not shown in the figures) include a pressure regulator of the type known in the art which accepts either liquid or gas which may be immersed in the compressed gas 40 or otherwise placed in the tank 20 or the sealed second portion 32 of the housing 12 to assure constant pressure in the charge cavity 18 and/or to allow the striking pressure of the compressed gas 40 released into in the charge cavity 18 to be adjusted to accommodate different striking situations.
To operate the battering ram 10 to knock down an object such as a door, a portion of the compressed gas 40 is released from the tank 20 (or the sealed second portion 32 of the housing 12) into the charge cavity 18 via the valve means 42. The piston 14 is restrained from movement against the pressure in the charge cavity 18 by the sear mechanism 48. The first end 44 of the trigger mechanism 22 protrudes from the object-striking end 24 of the battering ram 10 towards the door. The individual handling the ram 10 swings it toward the door in the conventional way. When the protruding end 44 of the trigger mechanism 22 reaches the door, the base 38 of the piston 14 is released by the sear mechanism 48. Upon release of piston 14 by the sear mechanism 48, the piston 14 is propelled at a high velocity through the object-striking end 24 of the housing 12 by the force of the compressed gas 40 contained in the charge cavity 18. Consequently, the object-striking end 24 of the housing 12 reaches the door together with the head 34 of the piston 14, with the piston 14 traveling at a much higher velocity than can be obtained by swinging alone. This high velocity brings the peak force on the door to a much higher level because the energy transfer to the door occurs in a shorter time. The total energy brought to bear on the door is also increased by the power assistance from the expanding compressed gas, preferably carbon dioxide. Thus, the battering ram 10 imparts a higher peak force and greater total energy for quickly and efficiently breaking down the door.
As with a conventional ram, the higher the weight of the battering ram 10, the better it will be at destroying doors, provided that the total weight does not exceed that which the individual handling the ram can carry and maneuver effectively. Thus, in an embodiment of the present invention intended to be operated by one individual, the battering ram 10 should weigh approximately sixty pounds in order to be maneuvered quickly and easily yet still effectively.
As the piston 14 is forced forward by the expanding gas in the charge cavity 18 there is an equal and opposite recoil force on the housing 12. In order for the individuals operating the battering ram 10 to be able to maintain control of the ram 10 during the swing, this recoil velocity must be kept within acceptable limits. In the preferred embodiment, the housing 12 weighs five to ten times as much as the piston 14 and the recoil velocity may therefore be as little as 1/10 the piston velocity. This recoil acts to slow the housing 12 as it is swung toward the door. A five ft/s (feet per second) ram swing velocity is considered attainable, so a final piston velocity of 55 ft/s (within the housing 12) would recoil the housing 12 to a complete stop at the moment of impact. However, the moving piston 14 will retain the velocity, and more importantly, the kinetic energy of the housing 12. The combined energies of the housing 12 and piston 14 are both applied to the door, thus the gas pressure assisted energy that can be applied to the door is approximately twelve times greater than that which can be applied by two individuals using a conventional ram.
As previously mentioned, although other types of compressed gas (such as air) may be used to fill tank 20, carbon dioxide gas is preferred. Carbon dioxide-filled tanks 20 typically contain liquid with a vapor pressure of about 850 psi at 70 degrees Fahrenheit which is an adequate pressure range for the task at hand. An eight ounce carbon dioxide tank 20, discharged into the charge cavity 18 at 500 psi, provides approximately fourteen charges before needing to be replaced or refilled.
While the invention has been described in conjunction with specific embodiments thereof, it is evident that many alternatives, modifications, and variations will be apparent to those skilled in the art in light of the foregoing description. Accordingly, the present invention is intended to embrace all such alternatives, modifications, and variations as falling within the spirit and broad scope of the claims. | A pneumatically-powered battering ram for striking objects quickly and effectively with an initial high striking velocity resulting in an increased peak force effective in breaking the target object. The battering ram includes an elongated hollow housing containing a mass to be propelled, preferably a piston, and a supply of compressed gas, preferably carbon dioxide disposed within the housing. A valve mechanism releases a portion of the compressed gas into a charge cavity located between the piston and the supply of compressed gas. A sear mechanism holds the piston in place against the pressure of the compressed gas in the charge cavity. When the battering ram is swung at an object such as a door, a trigger mechanism releases the sear mechanism which in turn releases the piston. The piston is then accelerated forward by the compressed gas charge. Consequently, as the ram reaches the door, so does the piston which is traveling at a much higher velocity than could be obtained solely by manual swinging. As a result, the peak force initially imparted upon the door is greater and the door is broken down in a quick and efficient manner. | 8 |
GOVERNMENT RIGHTS
This invention was made with U.S. Government support under Contract No. DABT 63-93-C-0025 awarded to Advanced Research Projects Agency (ARPA). The Government has certain rights in this invention.
FIELD OF THE INVENTION
This invention relates to electronic devices, and, more particularly, to providing accurate alignment of components of such device, and most particularly to field emission display ("FED") devices.
BACKGROUND OF THE INVENTION
As technology for producing small, portable electronic devices progresses, so does the need for electronic displays which are small, provide good resolution, and consume small amounts of power in order to provide extended battery operation. Past displays have been constructed based upon cathode ray tube ("CRT") or liquid crystal display ("LCD") technology. However, neither of these technologies is perfectly suited to the demands of current electronic devices.
CRT's have excellent display characteristics, such as color, brightness, contrast and resolution. However, they are also large, bulky and consume power at rates which are incompatible with extended battery operation of current portable computers.
LCD displays consume relatively little power and are small in size. However, by comparison with CRT technology they provide poor contrast, and only limited ranges of viewing angles are possible. Further, color versions of LCDs tend to consume power at a rate which is incompatible with extended battery operation.
At least partially as a result of the above described deficiencies of CRT and LCD technology, efforts are underway to develop new types of electronic displays for the latest electronic devices. One technology currently being developed is known as "field emission display technology." The basic construction of a typical field emission display, or ("FED"), is shown in FIG. 1. As seen in FIG. 1, field emission display 10 comprises an anode, generally designated 20, a cathode, generally designed 30, and a plurality of spacers 40 which prevent the anode 20 and cathode 30 from being pushed into contact with each other by exterior atmospheric pressure when the space between the anode and cathode is evacuated.
The anode 20 typically comprises a flat glass plate 101 with a transparent conductor layer 102 formed on its lower surface. The screen area of the anode (designated 104 in FIG. 2) includes a large number of phosphor dots 112 formed on the lower surface of transparent conductor 102.
Cathode 30 comprises a substrate or baseplate 114 on which thin conductive row electrodes 108 are formed. Silicon baseplate 114 may be single crystal silicon. The row electrodes may be formed from doped polycrystalline silicon that is deposited on the baseplate and serves as the emitter electrode, and are typically deposited in strips that are electrically connected. A resistive layer (not shown) may be deposited on top of the row electrodes 108 and spaced-apart cathode emitters 106 are in turn formed on top of the row electrodes 108. Also formed on the row electrodes 108 and baseplate 114 is a dielectric layer 116 on which, in turn, is a conductive layer 110 which forms a gate electrode and controls the emission of electrons 107 from emitters 106. Typically, millions of emitters 106 are required to provide a spatially uniform source of electrons.
FIG. 2 is a exploded diagram of an FED package, showing the anode 20 and cathode 30 of FIG. 1, together with additional components (e.g., a getter 35, a seal frit 40, backplate seal ring 45, frit layer 50, and backplate 55 with a compressible dot 60) that are typically included in the complete FED package. As is apparent from FIG. 2, it is important that the various components of the FED package, particularly the anode 20 and cathode 30, be positioned accurately relative to each other.
Conductors on a spacer ring 22 on anode 20 are bonded to conductive leads on the cathode 30, and the cathode and anode must be precisely positioned to each other at the time this bond is made. One method of connecting the conductive leads on the cathode 30 to the conductors on the spacer ring 22 of anode 20 is commonly known as flip chip bonding. In flip chip bonding, contact pads (not shown) on one substrate, e.g., on cathode 30, are provided with conductive "bumps" which are carefully aligned with the conductors on the spacer rail of another substrate (e.g., of anode 20). An apparatus commonly referred to as a flip chip bonder then bonds the contact pads of the cathode to the conductors of the anode using a process commonly referred to as thermo-compression bonding. Although the following discussion is directed to a procedure using a flip chip bonding machine or bonder used to bond the anode 20 and cathode 30 of an FED, it will be understood that procedures employing other types of bonders or the bonding of substrates of different devices are equally applicable.
Regardless of the particular bonder or procedure employed, the alignment between the cathode 30 and anode 20 is critical to obtaining a properly functioning FED. Accordingly, many flip chip bonders and the like are provided with some type of "machine vision" system which automatically aligns the cathode and anode prior to bonding.
However, machine vision alignment systems are not sufficiently accurate to ensure completely acceptable alignment. Therefore, after various portions of a device have been bonded together, the device is removed from the production line and taken to a test station at which a test procedure, commonly referred to as "veneering," is performed to evaluate the accuracy of the alignment.
FIG. 3 shows exemplary aligning marks 301, 305, (commonly referred to as "fiducials") on a pair of substrates 300 and 304 (which may be, for example, an anode assembly 20 and cathode assembly 30). In the prior art systems and in the practice of the present invention, aligning marks 301, 305 are used by a "machine vision" system to align the two substrates just prior to the two substrates being bonded together.
FIG. 3 also shows exemplary veneering marks 302, 306 on, respectively, substrates 300 and 304, for use in post-bonding inspection and evaluation. As will be apparent, aligning marks 301, 305 are provided adjacent two diagonally opposite corners of the substrates, while veneering marks 302, 306 are provided along pairs of adjacent edges.
Each aligning mark 305 on substrate 304 (e.g., on an anode assembly 20) is an open circle or "doughnut", typically having an inner diameter of about 100 microns and an outer diameter of about 200 microns. Each aligning mark 301 on substrate 300 (e.g., on a cathode assembly 30) is a solid round dot about 50 microns in diameter.
According to prior art practice, a "machine vision" system (e.g., a so-called "look-up, look-down" imaging system of the type used conventional flip bonders (those sold by Sierra Research and Technology, Inc. of Westford, Mass., Micro Robotics Systems, Inc. of Chelmsford, Mass. and RD Automation of Piscataway, N.J.) are used to automatically to align the two substrates to be bonded together so that each solid dot 301 on substrate 300 is centered within a respective round doughnut 305 on substrate 304. The machine vision system views the alignment marks on the two substrates and, either using pattern recognition software or by projecting images of the substrates on a video screen where they may be viewed by an operator, achieves alignment of the two substrates so that each solid dot 301 on substrate 300 is centered within a respective round doughnut 305 on substrate 300. This alignment is achieved with the two substrates in close proximity to each other, and the only additional movement required to bring them into contact for bonding is in the z-direction.
According to the prior practice, after the two substrates have been bonded together, the workpiece is removed from the production line and taken to a test station at which the veneering marks 302 and 306 are employed to evaluate the accuracy of the alignment of the substrates, e.g., of the anode assembly 20 and cathode assembly 30, under a microscope. Desirably, the two substrates will be aligned so that each veneering mark 302 on substrate 300 will be centered within a respective veneering mark 306 on the other substrate 304.
The configurations of veneering marks 302 and 306 are most clearly shown in FIGS. 4 and 5.
As shown in FIG. 4, each veneering mark 306 on substrate 304 comprises a row of identical boxes 401, equally spaced from each other. In the illustrated embodiment, each veneering mark 306 includes twenty aligned boxes 401.
Referring now to FIG. 5, each veneering mark 302 on substrate 300 includes a row of axially aligned bars 501. Each bar 501 is exactly the same length, a length equal to distance between a pair of adjacent boxes 401 so that each bar is capable of fitting precisely in the interval between a pair of adjacent boxes. The center-to-center spacing of bars 501, however, is slightly different than (in the illustrated embodiment 0.5 microns greater than) the center-to-center spacing of boxes 401; and the total number of bars 501 in each veneering mark 302 (in the illustrated embodiment twenty-one bars) is typically different (in the illustrated embodiment one greater than) from the number of boxes 401 in the corresponding veneering mark 306. A pair of arrows 502 are provided on the opposite sides of the center bar 501a, with the heads of the arrows pointing towards each other.
FIGS. 6, 6A and 7 illustrate the relative positioning of superposed veneering marks 302, 306 when the two substrates are (FIGS. 6 and 6A) or are not (FIG. 7) precisely and accurately aligned relative to each other. In each of FIGS. 6 and 7, the two arrows 502 of veneering mark 302 are positioned in the two center boxes 401a, 401b of mark 306.
In FIGS. 6 and 6A, in which the two substrates are aligned, the ends of the center bar 501a of mark 302 are tangent to the adjacent edges of boxes 401a and 401b. In FIG. 7, in which the two substrates are not perfectly aligned, center bar 501a is offset slightly, so that its left end is spaced slightly from the adjacent edge of box 401a and its right end projects slightly into box 401b. However, it will also be noted that the ends of another bar, i.e., bar 501g, appear to be tangent to the sides of the two boxes 401f and 401g between which the bar is positioned. Thus, the extent of the misalignment of the marks 302 and 306 in FIG. 7 can be accurately be determined simply by counting the number of boxes 401 between the bar 501a between the two center boxes 401a, 401b, and the apparently aligned bar 501g. In FIG. 7, there are six such boxes, and the extent of the misalignment is accordingly six (6) times the difference (0.5 microns) between the center to center spacings of the bars and boxes, or 3.0 microns.
It will thus be appreciated, that existing "veneering" procedures make it possible vary accurately to evaluate the extent of misalignment between two components that have been bonded together. Unfortunately, in order to evaluate alignment using such existing procedures, the device being evaluated must be taken out of the production line for evaluation, and then returned to the production line when the evaluation is complete. This results in production delays and additional product handling. There is a need for a system which evaluates and improves the quality of the alignment between the die and the substrate on-line.
SUMMARY OF THE INVENTION
The present invention provides a system and method that permits the accuracy of alignment of a transparent substrate relative to a second substrate to which it is bonded to be evaluated on-line, after the two substrates have been bonded together. According to a preferred embodiment, the alignment of the two substrates is viewed through the transparent substrate at an in-line inspection station to which the bonded-together substrates being transported from the station at which the bonding occurred, and preferably before the substrates are transported to a subsequent processing station.
In some preferred embodiments in which the two substrates are the anode (which is transparent) and cathode of an FED device, the system includes device carrier having an open bottom which supports the bonded-together cathode and anode assemblies, an alignment observer positioned below the carrier for observing the alignment marks on the assemblies and producing a signal representative of the observed alignment, and a display for receiving the signal and providing an image that permits the spatial relationship of the alignment marks to be determined.
DESCRIPTION OF THE DRAWINGS
For a more complete understanding of the invention and for further advantages thereof, reference is made to the following detailed description taken in conjunction with the accompanying drawings, in which:
FIG. 1 (previously discussed) is a plan view showing a typical field emission display.
FIG. 2 (previously discussed) is an exploded diagram showing the components of a typical field emission display used in both the prior art and in the practice of the present invention.
FIG. 3 (previously discussed) is a top view of substrates showing alignment and veneering marks useful both in prior art processes and in the practice of the present invention.
FIGS. 4 through 7 (previously discussed) are schematics showing the alignment and veneering marks of FIG. 3 in greater detail.
FIG. 8 is a schematic of an FED production system according to an embodiment of the invention.
FIG. 9 is a plan view of a device carrier used in the practice of the present invention.
FIGS. 10 and 11 are schematic diagrams of portions of the production system of FIG. 8.
FIG. 12 is a flow chart illustrating a further embodiment of the invention.
DETAILED DESCRIPTION
Reference is now made to FIG. 8 which schematically shows a portion of an FED production line in which a conveyor system generally designated 800 advances device carriers 810 (illustrated in more detail in FIG. 9, each of which supports a plurality (in the illustrated embodiment five) FED workpiece(s) as the workpieces advance through a number of successive workstations, designated 130, 140 and 150 respectively. In the illustrated system, the first workstation 130 (illustrated in more detail in FIG. 10) includes a flip chip bonder for bonding the cathode assembly 30 and anode assembly 20 of an FED together, the second workstation 140 (illustrated in more detail in FIG. 11) includes an alignment inspector for inspecting the alignment of the now bonded-together cathode assembly 30 and anode assembly 20, and the third workstation 150 includes a system (which itself is generally conventional in design and forms no part of the present invention) for assembling an acceptably aligned and bonded-together cathode assembly into a complete sealed FED package.
Referring now to FIG. 9, each device carrier 810 comprises a metal plate, the opposite longitudinal edges 812 of which are rolled downwardly to provide longitudinal stiffening and which also carries regularly spaced transverse stiffening ribs 814. Locator notches 816 are provided at the opposite ends of carrier 810, and locator holes are provided along the side edges of carrier 810, for positioning the carrier on conveyor 800. The conveyor 800 supports carriers 810 along their opposite longitudinal edges so that, as discussed hereinafter, the bottom of the carrier is unobstructed.
Carrier 800 also includes five FED workpiece locating portions, generally designated 818, that are precisely positioned relative to each other and are spaced longitudinally along the carrier 810. Each workpiece locating portion includes eight edge locators 817 projecting upwardly from the top of carrier 810, a central recess 820 generally between locators 817, and a pair of smaller recesses 822 at the opposite transverse sides of recess 820. In practice, edge locators 817 engage the edges of the anode assembly 20 of an FED being manufactured and hold it in position on carrier 810. The anode assembly 20 is designed so that the alignment marks 305 and veneering marks 306 on the it (and the alignment marks 306 and veneering marks 306 on the cathode assembly 30 after it is bonded to anode assembly) will be positioned within the bounds of recess 820.
As shown in FIG. 10, workstation 130 includes a flip chip bonder that is used to thermocompression bond a cathode 30 to an each of the anodes 20 carried by device carrier 810. One example of a bonder useful with the present invention is the MICRON-2, manufactured by Zevatech, Inc. Others include the an AFC-101-AP bonder manufactured by RD Automation, Inc., the MRSI-503M flip chip bonder manufactured by Micro Robotics Systems, Inc., and the model FC950 manufactured by ULTRA T Equipment Co. Other types of bonders, such as TAB bonders, may also be used.
As shown in FIG. 10, the machine vision system of the bonder in station 130 includes a pair of fixed CCD cameras 134 positioned below conveyor 800, rather than a conventional "look-up look-down" optical system. Otherwise, the bonder, including its machine vision system, are conventional. Conveyor 810 advances device carrier 810 in steps past the machine head 132 of the bonder and cameras 134. As each anode assembly 30 carried by device carrier 810 is advanced into position above cameras 134, machine head 132 picks up a cathode assembly 30 and moves it into place above the anode assembly 20. The CCD cameras 134 view the alignment marks carried on the cathode and anode assemblies, looking upwardly through the transparent anode assembly 20 from below conveyor 100. The machine vision system of the bonder processes the information supplied by each camera 134, and the positional information moves the machine head in the x, y and theta directions until the system determines that the alignment marks are properly aligned. The machine head then bonds the cathode 30 and anode 20 together.
After the cathode 30 and anode 20 have been bonded together, conveyor 800 advances carrier 810 to alignment inspection station 140 at which an inspection apparatus evaluates the alignment between the bonded-together cathode and anode. As shown, the inspection apparatus includes a video camera 162 mounted below conveyor 800 in position to look through recess 820 in carrier 810 and view the veneering marks on cathode 30 and anode 20 through the transparent glass plate 101 of anode 20.
In the embodiment shown in FIG. 11, video camera 162 sends a signal representative of the veneering marks on anode 20 and cathode 30 over signal cables 164, 166 to a video display 168 which presents an image of the superposed veneering marks, thereby allowing visual inspection of the alignment. To insure that the camera 162 has sufficient light to operate properly, a beam splitter (not shown) is used to shine light down the same optical path as the camera. Alternatively, a fiber-optic light source may be provided to illuminate the underside of anode 20. The camera 162 also may be provided, as shown, with optics 170 which provide magnification, for example 90×, of the veneering marks to allow for more precise observation. Either additionally (as shown) or alternatively, a computer 172 may provide electronically amplify or otherwise enhance the signal before it is displayed.
As indicated in FIG. 11, camera 162 is mounted in such a way that it can be moved in both the x and y directions. This permits each of the sets of veneering marks on the anode and cathode to be separately viewed, and for the particular set being viewed to be accurately centered in the camera's field of view.
Although the disclosed embodiment utilizes a video camera to observe the veneering marks on the anode and cathode, it will be evident that other alignment observers such as a CCD camera or the like may also be employed. Accordingly, as used in the claims, the term "alignment observer" means any device, system or apparatus that is capable of viewing the alignment marks on the anode and cathode or on similar superposed substrates.
In the embodiment of FIG. 11, the alignment of the anode and cathode is evaluated, and the acceptability of the alignment determined, by a human operator based on the image displayed on display 168. The extent of misalignment that is acceptable will depend on a number of things, including in particular the amount of misalignment indicated by the other sets of veneering marks 302, 306 on the bonded-together substrates being examined, and the percentage of devices being produced in which the degree of misalignment approaches the acceptable limit. It may, for example, be determined that the alignment of a bonded anode-cathode is acceptable if the maximum degree of misalignment indicated by any of the four sets of veneering marks on the bonded pieces does not exceed 2 microns.
If the alignment of the bonded cathode and anode is acceptable, conveyor 800 transports carrier 810 and the device to station 150 where the bonded anode and cathode are assembled into an FED package. If the alignment is not acceptable, the unsatisfactory device is removed from the productionline.
In many instances, an operator will determine the acceptability of alignment based in large measure on the operator's skill and experience. In other instances, the acceptability of the alignment may be determined with the aid of a computer, such as computer 172, as shown in the flow chart of FIG. 12.
With reference to the flow chart, after the bonded-together anode and cathode are placed at the inspection station (step 2000), conventional pattern recognition is used to locate the arrows 502 of one of the sets of veneering marks 302 on the cathode (step 2002). The location (x and y coordinates) and angular orientation are then calculated (step 2004) and used to permit pattern recognition to locate the boxes 501 of the associated superposed veneering mark 306 on the anode 20. (step 2006). The location of the center bar 501a of the mark 302 (step 2008) and most apparently aligned bar (e.g., bar 501g if the anode and cathode are aligned to the extent shown in FIG. 7) are then calculated, and this information is used to calculate the apparent degree of alignment (step 2010), and then evaluate the degree of alignment to determine if it is satisfactory (step 2012). If, in step 2012, the apparent misalignment of a pair of indicators is less than a predetermined extent of misalignment, e.g. 2 microns, the system determines that this particular alignment is satisfactory and proceeds to determine and evaluate the alignment of the next set of veneering marks 302, 306 on the bonded anode and cathode. If, on the other hand, step 2012 determines that the apparent misalignment is greater than 2 microns, the image of the indicators being evaluated is displayed on monitor 168 (step 2014) and the alignment is again evaluated, this time by a human operator (step 2016). If the human operator concludes that the alignment is satisfactory, the system proceeds to determine and evaluate the next set of indicators on the die. If the human operator evaluation determines that the alignment is not satisfactory, the particular device being evaluated is discarded, and the operator also determines the frequency at which the system is producing unsatisfactorily aligned devices (step 2018). If the frequency (e.g., percentage of rejects) is within some predetermined limit, the inspection procedure is permitted to continue; if it is not, the production line is shut down.
Although the invention has been described in connection with the bonding together of the anode and cathode of a FED, it will be apparent that the invention is also applicable to other electronic devices and structures in which the alignment of two superposed substrates, one of which is transparent, is viewed and evaluated.
More generally, it will also be recognized that the above described systems, apparatus, methods and procedures are exemplary of the invention, but are not limiting in that other systems, apparatus, methods and procedures will fall embody the invention and will fall within the scope of the appended claims. | A system and method that permits the accuracy of alignment of a transparent substrate relative to a second substrate to which it is bonded to be evaluated on-line, after the two substrates have been bonded together. The alignment of the two substrates is viewed through the transparent substrate as the bonded-together substrates are being transported between the station at which the bonding occurred and another processing station. | 8 |
BACKGROUND OF THE INVENTION
[0001] The present invention relates to metallic stud frames of a type used in the formation of a frame of a residential, commercial or industrial structure.
[0002] Historically, frames of such structures were formed of either wood, or concrete. In the case of load bearing structures, it is common to use a steel bar, known as rebar within a poured concrete structure. The use of vertical light gauge steel studs, in lieu of wooden studs to accomplish internal framing within a wood frame structure, is also well known in the art. It is, however, not known to employ thin gauge vertical studs in combination with exterior wall concrete framing in which the vertical stud elements operates to define an offset of distance between an exterior poured concrete wall and an interior plasterboard wall which is secured to one surface of such a vertical steel stud element.
[0003] A need for such a vertical steel stud frame element has arisen as a consequence of rapid on-site assembly techniques employing thin external concrete walls which have developed in the construction arts. The present invention therefore relates to such vertical metallic stud elements in which one rectilinear surface thereof may be poured as a part of a process of casting of an exterior concrete wall, its base and/or a load bearing resultant structure.
[0004] The need for such an improved metal stud frame element has long existed in the art.
SUMMARY OF THE INVENTION
[0005] A construction system includes a metallic stud definable in terms of an X, Y, Z coordinate system. The system comprises a Z-axis elongate substantially rectangular integral web within a YZ plane thereof, said web having stability means along a Z axis line of dependency with a first edge of said web, said means defining an L-shaped element having a foot occupying a YZ plane substantially parallel to said web. The system also includes a second and opposite Z-axis edge of said web defining a series of substantially trapezoidal cut-outs therein having an opening thereto at a minor base of each trapezoidal cut-out.
[0006] The stud is preferably formed of a thin gauge steel.
[0007] It is accordingly an object of the present invention to provide a metallic stud framing element particularly adapted for use within a concrete framing structure.
[0008] It is another object to provide a metallic stud of the above type which can function as an interior to exterior wall-defining offset.
[0009] It is a further object of the invention to provide a vertical metallic stud capable of defining the shape and extent of vertical load bearing concrete columns within a poured concrete structure.
[0010] The above and yet other objects and advantages of the present invention will become apparent from the hereinafter set forth Brief Description of the Drawings, Detailed Description of the Invention and Claims appended herewith
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] FIG. 1 is a perspective view of a first embodiment of an inventive metallic stud.
[0012] FIG. 2 is a transverse cross-sectional view taken through Line 2 - 2 of FIG. 1 .
[0013] FIG. 2A is a transverse cross-sectional view taken through Line 2 A- 2 A of FIG. 1 .
[0014] FIG. 3 is an exploded view showing the stud frame of FIG. 1 in combination with upper and lower system framing elements.
[0015] FIG. 4 is a view, further to the view of FIG. 3 , in which a concrete upper and lower base of a resultant structure is formed.
[0016] FIG. 5 is an assembly view of FIG. 4 .
[0017] FIG. 6 is a vertical YZ plane sectional view of a resultant structure showing the inventive stud wholly embedded within a poured concrete exterior wall.
[0018] FIG. 7 is a view, further to the view of FIG. 5 , including a concrete capstan and base in the XY plane of a resultant structure.
[0019] FIG. 8 is a perspective view of a second embodiment of the invention.
[0020] FIGS. 9 and 9A are transverse cross-sectional views of the structure of FIG. 8 .
[0021] FIG. 10 is a view of the second embodiment otherwise similar to that of FIG. 3 .
[0022] FIG. 11 is a view further to FIG. 10 and similar to that of FIG. 4 .
[0023] FIG. 12 is a view of the embodiment to FIGS. 8-11 including a concrete capstan and base.
DETAILED DESCRIPTION OF THE INVENTION
[0024] With reference to the perspective view of FIG. 1 , the present inventive metal stud element for use in framing systems, as set forth above, may be seen to be definable in an X, Y, Z coordinate system as shown in FIG. 1 .
[0025] More particularly, an inventive stud element 10 includes an integral web 12 having a Z-axis elongate structure within a YZ plane, which structure is substantially rectangular. The web 12 includes an elongate stabilizing means 22 / 24 which depends upwardly in the X-axis direction and then bends back in the YZ direction of the web as is reflected in element 26 . See also FIGS. 2 and 2A .
[0026] Upon opposite edge 20 of web 12 is shown a plurality of interdigitated trapezoids which, more particularly, include individual trapezoidal or tabs cut-outs 11 separated by complemental non-cut-out trapezoids 20 . The mouth of each trapezoid is indicated by reference numeral 15 , while the major base thereof is represented by reference numeral 18 . The slanted sides 13 connect mouth 15 to major base 18 of each trapezoidal cut-out. As may be noted, the trapezoidal cut-outs 11 exhibit a unique geometry at their mouths 15 which, more particularly, is defined by hook-like structures 17 which point inwardly in the direction of major base 18 and stabilizing means 22 / 24 .
[0027] The structure of FIG. 1 is shown in further detail in FIGS. 2 and 2A which are cross-sectional views taken, respectively, through Lines 2 - 2 and 2 A- 2 A. Therein it may be appreciated that the transverse width of web 12 is less at the cross-section 2 A- 2 A than at cross-section 2 - 2 . In all other respects, the web 12 and L-shaped element 24 / 26 constitute stabilizing means of each metallic stud frame element. As may be appreciated in my U.S. Pat. No. 6,988,347, the cross-sectional geometries of FIGS. 2 and 2A may, in a given application, be expressed with considerable additional complexity.
[0028] In FIG. 3 is shown a plurality of the above metal stud frame elements 10 oriented in a vertical position and in exploded view relative to top and bottom securement beams 28 and 30 respectively.
[0029] FIG. 4 is a view, substantially similar to that of FIG. 3 in which, however, the bottom portion of each metal stud frame element 10 has been embedded within a concrete capstan.
[0030] FIG. 5 is a view, generally similar to that of FIG. 4 in which, however, each upper portion of each metal stud frame element is embedded within each upper capstan 31 while the bottom region of each metal stud frame is embedded within a lower capstan or footing 32 . Shown at reference numeral 35 of FIG. 5 is one geometry which rebars may take in the upper capstan 31 of the system.
[0031] A further rebar is shown as reference numeral 37 in footing 32 .
[0032] FIG. 6 shows the manner in which non-cut-out portions or tabs 20 , interdigitating between trapezoidal geometries 11 , may be fully embedded within a thin concrete wall 34 which forms an exterior of the structure to be framed. Therefrom the utility of the present metal stud frame may be appreciated with respect to both thin concrete and plasterboard construction. FIG. 6 further shows an elongate U-shaped double rebar 33 which may be used to hang a wall consisting of a plaster board vertical section 36 and a concrete upper capstan 29 .
[0033] The structures of FIGS. 5 and 6 may be seen in horizontal cross-sectional view in FIG. 7 , in which the trapezoidal cut-outs 11 of the metal stud frame element 10 may be seen embedded within concrete wall 34 and plywood layer 41 may be seen optionally placed upon plaster board 36 , or in lieu thereof.
[0034] As may be seen, web 12 spans the entire cross-sectional distance between the cut-out edge 20 of the metal stud frame and the stabilizing or L-shaped surface 24 / 26 thereof. Therefrom, it may be appreciated that pre-formed walls may be effectively constructed in accordance with the present method and that the rebar assembly 33 (see FIGS. 6 and 7 ) may be employed to essentially hang the stud frame system from the upper capstan 29 of the system. Therein, in FIG. 6 may be further noted that the stud element are countersunk into the upper capstan and lower footing as is indicated by dotted lines 35 and 40 respectively.
[0035] With reference to FIGS. 8 through 11 , there is shown a second embodiment of the present invention which, generally, corresponds to the above-described structures of FIGS. 1-4 of the first embodiment of the invention. More particularly, in FIG. 8 it may be seen that the second embodiment thereof differs from FIG. 1 only its elimination of L-shaped or stabilizing edge 24 and, in lieu thereof provides an elongate XZ plane surface 124 upon which respective webs 112 and 126 are folded downwardly within a frusto-conical cross-section which is essentially symmetric about a YZ longitudinal plane of the embodiment of FIG. 8 . The structure of FIG. 8 follows, in salient part, that of the metal web 12 of FIG. 1 including, trapezoidal cut-outs 111 / 111 A at edge 120 / 120 A. In each web 112 / 126 is provided bases 118 / 118 A of each trapezoidal cut-out, interdigitating uncut portions 121 / 121 A, and sidewalls 113 which connects mouths 115 of each cut-out to the bases 118 thereof. The embodiment of FIG. 8 , as in the embodiment of FIG. 2 , also displays hooks or angulated edges 117 of each mouth 115 , the purpose of which is to ensure securement of the plurality of trapezoidal cut-outs within the cement slabs 30 within which uncut portions 121 are secured. See FIG. 11 .
[0036] FIGS. 9 and 9A are cross-sectional views take through Lines 9 - 9 and 9 A- 9 A of FIG. 8 . Therefrom, the greater length of material in the cross-sections metal frame stud element which exists between the trapezoidal cut-outs may be appreciated. As may be further noted, each edge of each metal stud web of the embodiment of FIGS. 8 and 9 may have different lengths as may be noted from the distance of surface 124 to edges 118 / 118 A versus edges 120 / 120 A.
[0037] FIG. 10 is a view, generally similar to that of FIG. 3 , showing that the second embodiment of the stud frame element may be used in a substantially identical fashion to that of the simpler geometry of embodiment 1.
[0038] In FIG. 11 is a view substantially similar to that of FIG. 4 , from which, however, may be appreciated the enhanced truss-like strength of the second embodiment of the invention from which, as a practical matter, given a sufficient gauge of the metal truss frame elements, structures resultant from the assembly of FIG. 11 are virtually impossible to bend under any known wind and storm conditions. The embodiment as shown in FIG. 11 may be equipped in the fashion of FIGS. 6 and 7 with concrete outer surfaces to render yet more stable and wind resistant the entirety of the structure.
[0039] FIG. 12 is a view of the embodiment of FIGS. 8-11 including a concrete capstan 30 as the base of the structure.
[0040] While there has been shown and described above the preferred embodiment of the instant invention it is to be appreciated that the invention may be embodied otherwise than is herein specifically shown and described and that, within said embodiment, certain changes may be made in the form and arrangement of the parts without departing from the underlying ideas or principles of this invention as set forth in the Claims appended herewith. | A construction system includes a metallic stud definable in terms of an X, Y, Z coordinate system. The system includes a Z-axis elongate substantially rectangular integral web within a YZ plane, the web having a stability elements along a Z axis line of dependency with a first edge of the web, the elements defining an L-shaped element having a foot occupying a YZ plane substantially parallel to the web. The system also includes a second and opposite Z-axis edge of the web defining a series of trapezoidal hook-like structures having openings at a minor base of each trapezoidal hook-like structure. | 4 |
FIELD OF THE INVENTION
The invention relates to a method for adjusting the boundary surface or the location of the dispersion zone in the vertical direction in liquid—liquid extraction, in between two solutions that are mutually separable owing to gravity, and to a method for conducting the separated solutions out of the space where the separation takes place, advantageously so that an aeration of the solutions in the transfer step is prevented. The invention also relates to an apparatus for realizing the method.
BACKGROUND OF THE INVENTION
In large extraction plants, such as copper extraction, the adjusting of the solution boundary surfaces and the discharging of the solutions are combined by adopting two collecting chutes provided with solution overflows, which chutes extend vertically over the whole final end of the separation part. Generally there are used two attached chutes, the first of which—in the solution flow direction—is a fixed chute collecting the lighter organic solution as overflow, and the latter is a chute collecting the aqueous solution, provided with an adjustable overflow edge. The heavier solution, i.e. the aqueous solution, is conducted from underneath both chutes through a duct formed in between the chute bottoms and the separation part bottom. From this duct, the aqueous solution turns up and flows in the form of a U-turn in the collecting chute, in a direction that is opposite to the original flowing direction.
The adjustable overflow of the aqueous solution is formed of an outer edge of an aqueous solution chute, known in the prior art, which is constructed of a wall plate extending up to a given height and of another plate moving against it. This structure, provided with a horizontal overflow edge, serves as the basic overflow level, arranged at a height which it is unnecessary to go below from the adjusting point of view. The adjusting range proper locates above this level, and it is taken care of by means of a movable plate part, the overflow edge of which is likewise maintained in horizontal position.
The above described aqueous solution chutes provided with overflow edges include some drawbacks. Two plates moving against each other cannot be made compact, but a remarkable part of the overflow, about 10-40% thereof, passes along some other route than over the overflow edge. Therefore the adjusting of the phase boundary surface works properly only when the solution feeds surpass about half of the amount for which the extraction plants are designed. Moreover, when driving down the process, the above described overflow causes a solution flow to the next process step and thus weakens the extraction results in connection with the next drive up. There is also the danger that the boundary surfaces of the separation parts fluctuate, in which case a phase dispersion carrying impurities and located in between pure phases is transported along with the separated solutions.
SUMMARY OF THE INVENTION
By means of the method and apparatus of the present invention, we have now attempted to avoid the above described drawbacks, and the object is to improve the accuracy in the adjusting of the boundary surface in between the solutions, and at the same time prevent an aeration of the solutions and thus to improve the controllability of the flow of the separating solutions. A good adjustability is particularly important with liquid—liquid extraction, when driving the process up an down. According to the invention, the boundary surface between the solutions is adjusted by adjusting the overflow surface, so that in the bottom part of the aqueous solution end, there are installed several vertically adjustable tubular members, whereto the aqueous solution flows from the downwardly direction and is discharged to the surrounding aqueous solution chute through the top element of the tubular member. The aeration of separated solutions is prevented by means of a structure where the settled solution flows from the solution end via a shaft-like weir box positioned lower than the bottom of the solution end to the tubular lines. The prevention of aeration is important particularly for the extraction solution. Said weir box can also be provided with additional structures for avoiding the creation of vortexes and the absorption of air into the solution through them. The essential novel features of the invention are apparent from the appended patent claims.
BRIEF DESCRIPTION OF THE DRAWING
The invention is described in more detail with reference to the appended drawings, where
FIG. 1 is a schematical illustration of the cross-section of the separation part, i.e. of the settler, in the longitudinal direction,
FIG. 2 illustrates the structure used for discharging the aqueous solution,
FIG. 3 is a top-view illustration of the discharge end of the settler,
FIG. 4 shows the structure of the discharge end of the settler in cross-section,
FIG. 5 a illustrates the structure used for discharging the extraction solution in cross-section, and
FIG. 5 b is a side-view illustration of the same structure,
FIG. 6 a is a schematical side-view illustration of a preferred embodiment of the same structure, and
FIG. 6 b is a top-view illustration of the same structure,
FIG. 7 a illustrates the liquid seal used in the discharge of the extraction solution in cross-section, and
FIG. 7 b is a top-view illustration of the object of FIG. 7 a.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 is a schematical illustration of the structure of the separation part, i.e. of the settler 1 . A dispersion 2 of two different phases mixed in the mixing unit, i.e. the mixer (not illustrated in the drawing) flows into the settler which at its front end is provided with picket fences 3 , 4 and 5 . When flowing forward, the dispersion is gradually divided into two separate layers, an upper organic phase layer 6 and a lower aqueous solution layer 7 . In between the phases, there remains a continuously thinning dispersion layer. Part of the aqueous solution can be removed into circulation from the settler after the last picket fence 5 through the collecting channel 8 . The organic phase is removed from the settler as overflow to the chute 9 of the lighter phase, the front end of said chute being fixed, but advantageously rounded according to the drawing. The aqueous solution continues proceeding from underneath the organic phase chute to the water end 10 of the aqueous solution phase. The aqueous solution rises to the water end first through tubular members 11 and from inside them as overflow to the water end 10 proper.
The advantageous discharge method of the aqueous solution according to the invention is described in more detail in FIG. 2 . The aqueous solution flows through a duct 14 formed by the lower bottom 12 of the water end 10 and the settler bottom 13 to the lower tubular element 15 of the tubular member 11 , which element 15 is telescopically connected to an upper tubular element 16 . Advantageously the top edge 17 of the top element is constructed to be upwards expanding, so that the overflow speed can be reduced by means of this structure and the adjusting made even more accurate.
In order to connect the telescopically joined tubes 15 and 16 in a compact fashion, the structure can be further secured by attaching on the tube surfaces a bellow-like element 18 connecting the tubes to each other. The height of the bellow-like element is such that it enables the rising and lowering of the tubes in relation to each other throughout the length of the adjusting range. The lower element 15 of the overflow pipe 11 is compactly attached to the lower bottom 12 . The lower bottom itself is advantageously located at the same height as the bottom of the organic solution discharge chute 9 . By employing the method illustrated in the drawing, it is thus possible to adjust the height of the aqueous solution surface in an accurate and controlled manner without uncontrolled solution flows over the adjusting edge, and at the same time there is adjusted the height of the boundary surface between the solutions.
FIG. 3 is a top-view illustration of the phase discharge end, in which case there is located, first in the flow direction, the organic phase discharge chute 9 and thereafter the water end 10 of the aqueous solution. In the drawing it is seen that the overflow height of the tubular members 11 can be adjusted in groups of several pieces by means of an adjusting bar 19 . In the drawing, to the adjusting bar 19 there are connected three overflow pipes 11 , but the number can naturally vary. In FIG. 4 the same phase discharge end is shown in cross-section. In between the overflow pipes, there are seen supporting structures of the discharge end.
In the discharge end of the settler, there is thus formed, according to the present invention, a uniform aqueous solution space 10 , restricted, when seen in the flowing direction of the solutions, at the front end by the organic phase overflow chute 9 , and at the final end by the rear end of the settler 1 and at the sides by the side walls of the settler. As is apparent for instance from FIG. 3, the overflow pipes 11 are located side by side in the water end 10 . The number of the overflow pipes is adjusted to be such that the flow speed in the overflow pipes is set within the range 0.3-0.7 m/s.
Large copper extraction plants include process steps where the external feed of the aqueous solution into the step, and respectively the discharge of aqueous solution from the step, is remarkably smaller than the quantity of extraction solution flowing from one step to the next. Because the solution contact performed in the mixer between the organic and aqueous solution takes place roughly in a ratio 1:1, and still the aqueous solution feed from outside the step into the mixer is slight, the major part of the aqueous solution must be fed in through the settler part of the same step. In connection with FIG. 1, there was mentioned the collecting channel 8 , through which the major part of the aqueous solution can advantageously be absorbed into circulation, and thus the aqueous solution needed in this recirculation does not charge the discharge end 10 of the aqueous solution. In that case the water end 10 is needed only for circulating the aqueous solution going to external recirculation. For instance in the extraction solution washing step the external supply of aqueous solution is of the order 50 m 3 /h, although the aqueous solution supply into the mixer is of the order 1,000-2,000 m 3 /h. In that case it is clear that the number of overflow pipes 11 required in the water end 10 is fairly small. It is likewise possible in corresponding cases to reduce the transversal area of the overflow chute without making the water end narrower.
The removal of the separated solutions from the extraction solution chute and from the water end, and the conducting of the solutions to the next process step, is according to the invention arranged so that the solutions and particularly the extraction solution 6 are transferred to the next step by avoiding the aeration of the solution. In FIGS. 3 and 4 it is seen how the extraction solution chute 9 continues in the sideways direction in a way to outside the settler proper, and through this outer weir box 20 of said chute the solution is conducted to the next process point. According to FIGS. 5 a and 5 b , the weir box 20 of the extraction solution chute is in a shaft-like fashion deeper than the chute 9 itself, and an extraction solution transfer pipe 21 is connected thereto, at the bottom part of the weir box. Instead of one, the number of transfer pipes can be for instance two, in which case the construction of oversized circulation pipes is avoided. The two-pipe structure has the advantage that there are avoided situations where for example the bottom part of one large pipe of organic solution is filled with aqueous solution that can plug the proceeding of the extraction solution. The weir box of the extraction solution chute is advantageously located at either side of the settler, but the corresponding shaft-like weir box of the aqueous solution can be placed freely at the rear wall of the water end, or on either side of the side end of the water end 10 .
As was mentioned above, the removal structure 20 of the aqueous solution can be located at different spots in the chute. The location depends on which step is in question and where the aqueous solution is conducted next. It is naturally sensible to place the removal point in a location where the number of transfer pipes to the next step is as small as possible. A shaft-like structure enables a horizontal outlet of the pipework connected to the structure on a level as high as possible, in which case pumping becomes easier and deep pipework excavations can be avoided. A remarkable advantage is already the fact that the pipes can be drawn on ground surface.
The shaft-like weir box 20 prevents air from entering the solution. In order to prevent air from entering, the structure can be further improved by providing the ceiling part of the weir box with downwardly oriented and essentially vertical plates 22 in front of each pipe outlet 21 . It is in fact advantageous to install the plates so low that the extraction solution chute is nearly full, in which case the chute does not absorb air. Another additional preventive method for the absorption of air is a lattice channel 24 located in the vicinity of the liquid surface and illustrated in FIGS. 6 . This obstacle is useful when driving with an incompletely filled extraction solution chute or water end and works in a circulation-attenuating fashion also in normal runs, which do not officially need said obstacles. The lattice channel 24 is arranged so that its top end extends to above the liquid surface, but it can also be located underneath the liquid surface, even as much as for the length of the lattice channel.
The use of the removal structure 20 prevents air from being absorbed into the solutions to be discharged. The structure is shaft-like, and the bottom 23 of the structure is located lower than the bottom of the solution chute, so that the height difference is 0.3-1.0 times the chute width.
In large extraction plants, the extraction solution storage tank is generally located in a separate storage tank area, which is placed so low that the solutions are made to flow there by applying free release. This is often carried out with a drop of several meters, and leads to an intensive aeration of the solution. From FIGS. 7 a and 7 b it is seen how aeration can be prevented, particularly in pipeworks to be conducted into storage tanks by using a liquid seal, which is installed in the extraction chute 9 , prior to the removal structure 20 . The question is of an elongate overflow 25 , which in a way forms a chute in the discharge chute, in the middle of the outlet end. Loosely around the overflow there is constructed a vertical plate 26 extending remarkably lower than the liquid surface. Advantageously these arise as far as the edge of the extraction solution chute, and from there starts a cover 27 , illustrated in FIG. 7 b , which continues towards the solution discharge direction and extends in a uniform shape over the discharge shaft 20 , too. The pressure of the air space left underneath the cover is equalized by means of a vertical pipe 28 leading to this space.
The above described overflow to be conducted to the storage tank can be horizontal or evenly descending towards the incoming direction, while the lowest part is formed of the section crossing the extraction solution chute, and the topmost part of the overflow sections bordering the discharge shaft. From the point of view of flow technology, the latter solution is more recommendable, because it reduces the drop height of the overflow and thus limits the mixing of air into the extraction solution. However, the danger of mixing is clearly smaller when using a liquid seal described above.
In the above specification we have described the method and apparatus according to the invention mainly with reference to copper extraction, where large extraction plants are used, and attempted to find solutions to their problems. It is, however, clear that the method and apparatus can be applied to other extraction plants, too. | The invention relates to a method for adjusting the boundary surface between the two mutually separable solutions in liquid—liquid extraction at the discharge end of the separation part and for preventing the aeration of the solutions when discharging them from the separation part, so that the overflow height of the settled, lighter organic solution is maintained constant. In order to adjust the boundary surface in between the mutually separable solutions, the overflow height of the heavier aqueous solution is adjusted by conducting the settled aqueous solution from down upwards through tubular elements, in which case the height of these overflow pipes can be adjusted. The aeration of the solutions when discharging them from the separation part is prevented by conducting the solutions into transfer pipes through covered, shaft-like weir boxes that are deeper than the discharge end. The invention also relates to an apparatus whereby the boundary surface between the solutions is adjusted and the aeration prevented. | 1 |
FIELD AND BACKGROUND OF THE INVENTION
The present invention relates in general to sewing machines and in particular to a new and useful controlling mechanism for the step motor of a sewing machine which utilizes stored digital information to produce different stitch patterns.
Electronically controlled sewing machines preferably have step motor drives to control the alteration of the lateral swing-out motion of the needle bar and the feeding motion of the cloth feeder because such drives are excellently suited for the conversion of the digitally stored stitch information. The transmission ratio between the step size of the step motor and the respectively driven element must be selected so that, at a fine enough gradation of the adjusting motion, the adjustment of the driven element within the maximum adjustment range can be made fast enough within the time available. However, under certain conditions the existing gradation from step to step is insufficient. A further division is then necessary.
In one known sewing machine (U.S. Pat. No. 4,191,120), the step setting of the step motor to alter the transport motion of the sewing machine can be corrected manually. This is done by energizing the two phase windings of the step motor differently by means of two potentiometers. Due to this measure, the adjustment of the cloth feed control element can be divided further within the minimum feed range. Due to the better fine adjustment of the control element, better sewing results can be obtained, especially when feeding steps near the zero transport range are made for both forward and backward sewing. The differences resulting in this range between forward and backward feeding, depend upon the type of material to be sewn and upon the operating mode of the cloth feeder so that adjustability must be provided if the quality of the sewing work to be performed is not to suffer. This difference also depends on the exact factory-set step setting of the step motion of the zero transport position of the control element.
Such a correction is especially necessary when sewing patterns are involved which contain a multiplicity of stitches to be made in the one as well as in the other transport direction. In such cases, every feeding difference between the two transport directions, not recognizable in individual stitches, shows as cumulative error which can make the sewing result useless.
The above mentioned known sewing machine solves the problem only very imperfectly because the fine adjustment is restricted only to the minimum feed range of the sewing machine. When set to longer stitch lengths, a correction for the exact execution of forward and backward stitches of the same size is not possible.
SUMMARY OF THE INVENTION
It is an object of the present invention to make the step setting correction possible over the entire step range of the step motor and to combine it with the step motor control. Accordingly an object of the present invention is to provide a sewing machine which has a main shaft, a vertically guided needle bar in driving connection with the main shaft for a lifting motion of the needle bar, a step motor with a plurality of phase windings that can be controlled by a microcomputer connected to setting means for the control of the size and direction of the feeding action of the cloth feeder, and a pulse generator connected to the main shaft and triggering the step motor motion, wherein the microcomputer is connected to a digital-to-analog converter over a buffer memory, and to the non-inverting input of a comparator which controls the turning on and the turning off as well as the intensity of a phase current for each phase winding of the step motor and whose inverting input is connected to a discriminating element disposed in a phase circuit of the step motor for controlling the step motor.
According to the invention, a step motor control for a sewing machine is provided which not only permits the execution of a correction by finely graduated stages of the step position that is preset by the step motor in a simple maner, but in addition also makes possible an intensification of the driving torque of the step motor and of the holding moment in certain holding positions of the step motor. Moreover, a different correction in different situations can be preset in a simple manner through a microcomputer.
A special adaptation for the correction to the parameters of the step motor design results from the use of an D/A converter.
A further object of the invention is to provide a sewing machine with a circuit for controlling a step motor which controls the movement of either the needle bar, the cloth feeder or both, which is simple in design, rugged in construction and economical to manufacture.
The various features of novelty which characterize the invention are pointed out with particularity in the claims annexed to and forming a part of this disclosure. For a better understanding of the invention, its operating advantages and specific objects attained by its uses, reference is made to the accompanying drawings and descriptive matter in which a preferred embodiment of the invention is illustrated.
BRIEF DESCRIPTION OF THE DRAWINGS
One embodiment of the invention is depicted in the drawings wherein:
FIG. 1 is a view of the moving parts of a sewing machine, especially for the stitch length adjustment by means of a step motor;
FIG. 2 is a block circuit diagram showing the step motor control;
FIG. 3 is a simplified circuit diagram of the power control and of the output stage of a step motor phase circuit;
FIG. 4 shows control and level voltage curves and the phase current curve of a step motor phase winding correlated as to time;
FIG. 5 shows phase current curves of both step motor phase windings when executing full and half steps while being driven as well as in a full and a half-step holding position correlated as to time; and
FIG. 6 shows phase current curves of both step motor phase windings in successive correction positions correlated as to time.
DESCRIPTION OF THE PREFERRED EMBODIMENT
As FIG. 1 shows, the sewing machine is equipped with a main shaft 1 which, via a crank 2 and a link 3, causes a needle bar 6 equipped with a needle 4 and mounted in a guide rocker 5 to perform vertical strokes. The guide rocker 5 is mounted by means of a trunnion 7 in the sewing machine housing (not shown).
The guide rocker 5 has a lug 8 which is connected via a link 9 to a crank 10 fastened to the shaft 11 of a step motor 12 disposed in the sewing machine housing for the control of the overstitch width of needle 4.
Via a chain (not shown), the main shaft 1 drives a lower shaft 13. Fastened to the shaft 13 is a gear 14 which meshes with a gear 15 fastened to a shaft 16 mounted parallel to shaft 13. Screwed to shaft 16 is a lifting eccentric 17 with a cam 18. Also fastened to shaft 16 is an eccentric 19, around which grips an eccentric bar 20 to which are linked by means of a bolt 21 two links 22 and 23. The link 22 is rotatably connected by a bolt 24 to an angular lever 25 which is rotatably mounted to a shaft 26 fastened in the sewing machine housing and connected via an arm 27 of the angular lever 25 and a rod 28 to a crank 29 fastened to a second step motor 31 disposed in the sewing machine housing and effecting the control of the sewing machine stitch length.
By means of a bolt 32 the link 23 is linked to an arm 33 of a rocking lever 34 mounted to the shaft 13. A second, upwardly projecting arm 35 of the rocking lever 34 has at its end a guide slot 36 in which a pin 37 is guided. The pin 37 is fastened to a carrying arm 38 movably mounted to a horizontal shaft 39 fastened in the sewing machine housing parallel to the feeding device. At its free end the carrying arm 38 supports a cloth feeder 40 provided for the transport of material to be sewn by the needle 4 in collaboration with a looper (not shown). The carrying arm 38 is supported by the cam 18 of the lifting eccentric 17 via a leg 41 pointing downwardly.
In their design and in their basic control the two step motors 12 and 31 are identical. Consequently, to understand their operating mode it suffices to describe the control of step motor 31.
The step motor 31, serving for the control of the sewing machine stitch length, is designed as a two-phase step motor. It is controlled by a microcomputer 42 (FIG. 2) in whose memory is stored in known manner a multiplicity of various sewing patterns.
Connected to the microcomputer 42 is a pulse generator 43 controlled by the sewing machine main shaft 1 and transmitting a pulse with every revolution of the main shaft 1 whenever the cloth feeder 40 is not in engagement with the sewing material and the step motor 31 can perform a stitch setting change. For pulse shaping the pulse is fed to a comparator 44 whose output is connected to the INT input of the microcomputer 42.
Via a group of eight data lines 47 the microcomputer 42 is connected to a buffer memory 48 for the transmission of the control processes for the two phase windings 49 and 49' present in the step motor 31 and operated with a constant current chopper control. In addition, the output P11 of the microcomputer 42 is connected to the buffer 48 through a line 50 while the output WR of the microcomputer 42 is connected to the buffer 48 through the line 51.
Since the control circuits between the buffer 48 and the phase windings 49, 49' are of identical design, only the control for the phase winding 49 will be described. Identical elements in both control circuits have been given the same reference symbols but with primes.
The buffer 48 is succeeded by a digital-to-analog converter unit 52 in which a control voltage U ST is generated. It is fed through a line 53 to a chopper stage 54 where it is compared with an actual voltage U I furnished through a line 55 by a step motor output stage 56. The two phase windings 49, 49' of the step motor 31 are connected to the step motor output stage 56. Also, the microcomputer 42 and the output stage 56 are interconnected by lines 58 and 59 for the transmission of switching voltages U 0 and U 1 .
The buffer 48 serves the output extension of the microcomputer 42 in order to divide the half-steps normally executed by the step motor 31 once more into seven intermediate steps for balance correction.
The buffer 48 (FIG. 3) has outputs 0,1,2 directly connected to inputs 0,1,2 of a D/A(digital-to-analog) converter 60 while an additional output 3 of the buffer 48 is connected via a resistor 61 to an input 3 of the D/A converter 60. The input 3 of the D/A converter 60 is grounded via a resistor 62. The output of the D/A converter 60 is connected to the non-inverting input of an impedance converter 63 and to ground via a capacitor 64.
The output of the impedance converter 63 is connected through line 53 to a voltage divider 65 consisting of resistors 66 and 67, the latter being grounded. A capacitor 68 is paralleled to the resistor 67.
The junction between the resistors 66 and 67 is connected via a resistor 69 to the reference input of a comparator 70 to whose inverting input the line 55 is connected via a resistor 71. The inverting input of the comparator 70 is grounded via a capacitor 72.
The output of the comparator 70 is connected via a capacitor 73 to the non-inverting input of a second comparator 74 and, via a resistor 75 to which a diode 76 is connected in parallel, to the positive voltage source +U. The inverting input of the comparator 74 is connected to a voltage divider consisting of the resistors 77 and 78 and inserted between the positive voltage +U and ground. The outputs of the comparators 70 and 74 are interconnected and connected to the positive voltage source +U via a resistor 80. In addition, they are connected to the step motor output stage 56 through the line 57.
In the microcomputer 42 the switching voltages U 0 and U 1 are generated which are supplied to the step motor output stage 56 through lines 58 and 59. Controlled by the microcomputer 42, the switching voltages U 0 and U 1 may assume the value L or H (that is, low or high).
The line 58 is connected to the non-inverting input of a switching amplifier 81, and the line 59 to the non-inverting input of a second switching amplifier 82 in the step motor output stage 56. The line 57 is connected to the CE inputs of both switching amplifiers 81 and 82. They operate as switches to turn on and off or reverse the phase current I for the phase winding 49 applied between the outputs of the two switching amplifiers 81 and 82.
The positive terminals of the switching amplifiers 81 and 82 are connected through a line 83 to a positive voltage source +U B and their sensor terminals through the line 55 to a precision resistor 84 which communicates with ground. Resistor 84 acts as a discriminating element for output stage 56.
The arrangement operates as follows:
When an H signal is applied to either of the non-inverting inputs of the switching amplifiers 81 and 82 (FIG. 3), their output is connected through to the positive operating voltage whereas upon the application of an L signal their output is connected through to ground. If the chip enable input (CE) carries an L signal, the output becomes highly resistant, i.e. no current flows. The CE input serve to chop or switch off amplifiers 81 and 82.
Assuming the switching voltage U 0 of line 58 to be H, the switching voltage U 1 of line 59 to be L and the switching voltage U S of line 57 also be at the L level, due to the level L of line 59, the switching amplifier 82 is grounded. The H level of line 58 causes the switching amplifier 81 to become conducting as soon as the switching voltage U S of line 57 also switches to the H potential at the CE input (see also FIG. 4 at curve b). In this case, therefore, the phase current I begins flowing to ground from the positive voltage source +U B via the switching amplifier 81, the phase winding 49, the switching amplifier 82 and the precision resistor 84. A voltage drop is generated at the precision resistor 84 which is fed as actual voltage U I (FIG. 4 at curve c) via the line 55, the resistor 71 and the capacitor 72 with time delay to the comparator 70 where it is compared with the reference voltage formed by the control voltage U ST in line 53. When the actual voltage U I across the precision resistor 84 exceeds the control voltage U ST , the end of the charging phase is reached at time t 1 . The output of comparator 70 switches the switching voltage U S to L potential (FIG. 4 at curve b), and the two switching amplifiers 81 and 82 are shut off via the line 57 connected to their CE inputs. At the same time, this negative voltage surge is transmitted as switching voltage U S1 (FIG. 4 at curve d), through the capacitor 73 to the non-inverting input of the comparator 74, causing it to shift to L potential and keeping the switching amplifiers 81 and 82 shut off. Otherwise they would be turned on because no current is now flowing through the precision resistor 84.
Only after the capacitor 73 has been charged via the resistor 75 to the point where the switching voltage U S1 (FIG. 4 at curve d) at the non-inverting input of the comparator 74 exceeds the reference voltage U R applied to the inverting input by the voltage divider (resistors 77 and 78) at the time t 2 , the output of the comparator 74 shifts back to H potential. This causes the switching amplifier 81 to become conducting again through its CE input and the cycle described begins anew. The phase current I of the phase winding 49 is chopped, starting at time t 1 .
In this manner, the phase winding 49 is alternately switched to a relatively high voltage and separated from it after the desired current value I S is reached so that the energy stored in the phase winding 49 is fed back to the voltage source +U B via the recovery diode 85 in accordance with the law of inductance. Therefore, the current I continues to flow in the phase winding 49.
Whole steps are the result of the simultaneous excitation of both phase windings 49 and 49' (FIG. 1). If only one of phase windings 49,49' is energized between two adjacent whole steps, a half step results.
The phase current I of the phase windings 49 and 49' can be varied by the D/A converter unit 52 to increase the torque of step motor 31 during its motion phase, to improve the holding force of the step motor 31 in a half-step position and to correct the step setting within the preset step angle.
The phase current I of the phase windings 49 and 49' changes in proportion to the control voltage U ST . The level of the control voltage U ST is controlled by the microcomputer 42 (FIG. 3) in that the latter enters a correction factor into the buffer 48 through the data lines 47. In normal operation of the step motor 31 this correction factor will now remain at the output of the buffer 48 and, hence, also at the input of the D/A converter 60 until a new correction factor is put in, while the microcomputer 42, in the correction mode, applied to the buffer 48 alternately the correction factor and zero in a 1:1 ratio for reasons to be explained later.
The correction factor is converted in the D/A converter 60 into a corresponding level voltage, and the square wave voltage generated in the correction mode is filtered by the capacitor 64 so that the line 53 carries a relatively weakly pulsating control voltage. The control voltage U ST , reduced once more and smoothed once more greatly by the capacitor 68, can now be taken off the voltage divider 65 and fed as reference voltage to the comparator 70 via the resistor 69. The level of the control voltage U ST determines the rise time and, hence, the level of the phase current I (FIG. 4).
Predetermined, constant current values are assigned to the phase current I through suitable circuitry. In accordance with the correction factor applied to the buffer 48, the level of the phase current I is controlled to a current value +I H , -I H , +I V , -I V or to a current value between -I B and -I B (FIGS. 5 and 6). A positive sign indicates that the phase current I flows in one direction, a negative sign in the other direction determined by the control voltages U 0 and U 1 . If the control voltage U 0 and U 1 are the same, no current flows through the respective phase winding 49 or 49'.
FIG. 5 shows the current curve in the two phase windings 49 and 49' of the step motor 31 when executing eight whole steps in one direction and, after a pause, eight whole steps and one half step in the other direction. FIG. 5a indicates the curve of the phase current I in the phase winding 49 and FIG. 5b in the phase winding 49'.
At time t 0 the step motor 31 is in whole step position because phase currents I of the current value +I V flow through both phase windings 49 and 49'. In this whole step position the inputs 0,1 and 2 of the D/A converters 60 of both phase windings each carry H potential. Since both phase currents I are of the current value +I V , the holding moment is great enough.
At time t 1 the step sequence starts. The current flow in the phase winding 49' is increased to the current value +I H while the current flow in the phase winding 49 is reversed by the reversal of the control voltages U 0 and U 1 and increased to the current value -I H . This generates a higher torque to drive the step motor 31 in that the microcomputer 42 also applied H potential to the input 3 of the D/A converters 60 in addition to the inputs 0 through 2.
At time t 2 the current flow and the current value -I H in the phase winding 49 is maintained while the current flow in the phase winding 49' is reversed to the current value -I H . The step motor 31 is thus driven until, upon reaching the desired whole step position at time t 8 , the phase currents I of both phase windings 49 and 49' are reduced to the current value +I V .
For the step motor 31 to execute a revolution in the opposite direction, the phase current I of the phase winding 49 is increased to the current value +I H at time t" 1 while the current flow in the phase winding 49' is reversed and increased to the current value -I H . At time t' 2 the phase current I of the phase winding 49, having the current value +I H , is reversed whereas the phase current I of the phase winding 49' is maintained, etc. At time t' 9 , i.e. at the end of the second step sequence, the step motor 31 is in half step position in which the phase current I of the one phase winding, in this case the phase winding 49, is zero. The phase current I of the other phase winding 49 is, therefore, kept at its increased current value +I H in order to increase accordingly the holding force of the step motor 31, normally decreased in this position.
In FIG. 6 is shown the controlled correction between two whole step positions VS. The step setting between a whole step VS and the adjacent half step HS is corrected by dividing the step angle between them into seven intermediate steps. Since the step motor 31 in its intended operation works very much in its magnetic saturation, its angular deviation is no longer proportional to the current change. The result of measurements has been that proportionality of angular rotation and current change occurs in the present case only below half of the current value +I V of -I V of the phase current I, i.e. below +I B of -I B . Therefore, to execute a step correction in seven uniform stages, the current stage of the phase current +I V of -I V , preset by the microcomputer 42, is always cut in half. This is done by the already mentioned chopping of the correction factor at the outputs 0 through 2 of the buffer 48 by the microcomputer 42 (FIG. 3) in the pulse time to pause time ratio of 1:1. During the pulse time the buffer 48 contains the correction factor and during the pause time zero. After appropriate filtering by the capacitor 64 as well as the resistor 66 and the capacitor 68 the generated control voltage U ST is only of half the previous value.
If all inputs 0 through 3 of the D/A converter 60 of the one phase winding 49 or 49' carry L potential, making the correction factor zero while at the other phase winding 49 or 49' the correction value at the inputs 0 through 3 is of constant H potential, the step motor 31 adjusts to a half step HS. As FIG. 6 (position HS) shows, the phase current I of the one winding 49 is then zero and that of the other winding 49' is +I H , for example. The step motor 31 thereby changes its angle of rotation so as to adjust to the position HS in the middle between the two whole steps VS.
In the case of the whole step VS all inputs 0 through 2 of the D/A converters 60 of both phase windings 49 and 49' are switched to H potential. But when all inputs 0 through 3 of the one D/A converter is switched to L potential and all inputs 0 through 3 of the other D/A convertor 60 to H potential, a half step HS is present.
When a certain correction factor, chopped 1:1, is applied by the microcomputer 42 to the buffer 48 of the phase winding 49, e.g. H potential at the outputs 0 and 2 and L potential at the outputs 1 and 3 at positive phase current I and retention of the value +I V in the phase winding 49', the step motor 31 adjusts to the correction position of the angle of rotation ρ as shown in FIG. 6 by the identification 5. The same applies analogously to the adjustment into other correction positions.
If the step motor is to be stopped in a half step position HS, the input 3 of the D/A converter 60, whose inputs carry H potential in this case, stays on H potential in order to increase the holding amount of the step motor 31 which is lower in this position. To avoid too great an increase of the phase current I which would result from a current doubling, the voltage divider consisting of the resistors 61 and 62 is inserted so that the control voltage U ST is not doubled, but increased only by half the amount. This causes the phase current I of the respectively energized phase winding 49 or 49' to increase in the half step position HS from the current value +I V or -I V to the current value +I H or -I H , which still results in no heating problems in a permanent holding position of the step motor 31 in this position.
While a specific embodiment of the invention has been shown and described in detail to illustrate the application of the principles of the invention, it will be understood that the invention may be embodied otherwise without departing from such principles. | In a sewing machine with a microcomputer controlled step motor for the control of the magnitude and direction of the feeding action of a cloth feeder, the microcomputer is connected, via a buffer and a D/A converter, to the non-inverting input of a comparator which controls the turn-on and turn-off as well as the current intensity of each phase winding of the step motor and whose inverting input is connected to a discriminating element disposed in the phase circuit, for the step setting correction and for the torque intensification of the step motor. To adapt the correction possibilities to the step motor parameters, the D/A converter has four input stages whose biggest stage is connected to the corresponding output stage of the buffer via a voltage divider. | 3 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a semiconductor module such as a memory module. A “semiconductor module” herein refers to a module having one or more parts including a semiconductor package mounted on one substrate.
2. Description of the Background Art
Information equipment such as a personal computer has a memory module mounted as a semiconductor module. A common and conventional memory module will now be described. First, in FIG. 9, a semiconductor package 1 mounted on a memory module is shown. Semiconductor package 1 includes a package body 2 and a plurality of leads 3 protruding in parallel, respectively from opposing side portions. A dimension of semiconductor package 1 is determined by an organization for standardizing a semiconductor package, JEDEC (Joint Electron Device Engineering Council), and a “TSOP” (Thin Small Out-line Package) of “400 mil” is one example. When semiconductor package 1 is an SDRAM (Synchronous Dynamic Random Access Memory), 54 pins are provided, pitch A between leads 3 is set to 0.8 mm, and width B per one lead 3 is set to 0.3 mm.
As shown in FIG. 10, a memory module 100 has semiconductor package 1 mounted on a surface of substrate 4 in a prescribed arrangement. On the surface of substrate 4 , in addition to semiconductor package 1 , a packaged parts 5 a , 5 b such as a resistance, and a buffer IC (Integrated Circuit) 6 for amplifying and timing a signal of the memory are also mounted. In order to make effective use of a limited area on substrate 4 , packages are often mounted on opposing surfaces of substrate 4 , as shown in FIG. 11 . On both surfaces of substrate 4 , pads 7 are formed in positions corresponding respectively to leads 3 , which are electrically connected to pads 7 respectively. In an example shown in FIGS. 10 and 11, nine semiconductor packages 1 are mounted on one surface of substrate 4 of 133.35 mm long and 31.75 mm wide, which is a dimension determined in accordance with JEDEC standard. This means that, in total, eighteen semiconductor packages 1 are mounted on both surfaces.
As personal computers and the like are more sophisticated, an increase of memory capacity has been demanded. Accordingly, more semiconductor packages need to be mounted per one substrate. In an effort to achieve this, in Japanese Patent Laying-Open No. 4-276649, a technique to stack and mount a semiconductor package is proposed. According to the technique, as shown in FIG. 12, a semiconductor package 1 e having a longer lead is prepared in addition to semiconductor package 1 . As shown in FIGS. 13 and 14, a two-layered structure is provided on one surface of substrate 4 . That is, an inner pad 7 having a conventional arrangement and a pad 7 e arranged outside the former together form pads on the surface of substrate 4 . In the two-layered structure of the semiconductor packages, lead 3 of semiconductor package 1 located on a side close to substrate 4 (hereinafter, referred to as a “lower layer”) is connected to pad 7 , while a lead 3 e of semiconductor package 1 e overlying the former on a side far from substrate 4 (hereinafter, referred to as an “upper layer”) relative to semiconductor package 1 is connected to pad 7 e , going around the outside of lead 3 . In this case, however, a row of pad 7 e for upper layer semiconductor package 1 e should be arranged parallel to, and outside, a row of pad 7 for lower layer semiconductor package 1 . Therefore, width of the area occupied on substrate 4 will be larger. Consequently, for example, though nine semiconductor packages could conventionally be arranged per one layer on one surface of substrate 4 , only eight semiconductor packages per one layer on one surface can be arranged, as can be seen in a memory module 101 shown in FIG. 15 .
Further improved techniques are possible as described below. As shown in FIG. 16, a semiconductor package if is prepared, which is a 400 mil package having 54 pins in accordance with a conventional standard. Though pitch between leads 3 f is the same as a conventional example, width C per one lead 3 f is made smaller to 0.16 mm. This semiconductor package 1 f is provided as a lower layer. Separately, a semiconductor package 1 g is prepared having a lead 3 g that has the same length as lead 3 f when viewed from the top and has longer length than the same when viewed from the side. This package is provided as an upper layer. Width C per one lead 3 g of semiconductor package 1 g is also made smaller to 0.16 mm. Both packages are mounted, with one overlying the other, as shown in FIGS. 17 and 18. The pad of upper layer semiconductor package 1 g and the pad of lower layer semiconductor package 1 f are alternately arranged, and lead 3 g of semiconductor package 1 g is interposed between leads 3 f of semiconductor package 1 f respectively. Consequently, as can be seen in a memory module 102 shown in FIG. 19, nine packages can be arranged per one layer on one surface of substrate 4 , as in a conventional example.
In FIG. 20, an enlarged view of the vicinity of a root portion of the lead is shown. Generally, a plurality of leads protruding in parallel from a side portion of a package body of the semiconductor package are manufactured in the following manner. A package body 2 portion is formed with resin mold so as to partially cover a leadframe 14 integrally formed. Thereafter, as shown in FIG. 21, a punch region 13 set on a dambar 12 linking each lead in a portion protruding from the side portion of package body 2 is punched through, and thus each lead is separated. In an attempt to punch the region to completely remove dambar 12 linking each lead, a puncher may strike a lead portion and damage the lead, or useful life of the puncher may be shortened. Therefore, usually, punch region 13 is set to a size covering only a main portion of dambar 12 with a small clearance from the lead portion, not exactly covering both full ends of dambar 12 . Accordingly, as shown in FIG. 22, after punching, a dambar residual portion 8 will remain in the middle of lead 3 . Lead 3 is folded thereafter, to have a shape shown in FIG. 23 . In FIG. 23, the semiconductor package is shown, disposed on substrate 4 . Here, the lead can be divided in three parts: a lead drawn-out portion 31 horizontally drawn from the side portion of package body 2 ; a lead extending-downward portion 32 hereinafter, referred to as a “lead downward portion”) extending down to the surface of substrate 4 ; and a lead foot portion 33 for contacting pad electrode 7 .
A side view of the techniques described with reference to FIGS. 16 to 19 is shown in FIG. 24 . Width of the lead is made smaller in both upper and lower layers so that lead 3 g of upper layer semiconductor package 1 g passes a gap between leads 3 f of lower layer semiconductor package 1 f . In practice, however, as dambar residual portion 8 is present, the gap where lead 3 g can pass is narrow. Therefore, only a slight displacement of a position of either the upper or lower semiconductor package may cause a contact of lead 3 f with lead 3 g.
SUMMARY OF THE INVENTION
An object of the present invention is to provide a semiconductor module capable of increasing the mountable number of semiconductor packages per one layer on one surface of a substrate as well as avoiding contacts between leads due to a dambar residual portion.
In order to achieve the object above, a semiconductor module according to the present invention includes a substrate having a pad electrode on a surface, a lower layer semiconductor package mounted on the substrate, and an upper layer semiconductor package mounted on the substrate while arranged in a position substantially overlying the lower layer semiconductor package. The lower layer semiconductor package and the upper layer semiconductor package include a package body and a plurality of leads protruding in parallel respectively from opposing side portions of the package body and electrically connected to the pad electrode. The pad electrode having the lead of the upper layer semiconductor package connected and the pad electrode having the lead of the lower layer semiconductor package connected are alternately arranged. The lead includes a lead drawn-out portion horizontally drawn from a side portion of the package body, a lead downward portion extending from the lead drawn-out portion down to a surface of the substrate and a lead foot portion continuing to a tip end of the lead downward portion and contacting the pad electrode. The lead has a dambar residual portion protruding toward the lead adjacently protruding from the same package body in any position the middle between the lead drawn-out portion and the lead downward portion. An inner surface of the lead downward portion of the upper layer semiconductor package is positioned outside an outer surface of the lead downward portion of the lower layer semiconductor package. By adopting this structure, even if slight displacement of the relative positions of upper and lower layer semiconductor packages, with one overlying the other, may occur, contact of the lead of the upper layer semiconductor package with the dambar residual portion of the lower layer semiconductor package can be prevented.
In the present invention, preferably, when viewed two-dimensionally, the pad electrode is arranged in a staggered manner so that the pad electrode connected to the upper layer semiconductor package is located outside and the pad electrode connected to the lower layer semiconductor package is located inside, with a projection region onto the substrate of the package body serving as a center. By adopting this structure, while minimizing a material for the pad electrode, a connection portion to the lead can efficiently be arranged in a limited area.
In the present invention, preferably, a horizontal distance from the package body to the dambar residual portion in the upper layer semiconductor package is substantially equal to a horizontal distance from the package body to the dambar residual portion in the lower layer semiconductor package, and the lead downward portions of the upper layer semiconductor package and the lower layer semiconductor package extend diagonally relative to the substrate. By adopting this structure, contact between the lead downward portions can be prevented, even if the lead drawn-out portions are of the same length.
In the present invention, preferably, the lead has a section including the dambar residual portion, wider than other sections. By adopting this structure, a conventional punching apparatus can be used, obviating the need of a new punching apparatus.
The present invention preferably includes a structure in which a plurality of combinations of the upper layer semiconductor package and the lower layer semiconductor package are vertically stacked. By adopting this structure, larger number of semiconductor packages can be mounted in unit area of the substrate, and a semiconductor module of high density and high performance can be obtained.
The foregoing and other objects, features, aspects and advantages of the present invention will become more apparent from the following detailed description of the present invention when taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a plan view of a semiconductor package mounted on a semiconductor module in a first embodiment according to the present invention.
FIG. 2 is a side view of the semiconductor module in the first embodiment according to the present invention.
FIG. 3 is a partially enlarged plan view of the semiconductor module in the first embodiment according to the present invention.
FIG. 4 is a plan view of the semiconductor module in the first embodiment according to the present invention.
FIG. 5 is a partially enlarged side view of the semiconductor module in the first embodiment according to the present invention.
FIG. 6 is a partially enlarged side view of a semiconductor module in a second embodiment according to the present invention.
FIG. 7 shows a manufacturing process of a semiconductor package used in the semiconductor module in the second embodiment according to the present invention.
FIG. 8 is a side view of a semiconductor module in a third embodiment according to the present invention.
FIG. 9 is a plan view of a common and conventional semiconductor package.
FIG. 10 is a plan view of a first semiconductor module according to a conventional art.
FIG. 11 is a side view of the first semiconductor module according to the conventional art.
FIG. 12 is a plan view of a semiconductor package used in a second semiconductor module according to the conventional art.
FIG. 13 is a side view of the second semiconductor module according to the conventional art.
FIG. 14 is a partially enlarged plan view of the second semiconductor module according to the conventional art.
FIG. 15 is a plan view of the second semiconductor module according to the conventional art.
FIG. 16 is a plan view of a semiconductor package used in a third semiconductor module according to the conventional art.
FIG. 17 is a side view of the third semiconductor module according to the conventional art.
FIG. 18 is a partially enlarged plan view of the third semiconductor module according to the conventional art.
FIG. 19 is a plan view of the third semiconductor module according to the conventional art.
FIG. 20 is a first illustration representing a manufacturing process of a common and conventional semiconductor package.
FIG. 21 is a second illustration representing the manufacturing process of the common and conventional semiconductor package.
FIG. 22 is a third illustration representing the manufacturing process of the common and conventional semiconductor package.
FIG. 23 is a partially enlarged side view from a first direction, of the common and conventional semiconductor package.
FIG. 24 is a partially enlarged side view from a second direction, of the common and conventional semiconductor package.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
First Embodiment
Referring to FIGS. 1 to 4 , a structure of a semiconductor module in a first embodiment according to the present invention will be described. In the semiconductor module, a semiconductor package 1 f shown in FIG. 16 is provided as a lower layer while a semiconductor package 1 h shown in FIG. 1 is provided as an upper layer. Semiconductor package 1 h has a lead 3 h , of which width C is 0.16 mm. When viewed from the top, the lead of semiconductor package 1 h appears to be slightly longer than that of semiconductor package 1 f . Both of the above packages are mounted on a substrate 4 , as shown in FIGS. 2 and 3. When viewed in a direction of FIG. 2, lead 3 h appears to run outside lead 3 f . Note that a dambar residual portion is not illustrated in FIG. 2 .
As shown in FIG. 3, semiconductor package if and semiconductor package 1 h are stacked with a displacement by 0.4 mm, which is half the lead pitch A=0.8 mm. A pad 7 f for semiconductor package If and a pad 7 h for semiconductor package 1 h are arranged alternately, and at the same time, are staggered so that pad 7 h is located outside pad 7 f , when viewed from the package body. A memory module 110 is shown in FIG. 4 in its entirety.
Pad 7 h and pad 7 f corresponding respectively to the upper and lower semiconductor packages are not arranged in parallel in two distant rows as shown in FIGS. 13 and 14 but arranged in an alternate combination in a staggered manner. Therefore, horizontal width of a region occupied on substrate 4 by a set of vertically stacked semiconductor packages is not as large as that shown in FIGS. 13 and 14. Thus, as shown in FIG. 4, as in a conventional example, nine semiconductor packages can be arranged per one layer on one side of one substrate 4 with a dimension determined in accordance with the conventional standard.
In addition, as shown in FIG. 5, assume that lead 3 h of upper layer semiconductor package 1 h has 3 portions, that is, a lead drawn-out portion 31 h , a lead downward portion 32 h and a lead foot portion 33 h , and that lead 3 f of lower layer semiconductor package if has 3 portions, that is, a lead drawn-out portion 31 f , a lead downward portion 32 f and a lead foot portion 33 f . Here, an inner surface 35 h of lead downward portion 32 h of lead 3 h is positioned outside an outer surface of lead downward 32 f of lead 3 f . Therefore, even if slight displacement of the relative positions of upper and lower layer semiconductor packages, with one overlying the other, may occur, contact of lead downward portion 32 h of lead 3 h with dambar residual portion 8 f of lead 3 f can be prevented.
Second Embodiment
A structure of a semiconductor module in a second embodiment according to the present invention will be described. The semiconductor module has semiconductor package if mounted as a lower layer and semiconductor package 1 h mounted as an upper layer on substrate 4 , basically in a similar manner to the first embodiment, except for the shape of a lead of each semiconductor package as shown in FIG. 6 . Leads 3 f , 3 h have wide portions 10 f , 10 h respectively in the vicinity of the root when viewed from package body 2 . Dambar residual portions 8 f , 8 h are located in the middle of wide portions 10 f , 10 h respectively. Sides far from package body 2 of leads 3 f , 3 h are provided as narrow portions 11 f , 11 h . Width of the wide portion is 0.3 mm, which is the same as conventional lead width B, while width C of the narrow portion is 0.16 mm.
In addition to the effect described in the first embodiment, a portion of the lead is provided as a wide portion having the same width as the conventional lead width, whereby, the size of a region to be punched will be the same as in a conventional example (see FIG. 21 ), as shown in FIG. 7 . Thus, a conventional punching apparatus can be used, obviating the need for a new punching apparatus. Moreover, large width at the root portion will increase the strength of the lead itself.
In the present embodiment, leads of each semiconductor package in both upper and lower layers are provided with wide portions and narrow portions. Meanwhile, only the lead of each semiconductor package in the upper layer may be provided with the wide and narrow portions while the lead of each semiconductor package in the lower layer may have the conventional width, that is, the same width as the wide portion.
Third Embodiment
Referring to FIG. 8, a semiconductor module in a third embodiment according to the present invention will be described. In the semiconductor module, based on the concept in the first and second embodiments, the number of combinations of upper and lower layer semiconductor packages are increased, and a plurality of those combinations are stacked vertically (a top-to-bottom direction in the drawing) to the main surface of the substrate. In an example of a combination mounted on one surface of substrate 4 as shown in FIG. 8, though two combinations, that is, a combination of semiconductor packages 1 h , 1 f and a combination of semiconductor packages 1 j , 1 i are stacked, three or more combinations may be stacked. Further, the semiconductor packages stacked on one surface do not always have to be a combination of upper and lower layers. For example, a stack in which semiconductor package 1 j of FIG. 8 is absent is possible.
Thus, larger number of semiconductor packages are mounted per unit area of a substrate, and a semiconductor module of high density and high performance can be obtained. For example, if the module is a memory module, the one with a large capacity can be obtained.
According to the present invention, even if slight displacement of the relative positions of upper and lower layer semiconductor packages, with one overlying the other, may occur, contact of the lead of the upper layer semiconductor package with the dambar residual portion of the lower layer semiconductor package can be prevented.
Although the present invention has been described and illustrated in detail, it is clearly understood that the same is by way of illustration and example only and is not to be taken by way of limitation, the spirit and scope of the present invention being limited only by the terms of the appended claims. | A semiconductor module includes a substrate having a pad electrode on a surface, a lower layer semiconductor package mounted on the substrate, and an upper layer semiconductor package mounted on the substrate while arranged in a position substantially overlying the former. The pad electrodes connected to the leads of these semiconductor packages are arranged alternately. The lead has a dambar residual portion. An inner surface of a lead downward portion of the upper layer semiconductor package is positioned outside an outer surface of a lead downward portion of the lower layer semiconductor package. | 8 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This Application claims the benefit of U.S. Provisional Application 61/219,907, filed on Jun. 24, 2009 and incorporated herein by reference. This application is related to U.S. Application No. 12/822,826, filed concurrently herewith and issued on Dec. 20, 2011 as U.S. Pat. No. 8,079,352.
FIELD OF THE INVENTION
The invention is directed to materials and methods for lubricating and conditioning the rail/armature interface of an electromagnetic launcher, also known as a rail gun. More particularly, the invention is directed to lubricating and conditioning electrically-conducting rails and armatures before use and during launch.
BACKGROUND OF THE INVENTION
In electromagnetically-driven rail guns, two metallic rails in the gun barrel (bore) serve as electrodes that conduct current to a metallic armature wedged tightly between the rails. The armature is placed at the back of the projectile that delivers a payload. A fast, high-current pulse loops through the rails via the armature, generating a magnetic field that couples with the current passing through the armature to produce a force that accelerates the projectile down the barrel at supersonic speeds. Exemplary electromagnetic (EM) rail guns are described in U.S. Pat. No. 7,409,900. Nechitailo et al., issued Aug. 12, 2008; U.S. Pat. No. 7,077,047, J. F. Frasca, issued Jul. 18, 2006; U.S. Patent Application No. 20080053299, R. J. Taylor, publication date Mar. 6, 2008: and U.S. Patent Application No. 20070277668, J. F. Frasca, publication date Dec. 6, 2007: all of which are incorporated herein by reference. In presently-designed guns, it has been found that the both the rail and the armature are badly damaged by a combination of arcing, interfacial heating, frictional rubbing and gouging, leading to arc erosion, plowing wear and melting of either or both armature and rail. Although an armature is used only once, loss of armature material, e.g., Al from the low melting temperature Al armature, leads to contamination of rails with metal deposits and, worse, loss of contact between the remaining armature and rail. If the armature metal does not melt (e.g., Cu), arcing at the onset of sliding damages the rail by adding splats of eroded armature material, eroding rails at the arc strike location and oxidizing, via heating, areas surrounding the arc strike. As damage accumulates, the gun becomes less reliable on subsequent shots and bore life is diminished. The present invention will dramatically increase bore life by allowing projectiles to be fired hundreds of shots with minimal arcing and wear damage to both rails and armatures.
Lubrication is a primary approach for reducing damage to sliding contacts for electromechanical devices, however, there have been few efforts to date to determine the efficacy of lubricants in the specific application of rail guns. Traditional hydrocarbon lubricants are ineffective, both because they are non-conducting and ignitable. Solid lubricants based on graphite have been discussed in the literature, but none has been demonstrated to work effectively. One problem with graphite and metal-graphite solids is that their transfer films are patchy, and since graphite can be very resistive, patches can result in large voltage drops along the interface. Other solids like molybdenum disulphide and other dichalcogenides are lubricous, but not very conductive. Finally, the polymer polytetrafluoroethylene (“PTFE”—best known by the commercial name Teflon®) is a low friction material, but it is a poor conductor (as a bulk solid, it is 10 18 times less conductive than Cu). Thin conductive metal films can act as lubricants in solid vs. solid sliding contacts so long as the metal film has much lower shear strength than either metal. The problem remains of how to ‘coat’ the solids with the film run after run, which then presents another problem that hasn't been addressed of how to provide lubrication of the gun during or after each firing.
BRIEF SUMMARY OF THE INVENTION
According to the invention, in an electromagnetic rail gun launcher that includes a set of spaced-apart rails defining an inside bore for slidably receiving an armature-type projectile, with the rail gun and armature configured such that when powered up the projectile is forced from a breech of the rail gun toward a muzzle of the rail gun to then launch the projectile, the improvement wherein a lubricant reconditioning pad, containing a lubricant, is secured to the projectile in a location such that it contacts the rails. As the projectile moves through the bore, the pad cleans debris from, and applies lubricant to, the rails to thereby lubricate and recondition the rails during each shot.
For lubrication to be effective, the rail is preferably conditioned for the lubricant to be applied effectively to a surface, especially a just-shot surface. Conditioning removes contaminants that attach to or cover the rail: conditioning scrapes and textures the rail to make lubrication easier; and finally, conditioning treats the chemistry of the surface to accept lubrication.
The lubrication scheme disclosed herein affords better projectile performance and longer gun barrel life. The conditioning film provides better interface sliding, electrical contact and post-sliding protection to the rail.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an elevation view of a representative electromagnetic rail gun launcher to which the lubrication system and method are applied according to the invention;
FIG. 2 is a cross-sectional view of a rail gun track system with lubrication pads according to the invention;
FIG. 3 shows an armature-projectile with lubricating/conditioning pads according to the invention;
FIG. 4 shows an armature-projectile with lubricating/conditioning pads positioned fore and all of the armature according to the invention;
FIG. 5 is a graph comparing muzzle voltage vs. time for bare rails, conditioned rails and staples, and in situ conditioned rails and staples according to the invention;
FIG. 6 is a graph comparing projectile exit speeds for bare rails and in situ conditioned rails and staples according to the invention;
FIG. 7 shows photos of rails tested as in FIGS. 5-6 ;
FIG. 8 shows photos of the armature staples of the bare and the in situ runs for the tests of FIGS. 5-6 ;
FIG. 9 is a graph of speed vs. shot number for a series of 100 shots of in situ conditioned rails and staples according to the invention;
FIG. 10 is a schematic of the structure of FIG. 2 illustrating its operating functionality;
FIG. 11 is another schematic of the structure of FIG. 2 illustrating further details of its operating functionality; and
FIG. 12 is a graph showing vapor pressure curves of materials according to the invention.
DETAILED DESCRIPTION OF THE INVENTION
Referring now to FIG. 1 , an electromagnetic rail gun launcher 10 has a barrel 12 integrated into which are main rails 14 and 16 that are spaced apart so as to form a bore 18 therebetween for slidably receiving an armature 20 that to which is attached a projectile 22 , for example an electronic warfare countermeasure device such as a decoy to launch from a ship or an aircraft. Launcher 10 includes augmenting rails 24 , 25 , 26 and 27 separated from main rails 14 and 16 and one another by insulators 28 , 29 , 30 , and 31 . Rail crossover connectors 32 , 34 , 36 , and 38 electrically connect the sets of rails as shown such that when energized, current flows through the rails and a large magnetic field is generated. The armature 20 carries a current perpendicular to the magnetic field with a resultant force that acts on armature 20 to move from a breech 40 to a muzzle 42 of launcher 10 and thereby launch the projectile 22 at its design exit velocity.
Referring now to FIGS. 2-4 , in one embodiment the projectile 22 has a body 44 having a bullet-type geometry, that is, with a tapered nose portion 46 and where body 44 has a geometry so as to be fit into and be slidably received within bore 18 , which in the embodiment shown in FIG. 1 accepts a square cross-sectional body 44 (although of course it should be understood that other mutually compatible (projectile-bore) geometries are also within the scope of the present invention). Each of ten conductive copper wires is threaded into a hole drilled into the top surface 48 of projectile 22 at its aft end 50 and bent into a receiving slot milled into surface 48 that extends aft from the drilled hole to thereby form ten armature conducting contacts or “staples” 52 that together make up armature 20 (each contact is alternatively referred to as a “staple” because its geometry resembles a staple or at least part of a staple, in that it has a lengthwise portion, positioned in the milled slot, and one 90 degree bent end positioned in the drilled hole). Body 44 is fabricated from a nonconducting material, and for test purposes and ease of fabrication was Delrin®, a hard acetyl plastic material capable of withstanding the forces in the tested application. The exposed surface of each staple 52 was ground flat, then sanded with 400 then 600 grit carborundum (SiC) paper, then buffed to a bright finish by a cloth charged with rouge, and then cleaned with acetone. Staples 52 were then wiped with dilute acetic acid and then hand-rubbed with Rulon®, a lubricant and reconditioner further described below.
Body 44 also includes a Rulon insert lubricant and reconditioning pad 54 that serves to a) wipe and clean debris from the rail surface, b) texture the surface to reproduce an interfacial topography that optimizes electrical contact, and c) apply a fresh layer of lubricating film ahead of the armature/rail electrical contact. To insure that the reconditioning pad makes contact with the rail during the projectile's flight down the barrel, it should be relatively compliant for the following reason: After sliding begins, electrodynamic forces can subject the projectile to horizontal and vertical motions that displace the reconditioning pad from the rail. By choosing the proper compliance, the pad 54 will remain in contact with the rail during the projectile's flight down the barrel. Two methods of adjusting the compliance are proposed. First, the entire pad 54 should be spring-loaded against the rail by, for example, a thin piece of compliant rubber, e.g. rubber with elastic modulus from 0.2 to 20 MPa. This will insure that the pad 54 can remain in contact with the rail even when the armature and rail become displaced. A second method is to lower the compliance of the surface of the pad 54 at the sub millimeter scale. The reconditioning pad surface can be made much more compliant (softer) by ‘texturing’ the pad 54 . For example, one could cut narrow channels in the pad's surface with microtome blades or razor blades. This would create flexible sheets of the pad material some 0.1 to 2 mms tall, attached to the bulk of the pad 54 .
Finally, after sliding commences, the mechanical and electrical contact produced by the initial static loading of the armature against the rail will be augmented by electrodynamic forces. To maintain the maximum area of contacts between armature and rail during sliding, it is necessary to use armatures with multiple ‘fingers’ in contact with the rail; for example, an armature with a dozen solid wires instead of one solid piece of metal. A wire will be more compliant than a solid armature and will also move independently of the adjacent wire.
In addition to the one or more fore-mounted pads 54 projectile 22 may also include a pad 54 mounted aft, that is, in back of (with respect to the motion of travel through bore 18 ) armature 20 , that operates to wipe away debris and oxide formed at the staple/rail interface as projectile 22 traverses bore 18 .
Tests were conducted to compare the performance of launcher 10 with and without the above-described lubricating and reconditioning means. FIG. 5 is a graph of muzzle voltage vs. time for seven-shot tests on a) a bare copper armature, b) a preconditioned copper armature, and c) an in situ conditioned copper armature, that is, one that included a pad 54 as in the configuration of FIGS. 2-3 . The untreated (bare) armature produced three broad, high voltage spikes, the preconditioned armature two smaller spikes, and the in situ conditioned armature produced no spikes. FIG. 6 is a graph of the projectile exit speed vs. shot number for the same tests, comparing just the bare and the in situ results. The former shows a marked decrease in exit speed with shot number increase due to the damage on the staples and/or rails. The speeds of shots with in situ conditioned rails remained high, and actually increased with shot number, due to decreased rail damage from wear and arcing.
FIG. 7 shows photos of the midsection of the three left-side (negative polarity) main rails from the same tests, and it as evident that the bare rail had more shards of broken-off armature copper than either of the Rulon-conditioned rails, with the in situ conditioned rail having the fewest shards and being much less degraded. FIG. 8 show photos of the wear on the staples for the bare and the in situ tests. After one shot on the bare rail, the armature staples (top) already exhibit arc damage, brown deposits, abrasive scratches and eroded pits surrounded by smooth metal (circled areas). The bottom photos of the in situ test staples are after seven shots and show almost no wear to the armature staples.
Table 1 compares the performance of the bare and in situ conditioned copper rails and staples:
TABLE 1
Parameter
Bare Cu
in situ conditioned Cu
Speed
Decreased 50%
Increased 7%
Muzzle voltage vs.
Several big spikes
No spikes
time
Armature/rail damage
Arc damage, metal
No arc damage, much
transfer, staples wore off
less metal transfer,
staples intact
Tests were subsequently run with in situ conditioned copper rails for a series of 100 shots, with the results shown in FIG. 9 . The projectile exit speed remained nearly constant, with a mean exit speed of 137 m/s. The two lower-speed results around shot 40 were caused by a broken staple that was repaired for the subsequent shots.
Referring now to FIG. 10 , in another embodiment a resistive metal foil strip 47 coated with low-vapor pressure metals is positioned on the armature 20 as shown such that the metal foil strip 47 contacts the rails 14 and 16 . The current through the strip 47 provides the thermal energy to vaporize the metal and thus lubricate and protect rails 14 and 16 for subsequent shots. Accordingly, the vaporization occurs as the armature 20 heats up. FIG. 11 illustrates both embodiments together. FIG. 12 shows vapor pressure curves for exemplary metals useful as reconditioning lubricants. The predicted temperature profile of the armature 20 can accordingly be employed to select which low-vapor pressure metals should be applied in a given location. To insure that the preconditioned armature surface maintains a sufficient reservoir of solid lubricant, the armature should be ‘textured’ (by machining or abrasion). When the conditioner is rubbed onto a textured surface, solid lubricant will fill the valleys, which will act as a reservoir of solid lubricant. As the initial transfer film degrades, lubricant in the valley will be supplied to the contacts. Texturing that creates a peak-to-valley roughness between 0.1 and 1 micrometer suffices for rail guns up to 10 m long.
Referring again to FIG. 12 , shown are metals with high vapor pressures at relatively low temperatures. Such vapors condense to form thin metal films that are softer than the armature/rail couples, e.g., Ag for Mo vs. Mo, and thus provide a lower shear-strength interface—hence lower friction coefficient—than the original armature/rail interface. Foils of these metals are placed either in front of the projectile or behind the projectile. As the projectile gets hotter, the foils disperse metallic vapors at the temperatures and rates shown. A second method of inducing vapor lubrication is to put an electrically resistive sheet on the front of the projectile, but in contact with the two rails. The sheet is preferably coated with a high vapor-pressure metal as discussed. As the sheet heats up (controlled by the sheet's resistance and rail voltage—6 to 20 volts typically, the metal evaporates and deposits ahead of the projectile.
A second class of material used as vapor phase lubricants are chosen to react with the rail surface to form lubricous layers. Sulfur, for example, can be used to form MoS 2 on Mo rails or to form WS 2 on W rails. A third class of material used as vapor phase lubricants can be known gunpowder additives (a prior art). They are dispersed by mounting behind the projectile a charge containing the additives then detonating the charge at selected locations down the barrel. The location can be chosen to place the vapor phase lubricants only where needed.
Composites can also be used as conditioners/lubricants. These include fiber-reinforced PTFE-based composites capable of withstanding temperatures to 400 C.; and, higher temperature composites (up to 800 C.) that contain soft metals, ceramics and high-temperature lubricating phases. Both materials are commercially available.
The PTFE-based composite was tested in preconditioning rails and armatures and as a reconditioning pad in a low velocity rail gun application. Using the methods discussed above, the PTFE-based composite protected Cu rails from virtually all metallic transfer that was deemed responsible for sliding damage and arcing damage to rails.
Regarding PTFE-formed SLIC films such as Rulon, it is advantageous that the matrix material is an intrinsically slippery material such as PTFE. Once a layer of PTFE transfers to a surface. PTFE does not transfer to any extent on top of that layer because PTFE has such a low surface energy, such that little, especially PTFE, adheres to it. A surface rubbed with pure PTFE, however, may accumulate thicker patches of PTFE fragments, due to unstable shear of PTFE. Rulon is a composite material containing both the abrasive phase and the SLIC phase, e.g. Rulon A (or Rulon AMR or Rulon LR), which contains upwards of 20% glass fibers (abrasives) in a PTFE matrix and may contain a few percent solid lubricant MoS 2 as well.
To avoid the latter, the composite should contain a percentage of finely-dispersed hard particles or whiskers that perform two functions. First, they will strengthen the matrix and prevent it from wearing fast. An example would be glass fiber reinforced PTFE, whose wear rate is 103 to 104 smaller than bulk PTFE. Moreover, since the harder particles will protrude from the softer matrix, the particles will behave as second-body abrasives that both thin out patches of transferred matrix material and plow transfer films into the metallic surface. Finally, a small percentage of a third phase of a very low friction material should be added act to reduce adhesion of the matrix to the rubbed surface. The latter will not be the dominant lubricous phase; however, it will make it easy to spread and transfer lubricant to the metallic surface. The third phase can be MoS 2 (or WS 2 or WSe 2 ) in a PTFE composite or a soft metal like Ag in a high temperature lubricant composite.
Thin transfer films of lubricant like PTFE protect rail gun surfaces in many ways. A projectile spends less time in the breech if the static friction at start up is reduced. With the armature out of the starting gate sooner, the breech is less likely to be damaged during the initial high current pulse. A low friction film intervening between the sliding armature and the rail reduces the chance of metallic adhesion between the sliding couple, thereby reducing the transfer of metallic shards from the hotter (thus weaker) armature surface and the rail surface. PTFE has a very low surface energy (w=0.02 mJ/m 2 ) compared to metal oxides (w=1-5 J/m 2 ). Low surface energy, w, not only reduces the adhesion of a surface (to contaminants as well as other metals), it also decreases the force necessary to release shards of that might have attached to its surface (from sliding wear or arc erosion). The latter process is significant, as the release force (technically, fracture initiation force) scales as √w. Shards attached to rails will scratch armatures and promote arcing contacts. With fewer shards on the rail, subsequent shots are less likely to degrade the barrel.
In addition, thin PTFE transfer films protect rail surfaces in other ways. First, the very thin dielectric film increases the electrical conductivity of the rail/armature interface. A PTFE film, squeezed to a thickness of a nanometer or so by asperities loaded in contact, reduces the work function of the junction, thereby increasing the electrical conductivity of the Cu-film-Cu junction below that of Cu—Cu oxide-Cu junctions. Secondly, the PTFE fills the deeper valleys (roughness) where direct contact is unlikely. The PTFE in the valleys acts to: 1) suppress arcing (PTFE is an arc suppressant); 2) reduce oxidation of the metal surfaces heated by the local current; 3) minimize wetting of the rail by molten metal; and 4) act as a reservoir of PTFE in case local areas become worn down. Finally, the process of rubbing the composite against the rail (and armature) cleans the surface of debris, burrs and adventitious surface films accumulated during preparing the rail for assembly.
A second class of composites useful as conditioners contains phases that provide both low friction and mild abrasion over a wide temperature range, from 25° C. to 800° C. The NASA composite, designated as the PS300 series, is a good example. These are composed of phases that are mildly abrasive but provide low friction in sliding contact over the temperature range from 25 C. to 800 C. We have conducted room temperature sliding tests with steel sliding against hard steel (52100) or a Cr-plated steel. When PS300 composites were used as transfer pads, metal-to-metal wear was reduced dramatically. The PS300 series composites are very hard (10-12 GPa), harder than hardened steel. This makes them well suited as conditioning pads for very hard rails or rails surfaced with hard-coatings, like Cr plating. Also, because they remain lubricous up to 800 C., they can be placed on or very near the metal armature and allowed to heat up. Table 2 lists the above two composites and some of their properties.
TABLE 2
Conditioner for Rail Guns
Friction
NAME/CLASS
COMPOSITION
T max (C.)
Coefficient
PTFE-based
PTFE + glass fibers +
400
0.1-0.2
composite 1
5% MbS 2
NASA PS300
60% Cr 2 O 3 . 20% NiCr
800
0.2-0.3
series 2
and 10% each of Ag
and BaF 2 /CaF 2 eutectic
1 San Gobain, JPM (Hattiesburg. MS) and others
Table 3 lists several other materials that have been used as protective coatings for high speed or high temperature sliding. Intercalated graphite and the Westinghouse compact could be used as matrix materials for lubricous composites and thin metalized diamond-like carbon could be used as low-friction, protective films on one-shot armatures.
TABLE 3
Solid lubricant for Rail Guns
Friction
Coef-
NAME/CLASS
COMPOSITION
Tmax (° C.)
ficient
Intercalated Graphite 1
CdCl 2 -graphite
700
0.1-0.2
CrCl 3 -graphite
800
“Westinghouse
90% WSe 2 /10% Ga—In
650
0.1-0.3
Compact” 2
Metallized
C:H:Me where Me =
500-800
0.1-0.2
Diamond-like
Ag, Si, W, Ti, . . .
Carbon 3
1 DARPA report WRDC-TR-90-4096 (Final report for September 1985 to September 1989, Vol. 1, Summary)
2 DARPA report AFWAS-TR-83-4129 (Final report covering 1978-1983, part 2, Vol. 1, Summary)
3 Commercially available from several manufacturers
Obviously many modifications and variations of the present invention are possible in the light of the above teachings. It is therefore to be understood that the scope of the invention should be determined by referring to the following appended claims. | In an electromagnetic rail gun launcher that includes a set of spaced-apart rails defining an inside bore for slidably receiving an armature-type projectile, with the rail gun and armature configured such that when powered up the projectile is forced from a breech of the rail gun toward a muzzle of the rail gun to then launch the projectile, the improvement wherein a lubricant reconditioning pad, containing a lubricant, is secured to the projectile in a location such that it contacts the rails. As the projectile moves through the bore, the pad cleans debris from, and applies lubricant to, the rails to thereby lubricate and recondition the rails during each shot. | 5 |
FIELD OF THE INVENTION
[0001] The present invention is related to the field of metallized packaging substrate needing a partially demetallized area and more particularly to a simplified process for obtaining the same.
TECHNOLOGICAL BACKGROUND
[0002] In flexible packaging applications, polymeric films and/or paper webs are often combined to a metallic layer generally consisting of aluminium. This metallic layer can be a self-supporting foil, typically between 6 and 15 μm thick, or it can be a much thinner layer, generally below 0,1 μm thick, on a polymeric or paper support. This metallic layer is usually applied by a vacuum coating process, in which vaporised metal atoms adhere to a suitable substrate. This vacuum metallization process is extensively described in the literature.
[0003] Metal foils and metallic coatings have several functions, including barrier functions with regard to atmospheric gases, water vapour, radiation, etc. and, in addition, play an important role in the marketing aspects of a package. Such metallic layers give a particular brilliance and colour intensity to the overlying printed design, and, where visible by themselves as a metallic design element, give a perception of quality and protection of the package contents. In many cases though, when the barrier needs of the package allow it, the producer would wish to combine these positive marketing aspects of a metallic layer with a partial window in the metallic layer. In the case of transparent polymeric films the main purpose would be to allow for visual inspection of the packaged product by the consumer in the retail phase. In the case of multilayer structures involving paper or other non-transparent substrates, there might be other functional or marketing advantages in having a partial window in the metallic layer.
[0004] In most of the following, we focus on the case of transparent polymeric film laminates with thin metallic coatings as being the most important class of multilayer materials in which the current invention could be applied. Here the current industrial practice for obtaining a partial demetallization has been a procedure involving the following processing steps:
a) a printing step, involving a metallized film, typically consisting of an oriented coextruded polypropylene film, between 15 and 30 μm thick and vacuum coated with a layer of aluminium, about 100 to 1000 Å thick, which is partially printed on a regular printing line (typically a gravure or flexo press) using a suitable ink system and an overlacquer to protect the inks during subsequent processing. In most cases, a primer is applied between the metallized layer and the printing inks to improve adhesion. When this printed film is intended for partial demetallization, care is taken that neither primers nor inks or overlacquers cover the aluminium in the area to be demetallized. In the case that an unprinted metallized film is intended to be partially demetallized, only the protective overlacquer would need to be printed, possibly with the addition of a suitable primer; b) a demetallization step, involving the passage of the film prepared according to step (a) through a concentrated sodium hydroxide (NaOH) solution in water, whereby the exposed portions of the metallic aluminium are dissolved and the dissolved metal is subsequently washed away with water, followed by a drying operation to remove excess moisture; c) a lamination step, whereby the printed demetallized film is taken on a laminating machine and bonded to another self-supporting film web, typically 15-30 μm thick, using a suitable adhesive system (most often a two-component polyurethane adhesive).
[0008] The procedure described above and in practical use today is seen to involve at least three separate converting steps, which makes it a very costly process, limiting its market penetration to high-end products. A further disadvantage is the time loss because of the logistics of the three-step process, especially if converting and demetallization equipment are found in different production sites. A further disadvantage is the fact that particular in-line operations, such as the application of a cold seal lacquer on the backside of the metallized film, become impossible because of the various processing steps. A further disadvantage is the lack of an optimal quality control in the printing step, since the final result only becomes visible after the demetallization step.
[0000] State of the Art
[0009] The above multi-step procedure being the current industrial practice, we believe that the following documents represent the closest prior art.
[0010] U.S. Pat. No. 5,628,921 describes a process for carrying out the classical demetallization involving a caustic solution and a washing step, in-line with a gravure printing operation, through the use of a dedicated machinery custom made for this purpose and essentially consisting of a classical demetallization equipment connected to a classical gravure printing press. It would seem that this process and equipment has the advantageous possibility of in-line quality control checking the demetallized area in respect of the printed design, this is however achieved at the expense of a much higher investment cost for this complicated machinery.
[0011] U.S. Pat. No. 3,647,508 discloses a process for carrying out the demetallization whereby the etching agent is mixed with a film-forming dispersion thereby achieving that the etching agent can be contained within a dried coating remaining on the web. However this method only claims particular effects on the conductivity, reflectivity and adhesion of the final product, not transparency, and an optional washing step is described evidently for this purpose.
[0012] The purpose of the present invention is to obtain clarity and transparency (high transmission and clarity and low haze) of the demetallized window, which still requires a washing step in the prior art.
[0013] In summary, neither of the two described processes constitutes a significant breakthrough versus the current practice described in the technological background.
[0000] Aims of the Invention
[0014] The present invention aims to provide a simplified process for partial demetallization of flexible substrates, performed on standard equipment such as a gravure or flexo press, rather than on machinery specifically designed for demetallization. Furthermore, this invention aims to reduce complexity and cost of the entire process by performing said process in-line with other converting operations such as printing, laminating and/or coating in one continuous operation.
SHORT DESCRIPTION OF THE DRAWINGS
[0015] FIG. 1 represents a metallized film complex comprising different components according to a first embodiment of the present invention;
[0016] FIG. 2 represents a metallized film complex comprising different components according to a second embodiment of the present invention;
[0017] FIG. 3 represents a metallized film complex comprising different components according to a third embodiment of the present invention;
[0018] FIG. 4 represents a standard process machinery able to achieve demetallized film according to anyone of the embodiments of the present invention.
SUMMARY OF THE INVENTION
[0019] The present invention discloses a continuous process for the partial demetallization of a first multilayer substrate, comprising at least one metallic layer, characterised in that a designed lacquer comprising at least one metal dissolving etchant, locally reacts with said metallic layer and that the dissolved metal remains within said multilayer structure and that the dissolution of the metal allows the creation of a window in said metallic layer without the necessity of a washing step and in that said partial demetallization is suitable to be carried out on standard gravure or flexo printing presses or coating equipment.
[0020] A possible embodiment of the present invention is that said process further comprises a lamination step of the partly demetallized multilayer support with at least one second substrate.
[0021] Furthermore, the present invention discloses that at least one of said substrates is selected from the group consisting of polymeric films, paper, metallic foils and non-woven substrates.
[0022] Another possible embodiment is that at least one of said substrates is treated by at least one coating operation and/or at least one printing operation.
[0023] The present invention also shows that said coating or printing operation is carried out on a different substrate surface than that where the demetallization is carried out, yet involves a patterned print or coating in register with the demetallized area and/or the other printed designs in or on the multilayer structure.
[0024] Another key feature of the present invention is that the demetallization step achieves a light transmission of at least 90% within the demetallized area without a washing step.
[0025] Furthermore, the demetallization step to obtain a light transmission of at least 90% is carried out on standard gravure or flexo printing presses or coating equipment without necessitating specific dedicated equipment for demetallization.
[0026] Another key feature of the present invention is that the etchant concentration in the etchant lacquer substantially corresponds to the stoechiometrical amount of said etchant to dissolve the amount of metal present on the film.
[0027] Alternatively, the etchant concentration in the etchant lacquer corresponds to a slight excess of the stoechiometrical amount of said etchant to dissolve the amount of metal present on the film.
[0028] Finally, the present invention discloses a multilayer support obtainable by any of the previous claims comprising windows in continuous and/or discontinuous supported metallic layers characterised in that said windows contain the total quantity of the residues resulting from the demetallization by means of an etching product.
DETAILED DESCRIPTION OF THE INVENTION
[0029] The present invention discloses a process for partial demetallization, whereby the etching agent is contained in a suitable formulated lacquer which can be applied onto the metallized web using commonly available film converting equipment (such as a gravure or flexo press or coating line) and said lacquer is designed to remain in contact with the web, thereby also retaining the dissolved metal in place, such that the need for washing and drying the demetallized part of the web is eliminated while simultaneously achieving optimal clarity and transparency of the demetallized area.
[0030] The following measurements have been achieved on a suitable equipment specified hereunder to show the high transparency reached on samples realised according to the process of the present invention:
[0000] Equipment: Haze-Gard plus
[0000] Measurement: according to norm ASTM-1003
[0000] Results:
[0000]
(a) on a demetallized laminate:
transmission=94.1%±1.2% haze=4.7%±0.6% clarity=96.1%±0.4%
(b) on a transparent laminate:
transmission=94.9±1.0% haze=3.7±0.3% clarity=96.2±0.3%
[0039] The results show that only negligible differences exist between the demetallized samples and ordinary transparent laminates.
[0040] The process achieves the demonstrated transparency by a combination of two actions, the first being the elimination of chemical reactivity of the etchant versus the adhesive layer it contacts in the region of the transparent window, by fine-tuning the amount of etchant lacquer applied onto the metallization through choosing a suitable gravure cylinder depth and adapting the etchant concentration in the wet etchant lacquer as needed, thereby being close to (and only slightly towards excess of) the stoechiometrical amount of etchant needed to completely dissolve the amount of metal present on the film; and a second action being the elimination of any chemical reactivity of the etchant towards the same adhesive which could result from an interaction on the machine between the etchant lacquer and the wet adhesive which would be expected to result in a partial dissolving of the etchant lacquer into the adhesive-containing vessel on the laminating section, at which time the etchant is seen to chemically react with the adhesive.
[0041] This invention by itself means a major simplification and cost saving of the demetallization step, since it can now be performed on commonly available equipment rather than on machinery specifically designed for demetallization. Furthermore, this invention immediately gives rise to a further significant reduction in complexity and cost of the entire process, since the demetallization step can easily be performed in-line with other converting operations such as printing and laminating, in one continuous operation. This has the added advantage of allowing immediate control of the demetallized result such that an adjustment in an earlier process step (e.g. the printing position of the protective overlacquer) can be easily made.
[0042] A further advantage is the possibility of carrying out particular operations or applying particular products which previously could not withstand the step of demetallization/washing/drying, or were impossible because the lack of registration between the printed design and this additional product, an example being the application of a lacquer on the outside of the laminate in a fixed position with regard to the printed design.
[0000] Description of a Preferred Embodiment of the Invention
[0043] In the first embodiment of the present invention, as represented in FIG. 1 , the metallized substrate 20 as defined above, is partially printed using a suitable ink system 23 , typically with the aid of a primer 22 to improve ink adhesion on the metallization 21 , and a protective overlacquer 24 on the printed areas. The demetallization in the unprotected areas is achieved by applying a demetallization lacquer 25 containing the etching agent onto the remaining exposed surface of the metallization. This is done in-line with the printing step, and can on suitable printing presses be followed by an in-line laminating step using a suitable laminating adhesive 26 as above. When using solvent-based adhesives it will be advantageous to apply the adhesive to the non-printed web so that the wet adhesive 26 and the solvents contained therein cannot affect the printing inks 23 and especially the demetallization lacquer 25 .
[0044] In a second embodiment of the present invention, represented in FIG. 2 , the process could be set up so that first the demetallization lacquer 25 is locally printed on the metallized layer, followed by an all-over coated protective lacquer 24 , now also covering the demetallization lacquer, and then by the printing inks 23 where intended. Again the finalisation of the laminating step can be done in-line. This alternative procedure would have the added benefit of allowing, for marketing reasons, part of the printed design not be backed by the metallic layer, thereby giving a distinctive change in appearance.
[0045] In a third embodiment of the present invention represented in FIG. 3 , an ink type 23 is used which resists (is not chemically affected by) the etchant 25 , but is not a barrier to it, together with a metallization primer 22 which is a barrier to said etchant. In this embodiment the protective overlacquer 24 is not needed. As in the second embodiment, this one allows inks to be backed by metal or by transparent film, and achieves this extra capability even while requiring less gravure positions. If required, other converting operations remain possible in-line.
[0046] While the invention has been illustrated and described in what are considered to be the most practical and preferred embodiments, it will be recognised that many variations are possible on the positioning of the different layers and come within the spirit and scope thereof, the appended claims therefore being entitled to a full range of equivalents (inks can be omitted, coatings added, and generally several possible positions are possible for each component of the multilayer structure). Known possibilities, which are also not further explored here, include making a partially demetallized multilayer structure containing only one self-supporting substrate, or alternatively three or more of such substrates, as well as having a metallization layer 21 not directly supported by a substrate but rather applied onto a coating and/or printing ink. Furthermore, completely similar multilayer structures can be made using paper and/or pigmented films, either metallized or not, in such multilayer structures in which case no transparency of the total structure is achieved, but the optical clarity of the demetallized layer itself might be just as appreciated.
[0000] Example of a Demetallization Process According to the First Embodiment of the Present Invention
[0047] During the process, a reel of polymeric film 20 , typically consisting of biaxially oriented polypropylene and metallized on one side with a layer of vacuum deposited aluminium 21 , is placed in the unwind position 11 of a heliogravure press with in-line laminating capability. The film runs through consecutive gravure printing stations 1 to 6 of the machine, and undergoes the following consecutive operations:
a) in gravure station 1 the entire portion of the metallization layer 21 which is intended to remain on the final material, is coated with an adhesion-promoting primer 22 , b) in stations 2 , 3 and 4 the individual colours of the printing design 23 are printed on the film, c) in station 5 the printed area 23 is covered by a protective overcoating 24 , d) in station 6 the remaining portions of uncovered metallization 21 are covered with the demetallization lacquer 25 . As the intended chemical reaction takes place, the part of the metallized layer 21 in contact with the demetallization lacquer 25 becomes transparent. From unwind position 12 , a second reel of film 27 is unwound, typically consisting of a transparent biaxially oriented polypropylene, and passes through gravure station 7 in which a layer of adhesive 26 is applied to the inside surface of the film, after that, the adhesive-coated web passes through a drying oven 10 in order to dry the adhesive, before being joined in the laminating nip 8 to the other web (the partially printed, partially demetallized film) thereby making the final laminate which is wound up in position 13 .
Example of Demetallization Lacquer
[0052] The demetallization lacquer is generally a hard base such as NaOH or KOH dissolved in water or any other possible etching agent combined with a film forming dispersion agent, also called encapsulating agent, such as nitro-cellulose encapsulating said hard base. The compatibility between the etchant and dispersion agent is determinant. Other possible additives are usual processing additives such as anti foaming agents.
[0053] A series of demetallization lacquers are given in U.S. Pat. No. 3,647,508 and can be adapted to the process of the present invention.
[0054] In summary, this invention has the following innovative aspects and advantages:
the process achieves optimal clarity and transparency of the demetallized area while eliminating the need for a washing step previously considered necessary for such effect even when using a demetallization lacquer designed to hold both the active agent and its reaction product locked inside the multilayer structure. printing, demetallization and laminating can be done in-line on commonly available converting equipment, eliminating the need for a dedicated demetallization line. the in-line process, besides being much more efficient and cost-effective, allows for more adequate quality control on the final product allowing for adjustments in each of the previous steps to be implemented immediately. this process allows for in-line coating on the outside of the laminate, e.g. a coldseal lacquer, in register with the printed design.
[0059] Nomenclature
1 - 6 : gravure stations 7 : adhesive-coating station 8 : laminating nip 9 : gravure drying oven 10 : adhesive drying oven 11 : unwind film 1 12 : unwind film 2 13 : rewind laminate 20 : film substrate layer 1 21 : metallic layer 22 : primer 23 : printing ink 24 : protective overlacquer 25 : demetallization lacquer 26 : laminating adhesive 27 : film substrate layer 2 | The present invention discloses a continuos process for the partial demetallization of a first multilayer substrate, comprising at east one metallic layer 21 , characterised in that a designed lacquer comprising at least one metal dissolving etchant 25 , locally reacts with said metallic layer 21 and that the dissolved metal remains within said multilayer structure and that the dissolution of the metal allows the creation of a window in said metallic layer without the necessity of a washing step and in that said partial demetallization is suitable to be carried out on standard gravure or flexo printing presses or coating equipment. | 2 |
The invention herein described was made in the course of or under a contract, or subcontract thereunder, with the United States Department of the Air Force.
BACKGROUND OF THE INVENTION
This invention relates generally to gas turbine engines and, more particularly, to a thermally actuated control arrangement for maintaining minimum clearance between a rotor and surrounding shroud.
In an effort to maintain a high degree of efficiency, manufacturers of turbine engines have strived to maintain the closest possible clearance between the engine rotor and the surrounding stator structure, since any gas which may pass therebetween represents a loss of energy to the system. If a system were to operate only under steady-state conditions, it would be a simple matter to establish the desired close clearance relationship between the rotor and the stator to obtain the greatest possible efficiency without allowing frictional interference between the elements. However, in reality, all turbine engines must initially be brought from a standstill condition up to the steady-state speed, and then eventually decelerate to the standstill condition. This transitional operation is not compatible with the ideal low clearance condition just described since the variation in rotor speed also causes a variation in the size thereof because of mechanical expansion caused by centrifugal forces. The stationary stator, of course, does not grow mechanically and there is, therefore, relative mechanical growth between the two structures during periods of transitional operation. Further, as the turbine engine is brought up to speed from a standstill position, the temperature of the gas passing therethrough is increased proportionately, thereby exposing both the rotor and the stator to variable temperature conditions. These conditions cause thermal growth of the two structures, and if the two structures have different thermal coefficients of expansion, which is generally true, then there is also the occurrence of relative thermal expansion between the elements. Characteristically, a rotor is necessarily a large mass element which allows it to rotate at very high speeds, thereby inherently yielding a very slow thermal response (high thermal inertia). On the other hand, the stator is a stationary element and preferably has a high thermal response (low thermal inertia) to allow for thermal growth of the stator during periods of acceleration to accommodate the mechanical growth of the rotor during those periods.
In many turbine engine applications, there is a requirement to operate at variable steady-state speeds, and to transit between those speeds as desired in the regular course of operation. For example, in a jet engine of the type used to power aircraft, it is necessary that the operator be able to transit to any desired speed whenever he chooses. The resulting temperature and rotor speed changes therefore bring about attendant relative growth between the rotor and stator which must be accommodated for. As mentioned hereinbefore, a primary concern is to maintain the minimum clearance between the stator and rotor of the engine while preventing any frictional interference therebetween.
A typical cycle through which an aircraft jet engine operates begins with a "cold rotor burst" by which the engine transits from an idle operating condition to a maximum speed condition. The high thermal inertia rotor quickly grows by reason of its mechanical expansion, and slowly grows thereafter because of thermal expansion, until it reaches a steady-state diameter. The stator, on the other hand, grows quickly because of its relatively lower thermal inertia, to thereby provide room in which to allow the rotor to grow. Assuming that the jet engine reaches a steady-state maximum speed operating condition, the next speed transition may come about by a "throttle chop", by which the engine is again brought back to idle speed. When this occurs, the rotor immediately and quickly shrinks mechanically, and then continues to slowly shrink by reason of the change in temperature. The stator, on the other, hand experiences no mechanical shrinkage but begins to thermally shrink at a relatively fast speed. If the operation now calls for maximum throttle at the time the stator reaches its steady-state, reduced size, then the rotor will immediately mechanically expand to a larger size than when it experienced a "cold rotor burst." Since the stator has shrunk faster and farther than the rotor, it is during this period of operation that the clearance between the two elements is at a minimum and is therefore a critical criteria for the design of an aircraft jet engine. If the thermal response of the stator is reduced to cause a slower shrinkage thereof, and thereby accommodates a slower shrinkage of the rotor, then the required quicker expansion characteristics during periods of acceleration would be hampered. For example, if after the "throttle chop", the throttle is again brought up to maximum speed (hot rotor burst), then the stator must be capable of quickly expanding to accommodate the mechanical expansion of the rotor.
It is therefore an object of this invention to provide a gas turbine engine which is capable of transiting between various speeds while maintaining an allowable clearance between its rotor and stator.
Another object of this invention is to provide a high speed gas turbine engine with high efficiency characteristics during both steady-state and transitional operation.
Yet another object of this invention is to provide a gas turbine engine capable of operating over a variable speed schedule without attendant interference between the rotor and stator.
These objects and other features and advantages become more readily apparent upon reference to the following description when taken in conjunction with the appended drawings.
SUMMARY OF THE INVENTION
Briefly, in accordance with one aspect of the invention, the shroud of a gas turbine engine is connected to and supported by a radially outwardly disposed shroud support structure which grows and shrinks in response to the temperature to which it is exposed. The temperature of the support structure is varied in a predetermined manner by its fluid communication with an air supply from the engine compressor. Because of the inherent characteristics of a gas turbine engine, the temperature of the gas supply will vary in proportion to the speed of the engine. Further, a thermally actuated valve interacts with the air supply and the support structure such that during periods of engine acceleration there is a free flow of air supply to the support structure, and during periods of deceleration the support structure is relatively isolated from the flow of the air supply. In this way, when the engine accelerates by the way of a throttle burst, a thermally actuated valve opens and allows the hot air to fully communicate with the support structure and thereby cause it to expand in the relatively quick manner. Subsequently, when the engine decelerates as by a throttle chop, the air supply temperature drops, the valve closes, and the support structure is relatively isolated therefrom so as to tend to remain at the higher temperature and thereby shrink at a slower rate than which it expanded. The relative growth between the stator and rotor structure is thereby reduced to a minimum during engine transitional periods.
By another aspect of the invention, the thermally actuated valve comprises a high thermal expansion cylinder which is exposed to the air supply and interacts with the support structure to open and close a radial gap therebetween in response to the air supply temperature change. One end of the cylinder is rigidly connected to a low thermal expansion material, and the other end thereof is free to expand and contract to define the valve gap. The growth of the cylinder free-end is then responsive to the air supply temperature but is accentuated by the fact that the other end is rigidly held so as to prevent growth thereof.
In the drawings as hereinafter described, the preferred embodiment is depicted; however, various other modifications and alternate constructions can be made thereto without departing from the true spirit and scope of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic representation of a jet engine in which the present invention in embodied; and
FIG. 2 is a partial sectional view of a turbine portion of the jet engine showing the particular details of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to FIG. 1, a turbofan engine 10 is shown to include a fan rotor 11 and a core engine rotor 12. The fan rotor 11 includes a plurality of fan blades 13 and 14 mounted for rotation on a disc 16. The fan rotor 11 also includes a low pressure or fan turbine 17, which drives the fan disc 16 in a well-known manner. The core engine rotor 12 includes a compressor 18 and a power or high pressure turbine 19 which drives the compressor 18. The core engine also includes a combustion system 21, which combines a fuel with the air flow and ignites the mixture to inject thermal energy into the system.
In operation, air enters the gas turbine engine 10 through an air inlet 22 provided by means of a suitable cowling or nacelle 23 which surrounds the fan rotor 11. Air entering the inlet 22 is compressed by means of the rotation of the fan blades 13 and 14 and thereafter is split between an annular passageway 24 defined by the nacelle 23 and an engine casing 26, and a core engine passageway 27 having its external boundary defined by the engine casing 26. The pressurized air which enters the core engine passageway 27 is further pressurized by means of the compressor 18 and is thereafter ignited along with high energy fuel in the combustion system 21. This highly energized gas stream then flows through the high pressure turbine 19 to drive the compressor 18 and thereafter through the fan turbine 17 to drive the fan rotor disc 16. The gas is then passed out the main nozzle 28 to provide propulsion forces to the engine in a manner well known in the art. Additional propulsive force is gained by the exhaust-pressurized air from the annular passage 24.
It should be noted that although the present description is limited to an aircraft gas turbine engine, the present invention may be applicable to any gas turbine engine power plant such as that used for marine and industrial applications. The description of the engine shown in FIG. 1 is thus merely illustrative of the type of engine to which the present invention is applicable.
Referring now to FIG. 2, the high pressure turbine portion of the engine is shown in greater detail and comprises a single-stage row of rotor blades or buckets 29 rotatably disposed in the flow path of the hot gases as shown by the arrows. The hot gases flow from the annular combustor inner casing 31 rearwardly to a row of circumferentially spaced high pressure nozzles 32, through the circumferentially spaced row of buckets 29, through a circumferentially spaced stationary row of low pressure nozzles 33 to finally impinge on the circumferentially spaced row of rotatable low pressure turbine blades or buckets 34 of the fan turbine 17 and finally to exhaust out the main nozzle 28. Circumscribing the row of high pressure buckets 29 in close clearance relationship therewith is an annular shroud 36 made of a suitable abradable material for closely surrounding the buckets 29 but allowing some frictional engagement and wear at particular operational moments wherein the clearance between the shroud and the blades may be temporarily lost. The shroud is preferably made of a number of annular sectors attached to the inner side of an annular band 37 by conventional means. The annular band 37 is preferably made up of a number of sectors forming a complete circle. The annular band 37 is in turn supported by an annular ring 38 having at its rearward end, a radially inwardly extending collar 39 which is attached to the annular band 37 by way of an annular bracket 41. The forward side of the annular band 37 is attached to the annular ring 38 by way of an L-shaped annular bracket 42 and a plurality of bolts 43. Support for the annular ring 38 is derived by connection to the low pressure nozzle support 44 by bolts 45 at the rear end thereof, and connection to the turbine casing 46 along with the high pressure nozzle support 47 by way of a plurality of bolts 48 spaced circumferentially around the casing.
As the turbine casing 46 extends rearwardly around the high pressure turbine portion of the engine, it is suddenly enlarged by the manifold portion 49 which forms an annular plenum 51 between the manifold and the annular ring 38. Fluidly communicating with the plenum 51 is a plurality of air bleed off conduits 50 which carry bleed off air from the intermediate stages of the compressor 18 for the purpose of turbine nozzle cooling in a manner well known in the art.
Referring now more specifically to the annular ring 38, a radially outwardly extending flange 52 is formed thereon to project outwardly into the plenum 51. Axially spaced in the rearward direction an L-shaped flange 53 also projects radially outward but not to the extent of the outer diameter of the flange 52. The ring 38 with its flanges 52 and 53 is composed of the material having a relatively low coefficient of thermal expansion. Rigidly attached to the flange 52 and projecting forwardly to the turbine casing 46 is a cylindrical structure 54 which surrounds a portion of the annular ring 38 to form a cavity 56 therebetween. A plurality of apertures 57 are formed around the circumference of the cylindrical structure 54 to provide fluid communication between the plenum 51 and the cavity 56. Fluid communication is further provided between the cavity 56 and the area 58 defined by the axially spaced flanges 52 and 53, by a plurality of axially extending holes 59 formed in the flange 52. To further define that area 58 between the two flanges 52 and 53, a cylinder 61 is rigidly attached to the flange 52 by a plurality of bolts 62, and extends axially rearwardly to surround the outer surface 63 of the flange 53. The cylinder 61 is composed of a material having a high thermal coefficient of expansion which reacts with the ring 38 and associated flanges to control the flow of bleed off air in the plenum 51 during transient and steady-state periods of engine operation to obtain the desired state of growth characteristics for the establishment of proper clearances between the shroud 36 and the turbine buckets 29.
At the rearward end of the manifold 49 an annular support structure 64 is attached to the manifold 49 by a plurality of bolts 65 and acts to support the second stage low pressure nozzle 33. The support structure 64 is connected to the stage one nozzle support 44, and together they partially define a secondary plenum 66 which is downstream of and supplied by cooling air from the plenum 51. A plurality of circumferentially spaced holes 67 provide fluid communication between the secondary plenum 66 and the nozzle cavities 68 for cooling of the nozzles in a manner well known in the art. Further defining the secondary plenum 66 is the annular oblique flange 69 connected to the manifold 49 by bolts 65 extending radially inwardly to surround the L-shaped flange 53 at a radially outward spaced position so as to trap one end of the cylinder 61 therebetween. The annular flange 69 and its mechanically connected parts are composed of a material with a relatively low thermal coefficient of expansion. The interaction of the cylinder 61 with the adjacent surfaces of the flange outer surface 63 and the annular oblique flange seat surface 70 acts as a temperature responsive valve which is closed when in the dotted line position and open when in the position shown in FIG. 2.
In a typical operation of an aircraft turbine engine, assume that the aircraft engine is in the idle position. The air entering the plenum 51 is relatively cool since it hasn't been compressed to any great degree, and the cylinder 61 is thus in a relatively contracted position as shown by the dotted lines in FIG. 2 to present a closed valve position. The flow of air from the plenum 51 through the apertures 57 to the annular slot 59 is thus virtually shut off and the air flow pattern tends to be as shown by the dotted line arrows from the plenum 51 to the secondary plenum 66. As the engine is accelerated, for example to maximum thrust position, the degree of compression of the air in the compressor 18 is increased, and the air being delivered to the plenum 51 is relatively hot. This hot air acts on the exposed cylinder 61 to cause it to quickly increase in size. Conversely, the angular ring 38 and its associated flanges 52 and 53 are very slow to respond to this temperature change and when responding they do not expand to the degree that the cylinder 61 expands. The result is that the cylinder unrestricted end expands to the position shown by the solid lines in FIG. 2, to open the valve. The air from the plenum 51 then passes through the apertures 57, the holes 59, into the space 58 and into the plenum 66 as shown by the solid arrows in FIG. 2. Since the air flows past the flanges 52 and 53 and over the ring 38, the hot gases tend to quickly heat up the combined structure and cause it to expand relatively fast to thereby increase the inner diameter of the supported shroud 36. When the speed of the engine is subsequently reduced, as by a throttle chop, the air being delivered to the plenum 51 is again relatively cool and the cylinder 61 quickly responds to the thermal change to shrink back to the dotted position of FIG. 2 and close the valve. The ring 38 and associated flanges 52 and 53 are thus virtually isolated with the hot gases and tend to cool very slowly to thereby bring the shroud 36 down to its shrunken condition at a very low rate. Assuming now that the throttle is again moved to the maximum thrust position (hot rotor burst), the cylinder 61 is again exposed to hot gases and the valve is opened to again cause the support structure to expand relatively fast to increase the size of the shroud enclosing area.
It will, of course, be understood that various other designs and configurations can be employed to achieve the objects of the present invention. For example, the thermal valve, which has been described in terms of the ring 38, cylinder 61 and flange 69, may comprise various other arrangements to bring about the regulation of the shroud support temperature. The "open" and "closed" positions of the valve may be interposed to route the thermal fluid in the desired direction and manner. The fluid may be derived from a location other than the compressor, and its temperature may bear a different relationship from that of being proportional to engine speed as described. Further, the shroud support structure as shown and described is merely illustrative of various structures which could be thermally regulated with respect to size in order to facilitate the desired transient and steady-state radial positions of the shroud. | A shroud closely surronding a high thermal inertia rotor is provided with a support structure having low thermal inertia characteristics. The support structure is selectively exposed to different temperature mediums during transient operation by way of a thermal actuated valve so as to cause a rapid growth thereof during periods of engine acceleration and a slow shrinkage thereof during periods of deceleration of the engine. In this manner the clearance relationship between the shroud and enclosed rotor is maintained at a minimum during periods of steady-state and transitional operation to thereby increase the efficiency of the combination. | 5 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a divisional of pending application Ser. No. 10/446,133, filed May 28, 2003, entitled “A System and Method for Filtering Electromagnetic and Visual Transmissions and for Minimizing Acoustic Transmissions.” That application claims priority from U.S. Provisional Patent Application No. 60/383,137, filed on May 28, 2002, entitled “A System and Methods for Filtering Electromagnetic, Visual, and Minimizing Acoustic Transmissions,” and U.S. Provisional Patent Application No. 60/388,197, filed on Jun. 13, 2002, entitled “A System and Methods for Filtering Electromagnetic, Visual, and Minimizing Acoustic Transmissions.”
FIELD OF THE INVENTION
The invention relates to a system and method for filtering electromagnetic and visual transmissions, and for minimizing acoustic transmissions for security purposes. More specifically, the invention provides a system and methods to prevent unauthorized data collection and information exchange from or within buildings (such as through windows, doorways, other fenestration, or openings) or otherwise prevent such unauthorized data collection and information exchange from, for example, computer monitors or screens, personal digital assistants, and local area networks.
BACKGROUND OF THE INVENTION
Discussion of Related Art
Electromagnetic radiation of various frequencies is radiated from many devices used in a wide range of facilities including homes, workplaces such as offices, manufacturing and military installations, ships, aircraft and other structures. Examples of such devices include computers, computer monitors, computer keyboards, radio equipment, communication devices, etc. If this radiation escapes from the facility, it can be intercepted and analyzed for the purpose of deciphering data associated with or encoded in the escaped radiation. For example, technology exists for reconstructing the image appearing on a computer monitor in a building from a remote location outside the building or from a location within a building by detecting certain wavelength frequencies from the monitor screen even if the monitor screen is not in view from the remote location. This is accomplished by known techniques wherein certain frequencies of light from the monitor screen, even after being reflected from various surfaces inside the building or room where the monitor is located, escape and are intercepted and analyzed by an eavesdropper in another location outside the building or room where the monitor is located. Obviously, the ability of an eavesdropper to intercept such radiation constitutes a significant security risk that is desirably eliminated from facilities where secrecy is essential.
Although walls, such as brick, masonry block or stone walls may effectively prevent the escape of light frequencies from a facility, radio frequencies pass through walls that are not properly grounded to prevent such passage. Moreover, windows or other openings allow the passage of radiation to the outside where it can be intercepted, and permit entry of various forms of radiation, such as laser beams, infrared, and radio frequencies, into the facility. As a result, sensitive or secret data may be gathered from within the structure.
Indeed, the United States Government has long been concerned by the fact that electronic equipment, such as computers, printers, and electronic typewriters, give off electronic emanations. The TEMPEST (an acronym for Transient Electromagnetic Pulse Emanation Standard) program was created to introduce standards that would reduce the chances of leakage of emanations from devices used to process, transmit, or store sensitive information. This is typically done by either designing the electronic equipment to reduce or eliminate transient emanations, or by shielding the equipment (or sometimes a room or entire building) with copper or other conductive materials. Both alternatives can be extremely expensive.
The elimination of windows and other openings from a structure would obviously minimize the above-noted security risk. The disadvantages of a windowless or enclosed structure, however, are self-evident. It would be highly desirable, therefore, to prevent the escape of radiation associated with data through windows, doorways, or other openings while allowing other radiation to pass therethrough so that the enjoyment of the visual effects provided by such openings can be obtained without an undue security risk.
In addition to the security risks associated with the passage of certain wavelengths of electromagnetic radiation, acoustic transmission through a window, door or other opening also poses a security risk. It would be of additional benefit if transmission of both acoustic and the aforementioned electromagnetic radiation through openings could be minimized or avoided while preserving the visual benefits provided thereby.
The need for reducing the undesirable effects of the sun—its heat, excessive energy usage, glare, and ultraviolet (UV) radiation—has led to the development of solar control window films. Solar control window films are thin polyester sheets that are mounted on the glass windows of buildings and automobiles via an adhesive. It is said that such films are effective in providing comfort, visibility, and increased energy efficiency.
In the current workplace or home environment, however, there is a need for more protection than solar control films can provide. For example, it is important to protect the work product of an individual, business, or other entity from unauthorized data collection through the glass windows or other openings of their offices. The conventional solar control films described above are, for the most part, incapable of rejecting the wide range of frequencies used for such unauthorized data and information exchange.
Given the importance of security in today's competitive marketplace, a system that could preserve the privacy of the workplace is very desirable. Such a system would provide both comfort and security that in turn can bring about many benefits, including increased productivity and the preservation of confidentiality in both the public and private sectors.
SUMMARY OF THE INVENTION
Accordingly, the present invention provides a system and method for filtering electromagnetic, visual, and minimizing acoustic transmissions by using a combination of filters that substantially obviates one or more of the problems due to the limitations and disadvantages of the related art. The invention further provides a system and methods whereby a combination of films has a shielding effectiveness that attenuates the transmission of radio frequency wavelengths there-through and preferably has a shielding effectiveness of 22 db-40 db in the frequency range of 30 megahertz-3 gigahertz; an IR transmission at wavelengths between 780 nm and 2500 nm of no more than 50%, and preferably of less than 20%, and more preferably of about 15%; and reduces the ability of anyone working in the ultraviolet (UV) through to the visible spectrum up to at least 450 nanometers, to penetrate a building or other surface by at least 99%.
To achieve these and other advantages and in accordance with the purpose of the present invention, as embodied and broadly described, the system and methods of the present invention include a combination of electromagnetic radiation filters, such as selective radiation absorbers and/or selective radiation reflectors. These may be part of a window. The system and methods according to the invention have, however, non-exclusionary applications; the invention can be interposed between glass surfaces or applied to every type of glazing. The system and methods according to the invention can also be used for free standing product application for computer screens, monitors and other stand-alone devices. Further, the system and methods according to the invention may be configured to form a separate covering that may be placed over computer screens, monitors and other stand-alone devices. The example of windows discussed herein is employed for convenience and is not intended to be limiting as to surface application.
The radiation filters of the combination may be individual or combined layers plied to a window in any sequence so that light that passes through the window, passes through the radiation filters used in the combination. The radiation filters may be applied on any surface of the glazing (i.e., glass or other transparent material used for windows) of the window to form a multilayered structure of the filters on the glazing. It is not essential for all the layers to be contiguous to each other on one surface of the glazing. Instead, the filters may be distributed in any manner over or in the glazing of a window so as to prevent the passage of the wavelengths that would pose a security risk if they were allowed to pass through the window. For example, one filter may be on one surface of a glass pane while the remaining filters may be distributed as a single or multilayer structure on another surface of the glass layer (e.g., glass pane) or the filters may be distributed on any of the surfaces of a plurality of glass layers of a window (e.g., a multi-glazed window structure such as a double or triple glazed window structure).
In addition, any or all of the filters may be used in conjunction with a conventional glass interlayer such as the glass interlayer used in conventional safety glass that comprises a plastic interlayer such as polyvinylbutyral (PVB) interposed between two glass layers. The filters may be incorporated in, deposited on, or laminated to or within the interlayer in that case the filters will be within the glazing of the window.
Each filter of the combination of filters is advantageously in the form of an individual layer or coating, but this is not essential. In the case of filters that are absorbers (filters that use a particular dye, metal, metal salt or pigment to absorb a desired wavelength or range of wavelengths), the entire combination of absorbers or a portion of the combination may be in the form of a mixture of dyes, metal, metal salt or pigments in a single layer as a coating or may be incorporated in a component of the window such as in the polyvinylbutyral interlayer used in safety glass or in an adhesive layer used to adhere film, sheets or the like to the glass. It is also possible to incorporate one or more of the absorbers as a mixture in a film or sheet attached to the window or as layers applied to or coated onto a film or sheet. The PVB layer or the adhesive layer may include electrically conductive particles therein in an amount to render the PVB or the adhesive conductive.
The film or sheet may be any of the films or sheets used to make conventional solar control films. An example of a film used for this purpose includes, polyethylene terephthalate (PET), but others may be used as well.
When a film or sheet is used in combination with glass, it is not essential for the entire combination of filters to be in or on the film or sheet. For example, one or more filters may be associated with the film or sheet as described above while any remaining filters may be connected to the glass as described above or vice versa. It is also possible to include a layer that comprises a mixture of absorbers with another layer that is a different filter to make the desired combination. For example, two absorbers such as dyes or pigments of the combination may be used as a mixture as two filters of the combination, and another filter of the combination may be in the form of a distinct layer or coating such as a metal reflecting or absorbing layer.
Moreover, it is not essential for the entire combination of filters to be distributed on the same surface. For example, one or more of the filters may be applied to the glazing of a window while remaining filters may be applied to computer screens or monitors, personal digital assistants, or other stand-alone devices.
It is also not essential for the combination of filters to be attached to a surface of a window, computer screen or monitor, personal digital assistant or other stand-alone device. For example, the combination of filters may be configured to form a separate covering that may be soft and pliable, such as a bag. In this embodiment the combination of filters may be advantageously attached to a clear or transparent flexible substrate (e.g., PET sheet or film) that may be configured into the shape of a bag. When configured as a separate covering such as a bag, the combination of filters may be placed over computer screens or monitors, personal digital assistants, or other stand-alone devices, may be easily used and removed, and preferably may be disposable. Alternatively, the combination of filters may be configured as a containment system, such as in the form of tent or sheet, thereby covering an entire workstation, including an outdoor or mobile workstation. As discussed above, it is not essential for the entire combination of filters to be configured to form the separate covering. For example, one or more of the filters may be in the form of all or part of a containment system, while remaining filters may be applied to computer screens or monitors, personal digital assistants, or other stand-alone devices. Thus, filters applied to a computer screen, monitor or other device can work in conjunction with the filters applied to the bag, tent or sheet to produce the desired effect.
Any coatings, layers, films, sheets, lamina or the like used in this invention may be applied to a component of the window (e.g., the glass or interlayer component) by techniques that are conventional and well known to those skilled in the art. For example, metal layers may be applied by conventional sputtering techniques or evaporative coatings techniques. Any of the various layers may be adhered to the glass by means of conventional adhesives.
Although glass is described herein as the typical material that is used to make a window, it is to be understood that other clear or transparent materials that are useful for making windows may be substituted for the glass. For example hard plastics such as polycarbonate, plexiglass, acrylic plastic, etc., may be used as a substitute for the glass.
In view of the above, it will be appreciated by one skilled in the art that the required combination of filters may be associated with the window in any manner or sequence providing they are configured to prevent passage of the critical wavelengths therethrough for achieving the above-described security feature. Optionally additional conventional components or layers may be applied to the window to improve the aesthetics and/or visual characteristics of the window or to provide additional solar control, anti-reflection or radiant heat exclusion or safety and security characteristics in accordance with known techniques.
The desired effect of the present invention (i.e., filtering the passage of certain wavelengths through the window) can be achieved with any type of light filter or light valve that prevents the passage of the selected wavelengths. Thus, for example, the light filters or light valves used in this invention may be any of the absorbers described above or any other type of light filter or light valve such as a wavelength selective reflective layer or any combination of different types of light filters and light valves. For example, light absorbers may be combined with reflective layers.
It will be appreciated that the filters used in this invention are selective with respect to the wavelengths being filtered and thus the glazing remains sufficiently transparent for use as a window. Sufficient transparency is achieved by allowing visible light transmission of at least 1%, although a higher visible light transmission of, at least, approximately 25-30% is preferred, with a transmission of 50%-70% being more preferred.
According to one embodiment, the invention uses a combination of filters comprising, in no particular order, a yellow film layer (including the type used to produce stage or drama lighting), a museum-grade film layer, and a tinted film layer (similar to, but not necessarily the same as, the type applied on automotive glass). To achieve the system of the present invention, the film layers may be combined in any order, and in any manner, including being overlaid or mixed.
The combinations of filters may be advantageously connected to a transparent substrate and are configured so as to exclude the passage of the selected wavelengths therethrough, such as by absorption and/or reflection of the selected wavelengths. Thus, uncoated or exposed areas that would permit the passage of the selected wavelengths should be avoided.
Although the filters are connected to the substrate, each filter does not have to be directly connected to the substrate. In other words, the connection of a filter layer may be made by connecting the filter layer to another filter layer that was previously connected to the substrate so that one filter layer is connected to the substrate via another filter layer. For example, when two filter layers are located on one side of the substrate, one filter layer is directly connected to the substrate while the other filter layer is connected to the substrate via the first filter layer (i.e., indirectly connected). The same applies in instances where more than two filter layers are connected to one side of the substrate. In other words, being connected to the substrate in this invention is intended to cover both direct and indirect connections. Also, when a filter is formed by mixing or impregnating absorbents such as dyes or pigments into a component, the filter comprised of dye and/or pigment is considered in the context of this invention as being connected to the component.
Instead of coating the filter as a layer on the substrate, the filter may be connected to the substrate by a lamination process wherein a previously formed filter layer is laminated onto the substrate either directly or indirectly.
The substrate may be the glazing of the window or may be a flexible transparent sheet (e.g., plastic sheets such as PET) that is then connected to the glazing. A portion of the combination of filters may be connected to the glazing and another portion of the combination of filters may be connected to one or more flexible transparent sheets that are connected to the glazing. Alternatively, the flexible transparent substrate with the combination of filters attached thereto may be configured as a bag to contain a computer screen or monitor, personal digital assistant or other stand-alone device placed therein. Preferably the bag is sealed or tightly closed with the computer screen or monitor, digital assistant or other stand alone device therein so that the wavelengths to be filtered will not escape from the bag. The flexible substrate with the combination of filters attached thereto may also be configured as a tent for temporary field applications so that personnel and the computer screen or monitor, etc., may be inside the tent. In use the tent should cover the personnel and equipment inside to prevent leakage of the wavelengths that are to be filtered.
All of the filters do not have to be applied to a single substrate. For example, in a multi-glazed window, the combination of filters may be distributed on one or more of the glass sheets of the glazing either as a coating or layer on the glass and on one or more sheets connected to the glass.
At least one of the filters may be advantageously electrically conductive to inhibit the passage of radio waves through the window.
The substrate may include other conventional solar control elements such as light absorbing layers, anti-reflecting layers, or reflectors thereon.
The system and method of the present invention may also be used as a Glass-fragmentation Safety Film and, as such, may be used to minimize flying glass fragments in real world situations. To accomplish this objective the flexible sheet may include one or more layers that inhibit glass fragments from becoming dangerous flying projectiles when the window breaks due to explosion, implosion, or due to force from a projectile. A suitable layer for this purpose is polyester film (e.g., PET) or other flexible clear film. For example a 7 mil thick PET film is adequate for this purpose. The PET film may be adhered to the film containing the combination of filters with an adhesive (e.g., a pressure sensitive adhesive such as an acrylic pressure sensitive adhesive or any of the other adhesives described herein). A suitable acrylic pressure sensitive adhesive includes Gelva 263 available from UCB Inc. that includes 8% by weight of benzophenone type UV absorber for light stability. The pressure sensitive adhesive may be coated at a rate of 4 lbs. per ream coat rate.
The film used to provide glass fragmentation protection should be located on the glass surface of a window that is in the interior of the building to prevent glass fragments from causing injury to occupants in the building.
The invention may also encompass a combination of filters that provides high visible light transmission and low electrical resistance (less than 4 ohms/square) for enhanced attenuation of electromagnetic interference (EMI) and enhanced attenuation of radio frequency interference (RFI) as well as effective filtering of UV and IR light. Some embodiments of the combination of filters provided by this invention are particularly useful for shields that are applied to plasma display screens and other display screens that emit large amounts of EMI/RFI, UV light or IR light. The shields provide the monitor with a security feature that is useful for preventing unauthorized surveillance of the display screen.
The invention also provides for the selection of various combinations of filters to customize the anti-surveillance security features to suit a particular need. This is because the combination of filters that affords the highest level of anti-surveillance security typically produces light transmission characteristics that are not esthetically pleasing when used on a window. In particular, some filters used in the invention produce a yellow color that is aesthetically unpleasing when applied to a window. Not everyone needs such a high level of security that would necessitate compromising visual aesthetics. For many applications, e.g., business and home use, it may be desirable to eliminate the yellow filter from the combination to improve visual aesthetics while still providing an acceptable level of security.
The invention also provides for the inclusion of color correcting layers in the combination of filters to correct the undesired yellow color associated with the yellow filter.
BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying drawings that are included to provide further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description, serve to explain the principles of the invention.
In the Drawings:
FIG. 1 is a graph depicting light transmission properties of a yellow filter used in embodiments of the present invention;
FIG. 2 is a graph that shows the light transmission properties (wavelengths from 300-400 nm) of a light filter that may be used in embodiments. invention;
FIG. 3 is a cross-sectional view of a combination of a three light filters configuration connected to a substrate in accordance with an embodiment of the present invention;
FIG. 4 is a cross-sectional view of a filtering configuration having two of the light filters layers depicted FIG. 3 connected to one side of the substrate and the remaining third filter of FIG. 3 is attached to the other side of the substrate in accordance with an embodiment of the present invention;
FIG. 5 is a cross-sectional view depicting a double glazed window formed in accordance with an embodiment of the present invention;
FIG. 6 is a cross-sectional view of a plurality of light filters attached to conventional safety glass in accordance with an embodiment of the present invention;
FIG. 7 is a cross-sectional view depicting a combination of light filters connected to a flexible transparent substrate in accordance with another embodiment of the present invention;
FIG. 8 is a cross-sectional view depicting multiple light filters connected to a transparent plastic sheet that, in turn, is adhered to a window glass in accordance with an embodiment of the present invention;
FIG. 9 is a cross-sectional view depicting the use of a sealant to cover any gaps between the edge of a flexible sheet of a filter of the present invention and a window frame, in accordance with an embodiment of the present invention;
FIGS. 10-16 are cross-sectional views in accordance with other particular embodiments of the present invention;
FIG. 17 is a cross-sectional view of a temporary release liner employed in embodiments of the present invention;
FIG. 18 is a cross-sectional view of a filter combination embedded within PVB layers that are interposed between multiple glass layers in accordance with an embodiment of the present invention;
FIG. 19 is a top view of the configuration depicted in FIG. 18 ;
FIG. 20 is a cross-sectional view of a filter combination having a glass-fragmentation safety shield layers in accordance with an embodiment of the present invention; and
FIG. 21 is a cross-sectional view of two distinct, separated combinations filter layers in accordance with an embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Reference will now be made in detail to embodiments of the present invention, examples of that are illustrated in the accompanying drawings.
In one embodiment, the system and methods include a combination film illustrated in FIG. 3 consisting of a first layer 1 that is a standard yellow film layer having the wavelength transmission properties shown in FIG. 1 formed on a substrate 4 such as glass or acrylic; a second layer 2 that is a film layer having the wavelength transmission properties of FIG. 2 formed on the first layer; and a third film layer 3 , having the electromagnetic filtering properties of the XIR-70 film shown in Table 1 below and an IR transmission at wavelengths between 780 nm and 2500 nm of no more than 50%, and preferably of less than 20%, and more preferably of about 15%, formed on the second layer. A film having the wavelength transmission properties shown in FIG. 1 is available from, for example, CPFilms as CPFilms Yellow Q2186 Film. An example of a film having the transmission properties of FIG. 2 is museum-grade film manufactured by FTI Sun-Gard. An example of the third layer is the XIR 70 Film manufactured by Southwall Technologies. XIR 70 film is a well-known component of a glass tint used in original equipment laminated automotive glass. Table 1 shows the characteristics of this type of tinted glass and, more particularly, Table 1 shows the properties of XIR 70 film that is an example of the third layer of the present invention.
TABLE 1
Visible
Relative
Unit
Light
Visible
Total Solar
Solar
Heat Gain
Product/
Thickness
Transmittance
Reflectance
Transmittance
Reflectance
Btu's/Hr/
Ultraviolet
Glass Type
Si
(Tvis) %
Exterior %
(Tsol) %
Exterior %
Ft 2
Blockage %
Clear Glass
4 mil
90
9
81
8
220
30
Standard
4 mil
81
8
56
6
171
55
Auto
Green Tint
Spectrally
4 mil
74
7
44
5
150
70
Absorbing
Green
XIR 70
5 mil
70
9
46
22
117
>99
XIR 75
5 mil
75
11
52
23
135
>99
Note:
XIR Glass construction is two plies of 2.1 mil clear glass with XIR-pvb interlayer.
Glass or a flexible transparent sheet having the first, second and third layers thereon, when used in the system and methods of the present invention is capable of at least 99% light rejection at up to at least 450 nanometers. In an alternative embodiment, the sequence of the first, second, and third film layers may be varied. Also, any of the film layers may be substituted by other films having similar transmission properties. In addition, the film layers may be overlaid or combined.
The first film layer noted above (e.g. the film having the properties shown in FIG. 1 ) absorbs selective wavelengths as illustrated in the graph, wherein the vertical axis on the right side of the FIG. 1 depicts the percent transmission while the vertical axis on the left side of the FIG. 1 depicts the corresponding decimal equivalent. The first film layer has the benefits of blocking or attenuating various types of electromagnetic energy. In particular, FIG. 1 illustrates how this particular yellow film filter has light transmission at wavelengths below 450 nm of less than 50%. In fact, the yellow film filter is substantially intransitive between 400 and 450 nm. Thus, the present invention employs a yellow film that prevents various types of known surveillance.
The second film layer (e.g., the film whose properties are shown in FIG. 2 ) exhibits an increasing percentage of light transmission beginning at about 380 nanometers as shown in FIG. 2 . In one embodiment, the second film layer exhibits light transmission percentages for various wavelengths as shown below in Table 2.
TABLE 2
Wavelength
Light Transmission
320 nm
0.1-0.3%
380 nm
0.4-0.5%
400 nm
3-5%
550 nm
85-88%
The film having the properties shown in FIG. 2 and in Table 2 may have a percent light transmission at 320 nm and 380 nm that is less than 1% of the transmission at 550 nm. In addition, the percent light transmission at 480 nm may be less than 50% of the transmission at 550 nm.
The third film layer (e.g., the film having similar properties to the XIR-70 film described in Table 1) has an IR transmission at wavelengths between 780 nm and 2500 nm of no more than 50%, preferably less than 20%, and more preferably about 15%. An example of the third film layer may be about 2 mils thick; have a visible light transmittance of about 60-70%; a visible reflectance (exterior) of about 9%; a total solar transmittance of about 46%; and a solar reflectance (exterior) of about 22%. The surface resistance of the exemplary XIR film used in this invention is in the neighborhood of 6.0 ohms/square.
The embodiment of the invention. that uses the first, second, and third film layers may produce a yellow cast due to the inclusion of the yellow film layer. This yellow cast is seen when looking from the inside toward the outside and is similar to the lighting in a shooting range or looking through night vision goggles. The exterior reflected color of the invention is not restricted, however, as a wide range of metallized products may be used in the mix to change the exterior appearance of the film. Testing has shown that different metallized versions of the invention can be made, and with the insertion of yellow, different colorations can be achieved.
As noted above, the light filters may be sequenced or distributed in any manner. FIG. 3 illustrates an embodiment wherein film layers 1 , 2 and 3 (that are light filters) are connected to one side of substrate 4 . FIG. 4 illustrates an alternative embodiment wherein film layers 1 and 2 are connected to one side of the substrate 4 while film layer 3 is connected to the other side of substrate 4 . In a further embodiment illustrated in FIG. 5 , the window glazing that serves as the substrate comprises two separate spaced-apart glass sheets 5 and 6 . Film layers 1 and 2 are attached to either side of glass sheet 5 while film layer 3 is attached to glass sheet 6 . Film layer 3 in FIG. 5 may be attached to either side of sheet 6 . In a further embodiment illustrated in FIG. 6 , the substrate upon that the films are connected may be a standard safety glass that includes PVB interlayer 7 interposed between glass sheets 5 and 6 . Film layers 3 and 2 are connected to glass sheet 5 and film layer 1 is connected to glass sheet 6 . It is also possible to connect any or all of film layers 1 , 2 and 3 to PVB interlayer 7 .
Another filter that may be used in the various combinations of filters in the present invention is a UV screening film. The UV screening film is advantageously a weatherable PET UV screening film, is preferably a PET film with UV absorbers dyed into it in an amount to produce at least 2.4 optical density (OD) absorbance. A suitable PET film includes the film manufactured by the dyeing process described in U.S. Pat. No. 6,221,112. One or more of the UV screening films may be used in the present invention. Also, instead of using a UV screening film, UV absorbers may be incorporated into another layer or on a component of window glazing.
The conventional museum grade film described-above for use in second generally comprises the combination of two layers of the aforementioned UV screening film. Thus, the museum grade film may be substituted for two UV screening films in the overall combination of filters.
As also noted above, the light filters may be distributed on more than one surface. For example, film layers 2 and 3 may be connected to a window while film layer 1 is connected to a computer screen or other stand-alone device. Alternatively, film layers 1 and 2 may be connected to a computer screen or other stand-alone device, while film layer 3 is connected to a window.
Moreover, it is not essential for the combination of filters to be attached to a surface. For example, film layers 1 , 2 , and/or 3 may be configured to form a separate covering that may be soft and pliable, such as a bag. In this embodiment, the combination of filters may be placed over computer screens or monitors, personal digital assistants, or other stand-alone devices, may be easily used and removed, and preferably may be disposable. It should be noted that the soft, pliable covering may be configured so that it includes only some of the filters, for example, filters 2 and 3 , while filter 1 is directly applied to the screen or monitor. Thus, the soft, pliable covering will work in conjunction with a filter applied to a stand-alone device. In an alternate embodiment, film layers 1 , 2 , and/or 3 may be configured as a containment system, such as in the form of a tent or sheet, thereby covering an entire workstation. It should be noted that the containment system may also be configured so that it includes only some of filters, for example, filters 2 and 3 , while filter 1 is directly applied to the screen or monitor. Thus, the containment system, like the soft, pliable covering described above, will work in conjunction with a filter applied to a stand-alone device. In a further embodiment, film layers 1 , 2 , and/or 3 may be configured to form part of a containment system, such as a window of the tent or sheet.
In an alternative embodiment, film layers 1 , 2 , and/or 3 may be substituted by corresponding filters that meet the minimum filtering criteria of film layers 1 , 2 , and/or 3 . One of the light filters of the combination may be a metal or a metal stack comprising an electrically conductive metal layer which is optionally interposed between two nickel/chrome alloy layers. The electrically conductive metal layer preferably has at least the electrical conductivity of aluminum or higher, and more preferably has at least the electrical conductivity of copper or higher. Most preferably the electrically conductive metal is copper. The nickel chrome alloy is utilized to provide corrosion protection for the electrically conductive metal and may be omitted if the anti-corrosion benefit is not desired. Other anti-corrosion metals or metal alloys such as stainless steel may be substituted for one or both the nickel/chrome alloy layers. It is also possible to provide the nickel/chrome alloy or an anti-corrosion metal or metal alloy on only one side of the electrically conductive metal layer, such as a Hastelloy alloy or an Inconel alloy that are well known to those skilled in the art. An example of a Hastelloy alloy includes Hastelloy C276 that has the characteristics shown in Table 3.
TABLE 3
Chemical composition, percent by weight:
C, 0.02 a , Mn, 1.00 a ; Fe, 5.50; S, 0.03 a ; Si, 0.05 a ; Cr, 15.50; Ni, balance;
Co, 2.50 a ; Mo, 16.00; W, 3.75; V, 0.35 a ; P, 0.03 a Maximum
Physical constants and thermal properties
Density, lb/in. 3 : 0.321
Coefficient of thermal expansion, (70-200° F.) in./in./° F. × 10 −6 : 6.2
Modus of elasticity, psi: tension, 29.8 × 10 6
Melting range, ° F.: 2,415-2,500 Specific heat, Btu/lb/° F., 70° F.: 0.102
Thermal conductivity, Btu/ft2/hr/in./° F., 70° F.: 69
Electrical resistivity, ohms/cmil/ft, 70° F.: 779
Heat Treatments
Solution heat treat 2,100° F., rapid quench.
TENSILE PROPERTIES
Solution Treated 2,100° F., Water Quench
Y.S., psi,
Elong., in
Hardness,
Temperature, ° F.
T.S., psi
0.2% offset
2 in. %
Brinell
70
113,500
52,000
70
—
400
101,700
44,100
71
—
600
95,100
39,100
71
—
800
93,800
33,500
75
—
1,000
89,600
31,700
74
—
1,200
86,900
32,900
73
—
1,400
80,700
30,900
78
—
1,600
63,500
29,900
92
—
1,800
39,000
27,000
127
—
Rupture Strength, 1,000 hr
Solution Treated, 2,100° F., Water Quench
Test
Strength,
Elong.,
Reduction
Temperature, ° F.
psi
in 2 in., %
of area, %
1,200
40,000
—
—
1,400
18,000
—
—
1,600
7,000
—
—
1,800
3,100
—
—
Impact Strength
Solution Treated, 2,100° F., Water Quench
Test temperature, ° F.
Type test
Strength, ft-lb
−320
Charpy-V-notched
181
+70
Charpy-V-notched
238
+392
Charpy-V-notched
239
An example of an Inconel alloy includes Inconel 600 that has the characteristics shown in Table 4.
TABLE 4
Chemical composition, percent by weight: C, 0.08; Mn, 0.5; Fe, 8.0;
S, 0.008; Si, 0.25; Cr, 15 Ni, 76.0 Cu, 0.25; Ti, 0.35;
A1, 0.25
Physical constants and thermal properties
Density, lb/in. 3 : 0.304
Coefficient of thermal expansion, (70-200° F.) in./in./° F. × 10 −6 : 7.4
Modulus of elasticity, psi: tension, 30 × 10 6 ; torsion, 11 × 10 6
Poisson's ratio: 0.29
Melting range, ° F.: 2,470-2,575
Specific heat, Btu/lb/° F., 70° F.: 0.106
Thermal conductivity, Btu/Ft 2 /hr/in./° F., 70° F.: 1
Electrical resistivity, ohms/cmil/ft, 70° F.: 620
Curie temperature, ° F.: annealed, −192
Permeability (70° F., 200 Oe): annealed, 1.010
Heat treatments used in annealed condition, 1,850° F./30 min.
Tensile Properties
Hot Rolled
Y.S., psi, 0.2%
Elong. in
Hardness,
Temperature, ° F.
T.S., psi
offset
2 in. %
Brinell
70
90,500
36,500
47
—
600
90,500
31,100
46
—
800
88,500
29,500
49
—
1,000
84,000
28,500
47
—
1,200
65,000
26,500
39
—
1,400
27,500
17,000
46
—
1,600
15,000
9,000
80
—
1,800
7,500
4,000
118
—
Rupture Strength, 1,000 hr
Solution Annealed, 2,050° F./2 hr
Test
Elong.,
Reduction
Temperature, ° F.
Strength, psi
in 2 in., %
of area, %
1,500
5,600
—
—
1,600
3,500
—
—
1,800
1,800
—
—
2,000
920
—
—
Creep Strength (Stress, psi, to Produce 1% Creep)
Solution Annealed 2,050° F./2 hr.
Test Temperature, ° F.
10,000 hr
100,000 hr
1,300
5,000
—
1,500
3,200
—
1,600
2,000
—
1,700
1,100
—
1,800
560
—
2,000
270
—
Fatigue Strength
Annealed
Test temperature, ° F.
Stress, psi
Cycles to failure
70
39,000
108
Test temperature, ° F.
Type test
Strength, ft-lb
+70
Charpy-V-notched
180
800
Charpy-V-notched
187
1,000
Charpy-V-notched
160
Another light filter that may be used in this invention includes a heat reflecting film. The heat reflecting film may be a sputtered metal/oxide stack described in U.S. Pat. No. 6,007,901 on a polyester (PET) film with UV absorbers dyed into it at 2.4 absorbance manufactured by the dyeing process described in U.S. Pat. No. 6,221,112. The disclosures of the aforementioned U.S. Pat. Nos. 6,007,901 and 6,221,112 are incorporated herein by reference. Alternatively any of the heat reflecting metal/oxide stacks described herein may be coated onto any component of window glazing to thereby eliminate the need of a plastic film. In other words the metal/oxide stack may be deposited onto any component of window glazing (e.g., coated directly or indirectly onto the glass of window glazing) without first coating the metal/oxide stack onto a film (e.g. polyester film) and then adhering the metal/oxide coated film onto the window glazing. The aforementioned metal stack in combination with the sputtered metal/oxide stack produces a light filter that has the required characteristics of the XIR-70 film, and may therefore be substituted for the XIR-70 film.
Any of the heat reflecting films that are well known to those skilled in the art may be also used in this invention. Such heat reflecting films generally comprise multiple stacks of discrete layers that are deposited onto a substrate such as a plastic film or glass. Each stack has in sequence a thin film of dielectric material (e.g., metal oxide) and a heat reflecting metal such as silver, gold, copper or alloys thereof. Substantially transparent metal compounds (e.g., metal oxides such as indium tin oxide) may be used as the dielectric.
The heat reflecting film may comprise in sequence: (a) a substantially transparent substrate; (b) a first outer dielectric layer; (c) an infrared reflecting metal layer; (d) a color correcting metal layer comprising a metal different from the infrared reflecting metal layer; (e) a protective metal layer comprising a metal different from the infrared reflecting metal layer and different from the color correcting layer; (f) one or more subcomposite layers each comprising: (i) a subcomposite inner dielectric layer; (ii) a subcomposite infrared reflecting metal layer; (iii) a subcomposite color correcting metal layer comprising a metal different from the subcomposite infrared reflecting metal layer; and (iv) a subcomposite protective metal layer comprising a metal different from the subcomposite infrared reflecting metal layer and different from the subcomposite color correcting layer; and (g) a second outer dielectric layer.
The dielectric layers are typically indium oxide, indium zinc oxide, indium tin oxide or mixtures thereof. However other metal oxides may be substituted for the above-mentioned oxides. Suitable oxides for use as the dielectric layer include metal oxides having an index of refraction in the range of 1.7-2.6. The thickness of the outside dielectric layers is typically between about 0.15 quarter wave optical thickness and about 1 quarter wave optical thickness.
The infrared reflecting metal layers are typically silver, gold, copper or alloys thereof and are laid down in a thickness of between 7 nm and about 25 nm. The color correcting metal layers preferably have a refractive index between about 0.6 and about 4 and an extinction coefficient for light in the visible range between about 1.5 and about 7. The color-correcting metal layers most preferably consist essentially of indium.
The protective metal layers are made from a metal whose oxide is substantially-optically non-absorbing, such as aluminum, titanium, zirconium, niobium, hafnium, tantalum, tungsten and alloys thereof. The protective metal layers typically have a thickness between about 1 nm and about 5 nm.
The heat reflecting film may also be a composite comprising in sequence: (a) a substantially transparent substrate; (b) a first outer dielectric layer; (c) an infrared reflecting metal layer; (d) a color correcting metal layer comprising a metal different from the infrared reflecting metal layer; (e) a protective metal layer comprising a metal different from the infrared reflecting metal layer and different from the color correcting layer; (f) a second outer dielectric layer; and (g) a substantially transparent top layer comprising a substantially transparent glass or polymeric material.
The heat reflecting film may also be a composite comprising in sequence: (a) a substantially transparent substrate; (b) a first outer dielectric layer chosen from the group of dielectric materials consisting of indium oxide, indium zinc oxide, indium tin oxide and mixtures thereof; (c) an infrared reflecting metal layer comprising an alloy of silver and copper; (d) a color correcting metal layer consisting essentially of indium; (e) a protective metal layer comprising a metal whose oxide has a heat of formation less than (more negative than) −100,000 cal/gm mole at 25 degree C. and (f) a second outer dielectric layer chosen from the group of dielectric materials consisting of indium oxide, indium zinc oxide, indium tin oxide and mixtures thereof.
Preferably the various layers of the heat reflecting film are assembled so as to transmit between about 40% and about 80% of light within the visible spectrum (preferably 40-60%). It is also preferable that the composites of the heat reflecting film have reflectances of visible light less than 15%, typically between about 5% and 15%. Finally, it is preferable that the layers of the heat reflecting film be so assembled so that the composite transmits and reflects visible light in “neutral colors” or “slightly bluish or greenish” transmission colors. Transmissions that are neutral in color are generally transmit visible light in equal intensities throughout the visible spectrum. Light transmitted with a slightly bluish or slightly greenish tint is light whose components with wavelengths in the 380-580 nm range are slightly higher in intensity than other wavelengths.
According to one embodiment the heat reflecting film comprises in sequence:
(a) a substantially transparent first substrate; (b) a first outer dielectric layer; (c) an infrared reflecting metal layer; (d) a color correcting metal layer comprising a metal different from the infrared reflecting metal layer; (e) a protective metal layer comprising a metal different from the infrared reflecting metal layer and different from the color, correcting layer; (f) a subcomposite comprising:
(i) a subcomposite inner dielectric layer; (ii) a subcomposite infrared reflecting metal layer; (iii) a subcomposite color correcting metal layer comprising a metal different from the subcomposite infrared reflecting metal layer; and (iv) a subcomposite protective metal layer comprising a metal different from the subcomposite infrared reflecting metal layer and different from the subcomposite color correcting layer;
(g) a second outer dielectric layer; and (h) a substantially transparent second substrate;
wherein the heat reflective filter transmits 40-80% of light within the visible wavelengths (preferably 60-70%) and has a reflectance of less than 15%; and wherein the color of both transmitted and reflected light from the heat reflecting fenestration product is either neutral or is slightly bluish or slightly greenish in color.
In another embodiment the heat reflecting composite comprises in sequence:
(a) substantially transparent first substrate; (b) a first outer dielectric layer; (c) an infrared reflecting metal layer comprising silver; (d) a color correcting metal layer comprising a metal chosen from the group of metals consisting of chromium, cobalt, nickel, zinc, palladium, indium, tin, antimony, platinum, bismuth and alloys thereof; (e) a protective metal layer comprising a metal chosen from the group of metals consisting of aluminum, titanium, zirconium, niobium, hafnium, tantalum, tungsten and alloys thereof; (f) a subcomposite comprising:
(i) a subcomposite inner dielectric layer; (ii) a subcomposite infrared reflecting metal layer comprising silver; (iii) a subcomposite color correcting metal layer comprising a metal chosen from the group of metals consisting of chromium, cobalt, nickel, zinc, palladium, indium, tin, antimony, platinum, bismuth and alloys thereof; (iv) a subcomposite protective metal layer comprising a metal chosen from the group of metals consisting of aluminum, titanium, zirconium, niobium, hafnium, tantalum, tungsten and alloys thereof;
(g) a second outer dielectric layer; and (h) a substantially transparent second substrate disposed contiguous with the second outer dielectric layer;
wherein the dielectric layers are chosen from the group of dielectric materials consisting of indium oxide, indium zinc oxide, indium tin oxide and mixtures thereof; wherein the heat reflective filter transmits 40-60% of light within the visible wavelengths and has a reflectance of less than 15%; wherein the color of both transmitted and reflected light from the heat reflect substrate is either neutral , or is blue or green in color; and wherein the composite transmits less than about 7% of the infrared energy in light having a wavelength greater than about 1500 nm.
In another embodiment the heat reflecting film is a composite comprising in sequence:
(a) a substantially transparent substrate; (b) a first outer dielectric layer; (c) an infrared reflecting metal layer; (d) a color correcting metal layer comprising a metal different from the infrared reflecting metal layer; (e) a protective metal layer comprising a metal different from the infrared reflecting metal layer and different from the color correcting layer; (f) a subcomposite comprising:
(i) a subcomposite, inner dielectric layer; (ii) a subcomposite infrared reflecting metal layer; (iii) a subcomposite color correcting metal layer comprising a metal different from the subcomposite infrared reflecting metal layer; and (iv) a subcomposite protective metal layer comprising a metal different from the subcomposite infrared reflecting metal layer and different from the subcomposite color correcting layer; and
(g) a second outer dielectric layer;
wherein the combined thickness T 1 of the infrared reflecting metal layer, the color correcting metal layer and the protecting metal layer is different than the combined thickness T 2 of the subcomposite infrared reflecting metal layer, the subcomposite color correcting metal layer and the subcomposite protecting metal layer, and wherein T 1 and T 2 are in a ratio to one another of about 1.2.
A preferred heat reflector film for use in this invention is made by sputter coating the following sequence of layers onto a PET film with UV absorbers dyed into it at 2.4 absorbance.
a first layer of indium tin oxide about 30 nm thick coated on said PET film, a first layer of silver/copper alloy about 9 nm thick (92.5 wt. % Ag and 7.5 wt. % Cu) coated on said first layer of indium tin oxide, a layer of indium metal about 3 nm thick coated on said first silver/copper alloy, a first layer of titanium metal about 1 nm thick coated on said indium, a layer of indium tin oxide about 80 nm thick coated on said titanium, a second 9 nm layer of silver/copper alloy (92.5 wt. % Ag and 7.5 wt. % Cu) coated on said indium tin oxide, a layer of indium metal about 2 nm thick coated on said second silver/copper alloy, a second layer of titanium metal about 1 nm thick coated on said 2 nm layer of indium, and a second layer of indium tin oxide about 30 nm thick coated on said second layer of titanium.
The layer of titanium functions as a protective sacrificial layer that prevents oxidation of the indium metal layer during the sputter coating of the indium tin oxide layer.
Alternatively the PET film may be eliminated and the above sequence of layers may be coated onto a component (e.g., glass) of window glazing.
The above described heat reflector has a sheet resistance that is less than 17 ohms/square.
As described above, some embodiments of the invention utilize the metal or metal stack which comprises an electrically conductive metal such as copper optionally interposed between the two nickel/chrome layers as well as the heat reflecting sputtered metal/oxide stack. Alternatively, one or more of the above-described filters may be replaced by a filter having the electromagnetic filtering properties of the XIR-70 film or the XIR-75 FILM described above in Table 1. In particular, the XIR-70 and XIR-75 films have an IR transmission at wavelengths between 780 nm and 2500 nm of no more than 50%, and preferably of less than 20%, and more preferably of about 15%. XIR-70 and XIR75 films are commercially available from Southwall Technologies. XIR-70 film and the XIR-75 films are well known components of glass tint used in original tinted glass and, more particularly, Table 1 shows the properties of XIR-70 film which may be used in the present invention as part of the overall combination of filters. An example of the XIR film may be about 2 mil thick; have a visible light transmittance of about 60-70%, a visible reflectance (exterior) of about 9%; a total solar transmittance of about 46%; and a solar reflectance (exterior) of about 22%. The surface resistance of an exemplary XIR film used in this invention is about 6.0 ohms/square.
Preferably the XIR-70 or XIR-75 film further includes an electrically conductive metal layer (e.g., copper or silver) to produce a sheet resistance which is less than 4 ohms/square.
In a preferred embodiment, improved anti-surveillance devices and system may be obtained by replacing the aforementioned metal stack (nickel chrome alloy/copper/nickel chrome alloy) and the heat reflecting metal/oxide stack with a high visible light transmission/low resistance (less than 4 ohms/square) filter in the combination of filters.
Most broadly, the high visible light transmission/low resistance (less than 4 ohms/square) filter is a stack that is either an IR reflecting metal layer sandwiched between two dielectric layers or a dielectric layer sandwiched between two IR reflecting metal layers. The above-noted stack is coated onto a component of window glazing or onto a transparent plastic sheet such as PET.
The dielectric of each of the dielectric layers in the aforementioned stack has an index of refraction in the range of about 1.35 to about 2.6. Preferably the dielectric is a metal oxide dielectric having an index of refraction in the range of about 1.7 to about 2.6.
The above-described high visible light transmission/low resistance (less than 4 ohms/square) filter is preferably a Ag/Ti or Ag/Au stack or other functionally equivalent stacks as described below.
The Ag/Ti stack may be a multilayered structure containing the following sequence of layers coated (preferably sputter coated) onto a component of window glazing or onto a transparent plastic sheet which is preferably polyethylene terephthalate (PET):
a layer of indium tin oxide which is preferably 30 nm thick; 2. a silver IR reflecting layer which is preferably about 9 nm thick; 3. a protective sacrificial layer of titanium about 1 nm thick; 4. a layer of indium tin oxide which is preferably about 70 nm thick; 5. a silver IR reflecting layer preferably about 9 nm thick; 6. a protective sacrificial layer of titanium preferably about 1 nm thick; 7. an indium tin oxide layer preferably about 70 nm thick; 8. a silver IR reflecting layer preferably about 9 nm thick; 9. a protective sacrificial layer of titanium, preferably about 1 nm thick; and 10. a layer of indium tin oxide preferably about 30 nm thick.
The indium tin oxide layers in the Ag/Ti stack has an index of refraction of about 2.0. The thickness of the silver layers may be adjusted to achieve the desired ohms per square for the above-described multilayered structure. The above-described multi-layered structure has a sheet resistance that is less than 4 ohms per square.
Preferably the Ag/Ti stack has a sheet resistance which is less than 2.5 ohms/square. An Ag/Ti stack having a sheet resistance less than 2.5 ohms/square is exemplified by a stack containing the following sequence of layers sputtered onto a component of window glazing or onto a transparent plastic sheet which is preferably PET:
1. a coating of indium tin oxide about 30 nm thick; 2. a silver IR reflecting layer which is about 11 nm thick; 3. a protective sacrificial layer of titanium about 1 nm thick; 4. a layer of indium tin oxide about 75 nm thick; 5. a silver IR reflecting layer which is about 13 nm thick; 6. a protective sacrificial layer of titanium about 1 nm thick; 7. an indium tin oxide layer about 70 nm thick; 8. a silver IR reflecting layer about 11 nm thick; 9. a protective sacrificial layer of titanium about 1 nm thick; and 10. a layer of indium tin oxide which is about 30 nm thick.
The Ag/Ti stack having the lower sheet resistance of less than 2.5 ohms per square provides lower electrical resistance, higher IR rejection at the 800 and above nm range with a visible light transmission of 70%. Using the Ag/Ti stack having a sheet resistance which is less than 2.5 ohms/square, results in a filter which is less dark, more conductive and which provides greater IR rejection compared to the filter containing the nickel-chrome alloy/copper/nickel-chrome alloy layered structure with the metal/oxide heat reflecting film.
The protective sacrificial layer of titanium will be oxidized to TiO 2 when the indium tin oxide layers are deposited to thereby prevent the indium tin oxide layer from oxidizing the silver.
The layers used in the Ag/Ti and Ag/Au stack may be sputter coated using any conventional sputter coating technique. For example the indium tin oxide layer in the Ag/Ti sputtered stack may be sputtered in an argon and oxygen environment and the metals in the Ag/Ti stack may be deposited in a pure argon environment.
The above described Ag/Ti stack has a visible light transmission (VLT) of about 65-69% T550 (i.e. percentage of VLT measured using light having a wavelength of 550 nm).
The Ag/Au stack is also a multilayered structure coated (preferably sputter coated) onto a component of window glazing or onto a clear plastic sheet such as PET and preferably contains the following sequence of layers:
1. A layer of indium tin oxide (ITO) preferably about 30 nm thick; 2. a silver IR reflecting layer preferably about 9 nm thick; 3. a layer of gold about 1 nm thick; 4. an ITO layer preferably about 70 nm thick; 5. a silver IR reflecting layer preferably about 9 nm thick; 6. a layer of gold preferably about 1 nm thick; 7. an ITO layer preferably about 70 nm thick; 8. a silver IR reflecting layer preferably about 9 nm thick; 9. a gold layer preferably about 1 nm thick; and 10. an ITO layer preferably about 30 nm thick.
The ITO layers in the above-described Ag/Au stack have a refractive index of about 2.0. The thickness of the silver layers may be varied to regulate the ohms per square for the above-described multilayered structure. The above-described multilayered structure has a sheet resistance that is less than 4 ohms per square.
The gold layers in the Ag/Au stack serve as a protective layer for the silver, but unlike the corresponding Ti layers in the Ag/Ti stack, the gold layers are not oxidized.
The ITO may be sputtered in an argon and oxygen environment while the metals may be deposited in a pure argon environment.
In both of the above described Ag/Ti and Ag/Au stacks, the first ITO layer is first sputter coated onto a component of window glazing or onto the clear plastic sheet and the remaining layers are sequentially sputter coated in the order indicated above.
In both of the above described Ag/Ti and Ag/Au stacks, any or all of the indium tin oxide layers may be substituted with any dielectric layer having an index of refraction in the range of about 1.35 to about 2.6, preferably a metal oxide dielectric having an index of refraction in the range of about 1.7 to about 2.6.
A third light filter that may be used in the present invention includes a 1.0 mil polyester (PET) film dyed yellow. This type of film is commercially available as Q2186 dark yellow. The film is manufactured by impregnating the polyester film with, for example, solvent dispersed yellow dye 54 or 64. The impregnation takes place utilizing 7 gms/liter loading. The film may be dyed using the process described in U.S. Pat. Nos. 3,943,105, 4,047,889, 4,055,971 or 4,115,054, the disclosures of that are incorporated herein by reference. The Q2186 dark yellow film is made with yellow dye 54 and may be the same as the film of first layer 1 shown in FIG. 3 . Instead of using a yellow-dyed film, the yellow dye may be used as a coating on a window or computer screen or on any substrate or other film or sheet used in this invention.
The above-described light filters used in this embodiment may be connected to a substrate polyester film to produce the transparent flexible sheet as illustrated in FIG. 7 .
Turning to FIG. 7 , this embodiment of the invention includes layers 9 - 19 and optionally includes release liner layer 8 that is removed prior to application to the glass of a window, or to a screen, monitor, or other stand-alone device.
Release liner 8 may be a 1 mil polyester (PET) film with a silicone release coating on it. Any suitable silicone release coating may be used, such as a tin catalyzed silicone release that has about 10 grams per inch release characteristic. Non-silicone release formulations may be substituted for the silicone release layer.
Layer 9 may be a conventional pressure sensitive adhesive that holds the flexible sheet of FIG. 7 to the glass. An example of a pressure sensitive adhesive includes an acrylic solvent-based pressure sensitive adhesive that is applied at about 10 lbs/ream coat weight. The pressure sensitive adhesive of layer 9 may include 4% by weight of a UV absorber such as a benzotriazole UV absorber. Such a pressure sensitive adhesive is commercially available as National Starch 80-1057. Other adhesives or adhesive types may be substituted for the PSA adhesive as can other types of UV absorbers. It should be appreciated by one of ordinary skill in the art that these UV absorbers function as stabilizers, and may be added to the present invention to protect the adhesive from deterioration (e.g., deterioration caused by sunlight). These stabilizers, however, are not required to practice the invention.
Layer 10 may be a 0.5 mil clear weatherable film. An example of layer 10 includes a polyester (PET) film with UV absorbers dyed into it in sufficient amounts to produce at 2.4 optical density absorbance. A suitable polyester film for layer 10 includes the film manufactured by the dyeing process described in above-cited U.S. Pat. No. 6,221,112. Other films with similar UV screening capability may be substituted for the above-described film used in layer 10 .
Layer 11 may be a laminating adhesive that is used to laminate the layers together. A useful laminating adhesive includes any conventional polyester adhesive with an isocyanate cross-linker added thereto. An example of such a laminating adhesive is Rohm and Haas's Adcote 76R36 adhesive with catalyst 9H1H. The adhesive may be applied at 1-1.5 lbs/ream coat weight. Other laminating adhesives may be substituted for the above-noted polyester type adhesive.
Layer 12 may be a 1.0 mil polyester (PET) film with sputtered heat reflecting, conductive metal stack coating made up of a copper layer interposed between two anti-corrosive nickel/chrome alloy layers. Layer 12 has a visible light transmission of about 35%. The nickel/chrome alloy layers may include Hastelloy. C276 or Inconel 600. Specific examples of Hastelloy C276 and Inconel 600 are described below.
Hastelloy C276 having the following mechanical properties: UTI tensil psi: 106,000; yield psi: 43,000; elong. % 71.0; and having the following chemical analysis:
Hastelloy C 276
Element
% by weight
C
.004
Fe
5.31
Mo
15.42
Mn
0.48
Co
1.70
Cr
15.40
Si
.02
S
.004
P
.005
W
3.39
V
0.16
Ni
Balance
Inconel 600 having the following mechanical properties: UTI tensil psi: 139,500; yield psi 60,900; elong. % 44.0; hardness: Rb85; and having the following chemical analysis:
INCONEL 600
element
% by weight
C
.08
Fe
8.38
Ti
0.25
Mn
0.21
Cu
0.20
Co
0.05
Cr
15.71
Si
0.30
S
<.001
Al
0.28
P
0.01
Ni
74.45
Nb + Ta
0.08
Layer 13 may be a laminating adhesive. The amount and type of laminating adhesive of layer 13 may be the same as the amount and type of laminating adhesive used in layer 11 .
Layer 14 may be a heat reflecting film. The heat reflecting film of layer 14 may include a sputtered metal/oxide stack (described in U.S. Pat. No. 6,007,901) on a 1.0 mil clear, weatherable polyester (PET) film. The polyester film has UV absorbers dyed into it in sufficient amounts to produce at 2.4 optical density absorbance. The film may be dyed using the dyeing process described in U.S. Pat. No. 6,221,112. Other films with UV screening capability may be used in place of the aforementioned UV screening film.
Layer 15 may be a laminating adhesive and may be the same as layers 11 and 13 .
Layer 16 may be a 1.0 mil polyester (PET) film dyed yellow. An example of this film is known commercially as Q2186 dark yellow film. It is made by impregnating the polyester film with solvent dispersed yellow dye 54 or 64 at 7 grams/liter loading. The dyed polyester film is made by the procedures prescribed in U.S. Pat. Nos. 3,943,105; 4,047,889; 4,055,971 or 4,115,054.
Layer 17 may be a pressure sensitive adhesive. A suitable acrylic pressure sensitive adhesive includes Solutia's Gelva 263 that includes 8% by weight of a benzophenone type UV absorber. The pressure sensitive adhesive is coated at a rate of 4 lbs/ream coat weight.
Layer 18 may include a 7 mil polyester film that is utilized to provide a safety characteristic so that sharp glass fragments do not become dangerous projectiles when the glass breaks. Other thicknesses and/or types of films could be used.
Lastly, layer 19 may be a conventional hardcoat layer that is approximately 1.0-2.0 microns thick. A suitable hardcoat composition may include the hardcoat described in U.S. Pat. No. 4,557,980; the disclosure of that is incorporated herein by reference.
The museum-grade film that may be utilized as one of the filters of this invention includes a combination of filters comprising the dyed polyester film of layer 14 and the dyed polyester film of layer 10 . Thus, the combination of these two dyed films used in the embodiments shown in FIGS. 7 and 8 is a functional equivalent of the museum-grade film, and may be used as a substitute therefor.
The above-described film illustrated in FIG. 7 has numerous properties including UV, visible, IR, EMI and RFI shielding capability and has a safety characteristic that prevents flying glass injuries due to layer 18 .
Turning to FIG. 8 , this embodiment of the invention results from removing release liner 8 from the flexible sheet illustrated in FIG. 7 , thereby allowing the remaining layers 9 - 19 to be attached to the glass or other surface of a window or to a screen, monitor or other stand-alone device. FIG. 8 includes glass substrate 20 connected to the sheet illustrated in FIG. 7 . When the present invention is applied to a window, the sheet of FIG. 7 may be adhered to the surface of the glass portion of the window that faces the inside of the room so that layer 18 can provide the desired safety feature described above. The side of the glass that faces the interior of the room is the side of the glass opposite to the side that receives sunlight from the direction shown by arrow 21 in FIG. 8 .
The combination of light filters used in this invention has a shielding effectiveness of 22 db-40 db in the frequency range of 30 megahertz to 3 gigahertz, an IR transmission at wavelengths between 780 nm and 2500 nm of no more than 50%, preferably less than 20%, more preferably about 15%, and a light transmission that is less than 1%, and preferably less than 0.1%, for wavelengths of 450 nm and less. In one embodiment, the combination of light filters has the properties shown in Table 5.
TABLE 5
Shielding Effectiveness in the frequency
22 db-40 db
range of 30 megahertz-3 gigahertz
Light transmission @ 450 nm
<1%
IR transmission
<50%
Emittance
0.81
% Solar Transmittance
13
% Solar Absorption
59
% Visible Transmittance
25
% Reflectance
22
% UV Transmittance
0.01
Solar Heat Gain Co-efficient
0.30
U Factor
1.09
Shading Coefficient
0.34
% Solar Energy Rejected
70
It should be apparent to one of ordinary skill in the art, however that the properties shown in Table 5 may vary according to the filter layers employed, although shielding effectiveness, IR transmission, and light transmission properties should preferably remain constant.
In a further embodiment of the present invention, the combination of light filters has the properties shown in Table 6.
TABLE 6
UV-transmission @ 380 nm
<0.1%
UV-Vis transmission from 380 to 450 nm
<2%
Visible transmission from 450-470 nm
<5%
Visible transmission from 470-780 nm
>1%
Near IR transmission at 900 nm
<10%
Near IR transmission at 1060 nm
<5%
Near IR transmission at 780 nm-1100 nm
<20%
Near IR transmission at 1150 nm
<5%
Near IR transmission at 1300 nm
<3%
Near IR transmission at 1550 nm
<2%
IR transmission at 1100-2500 nm
<5%
Conductivity
<7 ohms
per square
Shielding effectiveness for 30 megahertz-3 gigahertz
22 db-40 db
A flexible transparent sheet made in accordance with this invention may also be used to minimize acoustic transmissions from a building by carefully applying the film to the window with an adhesive while making certain that no visible air bubbles are formed between the flexible sheet and the glazing of the window. The term “visible air bubbles” used herein means air bubbles that are visible without any magnification (i.e., visible to the naked eye). It has been discovered that when the transparent flexible sheet lies over an air bubble, the flexible sheet behaves like the diaphragm of a loudspeaker. This causes unwanted transmission of sound waves. Avoiding these bubbles minimizes the transmission of the sound waves through the window.
The combination of filters used in this invention should cover the surface area of the entire window glazing or otherwise should be configured to minimize the passage of the selected wavelengths therethrough unless the combination of filters is being used as a bag or tent. Thus, when the filters are applied to the glazing by adhering a flexible transparent sheet thereto, the flexible transparent sheet having the light filters thereon should be carefully positioned so that there are no gaps or unprotected areas on the glazing. In an embodiment, a single transparent flexible sheet having the filters thereon is employed to avoid seams between the edges of the flexible sheets on the glazing of a window. The avoidance of seams is beneficial because seams allow leakage of the wavelengths that the present invention seeks to avoid. This leakage through the seams occurs even when the edges of the flexible sheets are butted against one another and even when the edges overlap one another.
There is also a potential for leakage of the wavelengths around the periphery of the flexible sheet adjacent to the window frame. Turning to FIG. 9 , leakage around the periphery may be minimized by applying an opaque electrically conductive sealant 22 around the periphery so that any gap 23 between the sheet 24 and the window frame 25 may be masked by the sealant. Thus, the sealant would cover any exposed portions of the glazing not covered by the sheet. FIG. 9 illustrates sheet 24 adhered to glazing 26 of a standard window. The sealant may be neutral curing to avoid unwanted chemical interaction with the sheet. An example of suitable sealant includes a silicone elastomer, such as Dow Corning 995 Silicone Structural Adhesive.
Preferably the flexible sheet is sized to avoid all gaps between sheet 24 and window frame 25 . However it is not humanly possible to avoid all gaps between sheet 24 and window frame 25 due to small irregularities on the edges of sheet 24 and window frame 25 . Thus sheet 24 should be sized so that the entire periphery of sheet 24 is in substantial contact with window frame 25 . Substantial contact, as used herein, means as much contact as is humanly possible given the small irregularities on the edges of sheet 24 and window frame 25 .
Another filter which may be used in the combination of filters is an IR absorbing filter which is a layer comprising an IR absorbing substance such as a layer of (lanthanum hexaboride) or other IR absorbing material such as antimony tin oxide. A preferred IR absorbing filter contains a combination of LaB 6 and antimony tin oxide. The IR absorbing material is preferably in the form of nanoparticles incorporated into a coating material such as adhesive or hardcoat material. Nanoparticles are particles having an average particle diameter of 200 nm or less, preferably less than 100 nm
Examples of suitable IR absorbing filters include the IR absorbing filters described in United States published patent application no. US 2002/0090507 A1 and WO 02/41041 A2, the specifications of which are incorporated herein by reference.
The IR absorbing filters described in WO 02/41041 A2 and US 2002/0090507 A1 are optically active film composites which include a layer of resin binder having a thickness of less than 6 microns and a pencil hardness of at least 2H, preferably 3H, and include nanoparticles of at least one metallic compound absorbing light having a wavelength in the range of 1000-2500 nm and nanoparticles of a second metallic compound which is an inorganic compound and which absorbs light having a wavelength in the range of 700-1100 nm. Preferably the composite has a visible light transmission of at least 50% and a percent TSER of at least 35%, and more preferably has a visible light transmission of at least 70%. For a composite having a visible light transmission in the range of 50-60% the percent TSER may be between 50-65%.
Pencil hardness is measured according to ASTM D3363-92a.
Visible light transmission is calculated using CIE Standard Observer (CIE 1924 1931) and D65 Daylight.
The percent TSER is the percentage total solar energy rejection which is calculated from optical and heat rejection properties of coated film measured on a Varian Analytical Cary 5 Spectrophotometer in accordance with ASTM E903-82, the absorption and transmission data being analyzed using parameters described by Perry Moon in the Journal of the Franklin Institute , Volume 230, pp. 583-618 (1940).
Preferably one metallic compound is antimony tin oxide (ATO), indium tin oxide (ITO), or tin oxide. Preferably, this metallic compound is ATO, and the layer contains 30-60% by weight of ATO, preferably 50-60% by weight of ATO.
The second compound may be modified ITO as described in U.S. Pat. No. 5,807,511 and/or at least one of a metal hexaboride taken from the lanthanum series of the Periodic Table. The preferred hexaborides are La, Ce, Pr, Nd, Gb, Sm, and Eu with La being the most preferred option. The layer contains a maximum of 3% by weight of the second metallic compound, preferably less than 2% and more preferably between 0.5-2%.
The binder may be a thermoplastic resin such as an acrylic resin, a thermosetting resin such as an epoxy resin, an electron beam curing resin, or preferably a UV curable resin which may be an acrylate resin of the type disclosed in U.S. Pat. No. 4,557,980, or preferably a urethane acrylate resin.
The layer of resin binder may be coated to a transparent polymeric film substrate, preferably a polyester film which is more preferably PET film. The infrared blocking layer forms a hardcoat for the film substrate which is particularly advantageous and may cut out a further processing step during composite film manufacture. The PET film may be coated with an adhesive for fixing the film composite to the substrate used in this invention. The PET film and/or adhesive may include at least one UV radiation absorbing material to block out substantially all UV radiation to less than 1% weighted UV transmission. Weighted UV transmission is derived from measurements made in accordance with ASTM E-424 and as modified by the Association of Industrial Metallisers, Coaters & Laminators (AIMCAL). The above-mentioned IR absorption filter composites have low visible reflectivity of less than 10% and have excellent weatherability with no loss of absorption properties and holding color, after 1500 hours in a Weatherometer.
The IR absorbing filter may include a transparent substrate coated with a layer of resin having a thickness of less than 6 microns and which contains nanoparticles of ATO and nanoparticles of a second metallic compound which is an inorganic compound which absorbs light having a wavelength in the range of 700-1100 nm and a second transparent substrate located on the layer of resin so that the layer of resin is sandwiched between the two substrates.
In one implementation of the present invention, a combination of filters comprises the above-described low resistant sputtered stack (either the Ag/Ti or the Ag/Au stack or the stacks having the sequence: dielectric layer/IR reflecting metal layer/dielectric layer or the sequence: IR reflecting metal layer/dielectric layer/IR reflecting metal layer) in combination with one or two UV screening films, as depicted in FIG. 10 .
Turning to FIG. 10 , the embodiment of the invention includes layers 27 - 32 . Layer 27 is an adhesive for adhesively securing the multilayered structure to glazing of a window or to the display screen of a plasma monitor or other type of display screen.
Layer 28 is a UV screening film.
Layer 29 is either the Ag/Ti or the Ag/Au low resistance (less than 4 ohms/square) sputtered stack as described herein.
Layer 30 is a laminating adhesive.
Layer 31 is either a clear film or a UV screening film.
Layer 32 is an optional hardcoat layer.
The above-described combination offers high visible light transmission and high EMI/RFI shielding attenuation. Thus the first combination may be applied to glazing of a window using adhesive layer 27 or may be adhered to the display screen of a plasma monitor or other display screen that emits large amounts of EMI/RFI, UV or IR.
The embodiment shown in FIG. 10 may be assembled using conventional film making, coating and laminating procedures. For example, Ag/Ti stack of layer 29 is formed on film 28 by conventional sputtering and hardcoat layer 32 is applied onto layer 31 using conventional hardcoating techniques either before or after lamination of the remaining layers. The entire multilayered structure is assembled into a laminate using conventional laminating adhesives and adhesive layer 27 is applied using conventional adhesive coating technology.
Another potentially advantageous combination of filters comprises the above-described Ag/Ti or the Ag/Au low resistance sputtered stack or the stacks having the sequence of dielectric layer/IR reflecting metal layer/dielectric layer or the sequence of IR reflecting metal layer/dielectric layer/IR reflecting metal layer, the above-described IR absorbing layer which preferably comprises LaB 6 and antimony tin oxide, and one or two UV screening films. An example of the second combination is illustrated in FIG. 11 .
Turning to FIG. 11 , this embodiment of the invention includes layers 27 - 33 . Layers 27 - 32 may be the same material as layers 27 - 32 of FIG. 10 . Layer 33 in FIG. 11 is the aforementioned IR absorbing layer which preferably comprises LaB 6 and antimony tin oxide.
The combination of filters exemplified in FIG. 11 provides IR rejection at the near IR wavelength range due to the incorporation of layer 33 therein. In addition, the second combination provides high EMI/RFI shielding attenuation and provides standard and high UV rejection. Standard UV rejection is provided by the embodiments of FIGS. 10 and 11 wherein layer 31 is a clear film. Higher UV rejection is obtained when layer 31 is the UV screening film in the embodiment shown in FIGS. 10 and 11 .
The example illustrated by FIG. 11 may be adhered to window glazing or to a plasma display screen or other type of display screen that emits large amounts of EMI/RFI or that emits large amounts of UV or IR light.
The embodiment shown in FIG. 11 may be assembled using the same conventional film making, coating and laminating procedures as described for the embodiment of FIG. 10 but which further includes coating a layer of IR absorbing material (e.g., a layer comprising LaB 6 and antimony tin oxide) onto film 31 .
A third possible combination of filters utilized in this invention comprises the previously described sputtered metal or metal stack (electrically conductive metal such as copper optionally sandwiched between two corrosion protection layers), one or more of the UV screening material of layer 28 as described above, and any of the yellow films described herein, especially the Q2186 yellow film. The third combination of filters is exemplified in FIG. 12 that includes layers 27 - 34 . Layers 27 , 28 , 29 , 30 , 32 and 33 may be the same material as the corresponding numbered layers in FIG. 11 .
Layer 31 in FIGS. 10 and 11 comprises a clear film or a UV screening film. Layer 31 in the example illustrated by FIG. 12 is the UV screening film so that there are two UV screening films in the combination exemplified by FIG. 12 (layers 28 and 31 ).
The combination shown in FIG. 12 further includes a yellow filter layer 34 , preferably the yellow film Q2186 as described herein.
The third combination of filters illustrated in FIG. 12 offers high visible light transmission and IR rejection at the near IR wavelengths due to the presence of layer 33 . In addition this embodiment provides enhanced EMI/RFI shielding attenuation and high UV rejection due to the combination of filters contained therein. The third combination may be applied to the glazing of a window as described herein.
A fourth combination of filters utilizes the combination of filters illustrated in FIG. 7 and further includes a color correcting layer as described herein. An example of the fourth combination is illustrated in FIG. 13 that includes layers 27 , 28 , 36 , 30 , 37 , 30 , 31 , 30 , 34 , 30 , 35 and 32 . Each of layers 30 shown in FIG. 13 is the laminating adhesive of layer 30 shown in FIGS. 10-12 . Layers 27 , 28 , 32 and 34 are the same material as the corresponding numbered layers in FIGS. 10-12 . Layer 36 is the same material as layer 12 in FIG. 7 and layer 37 is the same material as layer 14 in FIG. 7 .
In particular, the yellow cast associated with the various embodiments of the invention that include a yellow film layer can be altered to produce a more aesthetically pleasing color by the incorporation of a color correcting layer in the combination of filters. Any gray or dark gray colored film can be used to counteract the yellow color (although other colors may be used as well). For example, a gray or dark gray reflective stack having an overall visible light transmission of about 10% is suitable for this purpose. An example of such a stack comprises an aluminized PET film (PET sputter coated with Al) interposed between two layers of gray film (e.g., PET film treated with dye or dyes to produce a gray color). The aluminized PET desirably has a 45% visible light transmission and each of the dyed films desirably have a visible light transmission of about 35% to yield an overall visible light transmission of about 10%. The aluminized PET and the two dyed films are laminated together to form a sandwich structure with the aluminized PET film interposed between the two dyed film layers.
As noted above, layer 31 in the first combination may be a clear film or a UV screening film. Layer 31 in FIG. 13 is desirably the clear film.
Layer 35 in FIG. 13 is the color-correcting layer described herein. Preferably the color correcting layer of layer 35 is the structure described herein that contains the aluminized PET sandwiched between two gray dyed films.
A fifth combination of filters comprises the AgM or the Ag/Au low resistance sputtered stack, the LaB 6 IR absorbing layer, the yellow film such as yellow film Q2186, and an optional UV. screening film. In addition to the above combination of filters, the fifth combination further includes the above-described color-correcting layer. An example of the fifth combination of filters is illustrated in FIG. 14 that includes layers 27 , 28 , 29 , 30 , 31 , 30 , 33 , 34 , 30 , 35 and 32 . Layers 27 , 28 , 29 , 30 , 33 , 31 and 32 may be the same material as the corresponding numbered layers in FIGS. 10 and 11 . Layer 35 in FIG. 14 is the color-correcting layer that is the same as layer 35 in FIG. 13 . Layer 34 in FIG. 14 is the yellow film Q2186 of layer 34 in FIGS. 12 and 13 .
The fifth combination depicted in FIG. 14 offers high visible light transmission, IR rejection at the near IR wavelengths due to the combination of filters, particularly the filter of layer 33 . In addition, the fifth combination provides enhanced EMI/RFI shielding attenuation and provides very high UV and visual light rejection. The fifth combination may be applied to the glazing of a window as described herein or may be applied to the screen of a computer monitor particularly a plasma display screen of a monitor.
A sixth combination of filters omits the yellow film to avoid the aesthetically unpleasant lighting conditions produced when the yellow film is included in the combination of filters. By omitting the yellow film, a lower level of anti-surveillance security is achieved but the level is nonetheless effective for most applications, particularly business and home use applications. The embodiment that avoids the yellow film does not have to resort to using the color control layer that significantly reduces the transmission of visible light there through. The combination of filters employed in the sixth combination of filters comprises the sputtered stack of layer 36 used in the fourth combination of filters, the heat reflecting sputtered stack used in layer 37 of the fourth combination of filters and the UV screening material of layer 28 used in the example illustrated in FIG. 10 .
The sixth combination of filters is exemplified in FIG. 15 that includes the sequence of layers 27 , 28 , 30 , 36 , 30 , 37 , 30 , 31 and 32 that are the same material as the corresponding numbered layers in the embodiments illustrated in FIGS. 10-14 . The sixth combination of filters such as the combination of filters illustrated in FIG. 15 may be applied to the glazing of a window or may be applied to the display screen of a computer monitor.
The embodiment shown in FIG. 15 may be assembled using the same conventional techniques described above. In particular, layer 36 is made by sputter coating the metal stack (copper layer interposed between two nickel/chrome alloy layers) onto a transparent plastic film such as a 1 mil PET film. Layer 37 is formed by sputter coating the metal-oxide stack onto a 1 mil clear weatherable PET film with UV absorbers dyed into it to produce at least 2.4 optical density absorbance. Layers 36 and 37 along with films 28 and 31 are laminated together using the laminating adhesive layers 30 , and adhesive layer 27 is applied using conventional adhesive coating technology. Optional hardcoat layer 32 may be applied to film 31 using conventional hardcoat coating techniques either before or after lamination of the remaining layers.
A seventh combination of filters comprises the yellow film Q2186 and two UV screening films. An example of the seventh combination is illustrated in FIG. 16 and includes the sequence of layers 27 , 28 , 30 , 28 , 30 , 34 and 32 . Each of the layers utilized in the seventh combination of filters is the same material as the corresponding numbered layers in FIGS. 10-15 .
The seventh combination of filters, such as the example illustrated in FIG. 16 , may be applied to window glazing or may be applied directly to the screen of a computer monitor to prevent eavesdropping in the ultraviolet and visible light wavelengths. This combination of filters and other combinations that are applied to the screen of a computer may be adhesively secured to the monitor or may be mechanically secured.
Each of the embodiments of the invention illustrated in FIGS. 10-16 advantageously includes a temporary release liner that covers an exposed surface of adhesive layer 27 .
FIG. 17 illustrates the location of release liner 38 secured to adhesive layer 27 . Reference numeral 39 in FIG. 17 represents the various layers located below adhesive layer 27 in the embodiments shown in FIGS. 10-16 . Removal of release liner 38 allows the combination of filters to be adhesively secured to a desired substrate such as the glazing of a window or the screen of a computer monitor.
The release liner 38 used in the various embodiments of this invention may be any conventional release liner known to those skilled in the art. For example, the release liner may be a 1 mil PET film with a silicone release coating thereon. Any suitable silicone release coating may be used, such as a tin catalyzed silicone release that has about 10 grams per inch release characteristic. Non-silicone release formulations may be substituted for the silicone release layer.
The adhesive layer 27 used in the various embodiments of this invention may be any adhesive known to those skilled in the art for attaching a plastic sheet to glass. Pressure sensitive adhesives are particularly suitable for this purpose. Alternatively, a non-pressure sensitive adhesive may be used, and this non-pressure sensitive adhesive is advantageously a dear distortion free adhesive such as a functional polyester-based adhesive having siloxane functionality that provides a strong bond to glass. The adhesive layer 27 may comprise the same material used for layer 9 as described for the embodiment illustrated in FIG. 7 .
An example of a pressure sensitive adhesive includes an acrylic, solvent-based, pressure-sensitive adhesive that is applied at about 10 lb./ream coat weight. The pressure sensitive adhesive of layer 27 may include 4% by weight of a UV absorber such as a benzotriazole UV absorber. Such a pressure sensitive adhesive is commercially available as National Starch 80-1057. Other adhesives or adhesive types may be substituted for the PSA adhesive as can other types of UV absorbers. It should be appreciated by one of ordinary skill in the art that these UV absorbers function as stabilizers, and may be added to the present invention to protect the adhesive from deterioration (e.g., deterioration caused by sunlight). These stabilizers, however, are not required to practice the invention.
The adhesive layer, such as layer 27 , may be omitted if the combination of filters is in the form of a flexible bag or a tent.
Layer 28 used in the various embodiments of this invention is a weatherable PET UV screening film that is preferably a PET film with UV absorbers dyed into it in a sufficient amount to produce at least 2.4 optical density (OD) absorbance. A suitable PET film for layer 28 includes the film manufactured by the dyeing process described in U.S. Pat. No. 6,221,112. Other films with similar UV screening capability may be substituted for the above described film used in layer 28 .
The thickness of the PET film used to make layer 28 may be varied. For example, the film used in layer 28 in FIGS. 10 , 11 , 12 , 13 and 14 is desirably 1 mil thick to provide sufficient support for other layers used in the overall structure. The thickness of layer 28 in FIGS. 15 and 16 may be 0.5 mil thick.
The low resistance sputtered stack of layer 29 used in the various embodiments of this invention may be either the Ag/Ti or the Ag/Au stack as described herein or a similar configuration on a PET clear substrate such stacks having the sequences of: dielectric layer/IR reflecting metal layer/dielectric layer or IR reflecting metal layer/dielectric layer/IR reflecting metal layer. The low resistance stack provides higher visible light transmission.
The laminating adhesive layer 30 used in the various embodiments of the invention may be any conventional laminating adhesive including pressure sensitive adhesives known to those skilled in the art of the technological area of this invention. A useful laminating adhesive includes any conventional polyester adhesive with an isocyanate cross-linker added thereto. An example of such a laminating adhesive is Rohm and Haas's Adcote 76R36 adhesive with catalyst 9H1H. The adhesive may be applied at 1-1.5 lb. per ream coat weight. Other laminating adhesives may be substituted for the above-noted polyester-type adhesive.
Layer 31 used in the various embodiments of this invention is a clear plastic film such as clear PET that is optionally provided with a UV screening capability as described above with respect to layer 28 . Thus, the clear PET layer 31 is preferably a clear PET film that optionally has UV absorbers dyed into it in a sufficient amount to produce at least 2.4 OD absorbance. The thickness of the PET film used in layer 31 may be varied. For example, the PET film used in layer 31 of FIGS. 10 , 12 , 13 , 15 and 16 may be 0.5 mil thick. The PET of layer 31 in FIGS. 11 and 14 may be 0.5 or 1 mil thick. Also, layer 31 in FIGS. 13 and 15 is clear PET film without UV absorbers dyed into it. The PET film of layer 31 in FIG. 12 includes UV absorbers dyed into it at least 2.4 OD absorbance. The PET of layer 31 in FIGS. 10 , 11 and 14 may be either the clear PET without the UV absorbers dyed into it or may be the clear PET with UV absorbers dyed into it in a sufficient amount to produce at least 2.4 OD absorbance. The 2.4 optical density absorbance referred to herein is measured at 358 nm wavelength.
The hardcoat layer 32 used in the various embodiments of this invention may be formed from any of the hardcoat materials described herein or from any other conventional hardcoat material. Layer 32 used in the various embodiments of this invention is preferably 1-2 microns thick. The hardcoat is used to protect the combination of filters from damage and therefore the hardcoat may be omitted when the combination of filters is in a protected area where damage is not likely to occur. A suitable hardcoat composition includes the hardcoat described in U.S. Pat. No. 4,557,980, the specification of which is incorporated herein by reference.
Layer 33 used in the various embodiments of this invention is the aforementioned IR absorbing layer that preferably comprises LaB 6 and/or antimony tin oxide as a coating or film.
Layer 34 used in the various embodiments of this invention is any of the yellow films described herein. Preferably layer 34 in the various embodiments of this invention is a yellow 1 mil film Q 2186.
Layer 36 used in the various embodiments of this invention may be a 1 mil PET film or a functionally equivalent plastic film with a sputtered heat reflecting-conductive metal stack coating made up of a copper layer interposed between two nickel/chrome alloy layers. Layer 36 has a visible light transmission of about 35%. The nickel/chrome alloy layers are preferably Hastelloy C276 or Inconel 600. Layer 36 , which includes the film with the metal stack deposited thereon, preferably has a sheet resistance which is less than 8 ohms per square.
Layer 37 used in the various embodiments of this invention is a heat reflecting film of layer 14 , which preferably includes the above-discussed sputtered metal/oxide stack (described in U.S. Pat. No. 6,007,901) on a 1 mil clear weatherable polyester (PET) film. The polyester film has UV absorbers dyed into it at 2.4 or more OD UV absorbance (2.4 OD UV absorbing PET). This film may be dyed using the dyeing process described in U.S. Pat. No. 6,221,112. Other films with similar UV screening capability may be used in place of the aforementioned UV screening film.
Layer 35 used in the various embodiments of this envision is a color correcting layer. Preferably, the color correcting layer 35 is the structure described herein that contains an illuminized PET sandwiched between two gray dyed films.
According to a preferred embodiment of the present invention, two spaced apart filter combinations are utilized in combination with a window glazing unit to provide enhanced security. For example, a film comprising a combination of filters may be adhered to each side of a glazing unit (e.g., glass or plastic glazing) or one film comprising a combination of filters may be adhered to each of two spaced apart transparent sheets of a glazing unit. Alternatively, two spaced apart films each of which comprises a combination of filters may be spaced apart within the space located between two spaced apart transparent sheets of a glazing unit.
In another embodiment of the spaced apart filter combinations, each of the filter combinations are embedded (preferably completely embedded) within a PVB interlayer of a glazing unit which includes at least one PVB layer interposed between two transparent sheets of glazing material (e.g., glass or plastic). More preferably one filter combination is embedded in a first PVB interlayer and another filter combination is embedded in a second PVB interlayer spaced apart from the first PVB interlayer. An example of this more preferred embodiment is illustrated in FIGS. 18 and 19 .
The embodiment depicted in FIG. 18 includes front and rear surfaces 49 and 50 , glass layers 41 , 42 and 43 with PVB interlayer 44 interposed between glass layers 41 and 42 , and PVB interlayer 45 interposed between glass layers 42 and 43 . The PVB layers 44 and 45 fill the gap between the glass sheets and include films 47 and 48 embedded therein. Films 47 and 48 comprise any of the above-described filter combinations as a component thereof. Preferably each edge 46 of films 47 and 48 lie within the PVB so that the edges are not exposed to water, oxygen or other corrosive or harmful environmental conditions. The edges, being embedded within the PVB interlayer, thereby produce a “picture frame” configuration as shown in FIG. 19 wherein the edge 46 of film 47 (and likewise edge 46 of film 48 ) is spaced apart from the edge 51 of the entire structure.
The PVB layers are conventionally used in window manufacturing and serve to adhere the glass sheets to form a laminate which functions as a safety glass. The PVB layers used in this invention may be substituted with other similar plastic laminating layers such as polyurethane. The preferred glass layers may be substituted. with other window glazing materials such as polycarbonate and polyacrylics. Thus the embodiment depicted in FIG. 18 may use alternating layers of glass, polycarbonate and polyacrylic instead of the three glass layers.
FIG. 20 depicts an embodiment of the invention that includes a glass substrate connected to any of the filter combinations of the invention with a glass fragmentation safety film adhered thereto. In FIG. 20 , reference numeral 52 represents the combination of a glass substrate connected to any of the filter combinations of the invention and reference numeral 53 represents a flexible plastic film such as PET film adhesively secured to the combination 52 .
Another embodiment of the invention that utilizes two spaced apart filter combinations is illustrated in FIG. 21 . The embodiment depicted in FIG. 21 is glazing for a window and includes therein two spaced apart films 47 and 48 comprising any of the filter combinations described herein. Layer 54 adhesively secures film 47 to film 48 . Layer 54 may be a conventional safety glass interlayer such as PVB. Because PVB generally requires a relatively thick application to form layer 54 , layer 54 may alternatively be an adhesive forming a relatively narrower spacing between films 47 and 48 . In particular, adhesives may typically be applied in relatively thin layers, and the thickness of the adhesive may be adjusted as needed to regulate and achieve a desired spacing between films 47 and 48 .
Furthermore, the PVB or adhesive of interlayer 54 may be electrically conductive. For instance, electrical conductivity may be achieved by known techniques, such as incorporating electrically conductive particles within the layer.
The embodiment depicted in FIG. 21 may also include conventional interlayers 55 and 56 made of PVB or similar materials, and glass sheets 57 and 58 on the outer surfaces thereof.
The foregoing description of the preferred embodiments of the invention has been presented for the purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise form disclosed. Many modifications and variations are possible in light of the above teaching. For instance, various additional known materials may be added to the filtering method and system of the present invention. Specifically, the embodiments described herein include instances where the filters or combination of filters are applied onto a film such as a plastic film that, in turn, is adhered to window glazing. However it is within the scope of this invention to omit the film or films used for any filter or combination of filters and apply the filter or combination of filters onto or within a component of window glazing. It is intended that the scope of the invention be limited not by this detailed description, but rather by the claims appended hereto. Many embodiments of the invention can be made without departing from the spirit and scope of the invention. | The invention describes a system and methods for filtering electromagnetic and visual transmissions and for minimizing acoustic transmissions. Various combinations of UV, IR, and yellow-tinted filters are applied in various physical configurations to a transparent substrate such as a plastic film or glazing of a window for modifying selected wavelengths of electromagnetic radiation. For instance a light filter may have a multi-layered metallic sputtered stack having a relatively low sheet resistance. The combination of filters prevents or attenuates the passage of selected wavelengths through the substrate as needed to address security risks. The combination of filters is useful to prevent unauthorized data collection and information exchange from or within buildings or otherwise prevent such unauthorized data collection and information exchange from, for example, computer monitors or screens, personal digital assistants, and local area networks. | 1 |
CROSS REFERENCE TO RELATED APPLICATIONS
Some of the material disclosed herein is disclosed and claimed in the following pending U.S. patent application Ser. No. 09/205,391, filed Dec. 4, 1998, entitled: “FIRING CONTROL SYSTEM FOR NON-IMPACT FIRED AMMUNITION”; pending U.S. patent application Ser. No. 09/206,013, filed Dec. 4, 1998, entitled: “FIREARM HAVING AN INTELLIGENT CONTROLLER”; pending U.S. patent application Ser. No. 09/629745 filed Jul. 31, 2000 entitled: “A SECURITY APPARATUS FOR USE IN A FIREARM”; pending U.S. patent application Ser. No. 09/642753 filed Aug. 21, 2000 entitled: “AN ELECTRIC FIRING PROBE FOR DETONATING ELECTRICALLY-FIRED AMMUNITION IN A FIREARM”; pending U.S. patent application Ser. No. 09/642269 filed Aug. 18,2000 entitled: “A SLIDE ASSEMBLY FOR A FIREARM”; pending U.S. patent application Ser. No. 09/629531 filed Jul. 31, 2000 entitled: “A TRIGGER ASSEMBLY FOR USE IN A FIREARM HAVING A SECURITY APPARATUS”; pending U.S. patent application Ser. No. 09/629532 filed Jul. 31,2000 entitled: “A BACKSTRAP MODULE CONFIGURED TO RECEIVE COMPONENTS AND CIRCUITRY OF A FIREARM CAPABLE OF FIRING NON-IMPACT FIRED AMMUNITION”; pending U.S. patent application Ser. No. 09/643024 filed Aug. 21,2000 entitled: “A METHOD OF ASSEMBLING A FIREARM HAVING A SECURITY APPARATUS”; pending U.S. patent application Ser. No. 09/629534 filed Jul. 31, 2000 entitled: “AN AMMUNITION MAGAZINE FOR USE IN A FIREARM ADAPTED FOR FIRING NON-IMPACT DETONATED CARTRIDGES”; pending U.S. patent application Ser. No. 09/616722 filed Jul. 14, 2000 entitled: “AN ELECTRONICALLY FIRED REVOLVER UTILIZING PERCUSSIVELY ACTUATED CARTRIDGES”; pending U.S. patent application Ser. No. 09/616696 filed Jul. 14,2000 entitled: “AN ELECTRONIC SIGHT ASSEMBLY FOR USE WITH A FIREARM”; pending U.S. patent application Ser. No. 09/616709 filed Jul. 14, 2000 entitled: “A FIRING MECHANISM FOR USE IN A FIREARM HAVING AN ELECTRONIC FIRING PROBE FOR DISCHARGING NON-IMPACT FIRED AMMUNITION”; pending U.S. patent application Ser. No. 09/616739 filed Jul. 14, 2000 entitled: “A FIRING PROBE FOR USE IN A NON-IMPACT FIREARM”; and pending U.S. patent application Ser. No. 09/616837 filed Jul. 14, 2000 entitled: “A SECURITY APPARATUS FOR AUTHORIZING USE OF A NON-IMPACT FIREARM”, which are hereby incorporated by reference as part of the present disclosure.
FIELD OF THE INVENTION
This invention relates to firearms and, more particularly, to a backstrap module which mounts and protects a firing apparatus and security apparatus which authorize, produce, and deliver a firing signal to an electronically-discharged ammunition cartridge.
BACKGROUND OF THE INVENTION
Revolvers have been produced for over a century and, although many components in their firing mechanism have remained relatively unchanged in function and design, continuous efforts have led to improvements in safety, manufacturing, and operation of revolvers. In recent decades, the evolution of improved electronics technology and capabilities has prompted efforts to incorporate electronics into firearms to further improve the cost, manufacturability, and performance of the firearms. For example, a mechanical trigger is displaced by an electronic solenoid in U.S. Pat. No. 4,793,085, entitled “ELECTRONIC FIRING SYSTEM FOR TARGET PISTOL”. U.S. Pat. No. 5,704,153, entitled “FIREARM BATTERY AND CONTROL MODULE”, incorporates a processor into its ignition system to fire conventional percussion primers.
Electronics have also been incorporated into ignition systems for firearms that use non-conventional primers and cartridges. An “ELECTRONIC IGNITION SYSTEM FOR FIREARMS”, U.S. Pat. No. 3,650,174, describes an electronic control system for firing electronically-primed ammunition. The electronic control of the '174 Patent, however, is hard-wired and lacks the multiple sensor interfaces of the programmable central processing unit that is found with the present invention. A “GUN WITH ELECTRICALLY-FIRED CARTRIDGE”, U.S. Pat. No. 5,625,972, describes an electrically-fired gun in which a heat-sensitive primer is ignited by voltage induced across a fuse wire extending through the primer. A “COMBINED CARTRIDGE MAGAZINE AND POWER SUPPLY FOR A FIREARM”, U.S. Pat. No. 5,272,828, shows a laser ignited primer in which an optically transparent plug or window is centered in the case of the cartridge to permit laser ignition of the primer. Power requirements to energize the laser, as well as availability of fused and/or laser-ignited primers are problematic however. An “ELECTRONIC FIREARM AND PROCESS FOR CONTROLLING AN ELECTRONIC FIREARM”, U.S. Pat. No. 5,755,056, shows a firearm for firing electrically activated ammunition having a cartridge sensor and a bolt position sensor. The technology of the '056 Patent, however, is limited to a firearm with a bolt action. None of the prior art to date fully integrates an electronic control system into a revolver for consistently and effectively firing a non-impact ammunition primer. The present invention is directed to such a revolver.
OBJECTS AND SUMMARY OF THE INVENTION
One object of the present invention is to provide a backstrap module that encloses, protects and integrates a security apparatus and a firing apparatus into a revolver.
It is another object of the present invention to provide a backstrap module that secures an arrangement of sensors that communicate with the security apparatus and the firing mechanism.
According to the present invention, a backstrap module is utilized in conjunction with a firearm having a security apparatus and a firing apparatus. The security apparatus authorizes operation of the firearm and generation of an electronic firing signal which is communicated to a firing probe of the firing apparatus. The backstrap module includes a molded shell which removably affixes the backstrap module to a frame of the firearm and houses the security apparatus. The backstrap module further includes a device for communicating the firing signal to the firing probe and provides for the energizing of the security apparatus and the firing apparatus.
One advantage of the present invention is that the backstrap module is self contained and easily removable from the frame of the revolver.
These and other objects, features and advantages of the present invention will become more apparent in the light of the following detailed description of best mode embodiments thereof as illustrated in the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a rear perspective of a revolver according to the present invention showing a backstrap module and a sight assembly as assembled on a frame;
FIG. 2 is a somewhat reduced exploded perspective view of the revolver of FIG. 1 showing the backstrap module, sight assembly, and a finger grip attachment removed from the frame, and a side plate cut away to partially illustrate a firing mechanism;
FIG. 3 is a somewhat enlarged fragmentary perspective view of the revolver of FIG. 1 shown with the backstrap module separated from the frame;
FIG. 4 is a frontal perspective view of the backstrap module of FIG. 3;
FIG. 5 is a rear perspective view of the backstrap module of FIG. 3;
FIG. 6 is an enlarged rear perspective view of the finger grip attachment of FIG. 2;
FIG. 7 is a plan view of a circuit board arrangement adapted to mount within the backstrap module of FIG. 2;
FIG. 8 is an schematic side view of the circuit board arrangement of FIG. 7 shown with an array of electronics mounted thereto and installed in the backstrap module;
FIG. 9 is an enlarged, fragmented and exploded perspective view of the frame shown in FIG. 2 illustrating a disassembled firing probe assembly removed from a firing probe bore;
FIG. 10 is an enlarged, fragmented plan view of the frame of FIG. 2 shown with a small portion of the backstrap module in phantom cut away to illustrate the firing mechanism in a recovered position;
FIG. 11 is a somewhat reduced, exploded frontal perspective view of the firing mechanism of FIG. 10;
FIG. 12 is a somewhat reduced, exploded rear perspective view of the firing mechanism of FIG. 10;
FIG. 13 is a plan view similar to that of FIG. 10 except shown with the firing mechanism in a partially-cocked position;
FIG. 14 is a plan view similar to that of FIG. 10 except shown with the firing mechanism at a let-off position and the transfer bar fragmented to illustrate the hammer foot;
FIG. 15 is a plan view similar to that of FIG. 10 except shown with the firing mechanism at a fired position;
FIG. 16 is a plan view similar to that of FIG. 10 except shown with the firing mechanism at a partially recovered position;
FIG. 17 is an enlarged perspective view of the sight assembly of FIG. 2;
FIG. 18 is a fragmented perspective view of the sight assembly of FIG. 17 illustrating an arrangement of front and rear optical fibers and light gathering guides;
FIG. 19 is an enlarged perspective view of the underside of the sight assembly shown in FIG. 17; and
FIG. 20 is a schematic side view of an electrically fired revolver utilizing percussively actuated cartridges.
DETAILED DESCRIPTION OF THE INVENTION
Referring to FIGS. 1 and 2, a revolver 10 with a muzzle end shown to the left in FIG. 1, and a rear end to the right, includes a barrel 12 having a bore 13 and received in a barrel shroud 14 mounted on a frame 16 . The frame 16 has a generally rectangular opening 18 therethrough which receives a cylinder 20 rotationally hung on a yolk 21 that swings at a right angle to the frame 16 . A trigger 220 is pivotally supported on the frame 16 by a pivot pin, while a ratchet arm is pivotally attached to the trigger 220 and configured conventionally to index a plurality of cylinder chambers 24 into axial alignment with the bore 13 in a known manner. For a discussion of the function and purpose of the yoke, cylinder, and ratchet, reference is made to U.S. Pat. No. 517,152, issued to Daniel B. Wesson on Mar. 27, 1894, for a “SWINGING CYLINDER AND TRIGGER LOCK FOR REVOLVERS”, which is hereby incorporated as part of the present disclosure. The right side of the frame 16 defines an inner cavity 26 which mounts and protects an arrangement of mechanical components which cock and fire the revolver 10 , collectively referred to as a firing mechanism 27 . Conventional screws are used to attach a side plate 28 to the frame 16 to enclose the cavity 26 and prevent entry of debris into the cavity 26 . Therefore, as the revolver is held in its sighting position, the left side of the revolver is that shown in FIG. 1, and the right side shown as disassembled in FIG. 2 .
The revolver 10 of the present invention includes many mechanical components having functions understood well in the industry. However, as the revolver 10 is configured to discharge electrically-fired ammunition, such as developed by Remington Arms Company and referred to as the Conductive Primer Mix described in U.S. Pat. No. 5,646,367, many of the well-known mechanical components have been modified, eliminated, or replaced as needed.
A backstrap module 30 is configured to contain and protect most of the electronics, including a battery 31 , and the module 30 mates with the rear end of the revolver 10 in a direction indicated by arrow 32 . An ergonomically-designed finger grip attachment 34 is moved in a direction generally indicated by arrow 36 to engage the backstrap module 30 and a frame post 37 , thereby forming a conventional handgrip 38 which depends from the rear of the frame 16 . The frame post 37 has parallel, opposed side surfaces 39 and a contoured front surface 40 which are contacted by complimentary surfaces of the finger grip attachment 34 during assembly of the revolver 10 . Once the backstrap module 30 and finger grip attachment 34 are positioned onto the frame 16 , a lower mount screw 41 is inserted through the finger grip attachment 34 to secure the handgrip 38 .
A sight assembly 42 is received within a top edge 46 of the frame 16 and the barrel shroud 14 , and includes a lower housing 48 and a pair of longitudinal dovetails 50 which are oriented parallel to the top edge 46 when installed on the revolver 10 . The frame 16 has a dovetail receiver 52 concealed within the top edge 46 of the frame 16 and shroud 14 to engage the dovetails 50 . During assembly, the dovetails 50 are moved forwardly into the shroud 14 until the lower housing 48 of the slide assembly 42 is positioned over an associated housing receiver 54 in the frame 16 . The lower housing 48 is then pressed downwardly into the housing receiver 54 of the frame 16 and secured with a sight assembly mount screw 58 .
Referring to FIGS. 3-6, the backstrap module 30 includes upper and lower keys 60 , 62 which face forwardly to engage upper and lower key slots 64 , 66 of the frame 16 . The finger grip attachment 34 has parallel edges 68 , which engage associated slots 72 of the backstrap module 30 , preventing the frame 16 from releasing or disengaging from the lower portion of the module 30 . A U-shaped channel with parallel sides 78 and a forward face 80 mates against the parallel sides 39 and front surface 40 of the frame post 37 to prevent lateral movement of the finger grip attachment 34 on the frame 16 .
The backstrap module 30 includes left and right housing halves 86 , 88 which are molded from plastic and sealed together after the electronic components are arranged and mounted within the housing. The housing halves 86 , 88 are preferably injection molded from a rigid dielectric material such as Nylon or plastic which is capable of enduring the hostile environment of the revolver during normal use. The halves 86 , 88 include known types of interior features, which effectively retain and mount the electronic components.
An outer seal 90 is molded from soft-touch plastic and includes five buttons 91 configured to actuate a complimentary array of dome switches positioned underneath, as discussed in detail below, the dome switches are used by the operator to perform various operational functions prior to firing the revolver 10 , as discussed in detail below. A metallic firing probe 95 is insert molded in position during fabrication of the housing halves 86 , 88 in an orientation which will be discussed below. Two transfer bar guides 96 are located and configured to engage, support, and guide the firing mechanism 27 during later stages of its actuation. A battery holder 97 defines a generally-cylindrical, elongated blind bore sized to receive the battery 31 which energizes the circuitry in the revolver. The battery is a model DL123ABU manufactured by Duracell, but other comparable battery types are readily available.
Referring to FIGS. 7-8, a circuitboard arrangement 100 is configured for mounting within the backstrap module 30 to organize and mount the electronic components collectively referred to as a circuit assembly 101 . The circuit assembly 101 receives electronic and mechanical inputs from the operator and produces a firing signal having a minimum of 130-volt once the firing mechanism 27 has been successfully actuated.
The circuit assembly 101 is divided into two collections of components, which are referred to as a security apparatus and a firing apparatus. Each apparatus has distinct function in the overall operation of the revolver 10 . The security apparatus has the broadly defined function of authorizing the firing apparatus to produce the firing signal. Before the security apparatus authorizes the firing apparatus to produce the firing signal, a plurality of input signals must be received by the security apparatus, which are indicative of compliance with operational parameters of the revolver.
The operational parameters include: a properly entered personal identification number of a firearm operator; a signal indicating the firearm is being held properly; a signal from the firing mechanism indicating its movement toward its firing position; and a signal indicative of the firing probe contacting a properly-loaded ammunition cartridge. Each of the signals, and the specific sequence in which they are produced, is discussed in detail below.
Once the required plurality of operational parameters is received by the security apparatus, a discharge authorization signal is produced and sent to the firing apparatus. The high-voltage firing signal is produced by the firing apparatus and transmitted to the cartridge via hardware discussed in detail below. The firing apparatus includes a fly-back circuit which uses energy from the 3-volt battery to generate the high-volt firing signal using known capacitive discharge techniques.
A rigid main circuitboard 102 mounts a majority of the components, which comprise the circuit assembly 101 , and is of the general type known in the electronics industry for surface-mounting or post-mounting components. An arrangement of flexible circuitboard portions is integrated with the rigid circuitboard 102 and are configured to arrange various components in specific orientations which efficiently utilize space which is available within the module. Each flexible circuitboard portion is merely an extension of the main circuitboard but imbedded in flexible resin to maintain a flexibility that allows components to be manipulated into desired configurations and/or orientations within the backstrap module.
The circuitboard arrangement 100 includes: the main circuitboard 102 ; a first flexible portion 104 , second and third flexible portions 106 , 108 ; an input device 110 ; a high voltage mountboard 112 ; and a liquid crystal display (LCD) mountboard 114 . The first flexible portion 104 extends between the main circuitboard 102 and the input device 110 . The second flexible portion 106 extends between the main circuitboard 102 and the high-voltage mountboard 112 , and the third flexible portion 108 extends between the high-voltage mountboard 112 and the LCD mountboard 114 .
A ground strap 118 extends forwardly from the main circuitboard 102 and through the backstrap module housing to engage and electrically ground the frame 16 to the circuitboard arrangement 100 . The input device 110 is incorporated directly into the conductive elements of the arrangement 100 , and includes the dome switches 120 which are located in the handgrip 38 so that a high percentage of users is able to actuate any of the switches 120 while gripping the revolver 10 under normal operating conditions.
The high-voltage mountboard 112 mounts an arrangement of inductors, one of which is indicated by numeral 126 , a capacitor 128 , the firing probe 95 , a three-volt battery 131 , and a hammer terminal 132 . The inductor 126 is included in a “fly-back” circuit, which is energized by the battery to produce the firing signal, or energy pulse, that is stored temporarily in the capacitor 128 . The firing probe 95 includes an anchor post 134 , which is used to solder the probe 95 to the high-voltage mountboard 112 . The hammer terminal 132 is a flexible metal strip that is contacted by the firing mechanism to close an electrical input circuit in the processor.
The third flexible portion 108 extends between the high-voltage mountboard 112 and a LCD mountboard 114 . A LCD 140 is mounted to the LCD mountboard 114 and is positioned centrally between the backstrap module housing halves 86 . 88 to display electronic information for the operator in the form of readable text and/or symbols. A plurality of signals and/or information can be programmed for display on the LCD 140 , including whether or not the firearm has been authorized for use or is in the condition to be fired, and whether or not the hand grip is being grasped properly by the user. Additional information, which can be displayed includes the level of energy stored within the battery, and whether the firearm is on or is in a standby mode.
A light emitting diode (LED) 144 and photosensor circuitboard 146 are attached to the LCD mountboard 114 via a mount post 150 , and configured for use with the sight assembly 42 (seen in FIG. 2) to illuminate the front and rear sights for the revolver operator. A photosensitive cell 152 is incorporated into the photosensor circuitboard 146 to receive ambient light received from the sight assembly 42 and produce an electronic signal for the ciruitboard 146 which corresponds to the level of ambient light surrounding the revolver at any given time. Details of the circuitry within the circuitboard 146 are considered within the grasp of an individual skilled in the applicable art and will not be discussed further.
The photosensitive cell 152 is a cadmium sulfide ambient light cell manufactured by Clairex and is capable of measuring levels of ambient light and translating the levels into light corresponding signals for transmission to the processor. A high-intensity LED that has been used successfully in the revolver is a model TLGE160 manufactured by Toshiba.
An external terminal connection 156 is positioned in the handgrip 38 to receive a complimentary connector of an external device (not shown) used to communicate with the processor. The external device can be one of any number of components used for tasks such as entering an authorization code using a separate biometric or other similar device, interrogating and/or changing programmed code in the processor, changing an authorization code and/or factory serial code, determining and/or changing control parameters of certain components.
Referring to FIG. 9, a firing probe assembly 160 is assembled and engaged between the frame 16 and backstrap module 30 , and includes the firing probe 95 and a probe tip 162 biased forwardly by a probe spring 164 . An actuator bushing 168 defines a tip bore 167 with a countersunk rear end that slidably receives the probe tip 162 , the probe spring 164 , and the firing probe 95 . The actuator bushing 168 is slidably disposed within a frame bore 170 defined on the bore axis. An actuator spring 169 is captured within an annular space formed between the actuator bushing 168 and the frame bore 170 .
The firing probe 95 includes the anchor post 134 , a shank portion 172 and a tube 173 . As shown in FIG. 8, the anchor post 134 is soldered to the high voltage mountboard 112 in the backstrap module 30 . The tube 173 defines a blind bore 174 that loosely receives the probe spring 164 .
The probe tip 162 is pressed forward by the probe spring 164 into electrical contact with a cartridge in the cylinder, and includes a rounded front end and a conical rear lip 176 . The contour of the front end compliments a dimple in the primer of the cartridge so that the probe tip 162 consistently centers itself against the cartridge. The rear lip 176 is configured to be captured by a complimentary conical seat 178 defined in the tip bore 167 of the actuator bushing 168 . The probe tip 162 has a flat rear surface which bears rearwardly against the probe spring 164 at all times and against the tube 173 when the firing mechanism is recovered. Once firing probe assembly 160 is installed in the frame 16 , the probe tip 162 protrudes through the bore 167 of the actuator bushing 168 , and the rear lip 176 is captured between the conical seat 178 of the actuator bushing 168 and the tube 173 of the firing probe 95 . The probe spring 164 is selected to provide a force that is able to move the probe tip rapidly in response to actuation of the firing mechanism 27 .
The actuator bushing 168 is defined by cylindrical front and rear portions 186 , 188 having dissimilar outer diameters that form a step 190 therebetween. The counterbored tip bore 167 slidably receives the firing probe 95 , and the seat 178 retains the lip 176 of the probe tip 162 . Thus, once assembled, axial movement of the probe tip 162 in the forward direction is governed by the axial location of the seat 178 of the actuator bushing 168 . The bushing 168 has an annular drive surface 196 facing rearwardly, which is contacted by the firing mechanism as discussed in detail below.
The rear end of the frame bore 170 is double-counterbored and the front end of the bore 170 has a single counterbore 206 . The double rear counterbore forms first and second annular seats 202 , 204 which receive, respectively, the step 190 of the actuator bushing 168 and the actuator spring 169 . The actuator spring 169 fits over the front cylindrical portion 186 of the actuator bushing 168 and bears rearwardly against the step 190 of the bushing 168 and forwardly against the second seat 204 of the bore 170 . The first seat 202 of the bore 170 governs maximum forward travel of the actuator bushing 168 by engaging the step 190 of the bushing 168 .
The front counterbore 206 of the bore 170 has a diameter and depth which are selected to tightly receive an annular recoil plate bushing 210 which, with the frame 16 , forms a recoil plate 212 . The recoil plate bushing 210 defines a probe tip bore 214 aligned on the barrel axis which is configured to slidably receive the probe tip 162 that moves into and out of electrical engagement with the cartridge on the barrel axis. The bushing 210 is molded from a high-strength Zirconia ceramic material to withstand highly repetitive revolver firing forces and electrically insulate the frame 16 from the probe tip 162 . The bushing 210 has a front surface with a slightly convexed or crowned shape so that cartridges are smoothly indexed into their firing positions and axial play of any cartridge in the cylinder is taken up by the bushing 210 .
In operation, when the firing mechanism 27 is actuated with an intent to fire the revolver 10 , the drive surface 196 of the transfer bar is impacted by the firing mechanism, thereby driving the actuator bushing 168 in the forward direction. Forward movement of the actuator bushing 168 compresses the actuator spring 169 against the second seat 204 of the frame bore 170 . Accordingly, the conical seat 178 of the actuator bushing 168 is also moved forward, thereby allowing the probe tip 162 to move forward under force of the probe spring 164 .
The probe tip 162 has a low mass compared to the spring constant of the probe spring 164 , and the probe spring 164 is therefore able to move the probe tip 162 in rapid response to the axial movement of the actuator bushing 168 .
When the firing mechanism is recovered, rearward displacement of the actuator bushing, and hence the probe tip 162 , is governed or limited by the axial location of the tube 173 of the firing probe 95 . The tube 173 is located to allow the probe tip to retract a distance of approximately 0.003 inches (three thousandths of an inch) within the front surface of the bushing 210 .
Now turning to FIGS. 10 and 11, the firing mechanism 27 of the present invention differs substantially from known revolvers in both function and design, and the individual components will therefore be introduced in detail before discussing the mechanical cooperation which ultimately fires the revolver. The firing mechanism includes a trigger 220 , a hammer 222 , a sear 224 , a transfer bar 226 , a rebound 228 , a main spring 229 , a stirrup 230 , and a link 232 . A connector link 233 is coupled between the trigger 220 and the rebound 228 to compress the main spring 229 .
A rotator arm 234 , or ratchet arm, has a configuration and function known well in the industry to index the cylinder and its assembly and operation with the trigger 220 are described in detail in U.S. Pat. No. 520,468, issued to Daniel B. Wesson for “A REVOLVER LOCK MECHANISM”, and hereby incorporated by reference as part of the present disclosure.
Movement of the entire firing mechanism 27 is governed predominantly by three pivot pins which mount and secure the firing mechanism 27 in the cavity of the frame 16 . The stirrup 230 is pivotally mounted by a stirrup pin 235 , the hammer 222 is pivotally mounted by a hammer pin 236 , and the trigger is pivotally mounted by a trigger pin 237 . The frame 16 has a contoured cam surface 238 located and shaped within the cavity 26 to guide the transfer bar 226 during early stages of firing mechanism 27 actuation described below.
The trigger 220 includes a trigger post 239 with a flat upper surface, which bears generally vertically against the sear 224 during early stages of firing mechanism actuation. The trigger post 239 partially defines a trigger pocket 240 that receives the transfer bar 226 throughout the entire cycle of firing mechanism 27 actuation. The connector link 233 has a forward end pivotally attached to the trigger 220 , and a ball 241 at its rear end, which is received in a socket 242 of the rebound 228 .
The rebound 228 has an underside and lateral outer surfaces which are generally flat to allow the rebound 228 to slide freely within the cavity of the frame 16 during actuation of the firing mechanism 27 . Accordingly, the frame 16 and the side plate 28 have associated inner surfaces, which slidably retain the rebound 228 . A hammer stop 243 extends upwardly from the top side of the rebound 228 to engage the hammer 222 during recovery of the firing mechanism 27 . The rear end of the rebound 228 defines a blind bore 244 , which receives the front end of the main spring 229 . The rear end of the main spring 229 is captured within the stirrup 230 .
Referring to FIGS. 11-12, the hammer 222 includes a central core 245 , and upper and lower narrowed portions 246 , 247 straddled by upper and lower pairs of contoured cam surfaces 248 , 250 . The core 245 defines a transverse bore 252 through the hammer 222 , which receives the hammer pin 237 . The upper narrowed portion 246 has a thickness, which is less than the distance between the transfer bar guides 96 of the backstrap module 30 (shown in FIG. 6 ), so that movement of the hammer 222 is not obstructed by the backstrap module 30 . A substantially flat striker surface 256 functions as the modern counterpart to the pointed hammer portion, or firing pin, of a conventional hammer which uses inertia to ignite a conventional percussion cartridge. An upper abutment 258 extends perpendicularly from the right side of the hammer 222 and is configured to contact, or electrically engage, the hammer terminal 132 mounted to the backstrap module 30 (shown in FIG. 8) during actuation of the firing mechanism 27 . The upper cam surfaces 248 are configured to cooperate with two parallel spring members 259 of the transfer bar 226 in maintaining proper alignment and position of the transfer bar 226 with respect to the firing axis during actuation of the firing mechanism 27 .
The lower narrowed portion 246 corresponds in thickness to the upper narrowed portion 246 , and includes the lower cam surfaces 250 , a rebound abutment 262 and a hammer foot 264 . The rebound abutment 262 extends downwardly to rest against the rebound 228 when the firing mechanism is recovered. The cam surfaces 250 are configured, spaced apart, and oriented to function as rearward bearing surfaces for a pair of heels 268 of the transfer bar 226 during early stages of firing mechanism actuation. The hammer foot 264 extends generally forwardly and is configured to engage within the trigger pocket 240 of the trigger 220 during the later stages of firing mechanism actuation.
The hammer 222 also defines a sear pocket 270 configured to retain and control movement of the sear 224 . A pivot point 272 of the sear 224 rests in a corner 276 of the sear pocket 270 , and a lip 278 of the sear 224 engages a complimentary edge 280 of the sear pocket 270 , thereby effectively defining the range of angular motion of the sear 224 within the sear pocket 270 . A sear spring 284 is disposed between the sear 224 and sear pocket 270 to bias the sear 224 outwardly into engagement with the hammer trigger post 239 .
A link pocket 288 is defined on the underside of the hammer 222 to receive and pivotally retain a forward hook 290 of the link 232 . The link pocket 088 is partially enclosed on its left and right sides so that the link 232 remains centered within the link pocket 288 during firing mechanism actuation. The link 232 includes a rear hook 294 configured with a shape similar to that of the forward hook 290 to pivotally engage the stirrup 230 .
The front side of the stirrup 230 defines a blind, tapered bore 298 , and a transverse link pin 299 is molded into an upper end of the stirrup during fabrication. The link pin 299 pivotally receives the rear hook 294 of the link 232 , and the blind bore 298 receives the main spring 229 . The aforementioned taper in the bore 298 prevents the stirrup 230 from binding the main spring 229 during firing mechanism actuation.
The transfer bar 226 is configured to be moved by the trigger 220 into and out of engagement with the actuator bushing 168 , and includes the spring members 259 , left and right legs 310 , and a forked upper end 312 . The legs 310 are spaced apart from one another to loosely straddle the sear 224 and lower narrowed portion 247 of the hammer 222 , and each leg 310 includes a heel 268 and a foot 314 . Each foot 314 extends forwardly into the trigger pocket 240 of the trigger 220 , and each heel 268 bears rearwardly against one of the lower cam surfaces 250 of the hammer 222 during initial stages of firing mechanism actuation.
The forked upper end 312 includes left and right driver surfaces 315 , which straddle the firing probe assembly and rest against the actuator bushing when the transfer bar is in its firing position. A flat yoke 316 faces rearwardly to receive a hammer blow when the firing mechanism is actuation. In other words, when the transfer bar is in its firing position, the yoke 316 is aligned in the rotational path of the striker surface 256 of the hammer 222 . In the firing position, the front side of the upper end 312 rests against the annular drive surface 196 of the actuator bushing 168 on diametrically opposed sides of the bore 167 . The transfer bar 226 is molded from nylon or other dielectric material capable of withstanding highly repetitive impact forces from the hammer 222 during normal use of the revolver.
During initial stages of firing mechanism 27 actuation, the transfer bar 226 bears against the contoured cam surface 238 of the frame 16 while moving upwardly in the aforementioned camming action toward the firing probe assembly 160 . When moved further toward the firing position by the trigger 220 , the upper end 312 of the transfer bar 226 bears rearwardly against the transfer bar guides 96 of the backstrap module 30 . The guides 96 ensure that the transfer bar 226 is aligned properly with the actuator bushing 168 before being struck by the hammer 222 . Proper transfer bar alignment ensures that the impact force of the hammer 222 is transmitted properly and smoothly along the barrel axis without jamming or cocking the actuator bushing 168 in the frame 16 .
The spring members 259 extend from the rear side of the transfer bar 226 generally in the downward direction to straddle the upper narrowed portion 246 of the hammer 222 and bear against the upper cam surfaces 248 during initial actuation stages of the firing mechanism 27 . The spring members 259 act in unison to assist alignment between the transfer bar 226 and the firing probe assembly 160 .
Operation of the firing mechanism 27 is best explained with reference to several known stages of actuation, including: a recovered position shown in FIG. 10; a partially-cocked position shown in FIG. 13, where the trigger is being pulled by the operator; a “let-off” position shown in FIG. 14, beyond which point the trigger disengages from the sear and allows the hammer to fall; a fired position shown in FIG. 15, where the hammer has fallen and impacted the actuator bushing; and a partially-recovered position shown in FIG. 16, where the operator has partially released the trigger toward the recovered position to complete a cycle of the firing mechanism.
Referring back to FIG. 10, the trigger post 239 of the trigger 220 is not loaded against the sear 224 when the firing mechanism is in the recovered position. Instead, the hammer 222 is resting against the hammer stop 243 of the rebound 228 . The foot 210 of the transfer bar 226 is captured within the trigger pocket 240 , and the spring members 259 of the transfer bar 226 are unloaded by the hammer 222 .
When the trigger 220 is pulled, as shown in FIG. 13, the trigger post 239 rotates upwardly into contact with the sear 224 and the sear 224 forces the hammer 222 into a counterclockwise rotation. Rotation of the hammer 222 forces the stirrup 230 , via the link 232 , to rotate in a clockwise direction. It is apparent, then, that when the trigger 220 is pulled, the rebound 228 is pushed rearwardly and compresses the main spring 229 . Simultaneously, however, because the trigger 220 rotates the stirrup 230 via the hammer and link, the mainspring 229 is compressed further from the rear.
In this early stage of actuation, the spring members 259 bear against the upper cam surface of the hammer 222 . Accordingly, the transfer bar 226 is pushed generally forwardly and into the camming action against the contoured surface 238 of the frame 16 .
As the hammer 222 is rotated by the sear 224 , the contour of the upper cam surfaces 248 effectively moves the cam surfaces 248 away from the spring members 259 as the hammer rotates. The transfer bar 226 is simultaneously pushed upwardly and engaged against the transfer bar guides 96 of the backstrap module 30 (seen in FIG. 3 ). Eventually, the sear 224 reaches a point where it can no longer remain engaged with the trigger post 239 of the trigger 220 . At this point, the foot 264 of the hammer 222 is configured to engage itself within the trigger pocket 240 of the trigger 220 . Accordingly, the hammer 222 is rotated further in the counterclockwise direction and the main spring 229 is compressed further at its front and rear ends.
Referring to FIG. 14, the “let-off” point (point just prior to let-off is indicated by arrow 255 ) is reached when the foot 264 of the hammer 222 can no longer remain engaged within the trigger pocket 240 with continued rotation of the trigger 220 . At this point, the main spring 229 is fully compressed and the transfer bar 226 has reached the firing position at rest against the annular drive surface 196 actuator bushing 168 (the forked upper end 266 is seen from its side in the reference figure). Once the hammer 222 disengages from the trigger 220 , as seen in FIG. 15, the hammer rotates immediately toward the transfer bar 226 under force of the compressed main spring 229 . Just before striking the transfer bar 226 , the hammer 222 engages the hammer terminal 132 hanging from the backstrap module 30 , thereby closing an input circuit in the processor. The closed firing circuit signals the processor that let-off has occurred and that the hammer is about to strike the transfer bar 226 .
Referring to FIG. 16, as the trigger 220 is released, or recovered, by the operator, counterclockwise rotation of the trigger moves the trigger post 239 downwardly along the sear 224 . The sear 224 is forced to pivot within the sear pocket of the hammer 222 and against the sear spring until the trigger post 239 is rotated beyond mechanical engagement with the sear 224 . The sear is then pushed outwardly away from the hammer 222 by the sear spring and is therefore prepared to be engaged by the trigger post 239 in a subsequent actuation of the firing mechanism 27 .
Forward movement of the connector link 232 allows the rebound 228 to be pushed by the main spring 229 in a forward direction within the frame 16 , thereby moving the hammer stop 243 into engagement with the lower abutment 262 of the hammer 222 . Once the rebound 228 engages the lower abutment 262 of the hammer 222 , the hammer 222 is forced to rotate slightly in the counterclockwise direction, until the trigger reaches the fully-recovered position. Throughout the recovery action, the transfer bar 226 remains engaged within the trigger pocket 240 of the trigger 220 and is pulled downwardly with counterclockwise trigger rotation.
Referring to FIGS. 17-19, the sight assembly 42 is configured with front and rear sights, which illuminate according to the level of ambient light surrounding the revolver. In particular, the sight assembly gathers and projects the ambient light toward the photosensitive cell 152 of the backstrap module 30 (seen in FIG. 8) and, in turn, receives and projects toward the firearm operator an amount of high intensity light emitted from the LED 144 . The sight assembly 42 includes a molded plastic sight frame 340 , a single front optical fiber 342 , a pair of rear optical fibers 344 and front and rear ambient light guides 346 , 347 .
The sight frame 340 includes the pair of parallel dovetails 50 introduced in FIG. 2 and front and rear sight housings 348 , 350 formed at opposite ends of an elongated, flexible body portion 352 . The dovetails 50 (only one of the two is shown in FIG. 17) extend rearwardly from the front end of the sight frame 340 and are short enough to be concealed entirely within the shroud 14 when the revolver 10 is assembled. A front fiber channel 354 secures and protects the front fiber 342 and is configured to aim a terminal end 356 of the front optical fiber 342 toward the rear of the revolver 10 . A pair of rear fiber channels 360 secure and protect the rear fibers 344 , and aim terminal ends 364 of the rear optical fiber 344 toward the rear of the revolver 10 .
The three channels 354 , 360 meet and join together at a rearwardly facing interface panel 366 depending from the underside of the rear sight housing 350 . The interface panel 366 defines an aperture 370 , which bundles the optical fibers 342 , 344 in the channel 354 , 360 and aims the fibers toward the LED 144 of the backstrap module 30 .
The rear sight housing 350 defines a notch 374 between the terminal ends 364 of the rear sight fibers 344 to provide the operator with a line of sight of the front optical fiber 342 when the revolver is held in a normal sighting position. Therefore, if desired during use, the operator can visually align the front fiber 342 between the two rear optical fibers 344 . In other words, the notch 374 prevents the rear sight housing 350 from obstructing the view of the front fiber 342 .
The front and rear ambient light gathering guides 346 , 347 are insert-molded into the rear sight housing 350 of the sight frame 340 to receive ambient light, respectively, from areas generally fore and aft of the revolver 10 . The guides 346 , 347 curve downwardly and join together at a horizontal interface 382 to project the gathered light collectively upon the photosensor 152 introduced in FIG. 8 . The interface 382 defines an aperture 383 , which is configured to bundle and aim the front and rear ambient light guides 346 , 347 downwardly at the photosensor 152 in the backstrap module 30 . The horizontal interface 382 is purposely oriented perpendicular to the interface panel 366 so that light emitted from the LED does not inadvertently enter the photosensor 152 and adversely effect operation of the sight assembly.
As seen in FIG. 19, the lower housing 48 of the sight frame 340 is formed by the interface panel 366 and opposed side walls 384 , 386 . Each side wall has an laterally-facing key 388 which is received within the receiver 54 of the frame 16 (seen in FIG. 3 ).
A metallic cylindrical sleeve 391 is insert molded into the frame 340 to receive the mount screw 58 (seen in FIG. 2) without damaging the material of the sight frame 340 . The interior of the lower housing 48 is filled with a potting material such as silicon rubber after the light fibers are installed.
The sight assembly 42 cooperates with electronics within the backstrap module to illuminate the front and rear sights and assist the operator in sighting the revolver under various lighting conditions. The sights are configured so that the light emitted from them can be detected by a firearm operator holding the revolver in a normal sighting position. The brightness with which the sights are illuminated varies automatically depending on the level of ambient light surrounding the revolver 10 . For instance, in certain ambient conditions where the front and rear sights are not easily discerned by the operator, the sights are illuminated brightly to improve contrast between the sights and the surrounding environment. On the other hand, brightly illuminated sights are not required, and may in fact hinder the sighting process, in a dark environment.
The sight assembly operates by projecting gathered light upon the photosensor 152 mounted in the backstrap module 30 . The photosensor 152 converts the light to an associated signal, and circuitry within the photosensor circuitboard 146 uses the signal to calculate an appropriate level of illumination for the front and rear sights. The LED is then provided with enough energy to illuminate the front and rear sights.
Turning now to a discussion of details of operation of the revolver shown in FIGS. 1-19, the security apparatus is programmed with three operational modes: a sleep mode, an awake mode, and an authorized or “intent-to-fire” mode. There is no “on/off” switch for the revolver, so one of the three operational modes is always active. The least active of the modes is the sleep mode, which deactivates the LCD when the revolver is left alone for more than three (3) minutes. This mode is related to a feature known as a “slow grip,” where the security apparatus automatically reverts to the sleep mode from any other mode to save battery energy when the revolver has not been handled for the predetermined amount of time. The slow grip also deactivates the revolver an prevents unauthorized use in the event that the operator neglects to deactivate the revolver himself or herself. The awake mode is activated by actuating any of the input switches on the hand grip. Hence, the first method in which the input switches can be used is to wake the revolver from the sleep mode.
Once the awake mode has been activated, the security apparatus is prepared to receive entry of an authorization code from the operator. Additionally, the awake mode activates the LCD screen, which indicates the various forms of information discussed above. The input switches on the handgrip are used by the operator to enter his or her authorization code by depressing a personalized sequence of switches. However, when the revolver is initially purchased from a dealership or the factory, the operator must enter a manufacturing code set at the factory which corresponds to the serial number of the revolver frame. Once the operator enters the proper manufacturing code, the security apparatus will then accept entry of his or her own personalized authorization code. After the manufacturing code has been changed, the personalized authorization code is the only code needed to operate the revolver. It is apparent that the security apparatus can be programmed with an algorithm, which allows the operator to change the authorization code if desired.
The security apparatus uses two mechanisms to inform the operator when the authorization code has been properly entered. A signal is displayed on the LCD, and the front and rear sights are “blinked on”, or illuminated, for a time period of 300 milliseconds. Proper entry of the authorization code activates the “intent-to-fire” mode in the security apparatus and the revolver is capable of being discharged provided the remainder of the input signals are received by the security apparatus.
The input switches provide one of the remaining input signals by signaling the security apparatus when the revolver is being gripped by the operator in a manner deemed sufficient and consistent with an intent to fire the revolver. Experiments have shown that the average operator can consistently and simultaneously depress any two of the five input switches. Accordingly, the security apparatus will not authorize a discharge of the revolver unless at least two of the five input switches are depressed. The LCD can include a signal, which informs the operator that the handgrip is being grasped properly. The proper grip is also the mechanism which activates the illuminated sight assembly. As long as the proper grip is maintained, the front and rear sights are illuminated automatically at an intensity level which corresponds to the level of ambient light.
In the event that the operator wishes to deactivate the intent-to-fire mode, the input switches can be used to enter a cancellation code, which re-activates the awake mode of the security apparatus. Without the cancellation code, the revolver could be fired, for instance, by an unauthorized individual after being put down by the authorized operator for a time period that is less than that associated with the slow grip feature discussed above. The cancellation code is obviously a function, which can be personalized, but a representative code is three consecutive actuations of the bottom input switch.
Once the security apparatus receives a valid authorization code and senses that the revolver is being gripped properly, the security apparatus signals the firing apparatus to provide the firing probe with a low-voltage check signal. Because the probe tip does not contact the cartridge until the firing mechanism has been actuated, the check signal is not conducted further than the probe tip and is not registered by the security apparatus. When the probe tip contacts the cartridge after the firing mechanism has been actuated, the check signal from the firing apparatus is sensed by the security apparatus, thereby informing the security apparatus that a cartridge is positioned properly for discharge.
Once the operator is properly authorized, the revolver can be discharged by cycling the firing mechanism, or pulling the trigger beyond the let-off position, provided the security apparatus receives the last two signals: the check signal and the firing mechanism signal. When the hammer falls after cycling the firing mechanism, the hammer strap is contacted by the hammer, thereby signaling the security apparatus that the firing mechanism has been actuated. Almost instantaneously after the hammer strap is contacted, the probe tip is moved into contact with the cartridge, thereby signaling the security apparatus that a cartridge is properly loaded. If so, the security apparatus authorizes the firing apparatus to produce and communicate the 150-volt firing signal to firing probe to discharge the cartridge.
The revolver cannot be discharged successively without cycling the firing mechanism beyond the let-off position. First, the security apparatus is programmed with circuitry that can only be reset by releasing the hammer from engagement with the hammer strap. The hammer can only be reset by recovering the trigger after firearm discharge, and cycling the firing mechanism again.
Another feature of the revolver which precludes inadvertent discharges results from the configuration of the firing mechanism and transfer bar. After the firearm is discharged, the transfer bar remains at its firing position until the trigger is recovered, thereby pulling the transfer bar out of contact with the actuator bushing. The transfer bar cannot be returned to its firing position against the actuator bushing unless the firing mechanism is cycled to the let-off position. Therefore, even assuming an unfired cartridge is positioned for discharge, a firing signal will not be authorized, much less produced, for instance by dropping the revolver, because the transfer bar is not in the position to move the probe tip into contact with the cartridge.
Referring to FIG. 20, a revolver 10 ′ is configured to discharge conventional, percussively primed cartridges, and includes a backstrap module 30 ′ and means 31 ′ adapted to actuate a mechanical firing pin such as that shown and disclosed in U.S. Pat. No. 4,793,085, which is hereby incorporated by reference into the present invention. It is considered within the grasp of a person skilled in the art to adapt the security apparatus of the present invention to supply an electronic signal which is utilized to initiate movement of a solenoid or similar device to convert the electrical signal into mechanical movement which is sufficient to detonate a conventional percussive cartridge primer.
While preferred embodiments have been shown and described above, various modifications and substitutions may be made without departing from the spirit and scope of the invention. For example, various other forms of information can be displayed on the LCD display screen for the operator, including an indication of cartridges in any of the cylinder chambers. In addition, different arrangements of electronics within the backstrap module is considered within the scope of the present invention to accommodate various revolver configurations. For instance, smaller revolver sizes may require different component arrangements to avoid effecting operator comfort. Still further, it is considered within the scope of the present invention to replace the mechanically-actuated trigger with other known types of switches for releasing the firing mechanism.
Still even further, the backstrap module may assume various other configurations which allow for modifications or improvements to manufacturing procedures, such as forming the backstrap module from front and rear housing halves instead of left and right housing halves. With such a configuration, it may be found more advantageous and economical to assemble and mount the circuitboards to a front housing half and permanently mate the front and rear housing halves once circuitry is secured.
It is also considered within the scope of the present invention to provide alternate configurations of the firing probe assembly, which facilitate and economize production and assembly procedures. For instance, the firing probe may include a hollow bore adapted to receive an elongated wire extending from the rear of the probe spring. The elongated wire is inserted through the firing probe and soldered directly to the high-voltage mountboard, thereby obviating the need to solder the firing probe to the mountboard while ensuring proper alignment of the probe, actuator bushing, and probe tip.
Still even further, it is considered within the scope of a person skilled in the art of electromechanical design to adapt the security apparatus for use in firing percussively discharged cartridges. Such an integration would involve fitting apparatus to a conventional firing pin which would accept an electronic signal from the security apparatus which is indicative of an intent to fire the revolver. For instance, the security apparatus can provide an appropriate signal to a solenoid of sorts, which solenoid can release the firing pin to impact the cartridge.
Yet even further, it is considered within the scope of the present invention to provide a security apparatus which utilizes an alternate method of authorizing an operator, such as with a system which recognizes the voice or biometrics of the operator, a specific sound, or even a certain radio signal.
Accordingly, it is to be understood that the present invention has been described by way of illustration and not by way of limitation. | According to the present invention, a backstrap module is utilized in conjunction with a firearm having a security apparatus and a firing apparatus. The security apparatus authorizes operation of the firearm and generation of an electronic firing signal which is communicated to a firing probe of the firing apparatus. The backstrap module includes a molded shell which removably affixes the backstrap module to a frame of the firearm and houses the security apparatus. The backstrap module further includes a device for communicating the firing signal to the firing probe and provides for the energizing of the security apparatus and the firing apparatus. | 5 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to luggage and more particularly, to a luggage inflatable structure which has a piston mounted on the bottom side of the pull rod of the luggage and movable up and down with the pull rod in a sleeve inside the luggage to pump air into a air bag so that storage items are held firmly in position when the air bag is inflated, avoiding storage item damage or noises during carrying or delivery of the luggage.
[0003] 2. Description of the Related Art
[0004] When carrying or delivering a luggage, the items stored in the luggage may be forced to hit one against another, causing storage item damage or producing noises. Air bags or elastic cushion pads may be set in a luggage to hold down storage items in place. However, when the volume of the storage items is changed following traveling, the air bags or elastic cushion pads may be unable to hold down the storage items in place. In this case, storage item damage or noises may occur.
[0005] Further, US 2004/0035185 teaches the use of an inflation connector for the connection of an air pump to pump air into the luggage.
SUMMARY OF THE INVENTION
[0006] The present invention has been accomplished under the circumstances in view.
[0007] It is therefore the main object of the present invention to provide a luggage inflatable structure, which allows inflation of an air bag to any status subject to the amount of storage items in the luggage, enabling the storage items to be firmly held in place between the peripheral wall of the housing of the luggage and a bottom lining when the user is carrying the luggage or when the luggage is being delivered, avoiding storage item damage or noises.
[0008] It is another object of the present invention to provide a luggage inflatable structure, which has a simple structure, requires less installation space, and fully utilizes the internal space of the luggage.
BRIEF DESCRIPTION OF THE DRAWING
[0009] FIG. 1 is a schematic sectional view of a luggage having an inflatable structure in accordance with the present invention.
[0010] FIG. 2 is a schematic section view of the present invention, illustrating storage items accommodated in the luggage and the air bag flattened.
[0011] FIG. 3 corresponds to FIG. 2 , illustrating the air bag inflated.
DETAILED DESCRIPTION OF THE INVENTION
[0012] Referring to FIGS. 1˜3 , an inflatable structure of a luggage in accordance with the present invention is shown comprising:
[0013] at least one sleeve 1 fixedly mounted between an upper locating block 52 and a lower locating block 53 at one side in a housing 51 of a luggage 5 with fastening members 56 ; 57 and defining a bottom air inlet 14 that is connected to an air intake pipe 11 in the luggage 5 and an axial piston hole 10 that receives a pull rod 2 , where the upper locating block 52 has a locating groove 521 for the positioning of the top end of the sleeve 1 ; the lower locating block 53 has a locating hole 531 for the positioning of the bottom end of the sleeve 1 and a fastening member 532 mounted in the locating hole 531 to affix the bottom end of the sleeve 1 ;
[0014] at least one pull rod 2 that has its bottom end 22 inserted the axial piston hole 10 of the sleeve 1 and fixedly connected with a piston 20 and its top end provided with a grip 21 and is movable up and down in the axial piston hole 10 of the sleeve 1 to pump air through the air intake pipe 11 into an air bag 3 ;
[0015] an air bag 3 mounted in one side inside the housing 51 of the luggage 5 between a bottom lining 54 and the sleeve 1 and having an air pipe 35 connected to the air intake pipe 11 for guiding pumped air from the sleeve 1 into the air bag 3 for enabling the air bag 3 to be inflated upon reciprocating motion of the piston 20 with the pull rod 2 in the axial piston hole 10 of the sleeve 1 , wherein the bottom lining 54 can be a rigid sheet member, or a fabric, synthetic leather or flexible sheet member connected to the housing 51 of the luggage 5 ; and
[0016] an air-valve switch 4 , which comprises a first air port 41 connected to the air intake pipe 11 , a second air port 42 connected to the air pipe 35 of the air bag 3 , an exhaust pipe 43 connected to a through hole 511 on the peripheral wall of the housing 51 of the luggage 5 and an operation panel 44 with an air intake control key (not shown) and an exhaust control key (not shown), wherein when the air intake control key is switched on, the first air port 41 and the second air port 42 are opened and the exhaust pipe 43 is closed for enabling pumped air to flow through the air-valve switch 4 and the air pipe 35 into the air bag 3 ; when the exhaust control key is switched on, the first air port 41 is closed, the second air port 42 and the exhaust pipe 43 are opened, for enabling air to be exhausted out of the air bag 3 through the air pipe 35 , the second air port 42 and the exhaust pipe 43 .
[0017] Further, the top end of the sleeve 1 is covered with a cap 12 that has a through hole 121 for the passing of the bottom end 22 of the pull rod 2 .
[0018] Further, an one-way valve 111 is installed in the air intake pipe 11 of the sleeve 1 for allowing air to flow in direction from the sleeve 1 toward the air pipe 35 of the air bag 3 and prohibiting backward flowing of air from the air pipe 35 toward the inside of the sleeve 1 .
[0019] Further, the air-valve switch 4 is mounted in a switch hole 512 on the peripheral wall of the housing 51 of the luggage 5 , keeping operation panel 44 on the outside of the luggage 5 for operation by a user.
[0020] Further, the air bag 3 is a hollow inflatable container made of a flexible rubber material having a high deformation rate.
[0021] As stated above, the piston 20 is fixedly connected to the bottom end of the pull rod 2 and movable up and down with the pull rod 2 in the axial piston hole 10 of the sleeve 1 to pump air through the air intake pipe 11 into the air bag 3 . When the air bag 3 is inflated, it imparts a pressure to the bottom lining 54 against the storage items 6 in the housing 51 of the luggage 5 (see FIG. 3 ), holding the storage items 6 firmly in place against displacement. Therefore, when carrying or delivering the luggage 5 , the storage items 6 are firmly held in position and will not hit against one another, avoiding storage item damage or noises. After each use, the internal air of the air bag 3 can be exhausted through the exhaust pipe 43 of the air valve switch 4 (see FIG. 2 ).
[0022] In conclusion, the invention has advantages as follows:
1. All storage items, no matter how much the amount, can be held firmly in place between the peripheral wall of the housing 51 of the luggage 5 and the bottom lining 54 when the air bag 3 is inflated when the user is carrying the luggage 5 or when the luggage 5 is being delivered, avoiding storage item damage or noises. 2. Subject to the arrangement of the piston 20 at the bottom end of the pull rod 2 , the air intake pipe 11 at the bottom side of the sleeve 1 and the air-valve switch 4 in between the air bag 3 and the air intake pipe 11 , the inflatable structure of the present invention has a simple structure, requires less installation space, and fully utilizes the internal space of the luggage. 3. The operation of the inflatable structure is easy. The user can be inflated or flattened conveniently when desired. It is not necessary to use an external air pump when wishing to inflate the air bag. | A luggage inflatable structure includes a sleeve fixedly mounted in the housing of a luggage, an air bag received in a bottom lining and the periphery of the housing of the luggage, and a pull rod having a piston located on the bottom end thereof and movable up and down in the sleeve for pumping air into the air bag so that storage items are held firmly in position when the air bag is inflated, avoiding storage item damage or noises during carrying or delivery of the luggage. | 0 |
BACKGROUND OF THE INVENTION
Sliding doors such as arcadia doors are widely used in homes, apartment buildings, and many commercial establishments, particularly for use as patio doors or the like. These doors offer the advantage of a wide expanse of glass and, since they do not swing inwardly or outwardly, do not intrude upon the space on either side of the door which then can be utilized in any manner desired. A disadvantage of such doors is that once they are opened, they require a positive effort to reclose. This is particularly disadvantageous for home owners with small children who typically forget it reclose the door after they open it and pass through it.
Door closers which automatically close sliding or arcadia doors have been developed to automatically reclose such doors after they have been opened. Most of these door closers are bulky and unattractive, so that they have not proved popular in home and apartment applications in particular.
A compact and effective sliding door closer which does not have the unslightly bulk of typical closers is disclosed in my prior U.S. Pat. No. 3,278,979 issued Oct. 18, 1966. While the closer disclosed in this patent effectively operates to automatically reclose sliding doors after they have been opened and permits a simple adjustment of the rate of closure, the locking of the door and maintaining the door in a partly open condition required the operation of a thumb screw. While the thumb screw was effective to accomplish the desired purpose, it was relatively inconvenient to use and did not provide as strong a lock for the door in the fully closed position as is now desirable.
Accordingly, it is desirable to provide an improved sliding door closer which may be securely locked in the closed position, operated with the automatic closer mechanism functioning, or operated as a normal sliding door without any action from the closer whatsoever. It is desirable that these three different modes of operation may be readily selected and controlled one to the other simply and effectively.
SUMMARY OF THE INVENTION
Accordingly, it is an object of this invention to provide an improved automatic door closer for sliding doors.
It is another object of this invention to provide an automatic door closer which may be readily changed from an automatic operation to a conventional operation and back again.
It is an additional object of this invention to provide an improved lock for a sliding door.
It is a further object of this invention to provide a sliding door closer and lock combination which is compact and simple to install.
In accordance with a preferred embodiment of the invention, a sliding door closer comprises inner and outer mutually telescoping tubes which are movable between closed and extended positions. A spring is attached under tension between the tubes to bias them to the closed position. A first bracket is attached to the corner of the frame in which a sliding door slides and a second bracket is secured to the mating corner of the sliding door and to one end of the outer tube of the two telescoping tubes. The inner telescoping tube has an extension on it which extends beyond the one end of the outer tube and this extension has a latch engaging hole in it. In order to effect three different modes of operation of the door, a locking device is employed for selectively (1) interlocking at least the first and second brackets together to lock the door in a closed position, (2) interlocking at least the first bracket and the latch engaging member on the extension means on the inner tube to permit operation of the door utilizing the automatic closure feature or (3) permitting independent movement of the second bracket and the latch engaging member relative to the first bracket, so that the door can be used in a conventional manner as if the closer mechanism were not present.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a partial perspective view of a typical sliding door which has the closer mechanism of a preferred embodiment of the invention attached to it and to the door frame;
FIG. 2 is an exploded view of details of the embodiment shown in FIG. 1;
FIG. 3 is a partially cut-away sectional view taken along the lines 3--3 of FIG. 2;
FIG. 4 is a sectional view taken along the lines 4--4 of FIG. 2;
FIG. 5 is a sectional view taken along the lines 5--5 of FIG. 4; and
FIG. 6 is a sectional view taken along the lines 6--6 of FIG. 5.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
In the drawings, the same reference numbers are used throughout the several figures to designate the same or similar components.
Referring now to FIG. 1, there is shown a typical sliding arcadia door 10 mounted for sliding movement in a frame 11. The hardward comprising the door closure and locking device in accordance with a preferred embodiment of the invention is illustrated by a first bracket 13 attached to the upper right-hand corner of the frame 11 and a second bracket 15 attached to the door 10 at its upper edge and adjacent the right-hand edge as viewed in FIG. 1. The brackets 13 and 15 then cooperate with an inner tube 16 and an outer tube 17 which are mounted in a telescoping relationship to comprise the primary parts of the automatic door closure.
Referring now to FIG. 2, the details of the brackets 13 and 15 along with portions of the details of the telescoped inner and outer tubes 16 and 17, respectively, are shown. The corner bracket 13 is a generally E-shaped bracket with a vertical portion 20 and an upper horizontal leg 21 which fits into the corner of the frame 11 on either the right-hand or left-hand side in accordance with the direction of opening of the door 10.
To properly align the bracket 13 into the corner of the door frame, an L-shaped flange 23 (one of which is on each side of the bracket 13) extends into the corner of the frame 11 and locates the sides of the portions 20 and 21 adjacent the corner of the frame 11. When the bracket 13 is in this location, as shown most clearly in FIG. 1, screws are inserted through six holes 24 extending through the leg 21 and the vertical portion 20 to mount the bracket 13 firmly into the corner in which it is placed. As most clearly shown in FIG. 2, the bracket 13 includes a central leg 26 and a lower leg 27 extending outwardly from the vertical portion 20 parallel with the upper leg 21.
A series of aligned holes 29, 30 and 31 are formed through the legs 21, 26 and 27, respectively, of the bracket 13 to accommodate the vertical travel of a locking rod 32 through them. The alignment of these holes and the configuration of the rod 32 is shown most clearly in FIGS. 4 and 5.
The locking rod 32 is vertically movable to any one of three detented positions which are established by three detents or indentations 34, 35 and 36, on the rod. The upper end of the rod 32, the lower edge of the indentation 36, and the edges of the indentations 34 and 35 all are beveled to form cam surfaces to act in conjunction with a spring biased follower 37 located in a passageway through the portion 20 and extending through the lower leg 27 to the hole 31 in the leg 27.
In assembling the locking rod 32 into the bracket 13, the locking rod 32 is first inserted into a position extending through the leg 27 past the passageway in which the follower 37 is inserted. Then the follower 37 is inserted into the passageway, a spring 40 is placed in the passageway behind the follower 37 and a plug 41 compresses the spring 40 and closes the passageway through the vertical portion 20 of the bracket 13. Once the plug 14 is in place, it is brazed or glued to hold it securely in this permanent position.
To prevent accidental removal of the locking rod 32 after the follower 37 and spring 40 are in place, the upper edge of the indentation 36 is cut straight across, that is it is not a cam surface. The corresponding edge of the follower cylinder 37 also is essentially a nonbeveled edge; so that when the locking lever 32 is pulled to its lowermost position causing the follower 37 to press into the indentation 36, the abrupt lip of the upper edge of the indentation 36 engages the side of the cylindrical follower 37 and prevents further downward travel of the locking bar 32. Upward travel of the locking bar 32 is limited by the handle portion 44 which extends substantially at right angles to the rod 32, as seen most clearly in FIG. 2.
Once the bracket 13 is attached to the corner of the frame in which the sliding door slides and the locking bar 32 is in place as described above, the locking bar may be moved vertically to any one of its three detented positions. In the lowermost position with the follower 37 in the detent 36, the locking bar is entirely within and below the leg 27 of the bracket 37. Thus, the space between the legs 21 and 26 and between the legs 26 and 27 is free of the locking bar. In its center detented position, with the follower 37 in the detent 35, the upper end of the locking bar 32 is within the leg 36 in the hole 30; so that the locking bar 32 passes through the space between the legs 26 and 27. In this position, however, the space between the legs 21 and 26 still is open. In the uppermost position of the locking bar 32, with the follower 37 in the detent 34, the locking bar is in the dotted line position illustrated in FIG. 4 with the upper end located within the upper leg 21 of the bracket 13. In this position, the locking bar passes through the spaces between all of the legs of the bracket 13.
Reference now should be made back to FIGS. 1 and 2 which illustrate the details of the mounting bracket 15 attached to the door and to the outer tube 17 of the door closer. The bracket 15, as shown most clearly in FIG. 2, is partially bifurcated by a slot 47 in its upper horizontal leg 48. The bifurcation 47 terminates in a key-shaped slot 50 located near the left-hand end of the bracket 15, as shown in FIG. 2. Four parallel holes 53 are formed through the bracket 15 and are used for fastening the bracket 15 to the door 10 by means of screws extending through the holes 53.
Underneath the portion 48 of the bracket 15 is a cylindrically shaped tube receiving portion 55 integrally formed with the bracket. This tube receiving portion 55 does not extend all the way to the left-hand edge of the bracket 15, as is apparent from an examination of FIG. 2, and as is illustrated in dotted lines in FIG. 4. Thus, the left-hand end of the portion 48 (as viewed in FIG. 2) which has the hole 50 in it is shaped to extend into the space between the legs 21 and 26 of the bracket 13 when the assembly is made as illustrated in FIG. 1 and with the alignment most clearly shown in FIG. 4. In this position, the slot 50 is aligned with the holes 29 and 30 in the legs 21 and 26 of the bracket 13. When the screws through the holes 53 are tightened to fasten the bracket 15 to the door 10, the gap formed at the bifurcation 47 is squeezed together to tightly grip the outer tube 17 of the closer completing the assembly of the outer tube 17 to the bracket 15 which then acts as the end termination for the outer tube 17 of the closer mechanism.
The inner tube of the closer mechanism is closed or sealed in its left-hand end (as viewed in FIGS. 2 and 3) by a plug terminating in a flat latch engaging member 60 which has an elongated slot 61 formed through it. As seen most clearly in FIG. 4, the slot 61 in the member 60 is aligned with the holes 30 and 31 in the legs 26 and 27 when the door 10 is closed. The interconnection of the inner tube 16 and the outer tube 17 is essentially the same as in the above-mentioned U.S. Pat. No. 3,278,979 and is accomplished by means of a tension spring 63. This spring is attached at one end by a threaded retainer 64 to a plug 65 which closes the opposite end (the right-hand end as viewed in FIGS. 2 and 3) of the outer tube 17. The other end of the spring 63 extends through the inside of the hollow inner tube 16 and attaches to the end of the latch engaging member 60 which extends into the tube 16, as shown most clearly in FIG. 3. Thus, it is apparent that the tension spring 63 acts to close or collapse together the telescoping tubes 16 and 17. Adjustments of the tension of the spring 63 are effected by means of the threaded retainer 64 which extends through the cap (plug) 65 as shown in FIG. 3. Thus, the spring 63 may be tightened or loosened by use of a screw driver to rotate the threaded member 64 to change the effective length of the member 64 within the end of the tube 17.
A deformable suction washer 70, which may be of the type used in hand operated air pumps or the like, is attached to the right-hand end of the tube 16 inside the tube 17. The suction washer 70 is made of a generally deformable but resilient material such as rubber, leather, plastic or the like. The outer surface of the washer 70 slidingly engages the inner side of the outer tube 17. Since the washer is yieldable, air freely passes when the telescoped tubes 16 and 17 are opened or extended, but air pressure created as the tubes close to their collapsed position causes the suction washer to expand and effectively seal the space between the inner and outer tubes 16 and 17.
A bleeder valve 71 is positioned in communication with the interior of the outer tube 17 at the end closed by the plug 65. The bleeder valve 71 also could be placed in the assembly holding the washer 70 if desired. As illustrated in FIG. 3, however, the bleeder valve extends through the plug 65 and includes an aperture 73 closed by a threaded screw member 75. A slot or a groove in the threaded portion of the screw member 75 permits air to escape through the aperture 73 at the desired rate. By adjusting the screw 75, the rate of closing of the apparatus may be controlled by controlling the rate at which air is permitted to escape through the bleeder valve 71. The operation of such valves is conventional, and the valve may take on configurations other than the one specifically shown in FIG. 3.
When the brackets 13 and 15 are attached to the door frame and the door, respectively, as described above and as shown in FIG. 1, the locking bar 32 may be used to control the different modes of operation of the apparatus. When the door 10 is closed to align all of the parts of the brackets 13 and 15 and to align the latch engaging member 60 with the holes 30 and 31 in the legs 26 and 27 as shown in FIG. 4, any one of three different modes of operation of the sliding door may be effected. If the door is closed as described and the locking bar 32 is inserted all the way through to terminate in the leg 21 by placing the detent 34 in alignment with the follower 37, all of the parts are locked together. In this position, the door cannot be opened since the tube 17 is firmly locked in the bracket 15 which in turn is locked to the bracket 13 by means of the locking bar 32 passing through all three legs of the locking bar 13 as through the key slot 50 in the bracket 15. This is an effective slide bolt or dead bolt lock of the sliding door and prevents its opening.
Next, assume that the door 10 is to be unlocked and is to be operated using the action of the closer comprised of the inner and outer tubes 16 and 17 to automatically close the door, at a rate controlled by the setting of the bleeder valve 71, each time the door is opened. To accomplish this, the locking bar 32 is withdrawn to its second position causing the detent 35 to be aligned with the follower 37. In this position, the extension on the bracket 15 is permitted to freely pass in and out of the opening between the legs 21 and 26 of the bracket 13. When the locking bar 32, however, is moved to this position with the door closed, it extends through the slot 61 in the latch engaging member 60 to hold the latch engaging member in place. Thus, when the door is moved to the right as viewed in FIGS. 2, 3 and 4 (or to the left as viewed in FIG. 1) the end of the inner tube 16 is held in place by the locking bar 32 to cause the relative extension of the closure member as illustrated in FIG. 1 against the bias of the tension spring 63, stretching the tension spring. When the door is released, the tension spring pulls the two tubes 16 and 17 together to return it to the closed position illustrated in dotted lines in FIG. 4.
The third mode of operation of the sliding door 10 using the locking mechanism illustrated in FIGS. 2 and 4 is with the locking bar 32 in its lowermost position. In this position, the detent 36 is aligned with the follower 37; and the spaces between all of the three legs 21, 26 and 27 of the bracket 13 are clear of or free of the locking bar 32. In this position, there is nothing to hold the latch engaging member 60 in place when the door is opened; so that the latch engaging member 60 moves right along with the movement of the bracket 15 when the door is open. Thus, the door functions in its conventional fashion as if the closer member were not present. In this mode of operation the door can be left open in any partially open or fully open position, without the necessity of propping it open with a chair or using some other type of apparatus or device to present the closer member from reclosing the door.
At any time that resumption of the operation of the closer member is desired, the door merely is fully closed, the locking bar 32 is moved upwardly as viewed in FIG. 4 to its second position to pass through the slot 61 in the latch engaging member 60, and operation of the door under the control of the closer mechanism once more is resumed. Similarly, a return to the fully locked position is accomplished in a similar manner by closing the door and then inserting the locking bar 32 to its uppermost vertical position, it then can be rotated in either direction (depending upon whether the bracket 13 is mounted for a left-hand or right-hand closing door) into one of the two slots which then retain the end of the handle 44 and prevent the bar 32 from accidentally dropping downwardly. The detent 37 should be sufficient to accomplish this purpose but the additional security provided by the slots 80 and 81 mitigates against any possible accidental dropping of the bar 32.
The foregoing description has been limited to a preferred embodiment of the invention which, however, is considered to be merely illustrative of the principles of the invention and not limiting of the true scope of the invention. Various modifications and equivalent applications of the concepts of this invention will occur to those skilled in the art without departing from the true scope of the invention as set forth in the following claims. | A closure for sliding arcadia doors utilizes a pair of telescoping tubes biased to their telescoped or closed position by an internal interconnecting tension spring and employs a pneumatic system and a bleeder valve to control the rate of closing or telescoping of the tubes once they have been opened against the bias of the tension spring. A locking mechanism uses a locking bar and a pair of brackets, one connected to the corner of the door frame and the other mounted on the door for movement with it, (1) to lock the door closed, (2) permit the door to be opened using the door closer so that it is automatically closed by the closer, or (3) to permit the door to be used in its normal manner as if the door closer was not present. | 4 |
BACKGROUND OF THE INVENTION
Substituted morpholines are commercially available and widely used as dispersing agents for waxes and the like. These morpholines are easily prepared from substituted diethanolamines by closing the ring.
Substituted morpholin-2-ones ("2-morpholones") on the other hand, are relatively uncommon compounds known to be useful in pharmaceutical preparations, and not easily prepared. Such 2-morpholones are conventionally prepared as described in Heterocyclic Compounds, Vol 6, by Robert C. Elderfield in the chapter entitled "The Monocyclic Oxazines", John Wiley & Sons, Inc. New York (1957).
More recently a mixture of 2-morpholone dimers was produced by irradiation of 5,6-dihydro-3,5,5-trimethyl-1,4-oxazin-2-one in 2-propanol solvent 15° C. (see "An Unusually Weak Carbon-Carbon Single Bond" by Koch, T. H., Olesen, J. A., and DeNiro, J. in J. Am. Chem. Soc. 97:25, 7285-80, 1979). The mixed dimers were found to be thermally unstable in solution, and in the presence of oxygen the dimer was rapidly oxidized to 5,6-dihydro-3,5,5-trimethyl-1,4-oxazin-2-one; but prolonged heating in the absence of oxygen gave a mixture of the foregoing oxazine and 3,5,5-trimethylmorpholin-2-one ("morpholone"). The morpholone so formed must, as a result, have only one substituent on the C atom in the "3" position (C 3 ) of the ring. Though there are two alkyl substituents on the C 5 atom of the ring, it will be realized that the substituents on this C 5 atom are necessarily lower alkyl. Thus the prior art monomer is a tri-substituted morpholone with only a single substituent on the C 3 atom, and it may not be tetra-substituted with alkyl substituents.
Still more recently, a 5,5-dimethyl-3-phenyl-2-morpholone was prepared which was somewhat unstable and existed in equilibrium with a ring-opened product identified as methyl-2-phenyl-2-(1,1-dimethyl-2-hydroxyethyl)aminoacetate (see "Electron-Transfer Chemistry of the Merostabilized 3,5,5-Trimethyl-2-morpholinon-3-yl Radical" by Burns, J. M., Wharry, D. L. and Koch, T. H., J. Am. Chem. Soc., 103, 849-856, 1981).
Research probing the reactions of the dimers resulted in the knowledge that a mixture of meso and dl dimers heated with 2,2'-azobis(2-methylpropionitrile) produced [2'-(2'-cyanopropyl)]-3,5,5-trimethylmorpholin-2-one. This cyanoalkyl substituted-trimethylmorpholone and the phenyl-substituted-trimethylmorpholone are the only tetra-substituted 2-morpholones known. The substituents on the N-adjacent C atoms cannot be changed because of the recognized relative instability of the lactone ring. For example, it has been found that this ring can neither be reduced nor oxidized without opening it. Thus, I know neither of any tri- or tetra-substituted morpholines which maybe derived from known 2-morpholones, nor of any 2-morpholones which can be derived by replacement of the cyanoalkyl or phenyl substituents on the C 3 atom by another substituent without disrupting the lactone ring. Nor do I know of any method for preparing a C 3 -cyanoalkyl-substituted-2-morpholone or C 3 -phenyl-substituted-2-morpholone, with other than lower alkyl substituents on the C 5 atom of the lactone ring.
Stated differently, it was not heretofore known how polysubstituted compounds may be prepared which have either (a) three substituents which are not lower alkyl, or, (b) three substituents, one of which on C 3 is phenyl or cyanoalkyl, and at least one of the remaining two substituents on the other N-adjacent C atom is not alkyl, or, (c) four substituents all of which may be alkyl, on the (combined) N-adjacent C atoms. The term "polysubstituted" is specifically used in this specification to connote that in the claimed compounds of this invention, a total of three or more substituents is necessarily present on the two N-adjacent C atoms, combined; and, two substituents, which may be cyclized, are always present on the C 3 atom when the compound is a 2-morpholone. In this sense, it will be recognized that if each of the substituents on the one N-adjacent C atom are cyclic substituents, and the substituents on the other N-adjacent C atom are not, then there are a total of four substituents; there are also four substituents if the two substituents on each N-adjacent C atom are together cyclized.
The problem with preparing polysubstituted 2-morpholones carries over to the preparation of polysubstituted morpholines. For example, it is known that reductive alkylation of HOCH 2 C(CH 3 ) 2 NH 2 with CH 3 COCH 2 OH yields [(HOCH 2 C(CH 3 ) 2 ]NH[CH(CH 3 )CH 2 OH] which upon cyclization by heating with conc H 2 SO 4 produces 3,5,5-trimethylmorpholine (see 112872h Chem. Abstr. Vol 71, pg 374, 1979), but this approach cannot produce a trimethyl-2-morpholone.
The key to providing three or more substituents on the combined N-adjacent C atoms, is to provide the polysubstituents on the C atoms before the ring is closed. Only a few such polysubstituted compounds are known. In these known compounds, only specific substituents may be present because of the manner in which the compounds are necessarily prepared. Such compounds are3-[2'-(2'-cyanopropyl)]-3,5,5-trimethylmorpholin-2-one, prepared as described in the Koch et al. articles, supra; and, 5,5-dimethyl-3-phenyl-2-morpholinone, prepared as described in the Burns et al article, supra. Though sodium hydroxyethylaminoacetate is easily prepared, and two substituents may be made on one or the other N-adjacent C atom, or, one substituent may be made on one and also (one) on the other N-adjacent C atom, polysubstituted hydroxyethylaminoacetates ("HEAA" for brevity) having three or more substituents have not been known or made because of the steric hindrance problems, inter alia. Further, though polysubstituted aminodiols such as [HOCH 2 C(CH 3 ) 2 ]NH[CH(CH 3 )CH 2 OH] are known, I know of no apparently operable method for converting such aminodiols to N-hydroxyalkylamino acids. As a result, tri-substituted or tetra-substituted N-adjacent C atoms of an alkali metal hydroxyethylaminoacetate are not known.
Hindered amines, to which general class the compounds of this invention belong, are known to have utility as u-v light stabilizers in synthetic resins subject to actinic radiation. However, not all hindered amines are effective stabilizers against u-v light degradation in normally solid polymers. Some hindered amines are thermally unstable at as low as 100° C. which precludes their use in any organic material which is processed at or above that temperature. Further, particularly with polysubstituted heterocyclic ring compounds, N atoms in the ring are known to have a beneficial effect but there is no more reason to expect that a polysubstituted morpholone might be effective than there is to believe that a polysubstituted thiomorpholine might be effective. More particularly, it was known that dimers of 5,6-dihydro-3,5,5-trimethyl-1,4-oxazin-2-one are photoreductive and thermally unstable in solution when heated to 80° C., and that in solution, these dimers exist in equilibrium with a radical at room temperature (Koch et al, supra). Therefore, it was quite surprising that a polysubstituted 2-morpholone or a polysubstituted related compound, would provide excellent u-v light stability.
Because of the unpredictability of the effectiveness of various hindered amines solely based on their (hindered) structure, much effort has been expended to synthesize hindered amines which must then be tested for possible utility as u-v light stabilizers. One of the synthesis is described in an article titled "Hindered Amines. Novel Synthesis of 1,3,3,5,5-Pentasubstituted 2-Piperazinones" by John T. Lai in J. Org. Chem. 45, 754 (1980). The concept of retaining the "2-keto" ring structure of a heterocyclic ring containing at least one N atom was the basis upon which the search for effective 2-morpholones was initiated. The necessity of providing more than two substituents on the N-adjacent C atoms spurred the discovery of the application of a "ketoform synthesis" to solve the problem. This invention derives from further research in the field of the synthesis of hindered amines, and an evaluation of their effectiveness as u-v light stabilizers.
Hindered amines of the prior art are generally complex compounds not prepared with notable ease, and their properties, particularly their compatibility in various synthetic resins, is difficult to predict. Apparently small differences in structure, result in large differences in performance. Prolonged efforts to provide simpler compounds which are relatively easily prepared, have resulted in the 2-keto-1,4-diazacycloalkanes and the 2-keto-1,5-diazacycloalkanes disclosed in U.S. Pat. Nos. 4,190,571 and 4,207,228.
The present invention is particularly directed to (a) novel polysubstituted alkali metal hydroxyethylaminoacetates, (b) a novel synthesis for a polysubstituted alkali metal hydroxyethylaminoacetate, (c) novel compositions in which a polysubstituted alkali metal hydroxyethylaminoacetate is incorporated, (d) novel polysubstituted 2-morpholones, (e) a novel synthesis for polysubstituted 2-morpholones, (f) novel compositions stabilized against u-v light degradation by the presence of a stabilizing amount of the 2-morpholones, (g) novel polysubstituted aminodiols, (h) novel compositions stabilized against u-v light degradation by the presence of a small but effective amount of a polysubstituted aminodiol, (i) novel polysubstituted monoaza crown ethers, (j) synthesis of polysubstituted monoaza crown ethers, (k) novel compositions stabilized against u-v light degradation by the presence of an effective amount a polysubstituted monoaza crown ether, (l) polysubstituted morpholine, (m) synthesis of polysubstituted morpholine by cyclization of an aminodiol with an alkanesulfonic acid, (n) novel compositions stabilized against u-v light degradation by the presence therein of an effective amount of a polysubstituted morpholine, (o) novel polysubstituted aminodiethers, and (p) novel compositions stabilized by the presence therein of an effective amount of a polysubstituted aminodiether.
The synthesis of the novel stabilizers of this invention is facilitated by the peculiar action of certain onium salts in an aqueous alkaline medium, which action facilitates the interaction of an amine nucleophilic agent such as a primary or secondary amine, with chloroform or other trichloromethide generating agent, and a ketone or aldehyde. The organic onium salts of nitrogen, and phosphorus are well known. They are ionized in aqueous solutions to form stable cations. Certain onium salts have provided the basis for phase transfer catalysis in a wide variety of reactions, a recent and comprehensive review of which is contained in Angewandte Chemie, International Edition in English, 16 493-558 (August 1977). Discussed therein are various anion transfer reactions where the onium salt exchanges its original anion for other anions in the aqueous phase. These ion pairs can then enter a water immiscible, organic liquid phase, making it possible to carry out chemistry there with the transported anion, including OH - ions. Many reactions involving water immiscible solutions of various simple organic molecules have been described. Though the use of phase transfer catalysts facilitate the cyclization of an appropriately sterically hindered branched chain amine having proximate primary and secondary amine groups amongst plural amine groups in the chain, the reaction has also been found to proceed, though relatively slowly, by simply using a large excess of the ketone or aromatic aldehyde either of which is the the essential carbonyl containing compound which contributes the carbonyl group to the 2-position of the diazacycloalkane ring.
A phase transfer catalyzed reaction known as the "ketoform reaction" is disclosed in U.S. Pat. No. 4,167,512, which proceeds by virtue of a phase transfer catalyzed reaction mechanism in which an amine, a haloform and a carbonyl containing ("carbonyl") compound are separate reactants. This reaction is illustrated in one particular example by the reaction of a N,N'-alkyl substituted ethylene diamine with acetone and chloroform; and, in another example, with o-phenylene diamine reacted with cyclohexanone and chloroform. The reaction product in each example is a 2-keto-1,4-diazacycloalkane.
Though both ketones and aldehydes are taught as being effective reactants in the ketoform reaction, it has now been discovered that only ketones and benzaldehyde are effective in the formation of HEAA. Accordingly, my present invention is a particular adaptation of the ketoform reaction to the preparation of alkali metal HEAA, and several successor compounds derived therefrom, including 2-morpholones, aminodiols, monoaza crown ethers, and morpholines, all of which are polysubstituted, and are collectively referred to herein as "HEAA compounds" for brevity.
SUMMARY OF THE INVENTION
An essentially single stage reaction has been discovered in which a disubstituted ethanolamine, that is, a 2,2'-disubstituted-2-aminoethanol, may be reacted with a haloform and a carbonyl containing compound selected from the group consisting of monoketones and an aromatic monoaldehyde (araldehyde) having from 7 to about 9 carbon atoms, in the presence of an alkali metal hydroxide, and optionally in the presence of a phase transfer catalyst, to produce an alkali metal hydroxyethylaminoacetate ("HEAA") which has N-adjacent C atoms on which there are a total of at least three substituents (hence "polysubstituted"), and one or both pairs of substituents on each N-adjacent C atom may be cyclized.
It has further been discovered that a polysubstituted alkali metal HEAA may be cyclized by the action of a strong acid, for example concentrated HCl, to produce a 2-morpholone hydrochloride which is characterized by having a total of at least three substituents on the N-adjacent C atoms of the ring. By reaction with triethylamine, or other base, a polysubstituted 2-morpholone is produced. Novel polysubstituted 2-morpholones are produced in which the C 3 position is disubstituted from a wide choice of substituents. If the C 3 position is monosubstituted with phenyl then the C 5 position is substituted with at least one substituent which is not lower alkyl; if the C 3 position is disubstituted and one of the two substituents is cyanoalkyl, then the C 5 position is substituted with at least one substituent which is not lower alkyl.
It has still further been discovered that the polysubstituted 2-morpholones so produced may be reduced by reaction with LiAlH 4 , diborane, or H 2 under pressure in the presence of Raney's nickel catalyst, to a polysubstituted aminodiol.
It has also been discovered that the aminodiol so produced may be cyclized with an alkane sulfonic acid to yield a polysubstituted morpholine which could not otherwise have been made, and can now be made only by this cyclization reaction.
It has also further been discovered that the aminodiol so produced may be conventionally alkylated to produce diethers with polysubstituted N-adjacent C atoms. If the aminodiol is reacted with a polyalkyleneglycol ditosylate, a polysubstituted crown ether is produced with plural polyalkylene groups.
It is therefore a general object of this invention to provide novel polysubstituted alkali metal hydroxyethylaminoacetates ("HEAA"), and novel compounds related thereto, or derived therefrom, all of which are collectively referred to herein as "HEAA compounds"; to provide processes for producing the novel compounds; and, to provide novel compositions in which a small but effective amount of one or more of the HEAA compounds is incorporated, optionally in addition with antioxidant synergists, pigments, and other known compounding ingredients, in amounts sufficient to produce desirable stabilization against degradation in a wide variety of organic materials.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
The polysubstituted structure of the various stabilizer compounds prepared by the syntheses described herein, is derived by virtue of an adaptation of the ketoform synthesis. This adaptation permits the preparation of a polysubstituted HEAA without the formation of isocyanides. As is well known, primary amines react with chloroform in the presence of NaOH in the carbylamine reaction which is a delicate test for the presence of a primary amine because of the powerful odor of the ioscyanides formed. No powerful odor of isocyanide is detected in the adaptation of the ketoform reaction as used in this invention.
The HEAA is preferably tetra-substituted, though tri-substituted HEAA also have good u-v stabilization effects in transparent, translucent or lightly colored synthetic resins. Despite the seemingly simple structure of alkali metal HEAA which have at least three substituents on the N-adjacent carbon atoms, these HEAA to my knowledge, can be prepared by no other method than that described hereinbelow.
The structure of an alkali metal HEAA is as follows: ##STR1## wherein, R 1 , R 2 , R 3 and R 4 are independently selected from the group consisting of hydrogen, aryl, alkyl having from 1 to about 24 carbon atoms, cycloalkyl having from 5 to about 7 carbon atoms, aralkyl having from 7 to about 20 carbon atoms, cyanoalkyl having from 2 to about 12 carbon atoms, ether having from 4 to about 18 carbon atoms, and hydroxyalkyl having from 1 to about 18 carbon atoms;
R 1 and R 2 together, or R 3 and R 4 together, or each pair, may be cyclized forming a ring having from about 5 to about 8 carbon atoms;
except that not more than one of R 1 , R 2 , R 3 or R 4 may be hydrogen, and no more than three of R 1 , R 2 , R 3 and R 4 may be cyclic;
R 5 is selected from hydrogen, oxygen, hydroxyl and alkyl having from 1 to about 24 carbon atoms; and,
M represents an alkali metal.
Process for preparing an alkali metal HEAA
The starting material is a 2,2'-substituted-2-amino-ethanol represented by the following structure: ##STR2## wherein R 1 and R 2 have the same connotation as hereinabove, and R 1 and R 2 may together be cyclized forming a ring having from about 5 to about 8 carbon atoms.
As will presently be evident, a wide range of substituents may be made without undue difficulty, and the choice of substituents in large part, determines the properties of the compound as a u-v stabilizer. This aminoethanol may be only mono-substituted, depending upon the choice of a ketone as a reactant in the reaction to be described hereinbelow, but best results are obtained when the aminoethanol is di-substituted, which includes the case where R 1 and R 2 are cyclized. Since the aminoethanol is a primary amine it will be apparent that any substituent desired on the N atom will have to be made after the formation of the polysubstituted alkali metal hydroxyethylaminoacetate ("HEAA") as set forth hereunder.
This aminoethanol is reacted with (i) at least one molar equivalent of a haloform selected from the group consisting of chloroform and bromoform, and (ii) at least one molar equivalent of a carbonyl containing compound selected from the group consisting of monoketones and an aromatic monoaldehyde ("araldehyde") which may be ring substituted having from 7 to about 9 carbon atoms, optionally (iii) in the presence of a phase transfer catalyst, and, necessarily with (iv) at least one molar equivalent of an alkali metal hydroxide so as to form the alkali metal HEAA. The preferred temperature of the reaction with a ketone is in the range from about -10° C. to about 30° C. at ambient pressure, and from about 10° C. to about 60° C. with an araldehyde. Some reactions may be preferably carried out under elevated pressure, and others under vacuum, but in general, pressure plays only its expected role in the progress of the reaction.
The HEAA compounds of this invention are hindered amines and undergo the expected reactions which hindered amines are known to undergo. For example, the hydrogen on the N atom may be replaced with an alkyl group having from 1 to about 24 carbon atoms, by conventional alkylation; or, the H may be replaced by oxygen by reaction of the HEAA with metachloroperbenzoic acid; in turn, it will be appreciated, that the alkyl group or oxygen so introduced on the N atom, may be further reacted, conventionally, to give additional substituents.
Process for preparing polysubstituted 2-morpholones
The alkali metal HEAA prepared as described hereinabove may be cyclized with a cyclization agent to yield a 2-morpholone which retains the substituents on the N-adjacent atoms. The polysubstituted 2-morpholone has the following structure: ##STR3## wherein, R 1 , R 2 , R 3 and R 4 are independently selected from the group consisting of aryl, alkyl having from 1 to about 24 carbon atoms, cycloalkyl having from 5 to about 7 carbon atoms, aralkyl having from 7 to about 20 carbon atoms, cyanoalkyl having from 2 to about 12 carbon atoms, ether having from 4 to about 18 carbon atoms, and hydroxyalkyl having from 1 to about 18 carbon atoms;
R 1 and R 2 together, or R 3 and R 4 together, or each pair, may be cyclized forming a ring having from about 5 to about 8 carbon atoms; and,
R 5 is selected from hydrogen, oxygen and alkyl having from 1 to about 24 carbon atoms, and hydroxyl;
except that not more than one of R 1 , R 2 , R 3 or R 4 may be hydrogen; and no more than three of R 1 , R 2 , R 3 and R 4 may be cyclic; further, if one of R 3 and R 4 is H or lower alkyl having from 1 to about 6 carbon atoms and the other is phenyl or cyanoalkyl, then at least one of R 1 and R 2 is not alkyl.
Cyclization is preferably effected by contacting the alkali metal HEAA with strong acid, for example concentrated HCl. The 2-morpholone hydrochloride so formed may then be reacted with triethylamine to remove the HCl and form the 2-morpholone. The temperature at which the reaction is carried out may be in the range from from about -10° C. to about 100° C.
Process for preparing polysubstituted aminodiols
The polysubstituted 2-morpholones prepared as described hereinabove may be reduced with a suitable reducing agent to yield a polysubstituted aminodiol having the structure: ##STR4## wherein, R 1 , R 2 , R 3 and R 4 are independently selected from the group consisting of aryl, alkyl having from 1 to about 24 carbon atoms, cycloalkyl having from 5 to about 7 carbon atoms, aralkyl having from 7 to about 20 carbon atoms, cyanoalkyl having from 2 to about 12 carbon atoms, ether having from 4 to about 18 carbon atoms, and hydroxyalkyl having from 1 to about 18 carbon atoms;
R 1 and R 2 together, or R 3 and R 4 together, or each pair, may be cyclized forming a ring having from about 5 to about 8 carbon atoms; and,
R 5 is selected from hydrogen, oxygen, hydroxyl and alkyl having from 1 to about 24 carbon atoms;
except that not more than one of R 1 , R 2 , R 3 or R 4 may be hydrogen; and no more than three of R 1 , R 2 , R 3 and R 4 may be cyclic.
The reduction of the polysubstituted 2-morpholone may be effected by any conventional reaction such as reduction with diborane, or LiAlH 4 , or more preferably, with H 2 under pressure in the presence of a Raney's nickel catalyst, any of which reactions result in opening of the lactone ring rather than formation of the morpholine. If reduced with LiAlH 4 the reactants are dissolved in THF and refluxed for several hours. After cooling, the reaction mixture is neutralized with dilute NaOH solution to yield the aminodiol which is normally solid.
Process for preparing polysubstituted monoaza crown ethers
The polysubstituted aminodiol prepared as described hereinabove may be cyclized so as to include a polyalkylene oxide bridge, by reaction with a polyalkylenediol with terminal leaving groups, so as to yield a monoaza crown ether. This reaction is quite unexpected because it occurs despite the hindrance of the substituents on the N-adjacent atom of the aminodiol. The monoaza crown ether formed upon cyclization is represented by the structure: ##STR5## wherein, R 1 , R 2 , R 3 and R 4 are independently selected from the group consisting of aryl, alkyl having from 1 to about 24 carbon atoms, cycloalkyl having from 5 to about 7 carbon atoms, aralkyl having from 7 to about 20 carbon atoms, cyanoalkyl having from 2 to about 12 carbon atoms, ether having from 4 to about 18 carbon atoms, and hydroxyalkyl having from 2 to about 18 carbon atoms;
R 1 and R 2 together, or R 3 and R 4 together, or each pair, may be cyclized forming a ring having from about 5 to about 8 carbon atoms; and,
R 5 is selected from hydrogen, oxygen and alkyl having from 1 to about 24 carbon atoms, and hydroxyl;
except that not more than one of R 1 , R 2 , R 3 or R 4 may be hydrogen; and no more than three of R 1 , R 2 , R 3 and R 4 may be cyclic; and, x and n are integers in the range from 2 to 4.
The polyalkylene oxide bridge is preferably introduced into the monoaza crown ether ring by tosylation with a ditosylglycol. Though there may be three methylene groups, most preferred are two, that is, a polyethylene oxide bridge.
Process for preparing polysubstituted morpholines
The aminodiol obtained as described hereinabove may be cyclized by reaction with an alkane sulfonic acid to yield a polysubstituted morpholine having the structure: ##STR6## wherein, R 1 , R 2 , R 3 and R 4 are independently selected from the group consisting of aryl, alkyl having from 1 to about 24 carbon atoms, cycloalkyl having from 5 to about 7 carbon atoms, aralkyl having from 7 to about 20 carbon atoms, cyanoalkyl having from 2 to about 12 carbon atoms, ether having from 4 to about 18 carbon atoms, and hydroxyalkyl having from 2 to about 18 carbon atoms;
R 1 and R 2 together, or R 3 and R 4 together, or each pair, may be cyclized forming a ring having from about 5 to about 8 carbon atoms; and,
R 5 is selected from hydrogen, oxygen and alkyl having from 1 to about 24 carbon atoms, and hydroxyl;
except that not more than one of R 1 , R 2 , R 3 or R 4 maybe hydrogen; and no more than three of R 1 , R 2 , R 3 and R 4 may be cyclic.
Only an alkane sulfonic acid is effective to cyclize the aminodiol, and lower alkane sulfonic acids having from 1 to about 5 carbon atoms are preferred. Most preferred is methane sulfonic acid which is heated to a temperature in the range from about 100° C. to about 150° C. to cyclize the aminodiol. The reaction occurs over a period of about 10 hr, after which the reaction mixture is cooled down and 10% NaOH is added. Upon working up the mixture to recover the pure polysubstituted morpholine, a colorless oil is usually obtained.
Process for preparing polysubstituted aminodiethers
The aminodiol obtained as described hereinabove may be converted to an aminodiether by reaction with an alkyl iodide or dimethyl sulfate, after first heating the aminodiol to reflux in an aromatic solvent such as toluene, in the presence of a stong base, such as sodium hydride, under an inert atmosphere. The aminodiether obtained may be worked up by adding water, extracting the aqueous solution with toluene, drying the combined toluene solutions with sodium sulfate, and concentrating. The aminodiether is isolated by simple distillation.
The structure of a polysubstituted aminodiether is as follows: ##STR7## wherein, R 1 , R 2 , R 3 and R 4 are independently selected from the group consisting of hydrogen, aryl, alkyl having from 1 to about 24 carbon atoms, cycloalkyl having from 5 to about 7 carbon atoms, aralkyl having from 7 to about 20 carbon atoms, cyanoalkyl having from 2 to about 12 carbon atoms, ether having from 4 to about 18 carbon atoms, and hydroxyalkyl having from 2 to about 18 carbon atoms;
R 1 and R 2 together, or R 3 and R 4 together, or each pair, may be cyclized forming a ring having from about 5 to about 8 carbon atoms;
except that not more than one of R 1 , R 2 , R 3 or R 4 may be hydrogen, and no more than three of R 1 , R 2 , R 3 and R 4 may be cyclic;
R 5 is selected from hydrogen, oxygen and alkyl having from 1 to about 24 carbon atoms;
R 6 and R 7 are independently selected from the group consisting of alkyl having from 1 to about 24 carbon atoms, and aralkyl having from 7 to about 24 carbon atoms.
The polysubstituted HEAA compounds are generally crystalline solids soluble in acetone, diethyl ether, dioxane, tetrahydrofuran, carbon tetrachloride, chloroform, lower primary alcohols having from 1 to about 6 carbon atoms such as methanol, ethanol and propanol, aromatic hydrocarbons such as benzene and toluene, but much less soluble in aliphatic hydrocarbons such as hexane. Some HEAA-derived compounds are oily lightly colored liquids. Many are quite soluble in water and are especially useful when they are to be dispersed in a latex to be stabilized against u-v light degradation. The alkali metal salts range in color from water-white to brown when pure, but when dispersed in an organic material, particularly in polyolefins, polyamides, and polyvinyl aromatics, at a concentration of less than 5 parts per 100 parts by weight of organic material, the color of the HEAA in the composition is not noticeable.
The amount of the stabilizer employed will vary with the particular material to be stabilized and also the polysubstituted HEAA or HEAA-related stabilizer employed. Generally however, for effective u-v light stabilization of most organic materials, an amount of the stabilizer used is in the range from about 0.001 percent to about 10 percent by weight (% by wt) based on the weight of organic material. In typical stabilized compositions the amount of polysubstituted stabilizer used is in the range from about 0.01 to about 5% by wt.
Compositions of this invention are synthetic resinous materials which have been stabilized to combat the deleterious effects of uv light, thermal or oxidative degradation such as are usually evidenced by discoloration and/or embrittlement. These compositions generally benefit from the inclusion of additional, secondary stabilizers to achieve even greater stability against a combination of actinic light, heat and oxygen. Therefore, in conjunction with the stabilizers of this invention, compositions may include stabilizers against degradation by heat and/or oxygen which secondary stabilizers may be present in the range from about 0.1 part to about 10 parts by weight, and preferably from about 0.2 part to about 5 parts by weight per 100 parts by weight of the organic continuous phase. Several types of known UV secondary stabilizers may be used, such as those disclosed in U.S. Pat. Nos. 3,325,448; 3,769,259; 3,920,659; 3,962,255; 3,966,711; 3,971,757; inter alia.
Organic materials which may be stabilized against uv light, thermal and oxidative degradation, include copolymers of butadiene with acrylic acid, alkyl acrylates or methacrylates, polyisoprene, polychloroprene, and the like; polyurethanes; vinyl polymers known as PVC resins such as polyvinyl chloride, copolymers of vinyl chloride with vinylidene chloride, copolymers of vinyl halide with butadiene, styrene, vinyl esters, and the like; polyamides such as those derived from the reaction of hexamethylene diamine with adipic or sebacic acid; epoxy resins such as those obtained from the condensation of epichlorohydrin with bisphenols, and the like; ABS resins, polystyrene, polyacrylonitrile, polymethacrylates, poly-carbonates, varnish, phenol-formaldehyde resins, polyepoxides, polyesters, and polyolefin homo- and copolymers such as polyethylene, polypropylene, ethylene-propylene polymers, ethylene-propylenediene polymers, ethylene-vinyl acetate polymers, and the like. The polysubstituted HEAA compounds can also be used to stabilize mixtures and blends of polymeric materials such as ABS resin blends, PVC and polymethacrylate blends, and blends of polyolefin homopolymers and copolymers such as blends of polypropylene in epdm polymers.
Most particularly substituted HEAA and HEAA-derived compounds of this invention having at least three and preferably four substituents on the N-adjacent C atoms, including of course if the substituents are cyclized, are especially useful as uv-light-stabilizers for synthetic resinous materials which are at least partially permeable to visible light, and particularly for those which are transparent thereto, such as the polyvinylaromatics and polyolefins. It will be recognized that if each of the substituents R 1 and R 2 on the N-adjacent C atom are cyclized, and the R 2 and R 3 substituents of the other N-adjacent C atom are not, then, in the sense used herein, there are still four substituents, as is also the case if the substituents R 3 and R 4 are cyclized.
Many known compounding ingredients may be used along with the substituted PIP-T stabilizers in the compositions. Such ingredients include metal oxides such as zinc, calcium and magnesium oxide, fatty acids such as stearic and lauric acid, and salts thereof such as cadmium, zinc and sodium stearate and lead oleate; fillers such as calcium and magnesium carbonate, calcium and barium sulfates, aluminum silicates, asbestos, and the like; plasticizers and extenders such as dialkyl and diaryl ogranic acids like diisobutyl, diisooctyl, diisodecyl, and dibenzyl oleates, stearates, sebacates, azelates, phthalates, and the like; ASTM type 2 petroleum oils, paraffinic oils, castor oil, tall oil, glycerin, and the like.
Particularly desirable secondary stabilizers are one or more antioxidants used in the range from about 0.1 part to about 20 parts by weight, preferably from about 0.2 part to about 5 parts by weight per 100 parts by weight of the material. Of the types of antioxidants to be used, are phosphite, phosphate, sulfide and phenolic antioxidants, the last being preferred. Most preferred are phenolic antioxidants such as 2,6-di-t-butyl paracresol; 2,2'-methylene-bis-(6-t-butyl-phenol); 2,2'-thiobis-(4-methyl-6-t-butyl-phenol); 2,2'-methylene-bis-(6-t-butyl-4-ethyl-phenol); 4,4'-butylene-bis-(6-t-butyl-m-cresol); 2-(4-hydroxy-3,5-di-t-butylanilino)-4,6-bis-(octylthio)-1,3,5-triazine; hexahydro-1,3,5-tris-(3,5-di-t-butyl-4-hydroxyphenyl)propionyl-s-triazine; hexahydro-1,3,5-tirs-(3,5-di-t-butyl-4-hydroxybenzyl)-isocyanurate; tetrakismethylene-3-(3',5'-di-t-butyl-4'-hydroxyphenyl)propionate methane; and other antioxidant synergists such as distearyl thiodipropionate; dilauryl thiodipropionate; tri(nonylphenyl)phosphite; tin thioglycolate; and particularly commercially available antioxidants such as Goodrite® 3114, and 3125, Irganox 1010, 1035, 1076 and 1093. Other ingredients such as pigments, tackifiers, flame retardants, fungicides, and the like may also be added.
The polysubstituted HEAA stabilizers, and the other compounding ingredients if used, can be admixed with organic materials using known mixing techniques and equipment such as internal mixing kettles, a Banbury mixer, a Henschel mixer, a two-roll mill, an extruder mixer, or other standard equipment, to yield a composition which may be extruded, pressed, blowmolded or the like into film, fiber or shaped articles. Usual mixing times and temperatures can be employed which may be determined with a little trial and error for any particular compositions. The objective is to obtain intimate and uniform mixing of the components. A favorable mixing procedure to use when adding a polysubstituted HEAA to an organic material is either to dissolve or suspend the compound in a liquid such as hexane or benzene before adding it, or to add the HEAA directly to the polymeric organic material whether the HEAA is in the form of a powder or oil, or to extruder-mix the HEAA and the polymeric material prior to forming the product.
The u-v stability of a particular composition containing a polymeric material and a polysubstituted HEAA can be evalutated by exposing a prepared sample of the composition to Xenon or carbon arc light in a Weather-O-meter operating at a temperature, for example, about 140° F. (60° C.). Degradation of the sample can be followed by periodically measuring tensile strength left, and the hydroperoxide absorption band at 3460 cm -1 or carbonyl absorption band at 1720 cm -1 using an IR spectrophotometer. The rapid formation of carbonyl indicates failure of the sample. The test procedure is well known, and is published in the text Photodegradation, Photo-oxidation and Photostabilization of Polymers by Ranby and Rabek, John Wiley & Sons, New York, N.Y. (1975), at pages 129 et seq., and is disclosed in U.S. Pat. No. 3,909,493. Failure of the sample is also checked by visual signs of cracking when the sample is bent 180°.
Samples of the compositions can also be checked for oxidative and thermal stability by measuring the time to discoloration and/or embrittlement of the sample after aging in an air circulating oven at 140° C., and other standard ASTM tests.
The following Table I sets forth data obtained in tests conducted with 2 mil thickness samples of polyproylene. The blank and each sample includes 0.05 parts per hundred parts of resin (`phr`) of Goodrite* 3125 antioxidant, and the amount of stabilizer used in each sample is stated. Oven aging is done continuously at 125° C. in the standard test procedure, and the Weather-O-Meter tests give the number of hours after which a sample loses 50% of its tensile strength. Test compositions of this invention were removed from the oven after having withstood 33 days, and were removed from the Weather-O-Meter after having withstood more than 2000 hr without losing 50% of their tensile strength. The results documented simply indicate that the samples withstood more than 33 days of oven aging, and more than 2000 Weather-O-Meter exposure. Chimasorb® 944 is a commercially available polytriazine having piperidine substituents disclosed in U.S. Pat. No. 4,086,204. Cyasorb® 531 is also a commercially available stablizer (from American Cyanamid Co.) having a benzophenone structure.
TABLE I__________________________________________________________________________ Amount Oven aging Failure*Ex. Stabilizer used (phr) (days) (hr)__________________________________________________________________________1 Blank 0 25 8702 Cyasorb 531 0.1 25 17603 Chimasorb 944 0.1 25 18604 sodium tetramethyl-hydroxyethylamino 0.1 33 >2000 acetate ("4M-HEAA")5 3,3,5,5-tetramethyl-2-morpholone 0.1 33 >20006 3,3-pentamethylene-5,5-dimethyl-2 0.1 33 >2000 morpholone7 3-ethyl-3,5,5-trimethyl-2-morpholone 0.1 33 >20008 di-(1-hydroxy-2-methyl-2-propyl)amine 0.1 33 >20009 3,3,5,5-tetramethyl-morpholine 0.1 33 >2000__________________________________________________________________________ *tensil strength was about 50% of original
EXAMPLE 1
A. Preparation of sodium tetramethyl-hydroxyethylaminoacetate ("4M-HEAA") having the structure: ##STR8##
2-amino-2-methyl--propanol (0.6 mole), chloroform (0.8 mole), acetone (2.4 mole) and benzyltriethylammonium chloride (0.018 mole) are placed in a three-necked flask cooled in a circulating ice bath so that the temperature is maintained in the range from about 0°-5° C. Aqueous sodium hydroxide (50% solution) is added dropwise into the contents of the flask while they are stirred. It is preferred to add at least four moles of NaOH for each mole of 2-amino-2-methyl-1-propanol, and a substantial excess over four equivalents is best. Also, in excess of one equivalent of chloroform is used, and nearly two equivalents is better. The phase transfer catalyst may be dispensed with in some instances if a very large excess of ketone is used as a reactant.
Stirring is continued overnight and the reaction mixture is filtered. The solid recovered is a mixture of 4M-HEAA and NaCl, but some of each may still be present in the filtrate. The organic phase is separated from the aqueous phase of the filtrate, and the ketone is recovered from the organic phase. If there is any 4M-HEAA in either the organic or aqueous phases, it may be recovered therefrom in any conventional manner. The solid is rinsed with methylene chloride to dissolve remaining organic phase on the solids which are then stirred into 300 ml methanol in which the 4M-HEAA dissolves but the NaCl does not. Crude 4M-HEAA is recovered from the methanol as a solid. Upon analysis, it is confirmed that the solid obtained is sodium tetramethyl-hydroxyethylaminoacetate.
The compound 4M-HEAA is found to have excellent stabilization properties against u-v light degradation as is evident from the test results when it is incorporated in polypropylene, which results are set forth in Table I hereinbefore.
B. Preparation of sodium 2-[2-methyl-1-hydroxy-2-propylamino]-2-butanoate:
In a manner analogous to that described in example 1A hereinabove, 2-butanone is substituted for acetone, and the reaction similarly carried out. Analysis of the product confirms its identification hereinabove.
C. Preparation of sodium 2-[2-methyl-1-hydroxy-2-propylamino]-2-cyclohexyl carboxylate having the following structure: ##STR9##
In a manner analogous to that described in example 1A hereinabove, cyclohexanone is substituted for acetone, and the reaction similarly carried out. The product obtained is identified as one having the structure written hereinabove.
EXAMPLE 2
A. Preparation of 3,3,5,5-tetramethyl-2-morpholone having the structure: ##STR10##
The crude 4M-HEAA obtained in example 1A hereinabove was refluxed with concentrated HCl (500 ml) for 15 hr and then the HCl is removed in a rotary evaporator, to yield a solid 2-morpholone-hydrochloride. Since the 2-morpholone-hydrochloride still contains small amounts of water, toluene (600 ml) is added and the mixture was refluxed with a Dean-Stark trap to remove all the water. Thereafter, triethylamine (0.9 mole) was added and the mixture refluxed under argon for 10 hr to remove the HCl attached to the 2-morpholone so as to form the compound having the above-identified structure which compound is recovered in better than 75% yield as a colorless oil. From the results set forth in Table I hereinbefore it is evident that the oil has excellent u-v light stabilization characteristics.
B. Preparation of 3-ethyl-3,5,5-trimethyl-2-morpholone:
In a manner analogous to that described in example 2A hereinabove, the sodium 2-[2-methyl-1-hydroxy-2-propylamino]-2-butanoate prepared in example 1B is converted with about 75% yield to a pale oily liquid which, upon analysis, is confirmed as having the structure written immediately hereinabove.
C. Preparation of 3,3-pentamethylene-5,5-dimethyl-2-morpholone having the structure: ##STR11##
In a manner analogous to that described in example 2A hereinabove, the sodium 2-[2-methyl-1-hydroxy-2-propylamino]-2-cyclohexyl carboxylate prepared in example 1C is converted with about 75% yield to a water-white oily liquid which upon analysis, is found to have the structure written immediately hereinabove.
EXAMPLE 3
A Preparation of di-(1-hydroxy-2-methyl-2-propyl)amine having the structure: ##STR12##
0.2 mole of tetramethyl-2-morpholone prepared as described in example 2A hereinabove, and 200 ml tetrahydrofuran (THF) were placed in a three-necked flask under argon. Lithium aluminum hydride (0.2 mole) was added in small portions during a half hour period, after which the reaction mixture was refluxed for 5 hr, then cooled down. 8 ml of 10% NaOH followed by 23 ml distilled water are added with stirring, and the mixture was filtered. The solid obtained was rinsed thoroughly with THF and the filtrate concentrated. The essentially pure aminodiol is obtained upon recrystallization or distillation, which has a 90% yield, and it has a m p of 73°75° C. Upon analysis it is confirmed that it has the structure written hereinabove.
As is evident from Table I hereinbefore, the aminodiol has excellent u-v light stabilization properties.
B. Preparation of (1-hydroxy-2-methyl-2-propyl)(1-hydroxy-2-methyl-2-butyl)amine:
In a manner analogous to that described in example 3A hereinabove, 3-methyl,3-ethyl-5,5-dimethyl-2-morpholone is reduced with LiAlH 4 to provide a better than 80% yield of (1-hydroxy-2-methyl-2-propyl)(1-hydroxy-2-methyl-2-butyl)amine which has a b p of 136°-7° C./4 mm Hg.
C. Preparation of (1-hydroxy-2-methyl-2-propyl)(1-hydroxymethyl-1-cyclohexyl)amine:
In a manner analogous to that described in example 3A hereinabove, 3,3-pentamethylene-5,5-dimethyl-2-morpholone is reduced with LiAlH 4 to provide a better than 75% yield of (1-hydroxy-2-methyl-2-propyl)(1-hydroxymethyl-1-cyclohexyl)amine.
EXAMPLE 4
A. Preparation of tetramethyl-monoaza-15-crown-5.
A small amount of metallic sodium is added to 0.033 mole of di-(1-hydroxy-2-methyl-2-propyl)amine dissolved in t-butanol (250 ml) and triethylene glycol ditosylate (0.033 mole) in p-dioxane (150 ml) was added in drops during a 3 hr period at a temperature of 60° C. After the addition, the reaction mixture was filtered and the solvent was evaporated. Water was added to the residue and the solution was extracted with several aliquots of methylene chloride. The mixture was then dried and concentrated. Upon distillation pure tetramethyl-monoaza-15-crown-5 is obtained (n=3 ethylene oxide units) in better than 50% yield and has a b p of 97°-9° C./0.15 mm Hg.
B. Preparation of trimethyl-ethyl-monoaza-15-crown-5.
In a manner analogous to that described in example 6A hereinabove, (1-hydroxy-2-methyl-2-propyl)(1-hydroxy-2-methyl-2-butyl)amine is reacted with triethylene glycol ditosylate, and the reaction mixture worked up to yield about a 50% yield of a colorless oil having a b p of 122°-4° C./0.08 mm. The structure of the oil is confirmed by the usual analysis (n=3 ethylene oxide groups).
C. Preparation of dimethyl-pentamethylene-monoaza-15-crown-5.
In a manner analogous to that described in example 6A hereinabove, (1-hydroxy-2-methyl-2-propyl)(1-hydroxymethyl-1-cyclohexyl)amine is reacted with triethylene glycol ditosylate and the reaction mixture worked up to give about a 50% yield of a colorless oil having a b p of 143°-6° C./0.1 mm. The structure of the compound is confirmed by analysis (n=3 ethylene oxide units).
D. Preparation of tetramethyl-18-crown-6.
In manner analogous to that described in example 6A hereinabove, a small amount of potassium metal was used instead of sodium; di-(1-hydroxy-2-methyl-2-propyl)amine was reacted with tetraethylene glycol ditosylate, the reaction mixture worked up as before, and a colorless oil was obtained in about 40% yield which oil had a b p of 120°-3° C./0.1 mm. Upon analysis the oil is found to be tetramethyl-18-crown-6 (n=4 ethyleneoxide units).
E. Preparation of tetramethyl-12-crown-4.
In a manner analogous to that described in example 6A hereinabove, a small amount of lithium metal is used instead of sodium, and di-(1-hydroxyl-2-methyl-2-propyl)amine is reacted with diethylene glycol ditosylate. The reaction mixture is worked up as before to give about a 15% yield of tetramethyl-12-crown-4 (n=2 ethylene oxide units) which oil has a b p of 68°-9° C./0.2 mm.
All the crown ethers prepared hereinabove are found to have excellent u-v stabilization properties.
EXAMPLE 5
A. Preparation of 3,3,5,5-tetramethyl-morpholine. ##STR13##
3.0 g of di-(1-hydroxy-2-methyl-2-propyl)amine and 25 ml of methanesulfonic acid are placed in a round-bottomed flask and heated to 130° C. for more than 10 hr after which the reaction mixture is cooled down and added slowly to a 10% NaOH solution. The mixture is then extracted with 50 ml aliquots of methylene chloride several times, dried and concentrated. Upon distillation, a colorless oil is obtained in about 50% yield which boils at 63°-4° C./19 mm. It is found to be an excellent u-v stabilizer, as is evident from the data in Table I. Analysis by proton nuclear magnetic resonance (nmr) and field desorption (FD) mass spectroscopy confirms the structure of the oil as being 3,3,5,5-tetramethyl-morpholine.
B. Preparation of 3,5,5-trimethyl-3-ethyl-morpholine.
In a manner analogous to that described in example 5A hereinabove, starting with (1-hydroxy-2-methyl-2-propyl)(1-hydroxy-2-methyl-2-butyl)amine and reacting with methanesulfonic acid, then working up the reaction mixture, a colorless oil having a b p 71°-3° C./20 mm, is obtained in about 50% yield. Less than 5% by weight of the oil is found to provide excellent u-v light stability in polypropylene.
C. Preparation of 3,3-dimethyl-5,5-pentamethylene-morpholine.
In a manner analogous to that described in example 5A hereinabove, (1-hydroxy-2-methyl-2-propyl)(1-hydroxymethyl-1-cyclohexyl)amine is reacted with methanesulfonic acid and worked up to obtain about a 50% yield of colorless oil having a b p 86°-9° C./3 mm. Its structure is confirmed by GC, IR and proton nmr analysis. About 0.5-1.0% by weight in polypropylene is found to provide excellent u-v stability.
EXAMPLE 6
A. Preparation of N,N'-bis-(1-methoxy-2-methyl-2-propyl)-amine having the structure: ##STR14##
Sodium hydride (0.24 mole) is washed once with dry toluene, then suspended in 100 ml toluene. Di-(1-hydroxy-2-methyl-2-propyl)amine (0.1 mole) is added and the mixture is slowly warmed to reflux under argon. After about 1 hr the mixture is cooled down to room temperature and an alkylating agent such as methyl iodide or dimethyl sulfate (0.22 mole) in 20 ml of toluene is added dropwise over a period of about 1 hr. The reaction is stirred at ambient temperature overnight, and worked up by adding water, extracting the aqueous solution with toluene, drying the combined toluene solutions with sodium sulfate, and concentrating. The desired N,N'-bis-(1-methoxy-2-methyl-2-propyl)-amine is obtained in pure form by simple distillation, with about a 90% yield. It has a b p of 80°-2° C./10 mm Hg.
In a manner analogous to that described in example 6A hereinabove, the following aminodiethers are prepared by reacting the appropriate aminodiol and alkylating agent, respectively, and working up as described to obtain about 80% or better yields of the aminodiethers: N-(1-methoxy-2-methyl-2-propyl)-N'-(1-methoxy-2-methyl-2-butyl)amine has a b p of 91°-4° C./10 mm., and, N-(1-methoxy-2-methyl-2-propyl)-N'-[2-(methoxymethyl)cyclohexyl] amine has a b p of 111°-4° C./2 mm.
Corresponding nitroxyl compounds of the foregoing compounds may be prepared by conventional procedures such as the one described in Synthetic Communications, 5, 409 (1975). The nitroxyl is generally a orange-red colored oil showing a typical 3-line structure in elctron-spin resonance (esr) spectroscopy.
EXAMPLE 7
Process for preparation of polysubstituted 2-morpholones, whether prior art or novel compounds, and particularly tetra-substituted 2-morpholones:
The first step in the process of this invention is to prepare a 4M-HEAA having the desired substituents. It will be appreciated that these substituents are most conveniently provided by reacting a 2,2'-substituted-2-aminoethanol and a monoketone with appropriate substituents on either side of the carbonyl C, or benzaldehyde which may have ring substituents. As described in Example 1 hereinbefore, the 4M-HEAA is formed by reacting the aforesaid appropriately substituted reactants in the presence of chloroform and, preferably, in the presence of a phase transfer catalyst. In general, the 4M-HEAA is formed with no substituent on the N atom. The 4M-HEAA is then cyclized in the presence of a concentrated mineral acid as described in Example 2 hereinbefore to form a polysubstituted 2-morpholone having the general structure: ##STR15## wherein, R 1 , R 2 , R 3 and R 4 are independently selected from the group consisting of aryl, alkyl having from 1 to about 24 carbon atoms, cycloakyl having from 5 to about 7 carbon atoms, aralkyl having from 7 to about 20 carbon atoms, cyanoalkyl having from 2 to about 12 carbon atoms, ether having from 4 to about 18 carbon atoms, and hydroxyalkyl having from 1 to about 18 carbon atoms; and,
R 1 and R 2 together, or R 3 and R 4 together, or each pair, may be cyclized forming a ring having from about 5 to about 8 carbon atoms;
except that not more than one of R 1 , R 2 , R 3 or R 4 maybe hydrogen; and no more than three of R 1 , R 2 , R 3 and R 4 may be cyclic.
The N atom may be substituted, if desired, with a substituent R 5 selected from the group consisting of O, lower alkyl having from 1 to about 6 carbon atoms, and hydroxyalkyl having from 1 to about 6 carbon atoms. Such substitution is preferably effected soon after formation of the 4M-HEAA, before it is cyclized, since in most instances, making the substitution after the 2-morpholone is formed, is more difficult because of the hindrance of the substituents on the N-adjacent C atoms. As will be evident upon consideration of the problem posed by the highly hindered nature of the N atom, particularly if it is tetra-substituted rather than only tri-substituted, it is surprising that cyclization of the 4M-HEAA is effected at all by the mineral acid.
A. Preparation of 5,5-dimethyl-3-phenyl-2-morpholone:
In a manner analogous to that described in Example 1A hereinbefore, 2-amino-2-methyl-1-propanol, benzaldehyde and chloroform are reacted at ice bath temperature in the presence of a phase transfer catalyst and aqueous NaOH is added dropwise into the reaction vessel while the contents are being stirred. The sodium salt of the compound is recovered with an analogous workup, and warmed with a mineral acid to yield a compound which is a hydrochloride. When the hydrochloride is reacted with triethanolamine, the compound recovered is identified as being 5,5-dimethyl-3-phenyl-2-morpholone.
B. Preparation of [2'-(2'-cyanopropyl)]-3,5,5-trimethylmorpholin-2-one:
In a manner analogous to that described in Example 1A hereinbefore, 2-amino-1-propanol, chloroform and 4-cyano-4-methyl-2-butanone are reacted in the presence of a phase transfer catalyst with the addition of aqueous NaOH (50% solution) to form a sodium salt which is recovered and warmed with conc HCl to form the morpholone hydrochloride to which triethanolamine is added so as to yield a compound which is identified as being [2'-(2'-cycanopropyl)]-3,5,5-trimethylmorpholin-2-one.
C. Preparation of 5-methyl-3-phenyl-3-ethyl-2-morpholone:
In a manner analogous to that described in Example 1A hereinabove, 2-amino-1-propanol, chloroform and phenylethylketone are reacted to yield a sodium salt which is recovered and cyclized with conc HCl to yield a morpholone hydrochloride which upon reaction with triethanolamine yields a compound identified as being 5-methyl-3-phenyl-3-ethyl-2-morpholone.
D. Preparation of 3-[2-(2'-cyanopropyl)]-3,5-dimethyl-hydroxyethyl-morpholin-2-one:
In a manner analogous to that described in Example 1A hereinbefore, 2-amino-2-methyl-1,3-propanediol is reacted with 4-cyano-4-methyl-2-butanone and chloroform, optionally in the presence of a phase transfer catalyst, with the addition of aqueous NaOH solution, to yield a sodium salt. The salt is cyclized upon warming with conc HCl to yield a polysubstituted morpholone hydrochloride which upon reaction with triethanolamine yields a compound identified as being 3-!2-(2'-cyanopropyl)1-3,5-dimethyl-hydroxyethyl-morpholin-2-one.
E. Preparation of 5-hydroxymethyl-3,3,5-trimethyl-2-morpholone represented by the structure: ##STR16##
In a manner analogous to that described in Example 1A hereinbefore, 2-amino-2-methyl-1,3-propanediol is reacted with chloroform in excess, and acetone in large excess, optionally in the presence of a phase transfer catalyst, with the addition of aqueous NaOH solution, to yield a sodium salt. The salt is cyclized upon warming with conc HCl to yield a polysubstituted morpholone hydrochloride which upon reaction with triethanolamine yields a compound identified as having the structure given immediately hereiabove.
F. Preparation of 5-hydroxymethyl-5-ethyl-3,3-dimethyl-2-morpholone:
In a manner analogous to that described in Example 1A hereinbefore, the reaction of 2-amino-2-ethyl-1,3-propanediol with chloroform in excess, and with acetone in large excess, with the addition of aqueous NaOH solution, yields a sodium salt which is cyclized with conc HCl to yield the compound identified as having the structure given immediately hereinabove. | An essentially single stage reaction has been discovered in which a disubstituted ethanolamine, that is, a 2,2'-substituted-2-aminoethanol, may be reacted with a haloform and a carbonyl containing compound selected from the group consisting of monoketones and benzaldehyde, in the presence of an alkali metal hydroxide, and optionally in the presence of a phase transfer catalyst, to produce an alkali metal hydroxyethylaminoacetate ("HEAA") which has N-adjacent C atoms on which there are a total of at least three substituents (hence "polysubstituted"), and one or both pairs of substituents on each N-adjacent C atom may be cyclized. The HEAA may be cyclized by the action of a mineral acid to produce a 2-morpholone hydrochloride which is characterized by having a total of at least three substituents on the N-adjacent C atoms of the ring. The 2-morpholone so produced may be reduced to a polysubstituted aminodiol. The aminodiol so produced may be cyclized with an alkane sulfonic acid to yield a polysubstituted morpholine which could not otherwise have been made. The aminodiol may also be alkylated to produce diethers with polysubstituted N-adjacent C atoms. If the aminodiol is tosylated, a polysubstituted crown ether is produced with plural polyalkylene groups. The foregoing HEAA and related compounds are used as u-v light stabilizers in novel compositions in which a small but effective amount of one or more of the HEAA and related compounds is incorporated, in an amount sufficient to produce desirable stabilization against degradation by u-v light in a wide variety of organic materials. | 2 |
BACKGROUND OF THE INVENTION
The invention relates to electrical apparatus and more particularly to an adjustable interlock for safe operation of microwave ovens.
The source of microwave energy utilized in microwave ovens is the magnetron which is now well known in the art. Such magnetron generators provide for radiation of energy within an enclosure to heat any food article disposed therein. Magnetron energy generators conventionally operate from regular line sources of low frequency and low voltage which is stepped up to DC rectified voltages of 4,000 to 6,000 volts. To provide for safe operation, interlock switches have evolved in the prior art to interrupt the line power and prevent radiation of energy except when the door to the enclosure is closed. Such interlock switches prevent serious damage to the expensive equipment and are intended, with associated electrical circuitry, to substantially reduce any hazards associated with the high voltage supplies. A concern about such devices has been the possibility of radiation leakage which might result in injury to the operator. Because of this concern, the Department of Health, Education and Welfare, through the Bureau of Radiological Health (BRH), has promulgated a series of regulations specifying minimum safety precautions for microwave ovens manufactured or sold in the United States.
All such ovens are required to have a minimum of two safety interlocks. At least one safety interlock must be concealed, and the concealed interlock must not be operable by any part of the human body, any object with a straight insertable length of ten (10) centimeters, or a test magnet held in place on the oven by gravity or its own attraction.
It is further required that any visible actuating member of the concealed safety interlock must not be intended for removal by conventional tools without full or partial disassembly of the door. It must also have an apparent useful purpose and function other than interlock actuation unless access to the interlock is prevented when the door is open. Finally it is required that a means of monitoring at least one of the safety interlocks be provided to cause the oven to become inoperable if the safety interlock should fail.
Since the interlock switches are required to open and close each time the apparatus is operated, such devices must be completely reliable and adequately disable the electrical circuits at any time that a potentially hazardous condition arises. Mass production techniques compound the difficulty in attaining a truly reliable safety interlock. Assembly line manufacturing makes it necessary that the interlock be economical to produce, easy to install, convenient to adjust and consistently reliable from oven to oven. But most important, the adjustment must be precise. The accuracy of the setting cannot be compromised for ease of production.
SUMMARY OF THE INVENTION
According to this invention, in a high frequency heating apparatus of the class comprising a cabinet defining therein a heating chamber with an access opening, a door closing the access opening, a magnetron for radiating high frequency electromagnetic waves in the heating chamber, and a timer for presetting the operating time of the magnetron, there is provided an adjustable interlock switch mechanism which will positively operate each time the oven door is opened to stop operation of the magnetron.
The primary objective of the invention is to provide an interlock which can be easily and accurately adjusted in assembly line production and thereafter is only accessible to authorized service personnel.
Another object of the invention is to provide a failsafe device such that any shift in the set point of the interlock can only be in the direction of greater safety.
A further object of the invention is to provide an interlock which has relatively few total parts and a minimum of moving parts so that it is economical to produce and highly durable in use.
Another object is to make the interlock adjustment extremely precise to minimize possible radiation leakage at the instant the door is jarred or otherwise moved a predetermined distance from the closed position.
Other objects and advantages of the invention will become apparent from the following description, the accompanying drawings and the appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a microwave oven with portions broken away to illustrate an interlock mechanism positioned along the left side of the oven wall.
FIG. 2 is a side view of a microwave oven with portions broken away to illustrate an interlock mechanism positioned along the right side of the oven wall.
FIG. 3 is a side view of the right interlock mechanism.
FIG. 4 is a side view of the left interlock mechanism showing its operation.
FIG. 5 is a side view of the left interlock mechanism adjusted fully clockwise.
FIG. 6 is a side view of the left interlock mechanism adjusted fully counterclockwise.
FIG. 7 is a perspective view of the rear of a microwave oven with portions broken away to illustrate adjustment of the left interlock mechanism.
FIG. 8 is a block diagram of a microwave oven electrical circuit employing the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1 and FIG. 2 show a microwave oven 10 from the left and right sides, respectively. A hollow cavity enclosure 12 is defined by conductive walls 14. The dimensions of the enclosure are selected to excite numerous modes of microwave energy at desirably a frequency of 2,450 MHz, one of the alotted frequencies for such devices. Case 16 surrounds the oven enclosure as well as the high voltage electrical circuits, controls and microwave energy source. Control panel 18 contains means for selecting defrost time, cooking time, power levels and the like. Control panel 18 is the subject of U.S. Pat. No. 4,011,428, issued Mar. 8, 1977, and is incorporated herein by reference. Control buttons 20, 22, and 24 provide for, respectively, start, stop and light control.
The source of electromagnetic energy is the magnetron 26 and its accompanying high voltage electrical circuits, denoted by block 28. Both of these are now considered to be well known in the art and representative electrical circuits are more particularly described in U.S. Pat. No. RE 28,822, incorporated herein by reference.
Access to the oven cavity 12 is provided by opening 30. The opening is closed by the door assembly 32 which has been illustrated of the drop-down type with a bottom hinge 34. The door assembly 32 has an inner cover 36 with a window 38 of a high dielectric loss material to provide secondary energy absorbing means for any radiated energy escaping around the periphery of the opening.
Latch 40 is mounted on the door assembly and engages a mating slot 42 in a peripheral front wall 44 surrounding the access opening 30. A mechanically actuated latch locking arrangement 46 is slideably disposed within the peripheral front wall 44. An interlock switch 48 is controlled by latch 40 to break the circuit upon any opening of the door assembly while the oven is operating. Movement of the drop-down type door assembly 32 is controlled by a pair of spring-tensioned, left and right counterbalance arms 50 and 52, respectively. Tension spring 58 works in conjunction with arm 50, and tension spring 158 works in conjunction with arm 52.
In FIG. 1 and FIG. 4, the movement of the left counterbalance arm 50 is depicted. The dotted line portion in FIG. 4 illustrates the relative position of the moving parts when the door assembly 32 is partially opened. Arm 50 is pivotally mounted on the side of the door assembly 32. A bearing member 56 of low-friction, long-wearing material, such as nylon, provides a riding surface for the arm. One end of spring 58 is attached to the inner end of arm 50. The other end is attached to the conductive wall 14' of the oven to provide the appropriate tensioning as the door is opened and closed.
FIG. 4 and FIG. 7 illustrate the parts of the safety interlock operating in conjunction with the left counterbalance arm 50. Arm 50 has a hook-shaped portion 60 which, when the door is completely closed, engages and depresses lever arm 62 to close the interlock switch 64. Terminal connectors 66, 68, and 70 connect the door interlock switch to the appropriate electrical circuit for operation of the microwave oven. The electrical circuit is further described herein in conjunction with FIG. 8.
Interlock switch 64 is mounted on interlock bracket 80 by means of two screws 63 and 65. The interlock bracket 80 is pivotally mounted on counterbalance arm bracket 78 with a press-fit rivet 82. This allows the interlock bracket 80 to be rotated clockwise or counterclockwise on bracket 78 about rivet 82. Bracket 78 is attached to the conductive wall 14 by means of rivets 79.
Brackets 78 and 80 are formed out of a heavy-gauge sheet metal. One portion of counterbalance arm bracket 78 is bent perpendicular to the vertical plane to form tab 74. Likewise, one portion of interlock bracket 80 is bent perpendicular to the vertical plane to form tab 76.
Adjustment of the interlock is accomplished by turning the adjusting bolt 72. The adjusting bolt is mounted on tabs 74 and 76 which, in turn, are connected to the counterbalance arm bracket 78 and the interlock bracket 80, respectively. Bolt 72 is held in tab 76 by speed nut 84. As bolt 72 is turned, it moves the interlock bracket 80 about the pivot point, rivet 82. This movement, in turn, changes the distance between lever arm 62 and the counterbalance arm 50. The hole in tab 76 is oversized to allow bracket 80 to pivot without moving screw 72 from its horizontal position as shown in FIG. 1.
The movement of bracket 80 relative to bracket 78 and conductive walls 14 is shown more fully in FIG. 5 and FIG. 6. In FIG. 5, interlock bracket 80 is rotated fully clockwise. In FIG. 6, interlock bracket 80 is rotated fully counterclockwise.
As shown in FIG. 4, bolt 72 is finely threaded to increase the frictional resistance to reduce the likelihood of any change in its set point ever occurring. Tabs 74 and 76 are constantly being forced apart by compression spring 86. The purpose of the spring is to make the interlock failsafe. Because of the bias caused by spring 86, any unintentional change in the set point must be in the direction of greater safety. As the tabs are pushed further apart, bracket 80 rotates counterclockwise causing lever arm 62 to move away from counterbalance arm 50.
The combination of compression spring 86 and finely threaded bolt 72 makes the adjustment extremely precise. The interlock can be accurately set to interrupt the input current to the magnetron when the door is opened a predetermined distance from the closed position. The importance of such exact operation lies in the strict standards set by the Bureau of Radiological Health. If operation of the magnetron is not always cut off before the door is opened a predetermind distance, the microwave oven may not be sold to the public.
FIG. 7 shows how the interlock switch is physically adjusted after the oven is assembled and the outer case 16 is put on. Bolt 72 has a hexagonal depression in its head. An adjusting tool 88 with a matching hexagonal head is slid through an aperture in case 16 and conductive wall 14' and engaged with bolt 72. It is guided by the plastic bolt head 90. After the interlock is properly adjusted, the hole in the case is closed with a pop rivet 92. The purpose of the rivet is to prevent adjustment by unauthorized personnel. It must be drilled out later if the interlock is to be readjusted. This is easier and safer than removing the outer case.
FIG. 2 and FIG. 3 illustrate the parts of a similar safety interlock operating in conjunction with the right counterbalance arm 52. Arm 52 has a hook-shaped portion 160 which, when the door is completely closed, engages and depresses lever arm 162 to open the interlock switch 164. Terminal connectors 166, 168, and 170 connect the door interlock switch to the appropriate electrical circuit for operation of the microwave oven.
Interlock switch 164 is mounted on interlock bracket 180 by means of two screws 63 and 65. The interlock bracket 180 is pivotally mounted on counterbalance arm bracket 178 with a press-fit rivet 82. This allows the interlock bracket 180 to be rotated clockwise or counterclockwise on bracket 178 about rivet 82. Bracket 178 is attached to the conductive wall 14 by means of rivets (not shown).
Brackets 178 and 180 are formed out of a heavy-gauge sheet metal. One portion of counterbalance arm bracket 178 is bent perpendicular to the vertical plane to form tab 174. Likewise, one portion of interlock bracket 180 is bent perpendicular to the vertical plane to form tab 176.
Adjustment of the right interlock is accomplished in the same manner as the left interlock by turning and adjusting bolt 172 with tool 88 in plastic bolt head 190. The adjusting bolt is mounted on tabs 174 and 176 which, in turn, are connected to the counterbalance arm bracket 178 and the interlock bracket 180, respectively. Bolt 172 is held in tab 176 by speed nut 84. As bolt 172 is turned, it moves the interlock bracket 180 about the pivot point, rivet 82. The hole in tab 176 is oversized to allow bracket 180 to pivot without moving screw 172 from its horizontal position as shown in FIG. 2. After the interlock is properly adjusted, the hole in case 16 is closed with a pop rivet 92.
FIG. 8 is a block diagram of an electrical circuit for a microwave oven incorporating the safety interlock. A conventional three-terminal connector 200 having a grounded lead 202 is connected to the conventional domestic or industrial line voltage source. A terminal board 204 interconnects all of the components to the line voltages. Previously described light button 24 actuates light switch 206 to illuminate the interior of the oven enclosure. In a like manner, start button 20 and stop button 22 actuate start switch 208 and stop switch 210, respectively. Interlock switch 64, described above, actuates switch 212. Right interlock switch 164 activates switch 214, and latch interlock switch 48 actuates switch 216.
When the oven door is open, switches 212 and 216 are open and switch 214 is closed. When the oven door is closed, the left interlock switch 64 closes switch 212, the latch interlock switch 48 closes switch 216, and the right interlock switch 164 opens switch 214. This prepares the oven circuitry for normal operation. When start button 20 is depressed, closing switch 208, current is supplied to the control circuit 218. The control circuit 218, like the control panel 18 referenced above, is the subject of U.S. Pat. No. 4,011,428, issued Mar. 8, 1977, and is incorporated herein by reference. Control circuit 218 energizes power relay coil 220 and pulses the gate circuit of triac 222. Relay coil 220, in turn, closes relay 224. This allows current to flow from the line source, through switches 212 and 216, and to transformer 226. Transformer 226 powers the high voltage electrical circuits 28 which power the magnetron 26.
If for any reason switch 212 should fail to open upon opening the oven door, current flows through switch 214 and to the thermal limiter 228. Switch 214 is normally closed when the door is open, as noted above. At a predetermined temperature, the thermal limiter 228 disintegrates and interrupts the line current, thereby cutting power to the magnetron 26. The thermal limiter is more particularly described in U.S. Pat. No. RE 28,822, incorporated herein by reference.
There is thus disclosed, an interlock mechanism that is readily accessible during production and thereafter only by authorized service personnel. Numerous modifications will be evident to those skilled in the art. The foregoing description of a preferred embodiment is, therefore, intended to be interpreted broadly. | An adjustable safety interlock is disclosed for microwave ovens or other high voltage electrical apparatus. The interlock is actuated by the movement of a counterbalance arm when the door is opened. The amount of movement necessary to actuate the interlock is altered by changing the position of the interlock switch relative to the counterbalance arm. The interlock switch is pivotally mounted on the side of the apparatus for this purpose. Pivotal movement of the interlock towards and away from the counterbalance arm is achieved by a finely threaded bolt. The bolt is biased in the direction of greater safety by a compression spring. The interlock is readily accessible during production and thereafter only by authorized personnel. | 8 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a process and apparatus for weaving and deweaving a fabric tape so the individual warp strands may be space dyed and wound onto separate packages for subsequent use. Deweaving the tape is an essential process when space dyeing of textile yarns is carried out via the weave-de-weave process, since the tapes themselves cannot be used as a unit for further processing.
2. Description of the Prior Art
U.S. Pat. No. 3,605,225 describes in detail a weaving process which is commonly referred to as "weave-de-weave." Weft is inserted by a needle on a narrow width needle loom and knitted in a chain stitch along one side of a tape fabric including a plurality of warp threads in order that the weft can subsequently be removed after treatment of the fabric, e.g., by coloring, and the fabric unravelled to provide a yarn with intermittent coloring or splotches which is then used as pile yarn in carpets.
As the weft is removed, the individual warp yarns from the tape are separated out and wound on single one-end packages.
Typically, the yarn used for the weft filling is either nylon or polyester of a size substantially smaller than the warp yarn through which it is woven. For purposes of economy, the weft yarn must be reclaimed for repetitive use and with each re-use, the coat of the weft per pound of carpet yarn produced is decreased. However, there are serious drawbacks in re-using the weft yarn. Owing to its fine denier and to repeated subjection to both heat (during dyeing) and stress (during weaving and deweaving), the efficiency of the latter operations decrease with each re-use.
One problem associated with weft removal in the "weave-de-weave" process, therefore, is breakage of the weft thread or the presence of a knot or tangle in the weft thread as it is deweaved. This problem is compounded by the method of weft collection in which the use of a conventional ring traveler take-up is involved, which inserts variable twist in the weft end, consequently increasing the incidence of breakage and snarls in re-use of the weft. If the weft breaks or tangles, the deweaving process must stop. Broken ends must be rethreaded and repaired, and yarn tensions readjusted, all of which gives rise to considerable process inefficiency and additionally requires operator attention.
Knots and tangles, as well as breakage, of the warp threads in the process is also a problem because of the simultaneous winding of a large number of parallel yarns onto separate packages. If a knot, tangle, or breakage of a warp thread occurs, the individual warp threads cannot be properly separated, and the entire process must stop.
The loom speed in the conventional weave-de-weave process is also limited to about 1000-1200 picks per minute. Each pick, or weft insertion, can be spaced only about 1 inch from the adjacent picks, a distance limited because the movement of warp per pick is all the loom gearing allows. If the gearing limitation is removed, the warp advance per pick is still limited by the fact that the weft is wrapped around the selvage knitting needle and cannot easily be pulled through. Since the weft is fragile for economic reasons, e.g., due to its continued removal and reuse, this further limits the speed of warp production.
Further, the weft can only be withdrawn from the fabric in a reverse operation to its insertion, so that the tape must at some point in the process be reversed end for end. The tape produced is narrow (21/2 - 3 inches) and this gives rise to problems in keeping the tape free from folds. Lastly, even with due care the weft often breaks causing the deweaving process to stop, since the weft must be pulled out.
The weave-de-weave system described herein resolves some or all of these difficulties. The advantages of our method and apparatus over the prior art include the following:
(1) Wider tapes may be made on the loom since the weft insertion system employed is not the needle arm knitting needle type which can only be used over a few inches;
(2) Wider tapes mean less chance of folds in processing;
(3) While one can have wider tapes in dyeing, the tapes can be split down to any size for winding back to packages;
(4) The tapes do not need reversing and will deweave in either direction;
(5) The deweaving does not require a continuous weft. Weft breaks do not stop the deweaving process;
(6) There is no limitation on pick spacing imposed by the loom; and
(7) The system allows a continuous unwinding of weft from the supply package. Accordingly, the present invention provides a weave-de-weave process and apparatus characterized by increased speed and operating efficiency.
SUMMARY OF THE INVENTION
These objectives and advantages are achieved by inserting the weft between the warp from opposite sides of the tape using an air gun. The picks are not knitted to each other, but are interweaved with the warp and alternated to either form a selvage along opposite edges of the tape or an overlap, for a portion of adjacent lengths, along the longitudinal center of the tape.
The weft is withdrawn in a controlled manner from its supply package continuously in loops prior to each insertion in the warp by the air gun. This greatly reduces variations in weft tension and potential breakage. Because knitting needles are not employed to form the tape and insert the weft, the tape formed by the process of the present invention may be substantially wider than a conventional tape, reducing the chance of folds forming in the tape. The air jet system employed to weave the weft into the warp is the most rapid system of weft insertion found to date and there is no limitation on the pick spacing imposed by the loom.
After dyeing, the tape is separated into two or more tapes by driving it past a pulley mechanism, which causes the tape to diverge about it. This splits the tape apart, exposing the looped ends of each weft pick. The exposed looped ends of each weft pick are caught by the pulley mechanism and pulled from the warp and deposited in a suitable container wherein they can be remelted and reextruded for reuse, or merely rewound into packages.
Because of the method used for removing the weft, the removal of the weft does not depend on weft continuity, as in the prior art, and thus will work equally as well with broken weft. No reversal of the tape is required to remove the weft, which results along with weft breakage in the prior art, in substantial downtime of the deweaving apparatus.
The tape can be split down into any number of tapes for convenience of handling and rewinding the warp back to packages.
BRIEF DESCRIPTION OF THE DRAWINGS
Further objects and advantages of the invention will become apparent from the following description and claims, and from the accompanying drawings, wherein:
FIG. 1 is a diagrammatic side view of the weave-de-weave apparatus of the present invention;
FIG. 2 is a diagrammatic plan view of a portion of the apparatus of FIG. 1 at the weft insertion station;
FIG. 3 is a top plan view of another portion of the apparatus of FIG. 1 at the weft removal station;
FIG. 4 is a side view in elevation of the weft removal mechanism at the weft removal station illustrated in FIG. 3; and
FIG. 5 is an end view in elevation of the mechanism of FIG. 4 as seen from the right-hand side of FIG. 4.
FIG. 6 is a top plan view of an alternate form of fabric tape which can be deweaved in accordance with the principles of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the drawings in detail, wherein like numerals indicate like elements throughout the several views, the weave-de-weave apparatus of the present invention is illustrated diagrammatically in FIG. 1.
Warp yarns 12 are fed continuously from a creel 14 containing yarn packages down guide tubes 16, through an eyeplate 18 and about a pressure roller 20. The warp yarns 12 are forced to turn about a drum 22 against the restraining influence of a braking mechanism 24, which can be adjusted to vary the tension on the warp yarns 12 being withdrawn from creel 14.
Brake mechanism 24 includes a flexible belt 26 having one end connected about the shaft of pressure roll 20 and entrained about a drum 28 coaxially mounted on shaft 30 rotatably carrying drum 22. The other end of belt 26 is connected to a coil spring 32 fixed to a bolt 34 received through the arm of a bracket 36 mounted on the frame of the apparatus. Bolt 34 is threadedly received through a nut 38.
By rotating nut 38, the tension exerted by spring 32 on belt 26 and consequently its frictional engagement with brake drum 28 can be varied, varying the freedom of feed rotation of drum 22 about its circumference on yarns 12, and consequently the tension applied to the yarns 12 by a pair of draw rolls 40, 42 downstream from drum 22, drawing the yarns along the apparatus.
The tensioned yarns 12 pass beneath a second pressure roll 44 and between a conventional yarn detector system 46 which serves as a stop motion for the apparatus upon sensing a missing warp end. Yarns 12, downstream from detector 46, pass between a pair of bars 48, 50 which serve as lift stops for warp yarns 12 during the shedding action imparted to the yarns by conventional heddles 52, 54, which alternately lift and spread the adjacent warp yarns for insertion of the weft therebetween at a weft insertion station 56, as will be described hereinafter.
After the weft is inserted, the composite tape (warp and weft) is drawn and pulled by rolls 40 and 42 and fed to storage containers or the dyeing machinery, After dyeing, the dyed tape is passed through a guide 60, split into one or more tapes at a weft removal station 62, as will be described hereinafter, and the weft removed by a pulley mechanism 62, which strips the weft 64 and deposits it for rewinding or remelting in a container 66.
In the conventional weave-de-weave process, the weft filling 64 is inserted by a needle and knitted in a chain stitch along one side of the tape fabric between a plurality of warp threads 12 to form a unitary selvage. After treatment of the fabric tape by dyeing, the weft 12 is unwoven and removed by pulling an end to unravel the picks. The chain stitch selvage enables ready removal of the weft. The warp threads are wound into individual packages for reworking, and the weft is collected in a suitable receptacle for reuse or disposal. The weft insertion system of the present invention at station 56 utilizes an entirely different process for the weft insertion, eliminating the knitting of the weft through the warp.
With specific reference to FIG. 2, a weft propulsion air gun 68 is provided on opposite sides of the tape at station 56. The gun 68 includes a bore 70 receiving a weft strand 64 therethrough. A fluid jet 72 controlled by a poppet valve 74 joins bore 70 at an acute angle. Poppet valve 74 is operated by a shutter arm 76 which rides on the circumference of an eccentrically mounted cam 78. When the high side of cam 78 contacts arm 76, valve 74 will open admitting air to bore 70 to push the weft 64 across the tape between the warp 12. Cam 78 may have more than one high lobe to operate valve 74 more than once during each revolution of cam 78 depending on the speed of the tape and number of picks per inch desired to be woven.
As shown in FIG. 2, weft 64 is inserted alternately from each side of the tape in a continuous loop 80, interweaving with the warp 12 due to the shedding action of the heddles 52, 54. The weft is fed from a feed wheel 82 which pulls the weft from a weft supply package and by an aspirator 84 which pulls the weft from wheel 82 to each air gun 68. The aspirator 84 prevents weft wraps on wheel 82. The aspirator 84 deposits the weft yarn 64 in a loose loop awaiting the next operation of the weft insertion air gun 68.
In contrast to the prior art system, the weft withdrawal from the package is continuous rather than intermittent. This greatly reduces variations in weft tension and potential breakage. The effective circumference of yarn feed wheel 82 can be increased or decreased to ensure that the exact amount of weft yarn is fed for each cycle of the apparatus. The air jet weaving of the weft provides a more rapid method of weaving the picks than was available heretofore, and provides flexibility in placing of the picks along the tape.
In this invention, only one tape of double normal width and using the same number of warp ends as both tapes, is woven. Further, the conventional tape loom has two tapes woven side by side, sharing the stop motion and shedding system but having separate right and left hand weft insertion systems. This eliminates the folding problem associated with tapes formed on a narrow width needle loom.
The relative timing of the weft insertion air guns 68 and the heddle shedding action can be varied to produce different tape constructions. Referring specifically to FIG. 3, it will be seen that the weft is fed from both sides alternately and the weft loop protrudes from the edge of the tape for a short distance. In practice this could be in a range of 1/4 to 6 inches, depending on the required speed of production and stability of the tape. Each side picks alternately so that the speed of operation of the weft feed mechanism is half the number of picks per minute. Each weft loop is always in the same position relative to the warp ends. The left hand weft pick always is over the first warp end (or always under)--never under and over alternately as in normal weaving. This enables the tape to be split as shown in FIG. 3 wherein the weft 64 can be readily pulled out from between the warp 12, without tangling or knotting.
Alternatively, a pick can be inserted at each shed opening by each air gun 68 extending slightly beyond the center line of the tape as shown in FIG. 6. The picks overlap in the center to the extent necessary to give cohesion between the two tapes in processing. This provides for a faster picking rate at the loom which may or may not be advantageous but separation of weft is much easier.
In either construction, the deweaving of the tape is easier than in the prior art, and it has the tremendous advantage that the tape will deweave from either end thus avoiding having to reverse the tape container end for end as in the prior art. This allows use of much larger tape containers, avoids tangles and makes filling the container less exacting.
After dyeing in bath 58, the tape is split as shown in FIGS. 3 to 5. The section 86 is no longer a woven structure. Examining each warp end will show that the warp 12 always stays on the same side of the residual weft 64. If the warp ends are parted in a direction at right angles to their direction of travel, the weft thread is unattached and will fall out.
Accordingly, the weft removal mechanism 62 is positioned at the exit of the warp dye line where the double tape exists. The tape is split at its center line by passing it through guide 60 and causing the warp to travel about either side of the frame 90 of mechanism 62, exposing the looped ends 92 of the weft 64, which dangle from the inner sides of the split tape. Frame 90 rotatably mounts three pulleys 94, 96 and 98 drivingly connected by a belt 100. Pulley 98 is rotatably driven through its shaft 102 such that belt 100 will drive pulley 94 and 96 at a peripheral speed several times the speed of the tape.
The dangling, exposed looped ends 92 of the weft 64 extend across the face of middle pulley 96, which will contact the looped ends and carry them successively upwardly between the V-grooves and belt 100 in pulley 96 and then downwardly around pulley 98, stripping the weft 64 from the warp 12 and depositing the stripped weft in container 66. The warp 12 is then wound on separate package 104. Since the pulleys run faster than the tape, the weft is pulled out in the same direction as the tape is running.
The weft removal mechanism 62 does not depend on weft continuity and will work equally well with broken weft, as successive looped ends 92 are gripped by the pulleys. There is also no restriction to only two tapes. Separation can be effected into any number of tapes. The restriction on warp ends is only that due to the reed space available and the density required for printing. | A weave-de-weave process in which a plurality of weft loops are fluidly injected from opposite sides and normal to a plurality of warp yarns to form a composite tape. The tape is deweaved after the warp is space dyed by splitting the interior of the tape to expose the looped ends of the weft. | 3 |
CHEMICAL SOFTENING COMPOSITION FOR PAPER PRODUCTS
[0001] This application is a divisional application of U.S. patent application Ser. No. 10/374,457 which was filed on Feb. 26, 2003 and which is currently still pending.
TECHNICAL FIELD
[0002] The present invention relates to compositions of matter and processes useful for treating paper and other materials and products which contain cellulosic fibers. More particularly, it relates to increasing the degree to which paper products and fabrics feel soft to the touch.
BACKGROUND INFORMATION
[0003] Making paper or textile products soft without impairing performance characteristics such as strength or absorbency has long been the goal of various workers. Softness is the tactile sensation perceived by a person who holds a particular paper or textile product and rubs it across the skin. Such tactilely-perceivable softness can be characterized by, but is not limited to, friction, flexibility, and smoothness, as well as subjective descriptors, such as a feelings of lubriciousness, or softness textures reminiscent of velvet, silk, or flannel. However, improvement of softness in almost all cases comes at the expense of strength or absorbancy of the fibrous material.
[0004] One method for improving softeness in paper products is to select or modify cellulose fiber morphologies to those which provide advantageous microstructures. However, while incorporation of upgraded cellulose fiber sources into paper products can improve softness, it is often the case that upgraded fiber sources offer limited ability to confer the properties of durability and absorbency to paper products produced therefrom, and the resulting paper products are typically possessed of the best achieveable balance between softness and strength for the treatment method or system utilised.
[0005] Another area that has received a considerable amount of attention in improving paper softness is the addition of chemical softening agents to the fiber furnish during the papermaking process. For example, chemical softening agents can be applied to the paper web during its formation either by adding the softening agent to the vats of pulp which will ultimately be formed into a paper web, to the pulp slurry as it approaches a paper making machine, or to the wet paper web as it resides on a Fourdrinier cloth or dryer cloth on a papermaking machine. In addition, the chemical softening agent can be applied to a finished paper web after it has dried.
[0006] To ensure an optimum level of softening efficiency in general, a high degree of attraction of the chemical softening composition to the fibers used in the manufacture of papers is necessary. It has been known that, because of their charge, cationic softeners have a strong affinity for the papermaking fibers and are a good softener. In comparison, anionic debonders, because they have the same charge as the fiber, are not sufficiently retained on the fiber furnish to function effectively as softeners. In addition, anionic debonders contribute to wet-end deposition and significant foaming that is in general overall detrimental to the papermaking process. Nonionic surfactants have no ionic attraction for the fibers whatsoever, and as a result, when nonionics are employed it is necessary for them to be applied to the wet paper web.
[0007] During the papermaking process, cationic debonders, when employed, are typically added to water to make an emulsion, and then added to the fiber furnish. Unfortunately, addition of cationic debonders to the fiber furnish often results in a significant reduction of strength in the paper web (strength being the ability of the paper product, and its constituent paper webs, to maintain physical integrity and to resist tearing, bursting, and shredding under use conditions). This reduction in strength is believed to result from a disruption of hydrogen bonds between the papermaking fibers that are formed as a result of the papermaking process. In order to offset the effects of the strength reduction that occurs because of the cationic debonder addition, dry strength additives must be added; however, these additives often negate the softness benefits imparted by the cationic debonder addition.
[0008] Various compositions are known in the art as being useful for conferring softness to paper products For example, published U.S. Patent Application No. 20020112831 discloses a paper softening composition containing a quaternary ammonium compound, water, and a nonionic surfactant. Other compositions and methods for paper softening are disclosed in U.S. Pat. Nos. 6,458,343; 6,369,007; 6,315,866; 6,245,197; 6,200,938; 6,179,961; 6,004,914; 5,753,079; 5,538,595; 5,385,642; 5,322,630; 5,240,562; 4,959,125; 4,940,513; 4,720,383; 4,441,962; 4,351,699; and 3,554,862, the entire contents of which aforesaid patent documents are herein incorporated by reference thereto in their entirety.
[0009] One of the most important physical properties related to softness is generally considered by those skilled in the art to be the strength of the paper web. Accordingly, there is a continuing need for soft paper and textile products having good strength properties. There is also a need for improved softening compositions that can be applied to such paper and textile products to provide the requisite softness without unacceptably degrading the strength of the product.
SUMMARY OF THE INVENTION
[0010] The present invention provides chemical softening compositions useful for softening fibers of cellulosic materials, including paper, without seriously detracting from the strength of final products formed through their use. A composition according to the invention includes: an amide-substituted quaternary imidazolinium salt; a nonionic surfactant; and a polyhydroxy compound. In one form of the invention, the nonionic surfactant includes ester adducts of polyethylene glycol, and the polyhydroxy compound is selected from the group consisting of: glycerine, a polyalkylene glycol, or mixtures of the foregoing.
[0011] The present invention also provides a process for making a soft durable paper web by applying a chemical softening composition described in accordance with the invention to fibers employed in the papermaking process. Such a process according to the invention comprises the steps of forming an aqueous dispersion of papermaking fibers, dewatering the dispersed fibers by depositing them onto a flat surface, and drying the dispersed fibers sufficiently to form a paper product. The chemical softening composition can be applied directly to the dispersed fibers either prior to, or subsequent to the dewatering step.
[0012] A chemical softening composition according to the present invention may also be applied to fabric (that is, articles of clothing, or textiles) to impart softness properties to the fabric, as well as increasing their ease of handling and lubricity, and reducing their tendency to accumulate and store static electricity.
[0013] Any cellulosic material, including without limitation paper fibers and fabrics, may be treated in accordance with the present invention. Any material bearing cellulose may be treated by contact with an aqueous solution according to the invention.
DETAILED DESCRIPTION OF THE INVENTION
[0014] The chemical softening composition according to the present invention comprises a amide-substituted quaternary imidazolinium salt, a nonionic surfactant, and a polyhydroxy compound. A chemical softening composition according to a preferred form of the invention comprises any amount from about 1.00% to about 20.00% by weight based on the total weight of the finished composition of the amide-substituted quaternary imidazolinium salt. It is preferred that the nonionic surfactant component be present in any amount between 20.00% and 90.00% by weight based upon the total weight of the composition. According to a preferred form of the invention, the polyhydroxy compound component is present in any amount between 1.00% and 20.00% by weight based upon the total weight of the composition.
[0015] In order to provide a composition according to the invention, the various components are merely mixed together using conventional mechanical agitation and mixing means known to those with skill in the art as being useful for combining liquids to form mixtures, including blending in a tank or passing the liquids through a static mixer, or other functionally-equivalent means of agitation.
[0016] Preferably, the amide-substituted quaternary imidazolinium salt is formed from quatemizing (alkylating) a material having the following general structure:
with dimethyl sulfate, diethyl sulfate, or an monoalkyl halide such as, preferably, the bromides or chlorides of alkanes such as methane and ethane, as such alkylations are well known to those skilled in the art. The material above may be produced by reaction between diethylenetriamine and 2 moles of a carboxylic acid (preferably a fatty acid) and the subsequent removal of water, which techniques are known by those skilled in the art. In addition, such materials are available from Huntsman International LLC of The Woodlands, Tex. In the embodiment in which dimethyl sulfate is employed as the alkylating agent, the amide-substituted quaternary imidazolinium salt is the quaternized (quaternary) amide-substituted imidazolinium methosulfate salt (II) having the general structure shown below:
in which R is independently in each occurrence a hydrocarbyl group having any number of carbon atoms between 8 and 22. It is believed to be readily appreciated by those skilled in the art that in cases where sulfates other than dimethyl sulfate are employed in quatemizing, the anion in the formula above will correspond to the anion of the other sulfate used, as such is known to those skilled in the art of the use of sulfates in alkylations.
[0017] The term “hydrocarbyl” as used in this specification and the claims appended hereto refers to a hydrocarbon group having a carbon atom directly attached to the remainder of the molecule and having predominantly hydrocarbon character. Examples of hydrocarbyl substituents or groups within this definition include: (1) hydrocarbon substituents, that is, aliphatic (e.g., alkyl or alkenyl), alicyclic (e.g., cycloalkyl, cycloalkenyl) substituents, and aromatic-, aliphatic-, and alicyclic-substituted aromatic substituents, as well as cyclic substituents wherein the ring is completed through another portion of the molecule (e.g., two substituents together form an alicyclic radical); (2) substituted hydrocarbon substituents, that is, substituents containing non-hydrocarbon groups which, in the context of this invention, do not alter the predominantly hydrocarbon substituent (e.g., halo (especially chloro and fluoro), hydroxy, alkoxy, mercapto, alkylmercapto, nitro, nitroso, and sulfoxy); (3) hetero substituents, that is, substituents which, while having a predominantly hydrocarbon character, in the context of this invention, contain other than carbon in a ring or chain otherwise composed of carbon atoms. Heteroatoms include sulfur, oxygen, nitrogen, and encompass substituents such as pyridyl, furyl, thienyl and imidazolyl. In general, no more than two, preferably no more than one, non-hydrocarbon substituent will be present for every ten carbon atoms in the hydrocarbyl group; typically, there will be no non-hydrocarbon substituents in the hydrocarbyl group.
[0018] It is readily appreciable by those skilled in the art that commercial fatty acids may in some cases be comprised of mixtures of fatty acids having different hydrocarbon tails representing a distribution of several different carbon numbers. Accordingly, a finished solution according to the invention when prepared using fatty acids as a raw material will thus often include a mixture of different cations derived from the alkylation of the material defined by the structure of the imidazoline (I) above which may have two hydrocarbyl R groups that individually may either comprise the same or different chain lengths as each other (i.e., both R 1 groups of a given cation, structure (III) below, may be the same or different). According to one form of the invention, the mixture comprises at least two quatrenary cations which differ in structure with respect to the identity of the R 1 groups present, within the meaning of the term hydrocarbyl.
[0019] A amide-substituted quaternary imidazolinium salt useful in accordance with the present invention can be prepared by any of the means well known to those skilled in the chemical arts. For example, it can be prepared by forming an amide by reacting 1 mole of diethylenetriamine with 2 moles of a fatty acid selected, without limitation from the group consisting of: oleic acid; palimitic acid; stearic acid; linoleic acid; linolenic acid; decenoic acid; decanoic acid; dodecanoic acid; hexadecanoic acid; octanoic acid; and tetradecanoic acid. Any known carboxylic acid having between 8 and 22 carbon atoms is suitable for forming such amide, whether saturated, mono-unsaturated, or poly-unsaturated. The amide is subsequently quaternized using dimethyl sulfate, which general methylation method is familiar to those skilled in the art.
[0020] A chemical softening composition according to one form of the present invention includes from 1.00 percent to 20.00 percent by weight of amide-substituted imidazolinium methosulfate salt. More preferably, the chemical softening composition includes from 3.00 percent to 15.00 percent by weight of the amide-substituted imidazolinium methosulfate salt. Most preferably, the chemical softening composition includes from 5.00 percent to 10.00 percent by weight of the amide-substituted imidazolinium methosulfate salt. It has been found that addition of a chemical softening composition having greater than 20.00 percent by weight of the amide-substituted imidazolinium methosulfate salt during the papermaking process negatively impacts the strength of the paper web during processing as well as the resulting paper product.
[0021] The nonionic surfactant of the present invention includes ester adducts of ethylene oxide, polyethylene glycol, polypropylene glycol and fatty materials such as fatty acids, alcohols, and esters. Generally, the fatty moiety of the nonionic surfactant can include from about twelve (12) to about eighteen (18) carbon atoms. The ethylene oxide moiety of the nonionic surfactants can include from two (2) to twelve (12) moles of ethylene oxide.
[0022] Examples of nonionic surfactants that can be used are polyethylene glycol dioleate, polyethylene glycol dilaurate, polypropylene glycol dioleate, polypropylene glycol dilaurate, polyethylene glycol monooleate, polyethylene glycol monolaurate, polypropylene glycol monooleate and polypropylene glycol monolaurate. The present invention contemplates the use of any known nonionic surfactant in its compositions and processes.
[0023] The nonionic surfactant can also include blends of ester adducts of polyethylene glycol and polypropylene glycol. Particularly preferred are blends of polyethylene glycol dioleate and polyethylene glycol dilaurate. For example, the nonionic surfactant of the present invention can include a blend of polyethylene glycol 400 dioleate and polyethylene glycol 200 dilaurate having from about twenty 20.00 to about eighty 80.00 percent by weight of polyethylene glycol 400 dioleate and from about 20.00 to about 80.00 percent of polyethylene glycol 200 dilaurate. Preferably, the nonionic surfactant blend contains from about thirty 30.00 percent to about seventy 70.00 percent of polyethylene glycol 400 dioleate and from about thirty 30.00 percent to seventy 70.00 percent by weight of polyethylene glycol 200 dilaurate, and most preferably from about thirty five 35.00 percent to about sixty 60.00 percent by weight of polyethylene glycol 400 dioleate and from about thirty five 35.00 percent to about sixty 60.00 percent by weight of polyethylene glycol 200 dilaurate.
[0024] The polyhydroxy compound of the present invention can be selected from the group consisting of: polyols, glycerine (glycerol), polyethylene glycols and polypropylene glycols. Preferably, the polyhydroxy compound has an average molecular weight from about 200 to about 4000, more preferably from about 200 to about 1000 and most preferably from about 200 to about 600. An example of a polyhydroxy compound useful as a component of the present invention includes POGOL® 400 sold by Huntsman International LLC (The Woodlands, Tex.).
[0025] The polyhydroxy compound is added to the chemical softening composition of the present invention so that the chemical softening composition contains from about one 1.00 percent to about twenty 20.00 percent by weight of the polyhydroxy compound. More preferably, the chemical softening composition contains from about one 1.00 percent to about ten 10.00 percent by weight of the polyhydroxy compound, and most preferably from about one 1.00 percent to about five 5.00 percent by weight of the polyhydroxy compound.
[0026] The papermaking fibers utilized in the present invention comprises fibers derived from wood pulp. Other cellulosic fibrous pulp fibers, such as cotton linters, bagasse, etc., can be utilized and are intended to be within the scope of this invention. Synthetic fibers, such as rayon, polyethylene and polypropylene fibers, may also be utilized in combination with natural cellulosic fibers. One exemplary polyethylene fiber that may be utilized is PULPEX®, available from HERCULES INCORPORATED. (Wilmington, Del.).
[0027] Wood pulps which may be treated using a composition according to the present invention include the chemical pulps such as Kraft, sulfite, and sulfate pulps, as well as mechanical pulps including groundwood, thermomechanical pulp, and chemically-modified thermomechanical pulp. Chemical pulps, however, are preferred raw materials since they impart a superior tactile sense of softness to sheets made therefrom. Those pulps derived from both deciduous trees (hereinafter, also referred to as “hardwood”) and coniferous trees (hereinafter, also referred to as “softwood”) may be utilized. Also treatable in accordance with the present invention are fibers derived from recycled paper, which may contain any or all of the above categories as well as other non-fibrous materials such as fillers and adhesives used to facilitate the original papermaking.
[0028] A chemical softening composition according to the present invention can be used with any known technique for preparing paper products. Generally, the process for the manufacture of paper with which the chemical softening composition of the present invention is useful includes the steps of establishing a uniform aqueous dispersion of papermaking fibers, forming that dispersion into a flat sheet, and dewatering and drying the sheet to form paper that can be rolled, cut, and formed as desired into any one of several finished products including napkins, toweling, and facial and toilet tissue. During processing, the chemical softening composition may be applied directly to an aqueous dispersion of papermaking fibers either prior to or after dewatering to provide a soft, durable paper web.
[0029] For example, a chemical softening composition according to the invention is used in a typical papermaking process, where an aqueous dispersion of papermaking fibers is first provided from a pressurized headbox. The head box has an opening for delivering a thin deposit of the dispersed fibers onto a Fourdrinier wire to form a wet paper web. As used herein, the terms “paper web” or “wet paper web” are intended to designate any of the nonwoven materials commonly used as paper products from which a portion thereof includes papermaking fibers.
[0030] The wet paper web is dewatered to a fiber consistency of between about 7% and about 25% (total web weight basis) by vacuum dewatering and further dried by pressing operations where the paper web is subjected to pressure developed by opposing mechanical members such as cylindrical rolls. The dewatered paper web can then be further pressed and dried by a steam drum apparatus known in the art as a Yankee dryer. Pressure is developed at the Yankee dryer by mechanical means such as an opposing cylindrical drum pressing against the paper web. Multiple Yankee dryer drums can also be employed for additional pressing if necessary or desirable. Subsequent processing such as creping, calendering and/or reeling can also be used to further increase stretch, bulk and softness, and to control caliper.
[0031] As described above, the aqueous dispersion of papermaking fibers are obtained by any of the numerous known processes, such as pulp of virgin pulpwood, from recycled paper and/or cardboard stock, or mixtures thereof. The pulp is subjected to treatment by any of several conventional processes to help establish a dispersion of fibers sufficiently finely dispersed to constitute an acceptable dispersion that can be processed into paper. The pulp can also be treated, for example, mechanically, chemically, or both, and is often subjected to heat to convert it to a processable dispersion. Several chemical processes such as the Kraft process are well known in this field.
[0032] The papermaking fibers, as that term is used herein, include any of a chemical constituency and physical form that can be formed into an aqueous dispersion that can in turn be produced into paper. Generally the papermaking fibers are predominantly cellulosic but may also contain lignins, hemi-cellulosics, and other fibrous components derived from synthetic polymers, cloth, and the like.
[0033] The aqueous dispersion of papermaking fibers is formed into a flat sheet, usually by means of a machine specially adapted for this function. Preferably, a Fourdrinier or equivalent machine presenting a wide, flat, porous screen (which can move at a predetermined rate) has at one end a means such as a headbox which contains the aqueous dispersion of papermaking fibers and which feeds the aqueous dispersion at a controlled rate onto one end of the screen.
[0034] The flat sheet formed in this or any equivalent manner still contains a substantial portion of water. As the flat sheet is carried along on the screen, water is removed through the screen by its own weight and often with the aid of pressure, heat, or both. The flat sheet can then be treated with other equipment such as heated calender rollers or the like, which further reduces the moisture content until the sheet is sufficiently dried into paper. The paper is then stored, cut and/or otherwise converted in known manner into useful products.
[0035] During processing, a chemical softening composition according to the invention may be added at any one of a variety of locations. For example, the chemical softening composition can be added to the locations where the papermaking fibers are in aqueous dispersion such as the head box, the machine chest or stuff box. The chemical softening composition can also be sprayed onto a wet paper web or applied to a dried paper web. The chemical softening composition can also be effectively applied to the papermaking fibers during the drying process or subsequent to the drying process, such as spraying the chemical softening composition onto the calender rolls.
[0036] Preferably, the chemical softening composition is applied to the aqueous dispersion of papermaking fibers prior to dewatering. It has been found that the chemical softening composition of this invention is highly retained on the papermaking fibers when it is added to the aqueous dispersion of papermaking fibers before formation of the paper web or to a wet paper web, therefore making the chemical softening composition highly effective.
[0037] While not wishing to be bound by theory, it is believed that, due to the formation of mixed component micelles, the nonionic surfactant and polyhydroxy components of the chemical softening composition described in this invention have the ability to retain on the papermaking fibers when the chemical softening composition is added to an aqueous dispersion of fibers before they are formed into a wet web. The mixed micelles contain mixtures of the amide-substituted imidazolinium methosulfate salt, nonionic surfactant and polyhydroxy compound. The cationic nature of the imidazoline makes the chemical softening composition highly attractive to the fibers. The aggregation or the interaction of the nonionic surfactants and polyhydroxy components with imidazoline results in retention of the nonionic components on the fibers. This phenomenon has been found to lead to a synergistic mixture, resulting in an improved softness when compared to use of the individual components alone. Furthermore, it is believed that the chemical softening composition reduces the surface tension on and within the interstices of the papermaking fibers, thereby debonding them yet also permitting them to mesh together more closely, thus providing a stronger sheet of paper.
[0038] In addition, a reduction in, or elimination of, foaming can be expected when using a chemical softening composition according to the invention when it is added to the papermaking fibers at the wet-end of the process. That is, the nonionic surfactant, polyhydroxy compound and the amide substituted amide-substituted quaternary imidazolinium (methylsulfate or ethylsulfate) salt will increase surface tension to levels significantly higher than those obtained when using either an anionic surfactant alone, or an unbalanced blend of anionic and cationic softening agents.
[0039] The present invention provides a chemical softening composition having the ability to impart to fabric (that is, articles of clothing, textiles, and so forth), properties including softness to the touch, ease of handling, increased lubricity, and a reduced tendency to carry or generate static electricity. One form in which the chemical softening composition of the present invention is provided is as a liquid, for instance, as an emulsion or as a solution/suspension. During use, an appropriate controlled amount of the chemical softening composition is employed, for example, by pouring the liquid chemical softening composition directly into a washing machine. Typically, the liquid chemical softening composition is dispensed during the rinse cycle of the washing machine by either pouring in by hand or metering in by an appropriate automatic metering device with which the washing machine is equipped. What now follows is illustrative of the invention, and not delimitive in any way.
EXAMPLE 1
Tissue Softness and Stability Evaluation
[0040] Test solutions were prepared to determine the ability of a chemical softening composition according to the present invention to soften paper. The test solutions used during this evaluation were prepared in deionized (DI) water so as to make a one (1) percent by weight solution of the materials described for each Sample described below:
[0041] Sample 1: Eighty 80.00% by weight of a amide-substituted quaternary imidazolinium methylsulfate salt having the general structure:
wherein R is an oleic acid residue, is combined with twenty 20.00% by weight POGOL® 400. This product is sold by Huntsman International LLC (The Woodlands, Tex.) under the trade name “HARTOSOFT”® DBS-5080M”.
[0042] Sample 2: pure Polyethylene glycol (“PEG”) 200 dilaurate.
[0043] Sample 3: pure PEG 400 dioleate.
[0044] Sample 4: 10% by weight of Sample 1+90% by weight of PEG 200 dilaurate.
[0045] Sample 5: 10% by weight of Sample 1+40% by weight of PEG 400 dioleate+50% by weight of PEG 200 dilaurate.
[0046] Sample 6: 10% by weight of Sample 1+20% by weight of PEG 400 dioleate+70% by weight of PEG 200 dilaurate.
[0047] Sample 7: 10% by weight of Sample 1+20% by weight of PEG 600 DO+70% by weight of PEG 200 dilaurate.
[0048] Sample 8: 10% by weight of Sample 1+20% by weight of PEG 400 MO+70% by weight of PEG 200 dilaurate.
[0049] Sample 9: PEG 400 MO.
[0050] The test solutions were then assessed for their ability to soften paper using 7″×3″ sections of untreated standard tissue paper. Each tissue was immersed into the specified test solution for 60 seconds and then withdrawn. The treated tissue samples were then dried in an oven at 25° C. The treated tissues were evaluated objectively and ranked for softness to the touch using the following scale:
0=Poor/harsh texture 1=Fair 2=Good 3=Very Good 4=Excellent/very soft texture
[0056] The results of this testing are reported below in Table 1:
TABLE 1 Sample Softness Deionized Water 0 Sample 1 3 Sample 2 3 Sample 3 3 Sample 4 3.5 Sample 5 4 Sample 6 3.5 Sample 7 — Sample 8 — Sample 9 1.5
[0057] The inventive chemical softening compositions, Samples 5, 6, and in particular Sample 5, show superior softness as compared to the prior art.
[0058] The stability of the test solutions was also evaluated. The following scale was used to grade the stability of the test solutions:
0=very unstable (i.e. solution separates into visible layers within 1 minute) 1=fair 2=good 3=very good 4=excellent
[0064] The results of this testing is reported below in Table 2:
TABLE 2 Sample Stability of 1% Test Solution Sample 1 1 Sample 2 0 Sample 3 0 Sample 4 1 Sample 5 3 Sample 6 2 Sample 7 2/3 Sample 8 2/3 Sample 9 3
[0065] It is shown that inventive Sample 5 is much more stable than the prior art treatments, as well as the individual components, thus indicating unexpected beneficial interactions between the amide-substituted quaternary imidazolinium methylsulfate salt, the nonionic surfactant and the polyhydroxy compound. Furthermore, Sample 5 was found to have a very low pour point (ASTM D-97), below 10° C., as compared to about 31° C. for Sample 2. Therefore, addition of a nonionic surfactant blend of PEG 400 dioleate and PEG 200 dilaurate to the amide-substituted quaternary imidazolinium methosulfate salt and polyhydroxy compound is demonstrated to lower the pour point significantly. Thus, in addition to providing superior softness and strength to paper web and its resulting paper product, the chemical softening composition of the present invention is shown to exhibit low pour points, is low foaming, and excellent dispersibility in water.
[0066] While the aforesaid embodiments are concerned with a single most preferred imidazolinium salt, the present invention embraces aqueous compositions which comprise a cation having the structure:
wherein R 1 in each occurrence is independently selected from the group consisting of: hydrogen or any hydrocarbyl group comprising 8 to 22 carbon atoms and wherein R 2 is selected from the group consisting of: hydrogen, methyl, or ethyl. The anionic counterion present with such a cation is really of little consequence to the overal performance of a solution according to the invention as heretofore described. Thus any suitable counteraion sufficient to render the solution as a whole electronically neutral is useful in accordance with the present invention. Dimethyl sulfate is a particularly preferred material for the alkylation and the presence of the methylsulfation anion is merely for convenience. Alkylations carried out using, say, methyl chloride or ethyl chloride, will result in a halide anion being present in the product, which is of no detriment from a performance standpoint. Suitable alkylating agents known in the art which are capable of alkylating the nitrogen atome bearing a methyl group in the above structure and having any number of carbon atoms between 1 and 12 are suitable for use in preparing an imidazolinium cation suitable for use in accordance with the present invention. However, as the alkyl chain becomes longer than about 2 carbon atoms, reaction product yields are adversely affected by the bulkiness of such substituents (steric effects) and for this reason alone the methyl and ethyl substituted materials are preferred components of a composition according to the invention.
[0067] Consideration must be given to the fact that although this invention has been described and disclosed in relation to certain preferred embodiments, obvious equivalent modifications and alterations hereof will become apparent to one of ordinary skill in this art upon reading and understanding this specification and the claims appended hereto. Accordingly, the presently disclosed invention is intended to embrace all such modifications and alterations, and is limited only by the scope of the claims which follow. | A chemical softening composition includes a amide-substituted quaternary imidazolinium salt, a nonionic surfactant, and a polyhydroxy compound for use in treating cellulosic materials including papers, textiles and fabrics. The chemical softening composition can be applied to papermaking fibers during a papermaking process to provide a softened paper web and product possessed of sufficient tensile strength for its regular employment. A chemical softening composition according to the invention can also be applied to fabric to soften the fabric, provide easier handling of the fabric, and also reduce the tendency of the fabric to generate and store static electricity. | 3 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to the composition, preparation, and use in elastomer compositions of latent mercaptosilane coupling agents containing siloxane bonds. These coupling agents represent an improvement over the prior art in that their use is accompanied by reduced volatile organic compound (VOC) emissions.
2. Description of Related Art
Latent mercaptosilane coupling agents known in the art contain hydrolyzable groups that are converted to volatile byproducts when the coupling agents react with the fillers used in the rubber compositions.
The majority of art in the use of sulfur-containing coupling agents in rubber involves silanes containing one or more of the following chemical bond types: S—H (mercapto), S—S (disulfide or polysulfide), or C═S (thiocarbonyl). Mercaptosilanes have offered superior coupling at substantially reduced loadings; however, their high chemical reactivity with organic polymers leads to unacceptably high viscosities during processing and premature curing (scorch). Their undesirability is aggravated by their odor. As a result, other, less reactive coupling agents have been found. Hence, a compromise must be found between coupling and the associated final properties, processability, and required loading levels, which invariably leads to the need to use substantially higher coupling agent loadings than would be required with mercaptosilanes, and often also to the need to deal with less than optimal processing conditions, both of which lead to higher costs.
Acylthioalkyl silanes, such as CH 3 C(═O)S(CH 2 ) 1-3 Si(OR) 3 and HOC(═O)CH 2 CH 2 C(═O)S(CH 2 ) 3 Si(OC 2 H 5 ) 3 are disclosed in Voronkov, M. G. et al. in Inst. Org. Khim ., Irkutsk, Russia and U.S. Pat. No. 3,922,436, respectively.
U.S. Pat. No. 3,957,718 discloses compositions containing silica, phenoplasts or aminoplasts, and silanes, such as xanthates, thioxanthates, and dithiocarbamates; however, it does not disclose or suggest the use of these silanes as latent mercaptosilane coupling agents, nor does it suggest or disclose the advantage of using them as a source of latent mercaptosilane.
U.S. Pat. Nos. 4,184,998 and 4,519,430 disclose the blocking of a mercaptosilane with an isocyanate to form a solid that is added to a tire composition, which mercaptan reacts into the tire during heating, which could happen at any time during processing since this is a thermal mechanism. The purpose of this silane is to avoid the sulfur smell of the mercaptosilane, not to improve the processing of the tire. Moreover, the isocyanate used has toxicity issues when used to make the silane and when released during rubber processing.
Australian Patent AU-A-10082/97 discloses the use in rubber of silanes of the structure represented by
R 1 n X 3-n Si—(Alk) m (Ar) p —S(C═O)—R
where R 1 is phenyl or alkyl; X is halogen, alkoxy, cycloalkoxy, acyloxy, or OH; Alk is alkyl; Ar is aryl; R is alkyl, alkenyl, or aryl; n is 0 to 2; and m and p are each 0 or 1, but not both zero. This patent, however, stipulates that compositions of the structures of the above formula must be used in conjunction with functionalized siloxanes. In addition, the patent does not disclose or suggest the use of compounds of Formula (1P) as latent mercaptosilane coupling agents, nor does it disclose or suggest the use of these compounds in any way which would give rise to the advantages of using them as a source of latent mercaptosilane.
JP 63270751 A2 discloses the use of compounds represented by the general formula CH 2 ═C(CH 3 )C(═O)S(CH 2 ) 1-6 Si(OCH 3 ) 3 in tire tread compositions; but these compounds are not desirable because the unsaturation α,β to the carbonyl group of the thioester has the undesirable potential to polymerize during the compounding process or during storage.
There remains a need for effective latent coupling agents which exhibit the advantages of mercaptosilanes without exhibiting the disadvantages such as described herein.
SUMMARY OF THE INVENTION
The conversion of a portion of the hydrolyzable groups of the latent mercaptosilanes into siloxane bonds liberates a portion of the volatile by-products prior to the use of the coupling agents in the elastomer, via their conversion to the corresponding mercaptosiloxane coupling agents of the invention described herein. The latent mercaptosiloxane coupling agents retain the function of the latent mercaptosilanes, but with the accompaniment of lower VOC emissions and with a reduced loading level requirement.
Thioester-functional alkoxysiloxanes are introduced into the elastomer composition as the source of the coupling agents. The latent thioester group serves a dual function during the mixing process. First, it keeps the coupling agent inactive during the mixing process so as to prevent premature cure and second, it serves as a hydrophobating agent for the filler so as to enhance filler dispersion in the polymer matrix. It also serves to minimize filler re-agglomeration after the mixing process (Payne Effect). Following the mixing process, the latent thioester group is removed by a suitable deblocking agent added with the curatives. This generates the active mercapto derivative, which then chemically binds to the polymer during the curing process, thereby completing the coupling of polymer to filler.
The present invention is directed to the use of siloxane derivatives of latent mercaptosilane coupling agents, whereby VOC emissions during the elastomer compounding process are reduced. The invention also presents a way of reducing the quantity of coupling agent required for the elastomer composition.
More particularly, the present invention is directed to a blocked mercaptosilane condensate comprising at least one component whose chemical structure is represented by Formula 1:
(W1) l (W2) m (W3) y (W4) u (W5) v (W6) w Formula 1
wherein:
m, y, u, v, and w are independently any integer from zero to 10,000;
l is any integer from 1 to 10,000;
W1 is a hydrolyzable blocked mercaptosilane fragment derived from a hydrolyzable blocked mercaptosilane by replacement of at least one hydrolyzable group with one end of a siloxane oxygen (—O—) group that is represented by either Formula 2 or Formula 3:
{[(ROC(═O)—) p (G-) j ] k Y—S—} r G(—SiX 3 ) s Formula 2:
{(X 3 Si—) q G} a {Y(—S-G-SiX 3 ) b } c ; Formula 3:
W2 is a hydrolyzable mercaptosilane fragment derived from a hydrolyzable mercaptosilane by replacement of at least one hydrolyzable group with one end of a siloxane oxygen (—O—) group that is represented by Formula 4:
{[(ROC(═O)—) p (G-) j ] k Y—S—} r-d G(—SH) d (—SiX 3 ) s ; Formula 4:
W3 is a hydrolyzable polysulfide silane fragment derived from a polysulfide silane by replacement of at least one hydrolyzable group with one end of a siloxane oxygen (—O—) group that is represented by Formula 5:
X 1 X 2 X 3 Si-G 1 -S x -G 1 -SiX 1 X 2 X 3 ; Formula 5:
W4 is a hydrolyzable alkyl silane fragment derived from a hydrolyzable alkyl silane by replacement of at least one hydrolyzable group with one end of a siloxane oxygen (—O—) group that can be represented by Formula 6:
Y 1 Y 2 Y 3 Si—R 2 ; Formula 6:
W5 is a hydrolyzable bis silyl alkane fragment derived from a hydrolyzable bis silyl alkane by replacement of at least one hydrolyzable group with one end of a siloxane oxygen (—O—) group that is represented by Formula 7:
Z 1 Z 2 Z 3 Si-J-SiZ 1 Z 2 Z 3 ; Formula 7:
W6 is a hydrolyzable tris silyl alkane fragment derived from a hydrolyzable tris silyl alkane by replacement of at least one hydrolyzable group with one end of a siloxane oxygen (—O—) group that is represented by either Formula 8 or Formula 9:
(Z 1 Z 2 Z 3 Si—CH 2 CH 2 —) 3 C 6 H 9 Formula 8:
(Z 1 Z 2 Z 3 Si—CH 2 CH 2 CH 2 —) 3 N 3 C 3 O 3 ; Formula 9:
wherein, in the preceding Formulae 2 through 9:
Y is a polyvalent species (Q) z A(═E);
A is selected from the group consisting of carbon, sulfur, phosphorus, and sulfonyl;
E is selected from the group consisting of oxygen, sulfur, and NR;
each G is independently selected from the group consisting of monovalent and polyvalent moieties derived by substitution of alkyl, alkenyl, aryl, or aralkyl moieties, wherein G comprises from 1 to 18 carbon atoms; provided that G is not such that the silane would contain an α,β-unsaturated carbonyl including a carbon-carbon double bond next to the thiocarbonyl group, and provided that, if G is univalent, i.e., if p is 0, G can be hydrogen;
in each case, the atom A attached to the unsaturated heteroatom E is attached to the sulfur, which in turn is linked via a group G to the silicon atom;
Q is selected from the group consisting of oxygen, sulfur, and (—NR—);
each R is independently selected from the group consisting of hydrogen; straight, cyclic, or branched alkyl that may or may not contain unsaturation; alkenyl groups; aryl groups; and aralkyl groups, wherein each R, other than where R is hydrogen, comprises from 1 to 18 carbon atoms;
each X is independently selected from the group consisting of —Cl, —Br, RO—, RC(═O)O—, R 2 C═NO—, R 2 NO—, R 2 N—, —R, —(OSiR 2 ) t (OSiR 3 ), and (—O—) 0.5 wherein each R is as above and at least one X is not —R;
R 1 , R 2 , and R 3 are independently selected from the group consisting of hydrocarbon fragments obtained by removal of one hydrogen atom from a hydrocarbon having from 1 to 20 carbon atoms including aryl groups and any branched or straight chain alkyl, alkenyl, arenyl, or aralkyl groups;
each J, and G 1 are independently selected from the group consisting of hydrocarbon fragments obtained by removal of two hydrogen atom from a hydrocarbon having from 1 to 20 carbon atoms including arylene groups and any branched or straight chain alkylene, alkenylene, arenylene, or aralkylene groups;
each X 1 is a hydrolyzable moiety independently selected from the group consisting of —Cl, —Br, —OH, —OR 1 , R 1 C(═O)O—, —O—N═CR 1 2 , and (—O—) 0.5 ;
each X 2 and X 3 is independently selected from the group consisting of hydrogen, the members listed above for R 1 , and the members listed above for X 1 ;
at least one occurrence of X 1 , X 2 , and X 3 is (—O—) 0.5 ;
Y 1 is a moiety selected from hydrolyzable groups consisting of —Cl, —Br, —OH, —OR, R 2 C(═O)O—, —O—N═CR 2 2 , and (—O—) 0.5 ;
Y 2 and Y 3 are independently selected from the group consisting of hydrogen, the members listed above for R 2 , and the members listed above for Y 1 ; and
at least one occurrence of Y 1 , Y 2 , and Y 3 is (—O—) 0.5 .
Z 1 is selected from the hydrolyzable groups consisting of —Cl, —Br, —OH, —OR 3 , R 3 C(═O)O—, —O—N═CR 3 2 , and (—O—) 0.5 ;
Z 2 and Z 3 are independently selected from the group consisting of hydrogen, the members listed above for R 3 , and the members listed above for Z 1 ;
at least one occurrence of Z 1 , Z 2 , and Z 3 in Formula 7 is (—O—) 0.5 ;
C 6 H 9 in Formula 8 represents any cyclohexane fragment obtainable by removal of three hydrogen atoms from a cyclohexane molecule;
N 3 C 3 O 3 in Formula 9 represents N,N′,N″-trisubstituted cyanurate;
a is 0 to 7;
b is 1 to 3;
c is 1 to 6;
d is 1 to r;
j is 0 or 1, but it may be 0 if, and only if, p is 1;
k is 1 to 2;
p is 0 to 5;
q is 0 to 6;
r is 1 to 3;
s is 1 to 3;
t is 0 to 5;
x is 2 to 20;
z is 0 to 2;
provided that:
(a) if A is carbon, sulfur, or sulfonyl, then
(i) a+b is 2, and (ii) k is 1;
(b) if A is phosphorus, then a+b is 3 unless both
(i) c is greater than 1, and (ii) b is 1,
in which case a is c+1; and c) if A is phosphorus, then k is 2.
In another aspect, the present invention is directed to a composition comprising at least one organic polymer, at least one inorganic filler, and at least one blocked mercaptosilane condensate comprising at least one component whose chemical structure is represented by Formula 1:
(W1) l (W2) m (W3) y (W4) u (W5) v (W6) w Formula 1
wherein:
m, y, u, v, and w are independently any integer from zero to 10,000;
l is any integer from 1 to 10,000;
W1 is a hydrolyzable blocked mercaptosilane fragment derived from a hydrolyzable blocked mercaptosilane by replacement of at least one hydrolyzable group with one end of a siloxane oxygen (—O—) group that is represented by either Formula 2 or Formula 3:
{[(ROC(═O)—) p (G-) j ] k Y—S—} r G(—SiX 3 ) s Formula 2:
{(X 3 Si—) q G} a {Y(—S-G-SiX 3 ) b } c ; Formula 3:
W2 is a hydrolyzable mercaptosilane fragment derived from a hydrolyzable mercaptosilane by replacement of at least one hydrolyzable group with one end of a siloxane oxygen (—O—) group that is represented by Formula 4:
{[(ROC(═O)—) p (G-) j ] k Y—S—} r-d G(—SH) d (—SiX 3 ) s ; Formula 4:
W3 is a hydrolyzable polysulfide silane fragment derived from a polysulfide silane by replacement of at least one hydrolyzable group with one end of a siloxane oxygen (—O—) group that is represented by Formula 5:
X 1 X 2 X 3 Si-G 1 -S x -G 1 -SiX 1 X 2 X 3 ; Formula 5:
W4 is a hydrolyzable alkyl silane fragment derived from a hydrolyzable alkyl silane by replacement of at least one hydrolyzable group with one end of a siloxane oxygen (—O—) group that can be represented by Formula 6:
Y 1 Y 2 Y 3 Si—R 2 ; Formula 6:
W5 is a hydrolyzable bis silyl alkane fragment derived from a hydrolyzable bis silyl alkane by replacement of at least one hydrolyzable group with one end of a siloxane oxygen (—O—) group that is represented by Formula 7:
Z 1 Z 2 Z 3 Si-J-SiZ 1 Z 2 Z 3 ; Formula 7:
W6 is a hydrolyzable tris silyl alkane fragment derived from a hydrolyzable tris silyl alkane by replacement of at least one hydrolyzable group with one end of a siloxane oxygen (—O—) group that is represented by either Formula 8 or Formula 9:
(Z 1 Z 2 Z 3 Si—CH 2 CH 2 —) 3 C 6 H 9 Formula 8:
(Z 1 Z 2 Z 3 Si—CH 2 CH 2 CH 2 —) 3 N 3 C 3 O 3 ; Formula 9:
wherein, in the preceding Formulae 2 through 9:
Y is a polyvalent species (Q) z A(═E);
A is selected from the group consisting of carbon, sulfur, phosphorus, and sulfonyl;
E is selected from the group consisting of oxygen, sulfur, and NR;
each G is independently selected from the group consisting of monovalent and polyvalent moieties derived by substitution of alkyl, alkenyl, aryl, or aralkyl moieties, wherein G comprises from 1 to 18 carbon atoms; provided that G is not such that the silane would contain an α,β-unsaturated carbonyl including a carbon-carbon double bond next to the thiocarbonyl group, and provided that, if G is univalent, i.e., if p is 0, G can be hydrogen;
in each case, the atom A attached to the unsaturated heteroatom E is attached to the sulfur, which in turn is linked via a group G to the silicon atom;
Q is selected from the group consisting of oxygen, sulfur, and (—NR—);
each R is independently selected from the group consisting of hydrogen; straight, cyclic, or branched alkyl that may or may not contain unsaturation; alkenyl groups; aryl groups; and aralkyl groups, wherein each R, other than where R is hydrogen, comprises from 1 to 18 carbon atoms;
each X is independently selected from the group consisting of —Cl, —Br, RO—, RC(═O)O—, R 2 C═NO—, R 2 NO—, R 2 N—, —R, —(OSiR 2 ) t (OSiR 3 ), and (—O—) 0.5 wherein each R is as above and at least one X is not —R;
R 1 , R 2 , R 3 are independently selected from the group consisting of hydrocarbon fragments obtained by removal of one hydrogen atom from a hydrocarbon having from 1 to 20 carbon atoms including aryl groups and any branched or straight chain alkyl, alkenyl, arenyl, or aralkyl groups;
each J, and G 1 are independently selected from the group consisting of hydrocarbon fragments obtained by removal of two hydrogen atom from a hydrocarbon having from 1 to 20 carbon atoms including arylene groups and any branched or straight chain alkylene, alkenylene, arenylene, or aralkylene groups;
each X 1 is a hydrolyzable moiety independently selected from the group consisting of —Cl, —Br, —OH, —OR 1 , R 1 C(═O)O—, —O—N═CR 1 2 , and (—O—) 0.5 ;
each X 2 and X 3 is independently selected from the group consisting of hydrogen, the members listed above for R 1 , and the members listed above for X 1 ;
at least one occurrence of X 1 , X 2 , and X 3 is (—O—) 0.5 ;
Y 1 is a moiety selected from hydrolyzable groups consisting of —Cl, —Br, —OH, —OR, R 2 C(═O)O—, —O—N═CR 2 2 , and (—O—) 0.5 ;
Y 2 and Y 3 are independently selected from the group consisting of hydrogen, the members listed above for R 2 , and the members listed above for Y 1 ; and
at least one occurrence of Y 1 , Y 2 , and Y 3 is (—O—) 0.5 .
Z 1 is selected from the hydrolyzable groups consisting of —Cl, —Br, —OH, —OR 3 , R 3 C(═O)O—, —O—N═CR 3 2 , and (—O—) 0.5 ;
Z 2 and Z 3 are independently selected from the group consisting of hydrogen, the members listed above for R 3 , and the members listed above for Z 1 ;
at least one occurrence of Z 1 , Z 2 , and Z 3 in Formula 7 is (—O—) 0.5 ;
C 6 H 9 in Formula 8 represents any cyclohexane fragment obtainable by removal of three hydrogen atoms from a cyclohexane molecule;
N 3 C 3 O 3 in Formula 9 represents N,N′,N″-trisubstituted cyanurate;
a is 0 to 7;
b is 1 to 3;
c is 1 to 6;
d is 1 to r;
j is 0 or 1, but it may be 0 if, and only if, p is 1;
k is 1 to 2;
p is 0 to 5;
q is 0 to 6;
r is 1 to 3;
s is 1 to 3;
t is 0 to 5;
x is 2 to 20;
z is 0 to 2;
provided that:
(a) if A is carbon, sulfur, or sulfonyl, then
(i) a+b is 2, and (ii) k is 1;
(b) if A is phosphorus, then a+b is 3 unless both
(i) c is greater than 1, and (ii) b is 1,
in which case a is c+1; and c) if A is phosphorus, then k is 2.
In still another aspect, the present invention is directed to an article of manufacture comprising the composition described in the previous paragraph.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Silane Structures
The blocked mercaptosilane condensates described herein comprise at least one component whose chemical structure can be represented by Formula 1.
(W1) l (W2) m (W3) y (W4) u (W5) v (W6) w Formula 1
In Formula 1, m, y, u, v, and w are independently any integer from zero to 10,000; l is any integer from 1 to 10,000. Preferably, l+m+y+u+v+w is equal to at least 2.
W1, W2, W3, W4, W5, and W6 (the “W groups”) represent the building blocks of the blocked mercaptosilane condensates described herein.
In Formula 1:
W1 is a hydrolyzable blocked mercaptosilane fragment derived from a hydrolyzable blocked mercaptosilane by replacement of at least one hydrolyzable group with one end of a siloxane oxygen (—O—) group that can be represented by either Formula 2 or Formula 3:
{[(ROC(═O)—) p (G-) j ] k Y—S—} r G(—SiX 3 ) s Formula 2:
{(X 3 Si—) q G} a {Y(—S-G-SiX 3 ) b } c Formula 3:
W2 is a hydrolyzable mercaptosilane fragment derived from a hydrolyzable mercaptosilane by replacement of at least one hydrolyzable group with one end of a siloxane oxygen (—O—) group that can be represented by Formula 4:
{[(ROC(═O)—) p (G-) j ] k Y—S—} r-d G(—SH) d (—SiX 3 ) s Formula 4:
W3 is a hydrolyzable polysulfide silane fragment derived from a polysulfide silane by replacement of at least one hydrolyzable group with one end of a siloxane oxygen (—O—) group that can be represented by Formula 5:
X 1 X 2 X 3 Si-G 1 -S x -G 1 -SiX 1 X 2 X 3 Formula 5:
W4 is a hydrolyzable alkyl silane fragment derived from a hydrolyzable alkyl silane by replacement of at least one hydrolyzable group with one end of a siloxane oxygen (—O—) group that can be represented by Formula 6:
Y 1 Y 2 Y 3 Si—R 2 Formula 6:
W5 is a hydrolyzable bis silyl alkane fragment derived from a hydrolyzable bis silyl alkane by replacement of at least one hydrolyzable group with one end of a siloxane oxygen (—O—) group that can be represented by Formula 7:
Z 1 Z 2 Z 3 Si-J-SiZ 1 Z 2 Z 3 Formula 7:
W6 is a hydrolyzable tris silyl alkane fragment derived from a hydrolyzable tris silyl alkane by replacement of at least one hydrolyzable group with one end of a siloxane oxygen (—O—) group that can be represented by either Formula 8 or Formula 9:
(Z 1 Z 2 Z 3 Si—CH 2 CH 2 —) 3 C 6 H 9 Formula 8:
(Z 1 Z 2 Z 3 Si—CH 2 CH 2 CH 2 —) 3 N 3 C 3 O 3 Formula 9:
In the preceding Formulae 2 through 9:
Y is a polyvalent species (Q) z A(═E), preferably selected from the group consisting of —C(═NR)—; —SC(═NR)—; —SC(═O)—; (—NR)C(═O)—; (—NR)C(═S)—; —OC(═O)—; —OC(═S)—; —C(═O)—; —SC(═S)—; —C(═S)—; —S(═O)—; —S(═O) 2 —; —OS(═O) 2 —; (—NR)S(═O) 2 —; —SS(═O)—; —OS(═O)—; (—NR)S(═O)—; —SS(═O) 2 —; (—S) 2 P(═O)—; —(—S)P(═O)—; —P(═O)(—) 2 ; (—S) 2 P(═S)—; —(—S)P(═S)—; —P(═S)(—) 2 ; (—NR) 2 P(═O)—; (—NR)(—S)P(═O)—; (—O)(—NR)P(═O)—; (—O)(—S)P(═O)—; (—O) 2 P(═O)—; —(—O)P(═O)—; —(—NR)P(═O)—; (—NR) 2 P(═S)—; (—NR)(—S)P(═S)—; (—O)(—NR)P(═S)—; (—O)(—S)P(═S)—; (—O) 2 P(═S)—; —(—O)P(═S)—; and —(—NR)P(═S)—;
A is selected from the group consisting of carbon, sulfur, phosphorus, and sulfonyl;
E is selected from the group consisting of oxygen, sulfur, and NR;
each G is independently selected from the group consisting of monovalent and polyvalent moieties derived by substitution of alkyl, alkenyl, aryl, or aralkyl moieties, wherein G comprises from 1 to 18 carbon atoms; provided that G is not such that the silane would contain an α,β-unsaturated carbonyl including a carbon-carbon double bond next to the thiocarbonyl group, and provided that, if G is univalent (i.e., if p is 0), G can be hydrogen;
in each case, the atom (A) attached to the unsaturated heteroatom (E) is attached to the sulfur, which in turn is linked via a group G to the silicon atom;
Q is selected from the group consisting of oxygen, sulfur, and (—NR—);
each R is independently selected from the group consisting of hydrogen; straight, cyclic, or branched alkyl that may or may not contain unsaturation; alkenyl groups; aryl groups; and aralkyl groups, wherein each R, other than hydrogen, comprises from 1 to 18 carbon atoms;
each X is independently selected from the group consisting of —Cl, —Br, RO—, RC(═O)O—, R 2 C═NO—, R 2 NO—, R 2 N—, —R, —(OSiR 2 ) t (OSiR 3 ), and (—O—) 0.5 wherein each R is as above and at least one X is not —R;
R 1 , R 2 , R 3 are independently selected from the group consisting of hydrocarbon fragments obtained by removal of one hydrogen atom from a hydrocarbon having from 1 to 20 carbon atoms including aryl groups and any branched or straight chain alkyl, alkenyl, arenyl, or aralkyl groups;
each J, and G 1 are independently selected from the group consisting of hydrocarbon fragments obtained by removal of two hydrogen atom from a hydrocarbon having from 1 to 20 carbon atoms including arylene groups and any branched or straight chain alkylene, alkenylene, arenylene, or aralkylene groups;
each X 1 is a hydrolyzable moiety independently selected from the group consisting of —Cl, —Br, —OH, —OR 1 , R 1 C(═O)O—, —O—N═CR 1 2 , and (—O—) 0.5 ;
each X 2 and X 3 is independently selected from the group consisting of hydrogen, the members listed above for R 1 , and the members listed above for X 1 ;
at least one occurrence of X 1 , X 2 , and X 3 is (—O—) 0.5 ;
Y 1 is a moiety selected from hydrolyzable groups consisting of —Cl, —Br, —OH, —OR, R 2 C(═O)O—, —O—N═CR 2 2 , and (—O—) 0.5 ;
Y 2 and Y 3 are independently selected from the group consisting of hydrogen, the members listed above for R 2 , and the members listed above for Y 1 ; and
at least one occurrence of Y 1 , Y 2 , and Y 3 is (—O—) 0.5 .
Z 1 is selected from the hydrolyzable groups consisting of —Cl, —Br, —OH, —OR 3 , R 3 C(═O)O—, —O—N═CR 3 2 , and (—O—) 0.5 ;
Z 2 and Z 3 are independently selected from the group consisting of hydrogen, the members listed above for R 3 , and the members listed above for Z 1 ;
at least one occurrence of Z 1 , Z 2 , and Z 3 in Formula 7 is (—O—) 0.5 ;
C 6 H 9 in Formula 8 represents any cyclohexane fragment obtainable by removal of three hydrogen atoms from a cyclohexane molecule;
N 3 C 3 O 3 in Formula 9 represents N,N′,N″-trisubstituted cyanurate.
a is 0 to 7;
b is 1 to 3;
c is 1 to 6, preferably 1 to 4;
d is 1 to r;
j is 0 or 1, but it may be 0 if, and only if, p is 1;
k is 1 to 2;
p is 0 to 5;
q is 0 to 6;
r is 1 to 3;
s is 1 to 3;
t is 0 to 5;
x is 2 to 20;
z is 0 to 2;
provided that:
(a) if A is carbon, sulfur, or sulfonyl, then
(i) a+b is 2, and (ii) k is 1;
(b) if A is phosphorus, then a+b is 3 unless both
(i) c is greater than 1, and (ii) b is 1,
in which case a is c+1; and c) if A is phosphorus, then k is 2.
As used herein, the notation, (—O—) 0.5 , refers to one half of a siloxane bond. It is used in conjunction with a silicon atom and is taken to mean one half of an oxygen atom, namely, the half bound to the particular silicon atom. It is understood that the other half of the oxygen atom and its bond to silicon occurs somewhere else in the overall molecular structure being described. Thus, the (—O—) 0.5 siloxane groups serve as the “glue” that holds the six W components of Formula 1 together. Thus, each of the l+m+y+u+v+w W components of Formula 1 needs to have at least one (—O—) 0.5 group, shared with a silicon of another W group, for it to be a part of the overall structure, but each of these components is also free to have additional (—O—) 0.5 groups, up to the total number of hydrolyzable groups present. Moreover, the additional (—O—) 0.5 groups can each be, independently of the rest, bridged to another W group, or internal. An internal (—O—) 0.5 group is one that would bridge silicon atoms within a single W group, and could occur within a single W group if it contained more than one silicon atom.
Representative examples of the functional groups (—YS—) present in the hydrolyzable blocked mercaptosilane silane fragments of the present invention include thiocarboxylate ester, —C(═O)—S—; dithiocarboxylate, —C(═S)—S—; thiocarbonate ester, —O—C(═O)—S—; dithiocarbonate ester, —S—C(═O)—S— and —O—C(═S)—S—; trithiocarbonate ester, —S—C(═S)—S—; thiocarbamate ester, (—N—)C(═O)—S; dithiocarbamate ester, (—N—)C(═S)—S—; thiosulfonate ester, —S(═O) 2 —S—; thiosulfate ester, —O—S(═O) 2 —S—; thiosulfamate ester, (—N—)S(═O) 2 —S—; thiosulfinate ester, —S(═O)—S—; thiosulfite ester, —O—S(═O)—S—; thiosulfimate ester, (—N—)S(═O)—S—; thiophosphate ester, P(═O)(O—) 2 (S—); dithiophosphate ester, P(═O)(O—)(S—) 2 or P(═S)(O—) 2 (S—); trithiophosphate ester, P(═O)(S—) 3 or P(═S)(O—)(S—) 2 ; tetrathiophosphate ester P(═S)(S—) 3 ; thiophosphamate ester, —P(═O)(—N—)(S—); dithiophosphamate ester, —P(═S)(—N—)(S—); thiophosphoramidate ester, (—N—)P(═O)(O—)(S—); dithiophosphoramidate ester, (—N—)P(═O)(S—) 2 or (—N—)P(═S)(O—)(S—); and trithiophosphoramidate ester, (—N—)P(—S)(S—) 2 .
Preferred hydrolyzable blocked mercaptosilane silane fragments of the present invention are those wherein the Y groups are —C(═NR)—; —SC(═NR)—; —SC(═O)—; —OC(═O)—; —S(═O)—; —S(═O) 2 —; —OS(═O) 2 —; —(NR)S(═O) 2 —; —SS(═O)—; —OS(═O)—; —(NR)S(═O)—; —SS(═O) 2 —; (—S) 2 P(═O)—; —(—S)P(═O)—; —P(═O)(—) 2 ; (—S) 2 P(═S)—; —(—S)P(═S)—; —P(═S)(—) 2 ; (—NR) 2 P(═O)—; (—NR)(—S)P(═O)—; (—O)(—NR)P(═O)—; (—O)(—S)P(═O)—; (—O) 2 P(═O)—; —(—O)P(═O)—; —(—NR)P(═O)—; (—NR) 2 P(═S)—; (—NR)(—S)P(═S)—; (—O)(—NR)P(═S)—; (—O)(—S)P(═S)—; (—O) 2 P(═S)—; —(—O)P(═S)—; and —(—NR)P(═S)—. Particularly preferred are —OC(═O)—; —SC(═O)—; —S(═O)—; —OS(═O)—; —(—S)P(═O)—; and —P(═O)(—) 2 .
Another preferred hydrolyzable blocked mercaptosilane silane fragment would be one wherein Y is RC(═O)— in which R has a primary carbon attached to the carbonyl and is a C 2 -C 12 alkyl, more preferably a C 6 -C 8 alkyl.
Another preferred structure is of the form X 3 SiGSC(═O)GC(═O)SGSiX 3 wherein G is a divalent hydrocarbon.
Examples of G include —(CH 2 ) n — wherein n is 1 to 12, diethylene cyclohexane, 1,2,4-triethylene cyclohexane, and diethylene benzene. It is preferred that the sum of the carbon atoms within the G groups within the molecule are from 3 to 18, more preferably 6 to 14. This amount of carbon in the blocked mercaptosilane facilitates the dispersion of the inorganic filler into the organic polymers, thereby improving the balance of properties in the cured filled elastomer.
Preferable R groups are hydrogen, C 6 to C 10 aryl, and C 1 to C 6 alkyl.
Specific examples of X are methoxy, ethoxy, propoxy, isopropoxy, isobutoxy, acetoxy, and oximato. Methoxy, ethoxy, and acetoxy are preferred. At least one X must be reactive, i.e., hydrolyzable and at least one occurrence of X must be (—O—) 0.5 , i.e., part of a siloxane bond.
In preferred embodiments, p is 0 to 2; X is RO— or RC(═O)O—; R is hydrogen, phenyl, isopropyl, cyclohexyl, or isobutyl; and G is a substituted phenyl or substituted straight chain C 2 to C 12 alkyl. The most preferred embodiments include those wherein p is zero, X is ethoxy, and G is a C 3 -C 12 alkyl derivative.
Representative examples of the hydrolyzable blocked mercaptosilane silane fragments of the present invention include those whose parent silanes are 2-triethoxysilyl-1-ethyl thioacetate; 2-trimethoxysilyl-1-ethyl thioacetate; 2-(methyldimethoxysilyl)-1-ethyl thioacetate; 3-trimethoxysilyl-1-propyl thioacetate; triethoxysilylmethyl thioacetate; trimethoxysilylmethyl thioacetate; triisopropoxysilylmethyl thioacetate; methyldiethoxysilylmethyl thioacetate; methyldimethoxysilylmethyl thioacetate; methyldiisopropoxysilylmethyl thioacetate; dimethylethoxysilylmethyl thioacetate; dimethylmethoxysilylmethyl thioacetate; dimethylisopropoxysilylmethyl thioacetate; 2-triisopropoxysilyl-1-ethyl thioacetate; 2-(methyldietboxysilyl)-1-ethyl thioacetate; 2-(methyldiisopropoxysilyl)-1-ethyl thioacetate; 2-(dimethylethoxysilyl)-1-ethyl thioacetate; 2-(dimethylmethoxysilyl)-1-ethyl thioacetate; 2-(dimethylisopropoxysilyl)-1-ethyl thioacetate; 3-triethoxysilyl-1-propyl thioacetate; 3-triisopropoxysilyl-1-propyl thioacetate; 3-methyldiethoxysilyl-1-propyl thioacetate; 3-methyldimethoxysilyl-1-propyl thioacetate; 3-methyldiisopropoxysilyl-1-propyl thioacetate; 1-(2-triethoxysilyl-1-ethyl)-4-thioacetylcyclohexane; 1-(2-triethoxysilyl-1-ethyl)-3-thioacetylcyclohexane; 2-triethoxysilyl-5-thioacetylnorbornene; 2-triethoxysilyl-4-thioacetylnorbornene; 2-(2-triethoxysilyl-1-ethyl)-5-thloacetylnorbornene; 2-(2-triethoxysilyl-1-ethyl)-4-thioacetylnorbornene; 1-(1-oxo-2-thia-5-triethoxysilylpentyl)benzoic acid; 6-triethoxysilyl-1-hexyl thioacetate; 1-triethoxysiiyl-5-hexyl thioacetate; 8-triethoxysilyl-1-octyl thioacetate; 1-triethoxysilyl-7-octyl thioacetate; 6-triethoxysilyl-1-hexyl thioacetate;, 1-triethoxysilyl-5-octyl thioacetate; 8-trimethoxysilyl-4-octyl thioacetate; 1-trimethoxysilyl-7-octyl thioacetate; 10-triethoxysilyl-1-decyl thioacetate; 1-triethoxysilyl-9-decyl thioacetate; 1-triethoxysilyl-2-butyl thioacetate; 1-triethoxysilyl-3-butyl thioacetate; 1-triethoxysilyl-3-methyl-2-butyl thioacetate; 1-triethoxysilyl-3-methyl-3-butyl thioacetate; 3-trimethoxysilyl-1-propyl thiooctoate; 3-triethoxysilyl-1-propyl thiopalmitate; 3-triethoxysilyl-1-propyl thiooctoate; 3-triethoxysilyl-1-propyl thiobenzoate; 3-triethoxysilyl-1-propyl thio-2-ethylhexanoate; 3-methyldiacetoxysilyl-1-propyl thioacetate; 3-triacetoxysilyl-1-propyl thioacetate; 2-methyldiacetoxysilyl-1-ethyl thioacetate; 2-triacetoxysilyl-1-ethyl thioacetate; 1-methyldiacetoxysilyl-1-ethyl thioacetate; 1-triacetoxysilyl-1-ethyl thioacetate; tris-(3-triethoxysilyl-1-propyl)trithiophosphate; bis-(3-triethoxysilyl-1propyl)methyldithiophosphonate; bis-(3-triethoxysilyl-1-propyl)ethyldithiophosphonate; 3-triethoxysilyl-1-propyldimethylthiophosphinate; 3-triethoxysilyl-1-propyldiethylthiophosphinate; tris-(3-triethoxysilyl-1-propyl)tetrathiophosphate; bis-(3-triethoxysilyl-1-propyl)methyltrithiophosphonate; bis-(3-triethoxysilyl-1-propyl)ethyltrithiophosphonate; 3-triethoxysilyl-1-propyldimethyldithiophosphinate; 3-triethoxysilyl-1-propyldiethyldthiophosphinate; tris-(3-methyldimethoxysilyl-1-propyl)trithiophosphate; bis-(3-methyldimethoxysilyl-1-propyl)methyldithiophosphonate; bis-(3-methyldimethoxysilyl-1-propyl)ethyldithiophosphonate; 3-methyldimethoxysilyl-1-propyldimethylthiophosphinate; 3-methyldimethoxysilyl-1-propyldiethylthiophosphinate; 3-triethoxysilyl-1-propylmethylthiosulphate; 3-triethoxysilyl-1-propylmethanethiosulphonate; 3-triethoxysilyl-1-propylethanethiosulphonate; 3-triethoxysilyl-1-propylbenzenethiosulpbonate; 3-triethoxysilyl-1-propyltoluenethiosulphonate; 3-triethoxysilyl-1-propylnaphthalenethiosulphonate; 3-triethoxysilyl-1-propylxylenethiosulphonate; triethoxysilylmethylmethylthiosulphate; triethoxysilylmethylmethanethiosulphonate; triethoxysilylmethylethanethiosulphonate; triethoxysilylmethylbenzenethiosulphonate; triethoxysilylmethyltoluenethiosulphonate; triethoxysilylmethylnaphthalenethiosulphonate; triethoxysilylmethylxylenethiosulphonate.
Representative examples of X 1 , Y 1 , and Z 1 include methoxy, ethoxy, propoxy, isopropoxy, butoxy, phenoxy, benzyloxy, hydroxy, chloro, and acetoxy. Methoxy, ethoxy, and isopropoxy are preferred. Ethoxy is most preferred.
Representative examples of X 2 , X 3 , Y 2 , Y 3 , Z 2 , and Z 3 include the representative examples listed above for X 1 as well as hydrogen, methyl, ethyl, propyl, isopropyl, sec-butyl, phenyl, vinyl, cyclohexyl, and higher, e.g., C 4 -C 20 , straight-chain alkyl, such as butyl, hexyl, octyl, lauryl, and octadecyl. Methoxy, ethoxy, isopropoxy, methyl, ethyl, phenyl, and the higher straight-chain alkyls are preferred. Ethoxy, methyl, and phenyl are most preferred.
Preferred embodiments also include those in which X 1 , X 2 , and X 3 ; Y 1 , Y 2 , and Y 3 ; and Z 1 , Z 2 , and Z 3 are the same alkoxy group, preferably methoxy, ethoxy, or isopropoxy; more preferably, ethoxy.
Representative examples of G 1 include the terminal straight-chain alkyls further substituted terminally at the other end, such as —CH 2 —, —CH 2 CH 2 —, —CH 2 CH 2 CH 2 —, and —CH 2 CH 2 CH 2 CH 2 CH 2 CH 2 CH 2 CH 2 —, and their beta-substituted analogs, such as —CH 2 (CH 2 ) m CH(CH 3 )—, where m is zero to 17; —CH 2 CH 2 C(CH 3 ) 2 CH 2 —; the structure derivable from methallyl chloride, —CH 2 CH(CH 3 )CH 2 —; any of the structures derivable from divinylbenzene, such as —CH 2 CH 2 (C 6 H 4 )CH 2 CH 2 — and —CH 2 CH 2 (C 6 H 4 )CH(CH 3 )—, where the notation C 6 H 4 denotes a disubstituted benzene ring; any of the structures derivable from butadiene, such as —CH 2 CH 2 CH 2 CH 2 —, —CH 2 CH 2 CH(CH 3 )—, and —CH 2 CH(CH 2 CH 3 )—; any of the structures derivable from piperylene, such as —CH 2 CH 2 CH 2 CH(CH 3 )—, —CH 2 CH 2 CH(CH 2 CH 3 )—, and —CH 2 CH(CH 2 CH 2 CH 3 )—; any of the structures derivable from isoprene, such as —CH 2 CH(CH 3 )CH 2 CH 2 —, —CH 2 CH(CH 3 )CH(CH 3 )—, —CH 2 C(CH 3 )(CH 2 CH 3 )—, —CH 2 CH 2 CH(CH 3 )CH 2 —, —CH 2 CH 2 C(CH 3 ) 2 —, and —CH 2 CH{CH(CH 3 ) 2 }—; any of the isomers of —CH 2 CH 2 -norbornyl- or —CH 2 CH 2 -cyclohexyl-; any of the diradicals obtainable from norbornane, cyclohexane, cyclopentane, tetrahydrodicyclopentadiene, or cyclododecene by loss of two hydrogen atoms; the structures derivable from limonene, —CH 2 CH(4-methyl-1-C 6 H 9 —)CH 3 , where the notation C 6 H 9 denotes isomers of the trisubstituted cyclohexane ring lacking substitution in the 2 position; any of the monovinyl-containing structures derivable from trivinylcyclohexane, such as —CH 2 CH 2 (vinylC 6 H 9 )CH 2 CH 2 — and —CH 2 CH 2 (vinylC 6 H 9 )CH(CH 3 )—, where the notation C 6 H 9 denotes any isomer of the trisubstituted cyclohexane ring; any of the monounsaturated structures derivable from myrcene containing a trisubstituted C═C, such as —CH 2 CH{CH 2 CH 2 CH═C(CH 3 ) 2 }CH 2 CH 2 —, —CH 2 CH{CH 2 CH 2 CH═C(CH 3 ) 2 }CH(CH 3 )—, —CH 2 C{CH 2 CH 2 CH═C(CH 3 ) 2 }(CH 2 CH 3 )—, —CH 2 CH 2 CH{CH 2 CH 2 CH═C(CH 3 ) 2 }CH 2 —, —CH 2 CH 2 (C—)(CH 3 ){CH 2 CH 2 CH═C(CH 3 ) 2 }, and —CH 2 CH{CH(CH 3 )[CH 2 CH 2 CH═C(CH 3 ) 2 ]}—; and any of the monounsaturated structures derivable from myrcene lacking a trisubstituted C═C, such as —CH 2 CH(CH═CH 2 )CH 2 CH 2 C 2 C(CH 3 ) 2 —, —CH 2 CH(CH═CH 2 )CH 2 CH 2 CH{CH(CH 3 ) 2 }—, —CH 2 C(═CH—CH 3 )CH 2 CH 2 CH 2 C(CH 3 ) 2 —, —CH 2 C(═CH—CH 3 )CH 2 CH 2 CH{CH(CH 3 ) 2 }—, —CH 2 CH 2 C(═CH 2 )CH 2 CH 2 CH 2 C(CH 3 ) 2 —, —CH 2 CH 2 C(═CH 2 )CH 2 CH 2 CH{CH(CH 3 ) 2 }—, —CH 2 CH═C(CH 3 ) 2 CH 2 CH 2 CH 2 C(CH 3 ) 2 —, and —CH 2 CH═C(CH 3 ) 2 CH 2 CH 2 CH{CH(CH 3 ) 2 }. The preferred structures for G 1 are —CH 2 —, —CH 2 CH 2 —, —CH 2 CH 2 CH 2 —, CH 2 CH(CH 3 )CH 2 —, and any of the diradicals obtained by 2,4 or 2,5 disubstitution of the norbornane-derived structures listed above. —CH 2 CH 2 CH 2 — is most preferred.
Representative examples of R 2 include methyl, vinyl, ethyl, propyl, allyl, butyl, methallyl, pentyl, hexyl, phenyl, tolyl, benzyl, octyl, xylyl, mesityl, decyl, dodecyl, hexadecyl, octadecyl, and the like. Methyl, vinyl, propyl, phenyl, octyl, and octadecyl are preferred.
Representative examples of J include the terminal straight-chain alkyls further substituted terminally at the other end, such as —CH 2 CH 2 —, —CH 2 CH 2 CH 2 —, and —CH 2 CH 2 CH 2 CH 2 CH 2 CH 2 CH 2 CH 2 —; —CH 2 CH 2 C(CH 3 ) 2 CH 2 —; the divinylbenzene derivative, —CH 2 CH 2 (C 6 H 4 )CH 2 CH 2 —, wherein the notation C 6 H 4 denotes a disubstituted benzene ring; the butadiene derivative, —CH 2 CH 2 CH 2 CH 2 —; the isoprene derivative, —CH 2 CH(CH 3 )CH 2 CH 2 —; any of the isomers of —CH 2 CH 2 -norbornyl-, and —CH 2 CH 2 -cyclohexyl-; any of the monovinyl-containing structures derivable from trivinylcyclohexane, including the isomers of —CH 2 CH 2 (vinylC 6 H 9 )CH 2 CH 2 —, where the notation C 6 H 9 denotes any isomer of the trisubstituted cyclohexane ring; and any of the monounsaturated structures derivable from myrcene, such as —CH 2 CH[CH 2 CH 2 CH═C(CH 3 ) 2 ]CH 2 CH 2 — and —CH 2 CH 2 CH[CH 2 CH 2 CH═C(CH 3 ) 2 ]CH 2 —. The preferred structures for J are —CH 2 CH 2 —, —CH 2 (CH 2 ) p CH 2 — (in which p is an even integer of from 2 to 18), and any of the diradicals obtained by 2,4 or 2,5 disubstitution of the norbornane-derived structures listed above. —CH 2 CH 2 — is most preferred.
As used herein, the term “alkyl” includes straight, branched, and cyclic alkyl groups; the term “alkenyl” includes any straight, branched, or cyclic alkenyl group containing one or more carbon-carbon double bonds, where the point of substitution can be either at a carbon-carbon double bond or elsewhere in the group; and the term “alkynyl” includes any straight, branched, or cyclic alkynyl group containing one or more carbon-carbon triple bonds and, optionally, also one or more carbon-carbon double bonds as well, where the point of substitution can be either at a carbon-carbon triple bond, a carbon-carbon double bond, or elsewhere in the group.
Specific examples of alkyls include methyl, ethyl, propyl, isobutyl, and the like. Specific examples of alkenyls include vinyl, propenyl, allyl, methallyl, ethylidenyl norbornane, ethylidene norbornyl, ethylidenyl norbornene, ethylidene norbornenyl, and the like. Specific examples of alkynyls include acetylenyl, propargyl, methylacetylenyl, and the like.
As used herein, the term “aryl” includes any aromatic hydrocarbon from which one hydrogen atom has been removed; the term “aralkyl” includes any of the aforementioned alkyl groups in which one or more hydrogen atoms has been substituted by the same number of like and/or different aryl (as defined herein) substituents; and the term “arenyl” includes any of the aforementioned aryl groups in which one or more hydrogen atoms have been substituted by the same number of like and/or different alkyl (as defined herein) substituents.
Specific examples of aryls include phenyl, naphthalenyl, and the like. Specific examples of aralkyls include benzyl, phenethyl, and the like. Specific examples of arenyls include tolyl, xylyl, and the like.
As used herein, the terms “cyclic alkyl”, “cyclic alkenyl”, and “cyclic alkynyl” also include bicyclic, tricyclic, and higher cyclic structures, as well as the aforementioned cyclic structures further substituted with alkyl, alkenyl, and/or alkynyl groups. Representive examples include norbornyl, norbornenyl, ethylnorbornyl, ethylnorbornenyl, ethylcyclohexyl, ethylcyclohexenyl, cyclohexylcyclohexyl, cyclododecatrienyl, and the like.
Preparation of Silanes
The blocked mercaptosilane condensates described herein are most easily prepared by hydrolysis and condensation of blocked mercaptosilanes in the presence of the other hydrolyzable silane types described above. Water can be added as such, or prepared by an appropriate in situ technique. Acid or base catalysts can be added to increase the rate of product formation.
The blocked mercaptosilane condensates can be prepared in a single hydrolysis/condensation step or in several such steps carried out in any combination sequentially and/or in parallel. Thus, a single step method would involve the addition of water to a blend of the hydrolyzable silanes desired in the final product. Alternatively, intermediate compositions could be prepared by the stepwise addition of water to separate individual blends of hydrolyzable silanes, optionally also containing previously prepared hydrolyzates and/or condensates. The intermediate compositions could then be used in subsequent hydrolysis/condensation steps until the final desired composition is obtained.
An example of an in situ technique for the generation of water involves the reaction of formic acid with an alkoxysilane. In this method, a formate ester and water are produced. The water then reacts further to hydrolyze and condense the hydrolyzable silanes, forming the siloxane bonds.
The blocked mercaptosilane condensates can also be prepared directly from condensates of silanes that represent appropriate starting materials for the blocked mercaptosilanes, using analogous techniques that are useful for the preparation of the blocked mercaptosilanes. Thus, the preparations employed for the syntheses of the blocked mercaptosilanes would be used, but with the substitution of condensates of the hydrolyzable silane starting materials for the silane starting materials used in the original syntheses of the blocked mercaptosilanes. These synthetic techniques are described extensively and in detail in U.S. application Ser. No. 09/284,841 filed Apr. 21, 1999.
Specifically, the methods of preparation for blocked mercaptosilanes can involve esterification of sulfur in a sulfur-containing silane and direct incorporation of the thioester group in a silane, either by substitution of an appropriate leaving group or by addition across a carbon-carbon double bond. Illustrative examples of synthetic procedures for the preparation of thioester silanes would include:
Reaction 1) the reaction between a mercaptosilane and an acid anhydride corresponding to the thioester group present in the desired product; Reaction 2) reaction of an alkali metal salt of a mercaptosilane with the appropriate acid anhydride or acid halide; Reaction 3) the transesterification between a mercaptosilane and an ester, optionally using any appropriate catalyst such as an acid, base, tin compound, titanium compound, transition metal salt, or a salt of the acid corresponding to the ester; Reaction 4) the transesterification between a thioester silane and another ester, optionally using any appropriate catalyst such as an acid, base, tin compound, titanium compound, transition metal salt, or a salt of the acid corresponding to the ester; Reaction 5) the transesterification between a 1-sila-2-thiacyclopentane or a 1-sila-2-thiacyclohexane and an ester, optionally using any appropriate catalyst such as an acid, base, tin compound, titanium compound, transition metal salt, or a salt of the acid corresponding to the ester; Reaction 6) the free radical addition of a thioacid across a carbon-carbon double bond of an alkene-functional silane, catalyzed by UV light, heat, or the appropriate free radical initiator wherein, if the thioacid is a thiocarboxylic acid, the two reagents are brought into contact with each other in such a way as to ensure that whichever reagent is added to the other is reacted substantially before the addition proceeds; and Reaction 7) the reaction between an alkali metal salt of a thioacid with a haloalkylsilane.
Acid halides include but are not limited to, in addition to organic acid halides, inorganic acid halides such as POT 3 , SOT 2 , SO 2 T 2 , COT 2 , CST 2 , PST 3 and PT 3 , wherein T is a halide. Acid anhydrides include but are not limited to, in addition to organic acid anhydrides (and their sulfur analogs), inorganic acid anhydrides such as SO 3 , SO 2 , P 2 O 3 , P 2 S 3 , H 2 S 2 O 7 , CO 2 , COS, and CS 2 .
Illustrative examples of synthetic procedures for the preparation of thiocarboxylate-functional silanes would include:
Reaction 8) the reaction between a mercaptosilane and a carboxylic acid anhydride corresponding to the thiocarboxylate group present in the desired product; Reaction 9) reaction of an alkali metal salt of a mercaptosilane with the appropriate carboxylic acid anhydride or acid halide; Reaction 10) the transesterification between a mercaptosilane and a carboxylate ester, optionally using any appropriate catalyst such as an acid, base, tin compound, titanium compound, transition metal salt, or a salt of the acid corresponding to the carboxylate ester; Reaction 11) the transesterification between a thiocarboxylate-functional silane and another ester, optionally using any appropriate catalyst such as an acid, base, tin compound, titanium compound, transition metal salt, or a salt of the acid corresponding to the other ester; Reaction 12) the transesterification between a 1-sila-2-thiacyclopentane or a 1-sila-2-thiacyclohexane and a carboxylate ester, optionally using any appropriate catalyst such as an acid, base, tin compound, titanium compound, transition metal salt, or a salt of the acid corresponding to the carboxylate ester; Reaction 13) the free radical addition of a thiocarboxylic acid across a carbon-carbon double bond of an alkene-functional silane, catalyzed by UV light, heat, or the appropriate free radical initiator; and Reaction 14) the reaction between an alkali metal salt of a thiocarboxylic acid with a haloalkylsilane.
Reactions 1 and 8 can be carried out by distilling a mixture of the mercaptosilane and the acid anhydride and, optionally, a solvent. Appropriate boiling temperatures of the mixture are in the range of 50° to 250° C., preferably 60° to 200° C., more preferably 70° to 170° C. This process leads to a chemical reaction in which the mercapto group of the mercaptosilane is esterified to the thioester silane analog with release of an equivalent of the corresponding acid. The acid typically is more volatile than the acid anhydride. The reaction is driven by the removal of the more volatile acid by distillation. For the more volatile acid anhydrides, such as acetic anhydride, the distillation preferably is carried out at atmospheric pressure to reach temperatures sufficient to drive the reaction toward completion. For less volatile materials, solvents, such as toluene, xylene, glyme, and diglyme, could be used with the process to limit temperature. Alternatively, the process could be run under reduced pressure. It would be useful to use up to a twofold excess or more of the acid anhydride, which would be distilled out of the mixture after all of the more volatile reaction co-products, comprising acids and nonsilane esters, have been distilled out. This excess of acid anhydride would serve to drive the reaction to completion, as well as to help drive the co-products out of the reaction mixture. At the completion of the reaction, distillation should be continued to drive out the remaining acid anhydride. Optionally, the product could be distilled.
Reactions 2 and 9 can be carried out in two steps.
The first step would involve conversion of the mercaptosilane to a corresponding metal derivative. Alkali metal derivatives, especially sodium, but also potassium and lithium, are preferable. The alkali metal derivative would be prepared by adding the alkali metal or a strong base derived from the alkali metal to the mercaptosilane. The reaction would occur at ambient temperature. Appropriate bases would include alkali metal alkoxides, amides, hydrides, and mercaptides. Alkali metal organometallic reagents would also be effective. Grignard reagents would yield magnesium derivatives, which would be another alternative. Solvents, such as toluene, xylene, benzene, aliphatic hydrocarbons, ethers, and alcohols, could be used to prepare the alkali metal derivatives. Once the alkali metal derivative is prepared, any alcohol present must be removed. This could be done by distillation or evaporation. Alcohols, such as methanol, ethanol, propanol, isopropanol, butanol, isobutanol, and t-butanol, may be removed by azeotropic distillation with benzene, toluene, xylene, or aliphatic hydrocarbons. Toluene and xylene are preferred; toluene is most preferred.
The second step in the overall process would be to add to this solution, with stirring, the acid chloride or acid anhydride at temperatures between −20° C. and the boiling point of the mixture, preferably at temperatures between 0° C. and ambient temperature. The product would be isolated by removing the salt and solvent. It could be purified by distillation.
Reactions 3 and 10 could be carried out by distilling a mixture of the mercaptosilane and the ester and, optionally, a solvent and/or a catalyst. Appropriate boiling temperatures of the mixture would be above 100° C. This process leads to a chemical reaction in which the mercapto group of the mercaptosilane is esterified to the thioester silane analog with release of an equivalent of the corresponding alcohol. The reaction is driven by the removal of the alcohol by distillation, either as the more volatile species, or as an azeotrope with the ester. For the more volatile esters, the distillation is suitably carried out at atmospheric pressure to reach temperatures sufficient to drive the reaction toward completion. For less volatile esters, solvents, such as toluene, xylene, glyme, and diglyme, could be used with the process to limit temperature. Alternatively, the process could be run at reduced pressure. It is useful to use up to a twofold excess or more of the ester, which would be distilled out of the mixture after all of the alcohol co-product has been distilled out. This excess ester would serve to drive the reaction to completion as well as to help drive the co-product alcohol out of the reaction mixture. At the completion of the reaction, distillation would be continued to drive out the remaining ester. Optionally, the product could be distilled.
Reactions 4 and 11 could be carried out by distilling a mixture of the thioester silane and the other ester and, optionally, a solvent and/or a catalyst. Appropriate boiling temperatures of the mixture would be above 80° C.; preferably above 100° C. The temperature would preferably not exceed 250° C. This process leads to a chemical reaction in which the thioester group of the thioester silane is transesterified to a new thioester silane with release of an equivalent of a new ester. The new thioester silane generally would be the least volatile species present. However, the new ester would be more volatile than the other reactants. The reaction would be driven by the removal of the new ester by distillation. The distillation can be carried out at atmospheric pressure to reach temperatures sufficient to drive the reaction toward completion. For systems containing only less volatile materials, solvents, such as toluene, xylene, glyme, and diglyme, could be used with the process to limit temperature. Alternatively, the process could be run at reduced pressure. It would be useful to use up to a twofold excess or more of the other ester, which would be distilled out of the mixture after all of the new ester co-product has been distilled out. This excess other ester would serve to drive the reaction to completion as well as to help drive the co-product other ester out of the reaction mixture. At the completion of the reaction, distillation would be continued to drive out the remaining new ester. Optionally, the product then could be distilled.
Reactions 5 and 12 could be carried out by heating a mixture of the 1-sila-2-thiacyclopentane or the 1-sila-2-thiacyclohexane and the ester with the catalyst. Optionally, the mixture could be heated or refluxed with a solvent, preferably a solvent whose boiling point matches the desired temperature. Optionally, a solvent of higher boiling point than the desired reaction temperature can be used at reduced pressure, the pressure being adjusted to bring the boiling point down to the desired reaction temperature. The temperature of the mixture would be in the range of 80° to 250° C.; preferably 100° to 200° C. Solvents, such as toluene, xylene, aliphatic hydrocarbons, and diglyme, could be used with the process to adjust the temperature. Alternatively, the process could be run under reflux at reduced pressure. The most preferred condition is to heat a mixture of the 1-sila-2-thiacyclopentane or the 1-sila-2-thiacyclohexane and the ester without solvent, preferably under an inert atmosphere, for a period of 20 to 100 hours at a temperature of 120° to 170° C. using the sodium, potassium, or lithium salt of the acid corresponding to the ester as a catalyst. The process leads to a chemical reaction in which the sulfur-silicon bond of the 1-sila-2-thiacyclopentane or the 1-sila-2-thiacyclohexane is transesterified by addition of the ester across said sulfur-silicon bond. The product is the thioester silane analog of the original 1-sila-2-thiacyclopentane or the 1-sila-2-thiacyclohexane. Optionally, up to a twofold excess or more of the ester would be used to drive the reaction toward completion. At the completion of the reaction, the excess ester can be removed by distillation. Optionally, the product could be purified by distillation.
Reactions 6 and 13 can be carried out by heating or refluxing a mixture of the alkene-functional silane and the thioacid. Aspects of Reaction 13 have been disclosed previously in U.S. Pat. No. 3,692,812 and by G. A. Gornowicz et al., in J. Org. Chem . (1968), 33(7), 2918-24. The uncatalyzed reaction can occur at temperatures as low as 105° C., but often fails. The probability of success increases with temperature and becomes high when the temperature exceeds 160° C. The reaction may be made reliable and the reaction brought largely to completion by using UV radiation or a catalyst. With a catalyst, the reaction can be made to occur at temperatures below 90° C. Appropriate catalysts are free radical initiators, e.g., peroxides, preferably organic peroxides, and azo compounds.
Examples of peroxide initiators include peracids, such as perbenzoic and peracetic acids; esters of peracids; hydroperoxides, such as t-butyl hydroperoxide; peroxides, such as di-t-butyl peroxide; and peroxy-acetals and ketals, such as 1,1-bis(t-butylperoxy)cyclohexane; or any other peroxide.
Examples of azo initiators include azobisisobutyronitrile (AIBN), 1,1-azobis(cyclohexanecarbonitrile) (VAZO, DuPont product), and azo-tert-butane. The reaction can be run by heating a mixture of the alkene-functional silane and the thioacid with the catalyst. It is preferred that the overall reaction be run on an equimolar or near equimolar basis to get the highest conversions. The reaction is sufficiently exothermic that it tends to lead to a rapid temperature increase to reflux followed by a vigorous reflux as the reaction initiates and continues rapidly. This vigorous reaction can lead to hazardous boil-overs for larger quantities. Side reactions, contamination, and loss in yield can result as well from uncontrolled reactions. The reaction can be controlled effectively by adding partial quantities of one reagent to the reaction mixture, initiating the reaction with the catalyst, allowing the reaction to run its course largely to completion, and then adding the remains of the reagent, either as a single addition or as multiple additives. The initial concentrations and rate of addition and number of subsequent additions of the deficient reagent depend on the type and amount of catalyst used, the scale of the reaction, the nature of the starting materials, and the ability of the apparatus to absorb and dissipate heat. A second way of controlling the reaction would involve the continuous addition of one reagent to the other with concomitant continuous addition of catalyst. Whether continuous or sequential addition is used, the catalyst can be added alone and/or pre-blended with one or both reagents or combinations thereof.
Two methods are preferred for reactions involving thiolacetic acid and alkene-functional silanes containing terminal carbon-carbon double bonds. The first involves initially bringing the alkene-functional silane to a temperature of 160° to 180° C., or to reflux, whichever temperature is lower. The first portion of thiolacetic acid is added at a rate so as to maintain up to a vigorous, but controlled, reflux. For alkene-functional silanes with boiling points above 100° to 120° C., this reflux results largely from the relatively low boiling point of thiolacetic acid (88° to 92° C., depending on purity) relative to the temperature of the alkene-functional silane. At the completion of the addition, the reflux rate rapidly subsides. It often accelerates again within several minutes, especially if an alkene-functional silane with a boiling point above 120° C. is used, as the reaction initiates. If it does not initiate within 10 to 15 minutes, initiation can be brought about by addition of catalyst. The preferred catalyst is di-t-butyl peroxide. The appropriate quantity of catalyst is from 0.2 to 2 percent, preferably from 0.5 to 1 percent, of the total mass of mixture to which the catalyst is added. The reaction typically initiates within a few minutes as evidenced by an increase in reflux rate. The reflux temperature gradually increases as the reaction proceeds. Then, the next portion of thiolacetic acid is added, and the aforementioned sequence of steps is repeated. The preferred number of thiolacetic additions for total reaction quantities of about one to about four kilograms is two, with about one-third of the total thiolacetic acid used in the first addition and the remainder in the second. For total quantities in the range of about four to ten kilograms, a total of three thiolacetic additions is preferred, the distribution being approximately 20 percent of the total used in the first addition, approximately 30 percent in the second addition, and the remainder in the third addition. For larger scales involving thiolacetic acid and alkene-functional silanes, it is preferred to use more than a total of three thiolacetic additions and more preferably, to add the reagents in the reverse order. Initially, the total quantity of thiolacetic acid is brought to reflux. This is followed by continuous addition of the alkene-functional silane to the thiolacetic acid at such a rate as to bring about a smooth but vigorous reaction rate. The catalyst, preferably di-t-butylperoxide, can be added in small portions during the course of the reaction or as a continuous flow. It is best to accelerate the rate of catalyst addition as the reaction proceeds to completion to obtain the highest yields of product for the lowest amount of catalyst required. The total quantity of catalyst used should be 0.5 percent to 2 percent of the total mass of reagents used. Whichever method is used, the reaction is followed up by a vacuum stripping process to remove volatiles and unreacted thiolacetic acid and silane. The product may be purified by distillation.
Methods to run Reactions 7 and 14 can be carried out in two steps.
The first step involves preparation of a salt of the thioacid. Alkali metal derivatives are preferred, with the sodium derivative being most preferred. These salts would be prepared as solutions in solvents in which the salt is appreciably soluble, but suspension of the salts as solids in solvents in which the salts are only slightly soluble is also a viable option. Alcohols, such as propanol, isopropanol, butanol, isobutanol, and t-butanol, and preferably methanol and ethanol are useful because the alkali metal salts are slightly soluble in them. In cases where the desired product is alkoxysilanes, it is preferable to use an alcohol corresponding to the silane alkoxy group to prevent transesterification at the silicon ester. Alternatively, nonprotic solvents can be used. Examples of appropriate solvents are ethers or polyethers, such as glyme, diglyme, and dioxanes; N′N-dimethylformamide; N′N-dimethylacetamide; dimethylsulfoxide; N-methylpyrrolidinone; or hexamethylphosphoramide.
Once a solution, suspension, or combination thereof of the salt of the thioacid has been prepared, the second step is to react it with the appropriate haloalkylsilane. This may be accomplished by stirring a mixture of the haloalkylsilane with the solution, suspension, or combination thereof of the salt of the thioacid at temperatures corresponding to the liquid range of the solvent for a period of time sufficient to complete substantially the reaction. Preferred temperatures are those at which the salt is appreciably soluble in the solvent and at which the reaction proceeds at an acceptable rate without excessive side reactions. With reactions starting from chloroalkylsilanes in which the chlorine atom is not allylic or benzylic, preferred temperatures are in the range of 60° to 160° C. Reaction times can range from one or several hours to several days. For alcohol solvents where the alcohol contains four carbon atoms or fewer, the most preferred temperature is at or near reflux. With diglyme used as a solvent, the most preferred temperature is in the range of 70° to 120° C., depending upon the thioacid salt used. If the haloalkylsilane is a bromoalkylsilane or a chloroalkylsilane in which the chlorine atom is allylic or benzylic, temperature reductions of 30° to 60° C. are appropriate relative to those appropriate for nonbenzylic or nonallylic chloroalkylsilanes because of the greater reactivity of the bromo group. Bromoalkylsilanes are preferred over chloroalkylsilanes because of their greater reactivity, lower required temperatures, and greater ease in filtration or centrifugation of the co-product alkali metal halide. This preference, however, can be overridden by the lower cost of the chloroalkylsilanes, especially for those containing the halogen in the allylic or benzylic position. For reactions between straight chain chloroalkylethoxysilanes and sodium thiocarboxylates to form thiocarboxylate ester ethoxysilanes, it is preferred to use ethanol at reflux for 10 to 20 hours if 5 percent to 20 percent mercaptosilane is acceptable in the product. Otherwise, diglyme would be an excellent choice, in which the reaction would be run preferably in the range of 80° to 120° C. for one to three hours. Upon completion of the reaction, the salts and solvent should be removed, and the product may be distilled to achieve higher purity.
If the salt of the thioacid to be used in Reactions 7 and 14 is not commercially available, it may be prepared by one of two methods, described below as Method A and Method B.
Method A involves adding the alkali metal or a base derived from the alkali metal to the thioacid. The reaction occurs at ambient temperature. Appropriate bases include alkali metal alkoxides, hydrides, carbonate, and bicarbonate. Solvents, such as toluene, xylene, benzene, aliphatic hydrocarbons, ethers, and alcohols, may be used to prepare the alkali metal derivatives.
In Method B, acid chlorides or acid anhydrides would be converted directly to the salt of the thioacid by reaction with the alkali metal sulfide or hydrosulfide. Hydrated or partially hydrous alkali metal sulfides or hydrosulfides are available. However, anhydrous or nearly anhydrous alkali metal sulfides or hydrosulfides are preferred. Hydrous materials can be used, however, but with loss in yield and hydrogen sulfide formation as a co-product. The reaction involves addition of the acid chloride or acid anhydride to the solution or suspension of the alkali metal sulfide and/or hydrosulfide and heating at temperatures ranging from ambient to the reflux temperature of the solvent for a period of time sufficiently long to complete the reaction, as evidenced by the formation of the co-product salts.
If the alkali metal salt of the thioacid is prepared in such a way that an alcohol is present, either because it was used as a solvent, or because it formed, as for example, by the reaction of a thioacid with an alkali metal alkoxide, it may be desirable to remove the alcohol if a product low in mercaptosilane is desired. In this case, it would be necessary to remove the alcohol prior to reaction of the salt of the thioacid with the haloalkylsilane. This could be done by distillation or evaporation. Alcohols, such as methanol, ethanol, propanol, isopropanol, butanol, isobutanol, and t-butanol, are preferably removed by azeotropic distillation with benzene, toluene, xylene, or aliphatic hydrocarbons. Toluene and xylene are preferred.
Use of Silanes in Elastomer
The blocked mercaptosilane condensates described herein are useful as coupling agents in mineral filled elastomer compositions as previously described for blocked mercaptosilanes. Among the advantages in the use of the blocked mercaptosilane condensates over the use of the previously described blocked mercaptosilanes are the release of less volatile organic compounds (VOC), mainly ethanol, during the elastomer compounding process, as well as a lower coupling agent loading requirement. Details of their use are analogous to those of the use of blocked mercaptosilanes, previously described in U.S. application Ser. No. 09/284,841, filed Apr. 21, 1999; U.S. Pat. No. 6,127,468; and U.S. application Ser. No. 09/736,301, filed Dec. 15, 2000.
More specifically, the blocked mercaptosilane condensates described herein are useful as coupling agents for organic polymers (e.g., elastomers) and inorganic fillers. By virtue of their use, the high efficiency of the mercapto group can be utilized without the detrimental side effects typically associated with the use of mercaptosilanes, such as high processing viscosity, less than desirable filler dispersion, premature curing (scorch), and odor. These benefits are accomplished because the mercaptan group initially is non-reactive because of the blocking group. The blocking group substantially prevents the silane from coupling to the organic polymer during the compounding of the rubber. Generally, only the reaction of the silane —SiX 3 group with the filler can occur at this stage of the compounding process. Thus, substantial coupling of the filler to the polymer is precluded during mixing, thereby minimizing the undesirable premature curing (scorch) and the associated undesirable increase in viscosity. One can achieve better cured filled rubber properties, such as a balance of high modulus and abrasion resistance, because of the avoidance of premature curing.
In use, one or more of the blocked mercaptosilane condensates is mixed with the organic polymer before, during, or after the compounding of the filler into the organic polymer. It is preferred to add the silanes before or during the compounding of the filler into the organic polymer, because these silanes facilitate and improve the dispersion of the filler. The total amount of silane present in the resulting combination should be about 0.05 to about 25 parts by weight per hundred parts by weight of organic polymer (phr); more preferably 1 to 10 phr. Fillers can be used in quantities ranging from about 5 to about 100 phr, more preferably from 25 to 80 phr.
When reaction of the mixture to couple the filler to the polymer is desired, a deblocking agent is added to the mixture to deblock the blocked mercaptosilane condensate. The deblocking agent may be added at quantities ranging from about 0.1 to about 5 phr; more preferably in the range of from 0.5 to 3 phr. The deblocking agent may be a nucleophile containing a hydrogen atom sufficiently labile such that hydrogen atom could be transferred to the site of the original blocking group to form the mercaptosilane. Thus, with a blocking group acceptor molecule, an exchange of hydrogen from the nucleophile would occur with the blocking group of the blocked mercaptosilane to form the mercaptosilane and the corresponding derivative of the nucleophile containing the original blocking group. This transfer of the blocking group from the silane to the nucleophile could be driven, for example, by a greater thermodynamic stability of the products (mercaptosilane and nucleophile containing the blocking group) relative to the initial reactants (blocked mercaptosilane and nucleophile). For example, carboxyl blocking groups deblocked by amines would yield amides, sulfonyl blocking groups deblocked by amines would yield sulfonamides, sulfinyl blocking groups deblocked by amines would yield sulfinamides, phosphonyl blocking groups deblocked by amines would yield phosphonamides, phosphinyl blocking groups deblocked by amines would yield phosphinamides. What is important is that regardless of the blocking group initially present on the blocked mercaptosilane and regardless of the deblocking agent used, the initially substantially inactive (from the standpoint of coupling to the organic polymer) blocked mercaptosilane is substantially converted at the desired point in the rubber compounding procedure to the active mercaptosilane. It is noted that partial amounts of the nucleophile may be used (i.e., a stoichiometric deficiency), or even weak nucleophile, if one were to only deblock part of the blocked mercaptosilane to control the degree of vulcanization of a specific formulation.
The deblocking agent could be added in the curative package or, alternatively, at any other stage in the compounding process as a single component. Classes of compounds which would act as deblocking agents, but not normally effective as cure accelerators, allowing for selection between the two, are oxides, hydroxides, carbonates, bicarbonates, alkoxides, phenoxides, sulfanamide salts, acetyl acetonates, carbon anions derived from high acidity C—N bonds, malonic acid esters, cyclopentadienes, phenols, sulfonamides, nitrites, fluorenes, tetra-alkyl ammonium salts, and tetra-alkyl phosphonium salts.
The rubber composition need not be, but preferably is, essentially free of functionalized siloxanes, especially those of the type disclosed in Australian Patent AU-A-10082/97, which is incorporated herein by reference. Most preferably, the rubber composition is free of functionalized siloxanes.
In practice, sulfur vulcanized rubber products typically are prepared by thermomechanically mixing rubber and various ingredients in a sequentially step-wise manner followed by shaping and curing the compounded rubber to form a vulcanized product. First, for the aforesaid mixing of the rubber and various ingredients, typically exclusive of sulfur and sulfur vulcanization accelerators (collectively “curing agents”), the rubber(s) and various rubber compounding ingredients typically are blended in at least one, and often (in the case of silica filled low rolling resistance tires) two or more, preparatory thermomechanical mixing stage(s) in suitable mixers. Such preparatory mixing is referred to as non-productive mixing or non-productive mixing steps or stages. Such preparatory mixing usually is conducted at temperatures up to 140° C. to 200° C., often in the range of from 150° C. to 180° C. Subsequent to such preparatory mixing stages, in a final mixing stage, sometimes referred to as a productive mixing stage, deblocking agent (in the case of this invention), curing agents, and possibly one or more additional ingredients, are mixed with the rubber compound or composition, typically at a temperature in a range of 50° C. to 130° C., which is a lower temperature than the temperatures utilized in the preparatory mixing stages to prevent or retard premature curing of the sulfur curable rubber, which is sometimes referred to as scorching of the rubber composition. The rubber mixture, sometimes referred to as a rubber compound or composition, typically is allowed to cool, sometimes after or during a process intermediate mill mixing, between the aforesaid various mixing steps, for example, to a temperature of about 50° C. or lower. When it is desired to mold and to cure the rubber, the rubber is placed into the appropriate mold at about at least 130° C. and up to about 200° C., which will cause the vulcanization of the rubber by the mercapto groups on the mercaptosilane and any other free sulfur sources in the rubber mixture.
By thermomechanical mixing is meant that the rubber compound, or composition of rubber and rubber compounding ingredients, is mixed in a rubber mixture under high shear conditions where it autogenously heats up as a result of the mixing primarily due to shear and associated friction within the rubber mixture in the rubber mixer. Several chemical reactions may occur at various steps in the mixing and curing processes.
The first reaction is a relatively fast reaction and is considered herein to take place between the filler and the SiX 3 group of the blocked mercaptosilane. Such reaction may occur at a relatively low temperature, such as, for example, at about 120° C. The second and third reactions are considered herein to be the deblocking of the mercaptosilane and the reaction which takes place between the sulfuric part of the organosilane (after deblocking), and the sulfur vulcanizable rubber at a higher temperature; for example, above about 140° C.
Another sulfur source may be used; for example, in the form of elemental sulfur as S 8 . A sulfur donor is considered herein as a sulfur-containing compound that makes sulfur available for vulcanization at a temperature of 140° C. to 190° C. Such sulfur donors may be, but are not limited to, for example, polysulfide vulcanization accelerators and organosilane polysulfides with at least two connecting sulfur atoms in its polysulfide bridge. The amount of free sulfur source addition to the mixture can be controlled or manipulated as a matter of choice relatively independent of the addition of the aforesaid blocked mercaptosilane. Thus, for example, the independent addition of a sulfur source may be manipulated by the amount of addition thereof and by the sequence of addition relative to the addition of other ingredients to the rubber mixture.
Addition of an alkyl silane to the coupling agent system (blocked mercaptosilane condensate plus additional free sulfur source and/or vulcanization accelerator) typically in a mole ratio of alkyl silane to blocked mercaptosilane condenstate in a range of 1/50 to 1/2 promotes an even better control of rubber composition processing and aging.
A rubber composition is prepared by a process that comprises the sequential steps of:
(A) thermomechanically mixing, in at least one preparatory mixing step, to a temperature of 140° C. to 200° C., alternatively to 140° C. to 190° C., for a total mixing time of 2 to 20, alternatively 4 to 15, minutes for such mixing step(s)
(i) 100 parts by weight of at least one sulfur vulcanizable rubber selected from conjugated diene homopolymers and copolymers, and copolymers of at least one conjugated diene and aromatic vinyl compound,
(ii) 5 to 100, preferably 25 to 80, phr (parts per hundred rubber) of particulate filler, wherein preferably the filler contains 1 to 85 weight percent carbon black, and
(iii) 0.05 to 20 parts by weight filler of at least one blocked mercaptosilane condensate;
(B) subsequently blending therewith, in a final thermomechanical mixing step at a temperature to 50° C. to 130° C. for a time sufficient to blend the rubber, preferably between 1 and 30 minutes, more preferably 1 to 3 minutes, at least one deblocking agent at about 0.05 to 20 parts by weight of the filler and a curing agent at 0 to 5 phr; and, optionally, (C) curing said mixture at a temperature of 130 to 200° C. for about 5 to 60 minutes.
The process may also comprise the additional steps of preparing an assembly of a tire or sulfur vulcanizable rubber with a tread comprised of the rubber composition prepared according to this invention and vulcanizing the assembly at a temperature in a range of 130° C. to 200° C.
Suitable organic polymers and fillers are well known in the art and are described in numerous texts, of which two examples include The Vanderbilt Rubber Handbook ; R. F. Ohm, ed.; R. T. Vanderbilt Company, Inc., Norwalk, Conn.; 1990 and Manual For The Rubber Industry ; T. Kempermann, S. Koch, J. Sumner, eds.; Bayer A. G., Leverkusen, Germany; 1993. Representative examples of suitable polymers include solution styrene-butadiene rubber (sSBR), styrene-butadiene rubber (SBR), natural rubber (NR), polybutadiene (BR), ethylene-propylene co- and ter-polymers (EP, EPDM), and acrylonitrile-butadiene rubber (NBR).
The rubber composition is comprised of at least one diene-based elastomer, or rubber. Suitable conjugated dienes are isoprene and 1,3-butadiene and suitable vinyl aromatic compounds are styrene and alpha methyl styrene. Thus, the rubber is a sulfur curable rubber.
Such diene-based elastomer, or rubber, may be selected, for example, from at least one of cis-1,4-polyisoprene rubber (natural and/or synthetic), and preferably natural rubber), emulsion polymerization prepared styrene/butadiene copolymer rubber, organic solution polymerization prepared styrene/butadiene rubber, 3,4-polyisoprene rubber, isoprene/butadiene rubber, styrene/isoprene/butadiene terpolymer rubber, cis-1,4-polybutadiene, medium vinyl polybutadiene rubber (35-50 percent vinyl), high vinyl polybutadiene rubber (50-75 percent vinyl), styrene/isoprene copolymers, emulsion polymerization prepared styrene/butadiene/acrylonitrile terpolymer rubber, and butadiene/acrylonitrile copolymer rubber. An emulsion polymerization derived styrene/butadiene (eSBR) might be used having a relatively conventional styrene content of 20 to 28 percent bound styrene or, for some applications, an eSBR having a medium to relatively high bound styrene content, namely, a bound styrene content of 30 to 45 percent. Emulsion polymerization prepared styrene/butadiene/acrylonitrile terpolymer rubbers containing 2 to 40 weight percent bound acrylonitrile in the terpolymer are also contemplated as diene-based rubbers for use in this invention.
The solution polymerization prepared SBR (sSBR) typically has a bound styrene content in a range of 5 to 50, preferably 9 to 36, percent. Polybutadiene elastomer may he conveniently characterized, for example, by having at least a 90 weight percent cis-1,4-content.
Representative examples of suitable filler materials include metal oxides, such as silica (pyrogenic and precipitated), titanium dioxide, aluminosilicate and alumina, siliceous materials including clays and talc, and carbon black. Particulate, precipitated silica is also sometimes used for such purpose, particularly when the silica is used in connection with a silane. In some cases, a combination of silica and carbon black is utilized for reinforcing fillers for various rubber products, including treads for tires. Alumina can be used either alone or in combination with silica. The term “alumina” can be described herein as aluminum oxide, or Al 2 O 3 . The fillers may be hydrated or in anhydrous form. Use of alumina in rubber compositions can be shown, for example, in U.S. Pat. No. 5,116,886 and EP 631 982.
The blocked mercaptosilane may be premixed, or pre-reacted, with the filler particles or added to the rubber mix during the rubber and filler processing, or mixing stage. If the silane and filler are added separately to the rubber mix during the rubber and filler mixing, or processing stage, it is considered that the blocked mercaptosilane then combines in situ with the filler.
The vulcanized rubber composition should contain a sufficient amount of filler to contribute a reasonably high modulus and high resistance to tear. The combined weight of the filler may be as low as about 5 to 100 phr, but is more preferably from 25 to 85 phr.
Precipitated silicas are preferred as the filler. The silica may be characterized by having a BET surface area, as measured using nitrogen gas, preferably in the range of 40 to 600, and more usually in a range of 50 to 300 m 2 /g. The silica typically may also be characterized by having a dibutylphthalate (DBP) absorption value in a range of 100 to 350, and more usually 150 to 300. Further, the silica, as well as the aforesaid alumina and aluminosilicate, may be expected to have a CTAB surface area in a range of 100 to 220. The CTAB surface area is the external surface area as evaluated by cetyl trimethylammonium bromide with a pH of 9. The method is described in ASTM D 3849. Mercury porosity surface area is the specific surface area determined by mercury porosimetry. For such technique, mercury is penetrated into the pores of the sample after a thermal treatment to remove volatiles. Set-up conditions may be suitably described as using a 100 mg sample; removing volatiles during 2 hours at 105° C. and ambient atmospheric pressure; ambient to 2000 bars pressure measuring range. Such evaluation may be performed according to the method described in Winslow, Shapiro in ASTM bulletin, p.39 (1959) or according to DIN 66133. For such an evaluation, a CARLO-ERBA Porosimeter 2000 might be used. The average mercury porosity specific surface area for the silica should be in a range of 100 to 300 m 2 /g.
A suitable pore size distribution for the silica, alumina, and aluminosilicate according to such mercury porosity evaluation is considered herein to be: five percent or less of its pores have a diameter of less than about 10 nm; 60 to 90 percent of its pores have a diameter of 10 to 100 nm; 10 to 30 percent of its pores have a diameter at 100 to 1,000 nm; and 5 to 20 percent of its pores have a diameter of greater than about 1,000 nm.
The silica might be expected to have an average ultimate particle size, for example, in the range of 0.01 to 0.05 μm as determined by the electron microscope, although the silica particles may be even smaller, or possibly larger, in size. Various commercially available silicas may be considered for use in this invention, such as, from PPG Industries under the HI-SIL trademark with designations HI-SIL 210, 243, etc.; silicas available from Rhone-Poulenc, with, for example, designation of ZEOSIL 1165MP; silicas available from Degussa with, for example, designations VN2 and VN3, etc., and silicas commercially available from Huber having, for example, a designation of HUBERSIL 8745.
Where it is desired for the rubber composition, which contains both a siliceous filler, such as silica, alumina, and/or aluminosilicates and also carbon black reinforcing pigments, to be primarily reinforced with silica as the reinforcing pigment, it is often preferable that the weight ratio of such siliceous fillers to carbon black be at least 3/1 and preferably at least 10/1 and, thus, in a range of 3/1 to 30/1. The filler may be comprised of 15 to 95 weight percent precipitated silica, alumina, and/or aluminosilicate and, correspondingly, 85 to 5 weight percent carbon black, wherein the carbon black has a CTAB value in a range of 80 to 150. Alternatively, the filler can be comprised of 60 to 95 weight percent of said silica, alumina, and/or aluminosilicate and, correspondingly, 40 to 5 weight percent carbon black. The siliceous filler and carbon black may be pre-blended or blended together in the manufacture of the vulcanized rubber.
The rubber composition may be compounded by methods known in the rubber compounding art, such as mixing the various sulfur-vulcanizable constituent rubbers with various commonly used additive materials such as, for example, curing aids, such as sulfur, activators, retarders, and accelerators, processing additives, such as oils, resins including tackifying resins, silicas, plasticizers, fillers, pigments, fatty acid, zinc oxide, waxes, antioxidants and antiozonants, peptizing agents, and reinforcing materials, such as, for example, carbon black. Depending on the intended use of the sulfur vulcanizable and sulfur vulcanized material (rubbers), the additives mentioned above are selected and commonly used in conventional amounts.
The vulcanization may be conducted in the presence of an additional sulfur vulcanizing agent. Examples of suitable sulfur vulcanizing agents include, for example, elemental sulfur (free sulfur) or sulfur donating vulcanizing agents, for example, an amino disulfide, polymeric polysulfide, or sulfur olefin adducts which are conventionally added in the final, productive, rubber composition mixing step. The sulfur vulcanizing agents (which are common in the art) are used, or added in the productive mixing stage, in an amount ranging from 0.4 to 3 phr, or even, in some circumstances, up to about 8 phr, with a range of from 1.5 to 2.5 phr, sometimes from 2 to 2.5 phr, being preferred. Vulcanization accelerators may be used herein. It is appreciated that they may be of the type, such as, for example, benzothiazole, alkyl thiuram disulfide, guanidine derivatives, and thiocarbamates. Vulcanization accelerators may be primary or secondary accelerators and individual accelerators may function as either primary or secondary accelerators. Representative accelerators include, but not limited to, mercapto benzothiazole, tetramethyl thiuram disulfide, benzothiazole disulfide, diphenylguanidine, zinc dithiocarbamate, alkylphenoldisulfide, zinc butyl xanthate, N-dicyclohexyl-2-benzothiazolesulfenamide, N-cyclohexyl-2-benzothiazolesulfenamide, N-oxydiethylenebenzothiazole-2-sulfenamide, N,N-diphenylthiourea, dithiocarbamylsulfenamide, N,N-diisopropylbenzothiozole-2-sulfenamide, zinc-2-mercaptotoluimidazole, dithiobis(N-methyl piperazine), dithiobis(N-beta-hydroxy ethyl piperazine), and dithiobis(dibenzyl amine). Other additional sulfur donors, may be, for example, thiuram and morpholine derivatives. Such donors include, but not limited to, dimorpholine disulfide, dimorpholine tetrasulfide, tetramethyl thiuram tetrasulfide, benzothiazyl-2,N-dithiomorpholide, thioplasts, dipentamethylenethiuram hexasulfide, and disulfidecaprolactam.
Accelerators are used to control the time and/or temperature required for vulcanization and to improve the properties of the vulcanizate. In one embodiment, a single accelerator system may be used, i.e., a primary accelerator. Conventionally and preferably, a primary accelerator is used in a total amount ranging from 0.5 to 4, preferably 0.8 to 1.5, phr. Combinations of a primary and a secondary accelerator might be used with the secondary accelerator being used in a smaller amount (of 0.05 to 3 phr) in order to activate and to improve the properties of the vulcanizate. Delayed action accelerators may be used. Vulcanization retarders might also be used. Suitable types of accelerators are amines, disulfides, guanidines, thioureas, thiazoles, thiurams, sulfenamides, dithiocarbamates, and xanthates, but the type may be influenced if the accelerant is also a deblocker. Examples of primary accelerators used in the art include N-cyclohexyl-2-benzothiazyl sulfenamide (CBS); N-t-butyl-2-benzothiazyl sulfenamide (TBBS); benzothiazyl-2-sulphene morpholide (MBS); N-dicyclohexyl-2-benzothiazyl sulfenamide (DCBS); tetramethylthiuram monosulfide (TMTM); tetramethylthiuram disulfide (TMTD); tetramethylthiuram hexasulfide; N,N-diphenylurea; and morpholinethiobenzothiazole. If a second accelerator is used, the secondary accelerator is preferably a guanidine, dithiocarbamate, or thiuram compound. Examples of secondary accelerators commonly used in the art include diphenylguanidine (DPG); tetramethylthiuram hexasulfide; mercaptobenzothiazole (MBT); mercaptobenzothiazole disulfide (MBTS); the zinc salt of mercaptobenzothiazole (ZMBT); zinc dibutyldithiocarbamate; zinc diethyldithiocarbamate; zinc dimethyldithiocarbamate; zinc dibenzyldithiocarbamate; zinc ethylphenyldithiocarbamate; nickel dibutyldithiocarbamate; copper dimethyldithiocarbamate; piperidinium pentamethylene dithiocarbamate; thiocarbanilide; 1,3-diethylthiourea-1,3-dibutylthiourea; di(pentamethylene)thiuram hexasulfide; and morpholinethiobenzothiazole. Numerous specific examples of guanidines, amines, and imines well known in the art, which are useful as components in curatives for rubber, are cited in Rubber Chemicals ; J. Van Alphen; Plastics and Rubber Research Institute TNO, Delft, Holland; 1973.
In elastomer formulations of the present invention, it is important to consider an additional factor in the choice of the accelerator system. This factor is related to the deblocking action of the accelerator on the blocked mercaptosilane condensate. Deblocking of the blocked mercaptosilane condensate occurs by the catalytic or chemical action of a component added to the elastomer at a point where deblocking is desired. Amines or related basic substances are particularly suitable in this regard. Most of the aforementioned accelerators are amine based, but their basicity may be reduced because the nitrogen atom is bound to a sulfur atom, carbonyl, or thiocarbonyl. This influences the type of accelerator package ideally suited for elastomer compositions of the present invention. Thus, a preferred method of operation would be to use such amines as both deblocking agent and accelerator.
Among the accelerators of demonstrated suitability for use with blocked mercaptosilane condensates are diphenylguanidine (DPG) and tetramethylthiuram monosulfide (TMTM). The TMTM is preferred. It is believed that the family of such compounds, i.e., R 2 NC(═S)—S n —C(═S)NR 2 wherein n=1 to 4, R is an akyl group of 1 to 4 carbon atoms, would be preferred.
Free amines, or closely related chemical compounds, such as imines, anilines, and nitrogen-containing heterocycles are expected to deblock and thereby activate the blocked mercaptosilanes much more readily, rapidly, and/or completely than many of the aforementioned accelerators on the basis of their stronger basicity. Suitable amine accelerators would be secondary or tertiary amines containing substantial carbon content so that they contain sufficient hydrophobicity in their structure to offset the hydrophilicity of the basic amine group, so that dispersion into the rubber matrix is promoted. All such compounds should have boiling points of at least 140° C. and preferably greater than 200° C. This includes secondary or tertiary amines with enough carbon content to be miscible in the rubber mixture, generally about a molar ratio of C:N of at least 6:1. Alternatively, the amine may be a heterocyclic amine of the following classes: quinoline, imidazoline, imidazolidone, hydantoin, hydralazine, pyrazole, pyrazine, purine, pyrimidine, pyrrole, indole, oxazole, thiazole, benzimidazole, benzoxazole, benzothiazole, triazole, benzotriazole, tetrazole, aniline, phenylene diamine, and imine. Factors in considering the accelerators of the free amine type would, of course, be factors such as toxicity, physical state (i.e. liquid or solid), volatility, its ability to disperse into the formulation, and the like.
Most suitably, one can use mixtures of the vulcanization accelerators, which are used to deblock the silane with the aforementioned deblocking agents to control the rate and degree of rubber cure as to to deblocking and crosslinking of the silane. Each rubber mixture will have its own optimal blend which may be determined by simple experimentation.
Typical amounts of tackifier resins, if used, comprise 0.5 to 10 phr, usually 1 to 5 phr. Typical amounts of processing aids comprise 1 to 50 phr. Such processing aids can include, for example, aromatic, naphthenic, and/or paraffinic processing oils. Typical amounts of antioxidants comprise 1 to 5 phr. Representative antioxidants may be, for example, diphenyl-p-phenylenediamine and others, such as, for example, those disclosed in the Vanderbilt Rubber Handbook (1978), pages 344-346. Typical amounts of antiozonants, comprise 1 to 5 phr. Typical amounts of fatty acids, if used, which can include stearic acid, comprise 0.5 to 3 phr. Typical amounts of zinc oxide comprise 2 to 5 phr. Typical amounts of waxes comprise 1 to 5 phr. Often microcrystalline waxes are used. Typical amounts of peptizers comprise 0.1 to 1 phr. Typical peptizers may be, for example, pentachlorothiophenol and dibenzamidodiphenyl disulfide.
The rubber composition of this invention can be used for various purposes. For example, it can be used for various tire compounds. Such tires can be built, shaped, molded, and cured by various methods which are known and will be readily apparent to those having skill in such art.
All references cited herein are incorporated by reference to the extent they are relevant to the present invention.
Various features and aspects of the present invention are illustrated further in the examples that follow. While these examples are presented to show one skilled in the art how to operate within the scope of the invention, they are not intended in any way to serve as a limitation upon the scope of the invention.
EXAMPLES
Example 1
Homogeneous Preparation of a
Condensate of 3-acetylthio-1-propyltriethoxysilane
A crude starting material of 3-acetylthio-1-propyltriethoxysilane was first purified by flash vacuum distillation from sodium ethoxide. The distillate was redistilled. An initial forecut of volatiles was discarded and the bulk of the distillate was retained as a clear and colorless liquid, which was used as the starting material for the preparation of the condensate. To a homogeneous mixture of 3-acetylthio-1-propyltriethoxysilane (74.35 grams, 0.2525 mole) and anhydrous ethanol (70 grams) was added a modest quantity of water (2.27 grams, 0.126 mole), with stirring. The mixture was allowed to stand at ambient temperature for six weeks. After this time, volatiles were removed by rotary evaporation.
Example 2
Heterogeneous Preparation of a
Condensate of 3-acetylthio-1-propyltriethoxysilane
A crude starting material of 3-acetylthio-1-propyltriethoxysilane was first purified by flash vacuum distillation from sodium ethoxide. The distillate was redistilled. An initial forecut of volatiles was discarded and the bulk of the distillate was retained as a clear and colorless liquid, which was used as the starting material for the preparation of the condensate. A two-phase mixture of 3-acetylthio-1-propyltriethoxysilane (68.3 grams, 0.232 mole) and water (49 grams, 2.7 moles) was stirred for six weeks at ambient temperature. After this time, the liquid layers were separated in a separatory funnel. Volatiles were removed by rotary evaporation from the organic phase.
Example 3
Homogeneous Preparation of a Condensate of [8-octanoylthio-1-propyltriethoxysilane]3-triethoxysilyl-1-propyl thiooctoate
A quantity of [8-octanoylthio-1-propyltriethoxysilane]3-triethoxysilyl-1-propyl thiooctoate (240 grams, 0.66 mole) was added to a homogeneous mixture of anhydrous ethanol (54 grams) and water (5.93 grams, 0.329 mole) with stirring. The mixture was allowed to stand at ambient temperature for six weeks. After this time, volatiles were removed by rotary evaporation. The product was further purified by flash vacuum distilling out a forecut and retaining the nonvolatile portion of the sample. The forecut contained most of the ethyl octoate, 3-mercapto-1-propyltriethoxysilane, and 3-chloro-1-propyltriethoxysilane impurities present in the sample, as established by comparative GC (gas chromatography) with pure samples of the respective contaminants. GC analytical results (area %): Si—O-—Si siloxane “dimer” of [8-octanoylthio-1-propyltriethoxysilane]3-triethoxysilyl-1-propyl thiooctoate 46.4%; [8-octanoylthio-1-propyltriethoxysilane]3-triethoxysilyl-1-propyl thiooctoate 33.0%; 1-diethoxy-1-sila-2-thiacyclopentane 0.2%; bis-3-triethoxysilyl-1-propyl disulfide 4.4%; bis-3-triethoxysilyl-1-propyl trithiocarbonate 1.0%. Higher molecular weight components of Si—O—Si siloxane “trimers”, “tetramers”, etc. of [8-octanoylthio-1-propyltriethoxysilane]3-triethoxysilyl-1-propyl thiooctoate are expected in these compositions, but would not have been detected by the GC spectra taken.
Example 4
Heterogeneous Preparation of a Condensate of [8-octanoylthio-1-propyltriethoxysilane]3-triethoxysilyl-1-propyl thiooctoate
A two-phase mixture of [8-octanoylthio-1-propyltriethoxysilane]3-triethoxysilyl-1-propyl thiooctoate (124.3 grams, 0.3409 mole) and water (175 grams, 9.71 mole) was stirred at ambient temperature for six weeks. After this time, the liquid layers were separated in a separatory funnel. Volatiles were removed by rotary evaporation from the organic phase. The product was further purified by flash vacuum distilling out a forecut and retaining the nonvolatile portion of the sample. The forecut contained most of the ethyl octoate, 3-mercapto-1-propyltriethoxysilane, and 3-chloro-1-propyltriethoxysilane impurities present in the sample, as established by comparative GC with pure samples of the respective contaminants. GC analytical results (area %): Si—O—Si siloxane “dimer” of [8-octanoylthio-1-propyltriethoxysilane]3-triethoxysilyl-1-propyl thiooctoate 39.0%; [8-octanoylthio-1-propyltriethoxysilane]3-triethoxysilyl-1-propyl thiooctoate 37.1%; 1-diethoxy-1-sila-2-thiacyclopentane 0.4%; 3-mercapto-1-propyltriethoxysilane 0.2%; 3-ethylthio-1-propyltriethoxysilane 0.3%; bis-3-triethoxysilyl-1-propyl disulfide 5.3%; bis-3-triethoxysilyl-1-propyl trithiocarbonate 1.8%. Higher molecular weight components of Si—O—Si siloxane “trimers”, “tetramers”, etc. of [8-octanoylthio-1-propyltriethoxysilane]3-triethoxysilyl-1-propyl thiooctoate are expected in these compositions, but would not have been detected by the GC spectra taken.
Example 5
Heterogeneous, Acid-Catalyzed Preparation of a Condensate of [8-octanoylthio-1-propyltriethoxysilane]3-triethoxysilyl-1-propyl thiooctoate
A two-phase mixture of [8-octanoylthio-1-propyltriethoxysilane]3-triethoxysilyl-1-propyl thiooctoate (125.1 grams, 0.3431 mole), water (83.4 grams, 4.63 moles), and glacial acetic acid (12.5 grams, 0.208 mole) was stirred for six weeks at ambient temperature. After this time, the liquid layers were separated in a separatory funnel. Volatiles were removed by rotary evaporation from the organic phase. The product was further purified by flash vacuum distilling out a forecut and retaining the nonvolatile portion of the sample. The forecut contained most of the ethyl octoate, 3-mercapto-1-propyltriethoxysilane, and 3-chloro-1-propyltriethoxysilane impurities present in the sample, as established by comparative GC with pure samples of the respective contaminants. GC analytical results (area %): Si—O—Si siloxane “dimer” of [8-octanoylthio-1-propyltriethoxysilane]3-triethoxysilyl-1-propyl thiooctoate 30.2%; [8-octanoylthio-1-propyltriethoxysilane]3-triethoxysilyl-1-propyl thiooctoate 50.5%; 3-mercapto-1-propyltriethoxysilane 0.2%; bis-3-triethoxysilyl-1-propyl disulfide 5.1%; bis-3-triethoxysilyl-1-propyl trithiocarbonate 1.8%. Higher molecular weight components of Si—O—Si siloxane “trimers”, “tetramers”, etc. of [8-octanoylthio-1-propyltriethoxysilane]3-triethoxysilyl-1-propyl thiooctoate are expected in these compositions, but would not have been detected by the GC spectra taken.
Example 6
Base-Catalyzed Preparation of a Condensate of [8-octanoylthio-1-propyltriethoxysilane]3-triethoxysilyl-1-propyl thiooctoate
To the homogeneous mixture of [8-octanoylthio-1-propyltriethoxysilane]3-triethoxysilyl-1-propyl thiooctoate (72.12 grams, 0.1978 mole) and ethanol (72.3 grams) was added a modest quantity of water. The resulting mixture was stirred to a homogeneous solution, to which was subsequently added a modest quantity of water (19.6 grams, 1.09 moles). This mixture was then stirred, resulting in another homogeneous mixture. To this resulting mixture was added a small quantity of sodium ethoxide (0.086 gram, 0.0013 mole) as a 21 weight % solution (0.41 gram) in ethanol. This mixture was then stirred at ambient temperature, giving a homogeneous solution. A slight phase separation was evident in this mixture after stirring for one day. Stirring at ambient temperature was then continued for another six weeks. After this time, the liquid layers were separated in a separatory funnel. The organic was by far the predominant phase. Volatiles were removed from the organic phase by rotary evaporation. The product was further purified by flash vacuum distilling out a forecut and retaining the nonvolatile portion of the sample. The forecut contained most of the ethyl octoate, 3-mercapto-1-propyltriethoxysilane, and 3-chloro-1-propyltriethoxysilane impurities present in the sample, as established by comparative GC with pure samples of the respective contaminants. GC analytical results (area %): Si—O—Si siloxane “dimer” of [8-octanoylthio-1-propyltriethoxysilane]3-triethoxysilyl-1-propyl thiooctoate 23.6%; [8-octanoylthio-1-propyltriethoxysilane]3-triethoxysilyl-1-propyl thiooctoate 58.7%; 1-diethoxy-1-sila-2-thiacyclopentane 0.1%; 3-mercapto-1-propyltriethoxysilane 0.5%; bis-3-triethoxysilyl-1-propyl disulfide 5.1%; bis-3-triethoxysilyl-1-propyl trithiocarbonate 1.2%. Higher molecular weight components of Si—O—Si siloxane “trimers”, “tetramers”, etc. of [8-octanoylthio-1-propyltriethoxysilane]3-triethoxysilyl-1-propyl thiooctoate are expected in these compositions, but would not have been detected by the GC spectra taken.
Example 7
Formic Acid Catalyzed Preparation of a Condensate of [8-octanoylthio-1-propyltriethoxysilane]3-triethoxysilyl-1-propyl thiooctoate
Into a one liter round bottomed flask equipped with a distillation apparatus, addition funnel, thermometer, heating mantle, and magnetic stirrer was added 200 grams (0.55 mole) of [3-octanoylthio-1-propyltriethoxysilane]3-triethoxysilyl-1-propyl thiooctoate and 1.0 gram of Purolite CT-275 dry, acidic ion exchange resin. From the addition funnel was added 12.6 grams (0.27 mole) of 96% formic acid while heating the flask contents to 80° C. with stirring. Distillation at 80° C. and 5 mm mercury vacuum, yielded 28.2 grams of low boiling components (mainly, ethanol and ethyl formate). The flask contents were filtered to yield 164.2 grams of 10 csk viscosity. Analysis by 29 Si NMR indicated 2.26 ethoxy groups per Si and 13 C NMR showed 2.13 ethoxy groups per Si and no loss of octanoyl groups on sulfur.
Example 8
Formic Acid Catalyzed Preparation of a Condensate of [8-octanoylthio-1-propyltriethoxysilane]3-triethoxysilyl-1-propyl thiooctoate and tetraethyl silicate
Using the apparatus described in Example 7, a mixture of 364.0 grams (1.0 mole) of [3-octanoylthio-1-propyltriethoxysilane]3-triethoxysilyl-1-propyl thiooctoate, 208.3 grams (1.0 mole) of tetraethyl silicate and 2.7 grams of Purolite CT-275 ion exchange resin were added to the flask. From the addition funnel 30.6 grams water (1.7 moles) was added to the flask while the contents of the flask were heated to 55° C. The temperature was maintained at 50-55° C. for three hours with stirring. The flask was cooled to room temperature, filtered and the lower boiling components were vacuum distilled (85° C., 8 mm Hg) from the flask (mainly ethanol, 127.0 grams) to yield upon isolation 423.6 grams of an amber liquid of 14 cstk viscosity. The 13 C NMR confirmed that all of the octanoyl groups remained on sulfur after this reaction.
Example 9
Formic Acid Catalyzed Preparation of a Condensate of [8-octanoylthio-1-propyltriethoxysilane]3-triethoxysilyl-1-propyl thiooctoate and octyltriethoxysilane
Using the apparatus described in Example 7, a mixture of 364.0 grams (1.0 mole) of [3-octanoylthio-1-propyltriethoxysilane]3-triethoxysilyl-1-propyl thiooctoate, 276.5 grams (1.0 mole) of octyltriethoxysilane and 2.7 grams of Purolite CT-275 ion exchange resin were added to the flask. From the addition funnel 30.6 grams water (1.7 moles) was added to the flask while the contents of the flask were heated to 50° C. The temperature was maintained at 50-55° C. for two hours with stirring. The flask was cooled to room temperature, filtered, and the lower boiling components were vacuum distilled (80° C., 2 mm Hg) from the flask (mainly ethanol, 111.5 grams) to yield upon isolation 484.6 grams of an amber liquid of 14 cstk viscosity. The 13 C NMR confirmed that the octanoyl groups remained on sulfur after this reaction.
Example 10
Formic Acid Catalyzed Preparation of a Condensate of [8-octanoylthio-1-propyltriethoxysilane]3-triethoxysilyl-1-propyl thiooctoate and phenyltriethoxysilane
Using the apparatus described in Example 7, a mixture of 364.0 grams (1.0 mole) of [3-octanoylthio-1-propyltriethoxysilane]3-triethoxysilyl-1-propyl thiooctoate, 240.4 grams (1.0 mole) of phenyltriethoxysilane and 2.7 grams of Purolite CT-275 ion exchange resin were added to the flask. From the addition funnel 30.6 grams water (1.7 moles) was added to the flask while the contents of the flask were stirred at room temperature for 1.5 days, then were heated to 50° C. for 2 hours. The flask was cooled to room temperature, filtered, and the lower boiling components were vacuum distilled (50° C., 10 mm Hg) from the flask (mainly ethanol, 125.7 grams) to yield upon isolation 469.1 grams of an amber liquid of 14 cstk viscosity. The 13 C NMR confirmed that the octanoyl groups remained on sulfur after this reaction.
Examples 11-22
In the following examples, the amounts of reactants are parts per hundred of rubber unless otherwise indicated.
The following tests were conducted with the following methods (in all examples): Mooney Viscosity @100° C. (ASTM Procedure D1646); Mooney Scorch @135° C. (ASTM Procedure D1646); Oscillating Disc Rheometer (ODR) @149° C., 1° arc, (ASTM Procedure D2084); Physical Properties, cured t90 @149° C. (ASTM Procedures D412 and D224).
Formulation: 75 Solflex 1216 sSBR, 25 Budene 1207 BR, 80 Zeosil 1165MP silica, 32.5 Sundex 3125 process oil, 2.5 Kadox 720C zinc oxide, 1.0 Industrene R stearic acid, 2.0 Santoflex 13 antiozonant, 1.5 M4067 microwax, 3.0 N330 carbon black, 1.4 Rubbermakers sulfur 104, 1.7 CBS, 2.0 DPG, and 7.2 silane.
Mixing of the formulations was carried out in a Banbury Mixer during an eight minute mixing period at 170° C. for all samples. The results of physical testing of these formulations are shown in Tables 1-(A-D). In the tables, the term “Prodex” is used, for convenience, to mean “The product of Example”. Thus, for example, “Prodex 10” should be understood to mean “The product of Example 10”. Where this terminology is not used, the products were made by a process analogous to that described in Example 8. Further, “Y-15099” is [8-octanoylthio-1-propyltriethoxysilane]3-triethoxysilyl-1-propyl thiooctoate and “TEOS” is tetraethoxy silane.
TABLE 1-A
Example No.
11
12
13
14
15
16
17
Y-15099
7.2
Prodex 10
7.2
Y-15099/TEOS/oligo-
7.2
merized
Prodex 9
7.2
Prodex 7
7.2
Hydrolysis Y-15099/
7.2
TEOS/H 2 O (1/1/1)
Hydrolysis Y-15099/
7.2
TEOS/H 2 O (1/1/1.9)
Mooney Viscosity @
100° C.
ML1 + 4
56
62
59
54
62
61
58
Mooney Scorch @
135° C.
M v
24.3
24.6
25.3
21.9
27.1
26.0
24.2
MS1+, t 3 , minutes
8.6
13.4
10.2
16.4
9.4
10.1
9.6
MS1+, t 18 , minutes
12.4
18.2
14.5
21.5
14.2
14.5
14.1
TABLE 1-B
Example No.
11
12
13
14
15
16
17
ODR @ 149° C., 1° arc, 30 minute timer
M L in.-lb.
6.9
6.8
7.1
6.0
7.6
7.0
6.6
M H , in.-lb.
25.8
29.5
26.5
27.3
26.9
27.3
26.1
t S1 , minutes
5.2
7.4
5.5
8.3
5.1
5.3
5.4
t90, minutes
12.4
15.5
15.5
17.2
16.2
15.5
14.2
Physical Properties, cured t90 @ 149° C.
Hardness, Shore A
55
62
58
58
61
60
57
Elongation, %
604
643
676
658
691
683
699
25% Modulus, psi
92
118
100
103
108
112
109
100% Modulus, psi
218
275
218
234
224
225
227
300% Modulus, psi
1,110
1,232
1,012
1,029
946
909
1,015
Tensile, psi
3,321
3,390
3,460
3,112
3,255
3,159
3,533
300%/25%
12.1
10.4
10.1
10.0
8.8
8.1
9.3
300%/100%
5.1
4.5
4.6
4.4
4.2
4.0
4.5
TABLE 1-C
Example No.
18
19
20
21
22
Prodex 3
7.2
Hydrolysis Y-15099/TEOS/H 2 O
7.2
(1/1/1.5)
Prodex 5
7.2
Prodex 6
7.2
Prodex 4
7.2
Mooney Viscosity @ 100° C.
ML1 + 4
60
58
59
60
61
Mooney Scorch @ 135° C.
M v
30.0
24.3
28.1
28.8
31.1
MS1+, t 3 , minutes
3.6
9.1
5.1
5.0
4.3
MS1+, t 18 , minutes
5.4
12.6
7.1
7.1
5.6
TABLE 1-D
Example No.
18
19
20
21
22
ODR @ 149° C., 1° arc,
30 minute timer
M L in.-lb.
7.7
6.6
7.6
7.6
8.1
M H , in.-lb.
25.6
26.5
25.2
25.1
24.9
t S1 , minutes
3.2
5.2
3.2
3.3
2.5
t90, minutes
8.4
13.1
8.4
10.3
9.2
Physical Properties,
cured t90 @ 149° C.
Hardness, Shore A
55
57
54
55
55
Elongation, %
564
660
549
584
518
25% Modulus, psi
102
116
107
110
108
100% Modulus, psi
237
239
232
251
247
300% Modulus, psi
1,183
1,070
1,170
1,190
1,274
Tensile, psi
3,380
3,433
3,229
3,400
3,154
300%/25%
11.6
9.2
10.9
10.8
11.8
300%/100%
5.0
4.5
5.0
4.7
5.2
In view of the many changes and modifications that can be made without departing from principles underlying the invention, reference should be made to the appended claims for an understanding of the scope of the protection to be afforded the invention. | Rubber composition intended for the manufacture of tire casings which have improved hysteretic properties and scorch safety, based on at least one elastomer and silica by way of reinforcing filler enclosing a reinforcing additive consisting of the mixture and/or the product of in situ reaction of at least one functionalized polyorganosiloxane compound containing, per molecule, at least one functional siloxy unit capable of bonding chemically and/or physically to the surface hydroxyl sites of the silica particles and at least one functionalized organosilane compound containing, per molecule, at least one functional group capable of bonding chemically and/or physically to the polyorganosiloxane and/or the hydroxyl sites of the silica particles and at least one other functional group capable of bonding chemically and/or physically to the polymer chains. | 2 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] Not Applicable.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0002] Not Applicable.
REFERENCE TO SEQUENCE LISTING, A TABLE, OR A COMPUTER PROGRAM LISTING COMPACT DISC APPENDIX
[0003] Not Applicable.
BACKGROUND OF THE INVENTION
[0004] Field of the Invention
[0005] The present invention relates to information security in general, more particularly to cryptography and the use of asymmetric schemes to enforce secrecy over a non secure channel without support of prior secrets. The nature of the invention in its optimal setup is pre-message in itself, only establishing a secret information pool, although there are applications which introduces integrated messaging routines into the scheme. The use of such a information pool as a key for cipher creation helps in preventing unauthorized use or access of information during its transfer and storage, thereby maintaining the secrecy and integrity of information exchanged over a (digital) network.
[0006] Description of the Related Art
[0007] Cryptography is the science of protecting information from eavesdropping and interception, encoding messages or information in such a way that only authorized parties can read it. Encryption facilitates the secure management of data by scrambling the content. The two principle objectives are secrecy (to prevent unauthorized disclosure) and integrity (to prevent unauthorized modification). A number of techniques are known to provide this protection, and the nature of the area also makes it preferable with multiple alternatively methods of handling. Encryption does not of itself prevent interception, but hides the content of the message from the interceptor. In an encryption scheme, the message intended for communication is encrypted by use of an encryption algorithm, generating cipher text that can only be read if decrypted. To adapt to the nature of the message, developing necessary substance from a key, an encryption scheme usually uses a pseudo-random algorithm. It is in principle possible to decrypt the message without possessing the key, but, for a well-designed encryption scheme, large computational resources and skill will then be required. An authorized recipient can easily decrypt the message with the key provided by the originator to recipients. Symmetric schemes is the old way to approach the need for protection of information and these schemes can be constructed in a virtually endless number of ways, but their limiting feature is the need for the sender and the receiver to share a common key. The problem is to distribute that key to the sender and the receiver in a way that prevents eavesdropping. Asymmetric keys are the common answer to that problem. Asymmetric encryption is based on a key pair, one secret key for decryption and one open key for encryption. The open key will be of no use for decryption which is what's bypassing the limits of symmetric encryption.
[0008] The following scenario lies implicit. An primary actor creates a pair of keys, whereof one is private and the other one is public. A secondary actor who wants to convey a confidential message to the primary actor uses the public key to encrypt the message, which is subsequently sent. The primary actor now uses his private key to decrypt the message. In this scenario, only the primary actor has any part of the creation of the keys. Already in the third phase of interaction, a natural language message can be conveyed. Depending on the type of communication, asymmetric schemes of this type can be used to establish a common session key between the primary and secondary actor, which is then replacing the natural language message as the first message. In that case the scenario will look like this: The primary actor sends a copy of his asymmetric public key. The secondary actor creates a symmetric session key and encrypts it with the primary actor's asymmetric public key. He then sends the symmetric session key to the primary actor. The primary actor decrypts the encrypted session key using his asymmetric private key to get the symmetric session key. The primary and secondary actor now are able to encrypt and decrypt all transmitted messages with the symmetric session key. The most important method to achieve this scheme is the RSA method. The asymmetric to symmetric approach is commonly used for interchanging data sessions between two parties, for instance over Internet. The reason for the switch to a symmetric solution from an asymmetric one is that these two solutions accomplish two different things. The initial, asymmetric scheme allows a buildup of a secret information pool, common for the primary and the secondary actor, over a non secure medium, which pool is used as a session key. No previous secrets between the parties are needed. The symmetric solution achieves a higher level of security for the subsequent data exchange per data. The computational costs are also significantly lower for a symmetric solution. A second major asymmetric approach to accomplish the buildup of a secret information pool between a sender and a receiver, or a group of inter messaging parties, is the Diffie Hellman algorithm. The Diffie Hellman algorithm is a key agreement algorithm and most key agreement algorithms are also related to this specific algorithm in one way or another. In the methodology, the Diffie Hellman algorithm is symmetric, in that the steps of action on each side is equal, but the content sent is asymmetric. The factual method for two participants looks like this. First actor A and actor B openly agrees on the use of two large prime numbers, pf and pm. These can in practice be attached to the first message. Both parties now choose one secret, large prime number on each side, pA and pB. A now computes pf pA mod pm and send the result to B, while B computes pf pB mod pm and send the result to A. Then A calculates (pf pB mod pm) pA while B calculates (pf pA mod pm) pB , which operations both will give the same result, namely pf pApB . This value will then be used as a shared, secret information pool (key) for further symmetric encryption. The underlying, mathematical problem for the Diffie Hellman algorithm and RSA is the same, namely prime factorization. The fastest way to solve the problem of prime factorization is often said to be the General number field sieve. Therefore, the security aspect, the data to security ratio is similar for the two methods. Both methods are also computationally expensive. There are also asymmetric key systems in use, which do not rely on prime number. Examples hereof is NTRUEncrypt, Elliptic curve cryptography, Hidden Fields Equations and McEliece cryptosystem. Their common feature is that they are built around mathematical problems which are of a high level of complexity.
[0009] A solution based on asymmetric keys is generally said to be 200-1000 times as costly computationally as a symmetric solution. Regarding its need for more information resources to accomplish a specified level of security, the cost of for instance a message exchange keyed with RSA, which is widely used, will approach 25 times the cost of an symmetrically, 128 bits keyed exchange with the same real information content. For higher security levels this ratio will rapidly go even higher. It would then be a significant improvement with a scheme that allows formation of keys of symmetric session type or consecutive nature, over an insecure medium, without prior secrets, and without the high costs associated with previously known asymmetric key techniques.
BRIEF SUMMARY OF THE INVENTION
[0010] The present invention is an approach to be able to solve the issue of having to establishing a first or successive shared secret between a sender and a receiver over an non secure channel, supposedly available for everyone, in the fastest and most secure manner possible.
DESCRIPTION OF THE DRAWINGS
[0011] For a more complete understanding of the present invention, reference is now made to the following descriptions:
[0012] FIG. 1 The environmental settings for the description.
[0013] FIG. 2 The three principal phases which are parts of the method.
[0014] FIG. 3 Access the different parts of the matrix.
[0015] FIG. 4 The continuation of access the different parts of the matrix.
[0016] FIG. 5 Provides a detailed, exemplified view of the primary phase, with the preparations of the initial sender.
[0017] FIG. 6 Shows the same example operated by the initial receiver in the secondary phase from before.
[0018] FIG. 7 A view over the retrieval of the solution point i.e the tertiary phase from before.
[0019] FIG. 8 Shows the view of a hacker.
DETAILED DESCRIPTION OF THE INVENTION
[0020] The following detailed description is of the best currently contemplated modes of carrying out exemplary embodiments of the invention. The description is not to be taken in a limiting sense, but is made merely for the purpose of illustrating the general principles of the invention.
[0021] Referring to FIG. 1 in which is seen the environmental settings for the description. Here is illustrated ( 101 ) the participation of an initial sender machine node, and likewise ( 102 ) the participation of an initial receiver machine node, engaging in (A) communication by means of a data transmission system. This system is unsafe, meaning that any exchange of information will always have to take in account the possibility of ( 103 ) any number of unauthorized parties, i.e hackers trying to intercept the communication in various ways. The primary agreements for communication are open by integration in an ( 104 ) public application which is expected to be available for the initial sender and the initial receiver as a ruleset for understanding, but by consequence of its public nature also for any hacker.
[0022] The procedure of the method described proceeds over three phases, schematized in FIG. 2 . There are three principal phases shown which are parts of the method, presuming necessary connections have been established. The primary phase ( 201 ) starts with the initial sender constructing a table of equations. The preferred implementation hereof will later be shown as binary tables, as this is likely to render the highest information density possible. Also, a design which implies all equations (and parameter set) to be of equal length will allow the highest level of obfuscation and security later shown, and will therefore be anticipated in this description. Each equation here described consists of one variable set, i.e a series of binary variables, added together without carry, a boolean operation known as XOR, and its solution, a single binary. So each variable is a binary and it will also be multiplied with another binary, a parameter, before it and all other variables of the equations are added together by XOR. This means that some variables are irrelevant for the equations, namely those which are multiplied with 0 beforehand. Only variables multiplied with 1 will be relevant and they will sum together to form the solution. The parameter set and the variable set will therefore be of equal length. The table constructed by the initial sender will list an entire series of equations, each consisting of variables, which, position by position, are multiplied with one and the same parameter set, after XOR resulting in one single bit solution for each equation.
[0023] The entire table with variables and solutions, but without any parameters, will at this point be sent to the initial receiver, whose actions form the secondary phase ( 202 ) in the figure. The initial receiver will continue the process by active participation in the creation of a symmetric key, which will then be used. This is the most information efficient scheme. His objective is to create a new table of obfuscated equations with solutions, at a glance looking like some variant of the table already sent to him. Each obfuscated equation must be merged together from a randomly chosen sample of the original equations. The choice of original equations participating in any sample founding one obfuscated, new equation, is totally independent of all other samples of choice for the rest of the table he is about to create. All original equations is of equal length with one solution, which allows him to add each variable by position for every equation in the sample together with all the others, using XOR. Within each original equation, no operation is therefore performed between different positions. So all no. 1 position variables in his sample is merged together separately, all no. 2 position variables in the same sample are merged together separately, and so on. The solutions in his sample is merged together the same way. This will work because XOR is analogous to sum modulo 2, which sums up the 1:s from any number of equations, followed by modulo 2. Thus the operations on the variable side and the solution side are confirmative to each other. By repeating the merge for each of his sample, the initial receiver reaches his goal of constructing a new table of obfuscated equations.
[0024] Since, the solutions of this will constitute a new, symmetric key to use in combination with any independent protocol. Therefore there will be applications where the initial receiver is already using some symmetric scheme to encrypt a real language message or similar, based on this key. In FIG. 2 this choice is shown by the outgoing arrow splitting and going into the right rectangle below.
[0025] A third choice, not easily shown in the figure, is that the initial receiver now in parallel with his obfuscated table and a cipher also will send an entirely new, original table of completely independent equations, thereby acting “initial sender” in overlapping, consecutive scheme. This way, there will be no standing session key at all. Each symmetric key will be used only to encrypt and decrypt one single message. The initial receiver could even skip any use of symmetric keys and simply choose obfuscated equations to form a returning message, but because this do not allow independent parameter set to hide many solutions per equations, it will be of less practical value. The increased need for bandwidth is not motivated.
[0026] In any case, he will keep the solutions private, and return only the variable setup from his new table to the initial sender. The handling of the initial sender upon this returning information constitutes the tertiary phase ( 203 ) in the figure. The initial sender are now able to use the secret parameters of this, saved from start, to solve each obfuscated equation in the table. Because his way of obtaining these solutions are different from how the initial receiver got them, they are not easily available for any hacker. They therefore make up the common, symmetric key for the parties communicating. If there is a cipher attached to the returning table the initial sender will now be able to instantly use the key to solve it. Else the session of interaction by a symmetric scheme of choice will begin at this point, which is the communication phase ( 204 ).
[0027] In order to proceed to an example, first look at FIG. 3 and FIG. 4 to access the different parts of the matrix (the drawing in FIG. 4 is a continuation of the drawing in FIG. 3 ). The matrix can be pictured in many ways not shown here, for instance turned 90 degrees right and so on. The entire, filled matrix is shown as ( 301 ) also showing the empty right, upper corner, visible in all views. The initial sender's secret part of any equation is the parameterline ( 302 ). For practical purposes, multiple, independent parameterlines will be used, making up an entire parametertable ( 303 ). One single parameterline applied to a variableline ( 304 ) will equal one single solutionpoint. By ( 305 ) one example of a solutionpoint out of many is shown. An entire parametertable applied to an variableline will equal a solutionline ( 306 ). One single parameterline applied to a variableline, corresponding to a solution bit will make up an equationtotal ( 307 ). Multiple variablelines of equal length will form a variabletable ( 308 ). An entire parametertable applied to each of the equations in a variabletable will equal a solutiontable ( 309 ). The non secret part of each equationtotal which is sent from the initial sender to the initial receiver, but with all solutions included, is called an equation ( 310 ). The entire packet of equations sent will make up an equationtable ( 311 ).
[0028] FIG. 5 provides a detailed, exemplified view of the primary phase, with the preparations of the initial sender. A one parameterline only matrix, to easify understanding, is shown by ( 501 ) where intermediate sums on each rows are displayed before respective solution to the right. The choice of a 19×19 matrix is for illustration purposes only. The matrix is filled with binaries, beginning with random values for the parameterline and the variabletable. The random act of filling up the variabletable (only), can be replaced with a pseudo-random process, derived from a seed. If the initial sender and the initial receiver have a, non secret, pseudo-random generator in common, shared within the application, only the seed of the variabletable needs to be sent, saving bandwidth. The solutions still must be sent as non simplified information. For a hacker it will at this point be necessary to recreate the parametertable for any further conclusion, which for large tables will be virtually impossible. There are 2 N ways to pick a parameterline for an table of N variable positions. The non simplified information for this example is shown as ( 502 ) which is sent to the initial receiver.
[0029] FIG. 6 shows the same example operated by the initial receiver in the secondary phase from before. If an random-number generator is used, the table is rendered as a function of the generator acting on the seed received. By ( 601 ) is shown the equationtable, where equations of choice, hereby picked by the initial receiver, are marked according to the left column, illustrating every picked equation with an 1. The act of picking equations is an act of preferred randomness, equal to how the initial sender picked his parameters in former phase. The outcome of XOR operating over each position of the picked equations are shown at the bottom, with an intermediate sum displayed for each column. To the right the identical operation is performed over the solutions. The solution will never be sent. The information sent is shown as ( 602 ) and comprises one variableline for this example. The solutionpoint ( 603 ) is kept as part of the secret information pool. This means any third person, i.e man in the middle, cannot get hold of the solutionpoint without trying to find the original equations via brute force testing. Analogous to guessing the parameterline of the initial sender, this may take practically infinite time as there is again 2 M ways to obfuscate M original equations into a new one. In order to build a full information pool common for the initial sender and the initial receiver the latter will have to return an entire new, obfuscated variabletable, and therefore to repeat this step multiple times, ending up with multiple, independent, obfuscated equations of which the variabletable is returned but the solutiontable is kept secret.
[0030] FIG. 7 is a view over the retrieval of the solutionpoint i.e the tertiary phase from before. The initial sender have now got the variableline from the initial receiver. The parameterline from 501 is picked up and marked as ( 701 ). This secret information is applied on the variableline by boolean AND as for any of the original equations. The active variables of the equation are now summed together, displayed as an intermediate, after which modulo 2 is performed, i.e XOR over the length of the active variableline. The initial sender has now retrieved the identical solutionpoint ( 703 ) as the initial receiver added to his secret information pool as ( 603 ) before. The use of boolean NOT can be employed as a last operation possibility for the primary and secondary phase. This is analogous to imply a N+1 column in the former phase, using only XOR, where the last position of all variablelines is 1. The parameter is either 0 or 1. In the latter phase it is analogous to a M+1 equation with all variable positions occupied by 1, also using only XOR. However the solutionpoint then needs to be known which reveals the parameter of choice for the N+1 position in the former phase where NOT was formerly used, for a hacker. For the last phase, if the former mentioned parameter choice is implied, this still leaves the possibility of a doubled number of possible permutations for the same amount of information transferred. Intermingled operations with NOT and XOR are possible but will result in no more permutations as 2 NOT also in different stages cancels each other.
[0031] Presume use of boolean NOT over both phases. In the primary phase NOT is implied as an N+1 extra column while looked at as reversal of all bits in the secondary phase, for the sake of clarity. The initial sender randomly sets his parameter for N columns, as usual. If the number of 1:s in the parameterline is odd, the extra column parameter is set to 0. If the number of 1:s in the parameterline is even, the extra column parameter is set to 1. This means that the real number of 1:s for the entire parameterline, and therefore the number of active variablecolumns, will always be odd. The initial sender sends all equations to the initial receiver as usual. Now the initial receiver is able to employ NOT as a last step of any obfuscated equation. As the number of active variables are odd it means that it any variableline will either contain an odd number of 1:s and an even number of 0:s or vice versa. Negation over the entire variableline will therefore turn an odd number of 1:s into an even numbers of 1:s (former 0:s) and an even number of 0:s into an odd number of 0:s (former 1:s), or vice versa. The operation of NOT can be employed over the variablepoint (variableline) as well, why it is a equality preserving operation for any entire equation.
[0032] It is preferable that an application, using the scheme, includes use of an entire parametertable. In reality, only the equationtotal expresses full equivalence. This means that within the matrix of the initial sender, each of the parameterlines will act independently on the entire variabletable, engaging in M equationtotals for a table of M equations, resulting in one column in the solutiontable. Next parameterline in the parametertable will again act independently of the former, enforcing a new combination of columns in the variabletable, resulting in a new column in the solutiontable. The entire equationtable, including the solutiontable, is sent to the initial receiver. The initial receiver will now construct a new, obscured equation from the ones sent. He will perform XOR over each column in the solution table, meaning that each obscured equation of his will correspond to not only one single bit of secret information, but multiple. This will be the most effective way to create secret information out of a limited amount of public information.
[0033] FIG. 8 shows the view of a hacker, trying to find the original equations which resulted in the obfuscated variableline in our example ( 801 ), sent from the initial receiver. The hacker has also collected the original equations ( 802 ) sent by the initial sender and put the variabletable into his matrix. The solutiontable is not shown as it will be used only if the hacker is successful in finding the original variablelines used for the merge. Presume for demonstration purposes that NOT is never used. NOT will only result in him having to take into account an inverted variabletable as well. We will now assume that the hacker don't want to use brute force, but is trying to find a shortcut. One way would be to target rows with clustered 1:s for relevant columns. This would be to go for the fact that an obfuscated equation with a 1 in a position must have an original equation with an 1 on the same column. The column of sums ( 803 ) exemplify the output. If we compare this with ( 804 ) which is the solution the hacker searches for, but doesn't have, no such pattern occur, evident enough to save any real amount of computer power. Another way would be to perform a systematic hacking search, based on columns with a 1 in ( 801 ). These variablelines can be merged into a combinatorial testing scheme. This would mean only about half of the columns (obscure eq 1:s) would need consideration as well as only half of the rows for that column. But we can't eliminate even numbers of 1:s for that column, as the numbers interfere with the sums for other columns. Thus each of these positions can be either 0 or 1. We ends up with a permutation number which is obviously higher than 2 19 . So these kind of schemes will not help a hacker.
[0034] Leaving the Fig, a third consideration must be whether or not a brute force hacker is likely to stumble into some kind of other combination which works as well. For a table of the exemplified size, as to be expected for a quadratic table of any size, the average number of multiplets which makes a hit is 2. A brute force calculation for this small table will reveal this is true here, where try 365222 and try 524288 makes up combinatoric solutions and where 365222 is the variableline sent by the initial receiver as a binary number. As any solution will lead to working, original equations with enclosed solutions, this means a hacker will in average only do ⅔ the amount of tests he would otherwise have to do, to solve the problem. If the solutiontable is used as seed for a good, symmetric algorithm the hacker needs in principle all of it to put into the algorithm. This means he can't stop with his first hit but has to proceed down the path to solve further obfuscated equations. How many equations or how many parameter bits? In order to reach further conclusions the question of optimal number of parameterlines from a bandwidth/security perspective needs to be answered, easiest by looking at the extremes. One extreme is when only 1 parameterline is used. This means the primary sender is saving a lot of bandwidth as he only has to send effective solutions along with a seed for the common pseudo number generator. If the matrix is 256×256 lines times rows he send the seed, for instance 256 bits long, and the solutions, 256 bits. The primary receiver now has to use 256×256 obfuscated equations times their length to reach the level of a 256 bits security. Thus the initial senders bandwidth burden is 512 bits and the initial receivers bandwidth burden is 65536 bits.
[0035] The other extreme case, if we keep the number of parameterlines within the boundaries of the matrix, is 256 lines. Then the initial sender will have to use 256 bits for the seed and 256×256 bits for the number of equations times their solution length. The initial receiver can in this case return one obfuscated equation to describe a full 256 bits solutionline. In this case the initial senders bandwidth burden is 65792 bits and the receivers bandwidth burden is 256 bits.
[0036] As the function of bandwidth use is essentially multiplicative on each side the conclusion must be that the optimal number of parameterlines from a total bandwidth perspective in this case must be about √{square root over (256)}=16. For a crude approach there is no need trying to elaborate further while an absolute solution can be brought about by a equation setup where the number of average, estimated tries of a hacker trying to intervene either on the sender side or the receiver side, is the same.
[0037] For a rectangular 256×256 matrix (with 16 parameterlines and 256 obfuscated equations) he needs to make it through almost 75% of a full combinatorial set while instant testing on the symmetrical scheme will only need in average 50% of a full set. This means that the number of bits needed per amount of information for one of the asymmetric keys sent should be about 16×0.50/0.75=less than 16 times larger than for a symmetric key of same security standard if the pseudo random generator seed is not considered. | Two parties will engage in encrypted data communicating over a non secure channel. The encryption require a common session or consecutively updated key, not known by anybody else, and established without prior secrets. One of the parties, the initial sender, creates a table of multiple equations. Each equation contains parameters, known only by him, variables set to different values for different equations, and a solution. Each equation is true. He sends the information to the initial receiver who uses the original equations to form multiple new ones, thereby obfuscating their origin. The initial receiver keeps the solution side secret and return only the variable parts of his new equations. The initial sender receives the new equations and uses his hidden parameters to calculate the solutions. The solutions will now be known by the two communicating parties, but not easily available for an unauthorized interceptor of the communication. | 7 |
BACKGROUND
[0001] Synthetic Aperture Radar (SAR) is a radar technique that achieves the effect of a large aperture antenna by using a relatively small aperture antenna that is physically moved along a path. By combining the information from many pulses transmitted along the path, a SAR can synthesize the performance of a single large aperture antenna. SAR has been effectively used in airplanes and satellites to generate images of ground targets, for example.
SUMMARY
[0002] An optical SAR is disclosed that transmits an amplitude modulated optical signal toward a target. Forming a SAR image directly at optical wavelengths is difficult because platform motion must be measured with accuracy related to the wavelength of the optical signal, which is in the micron range. However, transmitting an optical signal that is modulated with a much lower frequency SAR waveform takes advantage of benefits of optical signals such as small aperture size and low weight while avoiding drawbacks such as mentioned above.
[0003] Modulation of optical signals may be performed using light emitting devices such as one or more light emitting diodes (LEDs) or laser diodes, for example. An LED or laser diode may be driven by a modulation signal via an amplifier so that the emitted optical signal intensity is amplitude modulated accordingly. The transmitted optical signals are reflected from a target, and the reflected optical signals are detected by light detecting devices such as photodiodes, for example. Photodiodes receive and automatically demodulate the reflected amplitude modulated optical signals. The optical SAR requires simple hardware to amplitude modulate an optical signal, and to recover the modulation from an amplitude modulated optical signal without the necessity of a coherent optical receiver.
[0004] The optical SAR may comprise a transmitter and a receiver. The transmitter is capable of generating an optical amplitude modulated signal by amplitude modulating the optical signal with the SAR waveform modulation signal and transmitting the amplitude modulated signal. The transmitted optical signal travels out to the target, and a portion of the transmitted optical signal reflects off the target and is received by the receiver. The receiver detects the received optical signal and demodulates it, thus recovering the original SAR waveform modulation signal. The optical SAR also may include a SAR computer that processes the received and demodulated SAR-waveform to generate an image and information such as target recognition, and moving-target information, for example.
[0005] The optical signal source may be any light-generating device that can be amplitude modulated such as the LED or laser diode examples mentioned above. The modulation waveform used to modulate the optical signal can be a linear chirp, for example. In general, any modulation waveform can be used, as long as its autocorrelation function is high at zero shift, and low everywhere else. Optical elements such as a polarizer, a lens, and a frequency filter such as a color filter may optically process the amplitude modulated optical signal before transmission and/or detection. The target may be interrogated with different optical signal properties that separate materials having different responses to the different optical signal properties, such as color or polarization. In this way, more accurate target recognition may be achieved.
[0006] Additionally, the bandwidth of the amplitude modulation signal may be set to be much higher than the bandwidth of conventional SAR signals, so that a dramatic increase of image resolution can be achieved. The optical SAR avoids object image variations resulting from capturing reflected light radiated from the sun, for example, that adversely affects optical imaging techniques. Sun angle, cloud cover, etc. all affect image properties that makes automated image interpretation difficult for optical imaging, but does not affect SAR imaging.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] Exemplary embodiments are described in detail below with reference to the accompanying drawings wherein like numerals reference like elements, and wherein:
[0008] FIG. 1 shows an exemplary optical SAR operation;
[0009] FIG. 2 shows an exemplary block diagram of an optical SAR apparatus;
[0010] FIG. 3 shows an exemplary block diagram of a SAR computer;
[0011] FIG. 4 shows an exemplary frequency domain diagram of an amplitude modulated signal having a carrier and 2 side bands;
[0012] FIG. 5 shows an exemplary frequency domain diagram of a carrier suppressed modulated signal with only 2 side bands;
[0013] FIG. 6 shows an exemplary block diagram of a transmitter and a receiver;
[0014] FIG. 7 shows an exemplary circuit diagram of a transmit-transducer;
[0015] FIG. 8 shows an exemplary circuit diagram of a receive-transducer;
[0016] FIG. 9 shows an exemplary block diagram of a waveform generator;
[0017] FIG. 10 shows exemplary linear chirp waveform diagrams;
[0018] FIG. 11 shows exemplary pseudo-random code waveform diagrams;
[0019] FIG. 12 shows an exemplary block diagram of a receiver;
[0020] FIG. 13 shows an exemplary block diagram of a transmit/receive (T/R) controller;
[0021] FIG. 14 shows an exemplary flow chart for a T/R controller process;
[0022] FIG. 15 shows an exemplary flow chart of a timer process;
[0023] FIG. 16 shows an exemplary flow chart of a transmitter process; and
[0024] FIG. 17 shows an exemplary flow chart of a receiver process.
DETAILED DESCRIPTION OF EMBODIMENTS
[0025] FIG. 1 shows an airplane 100 flying along a path 102 . An optical SAR 106 mounted in airplane 100 transmits an amplitude modulated optical signal in the form of a beam 108 toward target 110 of ground area 112 , and subsequently receives a reflected optical signal. The transmitted beam 108 has an illumination angle 116 designed to illuminate the target area of interest 110 . Optical SAR 106 performs the above transmit and receive operations repeatedly at points 114 along path 102 and processes the reflected optical signals resulting from a set number of points 114 to form an image and/or to generate other information such as moving target indications.
[0026] Optical SAR 106 forms beam 108 using optical signals instead of radio frequency (RF) signals to benefit from optical signal properties such as physical size and weight of required hardware. For example, as is well known in the art, the size of an antenna required to transmit a signal of a particular beamwidth is proportional to the wavelength of the transmitted signal. Because optical signals have a much smaller wavelength than that of RF signals, a transducer that transmits beam 108 can be physically much smaller than if RF signals were transmitted. Reduction in size leads naturally to reduction in weight.
[0027] Other benefits of using optical signals can also be obtained such as better image quality, improvement in moving target indication (MTI), avoidance of bandwidth interference with other communication and navigation systems operating in particular geographical areas, fully polarimetric SAR capability, and multi-spectral images. Each of these is briefly discussed below.
[0028] Images in a SAR that operate using RF signals (RF-SAR) suffer from image degradation known as Pulse Repetition Frequency Ambiguity (PRFA) which are artifacts caused by a lack of beam pattern control resulting in illumination of objects outside the desired image area. For optical signals, beam 108 can be precisely controlled and thus PRFA may be virtually eliminated.
[0029] Further, image quality may be degraded by scintillation caused by multiple scattering centers in a resolution cell that come in and out of phase over an aperture of the RF-SAR. This scintillation degradation may be reduced or eliminated by using a 50% bandwidth, i.e., a bandwidth that spans a full octave frequency range. This technique is difficult to achieve for RF-SAR due to antenna design and spectrum allocations. However, octave bandwidth is easily achieved for the modulation waveform of an optical SAR.
[0030] Another source of image degradation is “flashes” caused by dihedral or trihedral reflections from sides of buildings and then off the ground. Such reflections are possible for RF SARs because the buildings and ground act as smooth, mirror-like surfaces at RF wavelengths. At optical frequencies, very few things appear smooth, thus “flashes” may be significantly avoided and image quality improved.
[0031] RF-SAR may be used to detect moving targets. However, an illumination angle 116 for RF-SARs is relatively large, which only allows motion detection for targets moving at relatively high speeds. An illumination angle 116 for optical SAR 106 may be made much smaller than for an RF SAR, and thus provide detection of targets moving at much lower velocities.
[0032] RF signals transmitted by RF-SAR may interfere with communications and navigation equipment either onboard the platform operating the RF-SAR or operating in the geographical area near the target of interest. For example, FCC and/or FAA permission may be required before an RF-SAR can even be operated. In some situations, an RF-SAR is required to have gaps in their transmission spectrum, which degrades image quality. Using optical signals of optical SAR 106 eliminates this interference problem.
[0033] Polarities of optical signals may be easily controlled, so that beam 108 may be controlled to be horizontally, vertically or circularly polarized, for example, and light reflected from a target area may be received in specified polarities. Since polarization characteristics of various objects are different at different frequencies, optical SAR 106 may provide rich information regarding targets that cannot be obtained at RF frequencies.
[0034] In addition to polarization, multi- or hyper-spectral SAR may be used. Such a SAR would transmit optical signals at multiple wavelengths over the same aperture and directed toward the same target, thus producing a SAR image at each wavelength. This may be used, for example, to discriminate natural foliage from a camouflage net based on reflectivity differences at different frequencies. If red, green and blue optical frequencies are used, a true-color optical SAR image may be generated.
[0035] Optical SAR 106 also may take advantage of SAR properties to overcome electro-optics (EO) imaging drawbacks. For example, PO imaging forms images depending on reflected light or, in the case of InfraRed (IR) imaging, black body radiation. The appearance of objects in such images varies due to the angle of illumination, cloud cover, temperature variations, shadows, range, atmospheric conditions, etc. These changes in appearance make it difficult to implement automated image interpretation. However, SAR images do not suffer from the above variations. Thus, optical SAR 106 generated images are suitable for automatic target recognition and automatic change detection.
[0036] Advantageously, as is discussed below, optical SAR 106 receives the reflected signals and generates received data that conventional SAR systems could process. Thus, existing SAR processing may be applied to the received data generated by optical SAR 106 including large suits of exploitation tools already developed for SAR. For example, tools such as Coherent Change Detection (CCD), red-blue multi-view, moving target indication (MTI), automatic target detection (ATD), and various mensuration tools may be applied to the received data generated by optical SAR 106 .
[0037] FIG. 2 shows an exemplary block diagram of optical SAR 106 that may include a SAR computer 200 , a transmit/receive (T/R) controller 202 , transmitter 204 and receiver 206 . SAR computer 200 may be implemented by a general purpose computer or a specialized computer designed specifically for efficient processing of SAR related algorithms such as SAR image generation, automatic target recognition, movement target indication, etc. as mentioned above.
[0038] SAR computer 200 interfaces with an operator who commands an optical SAR operation by specifying beam aim-point, image size, and image resolution parameters, for example. SAR computer 200 generates operational parameters for T/R controller 202 to execute the commands and then waits to receive SAR-data from T/R controller 202 . T/R controller 202 initializes transmitter 204 and receiver 206 and starts the commanded SAR operation. Transmitter 204 transmits an amplitude modulated optical signal 208 as beam 108 that is directed at target 110 , for example. Receiver 206 receives reflected optical signals 210 , converts reflected optical signals 210 into digital SAR data, and forwards the SAR-data to SAR computer 200 via T/R controller 202 . When received, SAR computer 200 processes the SAR-data based on the operator commands. For example, the operator commands may have specified various types of displays to be generated and specific detection processes to be performed such automatic target recognition or motion target indication.
[0039] FIG. 3 shows an exemplary block diagram of SAR computer 200 that may include a SAR processor 300 , a SAR memory 302 , a T/R controller interface (I/F) 304 and an operator I/F 306 . These components are connected together by a bus 308 configured in a bus architecture. The bus architecture is shown as an example for ease of explanation. Other types of connections may be used as is well known in the computer architecture art. For example, depending on bandwidth requirements, SAR memory may require a dedicated direct memory access (DMA) port to support high data rates from T/R controller I/F 304 . SAR processor 300 may be implemented by using a general-purpose computer or specialized computers implemented by hardware components such as Application Specific Integrated Circuits (ASICs), PLAs, PALs, FPGAs, etc as is well known in the computer art. The functions needed for SAR processing may be implemented using software programs executing in either the general purpose or the special purpose computers. These programs may be stored in a computer readable medium and loaded into the computer for execution.
[0040] Additionally, SAR memory 302 may be any type of memory that can support the data rates that are required for a SAR operation. For example, SAR memory 302 can be implemented by using dynamic or static solid-state memory, programmable read/write memory and/or disk memory, for example. If the speeds of a mass storage is not fast enough, a form of cache using high speed memory can be used.
[0041] In the example shown in FIG. 3 , SAR memory 302 stores the SAR-data received from receiver 206 . When the SAR operation is completed for all points 114 of the commanded synthetic aperture, T/R controller 202 sends a completion message to SAR processor 300 through T/R controller I/F 304 . SAR processor 300 then begins to process the SAR-data to generate the commanded displays and other processing operations. Although the above example contemplates processing the SAR-data after the data is collected from all points 114 , SAR processor 300 may process SAR-data on the fly after sufficient data is collected. In this way, results of the SAR operation may be made available faster than if SAR processor 300 waited until data is collected from all points 114 . Thus, in the example shown in FIG. 3 , SAR memory 302 stores the SAR-data received from receiver 206 . As the SAR pulses are collected from points 114 of the synthetic aperture, the T/R controller 202 notifies SAR processor 300 through T/R controller IF 302 . SAR processor 300 then begins to process the SAR-data to generate the image and other SAR products.
[0042] Optical SAR 106 transmits an amplitude-modulated optical signal as beam 108 . As shown in FIG. 4 , amplitude modulation of a carrier signal generates 2 side bands one above and one below a carrier signal frequency, f c . Each of the side bands is separated by a modulation frequency, f m , from the carrier signal frequency f c . This double side band amplitude modulation (DSBAM) is different from other types of modulation such as double side band suppressed carrier (DSBSC) where the carrier signal is missing, as shown in FIG. 5 . This is a significant difference, because the DSBAM optical signal can be more easily generated in the transmitter, and more easily recovered in the receiver compared to DSBSC. In particular, the DSBAM signal can be generated by, for example, modulating the power that drives the light emitting device, without the need for components such as optical mixers. Also, the modulation can be recovered from a DSBAM signal using a simple envelope detector, without the need for a coherent local oscillator to regenerate the carrier as is required in DSBSC. Thus, the amplitude modulated optical signal permits relatively simple designs for transmitter 204 and receiver 206 .
[0043] The frequency of the optical signal is much higher than a frequency of SAR signals that modulate the optical signal. The resolution of SAR images is determined by the bandwidth of the transmitted SAR signal. The resolution of SAR images generated by optical SAR 106 can be superior to that of RF-SAR because the optical signal can be modulated at an extremely high rate. For example, optical signals generated by a laser can be modulated by a signal sweeping from between about 1 GHz to 6 GHZ, achieving a range resolution of about 3 centimeters.
[0044] An example of the transmitter and receiver is shown in FIG. 6 . Here, transmitter 204 generates an amplitude modulated optical signal by driving transmit-transducer 602 with a modulation signal output from a waveform generator 600 . Transmit-transducer 602 includes one or more devices such as semiconductor laser diodes 606 that are driven by amplifier 604 . Thus, light that is emitted by laser diodes 606 is a carrier signal that is amplitude modulated in accordance with the modulation signal and transmitted through one or more optical elements 608 as optical signals 610 to form beam 108 . Other types of light emitting devices may be used such as Light Emitting Diodes (LEDs), solid-state lasers, gas lasers, fiber lasers, etc. In fact, any light-emitting device in which the emitted light intensity can be controlled by the modulation signal at a desired SAR frequency can be used. The use of lasers may have some advantages, because they can be modulated at very high rates, and because they lend themselves to precise control of the optical beamwidth. However, it is not necessary that the lasers have long-term coherency, and if many laser devices are employed simultaneously for the purpose of increasing the transmitter power, the individual lasers do not need to be coherently synchronized to each other.
[0045] Reflected optical signals 622 may be detected by a receive-transducer 614 that includes one or more light sensitive devices 618 such as photodiodes, phototransistors, Charge-Coupled Devices, photo-multiplier tubes, etc. FIG. 6 shows photodiodes 618 receiving reflected optical signals 622 through one or more optical elements 620 . The intensity of reflected optical signals 622 is directly translated into output electrical signals by photodiodes 618 without the need for a mixer, optical down-converter, or a separately generated carrier signal. The output electrical signals are amplified by receive amplifiers 616 into received signals and then forwarded to waveform receiver 612 for conversion into digital signals as SAR-data for storing into SAR memory 302 via T/R controller 202 .
[0046] FIG. 7 shows a specific circuit example of one or more laser diodes 606 being driven by an amplifier 604 . Multiple laser diodes can be connected to a single amplifier to increase power of the transmitted beam. FIG. 8 shows a photodiode 618 , biased by biasing circuit 800 , outputting electrical signals to receive amplifier 616 . Here also, multiple photodiodes 618 may be used where multiple output electrical signals may be summed using a receive summing amplifier 616 and a summed value is output as the received signals to waveform receiver 612 .
[0047] Returning to FIG. 6 , optical elements 608 and 620 may include:
1. One or more lenses to focus beam 108 and/or reflected optical signals, 2. one or more polarization filters to generate beam 108 of a specific polarity or to receive reflected optical signals of a specific polarity, and 3. one or more spectrum filters to irradiate target 110 with one or more specific frequencies and/or to receive reflected optical signals at one or more specific frequencies that are matched to the transmit frequencies.
[0051] As discussed above, depending on the information needed regarding a target, specific optical properties of beam 108 may be required. Such properties are obtained by one or more optical elements 608 . For example, if multiple frequency ranges are desired to be simultaneously transmitted, transmitter 204 may use multiple amplifier/light emitters to concurrently transmit multiple frequency optical signals in beam 108 , such as red, blue, and green to form a color image, for example. In this case, light emitting devices having substantial energy in wavelengths different from each other may be used. Alternatively or in addition, optical elements 620 may receive reflected optical signals 622 through red, blue, and green filters, for example.
[0052] Optical elements 608 and 620 may be implemented by disposing frequency filters and/or light polarizers in the path of optical signals 610 emitted from light emitting devices such as laser diodes 606 or in the path of reflected optical signals 622 before reaching light sensitive devices 618 such as photodiodes 618 . For example, a specific frequency filter may be placed over each light emitting device. Although, for laser diodes 606 , filters are most likely not needed because these devices emit light in a specific frequency range. However, if light emitters that emit white light are used, then light filters could be used to filter the emitted light. The light filters can be placed over light sensitive devices 618 such as photodiodes to select a specific frequency range. If lenses are needed to set a beamwidth, for example, these may also be similarly disposed in the path of emitted optical signals 610 . Lenses may be used to receive reflected optical signals 622 . As is well known, lenses may have actuating elements such as motors to change focal lengths and other optical properties if needed.
[0053] Light emitting devices 606 and associated optical elements 608 may be disposed relative to a mirror that is mounted with motorized gimbals for the vertical and azmuth directions so that a launch direction of beam 108 may be set to aim at target 110 . Similarly, light sensitive devices 618 and optical elements 620 may be disposed relative to a mirror that is mounted with a second set of gimbals so that light from a specific direction may be received. As is well known, the gimbals may be set based on a platform position and orientation, and a location that beam 108 is to be aimed or a direction from which reflected optical signals 622 are to be received. As an example, U.S. Pat. No. 8,040,525, herein incorporated by reference, discloses a laser tracking device having a mirror mounted on motorized gimbals.
[0054] T/R controller 202 may control optical elements 608 and 620 by setting one or more values in optical-element-control-registers 607 and 619 , for example. Optical-element-control-registers 607 and 619 control optical treatments (focus, polarity, frequency range, e.g., red, blue or green) of beam 108 prior to transmission and a treatment of reflected optical signals 622 before detection by light sensitive devices 618 . T/R controller 202 may set values in optical-element-control-registers 607 and 619 while initializing transmitter 204 and receiver 206 prior to starting transmission of beam 108 .
[0055] FIG. 9 shows an exemplary block diagram of waveform generator 600 that may include a transmit-control-register 900 , a waveform source 902 , and a waveform selector 912 . Waveform source 902 includes signal generators 904 - 910 such as one or more of linear chirp generators 904 , pseudo-random code generators 906 , Barker code generators 908 , etc. Any type of signal generators may be used that is compatible with SAR applications such as a signal that has a high degree of auto-correlation, for example. Waveform generators 904 - 910 may be implemented by storing data representing a waveform in a memory and reading from the memory at a desired rate and starting at a desired location, for example.
[0056] FIG. 10 shows a linear chirp signal that is a signal whose frequency increases monotonically from a first frequency f 1 to a second frequency f 2 , as shown on the left side of the figure. The top right of FIG. 10 again shows a linear chirp modulation signal. The middle right of FIG. 10 shows an optical signal's amplitude after modulating it with the linear chirp. The optical signal appears dark because the frequency of the optical signal is much higher than a frequency of the SAR modulation signals. Thus, there are many cycles of the optical signal for each cycle of the modulation signal. The bottom right of FIG. 10 shows an optical signal that is modulated with an alternative binary version of the linear chirp. This type of modulation has similar performance in terms of SAR processing as the linear chirp, but may have the advantage of being easier to produce with some types of optical emitters.
[0057] FIG. 11 shows an alternative SAR waveform. A pseudo-random code example is shown where each bit of the pseudo-random code is allocated a symbol space of T time. Each symbol is represented by a fixed number of pulses. In FIG. 11 , an example of 5 pulses per symbol is shown, where each pulse has a period of t time. The pulses of each symbol modulate the optical signal as shown by the bottom waveform where each pulse includes many cycles of the optical signal because the frequency of the optical signal is far greater than that of the modulation signal. Thus, when the pseudo-random code is a 1, five pulses of the optical signal are transmitted, and when the pseudo-random code is a 0, no pulses are transmitted for 5 t pulse time periods.
[0058] Yet another alternative SAR waveform uses Barker codes, which are transmitted similarly as for the pseudo-random code but the 1s and 0s are arranged according to the Barker code scheme. The Barker code is defined as a sequence of N values of +1 and −1 as follows:
[0000] a j for j=1, 2, . . . , N such that
[0000]
∑
j
=
1
N
-
v
a
j
a
j
+
v
≤
1
[0000] for all 1≦ν≦N. This means that the autocorrelation of a barker code is between −1 and +1 for all non-zero shifts. Some known Barker codes are listed in the table below. If a binary 1 represents +1, a binary 0 represents −1, then the amplitude modulation using Barker codes is similar to the amplitude modulation using pseudo-random code except that the code bits are specified according to the Barker code scheme.
[0000]
Table of known Barker codes
Length
Code 1
Code2
2
+1 −1
+1 +1
3
+1 +1 −1
4
+1 +1 −1 +1
+1 +1 +1 −1
5
+1 +1 +1 −1 +1
7
+1 +1 +1 −1 −1 +1 −1
11
+1 +1 +1 −1 −1 −1 +1 −1 −1 +1 −1
13
+1 +1 +1 +1 +1 −1 −1 +1 +1 −1 +1 −1 +1
[0059] Returning to FIG. 9 , T/R controller 202 initializes transmit-control-register 900 by loading a bit pattern that arms one or more of signal generators 904 - 910 so that they are ready to start outputting modulation signals when a start command is received from T/R controller 202 . Similarly, another bit pattern is loaded that controls waveform selector 912 to connect the armed signal generators to desired amplifiers 604 in transmit-transducer 602 . For example, if transmitter 204 has a single amplifier 604 and if only linear chip is desired to be used as a modulation signal, linear chirp generator 904 is armed and waveform selector 912 is set to connect an output of linear chirp generator 904 to one amplifier 604 . When the start command is received, linear chirp generator 904 begins outputting the linear chirp modulation signal, and transmit-transducer 602 begins to emit optical signals 610 directed at target 110 .
[0060] If multiple signal generators 904 - 910 and/or multiple amplifiers 604 are desired to be used concurrently, then waveform selector 912 may be a M×N signal switch that is capable of connecting selected signal generators to appropriate selected amplifiers 604 . For example, if red, blue, and green frequency bands are all desired, these colors are to be concurrently transmitted, and each of the colors are to be modulated with a different modulation signal, then three of signal generators 904 - 910 and three amplifiers 604 may be selected.
[0061] FIG. 12 shows an exemplary block diagram of waveform receiver 612 that may include a receive-control-register 1200 , a frequency-down-converter 1202 , a signal selector 1204 , and an analog-to-digital converter 1206 . Received signals from amplifiers 616 may be connected directly to analog-to-digital converter 1206 for conversion into received SAR-data if the frequency range of the received signals is low enough. Current analog-to-digital converters may have speeds sufficient to process signal frequencies of up to about 1. GHz. If received signal frequency exceeds 1 GHz, then it may be necessary to first down-convert the received signals to a lower frequency more compatible with analog-to-digital converter 1206 . If down-converting is required, an output of frequency-down-converter 1202 is connected to analog-to-digital converter 1206 instead of the received signals.
[0062] Frequency-down-converter 1202 , signal selector 1204 , and analog-to-digital converter 1206 are controlled by data stored in receive-control-register 1200 . Bit fields may be dedicated to each of these components to control their functions. For example, frequency-down-converter 1202 may have capabilities to down-convert in different frequency ranges. Contents of receive-control-register 1200 may select a specific down-convert frequency amount. Additionally, frequency-down-converter 1202 may be turned off or put on stand-by mode if not needed to conserve power and reduce ambient noise. Signal selector 1204 is controlled by contents of receive-control-register 1200 to select the received signals or the output of frequency-down-converter 1202 as input to analog-to-digital converter 1206 . Analog-to-digital converter 1206 may be controlled by a start/stop signal to time the SAR-data output so that SAR-data of a desired range is obtained.
[0063] Waveform receiver 612 may include multiple frequency-down-converters 1202 , signal selectors 1204 and analog-to-digital converters 1206 to service multiple receive amplifiers 616 . For example, if red, blue and green reflected signals are to be detected concurrently, each of the colors is received by a different receive amplifier 616 . Received signals from amplifiers 616 are concurrently frequency down-converted, if needed, and converted to digital SAR-data by separate analog-to-digital converters 1206 . As a second example, two analog-to-digital converters 1206 may be used concurrently to capture the real and imaginary channels of a complex signal from amplifiers 616 or frequency-down-converter 1202 .
[0064] FIG. 13 shows an exemplary block diagram of T/R controller 202 that may include a T/R processor 1300 , a local memory 1302 , a timer 1304 , a DMA controller 1306 , a transmitter/receiver I/F 1308 , an optical elements I/F 1310 , and a SAR computer I/F 1312 . These components are coupled together by a bus 1314 configured in a bus architecture. As in FIG. 3 discussed in connection with SAR computer 200 , the bus architecture is shown as an example for ease of explanation. Other types of connections may be used as is well known in the computer architecture art. T/R processor 1300 may be implemented by using a general-purpose computer or specialized computers implemented by hardware components such as Application Specific Integrated Circuits (ASICs), PLAs, PALs, FPGAs, etc. as is well known in the computer art. The functions performed by T/R processor 1300 may be implemented using software programs executing in either the general purpose or the special purpose computers.
[0065] SAR computer 200 and T/R controller 202 may be implemented by a single hardware unit that performs all the required functions with the beneficial result of fewer components and fewer interfaces. The functions of the SAR computer 200 and the T/R controller 202 may be software implemented with hardware interfaces to transmitter 204 and receiver 206 .
[0066] An example of a SAR operation in T/R controller 202 may be as follows. After receiving a command for a SAR operation from SAR computer I/F 1312 , T/R processor 1300 initializes waveform generator 600 and waveform receiver 612 by loading appropriate instructions in the form of bit patterns into transmit-control-register 900 and receive-control-register 1200 . The instructions may be retrieved from a table stored in local memory 1302 . The table may be indexed by possible commands that may be received from SAR processor 300 . T/R processor 1300 similarly initializes optical-element-control-registers 607 and 619 to aim or focus beam 108 if needed and to set optical elements 608 and 620 to the various other optical treatment settings as may be commanded by SAR processor 300 .
[0067] T/R processor 1300 determines memory allocations in SAR memory 302 that is reserved for the upcoming SAR operation. The memory allocations may be determined by the command sent from SAR processor 300 , or determined by a generalized memory usage scheme. For example, a dedicated portion of SAR memory 302 may be allocated to operate in a swing buffer manner so that new SAR data is uploaded into one buffer while the another buffer is being read by the SAR processor 300 . T/R processor may initialize DMA controller 1306 with addresses and buffer sizes. These parameters may be stored in local memory 1302 , for example, so that SAR data received from waveform receiver 612 may be streamed into SAR memory 302 via SAR computer I/F 1312 .
[0068] T/R processor 1300 initializes timer 1304 by setting timer-values that is determined by a range of interest. A first timer-value sets a time from a start of transmission of beam 108 to a start of analog-to-digital converter 1206 to begin generating SAR-data. A second timer-value sets a time between the start of transmission to a stop of transmission of beam 108 . A third timer-value sets a time between the start of transmission to a stop of analog-to-digital converter 1206 to stop generating further SAR-data.
[0069] After timer 1304 is initialized, T/R processor 1300 issues a start command to timer 1304 , and waveform generator 600 . At this time, transmitter 204 may also respond to the start command by applying power to transmit-transducer 602 to begin transmitting beam 108 . Transmit-transducer 602 may have been turned off or placed in standby mode to save power, for example. But it is not necessary to place the transmit-transducer 602 in an off or standby mode because receiver 206 can be controlled to receive only the signals of interest regardless of a state of transmitter 204 . When the first timer-value expires, a start command is issued to analog-to-digital converter 1206 to begin generating the SAR-data. As analog-to-digital converter 1206 outputs portions of the SAR data, DMA controller 1306 uploads the outputted portions into SAR memory.
[0070] When the second timer-value expires, a stop transmission command is issued to waveform generator 600 to stop generating modulation signals. At this time, transmit-transducer 602 may be returned to off or standby mode or simply permitted to continue transmitting. Receiver 206 is independently controlled to receive the desired reflected optical signals. Analog-to-digital converter 1206 continues to output SAR-data portions because reflected optical signals 622 resulting from a desired portion of transmitted beam 108 may still be received. When the third timer-value expires, a stop command is issued to analog-to-digital converter 1206 because SAR data generation is completed. DMA controller 1306 also receives this stop command and stops streaming data from analog-to-digital converter 1206 to SAR memory 302 . When the commanded SAR operation is completed, T/R processor 1300 returns an operation-completed message to SAR processor 300 . After receiving the operation completed message, SAR processing may proceed to process the SAR-data to obtain desired information such as images and target data such as motion detection and automatic target recognition, for example.
[0071] The above example relates to a single transmission of a single beam. However, as discussed above, transmitter 204 and receiver 206 are capable of more complex SAR operations. For example, concurrent or fast sequential transmissions of multiple beams 108 of different optical frequency ranges and/or different optical properties such as different polarizations are possible. For fast sequential operation, the transmit-control-register 900 , receive-control-register 1200 , optical-element-control-registers 607 and 619 and DMA controller 1306 may be capable of instruction stacks arranged in a FIFO (first-in-first-out) configuration, for example. Similarly, timer-values in timer 1304 may be in multiple groups where each group controls one transmission event. In this way, a rapid sequence of beams 108 may be transmitted corresponding to each point 114 of a synthetic aperture.
[0072] FIG. 14 shows a flow-chart 1400 of an exemplary process for T/R controller 202 . In step 1402 , the process checks if a SAR command has been received from SAR processor 300 . If a SAR command has been received, the process goes to step 1404 . Otherwise, the process returns to step 1402 . In step 1404 , the process initializes DMA controller 1306 to upload SAR-data to allocated address locations in SAR memory 302 , and goes to step 1406 . DMA controller 1306 may be designed to follow a predetermined memory usage scheme, in which case initializing address allocation would not be necessary and the process arms DMA controller 1306 to be prepared for the upcoming SAR-data.
[0073] In step 1406 , the process initializes timer 1304 for sequencing transmitter 204 and receiver 206 to transmit beam 108 and receive reflected optical signals 622 for a range of interest, and the process goes to step 1408 . For example, first, second and third timer-values of timer 1406 may be set to the desired values. These timer-values determine the time to start analog-to-digital converter 1206 , the time to stop waveform generator 600 and transmit-transducer 602 , and the time to stop analog-to-digital converter 1206 relative to the start of transmission of beam 108 . In step 1408 , the process initializes transmit-control-register 900 , optical-element-control-register 607 of transmitter 204 , receive-control-register 1200 , and optical-element-control-register 619 of receiver 206 , and the process goes to step 1410 .
[0074] In step 1410 , the process issues a start command to timer 1304 , DMA controller 1306 and waveform generator 600 to begin a SAR operation, and the process goes to step 1412 . In step 1412 , the process checks if the SAR operation is completed. If the SAR operation is completed, the process goes to step 1414 . Otherwise, the process returns to step 1412 . In step 1414 , the process reports To SAR processor 300 that the SAR operation has completed, goes to step 1416 and ends.
[0075] FIG. 15 shows a flow-chart 1500 of an exemplary process of timer 1304 for transmission of a single beam 108 for a single frequency as opposed to a sequence of beams 108 of multiple frequencies. In step 1502 , the process checks if an initialize command has been received. If an initialize command has been received, the process goes to step 1504 . Otherwise, the process returns to step 1502 . In step 1504 , the process initializes all timer values such as first, second and third timer-values, for example, and the process goes to step 1506 . In step 1506 , the process checks if a start command has been received. If a start command has been received, the process goes to step 1508 . Otherwise, the process returns to step 1506 . In step 1508 , the process starts required timers, and the process goes to steps 1510 and 1514 concurrently. For example, for a single transmission of beam 108 of a single frequency, first, second and third timers (corresponding to the first, second and third timer values) are started. Also, here it is assumed that the third timer value is larger than the first and second timer values, because, normally, analog-to-digital converter 1206 should not be turned off before it was started and before the transmission of beam 108 has ended.
[0076] In step 1510 , the process checks if the first timer has expired. If the first time has expired, the process goes to step 1512 , stops transmission of beam 108 and then goes to step 1518 . Otherwise, the process returns to step 1510 . In step 1514 and concurrently with steps 1510 and 1512 , the process checks if the second timer has expired. If the second timer has expired, the process goes to step 1516 and starts analog-to-digital converter 1206 and goes to step 1518 . Otherwise the process returns to step 1514 .
[0077] In step 1518 , the process checks if the third timer has expired. If the third timer has expired, then the process goes to step 1520 . Otherwise, the process returns to step 1518 . In step 1520 , the process stops analog-to-digital converter 1206 and goes to step 1522 . In step 1522 , the process sends a message to T/R controller 202 that the SAR operation is completed and goes to step 1524 and ends.
[0078] FIG. 16 shows a flow-chart 1600 of an exemplary process for transmitter 204 . For ease of explanation, it is assumed that only a single beam 108 is being transmitted at a single frequency range. As noted above, if a more complex transmission is desired such as rapid sequential transmission of multiple beams at multiple frequencies, transmit-control-register 900 and optical-element-control-register 607 may in fact be stacks operating like FIFOs, for example. In such cases, a sequencer may be added to sequence the actions of transmitter 204 .
[0079] In step 1602 , the process checks if an initialization value has been received. If an initialization value has been received, the process goes to step 1604 . Otherwise, the process returns to step 1602 . In step 1604 , the process initializes the transmit-control-register 900 and optical-element-control-register 607 based on the initialization value and goes to step 1606 . The optical elements 608 changes to the settings loaded into the optical-element-control-register 607 , and waveform generator 600 selects the specific ones of amplitude modulation waveform generators 904 - 910 , and changes these components into active mode from off or standby mode if not already in the active mode. Also, waveform selector 912 is set to the selection indicated in transmit-control-register 900 . In step 1606 , the process checks if a start command has been received. If a start command has been received, the process goes to step 1608 , starts the selected one of amplitude modulation generators 904 - 910 and goes to step 1610 . Otherwise, the process returns to step 1606 . The amplitude modulation signal generated by the selected amplitude modulation generator 904 - 910 is connected to a selected amplifier 604 which modulates the amplitude of the optical signal emitted by one or more optical light elements 606 to generate an amplitude modulated optical signal. The amplitude modulated optical signal is transmitted through optical elements 608 to form beam 108 directed at target 110 .
[0080] In step 1610 , the process checks if a stop command has been received. If a stop command has been received, the process goes to step 1612 , places waveform generators 904 - 910 and transmit-transducer 602 to standby or off mode, goes to step 1614 and ends. As noted above, transmitter 204 may continue to function without affecting the SAR operation. However, in the interest of conserving power, the various components of transmitter 204 may be turned off or placed in a power saving mode such as a standby mode, for example. If a stop command has not been received, the process returns to step 1610 .
[0081] FIG. 17 shows a flow-chart 1700 of an exemplary process for receiver 206 . For ease of explanation, it is assumed that only a single beam 108 has been transmitted at a single frequency range. As noted above in connection the transmitter, if a more complex transmission is desired such as rapid sequential transmission of multiple beams at multiple frequencies, receive-control-register 1200 and optical-element-control-register 619 may in fact be stacks operating like FIFOs, for example. In such cases, a sequencer may be added to sequence the actions of receiver 206 .
[0082] In step 1702 , the process checks if an initialization value has been received. If an initialization value has been received, the process goes to step 1704 . Otherwise, the process returns to step 1702 . In step 1704 , the process sets receive-control-register 1200 and optical-element-control-register 619 based on the initialization value and goes to step 1706 . Analog-to-digital converter 1206 , signal selector 1204 and frequency-down-shifter 1202 are set according to the contents of receive-control-register 1200 . Optical elements 620 are set to states according to the contents of optical-element-control-register 619 . These components may have been turned off or placed in a standby mode to conserve power. In such a case, these components are placed in an active mode ready to immediately process reflected optical signals 622 . In step 1706 , the process checks if a start command has been received. If the start command has been received, the process goes to step 1708 . Otherwise, the process returns to step 1706 .
[0083] In step 1708 , the process starts analog-to-digital converter 1206 to begin generating SAR-data and outputting the SAR-data to DMA controller 1306 for storing in SAR memory 302 , and the process goes to step 1710 . In step 1710 , the process checks if a stop command has been received. If a stop command has been received, the process goes to step 1712 , stops analog-to-digital converter 1206 from generating further SAR-data, goes to step 1714 and ends. Otherwise, the process returns to step 1710 . Again, when the stop command is received, various components of receiver 612 may be turned off or placed in a standby mode to save power.
[0084] While the invention has been described in conjunction with exemplary embodiments, these embodiments should be viewed as illustrative, not limiting. Various modifications, substitutes, or the like are possible within the spirit and scope of the invention. | An optical SAR transmits toward a target an amplitude modulated optical signal. Modulation of optical signals may be performed using light emitting devices such as semiconductor laser diodes driven by a modulation signal so that the emitted optical signal intensity is amplitude modulated. Transmitted optical signals are reflected from a target, and reflected optical signals are detected by light detecting devices such as photodiodes that detect and automatically demodulate the reflected optical signals. Optical elements such as a polarizer, a lens, and a frequency filter such as a color filter may optically process the amplitude modulated optical signal before transmission and detection. This technique achieves the potential benefits of an optical SAR, such as high resolution, better image quality, and elimination of electromagnetic interference, while circumventing many of the problems traditionally associated with optical SARs, such as the requirement for optical coherence and extremely accurate platform motion measurements. | 6 |
BACKGROUND OF THE INVENTION
This invention relates to apparatus for the examination and surgery of both the anterior portions and the posterior portions of the eye.
For examination and operative therapy in the anterior portion of the eye, there have been available for a long time operation microscopes providing stereoscopic observation and which permit paraxial illumination with the instrument and oblique illumination by means of fiber optics or by slit illumination, and which are equipped with a pancratic variation of magnification as well as with connecting means for a co-worker's microscope and for documentary apparatus.
An observation microscope for several observers which has a pancratic system in the observation ray path is described in Fed. Rep. Germany patent No. 29 49 428 and in the corresponding U.S. Pat. No. 4,341,435 of Lang et al., granted July 27, 1982. An optical system of variable back focus and focal length which can be combined with the main objective of an operation microscope is disclosed in Fed. Rep. Germany Offenlegungsschrift (published but unexamined patent application) No. 32 02 075 A1 and in the corresponding European patent No. 0 085 308 and U.S. Pat. No. 4,525,042 of Muchel, granted June 25, 1985. The illumination ray path in an operation microscope is illustrated on page 222 of the English-language book "Handbook of Ophthalmic Optics," published 1983 by the Carl Zeiss firm of Oberkochen, West Germany, and on page 223 of the German-language edition of this book, published 1977 by the Zeiss firm under the title "Handbuch fur Augenoptik."
For the examination of the posterior region or fundus of the eye, ophthalmoscopes are known which make it possible, by direct or indirect observation, to illuminate and observe the retina of the eye, through the pupil, by means of mirrors or prisms. Such ophthalmoscopes are known, for instance, from pages 216 and 217 of the English-language edition of the above-mentioned Handbook.
SUMMARY OF THE INVENTION p The object of the present invention is to provide an instrument with which microscopic examination and microsurgery can be carried out on both the anterior and posterior portions of the eye. The anterior portions of the eye comprise the cornea, iris, and lens. In operative therapy on the posterior portions of the eye, so-called vitrectomy, the vitreous body and the retina are concerned.
This object is achieved, in accordance with the invention, by providing, in front of the main objective of an operation microscope, an ophthalmoscopic objective which images in an intermediate image plane each plane of the eye lying between the cornea and the fundus. The back focus and the focal length, as well as the magnification of the entire optical system of the apparatus, are infinitely variable. Also, there is provided a system for the lateral interchange of the pupils for simultaneous image inversion in the stereoscopic ray path, as well as a system for eliminating the reflections occurring in the illuminating ray path.
The combined use of the apparatus as an operation microscope for the anterior portion of the eye and as a stereoscopic ophthalmoscope for the posterior portion of the eye is assured by an achromatic aspherical ophthalmoscope objective having a focal length of f=25.7 mm, arranged in front of the main objective of an operation microscope. The ophthalmoscope objective preferably can be positioned at a variable distance from the eye of the patient. The ophthalmoscope objective provides an intermediale image of the object, which intermediate image is observed through the operation microscope.
For observation of the fundus, the ophthalmoscope objective is positioned at the distance of its focal length f from the cornea of the eye of the patient. The fundus is imaged into the intermediate image plane by the refractive power of the system consisting of the eye plus the ophthalmoscope objective. Regarding illumination, the exit pupil of the illuminating apparatus is focused in the pupil of the eye to be examined as is customary in the use of ophthalmoscopes.
For examination of the anterior portions or outer media of the eye, the ophthalmoscope is positioned at a distance of 2f from the cornea of the eye of the patient. The object is imaged by the ophthalmoscope objective with image inversion in the intermediate image plane. The ophthalmoscopic illumination then acts at the place of the object as a paraxial microscope illumination, and homogeneously brightens a field of about 15 mm in diameter.
By the combination of the main objective of the operation microscope with an optical system of variable back focus and focal length, such as is known in principle from the above mentioned U.S. Pat. No. 4,525,042 of Muchel and the corresponding German and European patent documents, the result can be obtained that the microscope has not only pancratic variation of magnification but also continuous objective focusing by which the fixed focal length of the main objective (e.g., f=225 mm) can be infinitely varied between f=150 mm and f=400 mm. This has the desirable result that the operating ophthalmologist can keep the operation microscope fixed in one position relative to the patient's eye and, from this fixed position, can bring into proper focus simply by operation of the objective focusing control, the entire region from the retina up to the posterior lens vertex. This is of particular importance for operation on the vitreous body (vitrectomy). Up to a myopia of -30 diopters of the eye of the patient, when using an ophthalmoscope objective with a refractive power of 40 diopters, a continuous change in focal length of about 85 mm is necessary in order to focus over all of said range. By suitable electronic controls and drives, the result is obtained that the changing of the linear magnification, caused by the changing of the back focus of the lens focusing, is eliminated by means of the pancratic variations of magnification. fication.
In this case, different linear magnifications can be selected. Similarly, the functional connection between objective focusing and pancratic focusing can be interrupted at any time, so that different planes in the region of the vitreous body can be observed with different linear magnification.
For the elimination of reflections, there is provided within the illuminating ray path, near the field stop, at least one glass plate which can be finely adjusted in three coordinates in space. Opaque pairs of points, which take stereoscopic observation into account, are applied to this plate. The pairs of points are so arranged that they eliminate the rays coming from the source of light which are reflected by the three surfaces of the ophthalmoscope objective into the two observation pupils and superimpose an image of the source of light on the image of the fundus.
By this optimalizing of the ray guidance which is necessary for the elimination of reflections, the illuminating optics is imparted the quality of a focusing optics in which, by increasing the illumination aperture, the shadow projection coming from the pairs of points is reduced to a minimum, so that the ophthalmoscope imaging does not have any loss of information.
One suitable embodiment of the invention provides means for coupling therapeutic laser radiation into the illuminating ray path. In this connection, the real intermediate image plane is shifted within the illumination ray path to the place at which the filament of the illuminating lamp is located during ordinary use of the instrument as an operation microscope or as a stereo ophthalmoscope. Within this plane there also lies the exit pupil of the laser radiation which is to be focused in the object and focal planes of the microscope for therapeutic purposes. The instrument is so constructed that by the placing on of a prepared double collector with incandescent bulb, a real image of the filament of the lamp is superimposed on the said intermediate image plane of the laser-light coupling.
In order to compensate for ametropias when giving laser treatment to the eyes of a patient, it is advisable, in accordance with refractometer principles, to provide in the illumination and laser ray paths an optical shift member which is moved synchronously with the internal focusing of the microscope, so that the intermediate image plane and the laser focus plane are always identical.
The advantages resulting from the present invention include, especially, the fact that the user has a single instrument for work on the cornea, the eye lens, or the retina, which instrument will provide, for all of these locations of work, a stereoscopic, erect, and laterally correct image, with a fully illuminated field of view. Another important advantage is that, due to the reflection-free observation of an ophthalmoscopic intermediate image, it is unnecessary for the eye which is to be operated upon to be contacted by an auxiliary optical means, such as a contact lens, in order to eliminate the refractive power of the cornea.
BRIEF DESCRIPTION OF THE DRAWINGS
In the accompanying drawings, which illustrate schematically a preferred embodiment of the invention:
FIG. 1 is a diagram showing the apparatus of the invention in the working position for use as a microscope;
FIG. 2 is a diagram showing the apparatus in the working position for use as an ophthalmoscope;
FIG. 3 is a view similar to FIG. 2 with the addition of laser coupling means; and
FIG. 4 shows a prism arrangement for lateral interchange of the pupils.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring first to FIG. 1, there is shown here a schematic diagram of the apparatus of the invention in the working position of an operation microscope, for examination of or surgery upon the external media of the eye. The eye of the patient is shown at 1, and the eye of the observer at 2. The observation ray path extends from the eye 1 of the patient, via the deflection elements 3 and 4, to the main objective 5 of the operation microscope, then through a conventional known optical system 6 of variable back focus and focal length, and along the ray path indicated at 35, via the deflecting elements 7, 8, 9, and 10, to a prism arrangement 11 for the interchange of the pupils, and thence to the conventional binocular viewing tube 33 of the operation microscope, and to the two eyes of the observer using the instrument. Only one eye of the observer is shown at 2, the second being hidden behind the one shown, in this direction of viewing, as well understood by those familiar with binocular viewing devices.
In the observation ray path, between the eye 1 of the patient and the reflecting element 3, there is placed the ophthalmoscope objective 15. This is an achromatic aspherical ophthalmoscopic objective having a focal length of f=25.7 mm. When the device is used for examining the external media of the eye (the mode illustrated in FIG. 1) it is positioned so that the ophthalmoscope objective 15 is spaced a distance of from 2f to 3f from the eye, as indicated by the numerical notation in FIG. 1. At the distance of 2f from the eye, it is possible, with slight pancratic magnification and thus with large depth of field, to view in its entirety the complete region from the retina up to the iris of the patient, even without actuation of the internal focusing mechanism.
To provide illumination of the object being viewed, there is a light source 20a which projects light through a condenser lens 20b, along an illumination ray path 34. It is reflected by the reflector element 17 to the previously mentioned reflector element 3, where the illuminating ray is again reflected to the ophthalmoscope objective 15 and passes through this objective to the object being examined, i.e., the patient's eye 1.
In addition to this illumination ray 34 from the source 20a, supplemental fiber-optical illumination shown schematically at 19 may also be provided.
With the optical system 6, the operation microscope, in addition to a pancratic variation in magnification of an expansion ratio of 6:1, also has a continuous objective focusing by means of which the fixed focal length (f=225 mm) of the main objective 5 can be infinitely varied between the limits of 150 mm and 400 mm.
Objective focusing and pancratic magnification are advantageously employed when an instrument in accordance with the invention is to be used merely for observation and therapy of the external media. In such case, the instrument is first positioned roughly so that the vertex distance from the lens 15 to the eye of the patient is 2f to 3f which, as above mentioned, is the distance schematically shown in FIG. 1. This is done by the mechanical means present, namely, by movement of the arm of the microscope stand, or by operating a conventional positioning motor (not shown) by means of a conventional external focusing control member (also not shown), in which connection the entire microscope is moved. The actual fine focusing necessary as a function of the object plane selected is then effected during the operation by the above-mentioned objective or internal focusing on the intermediate image produced within the instrument by the ophthalmoscope objective. During this focusing, the position of the instrument and thus also the position of the microscope eyepiece remains unchanged. The relatively large vertex distance from the instrument to the eye of the patient (two or three times the focal length of the ophthalmascope objective 15) gives sufficient room for manipulation to perform surgical acts on the outer eye. The ophthalmoscopic paraxial illumination is then advisedly supplemented or replaced by external oblique illumination, as for example by means of the fiber optics illuminating means 19.
In FIG. 2 the apparatus is placed so that the ophthalmoscope objective 15 is spaced from the eye 1 of the patient by the closer distance f, rather than 2f to 3f as in FIG. 1. This closer spacing is the working range used when the examination or surgery is in the region from the rear surface of the eye lens 22 to the fundus 24.
In order to obtain a sufficiently large stereoscopic base, the illumination is effected in the case of the stereoscopic ophthalmoscope by means of an elliptical mirror. By tilting the axis of the illuminating ray path 34 with respect to the axis of the observation ray path 35, the reflections by the eye lens 22 are eliminated. The reflections produced on the cornea are no longer disturbingly apparent, in view of the fact that an achromatized ophthalmoscope objective is used. Mirror and cornea are optically conjugated with each other. Injurious widening of the ghost reflection of the cornea is avoided by the achromatism.
In order to eliminate the reflections coming from the surface of the ophthalmoscope objective, a parallelsided plate 25 is introduced close to the field stop 25a and a decentralized pair of points is arranged on this plate. This pair of points is split into one pair of points for the virtual reflection and one pair of points for the two real reflections. A reflection-free imaging without disturbing visibility of the pairs of black points is obtained in the manner that the illuminating optical system is so changed that a higher illumination aperture becomes effective. The ophthalmoscope objective 15 focuses the fundus 24 at the intermediate image plane 24a.
The ophthalmoscope objective 15 is carried by a lens tube or mount 15a which may be moved in the direction of the double-headed arrow 23, toward and away from the patient's eye 1.
FIG. 3 illustrates the coupling of a laser into the stereoscopic operation ophthalmoscope. A laser 28 produces a laser beam which passes through an optical displacement member 29 and through a converging lens 28a to a semi-transparent mirror 27. The laser beam passes through this mirror 27 and here passes into the illumination beam which originates at the light source 26a. A real image of the filament of the lamp 26a is superimposed on the laser coupling via the double collector lens 26b. From this mirror 27 onward, the coupled beams (laser beam plus illuminating ray beam) pass through the field stop 25a and follow the same path (reflecting elements 17, 3 and objective 15) to the eye of the patient as in FIGS. 1 and 2.
For compensating for ametropia of the eye of the patient, the illuminating and laser beam path is preferably provided with an adjustable compensating slide member schematically shown at 18a, and the observation beam path is provided with a corresponding adjustable compensating slide member schematically shown at 18b. These two slide members are operatively interconnected by conventional connecting means for synchronous operation with the microscope internal focusing, so that the intermediate image plane and the laser focus plane are always identical.
FIG. 4 illustrates a prism system which may be used as the pupil exchanger indicated in general at 11 in FIGS. 1-3. In the arrangement of the prisms shown, the two stereoscopic ray paths 29 and 30 are interchanged with each other, with simultaneous turning of the image positions by 180 degrees, while maintaining constant the pupil spacing and the position thereof. This pupil interchange with simultaneous image inversion is necessary for observing the ophthalmoscopic intermediate image with the operation microscope.
The prism arrangement designated 31 and 32 consists, in each case, of four identical Porro prisms whose hypotenuses 33, 34 have fully mirrored (fully reflecting) action toward both sides. With this prism arrangement, there is obtained a small structural height with little loss in light, but on the other hand the optical wavelengths do not remain constant. If the optical wavelengths are to remain constant, a more expensive arrangement with rotatable prisms should be used.
For the optical system 6 of the operation microscope, there can be provided electronic controls and drives which see to it that the change in the linear magnification which a change in back focus of the objective focusing produces is eliminated by means of the pancratic variation of magnification. In this connection, different linear magnifications can be preselected. The functional connection between objective focusing and pancratic function can be eliminated at any time, so that different planes in the region of the vitreous body of the eye can be observed with variable linear magnification. The operation microscope can be positioned by electric motor means in three coordinates in space (x-y coupling, z-focusing coupling), the control commands being actuable, for instance, by the operation of a foot pedal. | In an instrument for the examination and surgery of the eye, an ophthalmological objective is combined with an operation microscope whose main objective is combined with an optical system of variable back focus and focal length. Every plane of the eye lying between the cornea and the fundus is imaged by the instrument at an intermediate image plane. In this way, with a single instrument, the operator can carry out work on the cornea, the eye lens, the vitreous body, and the retina. Since the instrument provides the observer with a reflection-free image, contact of the eye to be operated upon with an optical auxiliary means which eliminates the refractive power is unnecessary. | 0 |
[0001] This application claims the benefit of Korean Application No. 10-2002-0074067 filed on Nov. 26, 2002, which is hereby incorporated by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to a laundry drier, and more particularly, to a laundry drier control method in which a temperature variation rate per unit time is used to control drying time as needed.
[0004] 2. Discussion of the Related Art
[0005] A laundry drier is an apparatus for drying wet objects, e.g., clothes, after completion of a washing cycle or the like. FIGS. 1 and 2 illustrate a laundry drier according to a related art, with FIG. 2 showing a cross-section taken along a line I-I in FIG. 1.
[0006] Referring to FIGS. 1 and 2, a drier according to a related art is comprised of a body 100 having an entrance 101 at a front side in which a door 105 is installed, a drum 30 rotatably installed in the body and having a plurality of stirrers 30 a protruding from an inner circumferential surface of the drum, a motor 50 fixed to an inner side surface of the body to generate and transfer via a belt 60 a slow and directionally controllable rotational force with respect to the drum, first and second hot air passages 10 a and 10 b for guiding an air flow of external air ( 10 a ) to drum's interior to be discharged ( 10 b ) to the exterior of the laundry drier, a heater 20 installed inside the first hot air passage to heat the air therein, and an exhaust fan 40 for generating a forcible blowing force to discharge air through the second hot air passage and thereby draw in external air through the first hot air passage.
[0007] Referring to FIG. 3, illustrating a laundry drying method according to the related art, with wet laundry placed in the drum 30 , drying is initiated in a step S 10 to actuate each of the exhaust fan 40 , the heater 20 , and the motor 50 . As the exhaust fan 40 starts to operate, external air is drawn in through the first hot air passage 10 a, where it is heated by passing through the heater 20 and forcibly led into the drum 30 , to evaporate the water content of laundry placed therein. Thus, the drying action is realized by a negative blowing force of the exhaust fan 40 , whereby a circulation of air is achieved by drawing in external air through the first hot air passage 10 a and discharging the air through the second hot air guide passage 10 b. Meanwhile, the drum 30 is rotated according to a predetermined cycle, and the stirrers 30 a pull the laundry up one side of the drum's interior to fall back down into a lower area thereof. The laundry is dried in a step S 20 through the above-explained process.
[0008] As drying thus proceeds, if it is determined in a step S 30 that a predetermined time has passed, the heater 20 and motor 50 are stopped in a step S 40 . Here, the exhaust fan 40 continues to operate for a fixed predetermined time of say, five minutes, to perform a cooling of the interior of the laundry drier in a step S 50 , after which the door 105 may be opened. Thus, the cooling is performed according to a procedure similar to that of the steps S 20 ˜S 40 in which a constant operation is continued for a fixed duration.
[0009] As above, the laundry drier of the related art completes its assigned task by execution according to a predetermined time. That is, the drying procedure is performed for a fixed time, as set by the manufacturer, regardless of the amount or type of laundry being dried. Therefore, drying may be incomplete or excessive.
SUMMARY OF THE INVENTION
[0010] Accordingly, the present invention is directed to a method of controlling drying time of a drier that substantially obviates one or more of the problems due to limitations and disadvantages of the related art.
[0011] An object of the present invention, which has been devised to solve the foregoing problem, lies in providing a laundry drier control method which, by reading a temperature variation rate per unit time, dynamically varies the drying time according to the amount and type of an object being dried.
[0012] It is another object of the present invention to provide a laundry drier control method, by which drying is performed accurately according to the amount and type of object being dried.
[0013] It is another object of the present invention to provide a laundry drier control method, by which a proper drying is determined according to the amount and type of object being dried.
[0014] It is another object of the present invention to provide a laundry drier control method, by which improved drier operation can be achieved.
[0015] Additional features and advantages of the invention will be set forth in the description which follows, and in part will be apparent to those having ordinary skill in the art upon examination of the following or may be learned from a practice of the invention. The objectives and other advantages of the invention will be realized and attained by the subject matter particularly pointed out in the specification and claims hereof as well as in the appended drawings.
[0016] To achieve these objects and other advantages in accordance with the present invention, as embodied and broadly described herein, there is provided a laundry drier control method comprising steps of initiating a drying procedure; measuring a temperature variation rate per unit time over the drying procedure; calculating an overall drying time based on the measured temperature variation rate per unit time; and performing the drying procedure for the calculated overall drying time.
[0017] It is to be understood that both the foregoing explanation and the following detailed description of the present invention are exemplary and illustrative and are intended to provide further explanation of the invention as claimed.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this application, illustrate embodiment(s) of the invention and together with the description serve to explain the principle of the invention. In the drawings:
[0019] [0019]FIG. 1 is a cross-sectional view of a laundry drier according to a related art;
[0020] [0020]FIG. 2 is a cross-sectional view along a line I-I in FIG. 1;
[0021] [0021]FIG. 3 is a flow chart of a laundry drying control method according to a related art;
[0022] [0022]FIG. 4 is a block diagram of a laundry drier according to the present invention;
[0023] [0023]FIG. 5 is a graph of temperature over time, showing respective temperature plots for a relatively short drying time and a relatively long drying time, occurring in a laundry drier adopting a control method according to the present invention; and
[0024] [0024]FIG. 6 is a flowchart of a laundry drier control method according to the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0025] Reference will now be made in detail to the preferred embodiment of the present invention, examples of which are illustrated in the accompanying drawings. Throughout the drawings, like elements are indicated using the same or similar reference designations where possible.
[0026] A laundry drier control method according to the present invention reads a temperature variation rate per unit time to adjust a drying time of a drying procedure according to an amount and type of objects, i.e., laundry, being dried. That is, a drying procedure according to the method of the present invention is controlled such that a drying time is determined using a temperature variation rate per unit time, from the point of initiating the drying procedure.
[0027] Referring to FIG. 4, a laundry drier adopting the control method according to the present invention is comprised of an input unit 210 for inputting user commands, a display 220 for displaying the respective operational states of drying and cooling procedures based on the input user commands, a moisture sensor 230 for measuring the water content of laundry during the drying procedure and for outputting a sensed water content signal, a temperature sensor 240 for detecting an internal temperature during the drying and cooling procedures and for outputting a sensed temperature signal, a microcomputer 250 for controlling the drying and cooling procedures based on the sensed signals and user command input, to determine the state of the drying procedure and to control accordingly each of heater, motor, and exhaust fan drivers 260 , 270 , and 280 .
[0028] Upon initiating a drying procedure, the microcomputer 250 reads the temperature sensed by the temperature sensor 240 according to the drying time, whereby the temperature variation (slope) differs as the drying of a drying object proceeds. That is, the temperature varies sharply as the drying object begins to dry, varies more gradually when the drying object is substantially dried, and again varies sharply as the drying object nears a dry state.
[0029] Referring to FIG. 5, a time period Δt1 is a period for preheating the drying object, a time period Δt2 is a period during which the drying object is substantially dried at a peak drying temperature, and a time period Δt3 is a period for high temperature drying that continues for a predetermined time after the peak drying temperature. Based on such a drying procedure, a laundry drier adopting the control method according to the present invention differentially drives the heater and motor drivers 260 and 270 for the preheating and peak drying temperature periods (Δt1 and Δt2) and for the high temperature drying period (Δt3), according to whether a maximum drying temperature has been reached.
[0030] Specifically, a laundry drier adopting the control method according to the present invention determines a proper drying time by sensing the variation of the temperature per unit time as the drying procedure progresses as well as sensing any change in the temperature variation rate per unit time. The temperature variation rate per unit time, measured from the initiation of the drying procedure, decreases over time at a known rate, and after a predetermined time passes, the temperature variation rate per unit time increases when the drying object is nearly dry. This increase in temperature variation rate per unit time is used to calculate the remaining drying time and in turn an overall drying time. In other words, when a small laundry load is being dried, the drying time is reduced since the increase in the temperature variation rate per unit time occurs sooner than when a large laundry load is being dried, and vice versa.
[0031] Referring to FIG. 6, illustrating a laundry drier control method according to the present invention, with the drying object placed in the drum 30 , the input unit 210 is manipulated to initiate the drying procedure in a step S 100 , thus actuating the heater and motor drivers 270 and 280 . In doing so, the temperature sensor 240 immediately begins outputting a sensed temperature signal to the microcomputer 250 , indicating the drying temperature effected within the drum 30 , and the microcomputer determines a drying temperature variation rate per unit time. In a step S 200 , shortly after initiating the drying procedure, the temperature rapidly rises (high rate) to a predetermined temperature set according the input from the input unit 210 , and upon reaching the predetermined temperature, the drying of the drying object continues until there is no substantial variation (low rate) of the temperature. That is, based on the sensed temperature signal output from the temperature sensor 240 , the microcomputer 250 determines in a step S 300 whether the high temperature variation rate per unit time has been sufficiently reduced. A substantially increased rate of temperature variation indicates that the temperature inside the drier is rapidly rising, signaling that the drying object is nearly dry.
[0032] As soon as an increase in the temperature variation rate per unit time is detected, the remaining drying time is calculated in a step S 400 . In a step 500 , the drying procedure continues for the calculated remaining time, until completion in a step S 600 . The microcomputer 210 then controls the display 220 to display a “drying complete” status, and the operation of the heater and motor drivers 260 and 270 is stopped. Operation of the exhaust fan driver 280 continues for a cooling procedure according to a step S 700 .
[0033] Accordingly, the laundry drier control method of the present invention determines the drying time after an increase in the temperature variation rate per unit time with respect to the rate at the time of initiating the drying procedure. Hence, the overall drying time can be dynamically controlled, to differentiate the drying time according to the amount and type of laundry put in the drier. Thus, an improved operation of a laundry drier is achieved by determining a proper drying time whereby drying time is reduced when the drying object (laundry load) is small or can be dried quickly and is increased for larger loads or loads that may take longer to dry.
[0034] It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the invention. Thus, it is intended that the present invention cover such modifications and variations, provided they come within the scope of the appended claims and their equivalents. | A laundry drier control method reads a temperature variation rate per unit time, to enable drying according to the amount and type of an object being dried. The method includes steps of initiating a drying procedure; measuring a temperature variation rate per unit time over the drying procedure; calculating an overall drying time based on the measured temperature variation rate per unit time; and performing the drying procedure for the calculated overall drying time. The drying time determining step is repeated if a substantial increase in the temperature variation rate is detected. | 3 |
FIELD OF THE INVENTION
This invention relates to a gray water reclamation system and, more particularly, to a system for passively filtering the gray water that is generated by an individual household and reclaiming such water for use as required in the household's toilets and outside irrigation systems.
BACKGROUND OF THE INVENTION
Waste water generated by a household is typically classified as either black water or gray water. The former refers to water drained from toilets, dishwashers and garbage disposals and directed to a septic or sewage system. This water normally contains high counts of bacteria and is unsuitable for recycling. On the other hand, gray water, which is drained from bathtubs, showers, clothes washers and sinks, generally contains relatively small amounts of soap or detergent. As a result, gray waste water is usually safe to reuse, particularly in toilets and for outdoor irrigation.
Mcintosh, U.S. Pat. No. 5,106,493, discloses a known system for reclaiming and reusing gray water. Therein the waste water is actively pumped through a filter and to a holding tank, where chlorine is added. The water is then pumped as needed to a toilet tank and/or a hose bib. Unfortunately, the Mcintosh system exhibits a number of disadvantages. For example, it is unduly complex and requires both a sump and a pump to actively deliver the gray water through the filter and to the holding tank. Moreover, each gray water appliance is provided with its own solenoid driven valve for selectively discharging the water to either a gray water reclamation line or a sewer line. All of this equipment renders the system complex, expensive and quite susceptible to failure resulting from lightning strikes and other hazards. Furthermore, the chlorine that is added to the water is expensive, toxic and environmentally undesirable.
SUMMARY OF INVENTION
It is therefore an object of this invention to provide an improved gray water reclamation system featuring a simplified, yet efficient construction.
It is a further object of this invention to provide a gray water reclamation system employing an improved gravity filtration device that is arranged within the holding tank of the system.
It is a further object of this invention to provide a gray water reclamation system that reduces the use of harsh chemicals to decontaminate water in the holding or storage tank.
It is a further object of this invention to provide a gray water reclamation system that timely and effectively delivers reclaimed gray water, as needed, to various appliances.
It is a further object of this invention to provide a gray water reclamation system that stores and aerates reclaimed gray water when such water is not required.
It is a further object of this invention to provide a gray water reclamation system that is effectively integrated with the municipal water supply so that water service is not interrupted in the event of a shortage of gray water.
It is a further object of this invention to provide a gray water reclamation system that is effective for use in single family and multifamily residential households.
This invention features a gray water reclamation system, including a gravity water filter. There are gray water conduit means for receiving exclusively gray water from at least one household source and for passively delivering the gray water to the gravity water filter to remove impurities therefrom. Means are provided for temporarily storing the filtered gray water and there is at least one appliance that utilizes the filtered gray water. There are means for sensing that an appliance is in need of gray water and means, responsive to the means for sensing, direct the filtered gray water to the appliance in need of such water.
In a preferred embodiment the system may include a black water discharge conduit for discharging black water from at least one household source. A bypass conduit may communicably interconnect the gray water conduit means and the black water discharge conduit and valve means may be provided for selectively diverting the discharged gray water from the gray water conduit means to the bypass and black water discharge conduits.
Means may be provided for aerating the filtered gray water to reduce the level of bacteria therein. Such means for aerating may include spray jet means and aerator pump means for pumping the filtered gray water through the spray jet means. Alternatively, air may be pumped through the filtered gray water. The tank should be vented to provide a fresh supply of oxygen for aeration. Aerator control means may be provided for operating the aerator pump means at predetermined intervals. The aerator pump means may be automatically deactivated when the filtered gray water in the means for storing falls below a predetermined level.
The means for directing may include means, communicably interconnected between the means for storing and the appliance, for transmitting filtered gray water therethrough. Such means for directing may further include recycling pump means operably engaged with the means for transmitting, for selectively pumping filtered gray water through the means for transmitting from the means for storing to the appliance. The means for transmitting may include a pressure sensing tank. In such cases, the means for sensing may include pressure control means that activate the recycling pump means when the pressure tank falls below a first threshold pressure level and deactivate the recycling pump means when the pressuring sensing tank exceeds a second threshold pressure level that is equal to or greater than the first pressure level. Valve means may interconnect an appliance with a source of water independent of the filtered gray water. The pressure control means may close the valve means when the pressuring sensing tank is at or above a preliminary threshold level and may open the valve means when the pressure sensing tank falls below a secondary threshold level that is less then or equal to the primary pressure level. As a result, the independent source of water is communicably interconnected with the appliance. The means for transmitting may further include second filter means. Such second filter means may comprise at least one of a carbon, an ozone and an ultraviolet filter.
The gravity water filter and/or the recycling pump means may be mounted within the means for storing. Likewise, the spray jets or airhose, and the aerator pump means may be contained in the means for storing.
Preferred appliances that utilize reclaimed water according to this invention may include one or more toilets and an outdoor irrigation apparatus. Typically, the irrigation apparatus includes an underground osmosis pipe.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
Other objects, features and advantages will occur from the following description of preferred embodiments and the accompanying drawings, in which:
FIG. 1 is a schematic diagram illustrating a preferred gray water reclamation system in accordance with this invention;
FIG. 2 is a plan, partly schematic view of the principal outdoor components of the reclamation system;
FIG. 3 is an elevational side view of the underground storage tank with one wall removed to illustrate the gravity water filter, the recycling and aerator pumps, the aerator spray jets and the pump deactivation switch; and
FIG. 4 is an elevational, cross sectional view of a preferred gravity water filter that may be used in this invention.
There is shown in FIG. 1 a gray water reclamation system 10 that is designed for reclaiming the gray water drained from various household appliances and reusing such gray water in either indoor or outdoor applications. The household includes various appliances that generate waste water. A first group of appliances, including bathroom tubs and showers 12 and 14, bathroom sinks 16 and 18, kitchen sink 20 and washroom basin 22 generate exclusively gray water, which is the type of water to be reclaimed by system 10. Gray waste water typically includes small amounts of soap and detergent and is normally safe for filtering and reuse. A second group of appliances, including toilets 24 and 26, kitchen sink 28, and garbage disposal 30, discharge only black water, which is high in bacteria and is not reclaimed under any circumstances. A third group of appliances, including dishwasher 32 and clothes washer 34 are capable of discharging either black or gray water, depending upon the items being washed. For clarity, the appliances that drain gray water are represented by rectangles and the black water generating appliances are depicted by circles.
Each of the black water appliances drains into a black water line or conduit 36, that discharges into a conventional sewer or septic system. Dashed lines should be understood to represent a conduit which transmits only black water. Conversely, solid lines extending from the appliances represent gray water conduits. Each gray water generating appliance drains its waste water into a common gray water drain conduit 38. The gray water line discharges into an underground storage tank and primary filter apparatus 40. Dishwasher 32 and clothes washer 34 are provided with respective valves 41 and 42 that permit those appliances to drain into either the black water line 36 or the gray water conduit 38. Valves 41 and 42, which may comprise various types of conventional valves, are normally open to the black water conduit. However, they may be adjusted as required, such that water is drained from the dishwasher and clothes washer into gray water conduit 38.
As better shown in FIGS. 2 and 3, conduit 38 exits the house H from a point proximate ground level. A T-connector 43, FIG. 2, interconnects conduit 38 with one end of a bypass conduit 44. The opposite end of bypass conduit 44 is interconnected through a Y-connector 46 to black water conduit 36, which has exited through an adjacent wall of house H. Black water conduit 36 and gray water conduit 38, as well as all other conduits and pipes described herein, are preferably composed of PVC, although various other natural and synthetic pipe compositions known to those skilled in the art may be employed. A pair of slide valves 48 and 50 (also shown in FIG. 1) permit the gray water exiting house H to be directed either through gray water conduit 38 to storage and filter apparatus 40 or through bypass conduit 44 to black water conduit 36. In the event that servicing of the system is required, valve 48 is closed and valve 50 opened to direct the gray water to the black water conduit and from there to the sewer or septic system. Valves 48 and 50 are enclosed in a container or housing 52, best shown in FIG. 3. This housing is normally kept locked by the owner of the house until the positions of the valves require changing.
Conduit 38 is sloped or pitched slightly downhill from container 52 to tank and filter apparatus 40. More particularly, apparatus 40, shown in FIGS. 1-3, comprises an underground storage tank 54 that is constructed of fiberglass, steel, concrete or other durable and rugged materials. The tank preferably has a capacity that provides a suitable ratio of residential unit density to area being irrigated, although the precise size is not a limitation of this invention. An access hole 56 is provided at ground level through the top of tank 54. Gray water conduit 38 enters through an opening 57 in the side of tank 54. The conduit terminates in an open outlet 58. A pair of additional outlets 60 and 62 (FIG. 2) are formed transversely to conduit 38.
A primary gravity filter 64, FIGS. 1-3, is mounted to the interior vertical wall of tank 54 beneath outlets 58, 60 and 62 of conduit 38. More particularly, filter 64 is mounted to the tank by a bracket 66. As illustrated in FIG. 4, the filter comprises an outer pot 68 having an upper opening 70 and an interior cavity formed therein. Opening 70 is positioned just below the outlets of conduit 38. The pot may be formed of various materials such as plastic or PVC. A plurality of holes 72 are formed in the bottom and sides of pot 68 to conduct filtered gray water therethrough. A mesh fleer fabric 74 lines the inner wall of the pot. A layer of sand 76 covers the mesh layer 74 and a layer of gravel 78 covers the sand. Finally, a screen filter 80, which may comprise the type of multi-layered filter that is employed in air conditioning applications, covers gravel layer 78. In alternative embodiments multiple screen filters may be interspersed with gravel, fabric and sand layers as required. Gray water that is discharged from outlets 58, 60 and 62 into gravity filter 64 passes through the filter elements described above and collects on the bottom of tank 54. As a result, filter 64 removes large soap particulates, detergent and other relatively minor impurities from the gray waste water such that the water can be reclaimed and reused, as described more fully below.
Referring again to FIGS. 1-3, a recycling pump 82 and an aerator pump 84 are mounted to the floor of tank 54. An aerator pipe and spray bar apparatus 86 is operably connected to aerator pump 84 and includes a plurality of mist jets 88 that are pointed downwardly within the tank. Pump 84 circulates the filtered gray water through pipe 86 and sprays that water in mist form through jets 88. In alternative embodiments, an air pump, not shown, may be used to pump air through the gray water. This aerates and kills anaerobic bacteria in the filtered gray water and helps to decontaminate the water, which would otherwise accumulate bacteria if it were allowed to remain stagnant. A vent 85, FIG. 3, provides fresh air to the interior of tank 54.
Pump 82 removes filtered gray water from tank 54 through a transmission pipe 90 that exits the tank through an opening 91. A pump deactivation switch apparatus 92 deactivates pumps 82 and 84 when the water level in tank 54 drops below a predetermined level. In FIG. 1, switch apparatus 92 is shown schematically. When the water level is above a predetermined level, the switch is raised and closed to activate pumps 82 and 84. However, when the water level drops below the predetermined level, the switch is lowered as shown in phantom, and opened to disconnect the pumps. As a result, the pumps do not burn out due to lack of water in the tank. In FIGS. 2 and 3, switch 92 comprises a single station vertical switch such as is known in the pumping industry. The switch includes a reverse float element 94 that operates in a known manner. When the water level in the tank is above a desired amount, the float element 94 holds the switch closed and permits the pumps to operate. However, as the water level drops, the float element drops with it until eventually switch 92 opens. It should be understood that, in alternative embodiments, various other known switches, such as mercury float switches, microswitches and toggle switches may be utilized and mounted to operate pumps 82 and 84 in a manner known to those skilled in the art. If the gray water level in tank 54 exceeds a certain level, that water is permitted to drain through an opening 99 in the tank, which is connected by an appropriate conduit to the black water or sewer lines. As a result, the gray water level is not permitted to exceed the capacity of tank 54.
Transmission pipe 90 extends to above ground level and then through a gray water meter 100, a secondary filter 101, and a check valve 102. Filter 101 removes residual soap from the gray water. Gray water is transmitted through pipe 90 to either a first branch 104 that is communicably connected to a sprinkler valve manifold 106 or a second branch 108 that is connected to an activated carbon filter 110. A conventional pressure sensing tank 112 is communicably connected to pipe 90 and, more particularly, is connected directly to branch 108. Pressure tank 112 is constructed and operates in a manner known to those skilled in the art. In this application, tank 112 is provided with a pair of pressure control switches 114 and 116 that respond to sensed pressure levels in the manner described more particularly below. In alternative embodiments, a single pressure control switch may be employed. Switch 114 closes and provides a signal through a line 117 to activate pump 82 when the pressure in tank 112 falls below a first threshold level. Switch 114 opens and deactivates pump 82 when the pressure in tank 112 exceeds a second threshold pressure level that is equal to or greater than the first pressure level. An example that illustrates this operation is described below.
A sprinkler valve manifold 106 comprises three sprinkler valves 118, 120 and 122. Each sprinkler valve operates a respective underground irrigation sprinkler. These sprinklers typically feature an osmosis pipe that is disposed beneath a particular flower or vegetable garden, or other area to be irrigated. Although the gray water is effectively filtered by this system, it is preferred that the water reused in irrigation remain underground and not be sprinkled above ground. As a result, airborne viruses in the gray water (which may be generated by washing diapers or other causes) are kept below ground. Preferably, above ground sprinkling is performed by the municipal water supply, although such above ground sprinkling can be accomplished using gray water reclaimed as described in this invention. The osmosis pipes avoid clogging because residual soap is removed by filter 101.
In the event of a failure in the system or where a shortage of reclaimed gray water is otherwise experienced, the municipal water supply is readily accessed by system 10. A potable water supply 124 under city or municipal pressure is shown in FIGS. 1 and 2. A service pipe 126, FIG. 2, from supply 124 is directed into the house. A second service pipe 128, FIGS. 1 and 2, is interconnected with the gray water reclamation system. More particularly, pipe 128 is connected to gray water transmitting pipe 90 through a T-connector 136, a solenoid valve 130 and a vacuum air brake 132. From there, municipal water is directed through branch 104 to sprinkler valve manifold 106 and through branch 108 to second filter 110. Check valve 102 prevents municipal water from flowing back through pipe 90 into tank 54. Similarly, vacuum air brake 132 prevents gray water flowing through pipe 90 from backing up through line 128 into the potable municipal water supply 124. A water meter 134 records the volume of municipal water directed through pipe 128 for a particular task.
Valve 130 is electrically connected to pressure control switch 116. As long as that switch senses that the pressure in tank 112 is at or above a preliminary threshold pressure level, it holds valve 130 closed so that municipal water is not provided to pipe 90. However, when switch 116 senses that the pressure sensing tank has fallen below a secondary threshold pressure level that is less than or equal to the primary pressure level, it sends a signal to valve 130, which opens the valve and provides potable municipal water to pipe 90 and thereby to the underground irrigation system and filter 110.
As shown in FIG. 2, water supply 124 is also connected through T-connector 136 to above ground sprinkler lines 138, 140 and 142. These lines are maintained entirely separate from the gray water reclamation pipe 90. Each of the lines is directed to a particular sprinkling zone and various alternative number of lines may be employed. Each line is operated by opening a respective valve 144, 146 and 148. A meter 150 records the amount of municipal water required for above ground sprinkling.
An ultraviolet filter or ozone generator 152 is communicably connected to the outlet of carbon filter 110. From filter 152, return pipe 190 extends into house H and, as shown in FIG. 1, is communicably connected to each of the toilet tanks within the house. Such interconnections are formed in a conventional manner. Return pipe 190 provides reclaimed gray water to refill the toilet tanks as needed.
A number of controls are mounted to the side of house H. As shown in FIGS. 1 and 2, these include an aerator timer 154 that is programmed to start and stop aerator pump 84 at predetermined time intervals. A sprinkler valve control 156 is similarly programmed to open valves 118, 120 and 122 at predetermined time intervals. This directs either gray water from pipe 90 or municipal water from pipe 128 through respective lines 123, 125 and 127 to perform subterranean irrigation. A rain sensor 158 deactivates the sprinkler control 156 when sufficient rain is detected to make irrigation unnecessary.
A backwash is provided for periodically cleaning secondary filter 101. In particular, as illustrated in FIGS. 1 and 2, a line 161 interconnects potable municipal water supply 124 with filter 101. A second line 163 interconnects filter 101 with discharge conduit 44 that is itself connected to sewer line 36. To periodically clean fleer 101, a valve 165 is opened. As a result, potable water flushes filter 101 of residual soap that has been collected in the filter from line 90. The potable water and soap are transmitted through line 163 to line 44. During the backwash operation, an isolation valve 103 in line 163 is opened. This valve is opened either manually or remotely in a manner known to those skilled in the art. During normal operation while gray water is being pumped through line 90 by pump 82, isolation valve 167 is closed so that gray water is directed through the reclamation system and is not pumped out into the sewer line. One or more additional isolation valves, not shown, may be used to close transmission line 90 during the backwash operation. In other embodiments, the secondary filter 101 may be positioned at various other locations along line 90 after pump 82. For example, the filter 101 may be positioned below ground and prior to meter 100. Filter 101 may alternatively include a replaceable carbon element, which eliminates the need for a filter backwash.
During normal operation of system 10, gray water is drained from appliances 12, 14, 16, 18, 20, 22, (as well as from appliances 32 and 34 when their switches are appropriately set) into gray water conduit 38. The remaining appliances drain their waste water into black water line 36. The gray waste water is directed passively through conduit 38, which slopes from the house in a gentle, downhill manner, to storage tank 54. Sumps, pumps and other means for actively delivering the waste water to the tank are eliminated so that the risk of system failure is reduced. The gray water is discharged through outlets 58, 60 and 62 into gravity filter 64. Therein, the discharged gray water passes downwardly under the force of gravity through screen 80, gravel layer 78, sand layer 76, mesh layer 74 and perforated pot 68. The filtered gray water then collects on the floor of tank 54. Aerator timer 154 directs aerator pump 84 to operate a preset times; for example, from 7 a.m. to 4 p.m., seven days a week. As a result, water is circulated through sprayer apparatus 86 and sprayed by mist heads 88. This exposes the gray water to oxygen, which kills excess bacteria in the water.
Sprinkler timer 156 is programmed to open valves 118, 120 and 122 at predetermined times; for example from 2 a.m. to 4 a.m., three days a week. This eventually causes the pressure in tank 112 to drop below a predetermined level (e.g. 20 p.s.i.). Switch 114 closes and sends a signal over line 117 that activates pump 82. As a result, pump 82 draws filtered gray water from tank 54 and moves that water through pipe 90 to branches 104 and 108 for use by the underground irrigation system and toilets, respectively.
At the end of the predetermined time (e.g. 4 a.m.) one or more of the valves 118, 120 and 122 is closed by timer 156. This causes tank 112 to repressurize. When a second threshold pressure level (25 p.s.i.) is reached switch 114 opens to deactivate pump 82, which in turn stops delivering filtered gray water from tank 54 to manifold 106 and tank 112. Gray water continues to be filtered and collected in tank 54 and the entire sequence may be repeated so that gray water is delivered to the underground sprinkler system at the predetermined times. If, in the interim, adequate rain falls, sensor 158 keeps manifold 106 closed so that the pump 82 is not needlessly operated. If, as a result, the gray water level in tank 54 becomes too high, the excess water is drained through outlet 99. When the sensor dries out, the controller 156 is reactivated to operate the sprinklers, as described above.
Flushing household toilets 24 and 26 likewise tends the reduce the pressure in tank 112. When the pressure in tank 112 drops below 20 p.s.i., switch 114 activates pump 82. This causes gray water to circulate through filters 110 and 152. From there the filtered gray water is directed through pipe 190 back into the house to refill the toilets 24 and 26. At the same time, tank 112 repressurizes until it reaches 25 p.s.i. This again causes switch 114 to deactivate pump 82 until water is next required by either the underground sprinklers or toilets.
When the supply of gray water drops below a predetermined level in tank 54, float switch 92 deactivates pumps 82 and 84. This prevents the pumps from burning out due to lack of water in the tank. Because the pumps 82 and 84 are both deactivated, the pressure level in tank 112 gradually decreases in response to water usage by the toilets and underground irrigation system. Eventually, the pressure reaches a lowest desirable threshold setting (e.g. 15 p.s.i.). At that level pressure switch 116 closes and sends a signal over line 115, which opens solenoid valve 130. This connects potable water supply 124 with pipe 90 and provides city water to the underground sprinkler system or toilets, as required. Gradually, potable water supply 124 repressurizes tank 112 to 25 p.s.i. As a result, switch 116 closes valve 130 and disconnects water supply 124 from pipe 90. Valve 130 remains closed until the pressure in tank 112 again drops to 15 p.s.i., at which point the process is repeated.
The pressure threshold levels described herein are for illustrative purposes only. It should be understood that various pressure levels may be employed within the scope of the invention. Moreover, the preset times and durations are variable and may be programmed as required.
Although specific features of the invention are shown in some drawings and not others, this is for convenience only, as each feature may be combined with any or all of the other features in accordance with the invention. Other embodiments will occur to those skilled in the art and are within the following clams. | A gray water reclamation system is disclosed. The system includes a gray water filter and a gray water conduit for receiving exclusively gray water from at least one household source and passively delivering the gray water through a water filter to remove impurities therefrom. Filtered water is temporarily stored in an underground tank. A sensing apparatus such as a pressure tank determines when gray water is required by an outside irrigation system, inside toilets or other appliances. Suitable controls direct a pump to transmit water from the storage tank to either irrigation apparatus or, after further filtering, to appliances in need of water. | 4 |
BACKGROUND OF THE INVENTION
This invention relates to silicon-containing vinyl resin compositions. More precisely, this invention concerns vinyl resin compositions which are comprised of an organopolysiloxane and which possess lubricity, mold releasability, water repellency, abrasion resistance, gloss and processability.
Vinyl resins have been used widely in molded products, cast products, laminates, films, fibers, bonding agents, rubbers and paints. Since properties such as lubricity, mold-releasability, water repellency, abrasion resistance, gloss, processability and mechanical strength are required in many cases, attempts have been made to improve these properties by compounding additives such as silicone oil, waxes, higher alcohols and metal soaps with the vinyl resin. In particular, the addition of silicone oil can remarkably improve lubricity and mold-releasability of a vinyl resin. However, silicone oil is poorly compatible with vinyl resins so that there is the drawback that many problems occur due to the separation and leakage of silicone oil from the resins. In order to overcome these problems, both silicone oil and silicone rubber were added together to thermoplastic resins in Kokai Japanese Patent No. Sho 50(1975)-121344. However, leakage of silicone oil could not be prevented sufficiently. In addition, there was a drawback that the original characteristics of the thermoplastic resins were modified due to the addition of silicone rubber. In Japanese Patent No. Sho 52(1977)-6751, an organopolysiloxane having a --OCOR 1 group directly bound to a silicon atom, where R 1 represents substituted or unsubstituted monovalent hydrocarbon radicals, was added to vinyl chloride resins. In this case, since the --OCOR 1 group is directly bound to the silicon atom, hydrolysis occurs easily and gelation, occurring due to the presence of moisture in the air, markedly impairs the lubricity and appearance of the vinyl chloride resin. In Japanese Patent No. Sho 53(1978)-44178, an organopolysiloxane having a carboxyl group bonded to silicon via a Si--C bond was compounded with thermoplastic materials. In this case, the system is quickly corroded, due to the presence of carboxyl groups, and the functions of the compound are impaired or disappear, due to the occurrence of a reaction with basic compounds.
BRIEF SUMMARY OF THE INVENTION
It is an object of this invention to provide organopolysiloxane-containing vinyl resins which do not leak, i.e. do not exude organopolysiloxane. It is another object of this invention to provide improved vinyl resin which possess lubricity, mold-releasability, water-repellency, abrasion resistance, gloss and processability.
These objects, and others which will become apparent upon considering the following disclosure and appended claims, are obtained by mixing with a vinyl resin component an organopolysiloxane component which bears to least one silicon-bonded acyloxyhydrocarbyl radical.
DETAILED DESCRIPTION OF THE INVENTION
The present invention relates to a composition comprising (a) 100 parts by weight of a vinyl resin component and (b) from 0.01 to 20 parts by weight of an organopolysiloxane component having the formula ##STR1## wherein R denotes a substituted or unsubstituted monovalent hydrocarbon radical, R' denotes a divalent hydrocarbon radical, R" denotes an alkyl radical, A denotes an R radical or an R'OCOR" radical, m and n are each zero or a positive integer and the sum of m+n has a value of from 1 to 2000, there being at least one R'OCOR" radical per molecule of organopolysiloxane.
Vinyl resins used as component (a) in this invention are well-known materials and include vinyl homopolymers, such as polyvinyl chloride, polyvinyl acetate, polyvinyl alcohol, polyvinyl acetal, polyvinyl formal, polyvinyl butyral, polyethylenes, polypropylenes, polyacrylonitriles, polyacrylates, polymethacrylates, polyvinylidene chloride, polyvinyl fluoride and other vinyl homopolymers; vinyl copolymers, such as vinyl chloride/vinylidene chloride copolymer, vinyl chloride/methyl acrylate copolymer, vinyl chloride/methyl methacrylate copolymer, vinyl chloride/acrylonitrile copolymer, vinyl chloride/styrene copolymer, vinyl chloride/ethylene copolymer, styrene/acrylonitrile copolymer, methacrylate/acrylate copolymer, acrylonitrile/butadiene copolymer, acrylonitrile/butadiene/styrene copolymer, vinyl acetate/vinyl chloride copolymer, vinyl acetate/ethylene copolymer, vinyl acetate/acrylic acid copolymer, vinyl acetate/acrylonitrile copolymer, vinyl acetate/acrylate copolymer, vinyl acetate/maleic acid copolymer, vinyl acetate/styrene copolymer, vinyl acetate/vinyl alcohol copolymer, vinyl acetate/vinyl chloride/vinyl alcohol copolymer, vinyl acetate/vinyl chloride/ethylene copolymer and other vinyl copolymers; rubbery elastomers, such as ethylene/propylene rubber, ethylene/propylene/diene rubber, butyl rubber, acrylic rubber, acrylonitrile/butadiene rubber and chloroprene rubber and, copolymers of vinyl resins with resins other than vinyl resins. The vinyl resins used in this invention can also be mixtures of two or more types of the above vinyl resins. In particular, those which are most suitable among the vinyl resins mentioned above are polyvinyl acetate and its copolymers, polyacrylate and its copolymers, and polymethacrylate and its copolymers. In the case of these preferred copolymers the proportion of vinyl acetate or acrylate or methacrylate in the copolymer is at least 2 percent by weight.
Component (a) can have any form, such as a solution, an emulsion, a paste, a latex, a powder or a solid form.
Organopolysiloxanes used as component (b) in the compositions of this invention are expressed by the formula ##STR2## In this formula each R represents a substituted or unsubstituted monovalent hydrocarbon radical, such as alkyl radicals such as methyl, ethyl, propyl, octyl and tridecyl; cycloaliphatic radicals, such as the cyclohexyl radical; alkenyl radicals, such as vinyl and allyl radicals; aryl radicals, such as the phenyl radical, or said monovalent hydrocarbon radicals in which hydrogen atoms are replaced with halogen atoms or cyano radicals. It is not always necessary that all the R groups in a single molecule are identical. R' represents divalent hydrocarbon radicals, such as alkylene radicals, such as --CH 2 CH 2 --, --CH 2 CH 2 CH 2 --, --CH 2 (CH 3 )CH--, --CH 2 CH(CH 3 )CH 2 -- and --(CH 2 ) 4 --, or alkylene arylene radicals, such as --(CH 2 ) 2 --C 6 H 4 -- or --CH 2 -- 4 CH 2 --CH--CH 2 --C 6 H 5 , R" represents an alkyl radical, such as methyl, ethyl, propyl, decyl and octadecyl. A represents R or R'OCOR" radicals.
In the formula for component (b) m and n are 0 or integers of 1 or greater and m+n must be 1 to 2000. If m+n is 0, the effects on the lubricating ability and mold-releasing ability are poor, while if m+n exceeds 2000, the dispersibility of the component (b) in vinyl resins is reduced. Thus, m+n preferably ranges from 10 to 1000. If n=0 at least one A radical must be a R'OCOR" radical.
These organopolysiloxanes can impart lubricating ability, mold-releasing ability, water repellency, abrasion resistance and gloss to vinyl resins due to the presence of siloxane units and also can impart affinity and compatibility with vinyl resins due to the presence of one or more acyloxyhydrocarbyl radicals of the formula R'OCOR" so that the transparency of vinyl resins is not impaired and the procesability is excellent. Therefore, leakage of organopolysiloxanes from the vinyl resins does not occur. Since the R'OCOR" group is extremely stable, the various effects mentioned above are permanently maintained. In particular, in the cases when polyvinyl acetate and its copolymers, polyacrylate and its copolymers or polymethacrylate and its copolymers are used as vinyl resins, the compatibility and affinity with organopolysiloxanes having the R'OCOR" group are extremely excellent.
Organopolysiloxane component (b) is well known and can be prepared by any one of several methods. U.S. Pat. Nos. 2,550,205; 2,691,032; 2,770,633; 2,891,980; 2,906,735 and 2,922,806 are hereby incorporated herein by reference to show how to prepare organopolysiloxanes which are suitable as component (b) in the compositions of this invention. In particular, an organopolysiloxane having the formula CH 3 {(CH 3 ) 2 SiO} m {(CH 3 )(H)SiO} n Si(CH 3 ) 3 can be reacted with ##STR3## in the presence of a platinum-containing catalyst to prepare an organopolysiloxane component (b) for the compositions of this invention having the formula ##STR4##
The proportion of component (b) in the composition of this invention ranges from 0.01 to 20 parts by weight, preferably 0.1 to 10 parts by weight, based on 100 parts by weight of component (a).
The compositions of this invention can be prepared by simply mixing components (a) and (b) in any suitable manner. If a solvent is used, a solvent which is common to both components (a) and (b) is selected. If component (a) is available in an emulsion form, component (b) is emulsified using emulsifiers, such as sulfates of higher alcohols, alkylbenzene sulfonates and polyhydroxyalkylene adducts of higher fatty acids, and then emulsified component (b) is added to emulsion (a). If component (a) is available in a solid form such as chips or pellets, component (b) can be added when the chips or pellets are molded, or the chips or pellets can be melted and then component (b) added directly to the melt. That is, component (b) can be added to component (a) at any stage from the production process of component (a) to the final processing stage of the resin.
In addition to components (a) and (b), a variety of conventional additives can be compounded in the compositions of this invention. Examples are as follows: dry silica, wet silica, magnesium silicate, aluminum silicate, calcium carbonate, clay, mica, talc, titanium oxide, aluminum oxide, magnesium oxide, red iron oxide, magnetic iron oxide, various metal powders, carbon black, asbestos, glass fiber, glass beads, phthalates, phosphates, metal soaps, silicone oil, silane coupling agents, resins, isocyanates, waxes, higher alcohols, organic tin fatty acid salts, thermoplastic resins other than vinyl resins; such as polyurethanes and polyamides and polyesters, heat curable resins; such as melamine, phenol, urea, furan, xylene, alkyd, epoxy and silicone resins, natural rubbers and synthetic rubbers. In addition to these additives, the following known agents can be compounded in the compositions of this invention: fillers, plasticizers, stabilizers, flame retardants, U.V. absorbents, lubricating agents, surfactants, antistatics, antioxidants, antifungal agents, foaming agents, coloring agents and adhesiveness imparting agents.
The compositions of this invention can be used in all the uses of the conventional vinyl resins. For example, the compositions can be used in molded products, cast products, laminates, films, fibers, bonding agents, rubbers and paints. When the compositions of this invention are used as molded products, the products exhibit excellent mold-releasing ability and internal lubricating ability. When used as films or resin plates, the products exhibit excellent transparency and non-blocking character. When used as paints, the paint film exhibits excellent gloss, smoothness and water repellency. If magnetic powders, carbon black or dyes are compounded with components (a) and (b) constituting the compositions of this invention, the products can be used as excellent magnetic toners. If binders or other additives are compounded with the compositions constituting these magnetic toners, the products are suitable as magnetic paints for magnetic tapes and magnetic disks.
The following examples are disclosed to further illustrate, but not to limit, the present invention. All parts and percentages are on a weight basis. Viscosities were measured at 25° C.
EXAMPLE 1
The organopolysiloxanes that were used in this example, and their identifier symbols, are as follows:
______________________________________Organopolysiloxane Identifier______________________________________ ##STR5## A(1500 centistokes)Polydimethylsiloxane B(1000 centistokes)Methylphenylpolysiloxane C(1000 centistokes)Methyltridecylpolysiloxane D(900 centistokes)______________________________________
The vinyl resins that were used in this example, and their identifier symbols, are as follows:
______________________________________Vinyl Resin Identifier______________________________________Polyvinyl chloride (Sumilite SX-11) PVC(Sumimoto Chemical Industries, Ltd.)Vinyl chloride/5% vinyl acetate PVC/PVA-5%(Denka Vinyl M-70)(Denki Kagaku K.K.)Vinyl chloride/10% vinyl acetate PVC/PVA-10%(Denka Vinyl MM-90)(Denki Kagaku K.K.)Ethylene/28% vinyl acetate (Evalex) PE/PVA-28%(Mitsui Polychemical Co., Ltd.)Polyethylene (Mirason 24H) PE(Mitsui Polychemical Co., Ltd.)Polypropylene (Noblen H-501) PP(Sumimoto Chemical Industries Co., Ltd.)Polymethylmethacrylate (Sumipex LG) PMMA(Sumimoto Chemical Industries Co., Ltd.)______________________________________
Two amounts (0.6 parts and 1.5 parts) of each of the above-listed organopolysiloxanes were added to 100 part portions of each of the above-listed vinyl resins to provide 56 compositions (14 of this invention and 42 comparison) which were cast as films having a thickness of 1.5 mm. Each film was examined macroscopically for leakage before and after being heated at 70° C. for 7 days in a hot air circulation type oven. The results are summarized in Table I.
The leakage on the film surface was not found in the film prepared using Siloxane (A) specified in this invention and the film quality was excellent compared to those using the conventional silicone oils in the comparative examples. Especially when vinyl acetate resins, polymethacrylate resins, or polyacrylate resins were used as vinyl resins, the affinity and compatibility with Siloxane (A) were found to be particularly excellent. The reason for this seemed to be that these resins contain a group similar to the R'OCOR" group of the organopolysiloxane.
Based on the results mentioned above, the compositions of this invention were expected to be useful in the fields using combinations of vinyl resins and silicone oils and in particular, in toners used for electrophotography and static printing, and magnet forming phase of the magnetic recording media such as magnetic tapes and magnetic disks.
TABLE I______________________________________ Siloxane.sup.(1) Leakage.sup.(2)Vinyl Resin Before AfterIdentifier Identifier Parts Heating Heating.sup.(3)______________________________________PVC A 0.6 0 +" B " ++ x" C " ++ x" D " + x" A 1.5 0 +" B " ++ x" C " ++ x" D " + xPVC/PVA-5% A 0.6 0 0" B " ++ x" C " ++ x" D " + ++" A 1.5 0 0" B " ++ x" C " ++ x" D " + xPVC/PVA-10% A 0.6 0 0" B " ++ x" C " ++ x" D " + ++" A 1.5 0 0" B " ++ x" C " ++ x" D " + xPE/PVA-28% A 0.6 0 0" B " ++ x" C " ++ x" D " + ++" A 1.5 0 0" B " ++ x" C " ++ x" D " + xPE A 0.6 0 +" B " ++ x" C " x x" D " + x" A 1.5 0 ++" B " ++ x" C " x x" D " + xPP A 0.6 0 +" B " ++ x" C " x x" D " + x" A 1.5 0 ++" B " ++ x" C " x x" D " + xPMMA A 0.6 0 0" B " ++ x" C " ++ x" D " + ++" A 1.5 0 0" B " ++ x" C " ++ x" D " + x______________________________________ .sup.(1) Compositions containing Siloxane A are compositions of this invention; all others are comparative examples. .sup.(2) 0 denotes no leakage; + denotes a trace amount of leakage; ++ denotes slight leakage; x denotes significant leakage. .sup.(3) Heating was for 7 hours at 70° C.
EXAMPLE 2
Organopolysiloxane (A) used in Example 1 was added in a proportion of 1 part based on 100 parts of emulsion for paints primarily consisting of polyvinyl acetate (clear) and the mixture was mixed at a rate of 3000 times/min. with a homogenizer for 30 minutes. Subsequently, the composition was coated over an aluminum test panel (100 mm×100 mm×0.3 mm) to form a film with a thickness of about 100 μm and a transparent glossy film was formed by drying. When an adhesive tape (cellophane tape by Nichiban K.K.) was adhered on the coated film surface under pressure and peeled (this process was repeated five times), the peeling resistance was found to be extremely low and no abnormalities were found on the coated surface, indicating excellent non-blocking character. When the aluminum test panel having the formed film was boiled in boiling water for one hour, transparency and gloss were not dissipated.
The same test as mentioned above was conducted in the cases using dimethylpolysiloxane (B) and methylphenylpolysiloxane (C) used in Example 1 as comparative examples. Although both gloss and the non-blocking character were found to be identical to those found in the case using organopolysiloxane (A), the coated film was found to be cloudy after the boiling water test.
EXAMPLE 3
An organopolysiloxane (E) having a viscosity of 1200 centistokes and the following formula ##STR6## was added in a proportion of 0.6 parts and 1.5 parts to 100 parts of polyvinyl chloride or vinyl chloride/vinyl acetate copolymer with a vinyl acetate content of 10% used in Example 1, and the same experiment as in Example 1 was conducted. Leakage of organopolysiloxane (E) on the film surface was not found in any cases. | Vinyl resin compositions are disclosed which possess improved lubricity, mold releasability, water repellency, abrasion resistance, gloss and/or processability. These improvements are obtained by mixing with the vinyl resin a minor portion of an organopolysiloxane which bears one or more acyloxyhydrocarbyl radicals bonded to silicon in the organopolysiloxane. | 2 |
This application is a continuation of application Ser. No. 07/550,953 filed Jul. 11, 1990 now abandoned.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a communication apparatus having an abbreviated dial function such as a one-touch dial key.
2. Related Background Art
Conventionally, a communication apparatus such as a facsimile apparatus which stores dial data of a desired destination station in correspondence with a specific abbreviated dial key operation or a one-touch key operation, and calls the destination station using the dial data stored in a memory in accordance with the operation of the abbreviated dial key or the one-touch dial key to perform communication, is known.
In some apparatuses of this type, two dial data (e.g., a telephone number) can be registered for one destination. In such an apparatus, however, the use modes of the two dial data are limited
For example, two dial data are stored for a one-touch dial key, so that a telephone number of a destination facsimile apparatus is stored as the first dial data, and a telephone number of a destination telephone set is stored as the second dial data.
When the one-touch dial key is depressed while an original sheet is set, a call is generated using the first dial data, and facsimile communication is then performed. In this case, a call is generated for the purpose of performing a communication using the one-touch dial function. When the one-touch dial key is depressed while no original sheet is set, a call is generated using the second dial data, a speech signal of the destination station is monitored, and monitoring is interrupted upon off-hook, thus starting a speech communication. In this state, a call is generated for the purpose of performing a speech communication using the one-touch dial function. As applications associated with such a facsimile apparatus, U.S. Pat. Nos. 4,825,461 and 4,833,705 are known.
However, in the prior art, the use modes of two dial data registered for one destination are limited. For example, when a facsimile apparatus is used on a desk, such a function is very convenient. However, when a facsimile apparatus is equipped at a corner of a room to be commonly used by a plurality of users, the above-mentioned function is not so effective. That is, it is likely that a speech communication is performed using a telephone set on a desk but it is most unlikely that a user goes to a facsimile apparatus which is far from his desk to perform a speech communication.
In order to solve this problem, two one-touch keys are assigned to one destination, and speech and image communication dial data are respectively set in these keys. However, it is not effective as a method of using a limited number of one-touch keys.
The above problem is common to various communication apparatuses for controlling communications upon operations of predetermined abbreviated dial keys as well as one-touch keys.
SUMMARY OF THE INVENTION
It is an object of the present invention to improve a communication apparatus in consideration of the above-mentioned problem.
It is another object of the present invention to provide a communication apparatus which allows registration of a plurality of dial data for one abbreviated dial key, and can set a communication use mode of at least one dial data.
It is still another object of the present invention to provide a communication apparatus which allows registration of a plurality of dial data for one abbreviated dial key, and can realize an abbreviated dial function with a high degree of freedom.
The above and other objects of the present invention will be more apparent from the following description of the embodiment, and the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block diagram showing an arrangement of a facsimile apparatus according to an embodiment of the present invention; and
FIGS. 2, 2A, 2B show a flow chart showing a control operation of a control circuit of this embodiment.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
An embodiment of the present invention will be described in detail below with reference to the accompanying drawings.
In this embodiment, a facsimile apparatus will be exemplified. However, the present invention is not limited to a facsimile apparatus but may be applied to all the communication apparatuses having an abbreviated dial function such as a teletex or a telephone set.
FIG. 1 is a block diagram showing an arrangement of a facsimile apparatus of this embodiment.
In FIG. 1, a network control unit (NCU) 2 connects a telephone network to a terminal on the line to use it for a data communication, and performs connection control of a telephone exchange network, or switching to a data communication path, or holding of a loop.
A signal line 2a corresponds to a telephone line. The NCU 2 receives a signal on a signal line 26a, and if this signal has "0" level, it connects the telephone line to a telephone set side, i.e., connects the signal line 2a to a signal line 2b. Upon reception of the signal on the signal line 26a, if the received signal has "1" level, the NCU 2 connects the telephone line to a facsimile apparatus side, i.e., connects the signal line 2a to a signal line 2c. In a normal state, the telephone line 2a is connected to a telephone set 4 side for manual control or a speech communication by a CML relay in the NCU 2.
A hybrid circuit 6 separates transmission and reception signals. More specifically, a transmission signal on a signal line 8a propagates along the signal line 2c, and is sent onto the telephone line 2a via the NCU 2. A signal sent from a station on the other end of the line is input to the NCU 2, and is then output onto a signal line 6a via the signal line 2c.
A facsimile sender 8 comprises known circuits for image transmission, e.g., an image reader, an encoder, a modulator of a modem, and the like. A transmission signal from the facsimile sender 8 is input to the hybrid circuit 6 via the signal line 8a.
A facsimile receiver 10 comprises known circuits for image reception, e.g., an image recorder, a decoder, a demodulator of the modem, and the like.
In this embodiment, the arrangement and control of these image transmission and reception means are quite the same as those in the prior art, and a detailed description thereof will be omitted.
A calling circuit 12 generates a dial signal (e.g., dial pulses, a tone signal, or the like) adapted to a system of the line 2a. When a call instruction pulse is input from a signal line 26c, the calling circuit 12 generates a dial signal according to dial data input from a signal line 26b, and inputs it to the NCU 2.
A speech monitor circuit 14 monitors a speech signal. The monitor circuit 14 outputs a speech signal on the line via a loudspeaker or the like. The monitor operation of the speech monitor circuit 14 is enabled when a signal line 26d is set at signal level "1", and is disabled when it is set at signal level "0".
A console unit 16 comprises a keyboard including a ten-key pad, function keys, and the like. Key depression data on the keyboard is input to a control circuit 26 via a signal line 16a.
The console unit 16 has one-touch keys 25 including ten to several tens of keys. Depression data of these keys are also input to the control circuit 26. In this embodiment, two telephone numbers can be registered for one one-touch key 25.
A selector circuit 18 selects one of "substitute destination transmission" and "speech communication" functions for the second telephone number registered in a one-touch key 25 according to an operation state of key switches arranged on, e.g., the console unit 16 in association with the one-touch key 25. A "substitute destination" means another (second) telephone number of an identical destination station. When a facsimile apparatus of a destination station corresponding to the first telephone number cannot perform image reception, the apparatus of this embodiment performs transmission to the substitute destination.
A selection state of a use of a telephone number is output to the control circuit 26 via a signal line 18a. When the "substitute destination transmission" function is selected, the signal line 18a is controlled to signal level "1". When the "speech communication" function is selected, the signal line 18a is controlled to signal level "0".
A memory circuit 20 stores two telephone numbers for each one-touch key 25, and comprises, e.g., a RAM.
When dial data is stored in the memory circuit 20, a number of a one-touch key 25 (e.g., "01"), "*", a first telephone number, "*", and a second telephone number are input onto a signal line 20a by character codes, or the like, and a write pulse is generated onto a signal line 26e, thus writing these data in the memory circuit 20.
When dial data stored in the memory circuit 20 is read out, a number of a one-touch key 25 is input onto the signal line 20a, and a read pulse is input onto a signal line 26f, thus outputting two telephone numbers expressed by character codes o the like onto the signal line 20a while being divided by "*".
A display unit 22 comprises, e.g., a liquid crystal display, and is used for displaying time and an operation state and for monitoring input data upon registration of telephone numbers.
An original sheet detector circuit 24 comprises, e.g., a photosensor, and detects for communication control (to be described later) whether or not an original sheet is loaded on the original reader of the facsimile sender 8. When an original sheet is loaded, the original sheet detector circuit 24 sets a signal line 24a at signal level "1"; otherwise, it sets the signal line 24a at signal level "0".
The control circuit 26 comprises a microprocessor, a timer, and the like, and controls the operation of the entire apparatus constituted by the above-mentioned units. A control program for the control circuit 26 is stored in a ROM 26r.
The operation of the arrangement described above will be briefly described below.
In this embodiment, as a use of the second telephone number stored in the memory circuit 20 in association with the one-touch key 25, one of the "speech communication" and "substitute destination reception" functions can be selected.
These functions can be switched for all the one-touch keys 25 upon setup of the selector circuit 18.
A case will be described below wherein the "speech communication" function is selected by the selector circuit 18 as a use of the second dial data. An operator registers a telephone number of a destination facsimile apparatus as the first dial data of a one-touch key 25, and registers a telephone number of a destination telephone set as the second dial data.
When one of the one-touch keys 25 is depressed while the original sheet detector circuit 24 detects that an original sheet is loaded, a call is generated using the first dial data stored in the memory circuit 20 in association with the depressed one-touch dial key 25, and a facsimile communication is then started. In this operation, a call is generated for the purpose of a communication using the one-touch key dial function.
When one of the one-touch keys 25 is depressed while the original sheet detector circuit 24 does not detect an original sheet, a call is generated using the second dial data stored in the memory circuit 20 in association with the depressed one-touch key 25, a speech signal from a destination station is monitored using the speech monitor circuit 14, and a monitoring operation is interrupted upon off-hook of the telephone set 4, thus starting a speech communication using the telephone set 4. In this operation, a call is generated for the purpose of a speech communication using the one-touch key dial function.
A case will be described below wherein the "substitute destination transmission" function is selected as a use of the second dial data by the selector circuit 18.
An operator registers a telephone number of a destination facsimile apparatus as the first dial data of a one-touch key 25, and registers, as the second dial data, a telephone number of a nearby facsimile apparatus to which data is alternatively transmitted when the facsimile apparatus designated by the first dial data is busy.
When a one-touch key 25 is depressed while an original sheet is set, a call is generated using the first dial data, and a facsimile communication is then started unless a destination station is busy or cannot receive the incoming call. When the call is generated based on the first dial data, if the destination station is busy or cannot automatically receive the incoming call, a call is generated based on the second dial data stored in the memory circuit 20 in association with the corresponding one-touch key 25.
A facsimile communication is then started if it is possible. However, when the destination facsimile apparatus is busy, a call is generated again based on the first dial data stored in the memory circuit 20 in association with the one-touch key 25. This operation is repeated a predetermined number of times.
When no response is made for both the first and second dial data, a message indicating this is displayed. When no original sheet is set, a call is generated based on only the first dial data, and polling reception is performed.
The above-mentioned communication control will be described in detail below with reference to FIG. 2.
FIG. 2 is a flow chart of a control sequence by the control circuit shown in FIG. 1. The sequence shown in-FIG. 2 is stored in the ROM 26r.
According to a power-on operation, or the like, the control circuit 26 outputs a signal of signal level "0" onto the signal line 26a in step S32, thereby turning off the CML relay of the NCU 2, and connecting the line 2a to the telephone set 4 side.
In step S34, the control circuit outputs a signal of signal level "0" onto the signal line 26d, thus inhibiting a speech monitoring operation by the monitor circuit 14.
In step S36, the control circuit receives a signal from the console unit (signal output onto the signal line 16a), and checks if a registration mode of a telephone number associated with the one-touch keys 25 is selected. If YES in step S36, the flow advances to step S38, and the control circuit executes registration processing of a telephone number in the memory circuit 20 via the lines 20a, 26e, and 26f. An operation method and an edit method using the console unit 16, the one-touch keys 25, and the display unit 22 are known to those who are skilled in the art. In this case, two telephone numbers (or at least one telephone number) are registered for one one-touch key 25.
If NO in step S36, the flow advances to step S40.
In step S40, the control circuit receives a signal from the console unit, and checks if a one-touch key 25 is depressed. If NO in step S40, a different procedure is executed in step S41, and the flow returns to step S32. If YES in step S40, the flow advances to step S42.
It is checked based on a signal on the signal line 18a in step S42 if the "speech communication" mode is selected as a use mode of the second dial data stored in the memory circuit 20 in association with the one-touch key 25.
If it is determined in step S42 that the "speech communication" mode is selected, i.e., a signal of signal level "0" is output onto the signal line 18a, the flow advances to step S44. However, if it is determined in step S42 that the "substitute destination transmission" mode is selected, i.e., a signal of signal level "1" is output onto the signal line 18a, the flow advances to step S60.
In step S44, the control circuit receives a signal on the signal line 24a, and checks if an original sheet is set. When the original sheet detector circuit 24 detects that an original sheet is loaded, the control circuit outputs the first dial data stored in the memory circuit 20 in association with the one-touch key 25 onto the signal line 26b, and then generates a call instruction pulse onto the signal line 26c, thus generating a call based on the first dial data (step S46). In step S48, a facsimile communication is started.
If NO in step S44, the control circuit outputs the second dial data stored in the memory circuit 20 in association with the one-touch key 25 onto the signal line 26b, and then generates a call instruction pulse onto the signal line 26c, thus generating a call based on the second dial data (step S50). The control circuit then outputs a signal of signal level "1" onto the signal line 26d to enable the speech monitor circuit 14 (step S52).
In step S54, it is checked (based on a signal on the signal line 4a) if the telephone set 4 is set in an off-hook state within a predetermined period of time (e.g., 30 sec). If YES in step S54, the control circuit outputs a signal of signal level "0" onto the signal line 26d in step S56 to disable the speech monitor circuit 14, and a speech communication using the telephone set 4 is started in step S58. If NO in step S54, the flow advances to step S32.
In step S60, the control circuit outputs the first dial data stored in the memory circuit 20 in association with the one-touch key 25 onto the signal line 26b, and then generates a call instruction pulse onto the signal line 26c, thus generating a call based on the first dial data.
In step S62, it is checked if a communication allowable state is set. If YES in step S62, a facsimile communication is started in step S64. If NO in step S62, the flow advances to step S66.
In step S66, the control circuit receives a signal on the signal line 24a, and checks if there is an original sheet. If YES in step S66, the flow advances to step S68; otherwise, polling reception is to be executed. However, polling reception from a substitute destination is nonsense, and the flow advances to step S78.
In step S68, the control circuit outputs the second dial data stored in the memory circuit 20 in association with the one-touch key 25 onto the signal line 26b, and then generates a call instruction pulse onto the signal line 26c, thus generating a call based on the second dial data.
In step S70, it is checked if a communication allowable state is set. If YES in step S70, a facsimile communication is started in step S72. If NO in step S70, the flow advances to step S74.
It is checked in step S74 if neither of the destination stations (partners) designated by the first and second dial data are busy and neither of them respond, i.e., these stations are set in a manual receive mode. If YES in step S74, the flow advances to step S76 to display a message indicating this. If it is determined in step S74 that one of the destination stations designated by the first and second dial data is not set in the manual receive mode, the flow advances to step S78.
It is checked in step S78 if this step has been repeated three times. If YES in step S78, a message indicating this is displayed, and the flow then advances to step S32. If NO in step S78, the flow advances to step S60.
According to the above-mentioned sequence, when a call is generated using the one-touch key 25, a use mode of a second one of the two dial data stored in the memory circuit 20 in association with the one-touch key 25 can be switched between "speech communication" and "substitute destination transmission" modes according to selection of the selector circuit 18. When the "speech communication" mode is selected as the use, a communication or speech communication is automatically selected depending on the presence/absence of an original sheet like in the prior art described above.
In the "substitute destination transmission" mode, if a station called based on the first dial data cannot perform a communication, a call is generated based on the second dial data, and an image can be transmitted to a different terminal of the same destination station. Thus, if one terminal of a destination station cannot perform a communication for an extended period of time, image data can be transmitted as soon as possible.
In the above embodiment, the selector circuit 18 can switch the use mode of the second dial data stored in the memory circuit 20 in association with all the one-touch keys 25. However, the use mode of the second telephone number of each one-touch key may be controlled in units of one-touch keys. Since this control data must be set in units of one-touch keys, a control flag or the like may be set upon registration of the one-touch dial data.
In the above embodiment, two dial data are registered. However, three or more dial data may be registered. For example, three dial data are registered for each one-touch dial key, such that a destination facsimile number is stored as the first dial data, a destination telephone number is stored as the second dial data, and a substitute destination transmission number is registered as the third dial data. In this case, if an original sheet is set, a call is generated based on the destination facsimile number. If a terminal designated by the destination facsimile number is busy, a call is generated based on the substitute destination transmission number. If there is no original sheet, a call is generated based on the destination telephone number.
The above-mentioned technique can be applied to communication apparatuses other than a facsimile apparatus. The same control can be made in an apparatus which generates a call using dial data other than a telephone number. An abbreviated dial system is not limited to a one-touch key system, and the same control may be made as long as one operation means or method is assigned to a certain destination station.
The present invention is not limited to the above embodiment, and various other changes and modifications may be made within the spirit and scope of the invention. | A communication apparatus includes an abbreviated dial key, a memory for storing a plurality of dial data in correspondence with the abbreviated dial key, a control circuit responsive to a key input of the abbreviated dial key for selecting one of the plurality of dial data corresponding to the key, and generating a call based on the selected data, and a selector circuit for setting a communication use mode of at least one dial data of the plurality of dial data. | 7 |
This application is a divisional of application Ser. No. 08/156/029, filed on Nov. 19, 1993, now abandoned.
BACKGROUND OF THE INVENTION
The present invention relates to a supported solid catalyst which is capable of presenting high catalytic activity and can be used for the polymerization of conjugated dienes, to the method of preparing it, and to its use for the preparation of polymers and copolymers of conjugated dienes.
The use of lanthanides as polymerization catalysts for conjugated dienes is well known to the person skilled in the art.
Various catalytic compositions having a base of rare earths have been described, in particular with rare-earth halides. Thus, Sci. Sin. 13(8):1339, 1964, describes the use of yttrium trichloride and Belgian Patent No. 644 291 describes the use of cerium trichloride. However, by reason of the very poor solubility of these salts in the aliphatic or aromatic hydrocarbon solvents used as polymerization solvent, these catalytic compositions had a heterogenous character and a poor catalytic activity, which greatly limited their use on an industrial scale.
Various solutions have been described in order to overcome this drawback. Thus, the use of binary catalytic systems resulting from the reaction of a trialkyl aluminum compound with a rare earth trihalide complexed by electron donors has been described. The use of alcohol is described in the "Journal of Polymer Science - Polymer Chemistry 19:3345, 1980" and the use of tetrahydrofuran has been described in "Macromolecules 15:230, 1982".
As another solution, "Kaustschuk und Gummi Kunstoffe 22:293, 1969" has described the use of ternary catalytic systems resulting from the reaction of a rare earth carboxylate, particularly of neodymium, with a halogenating agent and a trialkyl aluminum compound, the halogenating agent possibly being a halogenated derivative of alkyl aluminum.
It has furthermore been proposed to use quaternary catalytic systems, as in European Patent No. 7027, which describes a catalytic system coming from the reaction of the reaction product of a Lewis base and a carboxylate of a metal of the lanthanide series with an organic compound of aluminum, an alkyl aluminum halide, and a conjugated diene.
Finally, more recently, the "Journal of Macromolecular Science - Chemistry, A 26(2 § 3):p.405-416, 1989" has described catalytic systems formed of neodymium complexes supported on a copolymer of acrylic acid with an olefin in the presence of an organic compound of aluminum and an alkyl aluminum halide.
SUMMARY OF THE INVENTION
The object of the present invention is a solid supported catalyst which is stable in time and is capable of having a high activity and of giving polymers and copolymers of conjugated dienes of desired microstructure without requiring difficult and/or complicated manners of operation for the carrying out thereof, such as those necessary with some of the catalytic systems previously mentioned. In particular, neither prepolymerization nor pretreatment is required.
Accordingly, the present invention provides a solid supported catalyst which can be used for the polymerization and copolymerization of conjugated dienes comprising metal atoms immobilized by a support, characterized by the fact that it comprises the reaction product
A) of a solid support in the form of magnesium dihalide,
B) a swelling agent of the support,
C) at least one compound of a metal selected from among the metals having an atomic number of between 57 and 71 or 92 in Mendelyeev's periodic table of elements, and, if the metal compound is not in halide form,
D) of at least one halogenation agent selected from the group consisting of a halogenated compound of aluminum represented by the formula X n AlR 3-n in which X represents chlorine, bromine, iodine or fluorine atoms, Al represents the aluminum atom, R represents an alkyl radical having one to fifteen carbon atoms, and n represents a number having a value of between 1 and 3, or a halogenated compound other than a halogenated derivative of aluminum having an exchangeable labile halogen, the reaction solid being free from the residual swelling agent after the reaction, plus
E) an organic derivative of aluminum represented by the formula X m AlR' 3-m in which X represents a halogen, R' represents a hydrogen atom or an alkyl radical having from one to eight carbon atoms, the three substituents however not all simultaneously representing a hydrogen atom, m represents the value 0, 1 or 2, necessarily present when the halogenation agent does not contain aluminum and optionally present when the halogenation agent contains aluminum.
The solid support used in the present invention is a support the lattice planes of which can move apart under the action of a swelling agent. The solid support used is a magnesium dihalide, and preferably magnesium dichloride. The magnesium dichloride is preferably anhydrous, but it may contain a very small proportion of moisture.
The swelling agent used in the present invention must be capable of spreading the lattice planes of the support and must be able to eliminate it after reaction with the support. As such, ethers are suitable, preferably tetrahydrofuran.
The metal compound or compounds immobilized by the support which is used in the present invention is any compound of a metal selected from among metals having an atomic number of between 57 and 71 or 92 in Mendelyeev's periodic table of elements, present in isolated form or in the form of a mixture of several metals of different atomic numbers. Preferred metal compounds are trivalent salts of cerium, lanthanum, praseodymium or neodymium, the commercial mixture "didymium", the tetravalent salts of uranium, and very particularly neodymium trichloride or a trivalent or tetravalent salt of a carboxylic acid having from 2 to 12 carbon atoms, or a mixed salt of a carboxylic acid having from 2 to 12 carbon atoms dissolved in the presence of two carboxylic acids of different molecular weight, one having from 2 to 12 carbon atoms and the other having from 2 to 5 carbon atoms, in a solvent which is preferably toluene. By way of example of carboxylic acids which can form a metal salt, mention may be made of acetic, butyric, n-hexanoic, n-heptanoic, n-octanoic, ethyl-2-hexanoic and versatic acids.
The metal may be present in variable amounts in the metal salt while conferring catalytic activity. Thus, the metal may be present in the metal salt within a range of 1% to 20% by weight, referred to the weight of the unswollen support. Preferably, it is present in an amount of 10% by weight referred to the weight of the unswollen support.
When the metal compound is present in the form of a carboxylate, it is necessary to use a halogenation agent in order to obtain a polymer or copolymer of conjugated dienes having a cis linkage of the monomer units.
The halogenation agent used in the present invention may be selected from the group consisting of:
a) a halogenated derivative of aluminum represented by the formula X n AlR 3-n in which the different terms have the significance indicated previously, as preferred examples of which we may cite dimethyl aluminum chloride, diethyl aluminum chloride, methyl aluminum dichloride, ethyl aluminum dichloride, aluminum sesquichloride, aluminum trichloride, diethyl aluminum iodide, and diethyl aluminum bromide,
b) a halide having an exchangeable labile halogen, such as, for instance, the alkyl mono- or polyhalides, the vinyl halides, the benzyl halides and preferably butyl chloride, tertiobutyl chloride, benzyl chloride, bromobenzene, and hydrochloric acid,
c) a metal halide which is not a derivative of aluminum, such as PCl 5 , ZnCl 2 and SnCl 4 .
When the halogenation agent is not a halogenated derivative of aluminum, the catalyst must comprise, in addition to the reaction product, an organic compound of aluminum represented by the formula X m AlR' 3-m in which the different terms have the meaning indicated above, while the presence of this compound is optional in the event that a compound containing aluminum and having the formula X n AlR 3-n is used as halogenation agent. By way of example of such compounds, mention may be made of diethyl aluminum hydride, diisobutyl aluminum hydride, triethyl aluminum, and triisobutyl aluminum.
The catalyst in accordance with the invention can be formed in accordance with two variants:
In accordance with a first variant, the catalyst is prepared by coprecipitation, carrying out the following steps in succession:
dissolving of the support in the swelling agent in the presence of the metal compound, at the boiling point of the swelling agent,
adding the resultant solution to an inert hydrocarbon solvent at low temperature, that is to say less than 0° C. and preferably equal to or less than -40° C.,
recovering the solid obtained by the reaction of the support with the metal compound,
washing the solid with an inert hydrocarbon solvent,
extracting and/or complexing the swelling agent of the isolated solid.
This elimination of the swelling agent can be effected by a drying carried out at room temperature and then at a temperature of more than 100° C., more particularly between 100° C. and 150° C., and preferably close to 120° C., possibly followed by an additional drying with an extraction or complexing agent of the swelling agent of formula X n AlR 3-n in which all the terms have the same meaning as given above. As preferred extraction and/or complexing agent of the swelling agent, diethyl aluminum chloride is used.
halogenation, as known per se, with a halogenation agent when the starting metal salt is a metal carboxylate,
washing with a hydrocarbon solvent of the halogenated reaction solid and then drying,
adding to the dried reaction solid an organic aluminum compound of formula X m AlR' 3-m in which the terms have the meaning previously indicated, when the halogenation agent is not a compound having the formula X n AlR 3-n in which the terms have the meaning previously given, in order to constitute the active catalyst.
This first variant is applicable whatever the nature of the salt in which the metal compound is present, whether it be a halide or a salt of a carboxylic acid, and whether the latter be present itself in the form of a simple salt or in the form of a mixed salt.
In accordance with a second variant, which is a preferred variant embodiment, the catalyst is prepared by carrying out the following steps in succession:
dissolving the support in the swelling agent at the boiling point of the swelling agent,
adding the resultant solution to an inert hydrocarbon solvent at low temperature, that is to say below -40° C.,
recovering the solid obtained by the reaction of the support with the swelling agent,
washing the resultant solid with an inert hydrocarbon solvent,
recovering the solid and then drying at room temperature and obtaining a swollen support having a molar ratio of support to swelling agent of 1:1.5,
suspending the swelling support in an inert hydrocarbon solvent,
adding to the suspension a solution of a metal mixed salt of a carboxylic acid having from 2 to 12 carbon atoms having reacted in an aromatic solvent at the boiling point of said solvent with two carboxylic acids of different molecular weight, one having from 2 to 12 carbon atoms and the other having from 2 to 5 carbon atoms,
heating, with agitation, at a temperature below the boiling point of the solvent, the swelling support and the metal carboxylate solution,
recovering the reaction solid,
extracting and/or complexing the reaction solid of the swelling agent by drying at room temperature and then at a temperature above 100° C., preferably between 100° C. and 150° C. and more preferably close to 120° C.,
recovering the supported solid metal component having a molar ratio of support to swelling agent of 1:0.5,
extracting the residual swelling agent and halogenating the metal component with a halogenation agent having a base of aluminum in solution in a hydrocarbon solvent,
isolating and drying at room temperature the solid halogenated reaction compound, that is to say, the catalyst.
Preferably, the extraction and/or complexing agent of the residual swelling agent and the halogenating agent are a single compound having the formula X n AlR 3-n in which all the terms have the meaning already given above.
When the halogenation agent is a compound satisfying the formula X n AlR 3-n , an organic compound of aluminum represented by the formula X m AlR' 3-m in which the different terms have the meaning given above can be included in the catalyst while its presence is indispensable as component of the catalyst when the halogenation compound does not satisfy the formula X n AlR 3-n .
The catalyst of the present invention permits the polymerization of conjugated dienes and the copolymerization of conjugated dienes with themselves in order to lead to homopolymers and copolymers which are stereospecific in cis. By way of polymerizable diene monomers, mention may be made by way of example of butadiene-1,3, isoprene, 2,3-dimethyl butadiene, pentadiene-1,3, and methyl-2-pentadiene-1,3.
The polymerization effected with the catalyst in accordance with the invention is carried out in manner known per se. It is preferably carried out in the presence of an inert alicyclic, aliphatic or aromatic hydrocarbon solvent conventionally used for the solution polymerization of conjugated dienes. Aliphatic solvents, in particular, heptane and cyclohexane, are preferred.
The polymerization or copolymerization reaction is carried out at a temperature between 40° C. and 120° C., preferably at a temperature close to 60° C. The polymers and copolymers obtained by this method in accordance with the invention can be grafted, functionalized or jumped as known per se and can be used as main mixture component which can be used for the manufacture of rubber articles, in particular automobile tires.
DESCRIPTION OF PREFERRED EMBODIMENTS
The following non-limitative examples are given by way of illustration of the invention. In all the examples, the operation is carried out under argon and the solvents are previously dried on a molecular sieve of 3A° with sweeping by argon; the inherent viscosities are determined at 25° C. in solution of 1 g/liter in toluene.
EXAMPLE 1
Preparation of the Catalyst
This example constitutes an embodiment of the catalyst according to the invention in accordance with the first variant method of preparation, namely by coprecipitation.
100 ml of tetrahydrofuran (THF) are introduced into a reactor, followed by 3 g of anhydrous magnesium chloride (MgCl 2 ) and 0.28 g of neodymium trichloride (NdCl 3 ). The reagents are heated at the boiling point of the THF until the magnesium chloride and neodymium chloride have completely dissolved. The resultant solution is then rapidly transferred into a 500-ml Schlenck tube containing 300 ml of heptane cooled to -50° C. by an ethanol/liquid-nitrogen bath. A solid is formed which is recovered and washed twice with 300 ml of heptane at room temperature.
After washing, the solid is dried under vacuum in a first step at room temperature and then at a temperature of 120° C. until it is of constant weight. 4.2 g of a green solid are obtained. This green composite product is then suspended in 20 ml of a molar solution of diethyl aluminum chloride in heptane and the reaction medium is agitated at 60° C. for 60 minutes.
The solid, which has assumed a blue color, is washed after recovery by simple decantation with 50 ml of heptane and then dried under vacuum at room temperature.
There are obtained 3 g of a blue reaction solid which constitutes the catalyst and which contains 1.4% by weight of neodymium, measured by atomic adsorption.
Method of Polymerization
A suspension formed of 300 ml of heptane, 1.8 ml of a molar solution of triisobutyl aluminum and 45 mg of the catalyst which was previously obtained are introduced into a reactor. Thereupon 11.5 g of butadiene are dissolved in this suspension at 15° C. and the temperature brought to 60° C. for 40 minutes, whereupon the polymerization is halted by the addition of a polymerization stopping agent as known per se (methanol/acetone mixture), and 0.7 g of polybutadiene having the following microstructure are recovered:
content of cis-1,4 bonds: 98.2%
content of 1,2 bonds: 0.7%
content of trans-1,4 bonds: 1.1%
and an inherent viscosity of 4.5 dl/g.
EXAMPLE 2
Preparation of the Catalyst By Coprecipitation
The catalyst is produced by repeating the method of operation of Example 1, with the exception of the neodymium trichloride, which is replaced by 2.8 ml of an 0.74 molar solution of neodymium tricaproate in tetrahydrofuran. The neodymium tricaproate is prepared by reaction of a slightly acid aqueous solution of NdCl 3 with an aqueous solution of sodium caproate under stoichiometric conditions; the product obtained is dried under vacuum at 50° C. and then dissolved in tetrahydrofuran.
Method of Polymerization
The manner of procedure of Example 1 is repeated, except that neodymium tricaproate is used and that the time of polymerization is 90 minutes. The catalyst used contains 0.4% by weight of neodymium. 0.2 g of polybutadiene are obtained having a content of cis-1,4 bonds of 98.1% and an inherent viscosity of 4.2 dl/g.
EXAMPLE 3
Preparation of the Catalyst by Coprecipitation
The catalyst is prepared by repeating the manner of operation of Example 1, except for the neodymium trichloride which is replaced by 5.95 ml of an 0.35 molar solution of neodymium tri(ethyl-2-hexanoate) in toluene.
Method of Polymerization
The manner of operation of Example 1 is repeated, except that 13.2 mg of the previously prepared catalyst which contains 4.8% by weight of neodymium are used and that the polymerization is halted after 60 minutes.
5.2 g of polybutadiene are obtained having a cis-1,4 bond content of 98.1% and an inherent viscosity of 3.9 dl/g.
EXAMPLE 4
This example constitutes a preferred embodiment of the catalyst of the invention, in accordance with the second, so-called "impregnation" variant.
Preparation of the Catalyst
A) Preparation of the swelling support with the swelling agent in order to obtain an MgCl 2 : 1.5 THF support.
2.7 grams of magnesium chloride are dissolved in THF in a Schlenck tube at the boiling point of said solvent until the MgCl 2 is completely dissolved. This solution is transferred rapidly into a second Schlenck tube containing 300 ml of heptane cooled by an ethanol/liquid nitrogen bath at -30° C. A solid is formed which is washed twice with 300 ml of heptane at room temperature, and then recovered and dried at room temperature. There are thus obtained 5.9 g of a white powder of MgCl 2 : 1.5 THF.
B) Preparation of the neodymium mixed salt: synthesis of anhydrous neodymium tri(ethyl-2-hexanoate) dissolved in the presence of ethyl-2-hexanoic acid and acetic acid in toluene. 40 ml of water brought to a temperature of about 50° C. and 1.6 g, namely 40 millimols, of caustic soda are introduced into an Erlenmeyer flask. After dissolving, 6.32 g, namely 44 millimols, of ethyl-2-hexanoic acid are added, and the temperature is brought to 90° C. for the time necessary in order to obtain complete dissolving. To the solution thus obtained, there is added, with vigorous agitation while maintaining the temperature at 90° C., a solution of hydrated neodymium trichloride previously obtained by dissolving 4.8 g of NdCl 3 .6H 2 O, namely 13.3 millimols of NdCl 3 , in 20 ml of water at 90° C., if necessary in the presence of hydrochloric acid so that the final pH of the NdCl 3 solution is between 1 and 2. After agitation for 30 minutes, during which the neodymium salt precipitates, the suspension is filtered and the neodymium salt is collected. This salt is washed abundantly with hot water and then dried under vacuum at 80° C. for 48 hours. 7.4 g of anhydrous neodymium tri(ethyl-2-hexanoate) are thereby obtained.
8.6 g, namely 15 millimols, of neodymium tri(ethyl-2-hexanoate) are placed in suspension in 50 ml of anhydrous toluene, whereupon 2.4 ml, namely 15 millimols, of ethyl-2-hexanoic acid and 0.86 ml, namely 15 millimols, of acetic acid are added. The medium is agitated with reflux of the toluene until the complete dissolving of the neodymium tri(ethyl-2-hexanoate). A solution of neodymium mixed salt is thus obtained.
C) Reaction of the support with the neodymium mixed salt.
2.8 g of the MgCl 2 : 1.5 THF support are added to a Schlenck tube containing 10 ml of heptane and the resultant suspension agitated, adding 3.0 ml of a solution of the neodymium mixed salt.
The temperature of the reaction medium is brought to 80° C. for one hour, during which the agitation is continued, whereupon the reaction solid which has formed is isolated and dried first of all at room temperature until it is dry, and then heated under vacuum at 120° C.
There are thus obtained 1.9 g of a green solid supported on MgCl 2 : 0.5 THF.
D) Synthesis of the catalyst supported on magnesium chloride.
The supported green reaction solid is reacted with 20 ml of a molar solution of diethyl aluminum chloride in heptane and the reaction medium is agitated at 60° C. for 1 hour, whereupon the solid which has assumed a blue color is recovered, washed twice by simple decantation with 50 ml of heptane, and then dried under vacuum at room temperature. In this way, the active catalyst which contains 5.7% by weight neodymium is obtained.
Method of Polymerization
The manner of operation of Example 1 is repeated except that 20.7 ml of the catalyst previously obtained are used and that the polymerization is carried out at 60° C. for minutes. 6.8 g of polybutadiene having a cis-1,4 bond content of 98% and an inherent viscosity of 4.1 dl/g are isolated.
EXAMPLE 5
This control example is intended to illustrate the importance of a swelling agent capable of spreading the lattice planes of the support.
Preparation of the Reaction System
In a metal Schlenck tube of a volume of 100 ml containing 55 g of steel balls of different diameters there are introduced 7.9 g of anhydrous magnesium chloride and 1 g of 1,2,4,5-tetramethyl benzene.
The mixture is agitated with a Dangouman vertical oscillation agitator having a stroke of 6 cm and operating with a frequency of 7 Hertz, namely with an acceleration close of 60 m/sec 2 for 4 hours.
TEST A:
Preparation of the Reaction System
To the support obtained there are added 10 ml of the neodymium mixed salt the preparation has been described in Example 4 under B. A solid is obtained which is recovered and then dried under vacuum at room temperature. This dried solid is then crushed for 4 hours, whereupon it is reacted with 20 ml dimethyl aluminum chloride by the method of operation described in Example 4 for step D. The solid reaction system is recovered.
Method of Polymerization
The manner of operation of Example 1 is repeated except that 55 mg of the reaction system previously obtained are used and that polymerization is effected for 1 hour before halting it. At the end of this time, only traces of polybutadiene are obtained.
TEST B:
Preparation of the Reaction System
The preparation is effected by repeating the manner of operation used for Test A except that the neodymium salt is replaced by 2 g of anhydrous NdCl 3 .
Method of Polymerization
The manner of operation of Example 1 is repeated except that 322.2 mg of the reaction mixture previously obtained with NdCl 3 are used and polymerization is effected for 1 hour before halting it. At the end of this time, there is obtained 1.5 g of a polymer the great majority of which is insoluble in the polymerization medium which is in the form of a gel.
EXAMPLE 6
This control example is intended to illustrate the importance of the neodymium mixed salt used in the preferred embodiment of the catalyst of the invention.
Preparation of the Reaction System
2.9 g of the MgCl 2 : 1.5 THF support are added to a Schlenck tube containing 10 ml of heptane, whereupon the resultant suspension is agitated, adding 0.66 ml of an 0.35 molar solution of neodymium tri(ethyl-2-hexanoate) in toluene, and using the method of operation described in Example 4 in steps C and D.
Method of Polymerization
The manner of operation of Example 1 is repeated, except that 33.1 mg of the reaction solid previously obtained with neodymium tri(ethyl-2-hexanoate) are used and polymerization is effected for 175 minutes. There is obtained 1.5 g of a polybutadiene of high content of cis bonds, namely a yield much less than with the neodymium mixed salt used in Example 4.
EXAMPLE 7
The purpose of this example is to illustrate the importance of the variation of the molar ratios of each of the two carboxylic acids of different molecular weight used to prepare the neodymium mixed salt.
Preparation of the Catalyst
Three tests are carried out in accordance with the conditions described in Example 4 with three solutions of neodymium mixed salt the concentrations of which, expressed in mole/liter and the neodymium contents by weight of the catalyst being set forth in Table 1:
TABLE 1__________________________________________________________________________Test (2Et--C.sub.5 H.sub.10 CO.sub.2).sub.3 Nd CH.sub.3 COOH (2Et--C.sub.5 H.sub.10 CO.sub.2 H).sub.3 Nd in %__________________________________________________________________________1 0.35 3.6-10.sup.-2 0.35 7.02 0.35 0.35 0.35 5.73 0.35 0.7 0.35 4.0__________________________________________________________________________
In the case of the solution prepared to carry out Test No. 3, there is observed the formation of a precipitate which is not used; it is the supernatant which is used for the reaction of halogenation and extraction and/or complexing of the swelling agent.
Method of Polymerization
The manner of operation of Example 4 is repeated with the three catalyst solutions previously prepared except that the weight of catalyst used and the duration of the polymerization are those indicated in Table 2, which also shows the amount of polybutadiene obtained with these three catalytic solutions and that of the control test carried out with the neodymium tri(ethyl-2-hexanoate).
TABLE 2______________________________________ Weight of Amount ofTest Catalyst in mg Time in Minutes Polybutadiene______________________________________1 31.3 25 4.9 g2 20.7 20 6.8 g3 56.3 50 4 gT 33.1 175 1.5 g______________________________________
It will be noted that it is advantageous to use a neodymium octoate solution in which the molar ratio of the two carboxylic acids of different molecular weights is close to 1.
EXAMPLE 8
This example illustrates a variant embodiment of another neodymium mixed salt which can be used in the preferred embodiment of the catalyst of the invention.
Preparation of the Catalyst
The manner of operation of Example 4 is repeated, except that butyric acid is used in place of the acetic acid and the following amounts of reagents are used:
neodymium tri(ethyl-2-hexanoate) in the form of an 0.35 molar solution of neodymium octanoate in toluene: 5 ml.
ethyl-2-hexanoic acid: 0.32 ml
butyric acid: 0.3 ml.
The catalyst obtained contains 6.3% by weight neodymium.
Method of Polymerization
The manner of operation of Example 1 is repeated, except that 22 mg of the previously prepared catalyst is used and that polymerization is effected for 15 minutes. At the end of the polymerization reaction, 3.6 g of polybutadiene are obtained.
EXAMPLE 9
This example illustrates a variant embodiment of a catalyst in accordance with the invention, in which the metal is cerium.
Preparation of the Catalyst
In this example, the same manner of operation is used as in Example 4, except that cerium is used in the place of neodymium and 9 ml of the cerium mixed salt obtained in a manner similar to the neodymium mixed salt are used. The solution of cerium tri(ethyl-2-hexanoate) used has a cerium concentration of 0.1 mol/liter, and the concentration of the two acids, acetic acid and ethyl-2-hexanoic acid, is also 0.1 mol/liter. The catalyst obtained contains 4.8% by weight of cerium.
Method of Polymerization
The manner of operation of the Example 1 is repeated, except that 94.5 mg of the previously prepared catalyst are used and that the polymerization is halted after 20 minutes. 2.8 g of polybutadiene are obtained.
EXAMPLE 10
This example illustrates a catalyst according to the invention in which the metal is uranium.
Preparation of the Catalyst
In this example, the manner of operation of Example 4 is repeated, except that uranium is used instead of neodymium and 9.5 ml of the uranium mixed salt obtained in a manner similar to the neodymium mixed salt are used. The catalyst obtained contains 3.3% by weight of uranium.
Method of Polymerization
Manner of operation of Example 1 is repeated, except that 98.1 mg of the previously prepared catalyst are used instead of the neodymium mixed salt and the polymerization is halted after 55 minutes. 5 g of polybutadiene are obtained. | A supported solid catalyst which can be used for the polymerization and clymerization of conjugated dienes having as its basis the reaction product of:
A) a solid MgCl 2 support,
B) an ether, preferably THF, as swelling agent for the support,
C) a metal salt selected from among metals having an atomic number of between 57 and 71 or 92 in the periodic table of elements and, if the metal salt is not a halide,
D) a halogenation agent selected from the group consisting of a halogenated compound of aluminum and a halogenated compound not containing aluminum, the reaction solid being free from the swelling agent, plus
E) an organic derivative of aluminum which is obligatory when the halogenation agent is not a halogenated compound of aluminum and optional when the halogenation agent is a derivative of aluminum.
Also, a method of preparing this catalyst. | 1 |
CROSS REFERENCE TO RELATED APPLICATION
This application is a divisional of U.S. patent application Ser. No. 09/326,484, filed on Jun. 4, 1999 now Pat. No. 6,207,962.
FIELD OF THE INVENTION
The present invention pertains, inter alia, to charged-particle-beam (CPB) microlithography apparatus and methods as used for transferring a pattern, defined on a reticle, to a sensitized substrate. Such apparatus and methods have especial utility in the manufacture of integrated circuits, displays, and the like. The invention also pertains to methods and apparatus for calibrating and adjusting a CPB projection-optical system and for aligning the substrate and reticle with each other for accurate pattern transfer. The invention also pertains to methods and apparatus for reducing thermal deformation of a member, such as the reticle or a movable stage, that defines an alignment or calibration mark.
As used herein, the term “reticle” pertains not only to reticles and masks that define an actual pattern to be transferred to a substrate, but also to aperture plates and the like as used in, for example: variable-shaped-beam projection-exposure systems, character projection systems, and “divided” projection-exposure systems. In “divided” projection-exposure systems, the reticle is divided or segmented into multiple “exposure units” (e.g., subfields, stripes, or other subdivisions) that are individually and sequentially exposed onto the substrate on which the images of individual exposure units are “stitched” together contiguously to form the complete pattern on the substrate.
BACKGROUND OF THE INVENTION
Various methods and apparatus are under current research and development for transferring, using a charged particle beam, a pattern defined by a reticle or mask onto a sensitized substrate by microlithography. Representative charged particle beams used in such systems include electron beams and ion beams. Electron-beam systems have been the subject of most such effort; hence, the following summary is in the context of electron-beam systems.
Charged-particle-beam (CPB) microlithography systems, such as electron-beam writing systems, offer tantalizing prospects of improved accuracy and resolution of pattern transfer, but exhibit disappointingly low throughput. Consequently, much contemporary research and development has focused on overcoming this disadvantage. Examples of various conventional approaches include “cell-projection,” “character projection,” and “block projection” (collectively termed “partial-block” pattern transfer).
Partial-block pattern transfer is especially used whenever the pattern to be transferred to the substrate comprises a region in which a basic pattern unit is repeated many times. For example, partial-block pattern transfer is generally used for patterns having large memory circuits, such as DRAMs. In such patterns, the basic pattern unit is very small, having measurements on the substrate of, for example, (10 μm) 2 (i.e., 10 μm×10 μm). The basic pattern unit is defined on one or several exposure units on the reticle and the exposure units are repeatedly exposed many times onto the substrate to form the pattern on the substrate. Unfortunately, partial-block pattern transfer tends to be employed only for repeated portions of the pattern. Portions of the pattern that are not repeated are transferred onto the substrate using a different method, such as the variable-shaped-beam method. Therefore, partial-block pattern-transfer has a throughput that is too low, especially for large-scale production of integrated circuits.
A conventional approach that has been investigated in an effort to achieve a higher throughput than partial-block pattern-transfer methods is a projection microlithography method in which the entire reticle pattern for a complete die (or even multiple dies) is projection-exposed onto the substrate in a single “shot.” In such a method, the reticle defines a complete pattern, such as for a particular layer in an entire integrated circuit. The image of the reticle pattern as formed on the substrate is “demagnified” by which is meant that the image is smaller than the pattern on the reticle by a “demagnification factor” (typically 4:1 or 5:1). To form the image on the substrate, a projection lens is situated between the reticle and the substrate. Whereas this approach offers prospects of excellent throughput, it to date has exhibited excessive aberrations and the like, especially of peripheral regions of the projected pattern. In addition, it is extremely difficult to manufacture a reticle defining an entire pattern that can be exposed in one shot.
Yet another approach that is receiving much current attention is the “divided” or “partitioned” projection-exposure approach that utilizes a “divided,” “partitioned,” or “segmented” reticle. On such a reticle, the overall reticle pattern is subdivided into portions termed herein “exposure units.” The exposure units can be of any of various types termed “subfields,” “stripes,” etc., as known in the art. Each exposure unit is individually and sequentially exposed in a separate “shot” or scan. The image of each exposure unit is projection-exposed (typically at a demagnification ratio such as 4:1 or 5:1) using a projection-optical system situated between the reticle and the substrate. Even though the projection-optical system typically has a large optical field, distortions, focal-point errors and other aberrations, and other faults in projected images of the exposure units are generally well controlled. Although divided projection-exposure systems provide lower throughput than systems that expose the entire reticle in one shot, divided projection-exposure systems exhibit better exposure accuracy and image resolution
In divided projection exposure, it is necessary to achieve very accurate alignment of the reticle with the substrate to ensure that the images of the exposure units are positioned at the respective locations on the reticle with extremely high accuracy. To such end, an operation termed “mark detection” is performed such as during calibration of the optical system and when aligning the substrate with the reticle before exposing an exposure unit onto the substrate. During mark detection, an image of one or more “upstream” marks provided on the reticle or other location on the reticle stage is projected onto a corresponding “downstream” mark provided on the substrate or other location on the substrate stage. The marks are scanned relative to each other to determine the relative positions of the marks.
Systems designed for high-resolution pattern transfer, such as the divided projection-exposure system summarized above, employ very large acceleration voltages such as between the CPB source and the reticle. To achieve the requisite high accuracy of mark detection, either mark scanning must be performed relatively slowly or a large number of scans must be performed. Consequently, the cumulative beam energy that strikes the marks and their immediate surrounding area is very high. This energy is usually dissipated as localized heating which elevates the temperature and causes thermal deformation of the vicinity of the marks. Such deformation degrades the accuracy with which mark positions can be determined, reduces calibration and alignment accuracy, and reduces the accuracy with which images of exposure units on the substrate can be stitched together. The resulting devices manufactured under such conditions exhibit a higher incidence of defects such as shorts, opens, and non-uniform resistance values.
SUMMARY OF THE INVENTION
The present invention solves certain of the problems of conventional apparatus and methods summarized above and thereby provide more accurate transfer of a reticle pattern to a substrate.
According to a first aspect of the invention, charged-particle-beam (CPB) microlithography (projection-exposure or projection-transfer) apparatus are provided. According to a representative embodiment, such an apparatus comprises an illumination optical system situated and configured to direct a charged-particle illumination beam along an optical axis from a source to a selected region on a reticle. The reticle is situated at a reticle plane orthogonal to the optical axis. The apparatus also comprises a projection-optical system situated and configured to direct a charged-particle imaging beam from the reticle to a sensitized substrate so as to transfer the pattern portion defined by the selected exposure unit to the substrate. An “upstream” mark is situated on the reticle plane so as to be selectively irradiated by the illumination beam. A shield is situated between the source and the upstream mark. The shield defines an aperture that transmits a portion of the illumination beam to the upstream mark while blocking other portions of the illumination beam from reaching the reticle plane.
In the embodiment summarized above, the upstream mark can be situated on the reticle. In such an instance, the reticle can comprise multiple upstream marks distributed over the reticle. In such a configuration, the shield desirably defines multiple apertures each corresponding to a respective individual upstream mark on the reticle.
Alternatively, the upstream mark can be situated on a mark member separate from the reticle, wherein the upstream mark is situated on the mark member. In such a configuration, the shield desirably extends over the mark member. This configuration is usually used for calibration of the optics of the CPB projection-exposure apparatus.
The upstream mark can comprise multiple mark portions. In such an instance, the aperture defined by the shield can be sized, whenever the aperture is axially registered with the upstream mark, to circumscribe all the mark portions collectively. Alternatively, the shield can define multiple apertures each corresponding to a respective individual mark portion.
According to another aspect of the invention, CPB microlithography methods are provided in which a charged-particle illumination beam is used to irradiate a portion of a pattern defined by a reticle situated on a reticle plane. A projection-optical system is used to direct a corresponding charged-particle imaging beam from the irradiated portion to a sensitized substrate situated on a substrate plane. An upstream mark is defined on the reticle plane and a “downstream” mark is defined on the substrate plane. The upstream mark is selectively registrable with the downstream mark to perform beam alignment. A shield is provided upstream of the upstream mark. The shield (a) serves to block downstream passage of the illumination beam, and (b) defines an aperture having a size and profile sufficient to pass therethrough only a portion of the illumination beam sufficient to irradiate the upstream mark. When irradiating the upstream mark with the illumination beam, the illumination beam is passed through the aperture of the shield before the illumination beam reaches the upstream mark. The upstream mark can be defined on the reticle, in which instance the shield desirably extends over the reticle. Alternatively, the upstream mark can be defined on a mark member (which can be separate from the reticle), in which instance the shield desirably extends over the mark member.
In conventional CPB projection-exposure systems having utility for, e.g., performing “divided” projection exposure, the illumination beam as incident on the reticle can have a transverse profile that is relatively large (e.g., (100 μm) 2 -(1000 μm) 2 ). A typical upstream mark is much smaller, on the order of a few μm square to about a hundred μm square. Whenever such upstream marks are illuminated by the charged particle beam during calibration or alignment, the beam that strikes the upstream mark is much larger in transverse area than required for illuminating the upstream mark. As summarized above, the resulting large amount of energy being dissipated in an area surrounding the upstream mark can cause thermal deformation of the upstream marks. Whereas it might be possible to reduce the transverse area of the beam, such a method is impractical because it requires a very complex irradiation optical system. Apparatus and methods according to the invention, as summarized above, reduce the transverse area of the illumination beam actually irradiating an upstream mark, thereby largely eliminating thermal deformation of the mark(s).
The foregoing and additional features and advantages of the invention will be more readily apparent from the following detailed description, which proceeds with reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an elevational section showing certain details of a reticle and reticle stage of a charged-particle-beam (CPB) projection-exposure system according to a first representative embodiment of the present invention.
FIGS. 2 (A)- 2 (D) are respective plan views depicting certain relationships between an upstream mark and an illumination beam, according to the first representative embodiment.
FIGS. 3 (A)-(B) are plan views of details of two respective example embodiments of a shield of a CPB projection-exposure system according to the invention.
FIG. 4 is an elevational section showing certain features of another representative embodiment in which the illumination beam passes through a lens from the shield to a mark member.
FIG. 5 is an elevational schematic drawing showing certain imaging relationships in an embodiment of an electron-beam projection-exposure system according to the invention.
DETAILED DESCRIPTION
Reference is first made to FIG. 5 which depicts a representative embodiment of a charged-particle-beam (CPB) projection-exposure apparatus that can include the instant invention. The FIG. 5 embodiment is discussed below in the context of an electron-beam system, but it will be understood that any of various other charged particle beams can be used with such an apparatus, such as an ion beam.
In FIG. 5, an electron gun 101 produces an electron beam EB that propagates in a downstream direction along an optical axis A. The electron beam EB propagates from the electron gun 101 through various components (discussed below) to a reticle 110 and then through other components (discussed below) to a substrate 114 .
Downstream of the electron gun 101 are situated a first condenser lens 103 and a second condenser lens 105 . The electron beam EB passes through the condenser lenses 103 , 105 and is converged at a crossover image C 01 . Downstream of the second condenser lens 105 is a beam-shaping aperture 106 . The beam-shaping aperture 106 trims the electron beam EB to have a transverse profile suitable for illuminating an individual exposure unit on the downstream reticle 110 .
Desirably, the beam-shaping aperture 106 trims the electron beam EB to have a transverse profile slightly larger than the area and profile of the exposure unit. For example, the beam-shaping aperture 106 can shape the electron beam to have a square profile measuring slightly more than one millimeter on a side as projected onto the reticle 110 , for illuminating an exposure unit measuring exactly 1 mm square.
A blanking aperture 107 is situated at the same axial position, downstream of the beam-shaping aperture 106 , as the crossover image C 01 . Immediately downstream of the blanking aperture 107 is a deflector 108 . A collimating lens 109 forms an image of the beam-shaping aperture 106 on the illuminated exposure unit on the reticle 110 .
As used herein, an “illumination beam” denotes the charged particle beam EB between the electron gun 101 and the reticle 110 , and an “imaging beam” denotes the charged particle beam between the reticle 110 and the substrate 114 . Similarly, the “illumination-optical system” denotes the optical system located between the source 101 and the reticle 110 , and the “projection-optical system” denotes the optical system located between the reticle 110 and the substrate 114 .
The deflector 108 sequentially scans the electron beam EB primarily in the X direction of FIG. 5 so as to illuminate, within the optical field of the illumination-optical system, a desired exposure unit on the reticle 110 .
With respect to the reticle 110 , although only one exposure unit (through which the optical axis A passes) is shown in FIG. 5, the reticle 110 actually extends outward in the X-Y plane (perpendicular to the optical axis) and typically comprises a large number of exposure units. As the exposure units are sequentially illuminated by the electron beam, the deflector 108 scans the electron beam, as discussed above, across the optical field of the illumination-optical system.
Provided downstream of the reticle 110 are first and second projection lenses 112 and 113 and a deflector 131 . The projection lenses are preferably configured as a “Symmetric Magnetic Doublet” or “SMD.” As each exposure unit on the reticle 110 is illuminated by the illumination beam, the beam passes through the illuminated exposure unit and thus acquires an ability to form an image of the illuminated exposure unit. The resulting imaging beam is demagnified by passage through the projection lenses 112 , 113 and deflected as required by the deflectors 131 to form an image of the illuminated exposure unit at the desired location on the substrate 114 .
The reticle 110 is mounted on a reticle stage 111 that is movable within an X-Y plane. In a similar manner, the substrate (e.g., a semiconductor wafer) 114 is mounted on a wafer stage 115 that is also movable within a respective X-Y plane. Hence, continuous scanning of the exposure units of the reticle pattern can be performed (assuming the projection lenses 112 , 113 are configured as an SMD) by scanning the reticle stage 111 and the wafer stage 115 in opposite directions along the Y axis. Both the reticle stage 111 and wafer stage 115 include highly accurate position-measurement systems employing laser interferometers as known in the art. The position-measurement systems, in concert with beam alignments and adjustments performed by the various deflectors of the illumination and projection optical systems, enable the images of the exposure units as formed on the substrate 114 to be accurately stitched together.
The upstream-facing surface of the substrate 114 is coated with a suitable resist so as to be imprintable with the projected image of the substrate pattern. To effect such imprinting, the substrate 114 must be exposed with a proper dosage of the imaging beam.
Situated upstream of the substrate 114 is a backscattered-electron detector 133 used for mark detection, as discussed below.
FIG. 1 shows the vicinity of a reticle stage according to a first representative embodiment of the invention. As shown in FIG. 1, a reticle 1 is mounted on a reticle stage 3 . A mark member 5 is situated adjacent the reticle on the reticle stage 3 . The upstream-facing surfaces of the mark member 5 and the reticle 1 are desirably co-planar in a “reticle plane” that is orthogonal to the optical axis. The mark member 5 desirably is made of silicon about 800 μm in thickness and defines one or more “upstream” marks, such as shown in FIGS. 2 (A)- 2 (D), useful for alignment and calibration purposes, for example. Whenever the charged particle beam 8 impinges on an upstream mark, some of the particles in the beam pass through the upstream mark and are projected onto a respective region on the substrate or wafer stage. The upstream-facing surface on the substrate or on the wafer stage where the upstream mark is projected desirably is situated in a “substrate plane” orthogonal to the optical axis.
Situated upstream of the mark member 5 is a shield 7 . The shield 7 desirably is made of an electrically conductive material such as tantalum or molybdenum having a thickness of approximately 0.1 to 1 mm in this embodiment. The shield 7 is supported relative to the reticle stage 3 by a leg portion 7 b from which a shield plate 7 c extends in a cantilever manner so as to cover the mark member 5 . The gap between the mark member 5 and the shield 7 is desirably within the range of approximately 0.1 mm to several mm. Alternatively, a separate leg portion 7 b can be placed along each of at least two edges of the shield plate 7 c , or the shield plate can be supported relative to the reticle stage 3 in any of various other suitable ways. Flanking the shield 7 b is a laser mirror 9 used by the position-measurement system of the reticle stage discussed above.
The shield plate 7 c defines an aperture 7 a that is desirably slightly larger than the upstream mark on the mark member 5 . The aperture 7 a desirably is located in the center of the shield plate 7 c and axially registered with the upstream mark on the mark member 5 . The aperture 7 a is discussed further below, with reference to FIGS. 3 (A) and 3 (B).
The reticle 1 also can be covered with a shield 6 that defines apertures 6 a in locations on the shield 6 that correspond to the locations of corresponding upstream marks on the reticle 1 .
Representative relationships between an upstream mark and the illumination beam are depicted in FIGS. 2 (A)- 2 (D). FIG. 2 (A) shows the area encompassed by a single exposure unit 11 , with the superposed transverse profile of the illumination beam 13 . (The exposure-unit area 11 encompasses that portion of the overall reticle pattern transferred from the reticle 1 to the substrate in a given instant of time.) For divided projection exposure, a typical exposure-unit area 11 would be square or rectangular in profile and have an area (on the reticle) of approximately (100 μm) 2 to (1000 μm) 2 . With a demagnification ratio of 4:1, for example, such an exposure unit would illuminate an area of approximately (25 μm) 2 to (250 μm) 2 respectively, on the substrate. For a shaped-beam single-shot transfer technique such as cell projection, the typical exposure-unit area 11 would measure (100 μm) 2 to (200 μm) 2 on the reticle. With a demagnification ratio of 25:1, for example, such an exposure unit would illuminate an area of about (5 μm) 2 on the substrate. In FIGS. 2 (A)- 2 (D), the upstream marks are formed on the same membrane region of the reticle as the pattern to be projection-transferred to the substrate.
The transverse area of the illumination beam 13 is slightly larger than the exposure unit 11 . For example, if the exposure unit 11 were a square measuring 1000 μm×1000 μm, then the transverse area of the illumination beam 13 would be a square measuring about 1000 μm×1000 μm.
FIG. 2 (B) shows a relatively large (relative to the aperture 21 ) upstream mark 23 that has especial utility for aligning and calibrating the main field of the illumination and imaging optical systems. The mark is configured as a line-and-space pattern in which each line has a width of, by way of example, 1.6 μm, a length of 50 μm and spacing therebetween of 3.2 μm. The illumination beam illuminates the upstream mark 23 . As the illumination beam illuminates the mark 23 , the portion of the beam passing through the mark is projected onto the substrate (or other suitable location on the substrate plane). The projection is performed such that the projected image of the upstream mark 23 overlays a corresponding “downstream” mark on the substrate (or substrate plane). The image of the upstream mark 23 is scanned onto the downstream mark by the deflector 131 (FIG. 5 ). The backscattered-electron detector 133 (FIG. 5) detects backscattered electrons propagating from the overlaying marks. Based on the resulting detection signal relative to the scan signal, a measurement is performed in which a mark pattern previously imprinted on the substrate or substrate plane is aligned so as to be in registration with the newly projected mark pattern. Alternatively, a calibration can be performed in which one or more of demagnification ratio, rotation, distortion, lateral position, and focus position, for example, is adjusted as required.
FIG. 2 (C) shows a relatively small (relative to the aperture 31 ) upstream mark 33 that has especial utility for calibrations and corrections of distortion of exposure units as projected onto the substrate. The upstream mark 33 is further detailed in the enlargement shown in FIG. 2 (D), in which the mark comprises multiple lines 35 each having, by way of example, a width of several μm, a length of about 10 μm, and spaces therebetween each having a width of 2 μm.
The mark patterns shown in FIGS. 2 (B) and 2 (C) are significantly smaller than the transverse profile of the illumination beam 13 . As a result, many (if not most) of the charged particles in the illumination beam are not used to illuminate the marks per se but rather used to illuminate the vicinity of the marks. I.e., most of the charged particles impinge on the mark member 5 (or the reticle if the upstream marks are defined on the reticle) and cause localized heating and consequent thermal deformation of the mark member (or reticle). Such thermal deformation causes the shapes and positions of the upstream marks (and of the lines or elements thereof) to change. Such changes degrade alignment and calibration accuracy, which degrade the accuracy with which the reticle pattern can be transferred to the substrate. The shields 6 , 7 shown in FIG. 1 alleviate this problem.
Details of a shield 6 , 7 according to two example embodiments are shown in FIGS. 3 (A) and 3 (B), respectively. Turning first to FIG. 3 (A) the shield 6 , 7 is shown in plan view. The perimeter of the shield 6 , 7 encloses an area that is larger than the transverse area and profile of the illumination beam 13 . For example, if the illumination beam 13 has a 1100 μm×1100 μm transverse profile, then the shield 6 , 7 has at least a slightly larger area. The center of the shield 6 , 7 defines an aperture 6 a , 7 a measuring, by way of example, 55 μm×55 μm. The aperture 6 a , 7 a is situated such that the upstream mark 23 (which, by way of example occupies an area of approximately 50 μm×50 μm) when viewed axially is approximately centered in the aperture 6 a , 7 a . To illuminate the upstream mark 23 , the illumination beam first passes through the aperture 6 a , 7 a ; the shield 6 , 7 blocks most of the illumination beam from reaching anything downstream other than the upstream mark 23 . As a result, only that portion of the illumination beam that is actually required to illuminate the upstream mark 23 strikes the mark member 5 . The amount of heating imparted to the mark member 5 is thus much less than if the shield 6 , 7 were absent.
The example embodiment of the shield shown in FIG. 3 (B) is especially useful whenever the space between the lines of the upstream mark 23 is relatively wide. Rather than having a single large aperture 6 a , 7 a , as used in the FIG. 3 (A) embodiment, the shield 6 ′, 7 ′ in the FIG. 3 (B) embodiment defines individual slit-shaped apertures 6 a ′, 7 a ′ for each respective line of the mark 23 . By way of example, each slit-shaped aperture 6 a ′, 7 a ′ has a width of 5.5 μm and a length of 51 μm. Thus, each slit-shaped aperture 6 a ′, 7 a ′ is slightly larger than the corresponding line of the mark 23 . The FIG. 3 (B) configuration further reduces the electron dose received by regions of the mark member 5 (or reticle) outside the upstream mark 23 . This, in turn, further reduces thermal deformation of the mark member (or reticle).
Turning now to FIG. 4 showing another representative embodiment, a shield 51 defining an aperture 51 a is axially separated from a mark member 57 . I.e., the shield 51 is situated upstream of the mark member 57 , and a lens 53 is situated between the shield and the mark member. An illumination beam 55 , having passed through the aperture 51 a in the shield 51 is projected by the lens 53 onto (and imaged on) an upstream mark 57 a on the mark member 57 . In this configuration, the upstream mark 57 a on the mark member (or reticle) is selectively illuminated by the illumination beam. This avoids thermal deformation of the mark member (or reticle) due to excessive localized irradiation by the illumination beam.
Therefore, the present invention provides a shield situated over a location on a reticle plane (e.g., a mark member or reticle) defining an upstream mark. The shield effects more localized irradiation of the upstream mark during instances in which the upstream mark is being irradiated by the illumination beam. Consequently, excess irradiation of the vicinity of the upstream mark is prevented, which correspondingly reduces thermal deformation of the mark and increases the accuracy of mark detection.
Whereas the invention has been described in connection with multiple representative embodiments, it will be apparent that the invention is not limited to those embodiments. On the contrary, the invention is intended to encompass all alternatives, modifications, and equivalents as may be encompassed within the spirit and scope of the invention as defined by the appended claims. | Methods and apparatus are disclosed for reducing thermal deformation of “upstream” marks (as used for alignment and/or calibration) situated on a reticle or on a reticle plane (e.g., on the reticle stage), thereby facilitating more accurate transfer of the reticle pattern to a sensitized substrate (e.g., semiconductor wafer) using a charged particle beam (e.g., electron beam). The charged particle beam illuminates an upstream mark situated on the reticle or on a reticle plane and projects an image of the illuminated upstream mark onto a corresponding “downstream” mark situated on a substrate plane. A shield is situated upstream of the upstream mark and serves to block downstream passage of the charged particle beam except to illuminate the upstream mark or a portion of the upstream mark. The upstream mark can be situated on the reticle or on a mark member situated in the reticle plane. | 7 |
CROSS REFERENCE TO RELATED APPLICATIONS
This application is a continuation-in-part of Ser. No. 094,636, filed Sept. 9, 1987, now U.S. Pat. No. 4,864,028, issued Sept. 5, 1989, which is a continuation-in-part of Ser. No. 005,859, filed Jan. 21, 1987 (now abandoned), which is a continuation of Ser. No. 766,569, filed Aug. 14, 1985 (now abandoned), which is a continuation of Ser. No. 532,168, filed Sept. 14, 1983, now U.S. Pat. No. 4,537,892.
FIELD OF THE INVENTION
This invention relates to novel spiro-tricyclicaromatic succinimide derivatives and related spiro-heterocyclic analogs such as spiro-tricyclicaromatic-thiazolidine-dione, -imidazolidienedione, and -oxazolidine-dione derivatives. More particularly, the invention relates to spiro-tricyclicaromatic succinimide derivatives and related spiro-heterocyclic analogs which are useful to prevent diabetic cataract, nerve tissue damage, and certain vascular changes.
BACKGROUND ART
As disclosed in U.S. Pat. No. 3,821,383, aldose reductase inhibitors such as 1,3-dioxo-1H-benz [d,e]-isoquinoline-2(3H)-acetic acid, and its derivatives, are useful as inhibitors of aldose reductase and alleviators of diabetes mellitus complications. Spiro-[chroman-4,4'-imidazolidine]-2',5'-dione and spiro-[imidazolidine-4,4'-thiochroman]-2,5-dione and their derivatives, disclosed in U.S. Pat. Nos. 4,130,714 and 4,209,630, are also indicated as being useful in this regard. Certain spiro-polycyclicimidazolidinedione derivatives from U.S. Pat. No. 4,181,728 have been demonstrated to have inhibitory activity against aldose reductase and polyol accumulation. U.S. Pat. No. 4,117,230 describes a series of spiro-hydantoin compounds which include the 6-fluoro and 6,8-dichloro derivatives of spiro-chroman imidazolidmediones. Spiro-fluorenhydantoin and its derivatives are disclosed in my prior U.S. Pat. Nos. 4,438,272 and 4,436,745, as being potent human and rate aldose reductase inhibitors which prevent polyol accumulation in lenticular and nervous tissues of diabetic and galactosemic rats and prevent cataract and nerve dysfunction in diabetic rats. Pan et al, J. Med. Chem. 7, 31-38 (1964), describes halogenofluorenes as potential antitumor agents, and Pan et al, J. Med. Chem. 10, 957-959 (1967), describes spiro[fluoren-9,4'-imidazolidine]-2',5'-diones as potential antitumor agents.
SUMMARY OF THE INVENTION
It is one object of the invention to provide a novel series of spiro-tricyclicaromatic succinimide derivatives and related spiro-heterocyclic analogs, and methods for their preparation, which compounds are useful as inhibitors of aldose reductase and alleviators of diabetes mellitus complications.
A still further object of the invention is to provide pharmaceutical compositions and methods for inhibiting aldoreductase and the treatment of diabetes mellitus wherein the active ingredient comprises a spiro-tricyclicaromatic succinimide derivative or spiro-heterocyclic analog.
Other objects and advantages of the present invention will become apparent as the description thereof proceeds.
In satisfaction of the foregoing objects of the invention, there is provided by the broadcast embodiment of the invention, substituted or unsubstituted planar tricyclic fluorene or nuclear analogs thereof, spiro-coupled to a five-membered ring containing a secondary amide, and the pharmaceutically acceptable salts thereof.
In further satisfaction of the foregoing objects and advantages, there are provided by the present invention spiro-tricyclic-aromatic imides of the formula: ##STR1## and the pharmaceutically acceptable metal salts and in cases, where the basic aromatic nitrogens are in the A, and/or B ring, the pharmaceutically acceptable organic and inorganic salts thereof, wherein A and B are aromatic or heterocyclic rings connected through two adjacent positions to a central five-membered ring, the A and B rings being selected from the group consisting of those of the formula: ##STR2## and wherein U is selected from the group consisting of O, S, N--R 1 ;
X is selected from the group consisting of H, F, lower alkyl sulfide (e.g., --S--CH 3 ), lower alkylsulfinyl (e.g., --S(O)CH 3 );
Y is selected from the group consisting of H, --OH, and ##STR3## F, Cl, lower alkyl, lower alkoxy, lower alkylsulfide (e.g., --S--CH 3 ), lower alkylsulfinyl (e.g., --S(O)--CH 3 ), lower alkylsulfonyl (e.g., --SO 2 CH 3 ), --CF 3 , --S--CF 3 , --SO 2 CF 3 , CO--N(R 1 )--R 2 , lower alkyl alcohol (e.g., --CH 2 --OH), lower alkyl ether (e.g., --CH 2 OCH 3 ), nitro, lower alkyl sulfide lower alkyl (e.g., --CH 2 S-CH 3 ), lower alkylamine (e.g., --CH 2 NH 2 ), lower alkyl esters (e.g., --CH 2 --O--COCH 3 ), carboxylic acids and lower alkyl esters (e.g., --COOR 3 ), lower alkyl carboxylic acids and esters (e.g., --CH(CH 3 )--COOR 1 ), lower cycloalkyl (e.g., cyclopropyl); provided that when both of Rings A and B are phenyl, and one of X or Y is H or F, the other of X or Y must be other than H or F;
R 1 and R 2 are selected from the group consisting of H and lower alkyl (preferably methyl or ethyl);
R 3 is lower alkyl (preferably methyl or ethyl);
Z is selected from the group consisting of H, lower alkyl (preferably methyl), and halogen (fluoro, chloro, bromo, iodo); and
t is selected from the group consisting of NH, O, S, and CHR 1 . Lower alkyl is defined as containing six or less carbon atoms.
Also provided are methods for preparation of the above described compounds, pharmaceutical compositions containing these compounds as the active ingredient, and methods for treatment of diabetic cataract, nerve tissue damage, and certain vascular changes utilizing the above described compounds as the active ingredient.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The present invention is concerned with novel spiro-tricyclicaromatic succinimide derivatives and relates spiro-heterocyclic analogs such as spiro-tricyclicaromatic-thiazolidinedione, -imidazolidinedione, and -oxazolidinedione derivatives. The invention is also concerned with methods for preparation of these compounds, and methods for treatment of diabetic cataract, nerve tissue damage, and certain vascular changes using pharmaceutical compositions containing the compounds of the present invention as the active ingredient.
The compounds of the present invention are inhibitors of the enzyme aldose reductase and, while applicant is not bound by any theory, the pharmaceutical utility of the compounds of the present invention appears to correlate with their observed aldoreductase inhibitory property. The inhibition of the enzyme aldose reductase and related reductases results in the inhibition of abnormal polyol accumulation at the expense of NADPH in those tissues containing aldose reductase and/or related aldehyde reductases. The inhibition of the formation of a polyol, such as sorbitol or galactitol, arising from the reduction of an aldose, such as glucose or galactose respectively, is believes beneficial to delay the progression of certain complications arising from hyperglycemia or hypergalactocemia. Hyperglycemia is associated with the complications of neuropathy, retinopathy, cataract, glaucoma, and impaired wound healing in diabetes mellitus patients.
According to U.S. Pat. No. 3,821,383, aldose reductase inhibitors such as 1,3-dioxo-1H-benz[d,e]-isoquinoline-2-(3H)-acetic and its derivatives are useful as inhibitors of aldose reductase and alleviators of diabetis mellitus complications. Spiro-[chroman-4,4'-imidazolidine]-2',5'-dione and spiro-[imidazolidine-4,4'-thichroman]-2,5-dione and their derivatives from U.S. Pat. Nos. 4,130,714 and 4,209,630 have also proven useful in this regard. Certain spiro-polycyclicmidazolidinedione derivatives from U.S. Pat. No. 4,181,728 have been demonstrated to have inhibitory activity against aldose reductase and polyol accumulation. Spiro-fluorenhydantoin and its derivatives, according to the above-mentioned U.S. Pat. Nos. 4,438,272 and 4,436,745, are potent human and rat aldose reductase inhibitors which prevent polyol accumulation in lenticular and nervous tissues of diabetic and galactosemic rats and prevent cataract and nerve dysfunction in diabetic rates. Such compounds inhibit the reduction of aldoses such as glucose and galactose to sorbitol and galactitol, thus preventing the harmful accumulation of polyols in certain nervous, ocular, and vascular tissues. Effective aldose reductase inhibitor chemotherapy prevents, improves, or delays the onset, duration or expression of certain sequelae of diabetes mellitus which include ocular sequelae (e.g., cataract and retinopathy), kidney damage (nephropathy), neurological dysfunction (e.g., peripheral sensory neuropathy), vascular disease (e.g., diabetic micro- and macro-vasculopathies), impaired wound healing (e.g., impaired corneal reepithelialization) and heart disease. The discussion of the aldose reductase utility as described in U.S. Pat. No. 4,209,630 is hereby incorporated herein by reference.
As a result, the compounds of the present invention are of significant value as aldose reductase inhibitors, since it is already known in the art that aldose reductase inhibitors prevent diabetic cataract, nerve tissue damage, and certain vascular changes.
In accordance with the present invention, it has been surprisingly found that various spirocyclic imide containing derivatives of the tricycle fluorene and related heterocyclic analogs of fluorene and their derivatives are extremely useful as inhibitors of aldose reductase, especially human aldose reductase.
The spiro-cyclic aromatic imides of the present invention may be described by the following general formula: ##STR4## and the pharmaceutically acceptable metal salts and in cases, where basic aromatic nitrogens are in the A, and/or B rings, the pharmaceutically acceptable organic and inorganic acid salts thereof, wherein A and B are aromatic or heterocyclic rings connected through two adjacent positions to a central cycloalkyl ring, the A and B rings being selected from the group consisting of those of the formula: ##STR5## and wherein U is selected from the group consisting of O, S, N--R 1 ;
X is selected from the group consisting of H, F, lower alkyl sulfide (e.g., --S--CH 3 ), lower alkylsulfinyl (e.g., --S(O)CH 3 ); ##STR6## F, Cl, lower alkyl, lower alkoxy, lower alkylsulfide (e.g., --S--CH 3 ), lower alkylsulfinyl (e.g., --S(O)--CH 3 ), lower alkylsulfonyl (e.g., --SO 2 CH 3 ), --CF 3 , --S--CF 3 , --SO 2 CF 3 , CO--N(R 1 )--R 2 , lower alkyl alcohol (e.g., --CH 2 -OH), lower alkyl ether (e.g., --CH 2 OCH 3 ), nitro, lower alkyl sulfide lower alkyl (e.g., --CH 2 S--CH 3 ), lower alkylamine (e.g., --CH 2 NH 2 ), lower alkyl esters (e.g., --CH 2 --O--COCH 3 ), carboxylic acids and lower alkyl esters (e.g., --COOR 3 ), lower alkyl carboxylic acids and esters (e.g., --CH(CH 3 )--COOR 1 ), lower cycloalkyl (e.g., cyclopropyl); provided that when both of Rings A and B are phenyl, and one of X or Y is H or F, the other of X or Y must be other than H or F;
R 1 and R 2 are selected from the group consisting of H and lower alkyl (preferably methyl or ethyl);
R 3 is lower alkyl (preferably methyl or ethyl);
Z is selected from the group consisting of H, lower alkyl (preferably methyl), and halogen (fluoro, chloro, bromo, iodo); and
t is selected from the group consisting of NH, O, S, and CHR 1 .
In a more preferred embodiment, the spiro-cyclic aromatic imides of the present invention are of the following general formula: ##STR7## wherein A, B, U, X, Y, R 1 , R 2 , R 3 , Z, and t are as described above. In more preferred embodiments, the cycloalkyl groups have 4 to 7 carbon atoms and lower alkyl groups have 1 to 6 carbon atoms. In an especially preferred embodiment, Ring A is selected from the foregoing group and Ring B is selected from the group consisting of the following: ##STR8## where X, U, and Z are described above. In the compounds of Formulae I and I-A, Rings A and B are attached to the central five-membered ring at positions 1,2 and 3,4.
The compounds of the present invention have important geometric and chemical similarities. These similarities include a planar rigid tricyclic fluorene or fluorene-like aromatic ring system spiro-coupled to a five-membered imide (or cyclic secondary amide) ring such as succinimide, hydantoin, thiazolidinedione or oxazolidinedione. These spirocyclic derivatives of the various tricycles each contain a polarizable and hydrogen-bondable secondary amide, also called imide, radical (--CO--NH--CO--).
In those instances where, according to general Formulae I and I-A, A does not equal B, the spiro carbon is chiral. Activity of any such racemic mixture maybe attributable to only one isomer. Resolution, or direct synthesis, of the enantiomers, as is known in the art, is recognized as a method to isolate or prepare the active or the more active enantiomer. It is also recognized that certain patterns of substitution on A and/or B according to Formulae I and I-A may create asymmetry, and the resulting diastereomeric mixtures may be separated by chromatography or solvent recrystallizations, as is known and practiced in the art. For example, if A has a methylsulfoxyl substituent and A is different from B, then there are at least two chiral centers: the spiro carbon and the sulfoxide sulfur. Physical separation of this diastereomeric mixture by chromatography or other methods practiced in the art will yield two racemic mixtures, each containing a pair of enantiomers. Stereospecific oxidation of a methylsulfide on A to yield a methylsulfoxide (e.g., via sodium metaperiodate and albumin) when A is different than B (according to Formula I) will yield a diastereomeric mixture, which then can be separated by conventional physical methods known in the art, such as liquid chromatography or differential solvent solubility, to yield the purified diastereomers which are themselves purified optical isomers. Reduction of the two optically active sulfoxide diastereomers will yield the optically active pair of enantiomers or mirror image isomers.
Of special interest in this invention are typical and preferred specie of Formula I such as those racemic mixtures: spiro-(6-fluoro-4H-indeno[1,2-b]thiopen-4,4'-imidiazolidine)-2',5'-dione; spiro-(7-fluoro-9H-pyrrolo[1,2-a]indol-9,4'-imidazolidine)-2',4'-dione; spiro-(2-fluoro-9H-fluoren-9,4'-imidazolidine)-2',5'-dione; spiro-(6-fluoro-8H-indeno[2,1-b]thiophen-8,4'-imidazolidine)-2',5'-dione; spiro-(2-fluoro-9H-fluoren-9,3'-succinimide); spiro-(2-fluoro-9H-fluoren-9,5'-thiazolidine)-2',4'-dione; spiro-(7-fluoro-9H-indeno[2,1-c]pyridin-9,4'-imidazolidine)-2',5'-dione; spiro-(7-fluoro-5H-indeno[1,2-b]pyridin-5,4'-imidazolidine)-2',5'-dione; spiro-(7-fluoro-5H-indeno[1,2-c]pyridin-5,4'-imidazolidine)-2',5'-dione; spiro-(7-fluoro-9H-indeno[2,1-b]pyridin-5,4'-imidazolidine)-2',5'-dione; spiro-(7-fluoro-5H-indeno[1,2-c]pyridin-5,5'-thiazolidine)-2',4'-dione; spiro-(7-fluoro-5H-indeno[1,2-b] pyridin-5,5'-thiazolidine)-2',4'-dione; spiro-(7-fluuoro-9H-indeno[2,1-c]pyridin-9,5'-thiazolidine)-2',4'-dione; spiro-(7-fluoro-9H-[2,1-b]pyridine-9,5'-thiazolidine)-2',4'-dione; spiro-(7-fluoro-5H-indeno[1,2-b]pyridine-5,3'-succinimide; spiro-(7-chloro-5H-[1,2-b]pyridin-5,5'-thiazolidine)-2',4'-dione; spiro-(7-chloro-5H-[1,2-b]pyridin-5,5'-oxazolidine)-2',4'-dione; spiro-(6-fluoro-4H-indeno[1,2-b]thiophen-4,5'-thiazolidine)-2',4'-dione; spiro-(6-chloro-8H-indeno[2,1-b]thiophen-8,5'-thiazolidine)-2',4'-dione; spiro-(2-fluoro,7-methylthiol-9H-fluoren-9-,5'-thiazolidine)-2',4'-dione.
The compounds of Formula I identified below by means of both linear nomenclature and structural formulas are also of special interest:
__________________________________________________________________________COM-POUNDNAME__________________________________________________________________________1 2-METHYL-7-FLUOROSPIRO[5 .sub.-- H-INDENO[1,2-b]PYRIDIN-5,4'-IMIDAZOLIDINE]-2',5'-DIONE2 2-METHYL-7-FLUOROSPIRO[5 .sub.-- H-INDENO[1,2-b]PYRIDIN-5,5'-OXAZOLIDINE]-2',4'-DIONE3 2,7-DIFLUORO-4-METHYLSPIRO[9 .sub.-- H-FLUORENE-9,3'-PYRROLIDINE]-2',5'-DIONE (IC50 = 2.8 × 10.sup.-9 --M)*4 7,9-DIFLUORO-4-METHYLSPIRO[5 .sub.-- H-INDENO[1,2-b]PYRIDIN-5,3'-PYRROLIDINE]-2',5'-DIONE5 2,7-DIFLUORO-4-METHYLSPIRO[9 .sub.-- H-FLUORENE-9,5'-THIAZOLIDINE]-2',4'-DIONE6 2,4,5,7-TETRAFLUOROSPIRO[9 .sub.-- H-FLUORENE-9,3'-PYRROLIDINE]-2',5'-DIONE7 2,4,5,7-TETRAFLUOROSPIRO[9 .sub.-- H-FLUORENE-9,5'-THIAZOLIDINE]-2',4'-DIONE (IC50 = 1.7 × 10.sup.-8 --M)*8 2,4,5,7-TETRAFLUOROSPIRO[9 .sub.-- H-FLUORENE-9,5'-OXAZOLIDINE]-2',4'-DIONE9 2,4,5,7-TETRAFLUOROSPIRO[9 .sub.-- H-FLUORENE-9,4'-IMIDAZOLIDINE]-2',5'-DIONE (IC50 = 1.2 × 10.sup.-8 --M)*10 2,7-DIFLUORO-4-METHYLSPIRO[9 .sub.-- H-FLUORENE-9,5'-OXAZOLIDINE]-2',4'-DIONE11 2,7-DIFLUORO-4-METHYLSPIRO[9 .sub.-- H-FLUORENE-9,4'-IMIDAZOLIDINE]-2' ,5'-DIONE (IC50 = 1.28 × 10.sup.-8 --M)*12 7,9-DIFLUOROSPIRO[5 .sub.-- H-INDENO[1,2-c]PYRIDIN-5,3'-PYRROLIDINE]-2',5'-DIONE13 7,9-DIFLUOROSPIRO[5 .sub.-- H-INDENO[1,2-c]PYRIDIN-5,4'-IMIDAZOLIDINE]-2',5'-DIONE14 7,9-DIFLUOROSPIRO[5 .sub.-- H-INDENO[1,2-c]PYRIDIN-5,5'-OXAZOLIDINE]-2',4'-DIONE15 2,7-DIFLUORO-4-METHOXYSPIRO[9 .sub.-- H-FLUORENE-9,5'-OXAZOLIDINE]-2',4'-DIONE16 2,7-DIFLUORO-4-METHOXYSPIRO[9 .sub.-- H-FLUORENE-9,4'-IMIDAZOLIDINE]-2',5'-DIONE (IC50 = 9.4 × 10.sup.-9 --M)*17 2,7-DIFLUORO-4-METHOXYSPIRO[9 .sub.-- H-FLUORENE-9,3'-PYRROLIDINE]-2',5'-DIONE (IC50 = 4.8 × 10.sup.-9 --M)*18 2,7-DIFLUORO-4-METHOXYSPIRO[9 .sub.-- H-FLUORENE-9,5'-THIAZOLIDINE]-2'-4'-DIONE19 2,4,7-TRIFLUORO-5-METHYLSPIRO[9 .sub.-- H-FLUORENE-9,5'-THIAZOLIDINE]-2'-4'-DIONE20 7,9-DIFLUORO-2-METHYLSPIRO[5 .sub.-- H-INDENO[1,2-b]PYRIDIN-5,5'-OXAZOLIDINE]-2',4'-DIONE21 7,9-DIFLUORO-2-METHYLSPIRO[5 .sub.-- H-INDENO[1,2-b]PYRIDIN-5,3'-PYRROLIDINE]-2',5'-DIONE22 7,9-DIFLUORO-2-METHYLSPIRO[5 .sub.-- H-INDENO[1,2-b]PYRIDIN-5,4'-IMIDAZOLIDINE]-2',5'-DIONE(IC50 = 4.8 × 10.sup.-8 --M)*23 2,4,7-TRIFLUORO-5-METHYLSPIRO[9 .sub.-- H-FLUORENE-9,3'-PYRROLIDINE]-2',5'-DIONE24 2,4,7-TRIFLUORO-5-METHYLSPIRO[9 .sub.-- H-FLUORENE-9,5'-OXAZOLIDINE]-2',4'-DIONE25 2,4,7-TRIFLUORO-5-METHYLSPIRO[9 .sub.-- H-FLUORENE-9,4'-IMIDAZOLIDINE]-2',5'-DIONE26 2,4,7-TRIFLUORO-5-METHOXYSPIRO[9 .sub.-- H-FLUORENE-9,5'-THIAZOLIDINE]-2',4'-DIONE27 2,4,7-TRIFLUORO-5-METHOXYSPIRO[9 .sub.-- H-FLUORENE-9,3'-PYRROLIDINE]-2',5'-DIONE28 2,4,7-TRIFLUORO-5-METHOXYSPIRO[9 .sub.-- H-FLUORENE-9,4'-IMIDAZOLIDINE]-2',5'-DIONE (IC50 = 1.13 × 10.sup.-5 --M)*29 2,4,7-TRIFLUORO-5-METHOXYSPIRO[9 .sub.-- H-FLUORENE-9,5'-THIAZOLIDINE]-2',4'-DIONE30 2,4,7-TRIFLUORO-5-METHYLTHIOSPIRO[9 .sub.-- H-FLUORENE-9,3'-PYRROLIDINE]-2',5'-DIONE31 2,4,7-TRIFLUORO-5-METHYLTHIOSPIRO[9 .sub.-- H-FLUORENE-9,4'-IMIDAZOLIDINE]-2',5'-DIONE32 2,7-DIFLUORO-4-METHYLSULFINYLSPIRO[9 .sub.-- H-FLUORENE-9,5'-OXAZOLIDINE]-2',4'-DIONE33 2,4,7-TRIFLUORO-5-METHYLTHIOSPIRO[9 .sub.-- H-FLUORENE-9,5'-OXAZOLIDINE]-2',4'-DIONE34 2,7-DIFLUORO-4-METHYLTHIOSPIRO[9 .sub.-- H-FLUORENE-9,4'-IMIDAZOLIDINE]-2',5'-DIONE (IC50 = 1.75 × 10.sup.-8 --M)*35 2,7-DIFLUORO-4-METHYLSULFINYLSPIRO[ 9 .sub.-- H-FLUORENE-9,4'-IMIDAZOLIDINE]-2',5'-DIONE36 2,7-DIFLUORO-4-METHYLTHIOSPIRO[9 .sub.-- H-FLUORENE-9,5'-OXAZOLIDINE]-2',4'-DIONE37 2,7-DIFLUORO-4-METHYLSULFINYLSPIRO[9 .sub.-- H-FLUORENE-9,3'-PYRROLIDINE]-2',5'-DIONE38 2,7-DIFLUORO-4-METHYLTHIOSPIRO[9 .sub.-- H-FLUORENE-9,3'-PYRROLIDINE]-2',5'-DIONE39 3,7-DIFLUORO-9-METHYLSPIRO[5 .sub.-- H-INDENO[1,2-b]PYRIDIN-5,5'-THIAZOLIDINE]-2',4'-DIONE40 3,7-DIFLUORO-9-METHYLTHIOSPIRO[5 .sub.-- H-INDENO[1,2-b]PYRIDIN-5,5'-THIAZOLIDINE]-2',4'-DIONE41 3,7-DIFLUORO-9-METHYLSPIRO[5 .sub.-- H-INDENO[1,2-b]PYRIDIN-5,3'-PYRROLIDINE]-2',5'-DIONE42 7-FLUORO-5-METHYLTHIOSPIRO[9 .sub.-- H-PYRROLO[1,2-a]INDOL-9,4'-IMIDAZOLIDINE]-2',5'-DIONE43 3,7-DIFLUORO-9-METHYLSPIRO[5 .sub.-- H-INDENO[1,2-b]PYRIDIN-5,4'-IMIDAZOLIDINE]-2',5'-DIONE(IC50 = 1.61 × 10.sup.-8 --M)*44 3,7-DIFLUORO-9-METHYLTHIOSPIRO[5 .sub.-- H-INDENO[1,2-b]PYRIDIN-5,3'-PYRROLIDINE]-2',5'-DIONE45 3,7-DIFLUORO-9-METHYLSPIRO[5 .sub.-- H-INDENO[1,2-b]PYRIDIN-5,5'-OXAZOLIDINE]-2',4'-DIONE46 3,7-DIFLUORO-9-METHYLTHIOSPIRO[5 .sub.-- H-INDENO[1,2-b]PYRIDIN-5,5'-OXAZOLIDINE]-2',4'-DIONE47 3,7-DIFLUORO-9-METHYLTHIOSPIRO[5 .sub.-- H-INDENO[1,2-b]PYRIDIN-5,4'-IMIDAZOLIDINE]-2',5'-DIONE48 3,7-DIFLUORO-2-METHYLTHIOSPIRO[9 .sub.-- H-PYRROLO[1,2-a]INDOL-9,4'-IMIDAZOLIDINE]-2',5'-DIONE49 5,7-DIFLUORO-3-METHYLSPIRO[9 .sub.-- H-PYRROLO[1,2-a]INDOL-9,4'-IMIDAZOLIDINE]-2',5'-DIONE50 7-FLUORO-5-METHOXYSPIRO[9 .sub.-- H-PYRROLO[1,2-a]INDOL-9,4'-IMIDAZOLIDINE]-2',5'-DIONE51 5,7-DIFLUORO-2-METHYLSULFINYLSPIRO[9 .sub.-- H-PYRROLO[1,2-a]INDOL-9,4'-IMIDAZOLIDINE]-2',5'-DIONE52 7-FLUORO-5-METHYLSPIRO[9 .sub.-- H-PYRROLO[1,2-a]INDOL-9,4'-IMIDAZOLIDINE]-2',5'-DIONE__________________________________________________________________________ *IC50 values are based on inhibition of rat lens aldose reductase. ##STR9##
Also of special interest in this invention are these achiral or nonracemic compounds: spiro-(2,7-difluoro-9H-fluoren-9,4'-imidazolidine)-2',5'-dione; spiro-(2,7-difluoro-9H-fluoren-9,5'-thiazolidine)-2',4'-dione; spiro-(2,7-difluoro-9H-fluoren-9, 3'-succinimide); spiro-(2,7-difluoro-9H-fluoren-9,5'-oxazolidine)-2',4'-dione. All the aforementioned compounds are highly potent as regards their aldose reductase inhibitory activities. All of the aforementioned preferred compounds as in Formula I may be formulated as the base salts thereof with pharmacologically acceptable cations (e.g., sodium salt). Alternatively, several preferred examples such as spiro-(7-fluoro-5H-indeno[1,2-b]pyridin-5,5'-thiazolidine)-2',4'-dione and related examples which contain a basic nitrogen in ring(s) A and/or B according to Formula I can be formulated as the acid salt with pharmacologically acceptable strong acids (e.g., hydrochloride salt).
The novel compounds of the present invention are readily prepared from appropriate ketones of Formula II of their methylene analogs of Formula III: ##STR10## wherein A and B are previously defined with the exception that introduction of a nitro substituent(s) is conducted after hydantoin derivatization. Similarly, certain other derivatizations, e.g., esterifications of carboxylic acids, oxidation of alkyl sulfides to sulfoxides or sulfones and direct aromatic halogenations may be conveniently performed after the tricyclic aromatic is spiro-imide derivatized, e.g., converted to the hydantoin or thiazolidinedione. In addition, certain labile protecting groups may be employed as is known and practiced in the art.
The four major derivatization methods to transform tricycles of Formulas II and III into derivatives of Formula I follow.
METHOD I
Spiro-Tricyclicimidazolidinediones (Hydantoin Derivatization)
The novel spiro-hydantoin derivatives of the present invention are readily prepared from appropriate ketones of Formula II, wherein A and B are previously defined. For example, spiro-imidazolidinedione derivatives (29) and (41) are prepared respectively from 5H-indeno[1,2-b]pyridin-5-one and 9H-pyrrolo[1,2-a]indolin-9-one: ##STR11## Similarly, spiro-imidazolidinedione derivative (39) is prepared from its starting material ketone 8H-indeno[2,1-b]thiophen-8-one: ##STR12## To synthesize a spiro-imidazolidinedione derivative, the ketone in Formula II is condensed with an alkali metal cyanide, such as potassium cyanide, and ammonium carbonate. The reaction is typically conducted in the presence of a ketone solubilizing inert polar organic solvent which include, but is not limited to, water miscible alcohols such as ethanol and isopropanol, lower alkylene glycols such as ethylene glycol and trimethylene glycol, N, N-di(lower alkyl), lower alkanoamides such as N,N-dimethyl-formamide, acetamide. In general, the reaction is conducted at temperatures ranging from 60° C. to about 180° C. (preferably 100° C. to 130° C.) for 6 hours to about 4 days, depending upon the ketone, solvent and temperature used. In general reagents in this reaction are employed in excess of stoichiometric amounts to provide maximum conversion of the ketone substrate to the spirohydantoin derivative. For example, a moderate excess of potassium cyanide (i.e., 1.1 equiv) and a 1.5 to 4 fold excess of ammonium carbonate achieves an increased yield of spirohydantoin derivative based upon ketone starting material. Reaction ketone substrates of Formula II are prepared by methods known to those skilled in the art. Typical preparative methods for substrate ketones are represented by, but are not limited to, examples in Table A and in the example preparations which follow.
METHOD II
Spiro-Tricyclicthiazolidinediones
The novel spiro-tricyclicthiazolidinedione derivatives of the present invention are readily prepared from appropriate fluorene and heterocyclic analogs of fluorene derivatives of Formula III, wherein A and B are previously defined. For example, spiro-thiazolidinedione derivative (26) is prepared from 5H-indeno[1,2-b]pyridine: ##STR13## Likewise, the spiro-thiazolidinedione of example (12) is prepared from its starting material 2-fluoro-9H-fluorene: ##STR14## The synthesis of a spiro-thiazolidinedione from the corresponding tricyclic fluorene or heterocyclic fluorene derivative is a multi-stepped synthesis as depicted in Example IV. The first step involves metalation with a lower alkyl lithium reagent such as n-butyllithium in an inert aprotic solvent such as diethyl ether or tetrahydrofuran under an inert atmosphere of nitrogen or argon, e.g., metalation of 2-fluoro-9H-fluorene: ##STR15## Metalation occurs primarily at the methylene bridge. Reaction with carbon dioxide results in carbonation of the bridge carbon to yield upon isolation the carboxylic acid, e.g., 2-fluoro-9H-fluoren-9-carboxylic acid: ##STR16## Isolation of the carboxylic acid derivative can be accomplished by a process including acidification, simple column chromatography and solvent recrystallization similar to the process cited in Example IV. In contrast to this general case, metalation and carbonation of 8H-indeno[1,2-c] thiophene results in a significant formation of 8H-indeno[1,2-c] thiophene-1-carboxylic acid and 8H-indeno[1,2-c] thiophene-3-carboxylic acid in addition to the desired 8H-indeno [1,2-c] thiophene-8-carboxylic acid, MacDowell and Jefferies; J. Org. Chem., 35 (1970) 871. The tricyclic carboxylic acid product is then esterified with a lower alkylalcohol such as methanol in the presence of an acid catalyst such as a hydrogen halide, such as hydrochloric acid. In a typical procedure, the acid (e.g., 2-fluoro-9H-fluorene- 9-carboxylic acid) is esterified by the addition of acetyl chloride to methanolic solution of the carboxylic acid with reflux: ##STR17## Proton abstraction from the acidic methine bridge of the carboxylic ester by an alkali alkoxide such as sodium metal in methanol or alkali hydride such as potassium hydride in DMSO or DMF generates a carbanion. Introduction of purified dry oxygen results in oxidation of the methine carbon. Bisulfite reduction and a simple work-up involving filtration results in the isolation of an α-hydroxy ester product, e.g., 2-fluoro-9-hydroxy-9H-fluoren-9-carboxylic acid methyl ester: ##STR18## α-Halogenation of the α-hydroxy ester by a thionyl halide such as thionyl chloride at reflux transforms 2-fluoro-9-hydroxy-9H-fluoren-9-carboxylic acid methyl ester into 9-chloro-2-fluoro-9H-fluoren-9-carboxylic acid methyl ester: ##STR19## In a typical work-up procedure the cooled reaction mixture is diluted with benzene or a similar inert solvent, as known to those skilled in the art, and the solution is evaporated with reduced pressure and heat to yield the α-halo ester. The α-halo ester, e.g., 9-chloro-2-fluoro-9H-fluoren-9-carboxylic acid methyl ester, is reacted with thiourea in an anhydrous polar high boiling relatively nonbasic solvent such as dioxane at reflux for 6-24 hours. Work-up and simple chromatography as is known to those skilled in the art results in the isolation of a spiro-tricyclicaminothiazolone product, e.g., spiro[2-fluoro-9H-fluoren-9,5'-(2'-amino-4'-thiazolone]: ##STR20## Hydrolysis of the spiro-aminothiazolone in an acidic aqueous alcoholic solution such as concentrated hydrochloric acid in methanol yields the spiro-thiazolidinedione, e.g., spiro-(2-fluoro-9H-fluorene-9,5'-thiazolidine)-2',4'-dione. ##STR21## Reaction starting materials, tricyclic fluorene and tricyclic heterocyclic flourene derivatives of Formula III, are prepared by methods known to those skilled in the art. Typical preparative methods are represented by, but are not limited to, preparation examples of Table A and in the examples which later follow.
METHOD III
Spiro-Tricyclicoxazolidinediones
The novel spiro-tricyclic-oxazolidinedione derivatives of the present invention are readily prepared from appropriate derivatives of flourene and heterotricyclic analogs of fluorene of Formula III, wherein A and B are previously defined. The synthesis of the spiro-oxazolidinediones and spiro-thiazolidinediones (see II) generally have common synthetic intermediates. For example, spiro-tricyclicoxazolidinedione derivative (6) is prepared from the tricyclic α-hydroxy ester, 2-fluoro-9-hydroxy-9H-fluorene-9-carboxylic acid methyl ester, which is an intermediate in the synthesis of spiro-tricyclic-thiazolidinedione (12). Reaction of the α-hydroxy ester with 1 to 2 (preferably 1.1) equivalents of urea and 1 to 2 (preferably 1.05) equivalents of an alkali alkoxide in a lower alkyl alcohol at reflux such as sodium ethoxide in ethanol yields the spiro-tricyclic-oxazolidinedione. The isolation procedure involves the addition of water to the reaction, acidification with a mineral acid such as hydrochloric acid, simple filtration and column chromatography. Such common product isolation procedures are well known to those skilled in the art. The isolated product, in this example, is spiro-(2-fluoro-9H-fluorene-9,5'-oxazolidinedione)-2',4'-dione.
Similarly, other tricyclic α-hydroxy esters known in the art are derived from the appropriate fluorene derivatives and heterotricyclic analogs of fluorene derivatives, as are represented in but not limited by those examples cited in Table A and in the following example preparations, can be utilized to prepare spiro-tricyclicoxazolidinediones according to this general scheme: ##STR22## M+=alkali metal cation (e.g., Na+) R=lower alkyl (e.g., methyl)
A and B are as previously defined.
METHOD IV
Spiro-Tricyclicsuccinimides
The novel spiro-tricyclicsuccinimide derivatives of the instant invention are readily prepared from appropriate fluorene derivatives and heterocyclic analogs of fluorene of Formula III, wherein A and B are previously defined. The synthesis of the spiro-tricyclicsuccinimides, spiro-oxazolidinediones and spiro-thiazolidinediones generally have common synthetic intermediates. For example, spiro-tricyclicsuccinimide derivatives (20) and (21) are prepared from the tricyclic acid esters, 9H-fluorene-9-carboxylic acid methyl ester and 2-fluoro-9H-fluorene-9-carboxylic acid methyl ester respectively which are intermediates in the synthesis of spiro-tricyclicthiazolidinediones (9) and (12) and spiro-tricyclicoxazolidinediones (2) and (6). Reaction of the carboxylic alkyl ester with 1 to 1.5 equivalents (preferably 1.1) of an alkali metal alkoxide such as sodium methoxide in an alkyl alcohol such as methanol followed by reaction with 1-2 equivalents (preferably 1.1) of 2haloacetamide such as 2-chloroacetamide (Aldrich Chemical, Inc.) at 10° to 50° C. (preferably ambient temperature) under an inert atmosphere such as nitrogen for a period of 8 hrs. to 4 days depending upon temperature, haloacetamide reagent and solvent employed. Typical reaction times with methanol solvent, chloroacetamide reagent at room temperature can be 48 hrs. The reacted mixture is typically poured into 1-4% volume of 1-5% alkali hydroxide such as 2.5% sodium hydroxide. Insolubles are removed by filtration. The filtrate is acidified with a dilute or concentrated mineral acid such as concentrated hydrochloric acid and the resulting precipitate is collected by filtration with cold water wash. Solvent recrystallizations may be employed as is known in the art to further purify the resulting spiro-tricyclicsuccinimide product. Specifically, 9H-fluorene-9-carboxylic acid methyl ester and 2-fluoro-9H-fluorene- 9-carboxylic acid methyl ester yield respectively, after the above treatment, spiro-(9H-fluoren-9,3'-succinimide) and spiro-(2-fluoro-9H-fluorene-9,3'-succinimide).
Similarly, other tricycliccarboxylic acid esters known in the art are derived from the fluorene derivatives and heterotricyclic analogs of fluorene and derivatives, as are represented in but not limited to those examples cited in Table A and in the following example preparations can be utilized to prepare spiro-tricyclicsuccinimides according to this general scheme: ##STR23## M+=alkali metal cation (e.g., Na+, K+) X=Cl, Br, I
R 1 =lower alkyl
R 2 =H, lower alkyl (preferably methyl)
A and B are as previously defined
METHOD V
HALOGENATION AND DERIVATIZATION OF FLUORENE, FLUORENONE AND THEIR INDENO-HETEROCYCLE ANALOGS AND DERIVATIVES
Halogenation of fluorene and fluorenone and related indeno heterocycle analogs such as 4-azafluorene or 4-azafluorenone and as exampled in Table A where Q is dihydrogen and oxygen can be accomplished by methods known and practiced in the art (e.g., Eckert and Langecker, J. Prakt. Chem., 118, 263 (1928); Courot, Ann. Chem., 14, 5 (1930); Bell and Mulholland, J. Chem. Soc., 2020 (1949); Johnson and Klassen, J. Chem. Soc., 988 (1962)). In general, chlorination of fluorenone and flourene derivatives and related heterocyclic indeno analogs is accomplished by dissolving the substrate in glacial acetic acid containing anhydrous ferric chloride (10-20% by weight of substrate) and chlorine gas or chlorine dissolved in glacial acetic acid (1.2 to 3.0 molar equiv.) is added. The reaction is stirred at a selected temperature for several hours and allowed to cool; the crude product is isolated and solvent recrystallized to yield the chlorinated derivative.
The structure-reactivity of tricyclic azines, nitrogen analogs of fluorenone and fluorene, to electrophillic halogenation has been characterized by Mlochowski and Szulc, J. Prakt. Chem., 322 (1980) 971.
Fluorination of selected derivatives of fluorene (and fluorenone) and indeno heterocyclic analogs involves a multistepped process wherein the substrate is first nitrated (Kretor and Litvinov, Zh. Obsch. Khim., 31, 2585 (1961); Org. Syntheses, Coll. Vol. II, 447 (1943); Org. Syntheses, Coll. Vol. V, 30 (1973)). The resulting nitro derivative is reduced via Raney nickel and hydrazine, zinc dust and calcium chloride, iron fillings and concentrated hydrochloride acid, palladium on carbon with hydrazine and other methods known to the art (Org. Syntheses Coll. Vol. II, 447 (1943); Org. Snytheses Coll. Vol. V, 30 (1973); Fletcher and Namkung, J. Org. Chem., 23, 680 (1958)). The resulting aromatic amine(s): (a) is subjected to the Schiemann reaction according to the method of Fletcher and Namkung, Chem. and Ind., 1961, 179, wherein the ammonium fluoroborate salt, prepared in the presence of tetrahydrofuran is first diazotized and then decomposed in hot xylene to yield the corresponding fluoro derivative. Oxidation of the fluoro derivative, e.g., 2-fluoro-9H-flourene, according to Sprinzak, J. Amer. Chem. Soc., 80, 5449 (1958) or by other oxidation procedures known and practiced in the art, yields the ketone, e.g., 2-fluoro-9H-fluoren-9-one. In a general and novel process cited in U.S. Pat. Nos. 4,438,272 and 4,436,745, the fluorinated ketone is converted into the corresponding alkylsulfide, alkylsulfoxide and/or alkylsulfone. An alkaline metal alkylsulfide nucleophile (e.g., sodium methylthiolate in DMF) displaces fluoride to yield the corresponding alkylsulfide derivative, e.g., 2-methyl-thiol-9H-fluoren-9-one. The resulting alkylsulfide derivative can be oxidized by known procedures (e.g., sodium metaperiodate or hydrogen peroxide) to the corresponding sulfoxide and/or sulfone; (b) as hydrogen halide salt(s) is diazotized by sodium nitrate. Replacement of the diazonium group(s) in these aromatic derivatives by a halo or cyano group(s) (e.g., via KNC) salts (Sandmeyer), copper powder (Gatterman) or cupric salts (Korner-Contardi). See Organic Synthesis Vol. I, p. 170 (1932); E. Pfeil, Angew. Chem., 65, 155 (1953); Y. Nakatani, Tetrahedron Lett., 1970, 4455. As is known in the art, the resulting cyano derivatives can be hydrolyzed into carboxylic acids; alcoholyzed to carboalkoxy esters, e.g., carboethoxy esters; hydrolyzed to carboxamide; reduced to methylamine, etc., as is well known and practiced in the art. Other aromatic derivatizations can similarly be made by those skilled in the art. According to a general process of Teulin et al., J. Med. Chem., 21 (1978) 901, tricyclic indeno derivatives with the general formula: ##STR24## (where B is a previously defined) are derivatized to the corresponding arylisopropanoic and arylacetic acids. The process involves the following synthetic steps: ##STR25## In accordance with Method VII the aforementioned indeno derivatives can be oxidized to the corresponding ketones which are starting material substrates for spiro-hydantoin derivatization in accordance with Method I.
A serial process involving several of the aforementioned processes can be employed to introduce for example a fluoro, and a chloro substituent into the same tricyclic-aromatic substrate. Other fluorene and fluorenone derivatives and indeno heterocyclic analog derivatives can be prepared in accordance with common synthetic procedures known and practiced in the art.
Finally, tricyclic aromatic azine derivative such as 5H-indeno[1,2b]pyridine-5-one or 5H-indeno[1,2-b]pyridine, can be pyridine N-oxidized to yield the corresponding pyridine N-oxide derivative. Such an N-oxide is employed to prepare the corresponding spiro-hydantoin derivative according to Method I or spiro-oxazolidinedione and spiro-succinimide according to Methods III and IV respectively. For example, ##STR26##
METHOD VI
The novel spiro-tricyclic-imidazolidinediones, -thiazolidinediones, -oxazolidinediones and -succinimides may be further derivatized according to the following.
Nitrated fluorenone will not easily derivatize to form the corresponding spiro-hydantoin.
The preferred method of preparation of spiro-hydantoin aromatic nitro derivatives is via direct nitration (e.g., via nitric acid and 60% sulfuric acid) of the spiro-cyclic derivatives, especially spiro-hydantoin (see Example XI). After nitration of the selected spiro-tricyclic-imidazolidinediones, -thiazolidinediones, -oxazolidinediones and succinimides by methods well known and practiced in the art, the corresponding aromatic nitro group(s) of corresponding spiro-tricyclic derivative(s) of the present invention can be reduced to the corresponding amine derivative(s). Aromatic nitro group(s) reduction to the aromatic amine(s) can be accomplished by a number of methods including reduction by hydrazine hydrate and Raney Nickel (see Fletcher and Namkung, J. Org. Chem., 23, 680 (1958). The resulting amine(s) as hydrogen halide salt(s) is diazotized by sodium nitrite. Replacement of the diazonium group(s) in these aromatic derivatives by a halo or cyano group(s) (e.g., via KCN) salts (Sandmeyer), copper powder (Gatterman) or cupric salts (Korner-Contardi). See Organic Synthesis Vol. I, p. 170 (1932); E. Pfeil, Angew. Chem., 65, 155 (1953); Y. Nakatani, Tetrahedron Lett., 1970, 4455. As is known in the art, the resulting cyano derivatives can be hydrolyzed into carboxylic acids; alcoholyzed to carboalkoxy esters, e.g., carboethoxy esters; hydrolyzed to carboxamide; reduced to methylamine, etc., as is well known and practiced in the art. Other aromatic derivatizations can similarly be made by those skilled in the art.
Spiro-tricyclic azine derivative, such as spiro-(7-fluoro-5H-indeno [1,2-b]pyridine-5,4'-imidazolidine)-2',5'-dione, is oxidized to the corresponding N-oxide derivative according to the general procedure of Mosher et al., Org. Syn., 33 (1953) 79 wherein peracetic acid is employed as the oxidizer. Such as N-oxide is active as aldose reductase inhibitor. For example, ##STR27##
METHOD VII
Heterocyclic analogues of fluorene and fluorene derivatives such as 1-azafluorene and 2-fluoroflourene can be transformed into corresponding ketones (e.g., 1-azafluorenone or 2-fluorofluorenone) via a number of oxidation procedures which are well known to those skilled in the art. Some relevant representative methods include:
a) Oxidation by oxygen under basic conditions according to a general procedure of U. Sprinzak, J. Amer. Chem. Soc., 80 (1958) 5449.
b) Oxidation by permanganate in which the flourene derivative is oxidized by potassium permanganate in acetone, e.g., see Urbina, Synthetic Communications 9 (1979), 245.
c) Oxidation by selenium dioxide in a sealed vessel at 200°-250° C. when common oxidation procedures such as chromium trioxide in acetic acid are ineffective. See Arcus and Barnett, J. Chem. Soc. (1960) 2098.
METHOD VIII
Tricyclic ketones of the present invention may be reduced to the corresponding methylene reduction product by the Wolff-Kishner Reduction or by the Huang-Minlon modified Wolff-Kishner Reduction (see also MacDowell and Jefferies, J. Org. Chem., 35, 871 (1970)). Alternatively, these ketones may be reduced by lithium aluminum hydride in the presence of aluminum chloride (see Rault, Lancelot and Effi, Heterocycles 20, 477 (1983)) or by other reduction methods known to those skilled in the art.
METHOD OF TREATMENT IX
The spiro-tricyclic-thiazolidinedione, -imidazolidinedione, -oxazolidinedione and -succinimide compounds of the present invention are weak acids. In addition, several examples, as cited in Example XIX, are carboxylic acid derivatives and/or aromatic azines (i.e., contain a basic nitrogen(s) in the aromatic tricycle) and/or contain an alkylamine substituent. Therefore, these compounds are ameanble to preparation as base salts and in some cases, where basic amines are present, acid salts. Several examples contain both an acidic spiro functionality and carboxylic acid functionality. These cases can be prepared as mono- or di-basic salts.
The chemical bases which are used as reagents to prepare the aforementioned pharmaceutically acceptable base salts those which form nontoxic (pharmaceutically acceptable) salts with the various herein described acidic spiro-imidazolidinedione, -thiazolidine-dione, -oxazolidinedione and -succinimide derivatives such as spiro-(7-fluoro-5-H-indeno[1,2-b] pyridine-5,4'-imidazolidine)-2,',5'-dione, for example. Similarly, herein described carboxylic acid containing derivatives, such as spiro-(2-carboxy-9H-fluoren-9,5'-thiazolidine)-2',4'-dione, can be prepared as nontoxic salts. These nontoxic base salts are of a nature not to be considered clinically toxic over a wide therapeutic dose range. Examples of such cations of such cations include those of sodium, potassium, calcium, magnesium, etc. These pharmacologically acceptable nontoxic salts can be prepared by treating the aforementioned acidic specie, e.g., spiro-thiazolidinedione, with aqueous metallic hydroxide solution, and then evaporating the resulting solution, preferably at reduced pressure, to dryness. Alternatively, where indicated, the base salts can be prepared by mixing a lower alkanolic solution (e.g., ethanol) of the acidic compound with a desired alkali metal alkoxide (e.g., sodium ethoxide) in a lower alkanolic solution, and evaporating the solution to dryness in the same manner as before. In any case stoichiometric quantities of reagents must be employed in order to ensure completeness of reaction and maximum production of yields with respect to the final base salt product.
Acid salts of spiro-tricyclic azine derivatives, e.g., spiro-(7-fluoro-5H-indeno[1,2b]pyridine-5,5'-thiazolidine)-2',4'-dione, can be prepared with nontoxic pharmacologically acceptable acids, e.g., hydrochloric acid and sulfuric acid. Examples of such anions of said acid salts include those of hydrogensulfate, sulfate, chloride, etc. These pharmacologically acceptable nontoxic acid salts can be prepared by treating the aforementioned basic specie, e.g., spiro-azafluorene derivative, with an acidic aqueous solution of the desired acid. After the basic species is solubilized in the acid, the solution is evaporated to dryness, preferably with reduced pressure. In this case, stoichiometric quantities of acid are preferred. Alternatively, in some cases the acid salt may be precipitated or recrystallized from strong acid solution (e.g., 5% hydrochloric acid). The salt then is collected by filtration and dried.
As previously indicated, the spiro-tricyclic-thiazolidinedione, -imidazolidinedione, -oxazolidinedione and -succinimide compounds of this invention are all readily adapted to therapeutic use as aldose reductase inhibitors for the control of chronic diabetic complications, in view of their ability to reduce lens sorbitol levels in diabetic subjects to a statistically significant degree. The herein described compounds of this invention can be administered by either the oral or parenteral routes of administration. In general, these compounds are ordinarily administered in dosages ranging from about 0.1 mg to about 10 mg/kg of body weight per day, although variations will necessarily occur depending upon the weight and condition of the subject being treated and the particular route of administration chosen; the preferred range is 0.5 to 4.0 mg/kg. Oral administration is preferred.
While matters of administration are left to the routine discretion of the clinician, long term, prophylactic administration of the compounds of the present invention is generally indicated on diagnosis of diabetes mellitus and/or neuropathy and/or retinopathy and/or vasculopathy and/or cataract and/or impaired wound healing and/or nephropathy and/or hyperglyceamia.
In connection with the use of the spiro-tricycle compounds of this invention for the treatment of diabetic subjects, it is to be noted that these compounds may be administered either alone or in combination with pharmaceutically acceptable carriers by either of the routes previously indicated, and that such administration can be carried out in both single and multiple dosages. More particularly, the compounds of this invention can be administered in a wide variety of different dosage forms, i.e., they may be combined with various pharmaceutically acceptable inert carriers in the form of tablets, capsules, lozenges, troches, hard candies, powders, sprays, aqueous suspensions, injectable solutions, elixirs, syrups, and the like. Such carriers include solid diluents of fillers, sterile aqueous media and various nontoxic organic solvent, etc. Moreover, such oral pharmaceutical formulations may be suitably sweetened and/or flavored by means of various agents of the type commonly employed for just such purposes. In general, the therapeutically useful compounds of this invention are present in such dosages forms at concentration levels ranging from about 0.5% to about 90% by weight of the total composition, i.e., in amounts which are sufficient to provide the desired unit dosage.
For purposes or oral administration, tablets containing various excipients such as sodium citrate, calcium carbonate and calcium phosphate may be employed along with various disintegrants such as starch and preferably potato or tapioca starch, alginic acid and certain complex silicates, together with binding agents such as polyvinylpyrrolidone, sucrose, gelatin and acacia. Additionally, lubricating agents such as magnesium stearate, sodium lauryl sulfate and talc are often very useful for tabletting purposes. Solid compositions of a similar type may also be employed as fillers in soft and hard-filled gelatin capsules; preferred materials in this connection would also include lactose or milk sugar as well as high molecular weight polyethylene glycols. When aqueous suspensions and/or elixirs are desired for oral administration, the essential active ingredient therein may be combined with various sweetening or flavoring agents, coloring matter of dyes, and if so desired, emulsifying and/or suspending agents as well, together with such diluents as water, ethanol, propylene glycol, glycerin and various like combinations thereof.
For purposes of parenteral administration, solutions of these particular spiro-tricycles in sesame or peanut oil or in aqueous propylene glycol may be employed, as well as sterile aqueous solutions of the corresponding water-soluble, alkali metal or alkaline-earth metal or acid salts previously enumerated. Such aqueous solutions should be suitable buffered if necessary and the liquid diluent first rendered isotonic with sufficient saline or glucose. These particular aqueous solutions are especially suitable for intravenous, intramuscular, subcutaneous and intraperitoneal injection purposes. In this connection, the sterile aqueous media employed are all readily obtainable by standard techniques well-known to those skilled in the art. Additionally, it also is possible to administer the aforesaid spiro-tricycle compounds topically via an appropriate ophthalmic solution suitable for the present purposes at hand, which can then be given dropwise to the eye.
The activity of the compounds of the present invention, as agents for the control of chronic diabetic complications, is determined by their ability to successfully pass one or more of the following standard biological and/or pharmacological test, viz., (1) measuring their ability to inhibit the enzyme activity of isolated human aldose reductase; (2) measuring their ability to reduce or inhibit enzyme activity of rat lens aldose reductase in vitro; (3) measuring their ability to preserve motor nerve conduction velocity in chronic streptozotocin-induced diabetic rats; (4) and measuring their ability to delay cataract formation and reduce the severity of lens opacities in chronic galactosemic rats; (5) measuring with electron microscopy their ability to prevent basement membrane thickening in the kidney glomerulus and/or retina capillaries in chronic streptozotocin-induced diabetic rats (6) measuring their ability to maintain rat lenses in 30 mM xylose culture for 18 h.
Typical preparative methods and synthetic design for substituted analogs of the tricycles of Table A and Formulas II and III are provided for instruction.
x, y and z are as previously defined.
Where Q=H 2 or O
TABLE A______________________________________Substrates and Derivatives Method of Preparation______________________________________ ##STR28## A ##STR29## B ##STR30## C ##STR31## D ##STR32## E ##STR33## E ##STR34## E ##STR35## E ##STR36## E ##STR37## F ##STR38## G ##STR39## H ##STR40## I ##STR41## J ##STR42## J ##STR43## J ##STR44## J ##STR45## J ##STR46## K ##STR47## L ##STR48## M ##STR49## N ##STR50## O ##STR51## O ##STR52## P ##STR53## P ##STR54## P ##STR55## P ##STR56## P ##STR57## P ##STR58## Q______________________________________
PREPARATION A
Synthesis substrates 8H-indeno[2,1-b]thiophen-8-one and 8H-indeno [2,1-b]thiophene and their derivatives are prepared in accordance with the following by a general method of Venin, Brault and Kerfanto, C. R. Acad. Sc. Paris, 266 (c), 1650 (1968), various substituted phenylglyoxals are prepared in a three step process involving: gem dibromination of the substituted acetophenone (e.g., p-fluoroacetophenone) to the corresponding α,α-dibromoacetophenone; nucleophillic displacement of the gem bromides to yield the corresponding aminal; aqueous acid (e.g., dilute HCl) hydrolysis to yield the substituted phenylgloxal, e.g., p-fluorophenylglyoxal. By such a process the following substituted phenylglyoxals are prepared: ##STR59## X and Y=H, halogen, lower alkyl, lower cycloalkyl, COOH, C.tbd.N, --O--R, --S--R, --S(O)R, --SO 2 R
R=Lower alkyl
from commercially available substituted acetophenones (e.g., o-, p- or m- fluoro- chloro- or bromo-acetophenone may be purchased from Aldrich Chemical, Inc.). Other substituted acetophenones are prepared by methods well known to those skilled in the art. Phenglyoxal (Aldrich Chemical, Inc.) is commercially available. Such prepared substituted phenylglyoxals (e.g., 4'-fluorophenylglyoxal) are utilized to synthesize corresponding substituted 8H-indeno[2,1-b]thiophen-8-one and 8H-indeno[2,1-b]thiophene substrates which are derivatized by Methods I-IV. The synthesis of substituted 8H-indeno[2,1-b]thiophen-8-one involves the Hinsberg Stobbe type condensation (Wolf and Folkers, Org. Reactions, 6, 410 (1951)) between the substituted phenylglyoxal, e.g., 4'-fluorophenylglyoxal, and diethylthiodiglycolate using sodium ethoxide. After saponification, the isolated substituted 3-phenyl-2,5-thiophenedicarboxylic acid, e.g., 3-(4'-fluorophenyl)-2,5-thiophenedicarboxylic acid is treated with thionyl chloride to form the diacylchloride which is intramolecularly cyclized by a Friedel-Crafts reaction catalyzed by aluminum chloride or stannic chloride to give the correspondingly substituted 8-oxo-8H-indeno-[2,1-b]thiophen-2-carboxylic acid, e.g., 6-fluoro-8-oxo-8H-indeno-[2,1-b]thiophen-2-carboxylic acid, (A-1), which can be converted into a hydantoin derivative according to Method I. Decarboxylation of (A-1) by copper powder in anhydrous quinoline yields the corresponding substituted 8-indeno-[2,1-b]thiophen-8-one (A-2) which is converted (in accordance with Method I) into a hydantoin derivative such as spiro-(6-fluoro-8H-indeno[2,1-b]thiophen-8,4'-imidazolidine)-2',5'-dione. See Example XIV for the preparation of spiro-(8H-indeno[2,1-b]thiophen-8,4'-imidazolidine)-2',5'-dione. The Wolff-Kishner reduction (Method VIII) of (A-1) or (A-2), preferably (A-1), yields the corresponding substituted 8H-indeno[2,1-b]thiophene, e.g., 6-fluoro-8H-indeno-[2,1]thiophene. In the alkaline hydrazine (in excess) reduction of the ketoacid (A-1), both keto reduction and decarboxylation may occur. Product isolation is best accomplished by fractional distillation, but may involve other separation methods as are known in the art. Further derivatization may be accomplished according to Method V. The resulting substituted 8H-indeno[2,1-b]thiophene is metalated by n-butyllithium and carbonated in the methylene bridge to yield the corresponding 8-carboxylic acid which, after esterification, at reflux with a lower alkyl alcohol such as methanol under acid catalyzed conditions such as concentrated hydrochloric acid yields the corresponding substituted or unsubstituted 8H-indeno 2,1-b]thiophen-8-carboxylic acid alkyl ester, e.g., 6-fluoro-8H-indeno[2,1-b]thiophen-8-carboxylic acid methyl ester. The ester is utilized according to Methods II, III and IV to yield the corresponding spiro-thiazolidinedione, spiro-oxazolidine-dione and spiro-succinimide such as spiro-(6-fluoro-8H-indeno[2,1-b]thiophen-8,5'-thiazolidine)-2',4'-dione, spiro-(6-fluoro-8H-indeno-8,5'-oxazolidine)-2,4'-dione and spiro-(6-fluoro-8H-indeno[2,1-b]thiophen-8,3'-succinimide) respectively.
PREPARATION B
Synthesis substrates 4H-indeno[1,2-b]thiophen-4-one and 4H-indeno [1,2-b]thiophene can be prepared according to a general process of MacDowell and Jefferies, J. Org. Chem., 35, 871 (1970). In this process the 4-one substrate is prepared by the Ullmann coupling of ortho-iodo or ortho-bromo, di, tri and tetrasubstituted benzoic acid lower alkyl esters, such as 3-fluoro-2-iodo-benzoic acid ethyl or methyl ester (Chem. Abst.; 27:1339/G) or 2-bromo-4-fluoro-benzoic acid methyl ester (Chem. Abst. 99(1):5630j) or 2-bromo-5-chlorobenzoic acid methyl ester (J. Med. Chem., 13, 567-8 (1970)) with 2-iodo or 2-bromothiophene (Aldrich Chemical, Inc.). Saponification of the coupled product will yield the corresponding substituted 2-(2'-thienyl) benzoic acid (e.g., 5-chloro-2-(2'-thienyl)benzoic acid from 2-bromo-5-chloro-benzoic acid methyl ester. Cyclization of the acid is performed via the aroyl halide using stannic chloride or aluminum chloride to yield to substituted 4H-indeno[ 1,2-b]thiophen-4-one (B-1) (e.g., 6-chloro-4H-indeno[1,2-b]thiophen-4-one). This 4-one derivative is converted (in accordance with Method I) into a hydantoin derivative such as spiro-(6-chloro-4H-indeno[1,2-b]thiophen-4,4'-imidazolidine)-2',5'-dione. See Example XIII for the preparation of spiro-(4H-indeno[1,2]thiophen-4,4'-imidazolidine)-2',5'-dione. The Wolff-Kishner reduction (Method VIII) of B-1) yields the corresponding 4H-indeno[1,2-b]thiophene. Product isolation is best accomplished by fractional distillation, but may involve other separation methods as are known in the art. The resulting substituted or unsubstituted 4H-indeno[1,2-b]thiophene (which may be further derivatized according to Method V) is metalated by n-butyllithium and carbonated in the methylene bridge to yield the corresponding 4-carboxylic acid which after esterification at reflux with a lower alkyl alcohol such as methanol under acid catalyzed conditions such as concentrated hydrochloride acid yields the corresponding substituted or unsubstituted 4H-indeno[1,2-b]thiophen-4-carboxylic acid lower alkyl ester, e.g., 6-chloro-4H-indeno[1,2-b]thiophen-4-carboxylic acid methyl ester. The ester is utilized according to Methods II, III and IV to yield the corresponding spiro-thiazolidinedione, spiro-oxazolidinedione and spiro-succinimide such as spiro-(6-chloro-4H-indeno[1,2-b]thiophen-4,5'-thiazolidine]-2',4'-dione, spiro-(6-chloro-4H-indeno[1,2-b]thiophen-4,5'-oxazolidine)-2',4'-dione and spiro-(6-chloro-4H-indeno[1,2-b]thiophen-4,3'-succinimide) respectively. The resulting spiro-derivatives may be further derivatized according to Method VI.
PREPARATION C
Synthesis substrates 4H-indeno[1,2-c]thiophen-4-one and 4H-indeno[1,2-c]thiophene and their derivatives are prepared in accordance with MacDowell and Jefferies, J. Org. Chem., 35, 871 (1970). Wherein treatment of 4-bromo-3-thienyllithium with a commonly available lower alkyl substituted cyclohexanone or cyclohexanone, such as 4-methylcyclohexanone, at -65° to -75° C. yields the corresponding cyclohexanol derivative which is dehydrated with para-toluenesulfonic acid in refluxing benzene or toluene to yield a cyclohexylthiophene product such as 3-bromo-4-(4-methyl-1'-cyclohexenyl)thiophene. Dehydrogenation with tetrachlorobenzoquinone in refluxing xylene for 8-24 hours yields the corresponding 3-bromo-4-phenylthiophene, e.g., 3-bromo-4-(4'-methylphenyl)thiophene. After purification by sublimation and/or chromatography over alumina, the bromide is subjected to halogen-metal exchange at -65° to -75° C. with n-butyllithium in ether, followed by carbonation with carbon dioxide. The isolated 3-phenyl-thiophene-4-carboxylic acid derivatives, e.g., 3-(4'-methylphenyl)thiophene-4-carboxylic acid, is converted with thionyl chloride to the acid halide. Ring closure to the ketone via heating the aroyl chloride and aluminum chloride in carbon disulfide for 18-36 hours yields the corresponding ketone, such as 6-methyl-8H-indeno[1,2 -c]thiophen-8-one. This 8-one derivative, which may be further derivatized according to Method V, is converted (in accordance with Method I) into a hydantoin derivative. Wolff-Kishner reduction (Method VIII) of the 8-one derivative (and optional derivatization according to Method V) and spiro-derivatization in accordance with Methods II, III and IV yields the corresponding spiro-thiazolidinedione, spiro-oxazolidinedione and spiro-succinimide derivatives respectively. These spiro-derivatives may be further derivatized according to Method VI.
PREPARATION D
Synthesis substrate 7H-cyclopenta[1,2-b:4,3-b']dithiophene is prepared according to the method of Wynberg and Kraak, J. Org. Chem., 29, 2455 (1964). The corresponding spiro-thiazolidinedione, spiro-oxazolidinedione and spiro-succinimide derivatives are prepared according to Methods II-IV respectively. The 7-one derivative is prepared from the cyclopentadithiophene in accordance with the oxidation procedures in Method VII. The ketone, 7Hcyclopenta[1,2-b:4,3-b]dithiophen-7-one is converted into the spiro-hydantoin derivative in accordance with Method I.
PREPARATION E
Synthesis substrates 4H-cyclopenta[2,1-b:3,4-b']dithiophene,7H-cyclopenta[1,2-b:3,4-b']dithiophene, 7H-cyclopenta[1,2-c:3,4-c']dithiophene, 7H-cyclopenta[1,2-b:3,4-c']dithiophene and 7H-cyclopenta[2,1-b:3,4-c']dithiophene are prepared according to the procedure of Wiersema and Wynberg, Tetrahedron, 24, 3381 (1968). From these, the corresponding spiro-thiazolidinedione, spiro-oxazolidinedione and spiro-succinimide derivatives are prepared according to Methods II-IV respectively. The corresponding 4H-cyclopenta[2,1-b:3,4-b']dithiophen-4-one, 7H-cyclopenta[1,2-b:3,4-b']dithiophen-7-one, 7H-cyclopenta[1,2-c:3,4c']dithiophen-7-one, 7H-cyclopenta[1,2-b:3,4-c']dithiophen-7-one and 7H-cyclopenta[2,1-b:3,4-c']dithiophen-7-one are prepared in accordance with the oxidation procedure cited in Method VII. The resulting ketones are spiro-hydantoin derivatized in accordance with Method I.
PREPARATION F
Synthesis substrates 5H-indeno[1,2-b]pyridin-5-one and 5H-indeno[1,2-b]pyridine (as 4-azafluorene from Aldrich Chemical, Inc.) and their derivatives are prepared according to a general procedure of Parcell and Hauck, J. Org. Chem., 21, 3468 (1963), wherein the piperidineenamine of 2,3-dihydro-1H-inden-1-one (available from Aldrich Chemical, Inc.) --4,--5 or --6-chloro or fluoro-2,3-dihydro-1H-inden-1-one (Oliver and Marechal, Bull. Soc. Chim. France, (1973), 3092), 6-chloro-5-cyclopentylmethyl-2,3-dihydro-1H-inden-1-one (Biere et al., Eur. J. Med., 18, 255 (1983), 5,6-dimethoxy-2,3-dihydro-1H-inden-1-one (Koo, J. Amer. Chem. Soc., 75, 1891 (1953)), 5 or 6-methoxy-2,3-dihydro-1H-inden-1-one (available from Aldrich Chemical, Inc.,) or other substituted 1-indanones is formed from piperidine in the presence of p-toluenesulfonic acid catalyst according to the procedure of Heyl and Herr, J. Amer. Chem. Soc., 75, 1918 (1953). The resulting piperidineenamine is reacted with 3-bromopropylamine hydrobromide or hydrochloride (available from Aldrich Chemical, Inc.) to yield an imine product.
The process typically involves the addition of 1.1 molar equivalents of the enamine to 1 molar equivalent of bromopropylamine hydrobromide in dimethylformamide at elevated temperature until the exothermic reaction is initiated wherein the temperature is kept at 90°-120° C. for several hours. The product is isolated by a combination of acidification and ether washing followed by basification and ether extractions. Evaporation yields the tetrahydroimine product such as: ##STR60## The tetrahydroimine product is aromatized in xylene and nitrobenzene and 10% palladium on charcoal according to Parcell and Hauch, ibid. The resulting product, e.g., 7-fluoro-5H-indeno[1,2-b]pyridine (which may be further derivatized according to Method V) is derivatized according to Methods II and IV to yield the corresponding spiro-derivatives such as spiro-(7-fluoro-5H-indeno[1,2-b]pyridin-5,5-thiazolidine)-2',4'-dione; spiro-(7-fluoro-5H-inden[1,2-b]pyridin-5,5'-(oxazolidine-2',4'-dione and spiro-(7-fluoro-5H-indeno[1,2-b]pyridin-5,3'-succinimide. Oxidation (Method VII) of 5H-indeno[1,2-b]pyridine or its derivatives according to the method of Sprinzak, J. Amer. Chem. Soc., 80, 5449 (1958) yields the corresponding 5-one or ketone derivative, which may be further derivatized according to Method V. When reacted in accordance with Method I, the ketone will yield a spiro-hydantoin derivative such as spiro-(7-fluoro-5H-indeno[1,2-b]pyridin-5,5'-imidazolidine)-2',5'-dione. Any of the aforementioned spiro derivatives may be further derivatized, e.g., nitrated, in accordance with Method VI. See Examples XVIII, XI and XII.
PREPARATION G
Synthesis substrates 5H-indeno[1,2-c]pyridin-5-one and 5H-indeno[1,2-c]pyridine and their derivatives may be prepared in accordance with the following. 3-Azafluorenone (5H-indeno[1,2-c]-pyridin-5-one) is prepared according to the method of Mayor and Wentrup, J. Amer. Chem. Soc., 97, 7467 (1975). The ketone can be derivatized in accordance with Method V. The ketone, e.g., 5H-indeno[1,2-c]pyridin-5-one, is hydantoin derivatized according to Method I. A Wolff-Kishner reduction (Method VIII) of this 3-azafluorenone can be accomplished according to Kloc et al., Heterocycles 9, 849 (1978) to yield the corresponding 5H-indeno[1,2-c]pyridine which is derivatized in accordance with Methods II-IV to yield the corresponding spiro-thiazolidinedione, spiro-oxazolidinedione and spiro-succinimide respectively. The aforementioned spiro-derivatives may be further derivatized according to Method VI.
PREPARATION H
Synthesis substrates 9H-indeno[2,1-c]pyridin-9-one and 9H-indeno[2,1-c]pyridine are prepared according to the method of Mayor and Wentrup, J. Amer. Chem. Soc., 97, 7467 (1975). Further derivatization may be accomplished in accordance with Method V. The resulting indenopyridine or 2-azafluorene product is further derivatized according to Methods II-IV to yield the spiro-thiazolidinedione, spiro-oxazolidinedione and spiro-succinimide derivatives. Oxidation of the indenopyridine to the corresponding ketone is accomplished by sodium dichromate or other oxidation procedures as cited in Table A. The resulting ketone may be derivatized in accordance with Method V. The selected 2-azafluoreneone derivative is derivatized to yield the spiro-hydantoin. See Example XVI for the preparation of spiro-(9H-indeno[2,1-c]pyridin-9,4'-imidazolidine)-2',5'-dione. The aforementioned spiro-derivatives may be further derivatized according to Method VI.
Furthermore, in example, 7-amino-2-azafluorene or 7-amino-9H-indeno[2,1-c]pyridine can be prepared according to the method of Perin-Roussel and Jacquignon, C. R. Acad. Sc. Paris, 278, 279 (1974). This amino product, in accordance with Method V, can be transformed via the Schiemann reaction into 7-fluoro-9H-indeno[2,1-c]pyridine. This substrate, as above, can be transformed by Methods I-IV into spiro-(7-fluoro 9H-indeno[2,1-c]pyridin-9,4'-imidazolidine)-2',5'-dione, spiro-(7-fluoro 9H-indeno[2,1-c]pyridin-9,5'-thiazolidinedione)-2',4'-dione, spiro-(7-fluoro 9H-indeno[2,1-c]pyridin-9,5'-oxazolidine)-2,4'-dione and spiro-(7-fluoro 9H-indeno[2,1-c]pyridin-9,3'-succinimide).
PREPARATION I
The ketone substrate, 9H-indeno[2,1-b]pyridin-9-one may be prepared by the method of Kloc, Michowski and Szulc, J. prakt. chemie, 319, 95q (1977). This ketone can be derivatized according to Method V. The substituted or unsubstituted ketone is then derivatized in accordance with Method I to yield the spiro-hydantoin which may be further modified according to Method VI.
The ketone, from the above, is reduced to a method cited in Method VIII or in general the Wolff-Kishner reduction to yield corresponding 9H-indeno[2,1-b]pyridine which is then derivatized in accordance with Methods II, III and IV to yield spiro-thiazolidinedione, spiro-succinimide.
Alternatively, 5H-indeno[2,1-b]pyridine-5-one (also called 1-azafluoren-9-one) and 5 to 8 position fluoro or chloro derivatives are prepared according to a general procedure of Urbina, Synthetic Comm., 9, 245(1979). Where to a substituted or unsubstituted 1-phenyl-2-propanone (e.g., 1-(4'-fluorophenyl)-2-propanone) is added acrylonitrile producing a corresponding 5-cyano-3-phenyl-2-pentanone, e.g., 5-cyano-3-(4'-fluorophenyl)-2-pentanone. The pentanone product is hydrogenated and cyclized to the corresponding 2-methyl-3-phenylpiperidine, e.g., 2-methyl-3-(4'-fluorophenyl)piperidine. Aromatization of the 2-methyl-3-phenyl piperidine is carried out in vapor phase with catalyst K-16 (Prostakon, Mathew and Kurisher, Khim-Geterotsikl. Soed., 876 (1970)) at 380° to 420° C. to yield the corresponding 2-methyl-3-phenylpyridine. Alternatively, aromatization can be achieved with Pd/C. Dehydrocyclization of the methyl-3-phenylpyridine at 500° to 550° C. over K- 16 will produce the appropriate 1-azafluorene, e.g., 7-fluoro-1-azafluorene. The 9H-indeno[2,1-b]pyridine and its derivatives (e.g., 7-fluoro-9H-indeno[2,1-b]pyridine) are converted in accordance with Method II, III and IV into spiro-thiazolidinedione, spiro-oxazolidinedione and spiro-succinimide derivatives. The 9H-indeno[2,1-b]pyridine is oxidized according to general procedures cited in Method VII or potassium permanganate (Urbina, ibid). The resulting ketone, e.g., 7-fluoro-9H-indeno[2,1-b]pyridine-5-one, is derivatized in accordance with Method I to yield the spiro-hydantoin derivative, such as spiro-(7-fluoro-9H-indeno[2,1-b]pyridin-9,4'-imidazolidine)-2',5'-dione.
PREPARATION J
Synthetic substrates 5H-cyclopenta[2,1-b:4,3-b']dipyridin-5-one, 5H-cyclopenta[1,2-b:3,4-c']dipyridin-5-one, 5H-cyclopenta[1,2-b:4,3-b'] dipyridin-5-one, 5H-cyclopenta[2,1-b:4,3-c']dipyridin-5-one, 5H-cyclopenta,,[1,2-b:3,4-c']dipyridin-5-one, 5H-cyclopenta-[1,2-b:4,3-b']dipyridin-5-one, 5H-cyclopenta[2,1-b:4,3-c']dipyridin-5-one, 5H-cyclopenta-[2,1-b:3,4-c']dipyridin-5-one, and 5H-cyclopenta]2,1-b:3,4-b']dipyridin-5-one can be prepared according to the method of Kloc, Michowski and Szulc. J. prakt. chemie, 319, 95q(1977). These ketones in accordance with Method I are derivatized into the spiro-hydantoin products. Wolff-Kishner reduction or reduction according to Method VIII of the aforementioned ketones yields the corresponding diazafluorene substrates such as 5H-cyclopenta[2,1-b:4,3-b']dipyridine. These diazafluorene substrates are derivatized according to Methods II-IV to yield the corresponding spiro-thiazolidinedione, spiro-oxazolidinedione and spiro-succinimide derivatives.
PREPARATION K
Synthetic substrates 8H-indeno[2,1-b]furan-8-one and 8H-indeno[2,1-b]furan and their derivatives are prepared in accordance with the following. Substituted and unsubstituted 3-arylfuran-2-carboxylic acids are prepared according to a general procedure of Burgess, J. Org. Chem., 21, 102 (1956), wherein, 4,5-dimethoxy-1-phenyl-2-butanone and related 2' to 4' substituted phenyl analogs (e.g., 4,4-dimethoxy-1-(4'-fluorophenyl)-2-butanone, prepared according to the general procedure of Royals and Brannoch, J. Amer. Chem. Soc., 75, 2050 (1953)) are converted into 3-phenylfuran-2-carboxylic acid methyl ester (e.g., 3'-(4'-fluorophenylfuran-2-carboxylic acid methyl ester) by the Darzens glycidic ester condensation (Darzens, Compt. Rend., 139, 1214 (1904)). This rearrangement of the glycidic ester yields the furoic ester. The furoic ester can be hydrolyzed in alkaline methanolic solution to yield, for example, 3-4'-fluorophenyl)-furan-2-carboxylic acid. The furoic acid product can be cyclized via the aroyl chloride in the presence of stannic chloride or aluminum chloride to yield the ketone, e.g., 6-fluoro-8H-indeno [2,1b]furan -8one. This ketone can be derivatized in accordance with Method V. Hydantoin derivatization (Method I) yields the spiro-hydantoin, e.g., spiro-(6-fluoro-8H-indeno[2,1-b]furan-8,4'-imidazolidine)-2',5'-dione. Reduction according to methods cited in Method VIII yields the corresponding 8H-indeno[2,1-b]furan derivative which can be derivatized in accordance with methods II, III and IV into the corresponding spiro-thiazolidinedion, spiro-oxazolidinedione and spiro-succinimide. Furthermore, the spiro-derivatives may be further derivatized according to Method VI.
PREPARATION l
Synthetic substrates 4H-indeno[1,2-b]furan-4-one and 4H-indeno[1,2-b]furan and their substituted analogs are prepared from the corresponding substituted and unsubstituted 2-arylfuran-3-carboxylic acids which are prepared according to a general procedure of Johnson, J. Chem. Soc., 1946. 895. The procedure involves the condensation of 1,2-dichlorodiethyl ether with aroylacetic esters, such as ethyl benzoylacetate (Aldrich Chemical, Inc.), in the presence of 10% ammonium hydroxide, yields a mixture of the 2-arylfuran-3-carboxylic ester and 2-arylpyrrole-3-carboxylic ester (which can be used to prepare the corresponding 4H-indeno[1,2-b]pyrrole-4-one) which are separated by fractionation. Saponfication (10% KOH in 50% methanol) of the furan ester, acidification and isolation yields the corresponding 2-arylfuran-3-carboxylic acid. Treatment with phosphorus pentachloride followed by stannic chloride effects the Friedel-Crafts cyclization to the ketone. Alternatively, thionyl chloride may be employed to prepare the acyl chloride followed by aluminum trichloride or stannic chloride as the Friedel-Crafts catalyst in a solvent such as methylene chloride to yield the process is summarized by this example: ##STR61## Then according to Method I, the spiro-hydantoin derivative is prepared, e.g., spiro-(6-chloro-4H-indeno[1,2-b]furan-4,4'-imidazolidine'2',5'-dione.
Analogous to earlier preparations, the ketone can be reduced according to Method VIII (Wolff-Kishner reduction) to yield the corresponding 4H-indeno[1,2-b]furan. This heterocycle can be derivatized according to Method V. The derivatized or underivatized 4H-indeno[1,2-b]furan according to Method II, III and IV is derivatized to the corresponding spiro-thiazolidinedione, spiro-oxazolidinedione and spiro-succinimide respectively.
These spiral derivatives may be further derivatized in accordance with Method VI.
PREPARATION M
Synthesis substrates 9H-pyrrolol[1,2-a]indole and H-pyrrolol[1,2-a] indole -9-one and their derivatives are prepared in accordance with the general methods of Josey and Jenner, J. Org. Chem., 27 (1962) 2466 and Mazzola et al., J. Org. Chem., 32 (1967) 486. The process involves condensation of a substituted or unsubstituted methyl anthranilate (Aldrich Chemical, Inc.) with 2,5-dimethoxytetrahydrofuran (Aldrich Chemical, Inc.) in glacial acetic acid. Ester hydrolysis of the resulting 1-(2-methoxycarbonylphenyl)pyrrole with 10-15% potassium or sodium hydroxide in aqueous alcohol (e.g., 50% methanol) yields after acidification and subsequent work-up yields the corresponding 1-(2-carboxyphenyl)pyrrole. This acid is then converted into the corresponding acyl chloride to facilitate a Friedel-Crafts cyclization to the ketone. The preferred method of preparing the acyl chloride is with phosphorus pentachloride followed with stannic chloride as the Friedel-Crafts catalyst to cyclize the acyl chloride to the desired ketone. ##STR62## Wolf-Kishner reduction see also Method VIII, via the semicarbazones of the ketone yields the corresponding 9H-pyrrolol[1,2-a]indole heterocycle.
The resulting ketone, such as 9H-pyrrolol[1,2-a]indole-9-one, is converted into the corresponding spiro-hydantoin according to Method I, see Example XV. The resulting spiro-hydantoin can be further derivatized in accordance with Method VI. Alternatively, the ketone may be derivatized according to Method V prior to spiro-hydantoin derivatization.
Similarly, 9H-pyrrolol[1,2-a]indole or its derivatives may be derivatized according to Method V. The derivatized or underivatized heterocycle then may be further derivatized according to Method II, III or IV to yield the corresponding spiro-thiazolidinedione, spiro-oxazolidinedione or spiro-succinimide respectively. These spiro-derivatives in turn may be derivatized in accordance with Method VI.
PREPARATION N
Synthesis substrates 4H-indeno[2,3-c]-1,2,5-thiadizol-4-one and 4H-indeno[2,3-c]-1,2,5-thiadizole and their derivatives are prepared in accordance with the procedure of Mataka et al., Synthesis, 1979, 524 and Mataka et al., J. Hetero. Chem., 17 (1980) 1681. The process involves reacting tetranitrogentetrasulfide with 1,3-dihydro-2H-indeno-2-one (Aldrich Chemical, Inc.) in toluene at reflux yields: ##STR63## Alternatively, 5-fluoro-1,3-dihydro-2H-indeno-2-one (Flammang et al., Eur. J. Med. Chem., 11 (1976) 83), 4-chloro-1,3-dihydro-2H-indeno-2-one (CA80:146166a) and 5chloro-1,3-dihydro-2H-indeno-2-one (Olivier et al., Bull./ Soc. Chem. Fr., 11 (1973) 3096) can similiar be rated with tetranitrogentetrasulfide to yield the corresponding substituted indenthiadiazole heterocycles. These heterocycles may be further derivitized in accordance with Method V and according to Methods II, III and IV derivatized into the corresponding spiro-thiazolidinedione, spiro-oxazolidinedione and spiro-succinimides respectively. These spiro derivatives in turn may be further derivatized according to Method VI. oxidation of the 4H-indeno[2,3-c]-1,2,5-thiadiazole in accordance with Method VII yields the ketone which may be derivatized in accordance with Method I to yield the corresponding spiro-hydantoin, e.g., spiro(4H-indeno[2,3-c]-1,2,5-thiadiazole-4,4'-imidazolidine)-2',5'-dione. This spriro hydantoin in turn may be derivatized further in accordance with Method VI.
PREPARATION O
The triheterocyclic substrates thieno[2,3-b]pyrrolizine and thieno [2,3-b]bipyrrolizin-4-one; thieno [3,2-b]pyrrolizine and thieno[3,2-b]pyrrolizine and thieno [3,2-b]pyrrolizin-4-one are prepared exactly according to Rault et al., Heterocycles, 20 (1983) 477. The process involves the cyclization in boiling phosphoryl chloride of amide derivatives of 2-(1-pyrrolyl)-3-thienylcarboxylic acid and 3-(1-pyrrolyl)-2-thienylcarboxylic acid to yield thieno [2,3-b]pyrrolizin-4-one and thieno[3,2-b]pyrrolizin-4-one respectively. These ketones in accordance with Method I can be derivatized to the corresponding spiro-hydantoins: spiro-(thieno [3,2-b]pyrrolizin-4,4'-imidazolidine)-2',5'-dione and spiro-(thieno[3,2-b]pyrrolizin-4,4'-imidaz [3,2-b]pyrrolizin-4,4'-imidazolidine)-2',5'-dione. Both thieno [2,3-b]pyrrolizin-4one and thieno[3,2-b]pyrrolizin-4-one can be reduced with 1.75 equivalents of lithium aluminum hydride in the presence of 3.5 equivalents aluminum chloride to yield the corresponding 4 H-thieno-pyrrolizines quantitatively. The resulting thieno[2,3-b]pyrrolizine and [2,3-b]pyrrolizine can be derivatived according to Methods II, III and IV into the corresponding spiro-thiazolidinediones, spiro-oxazolidinediones and spiro-succinimides, such as spiro-(thieno[3,2-b]pyrrolizin-4,5'-thiazolidine)2',4'-dione, spiro-(thieno[2,3-b]pyrrolizin4,5'-oxazolidine)-2',4'-dione and spiro-(thieno[3,2-b]pyrrolizin-4,3'-succinimide).
PREPARATION P
In an analogous manner to the preceding, the following starting materials may be derivatized in accordance with Methods I, II, III, IV, V, VII, and VIII. Resulting spiro-derivative products may be further derivatized in agreement with Method VI.
a) 1- and 2- substituted -1H-indeno[1,2c]pyrazol-4-ones ##STR64## wherein R 1 =H or lower alkyl and R 2 =lower alkyl or lower cycloakyl, are prepared according to Lemke and Sawney, J. Heterocyclic Chem. 19 (1982 )1335 and Mosher and Soader. Heterocychic Chem., 8 (1971) 855.
b) 3-alkyl-4H-indeno[1,2-c]isoxazol-4-ones ##STR65## wherein R 2 =lower alkyl (preferably methy), are prepared according to Lemke et al., J. Heterocyclic Chem., 19 (1982) 363.
c) 3-alkyl-4H-indeno[1,2-c]isoxazol-4-ones ##STR66## wherein R 2 =lower alkyl (preferably methyl), are prepared according to Lemke and Martin, J. Heterocyclic Chem., 19 (1982) 1105.
d) 3-methyl-1uns/H/ -pyrazolo[3',4':3,4]cyclopenta[1,2-b]pyridin-4one and 3-methyl-1H-pyrazolo[3',4':3,4]cyclopenta [2,1-c]pyridin-4one ##STR67## respectively are prepared according to Mosher and Banks, J. Heterocyclic Chem., 8 (1972) 1005.
e) The following indenopyrimidinone ##STR68## is prepared according to CA90:38958q.
f) 5H-indeno[1,2-c]pyridazine and 3-methyl-5H-indeno[1,2-c] pyridazine ##STR69## is prepared according to Loriga et al., Farmaco, Ed. Sci., 34 (1979) 72.
After spiro-derivatization the corresponding spiro-hydantoin, spiro-thiazolidinedione, spiro-oxazolidinedione and spiro-succinimide products are obtained.
PREPARATION Q
Synthesis substrate, 4H-indeno[2,3-c]oxadiazo-4-one and 4H-indeno-[2,3-c]-1,2,5-oxadiazole and their derivatives are prepared in accordance with the following process (see Korte and Storiko, Chemische Berichte, 94 (1961) 1956). The starting material 4-oximino-3-phenyl-isoxazole is prepared according to Ber. dtsch. Chem. Ges., 24 (1891) 140, see also Hantzwch and Heilbron, Chemische Berichte, 43 (1910) 68: ##STR70## and hydrolyzed with water and treated with sodium carbonate to effect a rearrangement according to Korte, ibid. ##STR71## The resulting acid is cyclized by stepwise treatment with phosphorus pentachoride in methylene chloride followed by Friedel-Crafts cyclization catalyzed by stannic chloride. The resulting ketone is derivatized in accordance with Method I to yield the spiro-hydantoin ##STR72## which may be further derivatized according to Method VI. The ketone may be reduced according to Method VIII (Wolff-Kishner reduction) and further derivatized in accordance with Method V. The substituted heterocycle may be oxidized back to the ketone in accordance to Method VII and then derivitized to the spiro-hydantoin. Alternately the heterocycle may be derivatized in accordance with methods II, III and IV to the corresponding spiro-thiazolidinedione, spiro-oxazolindinedione and spiro-succinimide. These may be further derivatized in accordance with Method VI.
EXAMPLE I
9-hydroxy-9H-fluorene-9-carboxylic acid methyl ester (1) ##STR73## 9Hydroxy-9H-fluorene-9-carboxylic acid (Aldrich Chemical, Inc.) (20.0 g, 88.4 mmol) was added to 100 mL methanol saturated with hydrogen chloride and mixture was stirred at reflux for 4 h. The crystaline material obtained on cooling was collected by filtration and washed with cold 1:1 ethyl acetate/hexane to provide after drying (1), 15.8 g (74%).
Spiro-(9H-fluorene-9.5'-oxazolidine)-2',4'-dione (2) ##STR74## To a stirred solution of sodium (190 mg, 8.26 mmol) in 20 mL absolute ethanol was added urea (500 mg, 8.26 mmol) and 9-hydroxy-9H-fluorene-9-carboxylic acid methyl ester (1) (2.00 g, 8.26 mmol). The mixture was stirred at reflux under nitrogen for 15 h. After cooling to room temperature, the reaction mixture was poured into 100 mL water and acidified with 2N aqueous hydrochloric acid to precipitate the product which was collected by filtration, washed with water, and dried to provide 1.5 g crude (2). Recrystallization from ethyl acetate gave 260 mg (b 12%): m.p. 225°-257° C. A second crop, 620 mg (30%), was obtained by evaporation of the mother liquor followed by recrystallization from ethyl acetate/hexane. M/e + . 251. For the preparation of oxazolidinediones from α-hydroxy esters using urea and sodium ethoxide, see: Stoughton, J. Am. Chem. Soc. (1941) 63, 2376.
EXAMPLE II
2-Fluoro-9H-fluorene-9-carboxylic acid (3) ##STR75## Under nitrogen atmosphere, n-butyllithium (1.25 eq, 0.170 mK, 65 mL of a 2.6M hexane solution) was added dropwise over 30 min. to a stirred .5° C. solution of 2-fluorofluorene (prepared according to U.S. Application Ser. Nos. 368,630 and 368,631) (25.0 g, 0.136 mmol) in 500 mL dry THF. After an additional 35 min. a flow of dry carbon dioxide gas into the solution was commenced and continued for 15 min. at 0°-15° C. and 45 min. at room temperature. 2N aqueous hydrochloric acid (200 mL) was added, and the mixture was transferred to a separatory funnel. The aqueous layer was separated and extracted 1×100 mL ethyl acetate. the combined organic phases were washed 1×100 mL brine, dried (MgSO 4 ), and evaporated to leave a dark residue which was triturated with 250 mL hexane to leave 16.6 g crude acid. Recrystallation from acetonitrile gave 10.2 g of the acid (3). A second crop of 2.0 g was obtained from the concentrated filtrate. Chromatography of the filtrate and the concentrated hexane extract on silica gel using 10-50% acetate/hexane provided another 2.8 g. Total yield: 15.0 g (48%).
2-Fluoro-9H-fluorene-9-carboxylic acid methyl ester (4) ##STR76## Acetyl chloride (33 mL) was added dropwise to a stirred, ice-cold solution of 2-fluoro-9H-fluorene-9-carboxylic acid (3) (16.7 g, 73.2 mmol) in 200 mL methanol and the solution was then refluxed for 4 h. Solvent removal left the crude product which was recrystallized from methanol to provide (4), 14.1 g (79%): m.p. 90°-92° C. (from hexane). For the preparation of 9H-fluorene-9-carboxylic acid from fluorene using phenyllithium and esterification using methanolic hydrogen chloride see: Bavin, Anal. Chem. (1960) 32, 554.
2-Fluoro-9-hydroxy-9H-fluorene-9-carboxylic acid methyl ester (5) ##STR77## To a stirred solution of sodium (1.25 eq, 22.3 mmol, 510 mg) in 100 mL methanol was added 2-fluoro-9H-fluorene-9-carboxylic acid methyl ester (4) (4.33 g, 17.9 mmol). After 15 min. a flow of dry oxygen into the solution was commenced and continued for 1 h. Some of a solution of sodium bisulfite (24.5 g) in 300 mL water was added until the reaction became cloudy. The mixture was then poured into the remaining bisulfite solution. After cooling in ice, the solid that separated was collected by fitration, washed well with water, and dried to provide (5), 4.05 g (88%).
Spiro-(2-fluoro-9H-fluorene-9,5'-oxazolidine)-2', 4'-dione (6) ##STR78## To a stirred solution of sodium (1.03 eq, 130 mg) in 13 mL absolute ethanol was added 2-fluoro-9-hydroxy-9H-fluorene-9-carboxylic acid methyl ester (5) (1.42 g, 5.5 mmol) and urea (5.5 mmol, 330 mg). The mixture was then refluxed 15 h. After cooling to room temperature, the mixture was poured into 65 mL water and acidified with 2N aqueous hydrochloric acid. The yellow solid that separated was collected, washed with water, and dried to give 1.19 g crude material. Chromatrography on silica gel using 1-100% methanol/chloroform gave pure (6), 580 mg (39%), m/o + . 269.
EXAMPLE III
9-Chloro-9H-fluorene-9-carboxylic acid methyl ester (7) ##STR79## A mixture of 9-hydroxy-9H-fluorene-9-carboxylic acid methyl ester (1) (5.00 g, 20.8 mmol) and 50 mL thionyl chloride was heated at reflux for 3 h. The thionyl chloride was removed on the rotavapor to leave a solid residue which was redissolved in 50 mL benzene and then evaporated to remove traces of thionyl chloride. The resulting material was recrystallized from acetic acid to give (7), 3.23 g (60%): m.p. 111°-114° C. An additional 960 mg (18%) of product was obtained by chromatography of the reduced filtrate on silica gel using 10% ethyl acetate/hexane.
Spiro-[9H-fluorene-9,5'-(2'-amino-4'-thiazolone)] (8) ##STR80## A mixture of 9-chloro-9H-fluorene-9-carboxylic acid methyl ester (7) (4.21 g, 16.3 mmol) and thiourea (1.24 g, 16.3 mmol) in 150 mL dioxane was heated at reflux for 10 h. After cooling in room temperature, the fine white solid present was collected by filtration and washed with dioxane provided (8), 1.31 g (30%). The gummy residue which remained in the flask was chromatographed on silica gel using 10-20% methanol/chloroform to give another 220 mg (5%) of (7): m.p. 320°-322° C. (dec). For the preparation of 2-imino-4-thiazolidinones from α-halo acid halides using thiourea in dioxanes, see: Skinner, J. Org. Chem. (1961) 26, 1450.
Spiro-(9H-fluorene-9, 5'-thiazolidine)-2',4'-dione (9) ##STR81## A mixture of spiro-[9H-fluorene-9,5'-(2'-amino-4'-thiazolone)] (8) (1.19 g, 4.47 mmol), 24 mL methanol, and 24 mL concentrated hydrochloric acid was refluxed 4 h. The reaction mixture was cooled in ice and the white precipitate was collected filtration, washed with water, and dried to provide 640 mg crude (9). Recrystallization from acetonitrile gave 490 mg (41%): m. p. 253°-255° C. A second drop of 80 mg (7%) was obtained from the mother liquor. Calc. %C 67.40, %H 3.39; %N 5.24: meas. %C 67.46, %H 3.34, N 5.32. For the hydrolysis of 2-amino-4-thaizolones to thiazolidinediones using methanolic hydrogen chloride, see: Koltai, Tetrahedron (1973) 29, 2781.
EXAMPLE IV
b 9-Chloro-2-fluoro-9H-fluorene-9carboxylic acid methyl ester (10) ##STR82## A mixture of 2-fluoro-9-hydroxy-9H-fluorene-9-carboxylic acid methyl ester (5) (4.00 g, 15.5 mmol) and 50 mL thionyl chloride was refluxed 3 h. After the thionyl chloride was removed on the rovapor, the material was redissolved in 50 mL benzene and the benzene then evaporated to remove trace thionyl chloride. The crude product, 4.3 g (100%), was used without further purification.
Spiro-[2-fluoro-9H-fluorene-9,5'-(2'-amino-4'-thiazolone)] (11) ##STR83## A mixture of 9-chloro-2-fluoro-9H-fluorene-9-carboxylic acid methyl ester (10) (4.31 g, 15.6 mmol) and thiourea (1.1 eq, 17.2 mmol, 1.31 g) in 140 mL dioxane was refluxed for 10 h. After cooling to room temperature, the fine white precipitate was collected by filtration and washed with water providing (11), 1.28 g (29%). An additional 1.3 g (29%) of (11) was obtained by chromatography of the reduced filtrate on silica gel using 5-50% methanol/chloroform.
Spiro-(2-fluoro-9H-fluorene-9,5'-thiazolidine)-2',4'-dione (12) ##STR84## A mixture of spiro-[2-fluoro-9H-fluorene-9,5'-(2'-amino-4'-thiazolone)] (11) (1.85 g, 6.51 mmol), 35 mL methanol, and 35 mL concentrated hydrochloric acid was heated at reflux for p6 h. After cooling to room temperature, the white precipitate was collected by filtration and washed with water to provide 1.22 g of crude (12). Recrystallization from ethanol provided three crops totaling 870 mg (47%): m.p. 272°-276° C. (dec). m/e + . 285.
EXAMPLE V
2,7-Difluoro-9H-fluorene-9-carboxylic acid (13) ##STR85##
To a stirred, room temperature solution of 2,7-difluorofluorene (prepared according to U.S. Application Nos. 368.630 and 368,631) (10.0 g, 49.5 mmol in 75 mL dry diethyl ether under a nitrogen atmosphere was added over 15 min n-butyllithium (1.25 eq, 61.9 mmol, 24 mL of a 2.6M hexane solution). The solution was refluxed 30 min., cooled to room temperature, and then quickly poured onto an ether slurry of a large excess of powdered dry ice. After the dry ice evaporated, the mixture was transferred to a separatory funnel along with 100 mL 2N aqueous hydrochloric acid and 50 mL ethyl acetate. After shaking well, the organic layer was separated and evaporated to dryness. The residue was extracted 2×100 mL warm (50° C.) 2% aqueous sodium hydroxide and then the extract was acidified with concentrated hydrochloric acid to precipitate the impure acid which was collected by filtration and washed with water. This material was dissolved in 50% ethyl acetate/hexane and passed through a 50 mm×7 silica gel column using the same solvent to remove highly colored, baseline impurities and to provide (13) sufficiently pure to be used in the next step, 7.91 g (65%): m.p. 128°-130° C. (from benzene).
2,7-Difluoro-9H-fluorene-9-carboxylic acid methyl ester (14) ##STR86## Acetyl chloride (13 mL) was added dropwise to a stirred, ice-cold solution of 2,7-difluoro-9H-fluorene-9-carboxylic acid (14) (6.90 g, 28 mmol) in 77 mL methanol. The mixture was then headed at reflux for 4 h. The product which crystallized upon cooling in ice was collected by filtration and washed with cold methanol to provide (14), 5.15 g (71%): m.p. 161 -163° C. (from toluene).
2,7-Difluoro-9-hyroxy-9H-fluorene-9-carboxylic acid methyl ester (15) ##STR87## 2,7-Difluoro-9H-fluorene-9-carboxylic acid methyl ester (14) (4.73 g, 18.2 mmol) was added to a solution of sodium (1.25 eq, 22.7 mmol, 520 mg) in 100 mL methanol. After 15 min., a flow of dry oxygen into the solution as commenced and continued for 1 h. Some of a solution of 24.5 g sodium bisulfite in 800 mL water was added until the mixture turned cloudy and then the whole was poured into the remaining bisulfite solution. The solid was collected by filtration, washed with water, and dried to provide (15), 4.68 g (93%): m.p. 174°-176° C. (from benzene).
9-Chloro-2,7-difluoro-9H-fluorene-9-carboxylic acid methyl ester (16) ##STR88## A mixture of 2,7-difluoro-9-hydroxy-9H-fluorene-9-carboxylic acid methyl ester (15) (3.63 g, 13.1 mmol) and 50 mL thionyl chloride was heated at reflux for 4 h. The reaction mixture was then diluted with 300 mL benzene and evaporated to leave (16), 3.7 g (96%), which was used in the next step without further purification: m.p. 140°-142° C. (from acetonitrile).
Spiro-[2,7-difluoro-9H-fluorene-9,5'-(2'-amino-4'-thaizolone)]](17) ##STR89## A mixture of 9-chloro-2,7-difluoro-9H-fluoroene-9-carboxylic acid methyl ester (16) (3.56 g, 12. 1mmol) and thiourea (1.1 eq, 13.3 mmol, 1.01 g) in 110 mL dry dioxane was heated at reflux for 12 h. After cooling to room temperature and in ice, the white precipitate was collected by filtration, washed with dioxane, and dried to provide (17), 490 mg (13%). The concentrated filtrate an the gummy residue which remained in the flask were individually chromatographed on silica gel using 5-20% methanol/chloroform to provide another 1.00 g (27%) product: m.p.>300° C.
Spiro-(2,7-difluoro-9e,uns/H/ -fluorene-9,5'-thiazolidine)-2',4'-dione (18) ##STR90## A mixture of spiro-[2,7-9H-fluorene-(2'-amino-4'-thaizolone)] (17) (1.17 g, 3.87 mmol), 21 mL methanol, and 21 mL concentrated hydrochloric acid was refluxed for 6 h. The reaction mixture was cooled in ice and the off-white precipitate was collected by filtration, washed with water, and dried to provide 900 mg crude (18). This material was chromatographed on silica gel using 5-10% methanol/chloroform to yield pure (18), 530 mg (45%): m. p. 260°-263° C.(dec). Calc. %C 59.40, %H 2.33, %N 4.62: meas. %C 59.47, %H 2.42, %N 4.64.
EXAMPLE VI
Spiro-(9H-fluoren-9,3'-succinimide) (20) ##STR91## 9H-fluoren-9-carboxylic acid methyl ester (19), which was prepared by refluxing 9H-fluoren-9-carboxylic acid (Aldrich Chemical, Inc.) in HCl/MeOH, (10.0 g, 44.6 mmol) was added to a solution of sodium (1.2 eq, 53.5 mmol, 1.23 g) in 100 mL methanol. After 15 min., 2-chloroacetamide (1.1 eq, 49.1 mmol, 4.59 g) was added and the mixture was allowed to stir at room temperature under nitrogen for two (2) days. The reaction mixture was poured into 400 mL of cold 2.5% w/v aqueous sodium hydroxide and the insoluble material was removed by filtration. The filtration was chilled and acidified with concentrated hydrochloric acid to precipitate the spiro-succinimide which was collected and air dried to provide 6.7 g (60%). Recrystallization from methanol gave purified (20), 4.28 g (39%). m.p. 237°-239° C. Calc. %C 77.09, %H 4.45, %N 5.62: meas. %C 77.17 , %H 4.55, %N 5.58.
EXAMPLE VII
Spiro-(2-flnoro-9H-flnoren-9,3'-succinimide) (21) ##STR92## The spiro-succinimide (21), m.p. 248°-250° C., was prepared analogous to Example VI except from (4) in 25% yield. Calc. % C71.90, % H 3.77, % N 5.24: meas. % C 71.97, % H 3.87, % N 5.33
EXAMPLE VIII
5H-Indeno[1,2-b]pyridine-5-carboxylic acid methol ester (22) ##STR93## Under a nitrogen atmosphere, n-butyllithium (1.2 eq, 105 mmol, 65 mL of a 2.6M hexane solution) was added dropwise over a 30 min. period to a stirred 0°-5° C. solution of 4-azafluorene (14.65 g, 87.6 mmol) in 150 mL dry tetrahydrofuran (dried and distilled from LAH). After 1 h 20 min. the reaction mixture was poured into an ether slurry containing a large excess of dry ice. Solvents were allowed to evaporate overnight. The residue was suspended in 300 mL methanol, chilled and 60 mL acetyl chloride was added dropwise over 45 min. and the mixture stirred for 22 h at room temperature. Purification by chromatography (30% ethyl acetate/hexanes on silica gel) and solvent evaporation yields 16.3 g (83%) of (22).
5-Hydroxy-5H-indeno[1,2-b]pyridine-5-carboxylic acid methyl ester (23) ##STR94##
To a stirred solution of sodium (1.1 eq, 60.1 mmol. 1.38 g) in 150 mL dry methanol was added a solution of 5-hydroxy-5H-indeno[1,2-b]pyridine-5-carboxylic acid methol ester (22) (12.3 g, 54.6 mmol) in 50 mL dry methanol. The solution was cooled in ice and, after 15 min., a flow of dry oxygen was begun and continued for 1 h. Then the reaction mixture was poured into a solution of 12 g sodium bisulfite in 200 mL water. After 30 min. the mixture was evaporated to dryness. The resulting solid was triturated with 2×100 mL acetone and filtered. The remaining inorganic salts were removed by filtration. The filtrate was evaporated to yield 24.2 g wet pink solid of (23). Drying in vacuo over phosphorus pentaoxide yielded 12.5 g crude (23). Recrystallization from ethyl acetate yielded two crops 8.06 g (61%) and 2.54 g (19%) of (23).
5-Chloro-5H-indeno[1,2-b]pyridine-5-carboxylic acid methyl ester (24) ##STR95## A mixture of 5-hydroxy-5H-indeno[1,2-b]pyridine-5-carboxylic acid methyl ester (23) (8.06 g, 33.4 mmol) in 200 mL thionyl chloride was heated at reflux for 4 h. The thionyl chloride was removed on the rotavapor to leave a residue which was partitioned between water and chloroform and neutralized with saturated sodium bicarbonate. After further extractions with chloroform the combined chloroform extracts were dried over magnesium sulfate and evaporated to yield 7.87 g (91%) of (24).
Spiro-[5H-indeno[1,2-b]pyridine-5,5'-(2'-amino-4'-thiazolone)](25) ##STR96## A mixture of 5-chloro-5H-indeno[1,2-b]pyridine-5-carboxylic acid methyl ester (24) (7.87 g, 30.4 mmol), thiourea (1.2 eq, 36.4 mmol, 2.77 g) and sodium acetate (1.1 eq, 33.4 mol, 2.74 g) in 140 mL glacial acetic acid was refluxed for 40 min. Then 100 mL water was added and the pH was adjusted to 6.7 with hydrochloric acid. The aqueous portion was decanted from the precipitate, followed by additional 50 mL water wash. The dried residue was treated with ethyl acetate and the resulting crystalline solid was collected by filtration and dried to yield 1.81 g (32%) of (25).
Spiro-(5H-indeno[1,2-b]pyridine-5,5'-thiazolidine)-2',4'-dione (26) ##STR97## A mixture of spiro-[5H-indeno[1,2-b]pyridine-5,5'-(2'-amino-4'-thiazolone)] (25) (1.00 g, 3.74 mmol) was stirred at reflux in a solution of 100 mL methanol and concentrated hydrochloric acid (1:1) for 2 h. The mixture was then concentrated to approximately 10 mL with heat and reduced pressure, chilled on ice and neutralized with sodium hydroxide solution. The resulting precipitate was collected by filtration and washed with water. Purification of the dried precipitate by chromatography (silica gel using 2.5-7% methanol/chloroform) yielded a product after solvent evaporation, 400 mg. Recrystallization of the residue from ethanol yielded crystalline (26). m/e + .268. IR strong bands at 1700 and 1745 cm -1 .
EXAMPLE IX
Spiro-(5H-indeno[1,2b]pyridine-5,3'-succinimide) (27) ##STR98##
The ester (22) (4.00 g, 17.8 mmol) was added all at once to a stirred, room temperature solution of sodium methoxide in methanol (sodium metal, 1.2 eq. 21.3 mmol, 490 mg and 40 mL dry methanol). After 15 min., chloroacetamide (1.1 eq, 19.5 mmol, 1.83 g) was added and the mixture was left to stir at room temperature under nitrogen. After two days the reaction mixture was poured into 100 mL 1N sodium hydroxide, cooled in ice and the pH was adjusted with concentrated hydrochloric acid to pH 7. The precipitated solid was collected by filtration and washed with cold water. The dried solid (2.02 g) was recrystallized from ethyl acetate with charcoal treatment to yield 1.03 g (23%) crystalline (27). m.p. 245°-246° C. Calc. % C 71.99, % H 4.03, % N 11.20: meas. % C 71.85, % H 4.14, % N 11.17.
EXAMPLE X
5H-Indeno[1,2-b]pyridin-5-one (28) ##STR99## See general oxidation method of Sprinzak, J. Am. Chem. Soc., 80 (1958) 5449. 4-Azafluorene (5.0 g, 30 mmol) was dissolved in 50 mL anhydrous pyridine containing in solution 2 mL Triton B solution (prepared by evaporating 5 mL of 40% Triton B in methanol (Aldrich Chemical, Inc.) and 5 mL pyridine with heat and reduced pressure followed by q.s. to 10 mL with pyridine). Then air was continuously bubbled through the solution with stirring. An addition of 2 mL Triton B solution was made twice more at two-hour intervals. After six hours the reaction mixture was evaporated to dryness. The residue was triturated in 30 mL water and extracted four times with ethyl acetate (total volume 200 mL). The combined ethyl acetate extracts were dried over anhydrous sodium sulfate. After filtration and evaporation, the residue was chromatographed (silica gel and chloroform) to yield after evaporation of the solvent 4.5 g (83%) of (28). m.p. 132°-136° C. (reported 142° C.).
Spiro-(5H-Indeno[1,2-b]pyridine-5,4'-imidazolidine)-2',5'-dione (29) ##STR100## 5H-Indeno[1,2-b]pyridine-5-one (4.0 g, 22 mmol) was mixed with potassium cyanide (1.6 g, 24 mmol) and ammonium carbonate (5.3 g, 55 mmol) in 90% ethanol (75 mL) in a pressure reactor and heated at 105° C. for 40 hr. The mixture was poured into 300 mL of water, acidified with conc. HCl (pH 1), and filtered. The filtrate was neutralized and the solid which formed collected by filtration, washed with water, and dried to yield 4.5 g. This solid was crystallized from ethyl acetate to yield 3.2 g of product. (This material was no longer soluble in ethyl acetate after the first crystallization). m/e + .251.
EXAMPLE II
Spiro-(7-nitro-indeno[1,2-b]pyridin-5,4'-imidazolidine)-2',5'-dione (30) ##STR101##
Spiro-(indeno[1,2-b]pyridine-5,4'-imidazolidine)-2',5'-dione (29) (1.0 g, 4 mmol) was added to cold concentrated sulfuric acid (10 mL) and stirred in an ice bath as concentrated nitric acid was added dropwise over about 10 min. The mixture was allowed to warm to room temperature and stirred overnight; the resulting solution was poured onto ice and the solution neutralized with concentrated aqueous sodium hydroxide. The solid which formed was collected by filtration, washed with a small volume of water, and dried. The product was dissolved in warm water 930 mL) by the addition of sodium hydroxide solution, treated with Norite decoloring charcoal, filtered through a celite bed and the bed washed with a small volume of warm dilate base. The combined filtrate and wash were neutralized with hydrochloric acid to yield a solid which was collected by filtration, washed with water and dried to yield 0.76 g of (30). Calc. % C 56.76, % H 2.72, % N 18.91: meas. % C 56.59, % H 2.83, % N 18.87. m/e + .296.
EXAMPLE III
Spiro-(7-bromo-indeno[1,2-b]pyridine-5,4'-imidazolidine)-2',5'-dione (31) ##STR102## Spiro-(indeno[1,2-b]pyridin-5,4'-imidazolidine)-2',5'-dione (29) (1.0 g, 4 mL) was dissolved in cold 70% sulfuric acid (50 mL). The solution was heated to 50° C., and N-bromosuccinimide (0.78 g, 4.3 mmol) was added in small portions with stirring. After stirring at 50° C. for 2 h, the reaction was poured onto ice, and the solution was neutralized with concentrated aqueous sodium hydroxide. The solid which formed was collected by filtration and washed with water. The sample was dissolved in 30 mL of warm water by addition of aqueous sodium hydroxide then treated with Norite, filtered through a celite bed and washed with warm dilute base, and the combined filtrate and wash were acidified with hydrochloric acid (to pH 6). The solid was collected by filtration, washed with water, and dried to yield 0.88 g of (31). m/e + .329.
EXAMPLE XIII
4H-indeno[1,2-bithiophen-4-one (35) ##STR103## To methyl anthranilate (90.0 g, 77 mL, 595 mmol, 1.0 eq) was added hydrochloric acid (120 mL of conc., 1450 mmol, 2.4 eq diluted with 100 mL distilled water). The resulting mixture of solid and liquid was heated to reflux with stirring while protected from light. The hot clear solution was cooled to 5° C. whereupon a solid precipitated. To this stirred mixture was added sodium nitrite solution (41.09 g, 596 mmol, 1.0 eq in 90 mL distilled water) at a rate to maintain the reaction temperature below 5° C. After 1.5 h fluoroboric acid (95 g, 48% in water) was added rapidly and the resulting suspension was stirred for an additional 30 min. at -10° to 0° C. The suspended solid was collected by filtration, washed with 100 mL cold water, 120 mL cold methanol and 500 mL ether. The resulting pink solid was dried in vacuo over concentrated sulfuric acid to yield 39.5 g of (32) as a pink solid (m.p. 93°-98° C. with decomposition, reported 102° C. with decomposition Org. Reactions 5, 219).
To a diazo salt (32) (39.5 g, 158 mmol, 1.0 eq) in thiophene (75 mL) stirred suspension was dropwise added during 1 h a solution consisting of 3,5-dimethylpyrazole (15.80 g, 164 mmol, 1.04 eq) and hydroquinone (1.91 g, 17 mmol, 0.11 eq) in 125 mL thiophene at 0° C. After 2.5 h additional stirring at 0°-5° C. the reaction was stirred overnight at ambient temperature (see J. Org. chem., 46 (1981) 3960). Evaporation with heat and reduced pressure yielded a brown semisolid. columan chromatography (silica gel, 1:9 to 1:4 ethyl ether/petroleum ether) yields 19.4 g. Distillation (bp 141°-160° C., 4 mmHg) yields 15.1 g of (33).
To 15.1 g of (33) was added methanolic potassium hydroxide (12.8 g KOH in 200 mL methanol) and the reaction mixture was refluxed for 4 h whereupon potassium hydroxide (2.5 g) was added. After 5 h total reflexing, the starting material (33) was completely hydrolyzed (silica gel. 40% Pet ether/ether). To the cooled mixture was added 250 mL water and the diluted mixture was extracted with 250 mL ethyl ether. The ether extract was back extracted with 150 mL 10% KOH. The combined aqueous fractions were cooled and acidified with concentrated hydrochloric acid to pH 2. The acidified slurry was then extracted with diethyl ether (3×200 mL), the ether extracts washed with brine (150 mL) then dried with anhydrous magnesium sulfate. After filtration and evaporation, 23.7 g tan solid resulted. m.p. 80° C. (reported m.p. 93°-94° C., J. Med. Chem., 9 (1966) 551). To the acid (13.7 g, 69.2 mmol, 1.0 eq) was added thionyl chloride (25.3 mL, 213 mmol, 3.1 eq) and the mixture was refluxed for 2 h. After cooling the reaction mixture was evaporated with reduced pressure and heat with 3×100 mL benzene additions to result in 15 g of (34) as a dark oil.
Under nitrogen, a stannic chloride solution (SnCl 4 , 9.1 g, 4.1 mL, 1.25 eq is 40 mL benzene) was added over 20 min. to a benzene (100 mL) solution of the acid chloride (34) (15 g, 69.2 mmol) at 0°-4° C. with mechanical stirring. After a total of 30 min. the reaction mixture was poured into 200 cc ice containing 100 mL 1N hydrochloric acid. (See J. Org. chem., 35 (1970) 872). Ethyl acetate extractions (600 mL) of the aqueous mixture yielded a dark organic extract. Washing the organic extract with 100 mL 100% sodium hydroxide, 100 mL water (2×) yielded an orange ethyl acetate extract which was dried over anhydrous magneisum sulfate. Filtration and evaporation yielded a dark residue. Column chromatography (silica gel. 1:9 ethyl ether/petroleum ether) yields a purified 4.5 g sample of orange (35). m.p. 99.5°-101.5° C. from hexane. (lit. 101° C. J. Org. Chem. 35 (1970) 872). Calc. % C 70.94, % H 3.25, % S 17.22: meas. % C 70.98, % H 3.33, % S 17.16.
Spiro-(4H-indeno[1,2-b]thiophen-4,4'-imidazolidine)-2',5'-dione (36) ##STR104##
To a glass-lined, high-pressure steel reaction vessel was added ketone (35) (373 mg, 2 mmol), potassium cyanide (406 mg, 5 mmol), ammonium carbonate (577 mg, 6 mmol) and ethanol (15 mL). The sealed vessel was heated at 110° C. for 24 h. The dark reaction mixture was poured into water and acidified with concentrated hydrochloric acid to pH 1. The resulting dark solid was collected by filtration and resolubilized in 10% sodium hydroxide (30 mL), treated with charcoal and filtered. The filtrate was acidified with concentrated hydrochloric acid. The resulting precipitate was collected by filtration and dried. The solid was dissolved in dimethylformamide, treated with Darco G-60 and filtered through a Celite pad. Dilution with water 3X volume) resulted in a precipitate which was collected by filtration. The collected solid was dissolved in 10% sodium hydroxide (3 mL), filtered, and the filtrate was acidified with conc. hydrochloric acid, the white precipitate collected by filtration, washed with water and dried at 105° C. to yield 110 mg of (36). m. p. 336°-8° C.
Calc. % C 60.92, % H 3.15, % N 10.96: meas. % C 60.83, % H 3.22, % N 10.97.
EXAMPLE XIV
8H-Indeno[2,1-b]thiophen-8-one (38) ##STR105##
Thionyl chloride (60.3 g, 37 mL, 500 mmol, 3.6 eq) was added at 250° C. to o-bromobenzoic acid (Aldrich Chemical, Inc.) (28.1 g, 140 mmol, 1.0 eq). After addition the reaction mixture was heated to 80° C. for 13 h. Evaporation with heat and reduced pressure partially reduced the volume. Then under nitrogen atmosphere 100 mL methylene chloride followed by 3-bromothiophene (Aldrich Chemical, Inc.) (22.8 g, 13.1 mL, 140 mmol, 1.0 eq) in 100 mL methylene chloride were added to acyl chloride intermediate. Then aluminum trichloride (23.9 g, 179 mmol, 1.3 eq) was added in small portions to the reaction mixture at 0° C. After addition, the reaction mixture was allowed to slowly reach room temperature. After 17 h the reaction was quenched by the slow addition of 150 mL 2N hydrochloric acid. Water (2×150 mL) and brine (100 ML) washing, drying over anhydrous magnesium sulfate, filtration and evaporation of the filtrate in vacuo yielded approximately 50 g of an oil of (37) which solidified in the freezer. IR 1645 cm -1 for diaryl ketone.
Diaryl ketone (37) (44 g, 480 mmol, 4 eq) and activated copper (prepared from aqueous copper sulfate, zinc dust, 5% hydrochloric acid) (30 g, 480 mmol, 4 eq) in 200 mL dimethylformamide were refluxed for 6.5 h. After the cooling the reaction mixture was filtered and 150 mL water added. The filtrate was extracted with ethyl ether (5×150 mL). The combined ether extracts were washed with 150 mL 1N hydrochloric acid, 150 mL water and 150 mL brine. Then the ether solution was dried over anhydrous magnesium sulfate, filtered and evaporated to yield a solid, 18.6 g (79%). Recrystallization from hexane yielded purified (38) m.p. 111°-112° C. Calc. % C 70.97, % H 3.25, % S 17.22: meas. % C 70.71, % H 3.26, % S 17.12.
Spiro-(8H-indeno[2,1-b]thiophen-8,4'-imidazolidine)-2',5'-dione (39) ##STR106## To a glass-lined, high-pressure steel reaction vessel was added ketone (38) (931.2 mg, 5 mol), potassium cyanide (1.01 g, 12.5 mmol), ammonium carbonate (1.45 g, 18 mmol) and 25 mL ethanol. The sealed vessel was heated at 115°-120° C. for 20 h. The work-up procedure was very similar to that for spiro-hydantoin (36) of Example XIII. The purified product (39), 200 mg, gave m/e 30 . 256. Calc. % C 60.92, % H 3.15, % N 10.96: meas. % C 60.88, % H 3.22, % H 10.79.
EXAMPLE XV
Spiro-(9H-pyrrolol[1,2-a]indol-9,4'-imidazolidine)-2',4'-dione (41) ##STR107##
9H-Pyrrolol[1,2-a]indole-9-one (40) was prepared exactly according to Josey and Jenner, J. Org. Chem., 27 (1962) 2466. The ketone (40) (2.5 g, 15 mmol), potassium cyanide (2.44 g, 37.5 mmol), ammonium carbonate (4.85 g, 45 mmol) and 50 mL 90% ethanol were added with mixing to a 125 cc stainless steel pressure reaction vessel. The sealed vessel was heated to 115°-118° C. for 48 h. The work-up was as in Example XIII in the work-up of (36). The collected and dried sample, 650 mg of (41), gave decomposition at >290 ° C. Calc. % C 65.26, % H 3.79, % N 17.56: meas. % C 65.16, % H 4.00, % N 17.59.
EXAMPLE XVI
Spiro-(9H-indeno[2,1-c]pyridin-9,4'-imidazolidine]-2',5'-dione (43 ) ##STR108##
2-Azafluoren-9-one (42) was prepared form 3-mesitoryl-4-phenyl-pyridine exactly according to Fuson and Miller, J. Am. Chem. Soc., 79 (1957) 3477. m.p. 152°-153° C. (reported 155.5°-156.5° C. by Fuson and Miller, ibid). The ketone (42) (0.5 g, 2.8 mmol), potassium cyanide (0.2 g, 3.1 % mmol), ammonium carbonate (1.0 g, 11 mmol) and 10 mL absolute ethanol were added with mixing to a 40 cc stainless steel pressure reactor. The sealed vessel was heated at 115°-120° C. for 30 h. The cooled reaction mixture was poured into 75 mL water, acidified with concentrated hydrochloric acid, filtered, the filtrate was made basic with 10% sodium hydroxide and filtered. The filtrate was neutralized with hydrochloric acid, the precipitate collected, washed with cold water and dried to yield 0.11 g of (43). m/e + . 251.
EXAMPLE XVII
Spiro-(2-chloro-7-fluoro-9H-fluoren-2,4'-imidazolidine)-2',5'-dione (45) ##STR109##
The spiro-hydantoin (44), spiro-(2-fluoro-9H-fluoren-9,4'-imidazolidine)-2', 5'-dione, was prepared exactly according to U.S. application Ser. Nos. 368,630 and 368,631. A mixture of (44) (5.36 g, 20 mmol), ferric chloride (0.25 g), glacial acetic acid solution of chlorine gas (5 g Cl 2 in 25 mL HOAc) and 200 mL glacial acetic acid were heated at 75° C. overnight. The cooled reaction mixture was poured into 200 mL water, stirred and the solid was collected by filtration. After water washes, the solid product was dried with 50° C. heat in vacuo to yield 2.3 g of (45). Calc. % C 59.52, % H 2.66, % N 9.25: meas. % C 59.35, % H 2.77, % N 9.26.
EXAMPLE XVIII
7-fluoro-5H-indeno[1,2-b]pyridine (50)
The procedure used for the preparation of 5-fluoro-1-indanone is that of Olivier and Marechal (E. Bull. Soc., Chim. Fr. (1973) 3092-3095) with modifications. The conversion of the ketone to 7-fluoro-5H-indeno[1,2-b]pyridine followed the general procedure described by Parcell and Hauck (J. Org. Chem. (1963) 28, 3468-3473) for the preparation of 5H-indeno[1,2b]pyridine from 1-indanone. ##STR110## Aluminum chloride (350 g, 2.62 mol) was covered with 650 mL methylene chloride and, while stirring under nitrogen, a solution of 3-chloropropionyl chloride (400 g, 3.15 mol, 300 mL) in 250 mL methylene chloride was added over 80 min. After 15 min., a solution of fluorobenzene (256 g, 2.66 mol, 250 mL) in 250 mL methylene chloride was added over 1 h 35 min. The reaction mixture was stirred, under nitrogen, at room temperature overnight (ca 18 h). The mixture was then poured onto 2.5 kg ice and transferred to a 4 L separatory funnel. After shaking well, the organic layer was removed and the aqueous portion was extracted with 2×50 mL methylene chloride. The combined organic extracts were washed with 3×200 mL saturated aqueous sodium bicarbonate and 1×200 mL brine, dried (MgSO 4 ), and evaporated to leave an oil which crystallized on cooling. Recrystallization from 2L hexane gave 325 g (67%). The filtrate was concentrated to 500 mL and cooled to provide another 42 g ((9%) of product (46). ##STR111## 3-Chloro-1-(4-fluorophenyl)propanone (46) (366 g, 1.97 mol) and 2.2L concentrated sulfuric acid were combined in a 5L flask equipped with a mechanical stirrer and heated over a period of 80 min. to 120° C. and then maintained at that temperature for 30 min. Hydrogen chloride evolution began at about 80° C. The reaction mixture was then cooled to 20° C., poured onto 5 kg of ice in a 22L flask equipped with a bottom drain and a mechanical stirrer, and extracted with 6×1L chloroform. The combined extracts were washed with 2×1L saturated aqueous sodium bicarbonate and 1×1L brine, dried (MgSO 4 ), and concentrated to leave a dark oil. Distillation gave the ketone, (47) 97.9 g (33%), bp (61°-66° C./0.15-0.2 mm, discolored by some dark material which was carried over during the process. ##STR112## A solution of 5-fluoro-1-indanone (47) (20.2 g, 0.135 mol), p-toluene-sulfonic acid monohydrate (0.015 eq, 390 mg), and piperidine (1.1 eq, 0.148 mol. 15 mL) in 300 mL toluene was refluxed under a Dean-Stark trap for 30 h. The reaction mixture was concentrated and distilled to provide the enamine, (48) 8.6 g (29%); bp 95°-100° C./1.5 mm. ##STR113## A solution of the enamine (8.6 g, 40 mmol) in 10 mL dry DMF was added all at once to a stirred solution of bromopropylamine hydrobromide (1.0 eq, 8.67 g) in 15 mL DMF. The stirred mixture was heated to 100° C. under nitrogen and then kept at that temperature for 4 h. The reaction mixture was poured into 60 mL cold 2N aqueous hydrochloric acid and extracted with 2×50 mL ethyl ether to remove any non-basic material. The aqueous solution was then covered with 50 mL ether, chilled, and basified using concentrated, sodium hydroxide. After separating the organic layer, the aqueous portion was extracted with 2×50 mL ether and the combined extracts were washed with 1×50 mL brine, dried (MgSO 4 ), and concentrated to leave 7.8 g of a dark oil. Distillation provided the tetrahydropyridine, 3.46 g (46%); bp 83°-86° C./0.15 mm. ##STR114## A mixture of the tetrahydropyridine (49) (3.19 g, 16.9 mmol), 10 mL xylene, 10 mL nitrobenzene, and 350 mg 10% palladium on carbon was refluxed for 4 h under a Dean-Stark trap under nitrogen. The reaction mixture was then cooled to room temperature and filtered through Celite, washing with ethyl acetate. The filtrate was extracted with 3×20 mL 2N aqueous hydrochloric acid and then the combined extracts were washed with 2×25 mL ethyl ether to remove non-basic material. Basification using solid potassium carbonate resulted in the precipitation of a dark green solid that was collected by filtration and washed well with water. This material 2.3 g (75%), was judged sufficiently pure by NMR to use in the next step. The material can further be purified by chromatography on silica gel using 30% ethyl acetate/hexane to give a yellow solid of (50) mp 80°-84° C.
The product (50) can be oxidized in accordance with Method VII and derivatized according to Method I into the corresponding spiro-hydantoin.
The product (50) can be derivatized in accordance with Methods II, III and IV into the corresponding spiro-thiazolidinedione, spiro-oxazolidinedione and spiro-succinimide.
EXAMPLE XIV
Following the foregoing text of preparations and examples, from readily available starting materials, the following spiro-derivatives of the present invention are prepared by analogy. All structional permutations occasioned by the substitution patterns and the values of U and Z on the following tricyclic structures are fully contemplated and intended as evidenced by the table entries.
______________________________________Unsubstituted Parent Structures for Compounds 1-328:A-D ##STR115## ##STR116## ##STR117## ##STR118## RingCompound No. Substitution U______________________________________1-4:A-D 7-F NH, NCH.sub.3, S, O5-8:A-D 6-F NH, NCH.sub.3, S, O9-12:A-D 5-F NH, NCH.sub.3, S, O13-16:A-D 4-F NH, NCH.sub.3, S, O17-20:A-D 7-F, 2-CH.sub.3 NH, NCH.sub.3 , S, O21-24:A-D 7-F, 3-CH.sub.3 NH, NCH.sub.3, S, O25-28:A-D 6-F, 2-CH.sub.3 NH, NCH.sub.3, S, O29-32:A-D 6-F, 3-CH.sub.3 NH, NCH.sub.3, S, O33-36:A-D 5-F, 2-CH.sub.3 NH, NCH.sub.3, S, O37-40:A-D 5-F, 3-CH.sub.3 NH, NCH.sub.3, S, O41-44:A-D 4-F, 2-CH.sub.3 NH, NCH.sub.3, S, O45-48:A-D 4-F, 3-CH.sub.3 NH, NCH.sub.3, S, O49-52:A-D 7-Cl NH, NCH.sub.3, S, O53-56:A-D 6-Cl NH, NCH.sub.3, S, O57-60:A-D 5-Cl NH, NCH.sub.3, S, O61-64:A-D 4-Cl NH, NCH.sub.3, S, O65-68:A-D 7-Cl, 2-CH.sub.3 NH, NCH.sub.3, S, O69-72:A-D 7-Cl, 3-CH.sub.3 NH, NCH.sub.3, S, O73-76:A-D 6-Cl, 2-CH.sub.3 NH, NCH.sub.3, S, O77-80:A-D 6-Cl, 3-CH.sub.3 NH, NCH.sub.3, S, O81-84:A-D 5-Cl, 2-CH.sub.3 NH, NCH.sub.3 , S, O85-88:A-D 5-Cl, 3-CH.sub.3 NH, NCH.sub.3, S, O89-92:A-D 4-Cl, 2-CH.sub.3 NH, NCH.sub.3, S, O93-96:A-D 4-Cl, 3-CH.sub.3 NH, NCH.sub.3, S, O97-100:A-D 7-F, 6-F NH, NCH.sub.3, S, O101-104:A-D 7-F, 5-F NH, NCH.sub.3, S, O105-108:A-D 7-F, 4-F NH, NCH.sub.3, S, O107-112:A-D 6-F, 5-F NH, NCH.sub.3, S, O113-116:A-D 6-F, 4-F NH, NCH.sub.3, S, O117-120:A-D 5-F, 4-F NH, NCH.sub.3, S, O121-124:A-D 7-Cl, 6-Cl NH, NCH.sub.3, S, O125-128:A-D 7-Cl, 5-Cl NH, NCH.sub.3, S, O129-132:A-D 7-Cl, 4-Cl NH, NCH.sub.3, S, O133-136:A-D 6-Cl, 5-Cl NH, NCH.sub.3, S, O137-140:A-D 6-Cl, 4-Cl NH, NCH.sub.3, S, O141-144:A-D 5-Cl, 4-Cl NH, NCH.sub.3, S, O145-148:A-D 7-F, 6-Cl NH, NCH.sub.3, S, O149-152:A- D 7-F, 5-Cl NH, NCH.sub.3, S, O153-156:A-D 7-F, 4-Cl NH, NCH.sub.3, S, O157-160:A-D 6-F, 7-Cl NH, NCH.sub.3, S, O161-164:A-D 6-F, 5-Cl NH, NCH.sub.3, S, O165-168:A-D 6-F, 4-Cl NH, NCH.sub.3, S, O169-172:A-D 5-F, 7-Cl NH, NCH.sub.3, S, O173-176:A-D 5-F, 6-Cl NH, NCH.sub.3, S, O177-180:A-D 5-F, 4-Cl NH, NCH.sub.3, S, O181-184:A-D 4-F, 7-Cl NH, NCH.sub.3, S, O185-188:A-D 4-F, 6-Cl NH, NCH.sub.3, S, O189-192:A-D 4-F, 5-Cl NH, NCH.sub.3, S, O193-196:A-D 7-F, 6-F, 2-CH.sub.3 NH, NCH.sub.3, S, O197-200:A-D 7-F, 5-F, 2-CH.sub.3 NH, NCH.sub.3, S, O201-204:A-D 7-F, 4-F, 2-CH.sub.3 NH, NCH.sub.3, S, O205-208:A-D 7-F, 6-F, 3-CH.sub.3 NH, NCH.sub.3, S, O209-212:A-D 7-F, 5-F, 3-CH.sub.3 NH, NCH.sub.3, S, O213-216:A-D 7-F, 4-F, 3-CH.sub.3 NH, NCH.sub.3, S, O217-220:A-D 6-F, 5-F, 2-CH.sub.3 NH, NCH.sub.3, S, O221-224:A-D 6-F, 4-F, 2-CH.sub.3 NH, NCH.sub.3, S, O225-228:A-D 6-F, 5-F, 3-CH.sub.3 NH, NCH.sub.3, S, O229-232:A-D 6-F, 4-F, 3-CH.sub.3 NH, NCH.sub.3, S, O233-236:A-D 5-F, 4-F, 2-CH.sub.3 NH, NCH.sub.3, S, O237-240:A-D 5-F, 4-F, 3-CH.sub.3 NH, NCH.sub.3, S, O241-244:A-D 6-Cl, 5-Cl, 2-CH.sub.3 NH, NCH.sub.3, S, O245-248:A-D 6-Cl, 5-Cl, 3-CH.sub.3 NH, NCH.sub.3, S, O249-252:A-D 6-Cl, 4-Cl, 2-CH.sub.3 NH, NCH.sub.3, S, O253-256:A-D 6-Cl, 4-Cl, 3-CH.sub.3 NH, NCH.sub.3, S, O257-260:A-D 6-(CH.sub.3S) NH, NCH.sub.3, S, O261-264:A-D 6-(CH.sub.3S), 2-CH.sub.3 NH, NCH.sub.3, S, O265-268:A-D 6-(CH.sub.3S), 3-CH.sub.3 NH, NCH.sub.3, S, O269-272:A-D 6-(CH.sub.3S(O)) NH, NCH.sub.3, S, O273-276:A-D 6-(CH.sub.3S(O)), 2-CH.sub.3 NH, NCH.sub.3, S, O277-280:A-D 6-(CH.sub.3S(O)), 3-CH.sub.3 NH, NCH.sub.3, S, O281-284:A-D 7-F, 6-(CH.sub.3S) NH, NCH.sub.3, S, O285-288:A-D 5-F, 6-(CH.sub.3S) NH, NCH.sub.3, S, O289-292:A-D 4-F, 6-(CH.sub.3S) NH, NCH.sub.3, S, O293-296:A-D 6-CF.sub.3 NH, NCH.sub.3, S, O297-300:A-D 6-CF.sub.3, 2-CH.sub.3 NH, NCH.sub.3, S, O301-304:A-D 6-CF.sub.3, 3-CH.sub.3 NH, NCH.sub.3, S, O305-308:A-D 6-[CH(CH.sub.3)COOH] NH, NCH.sub.3, S, O309-312:A-D 6-[CH(CH.sub.3)COOH], NH, NCH.sub.3, S, O 2-CH.sub.3313-316:A-D 6-[CH(CH.sub.3)COOH], NH, NCH.sub.3, S, O 3-CH.sub.3317-320:A-D 6-CH.sub.3 NH, NCH.sub.3, S, O321-324:A-D 6-CH.sub.3, 2-CH.sub.3 NH, NCH.sub.3, S, O325-328:A-D 6-CH.sub.3, 3-CH.sub.3 NH, NCH.sub.3, S, O______________________________________Unsubstituted Parent Structures for Compounds 329-656:A-D ##STR119## ##STR120## ##STR121## ##STR122## RingCompound No. Substitution U______________________________________329-332:A-D 7-F NH, NCH.sub.3, S, O333-336:A-D 6-F NH, NCH.sub.3, S, O337-340:A-D 5-F NH, NCH.sub.3, S, O341-344:A-D 8-F NH, NCH.sub.3, S, O345-348:A-D 7-F, 2-CH.sub.3 NH, NCH.sub.3, S, O349-352:A-D 7-F, 3-CH.sub.3 NH, NCH.sub.3, S, O353-356:A-D 6-F, 2-CH.sub.3 NH, NCH.sub.3, S, O357-360:A-D 6-F, 3-CH.sub.3 NH, NCH.sub.3, S, O361-364:A-D 5-F, 2-CH.sub.3 NH, NCH.sub.3, S, O365-368:A-D 5-F, 3-CH.sub.3 NH, N CH.sub.3, S, O369-372:A-D 8-F, 2-CH.sub.3 NH, NCH.sub.3, S, O373-376:A-D 8-F, 3-CH.sub.3 NH, NCH.sub.3, S, O377-380:A-D 7-Cl NH, NCH.sub.3, S, O381-384:A-D 6-Cl NH, NCH.sub.3, S, O385-388:A-D 5-Cl NH, NCH.sub.3, S, O389-392:A-D 8-Cl NH, NCH.sub.3, S, O393-396:A-D 7-Cl, 2-CH.sub.3 NH, NCH.sub.3, S, O397-400:A-D 7-Cl, 3-CH.sub.3 NH, NCH.sub.3, S, O401-404:A-D 6-Cl, 2-CH.sub.3 NH, NCH.sub.3, S, O405-408:A-D 6-Cl, 3-CH.sub.3 NH, NCH.sub.3, S, O409-412:A-D 5-Cl, 2-CH.sub.3 NH, NCH.sub.3, S, O413-416:A-D 5-Cl, 3-CH.sub.3 NH, NCH.sub.3, S, O417-420:A-D 8-Cl, 2-CH.sub.3 NH, NCH.sub.3, S, O421-424:A-D 8-Cl, 3-CH.sub.3 NH, NCH.sub.3, S, O425-428:A-D 7-F, 6-F NH, NCH.sub.3, S, O429-432:A-D 7-F, 5-F NH, NCH.sub.3 , S, O433-436:A-D 7-F, 8-F NH, NCH.sub.3, S, O437-440:A-D 6-F, 5-F NH, NCH.sub.3, S, O441-444:A-D 6-F, 8-F NH, NCH.sub.3, S, O445-448:A-D 5-F, 8-F NH, NCH.sub.3, S, O449-452:A-D 7-Cl, 6-Cl NH, NCH.sub.3, S, O453-456:A-D 7-Cl, 5-Cl NH, NCH.sub.3, S, O457-460:A-D 7-Cl, 8-Cl NH, NCH.sub.3, S, O461-464:A-D 6-Cl, 5-Cl NH, NCH.sub.3, S, O465-468:A-D 6-Cl, 8-Cl NH, NCH.sub.3, S, O469-472:A-D 5-Cl, 8-Cl NH, NCH.sub.3, S, O473-476:A-D 7-F, 6-Cl NH, NCH.sub.3, S, O477-480:A-D 7-F, 5-Cl NH, NCH.sub.3, S, O481-484:A-D 7-F, 8-Cl NH, NCH.sub.3, S, O485-488:A-D 6-F, 7-Cl NH, NCH.sub.3, S, O489-492:A-D 6-F, 5-Cl NH, NCH.sub.3, S, O493-496:A-D 6-F, 8-Cl NH, NCH.sub.3, S, O497-500:A-D 5-F, 7-Cl NH, NCH.sub.3, S, O501-504:A-D 5-F, 6-Cl NH, NCH.sub.3, S, O505-508:A-D 5-F, 8-Cl NH, NCH.sub.3, S, O509-512:A-D 8-F, 7-Cl NH, NCH.sub.3, S, O513-516:A-D 8-F, 6-Cl NH, NCH.sub.3, S, O517-520:A-D 8-F, 5-Cl NH, NCH.sub.3, S, O521-524:A-D 7-F, 6-F, 2-CH.sub.3 NH, NCH.sub.3, S, O525-528:A-D 7-F, 5-F, 2-CH.sub.3 NH, NCH.sub.3, S, O529-532:A-D 7-F, 8-F, 2-CH.sub.3 NH, NCH.sub.3, S, O533-536:A-D 7-F, 6-F, 3-CH.sub.3 NH, NCH.sub.3, S, O537-540:A-D 7-F, 5-F, 3-CH.sub.3 NH, NCH.sub.3, S, O541-544:A-D 7-F, 8-F, 3-CH.sub.3 NH, NCH.sub.3, S, O545-548:A-D 6-F, 5-F, 2-CH.sub.3 NH, NCH.sub.3, S, O549-552:A-D 6-F, 8-F, 2-CH.sub.3 NH, NCH.sub.3, S, O553-556:A-D 6-F, 5-F, 3-CH.sub.3 NH, NCH.sub.3, S, O557-560:A-D 6-F, 8-F, 3-CH.sub.3 NH, NCH.sub.3, S, O561-564:A-D 5-F, 8-F, 2-CH.sub.3 NH, NCH.sub.3, S, O565-568:A-D 5-F, 8-F, 3-CH.sub.3 NH, NCH.sub.3, S, O569-572:A-D 6-Cl, 5-Cl, 2-CH.sub.3 NH, NCH.sub.3, S, O573-576:A-D 6-Cl, 5-Cl, 3-CH.sub.3 NH, NCH.sub.3, S, O577-580:A-D 6-Cl, 8-Cl, 2-CH.sub.3 NH, NCH.sub.3, S, O581-584:A-D 6-Cl, 8-Cl, 3-CH.sub.3 NH, NCH.sub.3, S, O585-588:A-D 6-(CH.sub.3S) NH, NCH.sub.3, S, O589-592:A-D 6-(CH.sub.3S), 2-CH.sub.3 NH, NCH.sub.3, S, O593-596:A-D 6-(CH.sub.3S), 3-CH.sub.3 NH, NCH.sub.3, S, O597-600:A-D 6-(CH.sub.3S(O)) NH, NCH.sub.3, S, O601-604:A-D 6-(CH.sub.3S(O)), 2-CH.sub.3 NH, NCH.sub.3, S, O605-608:A-D 6-(CH.sub.3S(O)), 3-CH.sub.3 NH, NCH.sub.3, S, O609-612:A-D 7-F, 6-(CH.sub.3S) NH, NCH.sub.3, S, O613-616:A-D 5-F, 6-(CH.sub.3S) NH, NCH.sub.3, S, O617-620:A-D 8-F, 6-(CH.sub.3S) NH, NCH.sub.3, S, O621-624:A-D 6-CF.sub.3 NH, NCH.sub.3, S, O625-628:A-D 6-CF.sub.3, 2-CH.sub.3 NH, NCH.sub.3, S, O629-632:A-D 6-CF.sub.3, 3-CH.sub.3 NH, NCH.sub.3, S, O633-636:A-D 6-[CH(CH.sub.3)COOH] NH, NCH.sub.3, S, O637-640:A-D 6-[CH(CH.sub.3)COOH], NH, NCH.sub.3, S, O 2-CH.sub.3641-644:A-D 6-[CH(CH.sub.3)COOH], NH, NCH.sub.3, S, O 3-CH.sub.3645-648:A-D 6-CH.sub.3 NH, NCH.sub.3, S, O649-652:A-D 6-CH.sub.3, 2-CH.sub.3 NH, NCH.sub.3, S, O653-656:A-D 6-CH.sub.3, 3-CH.sub.3 NH, NCH.sub.3, S, O______________________________________Unsubstituted Parent Structures for Compounds 657-706:A-D ##STR123## ##STR124## ##STR125## ##STR126## RingCompound No. Substitution______________________________________657:A-D 6-F658:A-D 7-F659:A-D 8-F660:A-D 9-F661:A-D 3-F662:A-D 6-F, 3-F663:A-D 7-F, 3-F664:A-D 8-F, 3-F665:A-D 9-F, 3-F666:A-D 6-Cl667:A-D 7-Cl668:A-D 8-Cl669:A-D 9-Cl670:A-D 6-Cl, 3-F671:A-D 7-Cl, 3-F672:A-D 8-Cl, 3-F673:A-D 9-Cl, 3-F674:A-D 6-F, 7-F675:A-D 6-F, 8-F676:A-D 6-F, 9-F677:A-D 7-F, 8-F678:A-D 7-F, 9-F679:A-D 8-F, 9-F680:A-D 3-F, ,7-F, 8-F681:A-D 7-(CH.sub.3S)682:A-D 7-(CH.sub.3S(O))683:A-D 7-[CH(CH.sub.3)COOH]684:A-D 7-[CH(CH.sub.3)COOH], 3-CH.sub.3685:A-D 7-[CH(CH.sub.3)COOH], 2-CH.sub.3686:A-D 7-[CH(CH.sub.3)COOH], 4-CH.sub.3687:A-D 6-[CH(CH.sub.3)COOH]687:A-D 6-[CH(CH.sub.3)COOH], 3-CH.sub.3688:A-D 6-[CH(CH.sub.3)COOH], 2-CH.sub. 3689:A-D 6-[CH(CH.sub.3)COOH], 4-CH.sub.3690:A-D 7-CH.sub.3691:A-D 7-(CH.sub.3O)692:A-D 7-CF.sub.3693:A-D 7-COOH694:A-D 7-CONH.sub.2695:A-D 6-CH.sub.2 COOH696:A-D 6-CH.sub.2 COOH, 3-CH.sub.3697:A-D 6-CH.sub.2 COOH, 2-CH.sub.3698:A-D 6-CH.sub.2 COOH, 4-CH.sub.3699:A-D 6-COOH700:A-D 6-CH.sub.2NH.sub.2701:A-D 7-CH.sub.2 COOH702:A-D 7-CH.sub.2 COOH, 3-CH.sub.3703:A-D 7-CH.sub.2 COOH, 2-CH.sub.3704:A-D 7-CH.sub.3 COOH, 4-CH.sub.3705:A-D 7-COOH, 3-CH.sub.3706:A-D 7-CH.sub.2NH.sub.2______________________________________Unsubstituted Parent Structures for Compounds 707-744:A-D ##STR127## ##STR128## ##STR129## ##STR130## RingCompound No. Substitution______________________________________707:A-D 8-F708:A-D 7-F709:A-D 6-F710:A-D 5-F711:A-D 7-Cl712:A-D 5-F, 6-F713:A-D 5-F, 7-F714:A-D 5-F, 8-F715:A-D 6-F, 7-F716:A-D 6-F, 8-F717:A-D 7-F, 8-F718:A-D 7-(CH.sub.3S)719:A-D 7-(CH.sub.3S(O))720:A-D 7-COOH721:A-D 7-CH.sub.3722:A-D 7-CF.sub.3723:A-D 7-[CH(CH.sub.3)COOH]724:A-D 7-[CH(CH.sub.3)COOH], 2-CH.sub.3725:A-D 7-[CH(CH.sub.3)COOH], 3-CH.sub.3726:A-D 7-[CH(CH.sub.3)COOH], 4-CH.sub.3727:A-D 6-[CH(CH.sub.3)COOH], 2-CH.sub.3728:A-D 6-[CH(CH.sub.3)COOH], 3-CH.sub.3729:A-D 6-[CH(CH.sub.3)COOH], 4-CH.sub.3730:A-D 6-[CH(CH.sub.3)COOH], 5-CH.sub.3______________________________________Unsubstituted Parent Structures for Parent Compounds 731-766:A-D ##STR131## ##STR132## ##STR133## ##STR134## RingCompound No. Substitution______________________________________731:A-D 8-F732:A-D 7-F733:A-D 6-F734:A-D 5-F735:A-D 7-Cl736:A-D 5-F, 6-F737:A-D 5-F, 7-F738:A-D 5-F, 8-F739:A-D 6-F, 7-F740:A- D 6-F, 8-F741:A-D 7-F, 8-F742:A-D 7-(CH.sub.3S)743:A-D 7-(CH.sub.3 S(O))744:A-D 7-COOH745:A-D 7-CH.sub.3746:A-D 7-CF.sub.3747:A-D 7-[CH(CH.sub.3)COOH]748:A-D 7-[CH(CH.sub.3)COOH], 1-CH.sub.3749:A-D 7-[CH(CH.sub.3)COOH], 3-CH.sub.3750:A-D 7-[CH(CH.sub.3)COOH], 4-CH.sub.3751:A-D 6-[CH(CH.sub.3)COOH]752:A-D 6-[CH(CH.sub.3)COOH], 1-CH.sub.3753:A-D 6-[CH(CH.sub.3)COOH], 3-CH.sub.3754:A-D 6-[CH(CH.sub.3)COOH], 4-CH.sub.3755:A-D 7-CONH.sub.2756:A-D 6-CONH.sub.2757:A-D 7-CH.sub.2 COOH758:A-D 7-CH.sub.2 COOH, 1-CH.sub.3759:A-D 7-CH.sub.2 COOH, 3-CH.sub.3760:A-D 7-CH.sub.2 COOH, 4-CH.sub.3761:A-D 6-CH.sub.2 COOH762:A-D 6-CH.sub.2 COOH, 1-CH.sub.3763:A-D 6-CH.sub.2 COOH, 3-CH.sub.3764:A-D 6-CH.sub.2 COOH, 4-CH.sub.3765:A-D 6-COOH766:A-D 6-Cl______________________________________Unsubstituted Parent Structures for Compounds 767-792:A-D ##STR135## ##STR136## ##STR137## ##STR138## RingCompound No. Substitution______________________________________767:A-D 9-F768:A-D 8-F769:A-D 7-F770:A-D 6-F771:A-D 7-Cl772:A-D 8-Cl773:A-D 7-(CH.sub.3S)774:A-D 7-(CH.sub.3S(O))775:A-D 7-[CH(CH.sub.3)COOH]776:A-D 6-[CH(CH.sub.3)COOH]777:A-D 7-COOH778:A-D 7-CONH.sub.2779:A-D 7-CF.sub.3780:A-D 7-CH.sub.2 COOH781:A-D 8-CH.sub.3 COOH782:A-D 7-CH.sub.2 COOC.sub.2 H.sub.5783:A-D 8-CH.sub.2 COOC.sub.2 H.sub.5784:A-D 7-F, 8-F785:A-D 7-Cl, 8-Cl786:A-D 7-CH.sub.3787:A-D 7-CH.sub.2NH.sub.2788:A-D 7-NO.sub.2789:A-D 8-NO.sub.2790:A-D 7-CH.sub.2OH791:A-D 8-COOH792:A-D 8-CONH.sub.2______________________________________Unsubstituted Parent Structures for Compounds 793-847:A-D ##STR139## ##STR140## ##STR141## ##STR142## RingCompound No. Substitution______________________________________793:A-D 8-F794:A-D 7-F795:A-D 6-F796:A-D 5-F797:A-D 8-F, 1-CH.sub.3798:A-D 8-F, 2-CH.sub.3799:A-D 8-F, 3-CH.sub.3800:A-D 7-F, 1-CH.sub.3801:A-D 7-F, 2-CH.sub.3802:A-D 7-F, 3-CH.sub.3803:A-D 6-F, 1-CH.sub.3804:A-D 6-F, 2-CH.sub.3805:A-D 6-F, 3-CH.sub.3806:A-D 5-F, 1-CH.sub.3807:A-D 5-F, 2-CH.sub.3808:A-D 5-F, 3-CH.sub.3809:A-D 7-Cl810:A-D 7-Cl, 1-CH.sub.3811:A-D 7-Cl, 2-CH.sub.3812:A-D 7-Cl, 3-CH.sub.3813:A-D 7-(CH.sub.3S)814:A-D 7-(CH.sub.3S), 1-CH.sub.3815:A-D 7-(CH.sub.3S), 2-CH.sub.3816:A-D 7-(CH.sub.3S), 3-CH.sub.3817:A-D 7-[CH.sub.3S(O)]818:A-D 7-[CH.sub.3S(O)], 1-CH.sub.3819:A-D 7-[CH.sub.3S(O)], 2-CH.sub.3820:A-D 7-[CH.sub.3S(O)], 3-CH.sub.3821:A-D 6-F, 7-F822:A-D 7-Cl, 6-F823:A-D 7-[CH(CH.sub.3)COOH]824:A-D 7-[CH(CH.sub.3)COOH] , 1-CH.sub.3825:A-D 7-[CH(CH.sub.3)COOH], 2-CH.sub.3826:A-D 7-[CH(CH.sub.3)COOH], 3-CH.sub.3827:A-D 6-[CH(CH.sub.3)COOH]828:A-D 6-[CH(CH.sub.3)COOH], 1-CH.sub.3829:A-D 6-[CH(CH.sub.3)COOH], 2-CH.sub.3830:A-D 6-[CH(CH.sub.3)COOH], 3-CH.sub.3831:A-D 6-CH.sub.2 COOH832:A-D 6-CH.sub.2 COOH, 1-CH.sub.3833:A-D 6-CH.sub.2 COOH, 2-CH.sub.3834:A-D 6-CH.sub.2 COOH, 3-CH.sub.3835:A-D 7-CH.sub.2 COOH836:A-D 7-CH.sub.2 COOH, 1-CH.sub.3837:A-D 7-CH.sub.2 COOH, 2-CH.sub.3838:A-D 7-CH.sub.3 COOH, 3-CH.sub.3839:A-D 6-Cl840:A-D 6-COOH841:A-D 6-CONH.sub.2842:A-D 7-COOH843:A-D 7-CONH.sub.2844:A-D 6-OCH.sub.3845:A-D 3-Cl846:A-D 6-CH.sub.2 NH.sub.2847:A-D 7-CH.sub.2 NH.sub.2______________________________________Unsubstituted Parent Structure for Compounds 848-876:A-D ##STR143## ##STR144## ##STR145## ##STR146## RingCompound No. Substitution Z______________________________________848-849:A-D 6-F O, S850-851:A-D 7-F O, S852-853:A-D 6-Cl O, S854-855:A-D 7-Cl O, S856-857:A-D 6-COOH O, S858-859:A-D 6-(CH.sub.3S) O, S860-861:A-D 6-[CH(CH.sub.3)COOH] O, S862-863:A-D 7-[CH(CH.sub.3)COOH] O, S864-865:A-D 6-CH.sub.2 COOH O, S866-867:A-D 7-CH.sub.2 COOH O, S868-869:A-D 7-COOH O, S870-871:A-D 6-CONH.sub.2 O, S872-873:A-D 7-CONH.sub.2 O, S874-875:A-D 6-F, 7-F O, S874-875:A-D 6-F, 7-F O, S______________________________________Unsubstituted Parent Structure for Compounds 877-940:A-D ##STR147## ##STR148## ##STR149## ##STR150## RingCompound No. Substitution______________________________________877:A-D 1-F878:A-D 2-F879:A-D 3-F880:A-D 4-F881:A-D 1-F, 5-F882:A-D 1-F, 6-F883:A-D 1-F, 7-F884:A-D 1-F, 8-F885:A-D 2-F, 5-F886:A-D 2-F, 6-F887:A-D 2-F, 7-F888:A-D 3-F, 5-F889:A-D 3-F, 6-F890:A-D 4-F, 5-F891:A-D 2-Cl892:A-D 2-Cl, 5-F893:A-D 2-Cl, 6-F894:A-D 2-Cl, 7-F895:A-D 2-Cl, 8-F896:A-D 2-F, 3-F, 7-F897:A-D 2-F, 7-CH.sub.3898:A-D 2-F, 7-(CH.sub.3S)899:A-D 2-F, 7-(CH.sub.3S(O))900:A-D 2-F, 7-(CH.sub.3SO.sub.2)901:A-D 2-Cl, 7-(CH.sub.3S)902:A-D 2-Cl, 7-(CH.sub.3S(O))903:A-D 2-Cl, 7-(CH.sub.3SO.sub.2)904:A-D 20F, 7-(CH.sub.3 O)905:A-D 7-F, 2-COOH906:A-D 6-F, 2-COOH907:A-D 7-F, 3-COOH908:A-D 6-F, 3-COOH909:A-D 2-F, 2-[CH(CH.sub.3)COOH]910:A-D 2-Cl, 2-[CH(CH.sub.3)COOH]911:A-D 2-F, 2-[CH(CH.sub.3)COOH]912:A-D 2-Cl, 2-[CH(CH.sub.3)COOH]913:A-D 2-(CH.sub.3S), 7-[CH(CH.sub.3)COOH]914:A-D 2-[CH.sub.3S(O)], 7-[CH(CH.sub.3)COOH]915:A-D 2-(CH.sub.3S), 6-[CH(CH.sub.3)COOH]916:A-D 2-[CH.sub.3S(O)], 6-[ CH(CH.sub.3)COOH]917:A-D 7-F, 2-CONH.sub.2918:A-D 7-Cl, 2-CONH.sub.2919:A-D 2-F, 3-F, 7-(CH.sub.3S)920:A-D 2-F, 3-F, 7-[CH.sub.3 S(O)]921:A-D 2-F, 7-CF.sub.3922:A-D 2-F, 7-OH923:A-D 2-F, 6-OH924:A-D 2-F, 5-OH925:A-D 2-F, 7-(CH.sub.3O)926:A-D 2-COOH, 6-F, 7-F927:A-D 3-COOH, 6-F, 7-F928:A-D 2-(CH.sub.2S), 3-F929:A-D 2-(CH.sub.3S), 4-F930:A-D 2-F, 3-F, 7-(CH.sub.3S)931:A-D 2-F, 3-F, 7-[CH.sub.3S(O)-]932:A-D 2-F, 3-(CH.sub.3S), 7-F933:A-D 2-F, 3-[CH.sub.3 S(O)-], 7-F934:A-D 1-F, 7-NO.sub.2935:A-D 2-F, 7-NO.sub.2936:A-D 3-F, 7-NO.sub.2937:A-D 4-F, 7-NO.sub.2938:A-D 2-[CH.sub.2 (CH.sub.3)COOH]939:A-D 2-CH.sub.2 COOH940:A-D 2-CH.sub.2 COOH, 7-F______________________________________
EXAMPLE XX ##STR151##
Preferred derivatives from Example XIX may be oxidized in accordance with Method VI to yield the corresponding N-oxides. Similarly, other N-oxides are prepared form other spiro-tricyclic aromatic azine derivatives of the present invention.
Alternatively, an indenopyridine or indenopyridine ketone may be oxidized in accordance with Method V to the corresponding N-oxide prior to spiro derivatization according to Methods I, III or IV. ##STR152##
EXAMPLE XXI
The sodium salt of spiro-(2-fluoro-9H-fluoren-2,5'-thiazolidine)-2', 4'-dione, spiro-(6-fluoro-9H-pyrrolol[1,2-a]indol-9,4'-imidazolidine)-2,4'-dione, spiro-(7-fluoro-5H-indeno[1,2-b]pyridin-5,4'-imidazolidine)-2',5'-dione or any of their related spiro tricyclic congeners which are the subject of the present invention are prepared by dissolving any of said compounds in water containing an equivalent amount in moles of sodium hydroxide and then freeze-drying the mixture. In this way, the desired alkali metal salt of the spiro-hydantoin, spiro-thiazolidinedione, spiro-oxazolidinedione or spiro-succinimide can be prepared. In those cases where the aromatic substituents contain carboxylic acid moieties (e.g., isopropanoic acid substituent), one equivalent of base will yield the corresponding sodium carboxylate salt. In such cases as the aforementioned, two mole equivalents will yield the disodium salt. By this method, the desired alkali metal salt is obtained as an amorphous powder which is soluble in water.
In like manner, the potassium and lithium slats are analogously prepared, as are the alkali metal salts of all other spiro-tricycle compounds of this invention which are reported in Examples I-XVII and XIX, respectively.
EXAMPLE XVIII
The calcium salt of spiro-(2fluoro-9H-fuoren-9,5'-thiazolidine)-2',4'-dione is prepared by dissolving said compound in water containing an equivalent amount in moles of calcium hydroxide and then freeze-drying the mixture. The corresponding magnesium salt is also prepared in this manner, as are all other alkaline-earth metal salts not only of this particular compound, but also those spiro-tricyclic analogs previously described in Examples I-XVII and XIX, respectively.
EXAMPLE XXIII
The hydrogen chloride salt of spiro-(7-fluoro-9H-indeno[2,1-c]pyridin-9,4'-imidazolidine)-2',5'-dione, spiro-(7-fluoro-5H-indeno[1,2-b]pyridine-5,4'-imidazolidine)- 2',5'-dione or spiro-(7-fluoro-5H-indeno[1,2,-b]5,5'-thiazolidine)-2',4'-dione in 1.0 to 1.5 equivalent amount of 1N to 10N hydrochloric acid and then freeze-drying the mixture in a manner to remove excess hydrochloric acid. By this method the aforementioned and related spiro-tricyclic azine analogs, previously described in Example XIX, and prepared as hydrogen chloride salt powders which are soluble in water.
EXAMPLE XXIV
A dry solid pharmaceutical composition is prepared by mixing the following materials together in the proportions by weight specified:
______________________________________Spiro-(2-fluoro-9,5'-thiazolidine)-2',4'-dione 50Sodium Citrate 20Alginic Acid 5Polyvinylpyrrolidone 15Magnesium Stearate 5______________________________________
The dry composition is thoroughly blended, tablets are punched from the resulting mixture, each tablet being of such size that it contains 100 mg of the active ingredient. Other tablets are also prepared in a likewise manner containing 10, 25 and 200 mg of active ingredient, respectively, by merely using an appropriate quantity by weight of the spiro-thiazolidinedione in each case. Likewise other related examples of spiro-thiazoidinediones, spiro-imidazolidinediones, spiro-oxazolidinediones, spiro-succinimides and be formulated as tablets on a respective weight proportion.
EXAMPLE XXV
A dry solid pharmaceutical composition is prepared by combining the following materials together in the weight proportions indicated below:
______________________________________Spiro-(7-fluoro-5 .sub.-- H-indeno[1,2-b]pyridin- 505,4'-imidazolidine)-2',5'-dioneCalcium Carbonate 20Polyethylene glycol, Average Molecular Weight 25,000 30______________________________________
The dry solid mixture is thoroughly mixed until uniform in composition. The powdered product is then used to fill soft elastic and hard-gelatin capsules so as to provide capsules containing 200 mg of the active ingredient.
EXAMPLE XXVI
The following spiro-tricyclic compounds of the Examples and Preparations previously described were tested for their ability to inhibit or reduce aldose reductase enzyme activity. The procedure for the aldose reductase enzyme activity inhibition test is described in the following publications:
a) P. F. Kador, L. O. Merola and J. H. Kinoshita, Docum. Ophthal. Proc. Series, 18, 117-124 (1979);
b) P. F. Kador, J. H. Kinoshita, W. H. Tung and L. T. Chylack, Jr., Invest. Opthalmol. Vis. Sci., 19, 980-982 (1980);
c) P. F. Kador, D. Carper and J. H. Kinoshita, Analytical Biochemistry, 114, 53-58 (1981).
Wherein the assay mixture used in the tests containing 0.1M potassium phosphate buffer, pH 6.2, 0.2 mM nicotoinamide ademine dinucleotide phosphate (NADPH), 10 mM D,L-glyceraldehyde, and an appropriate volume of the enzyme preparation, thermostated at 25° C. in the cell compartment of a spectrophotometer. These conditions are identical to those published in references (a), (b) and (c), except that a larger NADPH concentration was employed. This insured a linear reaction rate for longer time periods since one product of the reaction, NADP + , markedly inhibits the enzyme. The control sample contained no added inhibitor. In order to measure aldose reductase inhibition activity, varying concentrations of the inhibitor examples set forth below were added to the standard incubation mixture. The control, containing the enzyme and NADPH, gave a very small, but measurable rate; thus, it served as the blank against which to measure the glyceraldehyde-dependent rate of NADPH oxidation. The tests were conducted with human placental aldose reductase enzyme. The results of the tests are the product of multiple assays. The IC50 data for each compound is expressed below in terms of concentration of compound required to inhibit 50% human placental aldose reductase enzyme activity. A test compound is considered active if it inhibits or reduces human aldose reductase activity at 1×10 -4 M concentration or less. The following list is provided as a representative sample of the biological activity of the spiro-tricyclic derivatives of the present invention. ##STR153##
Research (Kador, Merola and Kinoshite, Docum. Ophthal. Proc. Series 18 (1979) 117) has indicated that the evaluation of aldose reductase inhibitors for potential human chemotheraphy may require testing with human aldose reductase. There are species-linked differences in the susceptibility for inhibition of aldose reductase. For example, rat lens aldose reductase behaves differently from human placental aldose reductase with respect to inhibition by synthetic chemical inhibitors.
EXAMPLE XXVII
According to the procedures of Kador, Merola and Kinoshite, Docum. Ohthal. Proc. Series, 18 (1979) 117 and Kador Sharpless,, Biophysical Chemistry, 8 (1978) 81 the inhibition exerted by examples of the present invention where evaluated against rate lens aldose reductase. Otherwise, the inhibitor assay is identical to that employed against human aldose reductase in Example XXVI. Representative rat lens aldose reductase inhibition is presented in terms of the concentration of test compound required to reduce rate lens aldose reductase enzyme activity by 50%. A test compound is considered active if it inhibits or reduces rate lens aldose reductase activity at 1×10 -4 M concentration or less. ##STR154##
EXAMPLE XXVIII
Aldose reductase inhibitor potency may be evaluated in rate lens culture assays where 30 mM of glucose, galactose or xylose can be used in culture to induce a `sugar` cataract. In addition to monitoring lens clarity, certain biochemical radiolabeled markers (e.g., choline -3 H and 86 Rb) are employed to measure lens function. See Obazawa, Merola and Kinoshita, Invest. Ophthalmol., 13 (1974) 204 and Jernigan, Kador and Kinoshita, Exp. Eye Res., 32 (1981) 709.
In the present case, the 30 mM xylose cataract model was selected because 30 mM xylose is more effective in product `sugar` catarcats than either 30 mM glucose pr 30 mM galactose. The general procedure is as follows: a) Sprague-Dawley rats of 75-100 g body weight are sacrificed and the lenses removed immediately; b) the contralateral lens of the pair of lenses is employed as untreated control lens; c) the test lens is cultured in TC-199 culture media in the presence of 30 mM xylose, 30 mM xylose plus a selected concentration of test compound or a selected concentration of test compound; d) the contralateral control lens is treated identical to the test lens except no test compound or xylose is included; a) the matched lens pairs are cultured for 18 h in a CO 2 incubator; f) the lenses are composed morpohologically and weighed. All lenses, control and test groups, are allowed to preincubate for 1 hr in respective control media or drug control media prior to transfer to xylose media or xylose-drug media. In those cases where radiolabelled markers are to be measured, the lenses are treated as aforementioned except the radiolabelled marker(s) are added to the culture at four hours before harvesting. Radiolabelled markers include choline -3 H [methyl -14 C]-choline chloride available from New England Nuclear), AIBA -14 C (α-[1 -14 C]-(CH 2 ) 2 C(NH 2 )COOH available from New England Nuclear) and 86 Rb. The effect of xylose on lens uptake of 86 Rb, lens uptake of amino acid (AIBA - 14 C) and lens uptake of choline -3 H and the effectivness of representative compounds of the present invention to preserve normal lens morphology is reported here.
The effect of 30 mM xylose and 30 mM xylose plus selected concentrations of test compound on radioactivity ratio is expressed as L/M % of control. L/M % of control is defined as the test lens radioactivity divided by culture media radioactivity as a percentage of the control contralateral lens radioactivity to media radioactivity ratio under identical test conditions but always without xylose or test compound in the control. The effect of 30 mM xylose in the culture media gives a reproducible deleterious effect on the lens as measured by the various L/M %. Furthermore, after incubation of the lens in 30 mM xylose in the TC-199 culture media, the lens gains 20% weight (mostly water weight increase based on dry lens weight measurements) and becomes opaque in the cortex of the lens. Each experiment requires 20-40 pairs of lenses to determine the potency of a selected aldose reductase inhibitor. For comparison purposes, representative examples of the present invention will be profiled in the following table against examples from U.S. Pat. application Ser. Nos. 368,630 and 368,631.
REPRESENTATIVE COMPOUNDS EVALUATED
A. Spiro(-2-fluoro-9H-fluoren-9,4'- imidazolidine)-2',5'-dione;
B. Spiro-(2,7-difluoro-9H-fluoren-9,4'-imidazolidine)-2',5'-dione;
C. Spiro-(2-fluoro-9H-fluoren-9,5'-thiazolidine)-2', 4'-dione;
D. Spiro-(2,7-difluoro-9H-fluoren-9,5'- thiazolidine)-2',4'-dione.
______________________________________Radiolabel Uptake-L/M % Table (1) (2) (3)Compound* L/M % L/M % L/M %______________________________________None 47 33 45A 73 50 55B 105 87 82C 77 58 70D 109 85 83______________________________________ *Compound concentration 7.5 × 10.sup.-7 M in culture media. (1) L/M % = Lens uptake of choline .sup.-3 H after 18 h 30 mM xylose culture. (2) L/M % = Lens uptake of AIBA .sup.-14 C (amino acid) after 18 h 30 mM xylose culture. (3) L/M % = Lens uptake of .sup.86 Rb after 18 h 30 mM xylose culture.
In all cases Compounds A, B C and D prevented lens opacification and lens wet weight increase at compound concentration of 7.5×10 -7 M in the culture media.
Compound A and B according to U.S. application Ser. Nos. 368,360 and 368,631 are wholly effective in preventing cataract in galactosemic rats when administered per oral by gauge once a daily at 1.26 and 0.4 mg/kg respectively. In another efficacy study reported in the same applications, Compound A was found to prevent cataract and significantly preserve motor nerve conduction velocity in chronic streptozotocin-induced rats at 8 mg/kg per oral per day.
The following Examples XXIX-XXXVIII are presented to further illustrate methods for synthesizing certain preferred species of the present invention.
EXAMPLE XXIX
General Procedure for the Synthesis of 2,4,7-trifluoro-5-methylthiospiro[9H-fluorene-9,4'-imidazoldine[-2',5'-dione ##STR155##
2,4,7-Trifluoro-5-nitrofluorene was oxidized to the fluorenone using sodium dichromate in acetic acid and then reduced to 5-amino-2,4,7-trifluorofluorenone using tin(II)chloride in a mixture of ethanol and concentrated hydrochloric acid. The amine was converted to the 5-diazonium tetrafluoroborate salt by treatment with sodium nitrite in a mixture of tetrahydrofuran and aqueous fluoroboric acid. The material was allowed to react with potassium ethyl xanthate in a hot mixture of water and toluene to provide ethyl 2,4,7-trifluoro-9oxofluoren-5-yl xanthate which was then hydrolyzed using ethanolic sodium hydroxide and S-methylated with methyl iodide to give 2,4,7-tri-fluoro-5-methylthiofluorenone. Hydantoin formation was accomplished by heating an ethanol solution of the ketone, potassium cyanide, ammonium carbonate at 115° C. for 15 hours.
EXAMPLE XXX
General Procedure for the Synthesis of 2,4,7-trifluoro-5-methylspiro[9H-fluorene-9,4'-imidazolidine]-2',5'-dione ##STR156##
Treatment of 2,7-difluor-4-methyl-9H-fluorenone in acetic acid with a mixture of nitric acid and sulfuric acid gave 2,7-difluoro-4-methyl-5-nitro-9H-fluorenone as the major product. 5-Amino-2,7-difluoro-4-methyl-9H-fluorenone was obtained by reduction using tin(II)chloride in a mixture of ethanol and aqueous hydrochloric acid. Thermal decomposition in hot xylene of the diazonium tetrafluoroborate, formed with sodium nitrite in aqueous fluorboric acid, provided 2,4,7-tri-fluoro-5-methyl-9H-fluorenone. Treatment of the ketone with potassium cyanide and ammonium carbonate in ethanol at 120° C. for 18 hours provided the title compound.
EXAMPLE XXXI
The Synthesis of 2,4,7-trifluoro-5-methoxyspiro(9H-fluorene-9,4'-imidazolidine)-2',5'-dione ##STR157##
2,4,7Trifluoro-5-methoxy-9H-fluorene
A solution of 5-amino-2,4,7-trifluoro-9H-fluorene (10.0 g, 0.042 mol) in 30 mL of tetrahydrofuran was added to 100 mL of 6 M aqueous sulfuric acid. This solution was cooled to 0° C. and sodium nitrite (1.1 eq, 0.046 mol, 3.3 g), dissolved in small volume of water, was slowly added. After having stirred at 5° C. for 1 h, the mixture was added dropwise to 100 mL of 3M aqueous sulfuric acid at 100° C. The resulting mixture was heated at 100 C. for an additional 10 min, allowed to cool, and extracted with ethyl acetate. The ethyl acetate extracts were dried over MgSO 4 and concentrated to leave 10 g of a dark oil which was dissolved in a mixture of 15 mL tetrahydrofuran and 100 mL of 2M aqueous sodium hydroxide. The solution was heated to 40° C. and dimethyl sulfate (1eq, 5.2 g, 4.1 mL) was added slowly. After the addition was complete, the solution was heated to 50° C. and another 0.5 eq of dimethyl sulfate was added. After 1 h at 50° C., the solution was cooled to room temperature and extracted with 50 ml of ethyl acetate. The ethyl acetate extract was washed with water and brine, dried over MgSO 4 , and concentrated to leave 9.0 g of a dark solid which was chromatographed on silica gel using 20% ethyl acetate in hexane to provide 4.8 g (45% ) of the fluorene.
2,4,7-Trifluoro-5-methoxy-9H-fluoren-9-one
Sodium dichromate dihydrate (2 eq, 0.26 mol, 7.9 g) was added to a solution 2,4,7-trifluoro-5-methoxy-9H-fluorene (3.3 g, 0.013 mol) in 100 mL of acetic acid and the mixture was refluxed for 5 h. The cooled reaction mixture was poured into water and extracted with ethyl acetate. The ethyl acetate extract was washed with saturated aqueous sodium bicarbonate and water, dried over MgSO 4 , and concentrated to leave 3 g of a yellow solid which was chromatographed on silica gel using 15% ethyl acetate in hexane to provide 2.0 g (57%) of the fluorenone: mp 164°-166° C.
2,4,7-Trifluoro-5-methoxyspiro(9H-fluorene-9,4'-imidazolidine)2',5'-dione
A mixture of 2,4,7-trifluoro-5-methoxy-9H-fluoren-9-one (2.0 g, 7.6 mmol), potassium cyanide (3 eq, 23 mmol, 1.5 g), and ammonium carbonate (4e.g., 30 mmol, 2.9 g) in 50 mL of ethanol was heated in a sealed bomb at 115° C. for 24 h. After the bomb was cooled and opened, the solvent was evaporated and the residue dissolved in 1M aqueous sodium hydroxide. The basic solution was extracted with ethyl acetate to remove base insoluble impurities and then acidified using concentrated hydrochloric acid. The acidic solution was extracted with ethyl acetate and the extracts were dried over MgSO 4 and concentrated to leave 1.2 g of a brown solid. Chromatography on silica gel using 45% ethyl acetate in hexane provided 500 mg (20%) of the spirohydantoin: mp 227°-229° C.
Analysis calculated for C 16 H 9 F 3 N 2 O 3 : C,57.49; H, 2.71; N, 8.38. Found: C,57.68; H, 2.81; N, 8.34.
EXAMPLE XXXII
Synthesis of 2,4,5,7-Tetrafluorospiro (9H-fluorene-9,4'-imidazolidine-2',5'-dione
Experimental details for the four-step synthesis of 2,4,5,7-tetraflourospiro (9H-fluorene-9,4'-imidazolidine-2',5'-dione from 3,5-difluorobrobromobenzene are provided. Also included is a procedure for the preparation of palladium acetate from the palladium metal which is recovered from the last step and recycled. ##STR158##
3,3'5,5'-Tetrafluorodiphenylcarbinol
A 22-L flask equipped with a mechanical stirrer, a 2-L addition funnel, an efficient condenser, and a bottom drain was dried under a stream of dry nitrogen overnight and then charged with magnesium turnings (90.1 g, 3.790 mol) and anhydrous ether (2 L). A portion (200 mL) of a solution of 3,5-diflurobromobenzene (650.0 g 3.37 mol) (Note 1) in 1500 mL of ether was added and the mixture was heated to reflux. A small amount (˜3 g) of difluorophenylmagnesium bromide (prepared in a test tube) wad added to initiate the reaction. When the reaction mixture turned gray and cloudy, the heating mantle was turned off as the exothermic reaction maintained reflux temperature. Shortly afterwards the mixture turned down and a vigorous reaction set in. After this subsided, the remaining difluorobromobenzene solution was added at a rate which maintained a steady reflux (required 2 hrs) (Note 2). After the addition was complete, the mixture was refluxed for 30 min before the heat was turned off and a solution of ethylformate (125.0 g, 1.69 mol) in ether (1.5 L) was added at a rate that maintained a gentle reflux. The mixture was then refluxed for another hour before it was quenched by the addition of 6 L 20aqueous hydrochloric acid. The aqueous layer was removed and the organic layer was washed twice with water, dried over MgSO 4 , filtered, and concentrated to leave 427 g of a dark brown, viscous oil. The oil was distilled using a short path, large bore distillation apparatus to provide 217 g (50%) of a pale yellow solid (Notes 3 and 4): bp 108°-115° C./0.06 mmHg; mp 61°-64° C.; MS m/z 256 (M + ), 141 (base peak); 1 H NMR (CDCl 3 )δ6.82-6.42 (m, 6); 5.62 (d, 1); 2.18 (d, 1); IR (KBr) 3300 (broad), 1615, 1592 1115 cm -1 .
Notes
1. The 3,5-difluorobromobenzene was purchased from Yarsley Chemical Company.
2. In order to avoid an uncontrollable reaction, it is essential that the grignard reaction be well established (as evidenced by the formation of the brown color) before a large volume of aryl bromide is added.
3. At the expense of yield, colorless material can be obtained by a more careful distillation.
4. Subsequent oxidation attempts using the crude alcohol resulted in a product which was very difficult to isolate and purify.
3,3',5,5'-Tetrafluorobenzophenone
In a 22-L flask equipped with a mechanical stirrer and thermometer, 3,3',5,5'-Tetrafluorodiphenylcarbinol (404 g, 1.58 mol) was dissolved in 3 L of glacial acetic acid. Sodium dichromate dihdyrate (471 g, 1.58 mol) was added in one portion, forming a dark brown solution and an exothermic reaction which caused the temperature to rise to 60° C. within 30 min and maintained that temperature for 15 min. When the temperature began to fall, TLC analysis indicated that the reaction was complete (Note 1). Water (˜10 L) was added to the reaction and the precipitate was collected by filtration, washed with water until the washings were colorless, and dried in the funnel. The white solid was then dissolved in ethyl acetate (˜4 L), washed with water (2×2.5 L), dried over MgSO 4 , filtered, and evaporated to dryness to provide 358 g (89%) of the ketone which was used in the next step without further purification: mp 84°-87° C.; MS m/z 254 (M+); 1 H NMR (CDCl 3 ) δ 7.28-6.80 (m, 6); IR (KBr) 3080, 1670, 1582, 1115, 975, 745 cm -1 .
Note
1. A sample was added to water and extracted with ethyl acetate. The ethyl acetate solution was spotted on a silica gel plate and developed using 20% ethyl acetate/hexane. The R f of the starting material is 0.6 while that of the product is 0.8.
5,5-Di(3,5-difluorophenyl)-2,4-imidazolidinedione
A mixture of 3,3',5,5═-tetrafluorobezophenone (358 g, 1.41 mol), potassium cyanide (137.5 g, 2.11 mol), ammonium carbonate (406 g, 4.22 mol) and ethanol (3.5 L) was heated at 115° C. for 16 h in a stirred 2 gal pressure reactor. After chilling to relieve the pressure, the reactor was opened and the mixture was poured into 8 L of water in a 22-L flask equipped with a mechanical stirrer. The mixture was acidified (pH 2.0) using concentrated hydrochloric acid (˜1 L) (Note 1) and the resulting precipitate was collected by filtration, washed with water, and pressed dry. The crude material was recrystallized from ethanol (˜6 L) to provide 399.5 g (87%) of 5,5-di(3,5-difluorophenyl)-2,4-imidazolidinedione (Note 2): mp 271°-274° C.; MS m/z 324 (M+); 1 H NMR (DMSO-d 6 ) δ 9.50 (s, 2); 7.42-6.90 (m, 6); IR (KBr) 3265, 3160, 3060, 1762, 1710 cm -1 .
Analysis calcd. for C 15 H 8 F 4 N 2 O 2 : C, 55.57; H, 2.49; N, 8.64. Found: C, 55.55; H, 2.38; N, 8.62.
Notes
1. This step should be carried out cautiously in an efficient hood since hydrogen cyanide is formed. The acidification is done slowly to control the vigorous foaming.
2. Recrystallization of the product simplifies the work-up procedure of the following reaction.
2,4,5,7-Tetrafluorospiro(9H-fluorene-9,4'-imidazolidine)-2',5═-dione
A solution of 5,5-di(3,5-difluorophenyl)-2,4-imidazolidinedione (240 g, 0.74 mol) and palladium(II) acetate (167.8 g, 0.748 mol) in 2.4 L of a 50% mixture (v/v) of glacial acetic acid and 69%-72% perchloric acid in a 5-L flask equipped with a mechanical stirrer and a thermometer was heated at 120° to 135° C. for 1.5 h. The reaction mixture was filtered hot through a fritted glass funnel and the black palladium metal was washed well with hot acetic acid. The combined filtrate and washings were poured into 10 L of water and the precipitate was collected by filtration, washed with water, and dried in the funnel. The crude solid was then dissolved in boiling acetonitrile, treated with decolorizing carbon, filtered through celite, and concentrated to 3 L. The solution was slowly cooled to room temperature and then in the refrigerator as the product crystallized. The white crystals were collected by filtration, washed with acetonitrile, and dried to provide 167 g (70%) of 2,4,5,7-tetrafluorospiro (9H-fluorene-9,4'-imidazolidine-2',5'-dione. A second recrystallization gave 150 g of pure compound: mp 287°-290° C.; MS m/z 322 (M+), 251 (base peak); 1 H NMR (DMSO-d 6 ) δ 8.73 (s, 2), 7.52-7.49 (m, 4); IR (KBr) 3340-3160 (broad), 1772, 1722, 1122 cm -1 .
Anal. calcd. for C 15 H 6 F 4 N 2 O 2 : C, 55.91; H, 1.88; N, 8.69; Found: C, 55.65; H, 1.96; N, 8.70.
EXAMPLE XXXIII
The Synthesis of 2,4,5,7-Tetrafluorospiro(9H-fluorene-9,5'-thiazolidine)-2',4'-dione
Experimental details for the four step synthesis of 2,4,5,7-Tetrafluorospiro(9H-fluorene-9,5'-thiazolidine)-2',4'-dione from 2,4,5,7-tetrafluorofluorene are provided. ##STR159##
Methyl 2,4,5,7-Tetrafluorofluorene-9-carboxylate
Under nitrogen, n-butyllithium (5.6 mL of a 2.5M hexane solution) was added dropwise, to a -78° C. solution of the 2,4,5,7-tetrafluorofluorene in gold label THF (80 mL) over 2 min. After 20 min, the mixture was poured onto a slurry of dry-ice (10 g) in anhydrous ether. The solvents were evaporated and the residue was dissolved in methanol (200 mL) and acidified with acetyl chloride (5 mL). After stirring for 18 h, the reaction was concentrated and the residue was diluted with saturated aqueous sodium bicarbonate (200 mL) and extracted with ethyl acetate (3×100 mL). The combined organics were washed with brine (3×100 mL), dried (MgSO 4 ), and evaporated. The residue was chromatographed on silica gel using petroleum ether to provide 2.1 g (57%) of product: 1 H NMR (DMSO-d 6 , 200 MHz) δ 7.44 (dd, 2 H, J=2.2 and 8.3 Hz), 7.40-7.25 (m, 2 H), 5.37 (s, 1 H), 3.76 (s, 3 H).
Methyl 9-Chloro-2,4,5,7-tetrafluorofluorene-9-carboxylate
A solution of methyl 2,4,5,7-tetrafluorofluorene-9-carboxylate (1.49 g, 5.03 mmol) in dry THF (15 mL) was added over 14 min to a stirred, room temperature suspension of unwashed sodium hydride (1.25 eq, 6.29 mmol, 250 mg of a 60% oil dispersion) in THF (15 mL). The mixture was then cooled in an ice water bath and after 9 min a solution of N-chlorosuccinimide (1.2 eq, 6.04 mmol, 810 mg) was added over 14 min. After slowly warming to room temperature, the mixture was stirred for 21 h before it was poured into 100 mL of water and extracted with ethyl acetate. The extracts were washed with aqueous sodium carbonate, aqueous sodium bisulfate, and brine, dried (MgSO 4 ), and concentrated to leave 1.4 g of crude material. Chromatography on silica gel using 20% ethyl acetate in hexane provided 970 mg (58%) of nearly pure material: 1 H NMR (CDCl 3 ) δ 7.20 (dd, 2 H), 7.0-6.6 (m, 2 H), 3.75 (s, 3 H); IR (KBr) 1730, 1600, 1580, 1410, 1105 cm -1 ; MS m/z 330 (M+), 271 (base peak).
2,4,5,7-Tetrafluorospiro(9H-fluorene-9,5'-thiazolidine)-2'-imino-4'-one
A mixture of methyl 9-chloro-2,4,5,7-tetrafluorofluorene-9-carboxylate (970 mg, 2.94 mmol), thiourea (1.1 eq, 3.23 mmol, 250 mg), and sodium acetate (0.75 eq, 2.20 mmol, 180 mg) in acetic acid (8 mL) was refluxed for 8 h. The mixture was cooled to room temperature and the precipitate was collected by filtration, washed with acetic acid and ether, and air dried to provide 440 mg of crude material: MS m/e 338 (M+), 268 (base peak).
2,4,5,7-Tetrafluorospiro(9H-fluorene-9,5'-thiazolidine)-2',4'-dione
Crude 2,4,5,7-tetrafluorospiro(9H-fluorene-9,5'-thiazolidine)-2'-imino-4'-one (440 mg) was refluxed in a mixture of 8 mL each of methanol and concentrated hydrochloric acid for 4 h. After the mixture cooled to room temperature, 8 mL of water was added and the white solid was collected, washed with cold water, and dried to provide 180 mg of crude product. Chromatography on silica gel using a gradient of 1% to 10% methanol in chloroform provided 90 mg of the thiazolidine dione: 1 H NMR (DMSO-d 6 , 200 MHz) δ 7.78 (dd, 2 H, J=2.2 and 8.0 Hz), 7.52-7.41 (m, 2 H); IR (KBr) 1750, 1700 cm -1 ; MS m/z 339 (M+), 268 (base peak).
Anal. calcd for C 15 H 5 F 4 NO 2 S: C, 53.10; H, 1.49; N, 4.13. Found: C, 52.88; H, 1.58; N, 4.00.
EXAMPLE XXXIV
The Preparation of 2,7-difluoro-3-methylspiro(9H-fluorene-9,4'-imidazolidine)-2',5'-dione ##STR160##
Methyl 2-(3-methyl-4-fluorophenyl)-5-fluorobenzoate
A mixture of 4-fluoro-3-methylphenylboronic acid (6.5 g, 42.5 mmol), methyl 2-bromo-5-fluorobenzoate (10.0 g, 42.9 mmol), tetrakis (triphenylphospine) palladium(0) (1.0 g, 0.87 mmol, 0.2 eq), toluene (100 mL), 2M aqueous sodium carbonate (50 mL) and ethanol (25 mL) was refluxed for 9 h. The reaction mixture was then poured into 50 mL each of concentrated ammonium hydroxide, 2M aqueous sodium carbonate, and water, the organic phase was separated, and the aqueous was extracted with ethyl acetate. The combined organics were washed with brine, dried over MgSO 4 , and concentrated to leave an oil which was chromatographed on silica gel using hexane to provide 11 g (98%) of the ester.
Methyl 2-(3-methyl-4-fluorophenyl)-5-fluorobenzoic acid
Potassium hydroxide (6 g) and water (50 mL) were added to a solution of methyl 2-(3-methyl-4-fluorophenyl)-5-fluorobenzoate (10.2 g, 40.0 mmol) in methanol (150 mL) and the mixture was stirred at room temperature for 18 h. The reaction mixture was then evaporated to near dryness, acidified with 1N aqueous hydrochloric acid, and extracted with ethyl acetate. The combined extracts were washed with brine, dried over MgSO 4 , and concentrated to leave a residue which was chromatographed on silica gel using 30% ethyl acetate in hexane to provide 9.7 g of the acid.
2,7-Difluoro-3-methyl-9H-fluorenone
A stirred mixture of methyl 2-(3-methyl-4-fluorophenyl)-5-fluorobenzoic acid (6.5 g, 26.2 mmol) and polyphosphoric acid (30 g) was heated at 180° C. for 2 h. After the mixture had cooled to 80° C., it was poured into water (200 mL), and extracted with ethyl acetate. The combined extracts were washed with brine, dried over MgSO 4 , treated with charcoal, and concentrated. Chromatography on silica gel using 20% toluene in hexane provided 2 g (33%) of the desired ketone.
2,7-Difluoro-3-methylspiro(9H-fluorene-9,4'-imidazolidine)-2',5'-dione
A mixture of 2,7-difluoro-3-methyl-9H-fluorenone (1.8 g, 7.8 mmol), potassium cyanide (2.0 g, 31.2 g, 4 eq), and ammonium carbonate (2.2 g, 23.4 mmol, 3 eq) in 60 mL of ethanol was heated in a sealed bomb at 115° C. for 24 h. The cooled bomb was opened, and the excess potassium cyanide was destroyed with 1M aqueous hydrochloric acid. The mixture was then partitioned between 1M aqueous sodium hydroxide (150 mL) and ethyl acetate (200 mL) and the basic aqueous phase was removed. The organic phase was extracted with 1M sodium hydroxide and the combined basic phases were acidified and extracted with ethyl acetate. The combined extracts were washed with brine, dried over MgSO 4 , and concentrated. The residue was recrystallized from ethanol/water to provide 290 mg of pure hydantoin: mp>315° C.
Analysis calculated for C 16 H 10 F 2 N 2 O 2 : C, 64.00; H, 3.36; N, 9.33. Found: C, 64.05; H, 3.35; N, 9.35.
EXAMPLE XXXV
Synthesis of 2,7-Difluoro-4-methylspiro(9H-fluorene-9,4'-imidazolidine)-2',5'-dione
The preparation of 2,7-difluoro-4-methylspiro(9H-fluorene-9,4'-imidazolidine)-2',5'-dione from ethyl 2-(2-methyl-4-fluorophenyl)-5-fluorobenzoate is described. ##STR161##
Ethyl 2-(2-Methyl-4-fluorophenyl)-5-fluorobenzoate
Tetrakis(triphenylphosphine)palladium(0) (0.02 eq, 0.31 g) was added to a vigorously stirred solution of ethyl 2-bromo-5-fluorobenzoate (1.0 eq, 3.3 g, 0.013 mol) and 2-methyl-4-fluorophenylboronic acid (1.2 eq, 0.016 mol, 2.4 g) in 45 mL of toluene, 22 mL of 2M aqueous sodium carbonate, and 11 mL of ethanol and the mixture was refluxed for 9 h. The cooled reaction mixture was poured into 50 mL each of water, ammonium hydroxide, and 2M aqueous sodium bicarbonate and then filtered through Celite. The filtrate was extracted with ethyl acetate and the organics were dried (MgSO 4 ) and concentrated to yield 3.9 g of a yellow oil. Chromatography (silica gel, 20% ethyl acetate/hexane) gave 3.4 g (92%) of product as a light colored oil. 1 H NMR (CDCl 3 , 60 mHz) δ 7.7 (dd, 1 H), 7.5 (m, 1 H), 7.25- 6.75 (m, 4 H), 4.0 (q, 2 H), 2.0 (s, 3 H), 1.0 (t, 3 H); IR (CDCl 3 solution) 3130, 2220, 1700, 1450, 1080 cm -1 ; MS m/z 276 (M+), 201 (base peak).
2-(2-Methyl-4-fluorophenyl)-5-fluorobenzoic acid
A solution of methanol (15 mL), water (10 mL), potassium hydroxide (2 eq, 1.2 g), and ethyl 2-(2-methyl-4-fluorophenyl)-5-fluorobenzoate (1.0 eq, 3.4 g) was allowed to stir at room temperature for 16 h. The reaction was then concentrated in vacuo and the residue dissolved in 20 mL of water. Acidification with concentrated hydrochloric acid resulted in the precipitation of the product as a white solid. The solid was collected by filtration, dissolved up in ethyl acetate, washed with water, and then dried over magnesium sulfate. Concentration of the ethyl acetate solution left 3.2 g of product as a white solid. MS m/z 248 (M+), 201 (base peak).
2,7-Difluoro-4-methyl-9-fluorenone
2-(2-Methyl-4-fluorophenyl)-5-fluorobenzoic acid (3.2 g, 0.013 mol) was placed in 40 g of polyphosphoric acid and heated at 210° C. for 1.5 h. The reaction was allowed to cool and was then poured into 200 mL of ice water. Ethyl acetate and 1N aqueous sodium hydroxide (100 mL each) were added and the solution was filtered through celite. The organic layer was separated and the aqueous layer was extracted once again with 75 mL of ethyl acetate. The combined organics were washed with saturated aqueous sodium bicarbonate and water, dried (MgSO 4 ), and concentrated in vacuo leaving 1.9 g of product as a yellow solid. Recrystallization from ethanol gave 1.5 g (52%) of pure product: mp 172°-175° C.; 1 H NMR (CDCl 3 , 60 mHz) δ 7.6-6.7 (m, 5 H), 2.5 (s, 3 H); IR (KBr) 1700, 1460, 1280, 775 cm -1 ; MS m/z 230 (M+). Analysis Calculated for C 14 H 8 OF 2 : C, 73.04; H, 3.50. Found: C, 72.93; H, 3.67.
2,7-Difluoro-4-methylspiro(9H-fluorene-9,4'-imidazolidine)-2',5'-dione
2,7-Difluoro-4-methyl-9-fluorenone (1.3 g, 0.0056 mol), potassium cyanide (3 eq, 0.017 mol, 1.1 g), ammonium bicarbonate (3 eq, 0.017 mol, 1.3 g), and 50 mL of ethanol were placed in a sealed bomb and heated at 125° C. for 20 h. The bomb was cooled to room temperature and the contents were filtered through Celite washing with water and ethyl acetate. The filtrate was concentrated in vacuo and the residue was dissolved in 40 mL of 1N aqueous sodium hydroxide and washed with ethyl acetate (2×30 mL). The aqueous solution was acidified with concentrated hydrochloric acid and the product extracted into ethyl acetate. The organic solution was then dried and concentrated providing 1.1 g of a crude white solid which was recrystallized from ethanol to give 340 mg of 2,7-difluoro-4-methylspiro(9H-fluorene-9,4'-imidazolidine)-2',5'-dione: mp >320° C.; 1 H NMR (DMSO-d 6 , 60 mHz) δ 8.5 (s, 1 H), 7.8 (m, 1 H), 7.2 (m, 4 H), 2.7 (s, 3 H); IR (KBr) 3300, 1710, 1380, 770 cm -1 ; MS m/z 300 (M+), 229 (base peak). Analysis Calculated for C 16 H 10 F 2 N 2 O 2 ·1/2 H 2 O: C, 62.14; H, 3.58; N, 9.06. Found: C, 62.21; H, 3.58; N, 8.81.
EXAMPLE XXXVI
Synthesis of 2,7-Difluoro-4-methoxyspiro(9H-fluorene-9,4'-imidazolidine)-2',5'-dione
The preparation of 2,7-Difluoro-4-methoxyspiro(9H-fluorene-9,4'-imidazolidine)-2',5'-dione from 2,7-difluoro-4-aminofluorene is described. ##STR162##
2,7-Difluoro-4-methoxy-9H-fluorene
A solution of 2,7-difluoro-4-amino-9H-fluorene, (10 g, 0.046 mol) in 20 mL of tetrahydrofuran was added to 100 mL of 6M aqueous sulfuric acid. This yellow solution was cooled to 0° C. and sodium nitrite (1.0 eq, 3.6 g), dissolved in a small volume of water, was slowly added. The temperature was kept below 5° C. throughout the addition and was kept at 0° C. for 1 h afterward. The reaction was then added to a 100° C. 3M aqueous sulfuric acid solution. The temperature of the hot acid solution was controlled by the rate of addition and was not allowed to go below 85° C. After complete addition, the reaction was stirred for 2 minutes at 100° C. and then allowed to cool to room temperature. The aqueous solution was extracted with ethyl acetate (2×20 mL) and the combined extracts were dried (MgSO 4 ), filtered through a small pad of silica gel, and concentrated in vacuo. The residue was dissolved in 100 mL of 2N aqueous sodium hydroxide and heated to 45° C. Dimethyl sulphate (1.0 eq, 4.5 mL) was then added dropwise. The solution was kept basic and at 45° C. throughout the addition. Another portion of dimethyl sulphate (0.5 eq., 2.3 mL) was added and the solution was heated to 50° C. for 30 minutes. The cooled solution was extracted with ethyl acetate (2×50 mL) and the extracts were dried (MgSO 4 ), treated with carbon, filtered, and concentrated to give a crude black solid. The solid was stirred in 500 mL of hexane and the insoluble material filtered off. Concentration of the hexane solution gave 6.8 g of a crude yellow solid. Chromatography (silica gel, 10% ethyl acetate in hexane) gave 6.3 g (58%) of product as a yellow crystalline solid: 1 H NMR (CDCl 3 , 60 MHz) δ 7.9 (dd, 1 H), 7.2-6.3 (m, 4 H), 3.9 (s, 3 H), 3.7 (s, 2 H); IR (KBr) 1590, 1450, 1120, 830 cm -1 ; MS m/z 232 (M+).
2,7-Difluoro-4-methoxy-9H-fluorenone
2,7-Difluoro-4-methoxy-9H-fluorene (4 g, 0.017 mol), sodium dichromate dihydrate (1.1 eq, 5.7 g) and 50 mL of acetic acid were heated to 50° C. for 1 h. No change was observed on TLC (30% ethyl acetate/hexane) so the temperature was raised to 75° C. and held there for 3 h. The reaction was then poured into water and extracted with ethyl acetate. The organic solution was washed with aqueous sodium bicarbonate, dried (MgSO 4 ), and concentrated in vacuo to give 3.8 g of a yellow solid. Recrystallization of the solid from ethanol gave 1.1 g of pure product. (The rest of the material was identified as starting material): 1 H NMR (CDCl 3 , 60 MHz) δ 7.5 (dd, 1 H), 7.2-6.6 (m, 4 H), 3.9 (s, 3 H); IR (KBr) 1700, 1450, 1300, 780 cm -1 ; MS m/z 246 (M+).
2,7-Difluoro-4-methoxyspiro(9H-fluorene-9,4'-imidazolidine)-2',5'-dione
2,7-Difluoro-4-methoxy-9H-fluorenone (1.1 g, 0.004 mol), potassium cyanide (1.5 eq, 0.007 mL, 0.44 g), ammonium carbonate (3.0 eq, 0.014 mol, 1.3 g) and 25 mL of ethanol were placed in a sealed bomb and heated at 115° C. for 24 h. The cooled reaction mixture was poured into a boiling flask and concentrated in vacuo. The residue was dissolved in ethyl acetate and the solution was washed with 1N aqueous hydrochloric acid, treated with carbon, dried (MgSO 4 ), filtered, and concentrated to give 1.5 g of an off-white solid. The solid was dissolved in 1N aqueous sodium hydroxide, filtered through Celite, and acidified with concentrated hydrochloric acid. The white precipitate was collected and recrystallized from ethanol. The still impure product was chromatographed (silica gel, 10% acetone/hexane) to give 300 mg of pure 2,7-difluoro-4-methoxyspiro(9H-fluorene-9,4'-imidazolidine)-2',5'-dione; 1H NMR (CDC13, 200 MHz) & 11.3 (s, 1 H, exchangeable), 8.66 (s, 1 H, exchangeable), 7.88 (dd, 1 H, J=5.2 and 8.5 Hz), 7.44 (dd, 1 H, J=2.3 and 8.5 Hz), 7.29 (ddd, 1 H, J=2.5, 8.5, and 9.5 Hz), 7.08 (dd, 1 H, J=2.1 and 11.6 Hz), 7.03 (dd, 1 H, J=2.1 and 8.0 Hz), 3.98 (s, 3 H); IR (KBr) 1700, 1450, 1190, 830 cm -1 ; MS m/z 316 (M+), 71 (base peak).
Analysis calculated for C 16 H 10 F 2 N 2 O 3 : C, 60.76; H, 3.19; N, 8.86. Found: C, 60.65; H, 3.19; N, 8.86.
EXAMPLE XXXVII
Synthesis of 3,7-Difluoro-9-methylspiro[5H-indeno[1,2-b]pyridine-5,4'-imidazolidine]-2',5'-dione
The four-step synthesis of 3,7-Difluoro-9-methylspiro[5H-indeno[1,2-b]pyridine-5,4'-imidazolidine]-2',5'-dione from ethyl 2-(2-methyl-4-fluorophenyl)-5-fluoro-3-pyridinecarboxylate is described. ##STR163##
Ethyl 2-(2-methyl-4-fluorophenyl)-5-fluoro-3-pyridinecarboxylate
Tetrakis(triphenylphosphine)palladium(0) (0.02 eq, 0.89 g) was added to a vigorously stirred solution of ethyl 2-chloro-5-fluoro-3-pyridinecarboxylate (0.038 mol, 7.8 g) and 2-methyl-4-fluorophenylboronic acid (1.5 eq, 0.057 mol, 8.9 g) in 100 mL of toluene, 50 mL of 2M aqueous sodium carbonate, and 25 mL of ethanol and the mixture was refluxed for 9 h. The cooled reaction mixture was poured into 100 mL each of water, ammonium hydroxide, and 2M aqueous sodium carbonate and then filtered through Celite. The filtrate was extracted with ethyl acetate and the organics were dried (MgSO 4 ) and concentrated to yield 12 g of a red oil. Chromatography (silica gel, 20% ethyl acetate/hexane) gave 9.7 g (92%) of product as a light colored oil: 1 H NMR (CDCl 3 , 60 MHz) δ8.7 (d, 1 H), 8.0 (dd, 1 H), 7.1-6.8 (m, 3 H), 4.1 (q, 2 H), 2.0 (s, 3 H); MS m/z 277 (M+).
2-(2-Methyl-4-fluorophenyl)-5-fluoro-3-pyridinecarboxylic Acid
A solution of methanol (100 mL), water (10 mL), potassium hydroxide (2 eq, 4.0 g), and ethyl 2-(2-methyl-4-methyl-4-fluorophenyl)-5-fluoro-3-pyridinecarboxylate (1.0 eq, 9.6 g) was allowed to stir at room temperature for 16 h. The reaction was then concentrated in vacuo and the residue dissolved in 80 mL of water. Acidification with concentrated hydrochloric acid did not result in precipitation of product so the product was extracted out with ethyl acetate. Drying (MgSO 4 ) and concentration of the organics left 8.5 g (99%) of product as an off-white solid: 1 H NMR (CDCl 3 , 60 MHz) δ 9.7 (s, 1H), 8.7 (d, 1 H), 8.0 (dd, 1 H), 7.1-6.8 (m, 3 H), 2.0 (s, 3 H); MS m/z 249 (M+), 204 (base peak).
3,7-Difluoro-9-methyl-5H-indeno[1,2-b]pyridin-5-one
2-(2-methyl-4-fluorophenyl)-5-fluoro-3-pyridinecarboxylic acid (8.5 g, 0.034 mol) was placed in 102 g of polyphosphoric acid and heated at 210° C. for 3 h. The reaction was allowed to cool and was then poured into 500 mL of ice water. Ethyl acetate and 1N aqueous sodium hydroxide (200 mL each) were added and the solution was filtered through Celite. The organic layer was separated and the aqueous layer was extracted with ethyl acetate (2×75 mL). The combined organics were washed with saturated aqueous sodium bicarbonate and water, dried (MgSO 4 ), and concentrated in vacuo leaving 4.0 g of a greenish solid. Recrystallization from ethanol/ethyl acetate with carbon treatment gave 2.1 g of clean product: mp 155°-157° C.; 1 H NMR (CDCl 3 , 60 MHz) δ 8.3 (dd, 1 H), 7.4 (dd, 1 H), 7.2-6.8 (m, 2 H), 2.7 (s, 3 H); IR (KBr) 1730, 1470, 1280, 785 cm -1 ; MS m/z 231 (M+), 203 (base peak); Analysis calculated for C 13 H 7 NOF 2 : C, 67.54; H, 3.05; N, 6.06. Found: C, 67.20; H, 3.20; N, 5.76.
3.7-Difluoro-9-methylspiro[5H-indeno[1,2-b]pyridin-5,4'-imidazolidine]-2'5'-dione
3,7-difluoro-9-methyl--5H-indeno[1,2-b]pyridin-5-one (2.0 g, 0.0087 mol), potassium cyanide (2.5 eq, 0.022 mol, 1.4 g), ammonium carbonate (4 eq, 3.3 g), and 50 mL of ethanol were placed in a sealed bomb and heated to 115° C. for 24 h. The bomb was cooled to room temperature and the contents were filtered through Celite washing with water and ethyl acetate. The filtrate was concentrated in vacuo and the residue was dissolved in 50 mL of 1N aqueous sodium hydroxide and washed with ethyl acetate (2×30 mL). The aqeuous solution was acidified with concentrated hydrochloric acid and extracted with ethyl acetate (2×50 mL). The organics were dried (MgSO 4 ) and concentrated in vacuo to give 600 mg of a crude tan solid. Recrystallization from ethanol gave 250 mg of pure product: mp>320+ C.; 1 H NMR (DMSO-d 6 , 200 MHz) δ 11.42 (s, 1 H, exchangeable), 8.66 (s, 1 H, exchangeable), 8.60 (m, 1 H), 8.17 (dd, 1 H, j=2.7 and 8.2 Hz), 7,.37 (dd, 1 H, J=2.3 and 8.2 Hz), 7.24 (dd, 1 H, J=1.7 and 10.3 Hz), 2.79 (s, 3 H); IR (KBr) 3200, 1710, 1390, 1130 cm -1 ; MS m/z 301 (M+); Analysis calculated for C 15 H 9 F 2 N 3 O 2 : C, 59.81; H, 3.01; N, 13.95. Found: C, 59.86; H, 3.17; N, 13.67.
EXAMPLE XXXVIII
General Procedure for the Synthesis of 3,7-difluoro-9-methylspiro[5H-indeno[1,2-b]pyridin-5,3'-pyrrolidine]2',5'-dione ##STR164##
Treatment of 3.7-difluoro-9-methyl-5H-indeno]1,2-b]pyridin-5-one with hydrazine in hot diethylene glycol provided 3,7-difluoro-9-methyl-5H-indeno[1,2-b]pyridine. Deprotonation using n-butyllithium in tetrahydrofuran followed by reaction with carbon dioxide and methanolic hydrogen chloride provided 3,7-difluoro-9-methyl-5H-indeno[1,2-b]pyridin-5-carboxylic acid methyl ester. The ester was then deprotonated using a slight excess of sodium hydride in tetrahydrofuran and treated with iodoacetamide to provide, after 18 hours at room temperature and 6 hours at reflux, the title compound.
Of special interest according to the present invention are tetrasubstituted compounds of the formula: ##STR165## wherein t is selected from the group consisting of NH, O, S and CHR' wherein R' is hydrogen or lower alkyl of 1 to 5 carbon atoms. Especially preferred compounds are thos where the fluoro and methoxy substitents are located in the ring in meta position to each other.
An especially preferred compound is 2,7-difluoro-4,5-dimethoxyspiro (9H-fluorene-9,4'-imidazolidine)-2',5'-dione of the formula: ##STR166##
This compound is a very potent aldose reductase inhibitor with an IC 50 value of 0.78×10 -8 Mol/L. The IC 50 value is based on the inhibition of rat lens aldose reductase.
The above compounds are prepared from trifluoro-5-hydroxyfluorenone by reaction with alkali metal alkoxide in a solvent such as dimethyl formamide followed by alkyl iodide to provide the difluoro-dialkoxyfluorenone in good yield. Subsequent conversion to the hydantion can be carried out using standard Bucherer-Bergs conditions as described herein to produce the desired product in good yield.
EXAMPLE XXXIX
2,7-Difluoro-4,5-Dimethoxyfluorenone
A mixture 2,4,7-trifluoro-5-hydroxyfluorenone (2.5 g, 10 mmol) and sodium methoxide (6 mL of a 25% solution in methanol, 3 eq) in dry dimethylformamide (80 mL, over sieves) was stirred under nitrogen at room temperature. After 2 h, additional sodium methoxide (6 mL of a 25% solution in methanol, 3 eq) was added. Stirring was continued for 2 h at which time the mixture was treated with iodomethane (15 mL, 46 mmol 4.6 eq) over 20 min. The reaction became a deep red and was then diluted with water (300 mL), neutralized with 1N aqueous hydrochloric acid, and filtered, washing with water. The solid was dissolved in warm ethyl acetate (500 mL), dried (MgSO 4 ), treated with carbon (Norit A), filtered through celite, and concentrated. The residue was recrystallized from ethyl acetate.hexane to provide 2.2 g (80%) of product as a red solid: mp 185°-187° C.; IR (KBr) 1722.0, 1615.3, 1487.4 cm -1 : 1 H NMR (CDCIl 3 ,200 MHz) δ 6.99 (dd, 2 H, J=2.3, 6.4 Hz), 6.76 (dd, 2 H, J=2.3, 10.7 Hz), 3.90 (s, 6 H); MS m/z 376 (M+). Anal calcd for C 15 H 10 F 2 O 3 : C, 65.22; H, 3.65. Found: C, 65.31, H, 3.79.
EXAMPLE XXXX
2,7-Difluoro-4,5-dimethoxyspiro (9H-fluorene 9,4'-imidazolidine)-2',5'-dione
A mixture of 2,7-Difluoro-4,5-dimethoxy fluorenone (1.5 g, 5.3 mmol), potassium cyanide (1.4 g, 21.2 mmol, 4 eq) and ammonium carbonate (1.5 g, 15.9 mmol, 3 eq) in 70 mL of ethanol was heated in a sealed bomb at 114° C. for 18 h. The bomb was then cooled and the mixture partitioned between 1N aqueous sodium hydroxide (100 mL) and a 1:1 mixture of ethyl acetate/hexane (100 mL). The basic aqueous phase was separated and the organic phase was extracted with 1N aqueous sodium hydroxide (3×74 mL). The combined basic aqueous layers were washed with ether (2×100 mL), dried (MgSO 4 ), treated with carbon (Norit A), filtered through celite, and concentrated to provide 1.37 g (70%) of crude material. This material was combined with an additional 425 mg of crude material obtained in the same fashion and first leached with ethanol and then crystallized from ethanol to provide 1.5 g (58%) of product as a white solid; mp>326° C.; IR (KBr) 3328.6, 1779.3, 1715.1, 1607.4 cm -1 ; 1 H NMR (DMSO d 6 , 200 MHz) δ 11.24 (a, 1 H, D 2 o exchangeable), 8.64 (s, 1 H, D 2 O exchangeable), 6.96 (m,4 H), 3.87 (s, 6 H); MS m/z 346 (M+), base peak 275. Anal calcd for C 17 H 12 N 2 O 4 F 2 : C, 58.96; H, 3.49; N, 8.09. Found: C, 59.01; H, 3.59; N, 8.09. | Disclosed are substituted or unsubstituted planar tricyclic fluorene or nuclear analogs thereof, spiro-coupled to a five-membered ring containing a secondary amide, and the pharmaceutically acceptable salts thereof. These compounds are useful, inter alia in the treatment of diabetes. Also disclosed are processes for the preparation of such compounds; pharmaceutical compositions comprising such compounds; and methods of treatment comprising administering such compounds and compositions when indicated for, inter alia, long term, prophylactic treatment of the diabetes syndrome. A particularly preferred class of compounds comprise difluoro-dialkoxy substituted spiro-(9H-fluorene-9,4'-imidazolidine)-2,40 ,5-diones. | 2 |
FIELD OF THE INVENTION
The present invention relates generally to wireless digital devices; and more particularly to wireless user input devices to communicate with computers.
BACKGROUND OF THE INVENTION
There are many user input devices for use with a digital computer, including standard keyboards, touchpads, mice and trackballs. Wireless communication technology has advanced rapidly over the past few years and there has been rapid development of wireless technologies for providing communication between input/output devices and their “host” computers. For example, wireless keyboards and mice now couple via wireless connections to their host computers. These “wireless” input devices are highly desirable since they do not require any hard-wired connections with their host computers. However, the lack of a wired connection also requires that the wireless input devices contain their own power supply, i.e., that they be battery powered.
In order to extend the life of its batteries, a wireless input device often supports power saving modes of operation. For example, the wireless input device may include circuitry to provide for various levels of power-down modes to reduce power consumption when the device is inactive. When activity is detected, the interface circuitry transitions to a power-up mode to facilitate communications between the user interface device and the computer and then returns to a power-down mode after a predetermined interval of inactivity of the user interface device.
However, when the wireless input device is unintentionally activated, for example when an object is accidentally placed on the wireless input device, the wireless input device is forced back to the power-up mode and starts consuming substantial power. This results in a significantly reduced battery life for the wireless input device.
Thus, there is a need in the art for a method and apparatus for reducing power consumption of a wireless input device when the wireless input device is unintentionally activated.
SUMMARY OF THE INVENTION
The present invention provides an improved method and apparatus for reducing power consumption of a wireless input device when the wireless input device is unintentionally activated, and thereby significantly reduces the amount of power needed to operate the associated circuitry over an extended period of time.
In one embodiment, the present invention is directed to a method and apparatus for reducing power consumption of a wireless input device when the wireless input device is unintentionally activated. An unintentional activation of the wireless input device is detected; power consuming circuitry of the wireless input device is disabled responsive to the detection; a removal of the unintentional activation of the wireless input device is detected; and the power consuming circuitry of the wireless input device for normal operation is enabled.
BRIEF DESCRIPTION OF THE DRAWINGS
The objects, advantages and features of this invention will become more apparent from a consideration of the following detailed description and the drawings, in which:
FIG. 1 is an exemplary system diagram illustrating a PC host and a wireless keyboard that includes a detection means, according to one embodiment of the present invention;
FIG. 2 is an exemplary schematic block diagram illustrating the structure of a wireless keyboard that includes a wireless interface device constructed, according to one embodiment of the present invention;
FIG. 3 is an exemplary block diagram illustrating a wireless interface device, according to one embodiment of the present invention;
FIG. 4 is an exemplary block diagram illustrating a processing unit of a wireless interface, according to one embodiment of the present invention;
FIG. 5 is an exemplary block diagram illustrating an input/output unit of a wireless interface, according to one embodiment of the present invention;
FIG. 6 is an exemplary state diagram illustrating operation, according to one embodiment of the present invention;
FIG. 7 is an exemplary illustration of the keyboard scan circuit components according to one embodiment of the present invention;
FIG. 8 is an exemplary timing diagram illustrating operation of the keyboard matrix circuitry operating, according to one embodiment of the present invention;
FIG. 9 is an exemplary flowchart representation of a process to reduce power consumption of a wireless input device when the wireless input device is unintentionally activated, according to one embodiment of the present invention;
FIG. 10A is an exemplary diagram of an edge detection circuit, according to one embodiment of the present invention; and
FIG. 10B is an exemplary timing diagram illustrating operation of the exemplary edge detection circuit of FIG. 10B .
DETAILED DESCRIPTION
In one embodiment, the present invention is directed to a method and apparatus for reducing power consumption of a wireless input device when the wireless input device is unintentionally activated. When, for example, a key in a wireless keyboard is confirmed accidentally pressed, a detection logic coupled to keyboard row inputs is enabled and is used to detect a transition of the row inputs to the opposite state. The power consuming circuitry (e.g., key scan block, control logic, and the related clocks) of the wireless input device is then turned off. When the opposite state is detected by for example, an asynchronous logic, the power consuming circuitries are turned back on and the wireless input device resumes its normal operation. Although, the specification uses a wireless keyboard, and mouse as examples for a wireless input device, the described embodiments below are not limited to wireless keyboards and mouse. Other wireless input devices, such as microphones, sensors, etc. are well within the scope of the present invention.
Preferably, the detection logic is asynchronous. In this case, the detection logic consumes a negligible amount of power. In addition to negligible amount of power consumption, the present invention has a low latency because there is no running clock involved in the asynchronous logic.
FIG. 1 is a system diagram illustrating a personal computer (PC) host 106 and a wireless input device (e.g., keyboard 108 ) that includes a wireless interface device and detection means, according to one embodiment of the present invention. The wireless input device is battery powered and operates for extended periods of time on a single set of batteries because of the reduced power consumption operations according to the present invention.
FIG. 2 is a schematic block diagram illustrating the structure of a wireless keyboard matrix 203 that operates in conjunction with a wireless interface device (e.g., an integrated circuit 202 ), according to one embodiment of the present invention. As shown in FIG. 2 , wireless interface device 202 services a key scan matrix 203 that provides inputs from the keyboard. The wireless interface device 202 couples to a battery 204 , a crystal 206 , an EEPROM 208 , and an antenna 216 . Indicators 205 include number, capitals, and scroll lights that are lit on the keyboard.
In another embodiment (not shown in FIG. 2 ), an integrated circuit services both mouse and keyboard input and may reside internal to either the mouse or the keyboard. In this embodiment, as will be apparent to those skilled in the art, multiplexing or signal sharing may be required, because the input signals differ. However, different signal lines may be dedicated for keyboard and for mouse inputs such that no signal sharing is required.
FIG. 3 is a block diagram illustrating a wireless interface device, according to one embodiment of the present invention. As shown in FIG. 3 , the wireless interface device 202 includes a processing unit 302 , a wireless interface unit 304 , an input/output unit 306 , and a power management unit 308 . The wireless interface unit 304 couples the wireless interface device 202 to antenna 216 . In a power down mode (explained below), the power management unit 308 operates voltage regulation circuitry of the processing unit (via PU_EN signal) and the wireless interface unit (via WIU_EN signal) to power down the processing unit 302 and wireless interface unit 304 , respectively.
The wireless interface unit 304 can be adapted to operate according to the Bluetooth specification and in particular to the Human Interface Device (HID) portion of the Bluetooth specification. It will be understood by those skilled in the art, however, that the present invention can be adapted to work in conjunction with other wireless interface standards.
Processing unit 302 , wireless interface unit 304 , and input/output unit 306 couple with one another via a system bus 310 . Processing unit 302 includes a processing interface that may be used to couple the processing unit to one or more devices. Input/output unit 306 includes an input/output set of signal lines that couple the wireless interface device 202 to at least one user input device, such as a mouse or a keyboard.
FIG. 4 is a block diagram illustrating a processing unit 302 of the wireless interface device of FIG. 3 . The processing unit 302 includes a microprocessor core 402 , read only memory 406 , random access memory 404 , serial control interface 408 , bus adapter unit 410 , and multiplexer 412 . The microprocessor core 402 , ROM 406 , RAM 404 , serial control interface 408 , bus adapter unit 410 , and multiplexer 412 couple via a local bus. Multiplexer 412 multiplexes an external memory interface between the local bus and a test bus. The bus adapter unit 410 interfaces local bus with the system bus. The microprocessor core 402 includes a universal asynchronous receiver transmitter interface that allows direct access to the microprocessor core. Further, the serial control interface 408 provides a serial interface path to the local bus.
FIG. 5 is a block diagram illustrating the input/output unit 306 of the wireless interface device of FIG. 3 . The input/output unit 306 includes a keyboard scanning block 502 , a mouse quadrature decoder block 504 , and a general purpose input output (GPIO) control block 506 . The GPIO control block 506 is capable of enabling/disabling the input/outputs and control the direction of data, that is as an input or an output, as described below with reference to FIG. 7 .
Each of the keyboard scanning block 502 , the mouse quadrature decoder block 504 , and the GPIO control block 506 couple to the bus. Further, each of the keyboard scanning block 502 , the mouse quadrature decoder block 504 , and the GPIO control block 506 couple to I/O via multiplexer 508 . This I/O couples to at least one user input device.
In another embodiment of the input/output unit 306 , each of the keyboard scanning block 502 , the mouse quadrature decoder block 504 , and the GPIO control block 506 couples directly to external pins that couple to at least one user input device.
FIG. 6 is an exemplary state diagram illustrating operation of the wireless interface device 202 , according to one embodiment of the present invention. As shown, the wireless interface device includes four separate power-conserving modes, a busy mode, a idle mode, a suspend mode and, a power down mode. The state diagram of FIG. 6 shows each of these modes and how each of these modes is reached during normal operation. In one embodiment, the power management unit (e.g., 308 in FIG. 3 ), under control of the processing unit, operates voltage regulation circuitries of the processing unit and the wireless interface unit to operate the four separate power-conserving modes of the wireless interface device 202 .
When the wireless interface device is initially powered up, it enters the busy mode of operation. In the busy mode of operation, all features and wireless operations of the wireless interface device are enabled. As long as I/O activity continues, the wireless interface device remains in the busy mode. However, after expiration of a first timer with no I/O activity, the operation moves from the busy mode to the idle mode. Operation will remain in idle mode until the expiration of a second timer or until I/O activity occurs, as shown.
If I/O activity occurs while in the idle mode, operation returns to the busy mode. When in the idle mode, if timer 2 expires with no additional I/O activity, suspend mode is entered. While in suspend mode, if I/O activity occurs, operation returns to busy mode. However, if no additional I/O activity occurs while in suspend mode before the expiration of a third timer, power down mode is entered. While in the power down mode, operation will remain in the power down mode until I/O activity occurs. When I/O activity occurs, operation of the wireless interface device will move from the power down mode to the busy mode.
FIG. 7 is an illustration of a keyboard switch matrix 1102 connected to a key matrix scan circuit 502 . The keyboard matrix 1102 comprises a plurality of columns 1108 and a plurality of rows 1106 . In the exemplary embodiment shown in FIG. 7 , the plurality of columns 1108 comprises six columns C 0 –C 5 and the plurality of rows comprises four rows, R 0 –R 3 . For simplicity reasons, the embodiment illustrated in FIG. 7 shows only a small portion of an actual keyboard matrix. It is understood by those skilled in the art that the number of rows and columns can be increased or decreased depending on the specific application.
A plurality of switches 1110 connect the respective rows and columns when a corresponding key is pressed by a user. In this example, switch 1110 connects row R 0 and column C 0 when the switch 1110 is pressed. Although a reference numeral has not been provided for each of the switches, it should be understood that a total of 24 switches 1110 are associated with the intersection of the rows and columns in FIG. 7 . For purposes of discussion, the twenty-four illustrative switches 1110 in FIG. 7 are referred to as Switch 1 , Switch 2 , . . . , Switch 24 . When all of the respective switches in a particular row are open, the row is pulled “high” by resistor 1112 that is connected to Vdd. Rows R 0 –R 3 provide inputs to row decoder 1120 in the key matrix scan circuit 502 , as will be discussed in greater detail below.
Key matrix scan circuit 502 comprises column/row control logic 1114 and driver logic 1115 that generate appropriate signals to control the state of the respective columns and rows. Driver logic 1115 comprises a tri-state driver 1116 and a buffer 1118 . The column/row control logic 1114 generates appropriate “high” and “low” signals that are provided to the inputs of the tri-state drivers 1116 . The column/row control logic can change the state of a particular row or column by generating appropriate “enable” signals that control the operation of the tri-state drivers 1116 in the control logic 1115 . For example, if the input of the tri-state driver 1116 is “high,” the generation of an enable signal will cause the tri-state driver 1116 to apply the “high” signal at its output to drive the column or row “high.” Conversely, if the input to the tri-state driver 1116 is “low,” the generation of an enable signal will cause that tri-state driver to drive the column or row “low.” The enable signals can be global enable signals intended to enable the tri-state drivers for all rows, e.g. ENB_R, or for all columns, e.g. ENB_C. The enable signals also can be directed to a tri-state driver for a particular row, e.g. ENB_R 1 , or for a particular column, e.g. ENB_C 3 .
The key matrix scan circuit 502 also comprises row decoder 1120 and column decoder 1122 that are operable to decode output signals received from the respective rows and columns in the keyboard matrix 1102 . The decoded output signals from the row decoder 1120 and the column decoder 1122 are provided to scan logic 1124 which generates a data stream indicating the state of various switches (keys) 1110 .
The key matrix scan circuit 502 also comprises a switch transition detection circuit 1126 that receives output signals from the row decoder 1120 and the column decoder 1122 . The switch transition detection circuit 1126 is communicatively coupled to the scan logic 1124 which scans the various rows and columns as described hereinbelow. In addition, the switch transition detection circuit 1126 generates an “I/O Active” signal that is provided to the input/output unit 306 (in FIG. 3 ) to cause the system to transition into the “busy” mode as described above.
Operation of the keyboard scan circuitry can be understood by referring to the timing diagram of FIG. 8 . Referring to FIG. 8 , the initial state of all of the rows and columns is analyzed beginning at the “Ready” reference line. The transitions to the left of the “Ready” reference are provided simply to clarify the “high” or “low” status of the rows and columns when processing begins. Beginning at the “Ready” reference point, ENB_C is high (active) and all columns are driven low by the tri-state drivers 1116 . All of the rows are pulled high via the resistors 1112 shown in FIG. 7 .
If, as an example, Switch (Key) # 9 is pressed, R 0 transitions from “high” to “low.” This transition is used as a trigger to latch (store) all row values. This transition also causes ENB_C to transition from “high” to “low.” Since ENB_C is “low,” the columns are no longer being driven and, therefore, R 0 transitions back to “high.” The actual transition of R 0 to “high” will be delayed somewhat by the RC constant combination of the line capacitance of column C 2 and the resistor 1112 . Since switch # 9 is still pressed, the column C 2 will transition to “high.” The “low” to “high” transition of column C 2 is used as a trigger to latch all column values. After the column values have been latched, ENB_C transitions from “low” to “high” and column C 2 transitions from “high” to “low.” All other columns are also maintained in the “low” state since ENB_C is now high (active).
In the example shown in FIG. 8 , there is one high latched column value (C 2 ) and one low latched row value (R 0 ). The single latched column and the single latched row uniquely identify a single key switch (switch # 9 ) and, therefore, there is no need to enter into a “scan” of other rows and columns. Thus the scan signal remains “low” during the entire cycle.
The column/row control logic 1114 , in conjunction with the driver logic 1115 , is operable to generate all of the control signals necessary to control the state transitions described above. Furthermore, the switch transition detection circuit 1126 is operable to generate a “I/O Active” signal for the input/output unit 406 immediately upon receiving an output signal from the row decoder 1120 and/or the column decoder 1122 indicating that a switch has been activated. In this example the “I/O Active” signal is generated immediately by the switch transition detection circuit 1126 immediately upon detection of the transition of row R 0 from “high” to “low” as a result of switch # 9 being activated.
Now, if an object, such as a book, is unintentionally placed on the keyboard (or a mouse), activating a key, such as key # 9 , the system returns to the busy mode (in FIG. 6 ), for example, from power down mode. The system then activates all of the control logic shown in FIG. 7 and starts transmitting the key information to the host (e.g., processor unit 302 of FIG. 3 ). As a result, the battery life of the wireless keyboard would substantially suffer.
FIG. 9 is an exemplary flowchart representation of a process to reduce power consumption of a wireless input device when the wireless input device is unintentionally activated, according to one embodiment of the present invention. In block 902 , an unintentional activation of the wireless input device, for example, an object-on-a-key, is detected. Activation of the key (or several keys) is first detected by the methods described above. If the same key (or keys) remain activated for a predetermined amount of time, for example, more than few milliseconds that takes a typical key activation for a normal operation, an object-on-a-key is detected. This may be implemented by a timer that starts timing upon activation of the key. The timer function is well known in the art and may be implemented in the power management unit (e.g., as a counter) or the processing unit (e.g., as a software timer or hardware counter).
Upon detection of an object-on-a-key, the power consuming circuitry, such as control logic, related clocks and other related circuitry are disabled to save power consumption of the wireless input device, as shown in block 904 . In one embodiment, the processing unit detects the object-on-a-key and then disables the control logic and clocks via the power management unit that controls the voltage regulation circuitries of the processing unit and the wireless interface unit. In one embodiment, if the processing unit has a power saving mode (e.g., idle mode), the processing unit may also be disabled (e.g., via the power management unit).
In block 906 , removal of the unintentional activation of the wireless input device (e.g., the object from the key) is detected. In one embodiment, when the object is removed from the key(s), an edge in the timing of the corresponding row(s) is detected. The detected edge then causes the processing unit to enable the control logic and clocks, as shown in block 908 . If the processing unit is in a power saving mode, the detected edge “wakes” the processing unit (e.g., via an interrupt) and the processing unit enables the control logic and clocks.
FIG. 10A illustrates an exemplary circuit, and FIG. 10B depicts the related timing diagram of an asynchronous detection logic, according to one embodiment of the present invention. It is understood by those skilled in the art that a similar synchronous detection logic may be used. However, a synchronous detection logic consumes more power than an asynchronous detection logic, when in an idle mode. In one embodiment, the asynchronous detection logic is included in the power management unit, which controls the voltage regulation circuitries of the processing unit and the wireless interface unit to power down the processing unit and wireless interface unit, respectively. In another embodiment, the asynchronous detection logic may be included in the input/output unit which sends a detection signal to the power management unit to control the voltage regulation circuitries of the processing unit and the wireless interface unit.
In one embodiment, the detection circuit is a basic asynchronous flip-flop that has a Row_i signal as its input, an object-on-a-key signal as its enable input. The Data input is tied to the power supply (Vdd). This way, the flip-flop is capable of detecting an edge transition of the Row_i input and producing a high (or a low) logic at its output. In one embodiment, this flip-flop is implemented using CMOS technology. In this embodiment, when the flip-flop is not detecting any edges, it only consumes power proportional to the leakage currents of its internal (NMOS and PMOS) transistors. Since, the leakage currents are very small, the power consumption of this flip-flop is also very small, when not detecting edges.
Referring now to FIG. 10B , at time A, a key is pressed, resulting in a high-to-low transition of the Row_i signal, as described above with reference to FIG. 7 . A timer is started for measuring duration of the activation of the key. If this duration is more than a predetermined amount of time, for example, more than about seventy milliseconds for a normal operation, an object-on-a-key is identified (detected), at time B. Subsequently, the key scan and related logic is disabled to reduce power consumption of the key board, resulting in a low-to-high transition of the Row_i signal at time C, due to pull-up resistors 1112 shown in FIG. 7 . A generated object-on-a-key signal enables the edge detection flip-flop, as shown in FIG. 10A .
At this time, if the processing unit is not disabled as a result of the power saving mode of the key board, the processing unit causes the Row_i signal to transition back to a low state, at time D. However, if the processing unit is disabled as the result of the power saving, a “flag” signal generated by the low-to-high transition of the Row_i signal at time C, causes the Row_i signal to transition back to a low state, at time D. When the object is removed from the keyboard, Row_i signal transitions again from a low to a high state at time E, as explained above with reference to FIG. 7 . This low-to-high transition is detected by the flip-flop. As a result of this removal detection, the disabled power consuming circuits are enabled and resumed for normal operation. Also, the flip-flop is now cleared, using a signal generated after the removal detection.
It will be recognized by those skilled in the art that various modifications may be made to the illustrated and other embodiments of the invention described above, without departing from the broad inventive scope thereof. It will be understood therefore that the invention is not limited to the particular embodiments or arrangements disclosed, but is rather intended to cover any changes, adaptations or modifications which are within the scope and spirit of the invention as defined by the appended claims. | An improved method and apparatus for reducing power consumption of a wireless input device when the wireless input device is unintentionally activated, and thereby significantly reduces the amount of power needed to operate the associated circuitry over an extended period of time.
In one embodiment, an unintentional activation of the wireless input device is detected; power consuming circuitry of the wireless input device is disabled responsive to the detection; a removal of the unintentional activation of the wireless input device is detected; and the power consuming circuitry of the wireless input device for normal operation is enabled. | 8 |
SPECIFICATION
[0001] This application claims the benefit of U.S. provisional application Ser. No. 61/954,154, filed Mar. 18, 2014.
FIELD OF THE INVENTION
[0002] The present invention relates to a separator unit for separating oil and water produced from oil wells.
BACKGROUND OF THE INVENTION
[0003] in addition to oil, oil wells typically produce unwanted fluids such as water. As fluid is produced to the surface by the well, it is desirable to separate water from the oil at the well site, before the oil is transported or sold.
[0004] In the prior art, separator units and storage tanks are brought to the well site. This involves loading the separator unit onto a truck and trucking the unit to the well site. Likewise, storage tanks are loaded onto one or more additional trucks and the tanks are trucked to the well site. The separator unit and storage tanks are typically oversized. As a result, when trucked to the well site, special procedures are followed, such as using escorts warn motorists of the wide load. All of these trucks and special procedures add to the cost of transporting the equipment to and from the well site.
[0005] Once delivered to the well site, the separator unit is located relative to the well and the storage tanks are located relative to the well and the separator unit. Lines running from the well to the separator unit are plumbed, as are lines from the separator unit to the storage tanks. The setup and installation of the equipment is time consuming and laborious. Once installed, the well is produced into the separator unit and the water is stored in a storage tank. The oil is stored in a separate storage tank.
[0006] Thus, it is expensive to provide a well site with a separator and separate storage tanks for oil and water. Included in the cost is not lust the equipment, but the cost of installation and removal of the equipment. In some wells, the cost of such equipment may be too expensive relative to the production of the wells. For example, in small stripper wells, small quantities of oil are produced. Such wells may produce large amounts of water relative to oil and thus be in need of a separator and storage. Yet, the cost of installing and removing the equipment ma be prohibitively high.
[0007] There is a need for a less expensive, less labor intensive, and more ecological reflective designed portable test separator unit.
SUMMARY OF THE INVENTION
[0008] A towable separator unit for oil wells, comprises a chassis, wheels rotatable mounted to the chassis so the chassis can be towed and a walled enclosure supported by the chassis. The enclosure has top, bottom, exterior side and end walls, the walled enclosure having interior side walls arranged so as to form a first tank, a second tank and a third tank, each of the first, second, and third tanks capable of holding a fluid without leaking. An inlet pipe is structured and arranged to connect to an oil well, the inlet pipe communicating with the first tank so as to deliver fluids from the oil well into the first tank. A first transfer pipe has an inlet located in a bottom region of the first tank. The first transfer pipe having an outlet located in one of the second or third tanks, the first transfer pipe located interiorly of the walled enclosure. A second transfer pipe has an inlet located in a top region of the first tank, the second transfer pipe having an outlet located in the other of the second or third tanks, the second transfer pipe sloped downwardly from its inlet to its outlet. Each of the second and third tanks having an outlet.
[0009] In accordance with one aspect, the first, second and third tanks are arranged longitudinally inside the walled enclosure, with the second tank between the first and third tanks.
[0010] In accordance with another aspect, the top wall of the walled enclosure has a step down portion that is stepped down from the first tank to the third tank the second transfer pipe is located exterior to the stepped down portion of the top wall, further comprising a valve in the exterior portion of the second transfer pipe.
[0011] In accordance with another aspect, the inlet pipe is connected to a flume located in the first tank, the flume extending vertically from the top wall toward the bottom wall, the flume having a lower portion with openings therein to allow the well fluid to enter the first tank, further comprising a perforated coalescer above the flume openings.
[0012] In accordance with another aspect, the first transfer pipe comprises a water leg.
[0013] In accordance with another aspect, the third tank has plural outlets arranged vertically along the third tank.
[0014] In accordance with another aspect, further comprising a level sensor in at least one of the first, second or third tanks, the level sensor providing liquid level information to a display on the exterior of the walled enclosure.
[0015] In accordance with another aspect, further comprising a wireless transmitter connected to the level sensor to provide level information remotely from the well.
[0016] In accordance with another aspect, the level sensor measures the level of oil and also measures the level of water in the respective tank.
[0017] In accordance with another aspect, wherein the inlet of the second transfer pipe comprises a stub removably connected to the second transfer pipe and having a length so as position the inlet of the second transfer pipe at a predetermined location above the bottom W all of the first tank.
[0018] In accordance with another aspect, the unit is road legal.
BRIEF DESCRIPTION OF THE DRAWINGS
[0019] FIG. 1 shows the separator unit at a well site, connected to a well.
[0020] FIG. 2 is a side view of the separator unit, in accordance with a preferred embodiment.
[0021] FIG. 3 is a top view of the separator unit.
[0022] FIG. 4 is a rear end view of the separator unit.
[0023] FIG. 5 is a front end view of the separator unit.
[0024] FIG. 6 is a partial cross-sectional side view of the separator unit.
[0025] FIG. 7 is a side elevational view of the flume.
[0026] FIG. 8 is a side elevational view of the water leg.
[0027] FIG. 9 is a detailed side elevational view of the inlet to the oil transfer pipe.
[0028] FIG. 10 is a schematic view of a level sensor.
[0029] FIG. 11 is a block diagram of the sensor system.
[0030] FIG. 12 shows a liquid level sensor in accordance with another embodiment.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0031] FIG. 1 shows an oil well site with an oil well 11 . The oil well is a stripper well that produces a small quantity of fluid on a daily basis. Much of the fluid produced is oil, but a quantity of water is also produced. In order to separate the oil, and the water and store both types of separated fluids, a separator unit 15 is used.
[0032] The separator unit 15 is portable and fully self-contained. It is suitable for being towed on roads and simple to install and make ready for operation. Once in operation, the separator unit 15 is reliable with no active components such as pumps. Much of the plumbing is internal where it is protected from freezing and being damaged when the unit is towed on the road. Because little work needs to be done to set up and remove the separator unit 15 from a well site, the unit is safer to install and remove and is also safe to operate.
[0033] When no longer needed, the separator unit 15 can easily be disconnected and towed off of the well site and reused at another well site.
[0034] The separator unit 15 (see FIG. 2 ) is a self-contained trailer, having a chassis frame 17 , wheels 19 and a towing hitch 21 . The trailer has a front end 23 near the hitch, and a rear end 25 near the wheels 19 .
[0035] In addition, the separator unit has three tanks or compartments, namely an oil-water tank 27 (see FIG. 6 ), a water tank 29 and an oil tank 31 . Each tank has a floor 33 , a top 35 and exterior side walls 37 . The exterior side walls 37 are corrugated. Each tank is provided with an access hatch 38 in the respective side wall. There are also interior side walls 39 , 41 between the tanks. The oil-water tank 27 shares a side wall 39 with the water tank 29 . The water tank 29 shares a side wall 41 with the oil tank 31 . The interior surfaces of the tanks are epoxy coated.
[0036] In the preferred embodiment, the oil-water tank 27 is located at the rear end 25 , the oil tank 31 at the front end 23 and the water tank 29 between the other two tanks. The oil-water tank and oil tank are about the same volume, while the water tank is smaller in volume, in the preferred embodiment. The relative sizes of the tanks can be changed to suit the particular needs of the well site. By way of example only, the oil-water tank can be 210 barrels, the oil tank 214 barrels and the water tank 150 barrels.
[0037] The top 35 of the unit is stepped down from the rear end 25 to the front end 23 . The top of the oil water tank 27 is higher than the tops of the other two tanks 29 , 31 . The top of the water tank 29 is stepped down 79 at a location between the interior side walls 39 , 41 (see FIG. 6 ). Steps 43 or a ladder can be provided at the front end 23 (see FIGS. 2 and 5 ) to allow personnel to access the top 35 . The rear end 25 is equipped with lights 45 so that the trailer can legally travel on roads ( FIG. 4 ).
[0038] An inlet pipe 47 is connected to the oil-water tank 27 . The inlet pipe 47 is connected to the well 11 , either directly, or indirectly by way of equipment such as a gas separator. The inlet pipe 47 extends along the exterior of the rear end 25 and along the top 35 of the oil-water tank 27 to a vertical pipe or flume 49 . Referring to FIG. 7 , the flume 49 has an exterior or upper, portion 51 and an interior, or lower, portion 53 . The interior portion 53 is a pipe that extends from the top 35 to the floor 33 of the oil-water tank 27 . The top end of the pipe extends above the tank top 35 for a short distance. The pipe has cutouts or openings 54 in its tower end to allow the liquid in the pipe to escape into the tank 27 . A spreader 55 , or coalescer, is provided a distance above the floor 33 . The spreader is located above the openings 54 . The spreader 55 is attached to and extends out horizontally from the pipe. The spreader 55 is a perforated plate or mesh and could be made of expanded metal. The spreader can be a flat plate. If so, then the plate is provided with a downwardly depending skirt 56 that extends around the circumference of the plate. Alternatively, the plate can be domed, with the outer edges lower than the center. Thus, the oil and water is retained under the spreader for a period of time to allow the oil to coalesce. The lower portion of the flume 49 is located in the center of the lowest part of the tank 27 .
[0039] The upper portion 51 stands up from the top 35 of the tank. The upper portion 51 is hinged 57 or otherwise movably coupled to the lower portion 53 top end. When the separator unit 15 is being transported, the upper portion 51 is laid down as shown b) dashed lines in FIG. 7 in order to reduce the overall height of the unit. As an alternative, the upper portion 51 can be completely removed and stowed in a bracket on the side of the unti in order to lower the overall height of the unit. Handles can be provided on the upper portion to assist in moving the portion into place. On installation, the upper portion 51 is raised to a vertical position and is secured to the lower portion 53 with one or more clamps. A gasket between the upper and lower portions provides a seal. The connection is preferably a quick release clamp with a single bolt. This is in contrast to a typically pipe flanged connection with a number of bolts. The quick release clamp saves time in setup and take-down. The inlet pipe 47 is connected to the upper portion 51 . The inlet pipe 47 has a flexible portion 47 A that extends from the top wall to the flume top 51 to accommodate the flume top 51 moving about the hinge.
[0040] Water is transferred from the oil-water tank 27 to the water tank 29 by way of a water leg 59 (see FIG. 8 ). The water leg 59 has an upside down “U” shape and is located in the oil-water tank 27 . Thus, there are two vertical pipes 61 joined together by a horizontal pipe 63 which is located some distance above the floor 33 . One end of one of the vertical pipes 61 is open 65 to the oil-water tank 27 and is located close to the floor 33 . The other vertical pipe 61 joins to a horizontal pipe 67 which passes through the side wall 39 into the water tank 29 where it is open. A vertical riser 69 extends from one of the vertical pipes 61 above the top 35 . A weather cover can be provided over the open riser 69 .
[0041] Oil is transferred from the oil-water tank 27 to the oil tank 31 by an oil transfer pipe 71 . The inlet 73 to the pipe 71 is located near the top 35 of the oil tank 27 (see FIG. 9 ). The height of the inlet 73 above the floor 33 can be adjusted by adding or subtracting the lengths of vertical pipe stubs 75 . For example, adding a pipe stub 75 on top of the pipe creates an inlet 73 A that is higher relative to the floor 33 . The stubs 75 can be threaded into the pipe 71 . An access hatch 77 is provided on the top 35 in order to access the inlet 73 (see FIG. 3 ).
[0042] The oil transfer pipe 71 exits through the side wall 39 , extends along the upper portion of the water tank 29 for a distance and exits the water tank at the step down partition 79 . The pipe 71 continues along the top exterior toward the front end 33 where it enters the oil tank 31 at the top. The pipe is sloped down from the oil-water tank to the oil tank. A valve 81 is provided, which valve is accessed from the top 35 of the unit.
[0043] An overflow and skim oil pipe 83 is provided between the water tank 29 and the oil tank 31 . The overflow pipe 83 (see FIGS. 3 and 6 ) has an inlet near the top of the water tank 29 and extends out of the water tank at the step down 79 . The pipe 83 then enters the top of the oil tank 31 . The pipe 83 is provided a valve 85 , accessible from the top. Personnel can use the stairs 43 to climb on top and access the valves 81 , 85 as well as access hatches.
[0044] One or more tanks 27 , 29 , 31 are provided with level sensors 87 (see FIG. 10 ). The sensors are conventional and commercially available. A tube 89 extends vertically inside the respective tank through the top down to the bottom or floor. A toroid float 91 can travel along the tube and tracks the liquid level 92 . As the float 91 moves, its position is detected by magnetic sensors inside the tube. In addition, the temperature of the fluid can be sensed by the unit. Electronic package 93 is located on top of the tube and sends the level and temperature information to a display 95 ( FIGS. 11 ), which is mounted at the front end 23 ( FIG. 5 ).
[0045] Referring to FIG. 11 , the level sensors 87 report to a monitor 97 which electronically monitors the levels. If a level in a tank exceeds a predetermined level, the monitor 97 initiates an alarm. The alarm is provided on the display and is also sent offsite by a wireless communications link, such as a satellite link (or cellular telephone link). A receiver 99 located offsite receives the alarm. The receiver can be a cellular telephone or smartphone. The system allows offsite personnel to monitor the status of the unit 15 to minimize overflow from the tanks. In addition to sending alarm information, the system can also send status updates on the liquid levels and temperatures. These can be sent on a periodic basis. The system can include a GPS (global positioning system) unit 100 . For example, the monitor and transmitter 97 can include a GPS unit 100 , wherein the location of the separator unit 15 is transmitted to the receiver 99 . The GPS unit 100 allows the separator unit 15 to be leased on a per location basis. If the unit is moved to another location outside of the terms of the lease (and without permission of the owner), the owner will know that the lease has been violated.
[0046] FIG. 12 illustrates another embodiment of a liquid level sensor 109 . A vertical tube 111 is provided from the top wall 35 to the bottom 33 . The tube has a longitundinal slot therein to allow liquid in the tank to enter the tube at various levels. Alternatively, the tube can be provided with a series of slots or openings along the length of the tube to admit liquid therein. Inside the tube are two floats that move along the length of the tube interior. One float 113 is on top of the oil 115 , while the other float 117 is on top of the water 119 . Also inside of the tube 111 are magnetic sensors 121 that sense the positions of the two floats 113 , 117 . The magnetic sensors are connected to the electronic package 93 .
[0047] The sensor 109 is used in a tank having both oil and water. For example, one sensor 109 can be used in the oil-water tank 27 while another sensor 109 is used in the oil tank 31 . The water tank 29 can be provided with the sensor 109 , however typically the water tank contains little or no oil.
[0048] As the levels of liquid 115 , 119 vary, the respective floats 113 , 117 move along inside the tube, with the oil float 113 following the oil level 115 and the water float 117 following the water level 119 . The positions of the floats are sensed by the sensors 121 , which are read by the electronics package 93 and sent to the display 95 and the receiver 99 .
[0049] The water and oil tanks 29 , 31 have takeoff valves in the respective side walls 37 . The water tank 29 takeoff valve 101 (see FIG. 6 ) is located near the floor or bottom of the tank. The valve 101 allows a hose to be connected thereto so that water in the tank can be loaded into a truck for transport offsite.
[0050] The oil tank 31 has a number of takeoff valves 103 (see FIG. 5 ) vertically staggered and located at the front end 23 . Thus, the valves allow a user to sample the liquid inside at various vertical positions or vertical levels inside the tank. The oil inside the oil tank 31 is typically marketable. However, there may be some water located at the bottom. When an operator arrives to offload oil, the operator can open the various valves 103 to determine where the bottom level of the marketable oil is. For example, the operator can open the bottom valve. If water comes out or a combination of water and oil comes out, the operator knows that there is water at that particular level. The operator can open the next highest valve. If oil comes out of the valve, then the operator knows that oil is located at that level and above. Therefore, the operator would connect the hose to that valve, open a valve to offload the liquid oil for transport offsite.
[0051] In operation, the unit 15 is towed to a well site. The unit is road legal, with lights and with a width and a height that allows it to be taken on public roads and beneath bridges and overpasses. An escort for the towed vehicle need not be provided as the unit 15 is towed on public roads. This saves labor and expense. At the well site, the unit is positioned as desired. The unit is then lowered to the ground; the chassis 17 bears on the ground. The well is connected to the inlet pipe 47 . The exterior portion 51 of the flume 49 is raised to a vertical position and clamped in place in addition, hand rails 105 can be installed on the landing, which hand rails have been taken off and stowed for transport As an alternative, the stairway landing can be lowered so as to lower the overall height of the hand rails 105 , which hand rails can then be permanently attached. Hand rails can be permanently attached along the steps up to the landing. The truck towing the trailer is disconnected and can be used for other jobs. Once connected, the unit is ready for operation and the well can be opened to produce into the unit. Oil and water flow through the inlet pipe 47 and descend into the oil-water tank 27 via the flume 49 . The liquid exits the flume through the openings 54 in the bottom. The water naturally stays at the bottom while the oil rises to the top. The spreader 55 slows the ascent of the oil and serves to coalesce small globules of oil into larger globules, which makes separation more effective. The flume 49 thus slows the velocity of the incoming liquid in order to assist in separation.
[0052] The overall fluid level in the oil-water tank 27 rises as liquid continues to enter. When the level is high enough, water passes from the bottom of the oil-water tank 27 , through the water leg 59 and into the water tank 29 . Likewise, oil enters, the oil transfer pipe 71 near the top of the oil tank 27 and flows into the oil tank 31 . Thus, separation is accomplished automatically.
[0053] Overflow protection and skim oil capability is provided. For example, in the preferred embodiment, the water tank 29 is smaller in volume than the oil tank 31 . If an operator, when onsite, and reading the display 95 , notices the water level in the water tank is high and close to overflowing, the operator can open the valve 85 and allow water to exit the water tank 29 via the overflow pipe 83 into the oil tank 31 . The operator is thus able to prevent a spill, which spill could have environmental consequences. Alternatively, if the water tank were larger than the oil tank, an overflow pipe could be provided, which allows flow from the oil tank into the water tank.
[0054] Although liquid level sensors can be provided in one or more of the tanks 27 , 29 , 31 , sight glasses could be used as an alternative. Such sight glasses however are subject to breakage and, if filled with water, freezing.
[0055] The overflow pipe 83 can be used to transfer skim oil out of the water tank 29 . The skim oil is at the top level of liquid in the water tank. An operator can open the valve 85 to transfer the skim oil out of the water tank 29 into the oil tank 31 .
[0056] The separator unit is easy to install and set up, easy to remove from a well site and low in maintenance. It operates automatically, needing only occasional visits to offload the water and the oil, typically by truck. It is desired for cold climate use, as the water lines are all interior and not subject to freezing.
[0057] The separator unit can be operated and liquid levels monitored by personnel on the ground. Personnel need not climb on top to gauge liquid levels, but can read the levels on the display 95 . The offload valves 101 , 103 are provided at ground level.
[0058] To remove the separator unit 15 from the well site, the well is disconnected by disconnecting the line 47 . Preferably, the tanks 27 , 29 , 31 are emptied into other vessels to reduce the weight of the unit 15 . All protruding objects such as the flume top and handrails are stowed. A towing vehicle is backed to the unit and connected to the trailer hitch 21 . As the unit front end is lifted onto the towing vehicle, the chassis 17 is lifted off the ground and the wheels 19 bear the weight. The unit 15 can now be towed on the wheels 19 . Thus, the unit is both set up and removed simply and quickly, saving on labor and materials.
[0059] The unit 15 is road legal and is not an oversized load. As a result, one or more escorts for transporting the unit along a public road are not required. An example of a road legal load is a width not exceeding 102 inches and a height not exceeding 13 feet 6 inches. The unit 15 is within these dimensions.
[0060] Although the unit 15 can be used as a self-contained separator, in some situations, the unit can be used in conjunction with other equipment. For example, the unit can be used with a separate water tank, if the well produces too much water for the water tank 29 and additional water storage is needed. As another example, the unit 15 can be used with a separate oil tank, to provide additional oil storage on the well site.
[0061] The foregoing disclosure and showings made in the drawings are merely illustrative of the principles of this invention and are not to be interpreted in a limiting sense. | A towable separator unit for oil wells has a walled enclosure with tanks therein. The tanks, which are an oil-water tank, a water tank and an oil tank, are separated from one another by interior side walls. An inlet pipe brings well fluids to the oil-water tank via a flume that allows the contents to enter the tank and be separated. A water leg allows water on the bottom to pass into the water tank; the water leg in contained inside the enclosure so as not to be subject to freezing. An oil outlet pipe allows oil on top of the oil water tank to exit and flow by gravity into the oil tank. The tanks have liquid level sensors therein; the levels are displayed on the outside and are transmitted to a remote location. The water and oil tanks have outlets. The oil tank has plural outlets arranged vertically to allow determination of the water level therein. | 1 |
BACKGROUND OF THE INVENTION
The present invention generally pertains to video detector circuits for radar systems and is particularly directed to enhancing the signal-to-noise ratio and target-to-clutter ratio in a received radar signal prior to signal processing.
A typical video detector circuit essentially includes a detector diode having one of its electrodes connected to an input terminal for detecting an applied RF signal, and its other electrode connected to a load terminal for providing a detected signal; and a load resistance connected between the load terminal and a bias terminal. The operating characteristics of the diode are defined by a curve having a gradual portion in which the diode forward current increases slightly as the diode forward voltage is increased from zero volts, a steep portion in which the diode forward current increases sharply as the diode forward voltage is further increased, and a knee portion defining a transition between the gradual and steep portions. A typical characteristic curve for a diode is shown in FIG. 1.
The applied RF signal typically contains an rms voltage caused by thermal noise and components representative of clutter in addition to target information. Clutter is a term used to describe confusing and unwanted echoes which interfere with detection of the desired target information. Typically clutter may be caused by the ground and by trees, brush and other ground vegetation. The quiescent operating point of the detector diode serves as a dc pedestal level for the target, clutter and thermal noise voltage components which are contained in the applied RF signal.
Typically the bias terminal is at circuit ground potential; and the quiescent operating point of the detector diode is determined by the extent to which the diode is forward biased by the energy content of the applied RF signal. Such a video detector circuit is said to be self-biased. In a self-biased video detector circuit the quiescent operating point of the detector diode is in the steep portion of its characteristic curve. Accordingly when an applied signal which contains an rms noise voltage within a predetermined range is provided across the diode detector in a self-biased video detector circuit, the resultant diode rms noise current is in a range about the quiescent operating point in the steep portion of the characteristic curve, thereby causing the signal-to-noise ratio of the detected signal to be close in value to the signal-to-noise ratio of the applied signal.
SUMMARY OF THE INVENTION
The video detector circuit of the present invention is characterized by providing a dc potential at the bias terminal to forward bias the detector diode to have a quiescent operating point below the midpoint of the knee portion of its characteristic curve, thereby limiting diode rms noise current and components in said detected signal that are representative of clutter. Such a video detector circuit is said to be externally biased. As is explained hereinafter in the Operation and Theory of the Invention portion of the Specification, the limitation of noise and clutter by establishing the quiescent operating point of the detector diode at such point on its characteristic curve enhances the signal-to-noise ratio and the target-to-clutter ratio of the video detector circuit.
The externally biased video detector circuit of the present invention is further characterized by a filter network connected between the load terminal and an output terminal for providing an output signal at the output terminal in which low frequency components representative of clutter in the detected signal are suppressed.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 illustrates a diode characteristic curve showing the relationship of forward current to forward voltage.
FIG. 2 is a schematic circuit diagram of an externally biased video detector circuit according to the present invention.
FIG. 3 is a curve showing the low frequency response of the high pass filter network included in the video detector circuit of FIG. 2.
FIG. 4 is a characteristic curve of the junction resistance for the diode used in the preferred embodiment of the video detector circuit of FIG. 2.
FIG. 5 is a characteristic curve of the junction capacitance for the diode used in the preferred embodiment of the video detector circuit of FIG. 2.
FIG. 6 is an equivalent circuit of the video detector circuit shown in FIG. 2.
FIG. 7 is an ac equivalent circuit of the video detector circuit of FIG. 2.
FIG. 8 illustrates waveform models of radar pulses representative of target and clutter.
FIG. 9 illustrates an ideal square law diode characteristic curve.
FIG. 10 illustrates curves of output signal-to-noise ratio versus detector diode quiescent operating point of an ideal square law diode for different input signal-to-noise ratios.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to FIG. 2, a preferred embodiment of an externally biased diode detector circuit according to the present invention includes a detector diode 10 and a load resistance 12. The diode 10 has its cathode connected to an input terminal 14 and its anode connected to a load terminal 16. The load resistance 12 is connected between the load terminal 16 and a bias terminal 18. A resistance 19 connected between the input terminal 14 and circuit ground provides a dc return path for the diode 10.
The detector diode 10 is a Hewlett Packard No. 5082-2810 diode. The characteristic curve for this diode is shown in FIG. 1.
A positive dc potential +V 1 of 22 volts is provided at the bias terminal 18 to forward bias the diode 10 to have a quiescent operating point on its characteristic curve at the point indicated by the "o" symbol in FIG. 1. At this quiescent operating point the diode forward voltage is approximately 230 millivolts and the diode forward current is approximately 14 microamperes.
The detector diode 10 detects an applied RF signal at terminal 14 and provides a detected signal at terminal 16. The applied RF signal may include target, thermal noise and clutter components. The target components are radar pulses reflected from substantial solid objects. The rise time of a radar pulse representative of a target corresponds to a frequency component of approximately 100 MHz. The clutter components are radar pulses reflected from less substantial objects, such as bushes or foilage. The rise time of a radar pulse representative of clutter corresponds to a frequency of approximately 10 MHz.
The load resistor 12 in combination with the capacitor 20 forms a shunt RC network which functions to integrate the detected radar signal pulses provided at the load terminal 16.
A high pass filter 21 network is connected between the load terminal 16 and an output terminal 22. The high pass filter network 21 includes capacitors 24 and 25, and resistances 26, 27, 28, and 29. The high pass filter network 21 suppresses low frequency components representative of clutter that are included in the detected signal at terminal 16 so that such clutter components are suppressed in the output signal provided at terminal 22. The radar backscatter cross-section of moving clutter, such as vegetation, is a stochastic quantity containing frequency components to a few hundred hertz. The addition of the high pass filter network 21 to the video detector circuit serves to suppress the excursions of the frequency components about the means value of clutter. The low frequency response of the high pass filter network 21 is shown in FIG. 3. The 3 dB corner is at about 4KHz, and the attenuation slope is about 12 dB per octave.
The values of the resistances and capacitances used in the preferred embodiment of the externally biased video detector circuit shown in FIG. 2 are a follows:
______________________________________RESISTANCES12 1.4 megohms19 100 ohms26 11 kilohms27 10 kilohms28 1 kilohm29 1 megohmCAPACITANCES20 118 pf23 1 μf24 .0039 μf25 220 pf______________________________________
OPERATION AND THEORY OF THE INVENTION
The operation and theory of the externally biased video detector circuit of the present invention is explained with reference to the preferred embodiment thereof described above with reference to FIG. 2.
1. Enhancement of Target-to-Clutter Ratio
The detector diode 10 operates at the quiescent operating point "o" on its characteristic curve, as shown in FIG. 1. When a radar pulse in the RF signal applied at the input terminal 14 is detected by the diode 10, the diode is reverse biased, thereby resulting in a displacement of the operating point to some peak value.
The magnitude of the displacement of the operating point from its quiescent value is a function of the energy content of the radar pulse. If the energy content is large, the displacement will be more pronounced. Radar pulses representative of a target usually are narrow, such as 70 nanoseconds wide, for example. Extended ground clutter, however, is received from the entire area of intersection between the antenna beam and the ground. Thus the pulse widths of radar pulse representative of clutter usually are large, such as 1 microsecond, for example. Consequently, ground clutter, which is of the same order of magnitude as the target, will cause a much larger displacement of the operating point than will the target.
The displacement of the operating point of the detector diode 10 from its quiescent value results in changes in the diode junction resistance. The junction capacitance changes very little, remaining at about 1.1 pf. as shown in the characteristic curve for junction capacitance (FIG. 5). But the variation in junction resistance, as shown in the characteristic curve for junction resistance (FIG. 4), is a sensitive function of forward diode current. When the diode 10 is reverse biased by the applied signal, its forward current decreases, and its junction resistance increases.
FIG. 6 shows the equivalent circuit of the externally-biased video detector circuit of FIG. 2. The diode 10 can be represented by a combination of an ideal diode, a capacitor C D , and two resistors R D and R S as shown in FIG. 6. The effect of an increase in junction resistance is a greater influence by the junction capacitance on the impedance of the combined elements. The capacitive reactance, for its part, is a function of the frequency components of the input waveforms, and it will be higher for the radar pulse representative of clutter than for the radar pulse, representative of a target. This is because the rise time of the clutter pulse is longer than the rise time of the target pulse. It now will be shown, by example, that changing the diode impedance by the means described will result in an increased target-to-clutter ratio. Example.
FIG. 7 is the ac equivalent video detector circuit, shown in terms of resistances and capacitive reactances. Its transfer function can be shown to equal: ##EQU1## In FIG. 7, the 1.4 megohm resistor has been omitted because its effect is insignificant. For the same reason, the diode series resistance, which is only about 10 ohms, has been omitted. Input waveform models of radar pulses representative of target and clutter are shown in FIG. 8. They are approximations to the actual values, but their amplitudes have been normalized to unity. The rise time of the target pulse is 10 nanoseconds, so that its frequency response is 100 MHz. The rise time of the clutter pulse is 100 nanoseconds, equivalent to a frequency of 10 MHz. The differences in rise times account for the differences, by a factor of 10, in the values of the reactive components when confronted by a target or clutter.
The values of all the circuit components of the ac equivalent circuit of FIG. 7 are as follows:
__________________________________________________________________________Operating Point (mA) Reactances ResistancesInputQuiescent Peak X.sub.C.sbsb.D X.sub.C.sbsb.2 R.sub.D R__________________________________________________________________________Target.05 1590 13.5 .4 680 5240Target .01 1590 13.5 .4 8000 5240Clutter.05 1590 135 4 680 5240Clutter .01 15900 135 4 8000 5240__________________________________________________________________________
These values were substituted into equation (1) to compute the relative gains of the circuit to target and clutter components for quiescent and peak values of detector bias. These gains are as follows:
______________________________________Waveform Condition V.sub.o /V.sub.i Attenuation______________________________________Target Quiescent 65 -5.9 dBTarget Peak .33Clutter Quiescent .063 -21.3 dBClutter Peak .0054______________________________________
It is seen that target amplitude decreases by 5.9 dB, whereas clutter amplitude is reduced by 21.3 dB. The improvement in target-to-clutter ratio, therefore, is 15.4 dB.
2. Signal-to-Noise Ratio Enhancement
A typical quiescent operating point of a detector diode, such as the diode 10, in a self-biased video detector circuit is indicated by the "x" symbol on the diode characteristic curve of FIG. 1. It is situated on the steep portion of the curve, and therefore, any applied rms noise voltage produces a moderately large rms noise current. Lowering the quiescent operating point by externally biasing the video detector circuit in accordance with the present invention, as shown by the "o" symbol on the curve of FIG. 1, results in a smaller rms noise current range for the same rms noise voltage as is applied to the self-biased video detector circuit. If the quiescent operating point is lowered sufficiently, clipping of negative-going (relative to the pedestal) rms noise voltage by the action of the diode 10 produces an additional reduction in the noise current.
In the externally-biased video detector circuit of the present invention, the components in the detected signal representative of target information will be reduced in amplitude along with the noise components. However, as long as the amplitude of the target components exceeds the amplitude of the noise components, the attenuation of the target components will be less, thereby resulting in an increased signal-to-noise ratio. Optimization of this ratio requires the correct selection of the quiescent operating point. If the operating point is too low, the output ratio can be very small for small input ratio. If it is too high, the level of output noise becomes unacceptable. Example.
In illustrating how lowering the quiescent operating point increases signal-to-noise ratio, a square law detector diode is assumed. The square law characteristic of an ideal square law diode is:
i = k.sub.V.sup.2, (2)
as shown in FIG. 9. The quantity k is a constant. Letting V o + V t be the input target voltage, and V o + V n be the input noise voltage, the output signal-to-noise ratio, referenced to ground, can be written as: ##EQU2## Let N = V t /V n , where N>1, so that ##EQU3## To assist in the illustration, let V n = 1. Then, ##EQU4##
The output signal-to-noise ratio is graphed in FIG. 10 as a function of detector quiescent operating point, for a number of input signal-to-noise ratios. It is seen, as an example, when N = 2.0, that moving the operating point from 1.0 to 0.25 increases the output signal-to-noise ratio by a factor of 1.4, which is 3.2 dB. The improvement has been achieved at the expense of decreased system gain, for which external compensation is a simple remedy. The decrease in gain is equal to ##EQU5## which, for the numerical example, is 5 dB.
For optimum improvement in signal-to-noise ratio, the quiescent operating point should be at a voltage such that the rms noise current range corresponding to a predetermined rms noise voltage does not significantly protrude above the knee of the curve.
3. Conclusion
Proper external biasing of a video detector diode 10 results in increased signal-to-noise and target-to-clutter ratios over those which are obtained using a self-biasing arrangement. Back biasing the detector diode 10 by applied RF signals with a large energy content causes significant clutter component suppression but only slight reduction in the amplitude of strong target components in such signals. The addition of the high-pass filter network 21 following the diode detector 10 provides additional clutter reduction by suppressing low frequency components representative of clutter. | A video detector circuit for a radar system, including a detector diode having one of its electrodes connected to an input terminal for detecting an applied signal containing target information, rms noise voltage and components that are representative of clutter, and its other electrode connected to a load terminal for providing a detected signal; and a load resistance connected between the load terminal and a bias terminal; wherein a dc potential is provided at the bias terminal to forward bias the detector diode to have a quiescent operating point below the midpoint of the knee portion of its characteristic curve, thereby limiting diode rms noise current and components in the detected signal that are representative of clutter. As a result both the signal-to-noise ratio and the target-to-clutter ratio of the video detector circuit are enhanced. A filter network is connected between the load terminal and an output terminal for providing an output signal at the output terminal in which low frequency components representative of clutter in the detected signal are suppressed. | 7 |
CROSS-REFERENCE TO RELATED APPLICATIONS
None.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
Not Applicable.
BACKGROUND OF THE INVENTION
This invention generally relates to steam turbines; and more specifically, to the development of a control system for stabilizing loading on thrust bearings within the turbine to maintain thrust levels within an acceptable range of values and avoid damage to the thrust bearings.
In a rotating turbomachine, thrust is an axial force acting on the rotating parts. Thrust is caused by unequal pressures acting over unequal surface areas, and changes in momentum of the fluid (steam) circulating through the machine. The sum of all axial forces acting on the rotating components of the turbine is referred to as “net thrust”. This net thrust is transmitted to a stationary thrust bearing which, in turn, is anchored to a foundation for the turbine engine. The thrust developed by the turbine has two components. These are:
(a) Stage thrust which is thrust resulting from the pressure distribution around a stage bucket (blade), a cover, a wheel, etc. Stage thrust is usually in the direction of steam flow.
(b) Step thrust which results from variations in the diameter of the shaft to which the buckets are mounted, and the local pressure at points along the length of the turbine.
Conventional methods for controlling thrust in a steam turbine include: 1 ) using a balance piston at the high pressure (HP) section, 2 ) varying the rotor diameter in each section, 3 ) varying the number of stages comprising each section, and 4 ) establishing an appropriate configuration for each the low pressure (LP) intermediate pressure (IP), and high pressure (HP) sections of the turbine. However, all currently available methods only control thrust under “normal” operating conditions. As an engine design is completed, and its operating conditions are fixed, the net thrust of the steam turbine is specified. The methods set out above cannot now dynamically or actively adjust the steam turbine's net thrust, either under normal conditions or during fault operations.
A previous attempt at controlling thrust in a steam turbine is shown U.S. Pat. No. 4,557,664 to Tuttle, where there is disclosed use of a sealed balance piston on an overhung shaft end. The piston can be vented to an ambient pressure to balance the thrust, or vented to another control pressure to counteract any other net unbalanced forces acting across the turbine. For gas turbines, positive pressure has been used to help equalize a pressure differential across a rotor shaft. Approaches using exhaust air or gas are described in U.S. Pat. No. 3,565,543 to Mrazek and U.S. Pat. No. 4,152,092 to Swearingen.
Though such pressure equalizing features help minimize axial thrust variations during normal operations, none control net thrust for turbines operating under fault conditions. This is because the above-mentioned approaches control thrust “statically” rather than “dynamically.” To control thrust dynamically, new techniques need be developed to satisfy the requirements of the power industry.
A number of fault operating conditions have the potential of creating large thrust forces. These include:
a) Intercept valve closed condition
All reheat turbines have an intercept valve and a reheat valve connected in series between a reheater and the intermediate and low pressure sections of the steam turbine. Both valves are normally open to allow steam flow through the unit. The reheat valve acts to throttle steam flow through the reheat section following a loss of electrical load, this preventing an over speed trip of the turbine. If turbine speed continues to rise, the unit trips and the intercept valve shuts off to prevent steam flow from the reheater into a reheat turbine. An intercept valve closed condition also exists when either the intercept valve or reheat valve closes during full load operation, in response to a control system malfunction. This can result in a very large thrust load since both the intermediate and low pressure stage thrusts go to zero, while the high pressure stage thrust remains at its original level. The condition may cause a thrust reversal. That is, net thrust suddenly changes its direction from negative to positive producing a large impulse on the thrust bearing.
b) Sudden opening of control valves
When a turbine is lightly loaded, flow through the high pressure and reheat sections is relatively small. Increase in load are normally accomplished through a slow and steady opening of the control valves at a specified rate. However, if the control valves malfunction and open quickly, a high flow through the high pressure section immediately occurs. Flow through the reheat section also builds up, but with a certain lag in time due to the volume of the reheater and its associated piping. Under this condition, the thrust in the high pressure section is much higher than the reheat thrust, resulting in a large thrust load acting on the thrust bearing in the direction of high pressure flow.
c) Bottled up
When a turbine trips, the intercept valve and main stop valves of the turbine shut off at approximately the same time. All flow to the turbine stops. The high pressure and reheat sections eventually empty out into a condenser and the pressures in these sections decrease to that of the condenser. If, however, steam in the high pressure section becomes trapped between the stop valve and intercept valve, a “bottle up” occurs. Initially, the bottled up pressure equals the mean reheat pressure for normal operation. But, due to stored heat in the boiler, the pressure of the bottled up steam rises until reheat safety valves open. The opening pressure of these valves is about 1.25 times the cold reheat pressure and is the highest possible pressure in the high pressure section of the turbine.
d) Seismic event
Seismic thrust is a force acting on the thrust bearing when the turbine experiences seismic vibrations. Seismic activity is described by the maximum acceleration as a fraction of the gravity of acceleration . This seismic thrust is superimposed on the normal thrust.
To meet useful life requirements for a thrust bearing, its loading is kept within certain limits. Under normal operating conditions, thrust bearing loading must be lower than 400 psi (for a pivoted type thrust bearing) but larger than 50 psi. A setting of 50 psi avoids thrust reversal if temporary changes within the turbine upset the normal balance of forces. Second, if an intercept valve closes, the maximum allowable loading increases to 600 psi. Third, for seismic events, the maximum allowable loading is 1,800 psi.
BRIEF SUMMARY OF THE INVENTION
Briefly stated, the present invention is directed to the control of axial thrust loads in a steam turbine. This is accomplished by controlling a pressure differential across a balance piston in a high pressure section of the turbine in response to variations in net thrust. An apparatus of the invention controls net thrust in the turbine in response to changes in the operating condition of the turbine. The turbine includes a thrust bearing installed between the low and intermediate pressure sections of the turbine and the high pressure section. Load sensors installed on opposite side of the thrust bearing sense thrust loads on the bearing. A plurality of control valves act to balance pressures occurring at locations within the high pressure section. A controller is responsive to the sensors sensing a change within the turbine indicative of a significant change in net thrust to activate one or more of the control valves so to adjust the pressure within the high pressure section and maintain the net thrust within an acceptable range of thrust values.
Although primarily designed for controlling axial thrust in the high pressure section of the turbine, the invention can be implemented in other sections of the turbine as well.
The foregoing and other objects, features, and advantages of the invention as well as presently preferred embodiments thereof will become more apparent from the reading of the following description in connection with the accompanying drawings.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
In the accompanying drawings which form part of the specification:
FIG. 1 is a simplified representation of a steam turbine;
FIG. 2 illustrates a control valve arrangement of the present invention for thrust load control;
FIG. 3 is a graph illustrating control valve operation under different conditions;
FIGS. 4 a and 4 b are graphs depicting thrust ranges under normal operating conditions of a turbine and under fault conditions; and,
FIG. 5 is a flow diagram for the control system.
Corresponding reference numerals indicate corresponding parts throughout the several figures of the drawings.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The following detailed description illustrates the invention by way of example and not by way of limitation. The description clearly enables one skilled in the art to make and use the invention, describes several embodiments, adaptations, variations, alternatives, and uses of the invention, including what is presently believed to be the best mode of carrying out the invention.
In accordance with the present invention, the net thrust load of a steam turbine is controlled by controlling the pressure differential across a balance piston in a high pressure section of the turbine in response to net thrust variation. Referring to FIG. 1 , a turbine T is shown to be comprised of a high pressure section HP, an intermediate pressure section IP, and an adjacent low pressure section LP. Each section may be comprised of one or more stages. The rotating elements housed within these various stages are commonly mounted on an axial shaft or rotor S. As shown in FIG. 1 , high pressure section HP is arranged opposite to the intermediate and low pressure sections IP and LP of the turbine. This is done to balance stage thrusts. Further, a thrust bearing B is installed between sections HP and IP. The size (area) of thrust bearing B is selected to ensure that under a wide range of operating conditions (e.g., the turbine's load, operating speed, temperature, and pressure levels within the turbine, etc.), the thrust pressure will fall within a predetermined range of values.
For the turbine of FIG. 1 , step thrust is primarily developed in four packing regions: a packing N 1 at the downstream end of low pressure section LP, a packing N 2 at the upstream end of intermediate pressure section IP, and packings N 3 and N 4 at the respective upstream and downstream ends of high pressure section HP. The packings (or steam seals) are typically labyrinth type seals as is well known in the art, although other types of seals can be used. Further, as shown in FIG. 2 , the packing for a particular section of the turbine comprises a number of sealing elements such as the labyrinth seals N 3 - 1 to N 3 - 7 shown in the Figure.
The step thrusts produced in sections IP and LP are relatively small because the pressures in these sections are relatively low (from atmosphere pressure to about 50 psi in section LP, up to about 400 in section IP). The largest step thrust occurs in the packing N 4 . This is because the diameter of rotor S sharply decreases at the transition from a last stage of high pressure section HP to the packing N 4 . Step thrust at packing N 3 is subject to the next highest level of thrust due to the high pressure at this section. Because net thrust can build up to levels beyond the capability of thrust bearing B, the step thrust present at a specified location within the turbine has been used to equalize the thrust differential across rotor shaft S. This allows the thrust bearing to be of a reasonable size.
In steam turbine T, the packings N 1 -N 4 work either as pressure packings to prevent higher pressure steam from leaking out into a room (not shown) where the turbine is housed, or as a vacuum packing preventing air from leaking into the turbine. As the operating load on turbine T increases, pressure in the high and intermediate sections, HP and IP respectively, of the turbine increases. Packings at the ends of these sections (the packings N 2 -N 4 shown in FIG. 1 ) are now act as pressure packings. When the turbine is operating to cause gears to turn and a vacuum to be pulled, all of the packings (packings N 1 -N 4 ) act as vacuum packings and function to minimize steam leakage loss.
Referring to FIG. 2 , the high pressure inlet to turbine section HP is indicated L and has a general bowl shape. As leakage flow passes a component of a seal packing (e.g., packing N 3 - 1 ), a pressure differential builds up across the packing element. For example, if steam turbine T has a bowl pressure P bowl of 1930 psi at inlet L, a pressure P 1 on the downstream side of packing element N 3 - 1 may be, for example, on the order of 920 psi, or P 1 ˜920 psi. Similarly, the pressure on the downstream side of the next packing element N 3 - 2 may be, for example, 540 psi, or and P 2 ˜540 psi. Conventionally, the balance piston P in the high pressure section HP is used to control thrust of a steam turbine. Since balance pistons are known in the art, its construction and operation is not described.
Those skilled in the art will further understand that a pressure P 3 on the downstream side of packing element N 3 - 3 , a pressure P 4 on the downstream side of packing element N 3 - 5 , and a pressure P 5 on the downstream side of packing element N 3 - 6 reflect similar changes in pressure through the high pressure section of the turbine. At the outlet end of the section, at the downstream side of packing element N 3 - 7 , the pressure P atm reflects the pressure at a drain port. Utilizing the various pressures, and ambient pressure, the net thrust of turbine T is controlled within allowable regions.
A net thrust control system of the present invention is indicated generally 10 in FIG. 2 and includes a plurality of solenoid control valves CV 1 -CV 3 , and an optional control valve CV 4 . As is well known in the art, solenoid valves are control devices used to automatically control pressures at packing components in the thrust control system of turbine T. When electrically energized or de-energized, the valves allow steam to either flow or stop. Each valve has an inlet I and an outlet O.
In FIG. 2 , three solenoid valves CV 1 -CV 3 are shown connected to components of packing N 3 . A first solenoid valve CV 1 has its outlet connected to the drain portion of the turbine where the pressure is P atm . The inlet of valve CV 1 is connected to both the downstream side of balance piston P and its associated packing element N 3 - 2 where the pressure is normally P 2 , and to the outlet of control valve CV 2 . The inlet of control valve CV 2 is connected to bowl L of the high pressure section HP of the turbine where the pressure is P bowl . The third control valve CV 3 has its inlet also connected to bowl L, and its outlet is connected to the downstream side of packing element N 3 - 1 (the upstream side of balance piston P) where the pressure is P 1 . Optionally, a fourth control valve CV 4 is connected across balance piston P. It will be noted that there is a series/parallel arrangement of the control valves and that, in accordance with the invention, one or more of the control valves can be opened at one time to control net thrust of the turbine.
The control valves are normally closed and do not impact steam turbine operation. As shown in FIG. 4 b , there are four identified regions of net thrust. Regions I and II which extend from −400 psi to 0, and from 0 to +400 psi respectively represent a normal operating range for the turbine. In Region I, thrust is toward the intermediate and low pressure sections IP and LP of the turbine, while in Region II, thrust is toward high pressure section HP. Those skilled in the art will understand that the point 0 psi may be crossed over from one direction to the other during operation of turbine T, but the transition is typically a gradual transition.
Under a fault condition, however, such as when an intercept valve (not shown) is closed, the load on thrust bearing B changes sharply. Referring to FIGS. 4 a and 4 b , during the time it takes for the intercept valve to close (times t 1 to t 3 in the Figures), net thrust decreases significantly. Without thrust control system 10 , net thrust will not only keep moving from a minus psi value toward zero, but will rapidly pass through the 0 psi crossover point and change its direction from negative (i.e., toward intermediate and low pressure sections IP and LP) to positive (toward high pressure section HP). This is indicated by the dashed line in FIG. 4 b . The result is the thrust load switching from one side of thrust bearing B to the other, and producing a large force impulse on the thrust bearing. This, in turn, can cause a crash between rotating and stationary components of the turbine due to the resulting axial displacement.
In operation, control valve CV 1 of control system 10 is activated when net thrust falls to between 10-30% of its original value, but with the thrust still being within Region I of FIG. 4 b . Referring to FIG. 2 , it will be seen that with control valve CV 1 open, the P 2 at the downstream side of balance piston P will approximate the drain pressure P atm . As a result, the step thrust toward intermediate and low pressure sections IP and LP of the turbine can double or triple to balance the change in thrust.
It may be that in some situations, the generated step thrust will still not balance the thrust. In these circumstances, control valve CV 3 is also opened so to increase pressure P 1 to pressure P bowl , and produces a large pressure drop across balance piston P. By controlling the extent to control valves CV 1 and CV 3 are opened, net thrust can be precisely controlled within the allowable operation region (Region I in the above example). At this time, control valves CV 2 and CV 4 (if control valve CV 4 is used) remain closed.
If the opposite situation to that described above occurs; that is, net thrust in the direction of the intermediate and low pressure sections IP and LP becomes too large, system 10 operates to open control valve CV 2 . This has the effect of making balance piston P nonfunctional (since the pressure differential ΔP across the balance piston becomes very small). Alternatively, instead of using control valve CV 2 , if control valve CV 4 is used, opening this control valve has the same effect as opening control valve CV 2 .
In other situations, it may be desirable to open control valves CV 1 and CV 2 , which are connected in series, so to connect bowl L of high pressure section HP to the environment or drain of the turbine. Because of the series/parallel connections of the control valves, different combinations of the control valves can be opened at any one time as operating circumstances warrant to control net thrust load.
Most commercially available solenoid valves open and close substantially instantaneously. This can cause very large shock pressures within control system 10 , and potentially damage the control valves, especially at high flow velocities. To address this problem, control valves CV 1 -CV 4 include dampeners 12 by which the valves can be opened and closed in a predetermined manner during a time interval Δt. This is accomplished by inputs to the control valves from a controller 16 . In FIG. 3 , three possible paths to open and close a control valve are illustrated. These paths include linear, exponential, and logarithmic paths. While each path may have certain advantages with respect to the others, it has been found that the greatest sensitivity and effectiveness in operating a control valve, the logarithmic path is preferable. Those skilled in the art will appreciate, that certain of the control valves can be opened in accordance with one path while others are opened using a different path. Also, paths other than the three shown in FIG. 3 may be implemented without departing from the scope of the invention.
Referring again to FIGS. 4 a and 4 b , they illustrate the variation of the steam turbine net thrust as control system 10 acts in response to an intercept valve closing. For purposes of understanding operation of system 10 , it is assumed that the closing rate of an intercept valve follows the logarithmic function of ƒ(t)=ƒ(t o,lV )+b log a (t) for b<0, and the opening rate of a control valve CV follows the logarithmic function of ƒ(t)=ƒ(t o,CV )+b log a (t) for b>0. In FIG. 4 a , the intercept valve begins to close at time t 1 and reaches its fully closed position at time t 3 . As the thrust reduction is detected; for example by sensors 14 shown in FIG. 1 positioned on opposite sides of thrust bearing B and supplying inputs to controller 16 , control valve CV 1 is commanded by the system to start opening at time t 2 (using one of the paths shown in FIG. 3 ) and to complete opening by time t 4 . As shown in FIG. 4 b , during the interval from time t 1 to time t 2 , net thrust is changing, but for the entire interval from time t 1 to time t 4 , the net thrust remains is in region I. This is important, because by actively or dynamically responding to an abrupt change of conditions within turbine T, the resulting forces imparted to the turbine are constrained within acceptable limits, and the turbine does suffer any damage resulting from the change.
FIG. 5 is a flow diagram for system 10 and illustrates processing of the thrust load control. As noted, thrust load sensors 14 are installed at opposite sides of thrust bearing B to monitor and diagnose changes in thrust. During steam turbine T operation, only one side of thrust bearing B is loaded at any one time. Variation of thrust load is calculated from sensor 14 measurements as
η = F t + 1 - F t F t ,
where F t is the sensed force at a point in time and F t+1 is the sensed force at the next point in time.
When |η| is between 10-30%, control system 10 is activated. According to the sign of the thrust differential (i.e., F t+1 −F t >0 or F t+1 −F t <0), one or more of the control valves are opened to balance the thrust. Again, this dynamic response to changed conditions avoids a thrust reversal with thrust load changing from one side of thrust bearing B to the other, and provides necessary time for steam turbine T to shut down following a normal procedure.
While the invention has been described in connection with a fault condition (intercept valve closing), those skilled in the art will recognize that control system 10 of the invention can also be used with a steam turbine under normal operation of the turbine. Further, while control system 10 has been described with respect to high pressure section HP of turbine T, the control system can also be employed in either or both the intermediate and low pressure sections IP and LP of the turbine.
In view of the above, it will be seen that the several objects of the invention are achieved and other advantageous results are obtained. As various changes could be made in the above constructions without departing from the scope of the invention, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense. | Apparatus ( 10 ) controls net thrust in a steam turbine (T) in response to changes in the operating condition of the turbine. The turbine includes a thrust bearing (B) positioned between low and intermediate pressure sections (LP, IP) of the turbine and a high pressure section (HP) thereof. Sensors ( 14 ) for sense thrust loads on the thrust bearing. A number of control valve (CV 1 -CV 4 ) are used to balance pressures occurring at locations within the high pressure section of the turbine. A controller ( 16 ) is responsive to the sensors sensing a change within the turbine indicative of a significant change in net thrust to energize one or more of the control valves and to adjust the pressure within the high pressure section of the turbine so to maintain net thrust within an acceptable range of thrust values. | 5 |
BACKGROUND OF THE INVENTION
1. Field to the Invention
The present invention relates to a bobbin hanger.
2. Description of the Prior Art
The upper assemblies of conventional bobbin hangers are not very much different from each other. In a typical form of such conventional bobbin hanger, as shown in FIG. 1, inside a rotor 8 a pivot 1 is integral with a bolt 4, providing at the lower portion a bearing and swing motion mechanism, and on the intermediate portion of the clamp bolt a cap 2 is held in position by a clamp nut 13. At the upper portion, the bobbin hanger is attached to a hanger attaching rail 5 by a square bolt 6 and a fixing clamp nut 14. Finally, a protector 12 for protection against airborne short fibers, or so-called "fly" is provided over the rotor 8. Thus, the conventional article is complicated in construction, having a large number of parts, and requires much time and labor in mounting and dismounting operation and yet not much of the expected effect can be obtained. Fly tends to enter the bobbin hanger and since the pivot is integrally connected to the hanger attaching rail, the formation of rust and dew on the pivot due to heat conduction detracts from the performance of the bobbin hanger and causes many troubles. In addition, 15 designates a ball for rolling movement and 7 designates a washer.
SUMMARY OF THE INVENTION
The present invention relates to a bobbin hanger for use primarily with textile machines and includes an assembly wherein in order to threadedly attach the upper and lower assemblies of a bobbin hanger to a bobbin hanger attaching rail for suspension or transport of bobbins by using a rational arrangement meeting the functional requirements of bobbin hangers, a clamp bolt and a bearing pivot (hereinafter referred to simply as pivot) are gripped in a self-centering universal joint fashion. The assembly comprises a pivot housing split usually into two sections, which are adapted to be put together by being inerted into a cylindrical long aperture formed in a cap. Thus, basically the invention provides a vertical suspension device whereby the bobbin hanger is completely isolated from the bobbin hanger attaching rail in terms of operation, air current convection and heat conduction. Further, associated with said device, as necessary adjuncts the invention provides a lower suspension structure and a seal structure for prevention of entry of fly and dust.
FEATURES OF THE INVENTION
The first feature of the present invention is that in order to eliminate the various disadvantages described above, there is provided a bisected pivot housing whereby the pivot and the lower assembly are completely isolated from the bobbin hanger attaching rail in terms of operation, convection and heat conduction, as described above, said pivot housing, as shown in FIGS. 2 and 3, being provided with a lower recess in which, when the pivot housing halves are put together, the head of the pivot is held in a self-centering universal joint fashion, and with an upper recess adapted to receive the head of a clamp bolt to be threadedly secured to the hanger attacing body. Thus, said lower recess receives the pivot in a self-centering universal joint fashion while the upper recess fixedly receives the head of the clamp bolt, and the pivot housing itself is fitted in a cylindrical long aperture formed inside a cap when the housing halves are put together.
This arranngement is advantageous in that the hanger upper assembly can be easily and securely threadedly attached to the hanger attaching rail, that fixing and detachment are easy and that the number of parts is minimum.
The second feature of the invention is the provision of a protector for prevention of entry of fly and dust into the rotatable bearing structure when the upper and lower assemblies in the vertical suspension device of the present invention are in self-centering universal joint condition.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a bobbin hanger upper assembly according to the prior art;
FIG. 2 is a sectional view of an embodiment of the hanger upper assembly of the present invention;
FIG. 3 is an exploded perspective view of the upper assembly of the present invention;
FIGS. 4A-4D are partial views of various dust-proof devices according to the present invention;
FIG. 5 is an exploded view of the upper assembly of the present invention; and
FIG. 6 is a sectional view of a typical vertical suspension device for bobbins, shown in its entirety, according to the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 2 shows an embodiment of the present invention, illustrating the upper assembly of a hanger threadedly secured to a hanger attaching body with the parts shown in partial section. A bisected pivot housing 3 is provided with a lower recess 9 for receiving the head of a pivot 1 in a self-centering universal joint fashion, and an upper recess 10 for similarly receiving the head 16 of a clamp bolt 4 which is threadedly secured to a hanger attaching body 5 with a washer and a loosening-preventive specially shaped polygon head nut 6. The pivot housing 3 itself is fitted in a cylindrical long aperture 11 formed inside a cap 2 whereby it is integrally embraced and fixed in position.
FIG. 3 is a perspective view showing the pivot 1, the internal structures of the bisected pivot housing 3, 3' and cap 2, and the bolt 4 and besides them it also shows the relation thereto of a rotor bearing member for rotatably suspending the lower assembly. As shown in FIG. 3, the bisected housing 3, 3' is internally provided with a lower recess 9 for receiving the head of the pivot 1 in a self-centering universal joint fashion and an upper recess 10 for receiving the head 16 of the clamp bolt 4.
Further, the cap 2 is provided with a cylindrical long aperture 11 in which the pivot housing 3, 3' is fixedly fitted when the halves are put together.
In FIG. 3, the cap 2 is not a bisected but an integral one and it is shown split in order to illustrate the construction of the inner cylindrical long aperture. Designated at 41, 41' is a rotor bearing member adapted to be fitted over a bearing hemispherical body formed on the lower portion of the pivot housing 3, 3'.
The rotor bearing member 41, 41', like said pivot housing, is of the split type which is characteristic of the present invention, designed to be strongly united by a washer 40 for jointing the leg portion of the split bearing member 41, 41' and by a rotor housing 42 adapted to integrally embrace the rotor bearing member 41, 41', thereby constituting a vertical suspension device according to the present invention.
In the embodiment of the invention, the rotor bearing member 41, 41' is functionally the most important part. That is, besides the bearing function of self-centerably and rotatably suspending the lower assembly, the front end of the leg is provided with a clutch functional portion which performs its own peculiar action and the upper disc surface is opposed to the lower end surface of the pivot housing projecting at the center inner portion of the top cap, with a particular clearance therebetween, so that in bobbin hanger operation, it performs also the functions of a stop and a shock absorber or damper. Further, the central position of a filter F of dust-proof construction to be later described is held by the circular edge of the tray-shaped circular plate which also helps the filter F to provide a sufficient dust-proof effect.
Further, the rotor housing 42 for integrally embracing the rotor bearing member 41, 41' to suspend the lower assembly from the pivot P serves the following important role. Thus, it unites the split rotor bering member 41, 41' in such a manner as to embrace the latter with pivot 1 inserted in the inner recess; after the washer 40 is tightly fitted over the leg from the front end thereof to unitarily constrain the same, this unitary assembly is completely received in the cylinder of the rotor housing 42 in a tightly fitted condition to serve as a core to tighten the upper portion of the rotor housing 42, thus providing a strong unitary lower structure.
The second feature of the present invention is the provision of a dust-proof structure for prevention of entry of fly and dust into the rotary bearing structure in an arrangement wherein the upper and lower assemblies in the vertical suspension device according to the present invention are joined together in a self-centering universal joint fashion.
In spinning mills, measures against fly and dust are unavoidable important problems. It has been ascertained from of old that most of the causes of troubles to the gearing in the upper structure of the conventional bobbin hanger as shown in FIG. 1 are attributable to entry of fly in addition to rusting and dewing phenomena due to variations in temperature and humidity. As a conclusion drawn from the long-established actual results it has been considered that there is no other measure for protection against dust and fly then resorting to absolute sealing. As a bobbin hanger construction, however, in order to suspend the upper and lower assemblies in a self-centering rotatable manner, it is impossible to employ such absolute sealing system.
Although the conventional bobbin hanger has a kind of measure for protection against fly incorporated therein as shown in FIG. 1, the actual results have proved that it can hardly perform its role. That is, in terms of convection, head conduction and temperature and humidity, the measure for protection against dust and fly leaves the parts almost exposed, and the measure for protection of the rotary bearing against dust using a cover 12 to reduce the clearance as seen in FIG. 1 often produces adverse effects with respect to entry of fly.
Moreover, a bobbin hanger of the FIG. 1 construction having a lower actuating device of the piston type inside the rotor 8 entails more difficult problems connected with protection against fly.
As a measure for protection against fly in the present invention, first, fly and dust are conveyed by air currents. That is, the main bearing portion is isolated from ambient air and air current region in the hanger upper structure as much as design permits.
Secondly, the principle is to isolate the boundary clearance between the fixed parts and the slowly rotating parts from the outer atmosphere by a stationary air curtain layer enclosed in said clearance. As contrasted with this protection against entry of fly according to the second principle, the forcible elimination of such clearance would produce adverse effects on the protection of the rotating parts against entry of fly, as described above.
In the present invention, it has been found that the technique of combining wide, narrow and bent portions to connect the clearances successively effectively in series is more effective for protection against fly floating in the air.
Thus, the preventive system according to the present invention combines the above described two principles in a rational manner. As shown in FIG. 2, ambient air goes in and out of the space f as indicated by arrows as the rotor bearing member moves up and down as a result of the suspension action of the rotor bearing member.
Therefore, as shown in FIG. 2, the pivot 1 is installed in a sealed chamber isolated from the moving parts and communication with ambient air is through spaces a, b, c, d and e. The inlet a contacts ambient air over a relatively small area and the distance to the pivot is relatively long. Moreover, no current is produced in the wide, narrow and bent portions and there is formed a labyrinth effective to block the entry of fly.
Although some amount of alternating air current will be produced by the action of the rotor bearing member, owing to the very slow speed of the rotor bearing member and the reservoir effect of the intermediate wide space c, only a faint alternating current is produced in the inlet a. Long-term tests in spinning mills have proved that such various measures against entry of fly are effective particularly with respect to fine dust. However, it is necessary to exercise caution against the fly in a spinning mill tending to enter any clearance particulary defined between rotating parts as in an arrangement of bobbin hangers and in an area where there are various air currents including turbulent flow. There have been few cases where measures against fly under such unfavorable conditions are successful. Particularly where the fibers in the fly are long, the situation is aggravated. In the case of a bobbin hanger, if one end of a good fiber touches the bearing for one causes or another, it is instantly caught in the bearing. Fly tests on bobbin hangers have proved that even the above described means is still insufficient to avoid accidental occurrence of this phenomenon.
In view of the above, the present invention has completed a dust-proof device having a unique effect combined with the results of the later researches.
The principle is shown in FIG. 4, wherein the top cap inner aperture circular outer wall periphery 52 occupying a suitable outer peripheral length erected in a fixed condition inside a dust-proof chamber formed inside said top cap, and the rotary disc surface construction of a top clutch 55 forming the upper horizontal surface of the rotor R are utilized and a dust-proof float F (hereinafter referred to as filter) forming a conical partition wall is loosely fitted. This is a method in which the entry of long fibers having the danger of twining around the pivot P is blocked by this partition wall.
Generally, relatively long fibers in the fly floating on a rotating part has the characteristic of readily twining around a thin core. Therefore, they have a tendency to twine around a core of small diameter, such as the pivot P, extremely readily. In this case, if the circumference is longer than the staple length, twining, generally, will not take place. With this characteristic of fly taken into account, if all the circumferences of the related parts constituting a seal structure are suitably dimensioned, it is possible to form a sure seal structure against fly.
The construction of a suspension device according to the present invention is given an arrangement most suitable for application of this seal system, and it is characterized in that the related conditions are all met. Therefore, in an arrangement of the two combined, it is possible to provide an almost perfect dust-proof seal.
It is theoretically and experimentally proved that the dust-proof seal of the present invention will develop a superior sealing effect with respect not only to the usual short fiber fly as well as dust but also to a fly containing long fibers.
Moreover, this dust-proof seal is characterized in that it has almost no influence on the rotation resistance torque of a rotating part R, which is considered to be important. Thus, as a result of the fact that a superior seal construction for the bearings of bobbin hangers, the provision of which has been a long pending problem, has been accomplished, there is provided an arrangement which assures the performance and durability of a bobbin hanger for a prolonged period of time, resulting in remarkably improving its reliability and achieving a maintenance-free condition.
Features of the present invention will now be described with reference to embodiments thereof.
First of all, it is characterized in that the configurational design of the various elements constituting the internal space construction of the top cap C which is the main part of the suspension device is provided with precalculated conditions most effective for the dust-proof seal. A clearance 53 adjacent the lower edge of the cap which is the only path allowing the passage of fly has a specially selected sectional shape for prevention of entry of long fibers. At an important position in this space construction having the following combination of conditions, a conical filter F is installed as shown in such a manner as to isolate a reception chamber M for the pivot P from ambient air. That is, the upper portion of the conical filter F is located adjacent the upper corner in such a manner as to be positioned close to the internal cylindrical outer periphery 52 of the fixed upper assembly while the bottom edge of the conical filter F is closely contacted with the upper horizontal surface of the rotor R, so that the filter is positioned in an almost playing condition near the corner defined by a circular ring-like lateral wall erected around the circumference of said horizontal surface carrying the total weight of the filter F.
As a result, during the rotation of the rotor R, the filter F follows the movement of the rotor R while being restricted by the inner surface of the circular ring-like edge and continues rotating along with the rotor R while maintaining the central position which the filter F should assume. The well-prepared environmental conditions described above all act favorably, and even if an obstacle to rotation should be caused by fly taking various attitudes, the filter F itself skillfully and rationally adapts itself to this situation so as to retain the conditions for stability without interfering with the rotation of the rotor R.
The filter F is further characterized in that its blocking surface is always located at the greatest possible distance from the main position where there is the danger of causing twining around the pivot P and that the outer diameters of the upper and lower end surfaces of the filter and associated parts are such that their circumferences are above the limit (experimentally, 38 mm) where twining of fibers does not take place.
In this embodiment, the circumference of the surface 52 to which the upper edge of the filter F is disposed close is a little over 40 mm and the circumference of the lower edge thereof amounts to 75 mm.
Tests have proved that this fact, combined with the proper clearance between the upper assembly and the lower assembly forming the rotary part, makes it possible to form a fly- and dust-proof seal construction which is satisfactory for use in connection with the processing of long fibers such as synthetic fibers and wool as well as cotton.
The shape of the filter F, when considered from the purport and principles described above, is not restricted to simple conical shapes shown in FIGS. 4A, B, C and D and many other shapes can be found, each developing its own characteristics.
Further, various methods of production may also be contemplated. Metal plate shaping, molding and coiling are good examples thereof. Particularly, when a coiled filter shown in FIG. 4D is put into practical use, it has been proved that such filter has a decidedly superior effect as compared with flat simple cylindrical or conical forms made of metal plate or plastics. The effect factor which accounts for this reason is that the surface area which blocks fly can be several times larger than a flat type and that the surface unevenness facilitates the adhesion of fly to the surface in such a manner that the adhering fly collects as scattered over the entire surface of the filter. This phenomenon has the unique effect of gradually promoting the filter effect with the lapse of time. Particularly, it most effectively prevents long fibers from entering the filter. Further, the presence of some clearances is useful for arresting fly on the uneven surface. Therefore, there develops the action of further promoting the filter effect due to the deposition of fly concerning said coiled filter. That is, in the case where the filter surface is flat and has no clearance, no such effect is obtained and fly falls downward to form masses or slips in from below. If the coiled filter is conical, a superior effect can be expected. This effect can be explained by the fact that it is natural that spacing the rotor R as far as possible away from the pivot which is the object around which fly twines is effective for prevention of such twining. Another merit is that the inclined blocking surface has a stronger tendency than a vertical blocking surface to allow the layer of fly deposited thereon to become stabilized in that position. Further, if a fine wire is used to form a coil, it is possible to produce a filter which will flexibly accommodate itself to rotation. It is free to plan to produce filters which are best suited for individual fiber characteristics in accordance with the purport of the present invention. At any rate, the effective use of the present invention makes is possible to realize the desire for providing a seal construction which eliminates the trouble casued by twining of fly which has heretofore been considered unavoidable.
Thus, there is no possibility of entry of fly and dust.
The third feature of the present invention is that the outer side of the cap 2 depends downwardly over a long distance with the inner peripheral surface of its lower edge opposed to and disposed adjacent the outer periphery of the lower portion of the rotor housing 42 with a predetermined relatively narrow space therebetween, so that the swing motion of the rotor housing 42 constructed to swing with the pivot 2 as a double joint core is confined within the given limits naturally determined by the inner periphery of the lower edge of the cap.
Further, when the suspended body is swung by external forces, its amplitude is restricted and the initial attenuation is accelerated. This is useful for protecting the function of the important bearing and preventing aggravation in quality due to the swing of bobbins of roving and is an indispensable condition for retention of the bobbin hanger function.
The features of the present invention may be summarized as follows.
As the upper assembly of the vertical suspension device of the self-centering universal joint type:
a. In pursuit of rationality matching with the times, any loss in design is avoided to assure ruggedness, reliability, safety, convenience and neat appearance. The reliability of the function is very great, thus remakably improving yarn quality and operational stability.
b. The pivot housing and cap are moldings, and since the pivot housing is split, though complicated in design it is very easy to manufacture and assemble and the cost is low.
c. The parts are small in number and easy to manufacture with no waste of material. The molds are easy to design and produce with high precision.
d. The mounting and dismounting operation with respect to the hanger attaching body can be effected easily, quickly and securely without requiring a great amount of skill.
e. Standardization is simple and easy.
f. The self-centering universal joint type bearing pivot and the creel attachment bolt are isolated by the housing assembly in terms of operation, air convection and heat conduction. In the textile machine bobbin hanger bearing structure embodying the present invention, the protection of the bearing pivot is perfect and rational, assuring retention of the normal function with high reliability.
While there have been described herein what are at present considered preferred embodiments of the several features of the invention, it will be obvious to those skilled in the art that modifications and changes may be made without departing from the essence of the invention.
It is therefore to be understood that the exemplary embodiments thereof are illustrative and not restrictive of the invention, the scope of which is defined in the appended claims and that all modifications that come within the meaning and range of equivalency of the claims are intended to be included therein. | There is disclosed a bobbin hanger comprising an upper assembly serving for attachment and aligning suspension, an intermediate assembly serving for constrained rotation and alignment, and a lower assembly serving for removable mounting and aligning suspension of a bobbin. Below the upper assembly, the intermediate assembly is suspended through a pivot having enlarged head portions at both ends thereof, and a dust-proof filter is incorporated between the upper and intermediate assemblies for prevention of entry of fly and dust. | 3 |
BACKGROUND OF THE INVENTION
The U.S. Government has rights in this invention purusant to Contract Number DE-AC02-76CH00016, between the U.S. Department of Energy and Associated Universities, Inc.
This invention relates to a fluid spraying machine and particularly to a portable machine for spraying quick setting resins onto a roadway.
During recent years two component resin compositions have been developed for industrial and commercial uses. These resins, which consist of a resin material and a hardener or curing agent, are maintained as separate viscous liquids until they are mixed together, at which time a thermal reaction takes place resulting in the liquid becoming a solid which has a combination of properties extremely useful in a wide variety of applications.
One application for these resins is as an overlay or coating for road surfaces. If a resin coating is applied to the road surface and sand or other aggregate spread over the surface prior to its setting, a tough, coarse and relatively impenetrable weather resistant surface is obtained, thereby protecting and extending the life of the road surface.
In order to apply the resin, it is necessary to have a machine capable of maintaining the two components of the resin at suitable temperatures prior to mixing, and then effectively mixing the resin components and applying them to the roadway at a controlled rate. Due to the quick setting nature of the resin when it has been mixed with the curing agent or hardener, it is essential that provisions be made for effectively and simply cleaning the machine once spraying has stopped to prevent hardening of the resin mixture in the machine. The machine should be simple to operate and failsafe so that in the event of a loss of power or failure of any components of the machine the operator can discharge all of the activated resin which has been mixed and clean the machine to ensure that the mixed resin does not harden in the mixing chamber or spray nozzles of the machine. In addition, the machine should have interlocks which prevent improper operation of the machine such as the introduction of solvent during application of the resin to the roadway.
BRIEF DESCRIPTION OF THE INVENTION
The present invention provides a pneumatically controlled machine for spraying quick setting resins onto a roadway and includes an ice water cooling system to control the temperature of the resin and curing agent, as well as a circulating system for keeping the resin and the curing agent "fresh" prior to their mixing. In addition, the machine provides a flushing and cleaning system which utilizes a minimum of solvent and in which pressurized air is used to purge the system of excess mixed resin prior to cleaning with a solvent and in which pressurized air is used to remove excess solvent after cleaning. The machine is failsafe so that in the event of a failure of the pumps or electrical system the available compressed air can be used to purge the system and flush it with solvent to remove any mixed resin, thereby preventing the resin from hardening in the mixing chamber and spraying mechanism.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a plan view of a mobile apparatus showing a preferred embodiment of the present invention.
FIG. 2 is a schematic view showing the control system for the apparatus of FIG. 1.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to FIG. 1, there is shown a truck 10 which includes a chassis 12 on which a spraying apparatus is mounted. A gasoline driven electric generator set 14 provides electricity for the system, as well as sufficient electricity to operate portable tools and auxiliary lighting. The major components of the resin spray system include a storage tank 16 for the resin, a storage tank 18 for the curing agent, vane pumps 20 and 22 for the resin and the curing agent respectively, and a gasoline driven engine 24 for driving the pumps through an integral reduction gear and mechanical clutch and drive chain 26. The outlet lines 28 and 30 of the pumps 20 and 22 are connected to air actuated ball valves 32 and 34 respectively, which act as diverter valves, as explained below. The outlet of the storage tank 16 is connected to the inlet of the pump 20 via line 36, while a return line 38 connects one outlet of the valve 32 to the storage tank 16. Similarly, the outlet of the curing agent storage tank 18 is connected to the pump via line 40, while the line 42 provides a return to the storage tank from the pump 22. A second pair of three-way air actuated ball valves 46 and 48 are connected to the discharge lines 50 and 52 of the diverter valves 32 and 34 respectively. The outlets of the valves 46 and 48 are connected to a static mixing chamber 54 via the lines 56 and 58, so valves 46 and 48 are designated mixing chamber valves herein. A horizontal header or spray manifold 60 is connected to the mixer 54 via the line 62. The spray manifold, which includes a series of equally spaced spray nozzles along its underside, can be raised or lowered so that the clearance between the spray manifold and the roadway can be adjusted. In addition, the spray manifold may be angled with respect to the road direction to compensate for different road widths.
Referring now to FIG. 2, heat exchange means for cooling the resin components are supplied by having ice water, or other cooling fluid, circulated through the water jackets of the resin pump 20 and the curing agent pump 22 from a storage tank 70 via an electric pump 72 and lines 74, 76, 78, and 80. The electric pump is thermostatically controlled via a thermostat 81 to maintain the temperature of the resin and curing agent within a predetermined range.
A solvent storage tank 83 is connected to inlets of the valves 46 and 48 via line 82, a ball valve 84, and line 86.
All functions are controlled by a pneumatic air system, which includes an electrically driven air compressor and storage tank 100, to provide a source of compressed air, a shut-off valve 102, and an air pressure regulator 104. All of the pneumatic control lines are one-quarter inch tubing, except for the the one-half inch line 106, which directly connects the compressor outlet to the large bore control valve 108, the outlet of which is connected to the pipe 86 via a check valve 110. The valves 32 and 34 are coupled to a double shafted pneumatic valve actuator 112, so that they always operate in unison. Similarly, a double shafted pneumatic valve actuator 114 controls the valves 46 and 48 so that they also act in unison. The actuators 112 and 114 are connected to a two-position four-way manual pneumatic-flow control valve 115 via line 116, which branches to form lines 118 and 119, connected to one side of the actuators 112 and 114 respectively, and a line 120 which branches to form line 122 and line 124 connected to the other sides of the actuators 112 and 114 respectively. A quick exhaust valve 125 is located in line 118 and a similar quick exhaust valve 127 is located in line 124.
The control valve 115 is mounted on a control panel 130 shown in FIG. 1 along with the push button spring-return four-way control valve 132, and push button spring-return three-way valve 134. The inlet of valve 132 is connected to the air supply via line 140, line 120, and then valve 115. A line 142 connects valve 132 to the solvent storage vessel 83 via a quick exhaust valve 144, and line 146. The valve 132 is also connected to the open side of the ball valve control actuator 150 via a line 152. The close side of the ball valve actuator is connected to solvent supply actuator valve 132 via line 154, shuttle valve 156, line 158, and line 160. The opposite side of the shuttle valve 156 is connected to line 119. The air purge release valve 108 is connected to the air supply via line 170, three-way spring-return push button air supply actuator valve 134, line 160, valve 132, and valve 115.
OPERATION OF THE SYSTEM
There are four modes of operation of the system, all controlled by the three valves (115, 132 and 134) on the control panel 130. Prior to the mixing and spraying operation, the resin flow control valve 115 is in the "out" position, in which compressed air from the regulator 104 passes through the valve via lines 113, 120, and to the resin control valve actuators 112 and 114 via lines 122 and 124. In this mode of operation, the diverter valve 32 connects the outlet of the pump 20 to the return line 38 of the storage tank 16, so that the resin is continuously circulated to maintain its "freshness". Similarly, diverter valve 34 directs the outlet of the pump 22 to the tank 18 via pipe 42, thereby circulating the curing agent for the same purpose. The pump 72, which may be thermostatically controlled, circulates ice water or other cooling fluid through the water jackets of the pumps 20 and 22 from a supply tank 70, thereby maintaining the temperature of the resin and curing agent at a level sufficient to ensure curing in the desired time after mixing. The other sides of the actuators 112 and 114 are connected to the flow control valve 115 via lines 116, 118, and 119. A quick exhaust valve 125 in line 118 ensures that the diverter valves 32 and 34 will divert the resin and hardening agent flow to the recirculation mode prior to the closing of the mixing chamber valves 46 and 48.
When the operator desires to spray resin on the road surface, the valve 115 is pushed "in", thereby reversing the pressures on the actuators 112 and 114. The quick exhaust valve 127 in line 124 ensures that the mixing chamber valves 46 and 48 will move to the open air supply position in which resin flows from the line 50 and line 56 to the mixer 54 and a curing agent flows from the line 52 and 58 to the mixer 54 prior to the opening of valves 32 and 34, thereby preventing a blocking of the pump discharge. Before the shifting of the resin supplying, mixing chamber valves 46 and 48, a branch line 184 and the shuttle valve 156 operate to connect the air supply to the closing side of the ball valve actuator 150 to close the ball valve 84 and prevent the flow to or from the solvent tank. As soon as the valve 115 is moved to the "in" position in which resin and hardener flow to the mixer 54, valves 132 and 134 lose their air supply and are deactivated so as to prevent the accidental injection of solvent or air into the resin mixture while spraying is in progress. The resin and hardening agent are mixed in the static mixer 54 and discharged through the spray nozzles of the spray manifold 60.
When spraying is completed, or when it is necessary to interrupt the spray operation for any reason, valve 115 is moved to the recirculate or "out" position described above, thereby closing off the flow of resin and hardener to the mixer and diverting the pump outputs to circulate the resin and hardener as described above. Air pressure will now be supplied to the solvent supply actuator valve 132 and to the air supply actuator valve 134 via lines 120, 140 and 160, while a branch line 158 will shift the shuttle valve 156 and will maintain the ball valve 84 in the closed position.
As soon as the spraying is completed, the operator will push the air supply actuator valve 134, thereby opening a large bore air purge release valve 108 to allow compressed air from the compressor 100 to flow through the check valve 110 via line 106, and through the opened valves 46 and 48 to force mixed resin out of the mixer 54 and spray manifold 60. After a few seconds most of the mixed resin will have been forced out of the mixer and spray head and valve 134 is released and solvent supply actuator valve 132 is depressed to inject a resin solvent to the mixer and spray head. With valve 132 depressed, the air supply is admitted to the solvent tank 83 via lines 142 and 146 to pressurize the tank. At the same time, a branch line 152 applies pressure to open the ball valve actuator 150 to release ball valve 84. When the pressure in tank 83 is sufficient, the ball valve 84 will open and the solvent will be forced through the static mixer into the spray manifold and out through the spray nozzles, thereby cleaning any resin residue. The check valve 110 prevents the flow of solvent back into the air supply system. The activation of valve 132 diverts the air supply away from valve 134, thereby deactivating it and preventing the accidental release of purge air while the system is being flushed with solvent. When the solvent flush is completed, the valve 132 is released, thereby closing the ball valve 84, releasing the pressure in the solvent tank 83 (which is vented through quick exhaust valve 144), and reactivating the air purge valve 134. A second air purge will eliminate any residue of solvent or resin remaining in the mixer and spray manifold, whereupon the cycle is complete and the machine is ready for re-use. | A portable machine for spraying two component resins onto a roadway, the machine having a pneumatic control system, including apparatus for purging the machine of mixed resin with air and then removing remaining resin with solvent. Interlocks prevent contamination of solvent and resin, and mixed resin can be purged in the event of a power failure. | 4 |
STATEMENT OF GOVERNMENT INTEREST
The present invention was made with Government assistance under DARPRA/US Air Force Grant No. F33615-01-C-2172. The Government has certain rights in this invention.
FIELD OF THE INVENTION
The present invention is related to solids containing nanotubes that are operative to communicate gas and/or electrical charge. The present invention is also directed to catalyst inks and layers, as well as membrane electrode assemblies and electrochemical cells. The present invention also concerns fuel cells.
BACKGROUND OF THE INVENTION
In many applications it is desirable for gas and/or electrical charge to diffuse or otherwise pass into or through a solid layer. Often, however, the solid material may not support useful rates of diffusion or other mechanisms for passing gas and/or charge. By way of example, catalyst particles dispersed in a so-called catalyst layer in an electrochemical cell or fuel cell provide a catalyzing medium spread over an area. In order for the catalyst particles in the layer to be active, they will desirably have relatively easy access to gas and be able to conduct electrical charge. The layer may also be required to conduct protons. Proton conducting materials, however, often do not provide good support for gas and/or charge diffusion and conduction.
Catalyst layers are of particular utility when used with electrochemical cells employing a membrane and electrode assembly, with an example being proton exchange membrane (PEM) fuel cells. These cells may include a membrane electrode assembly (MEA) consisting of a proton exchange or solid polymer electrolyte membrane coated on one or both of its operative surfaces with a catalyst layer. Fuel and air are converted to electricity on the MEA, with the catalyst layer providing for higher conversion rates. The active catalyst typically comprises precious metal particles, and most commonly one or more of Pt, Pd, or Ir; or Pt or Pd alloyed with one or more of Pd, Ru, Mo, Ni, Fe, Co, Mn.
Because of their expense, it is desirable to minimize the amount of catalyst particles required while maintaining high levels of cell efficiency. Accordingly, it is desirable for high proportions of the catalyst particles to be active. Also, providing thin catalyst layers may be useful to minimize the catalyst particle cost. Catalyst inks that include catalyst particles suspended in a solvent are useful for providing a thin catalyst layer. For example, it is known to spread a catalyst ink on a proton exchange membrane and then hot press the resultant structure to remove the solvent and fix the catalyst particles near the surface of the membrane. Such a method is described in detail, for example, in U.S. Pat. No. 5,234,277 to Wilson et al., and “A NAFION-Bound Platinized Carbon Electrode For Oxygen Reduction In Solid Polymer Electrolyte Cells,” A. K. Shukla et al., J. Appl. Electrochem., 19 pp. 383–386 (1989). These methods and resultant catalyst layers, however, have problems associated with them. For example, hot pressing can result in damage or destruction of the membrane, and can result in poor mass transfer and proton conductivity within the catalyst layer. These problems cause reduced fuel cell efficiency and current output from the cell.
A solution to some of the problems of these prior art inks and layers was proposed in U.S. Pat. No. 5,415,888 to Bane jee et al. Generally, the '888 patent teaches the addition of proton-conducting polymers, such as NAFION (NAFION is a registered trademark of the DuPont Chemical Corporations, Wilmington, Del.), to a catalyst ink. Inclusion of the proton-conducting polymer reduced the need for hot pressing and its related disadvantages. In practice, the catalyst ink is applied to the proton exchange membrane and the solvent is removed, leaving catalyst particles embedded in a thin layer of the cast proton-conducting polymer. In addition to acting as an electrolyte to provide a path for proton conduction away from the catalyst, the solid proton-conducting polymer also fixedly holds the catalyst particles in position.
The teachings of the '888 patent leave several problems unresolved. For example, a portion of the active catalyst is often buried in the proton-conducting polymer layer, which generally does not support good rates of gas diffusion or electron conduction. In a buried state the catalyst particle is thus essentially inactive and wasted because it is not easily accessible to reactants (i.e. fuel or air/oxygen) or to the current collector. Wasted catalyst keeps the relative cost of these methods and layers high and lowers their efficiency. Also, the cast form of the proton-conducting polymer that results when the catalyst ink dries typically does not have satisfactorily, high proton conductivity. These and other problems are discussed in “Effects Of NAFION Impregnation On Performances Of PEMFC Electrodes,” Lee et al., Electrochimica Acta 43(24):3693–3701, 1998.
A more recently proposed solution is presented in U.S. Pat. No. 6,309,722 to Zuber et al. The '722 patent teaches adding insoluble components to the inks to induce porosity in the conducting polymer layer. The porosity partially overcomes problems associated with the catalyst being isolated from the reactants. However, the porosity does not overcome the problem of the catalyst being electrically isolated from the current collector or the problem of the limited proton conductivity of the cast proton-conducting polymer. In addition, achieving porosity adds time and cost to the preparation of the catalyst inks and layers.
Some prior art fuel cell applications seek a high density catalyst loading in order to achieve small fuel cell size. For example, in mini and microelectronics applications small fuel cells are desirable. For these applications, the prior art has had limited success in achieving suitably high loadings.
These and other problems in the art remain unresolved.
SUMMARY OF THE INVENTION
In an exemplary solid of the invention, carbon nanotubes are distributed in a solid material, with at least 1% by weight of the nanotubes having unobstructed inner passages and thereby operative to communicate gas within the solid. More preferably, at least about 10% by weight, and most preferably at least about 50%, of the nanotubes have unobstructed inner passages.
In other exemplary embodiments of the invention, catalyst inks and layers of the invention include carbon nanotubes to communicate gas and/or electrical charge. A catalyst ink of the invention includes a solvent with carbon nanotubes and catalyst particles dispersed in the solvent. At least about 1% by weight of the catalyst particles, are independent from the carbon nanotubes. More preferably, at least about 5% by weight, and most preferably at least about 75% by weight of the catalyst particles are independent of the carbon nanotubes.
An additional exemplary catalyst ink of the invention includes a solvent with carbon nanotubes and catalyst particles dispersed in the solvent. At least about 1% by weight of the carbon nanotubes have unobstructed inner passages. More preferably, at least about 10% by weight, and most preferably at least about 50% by weight of the nanotubes have un-obstructed inner passages.
Still another exemplary embodiment of the invention is directed to a catalyst layer. The layer includes a proton-conducting layer with catalyst particles and carbon nanotubes fixedly held therein. The carbon nanotubes are operative to communicate gas and electrons within the layer. The catalyst particles may have a diameter that is larger than the diameter of an inner passage of the carbon nanotubes.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a flowchart illustrating an exemplary method of the invention;
FIG. 2 is a cross section of a portion of an exemplary catalyst layer of the invention;
FIG. 3 is a cross section of an exemplary membrane electrode assembly of the invention;
FIG. 4 is a schematic, partly in cross section, of an exemplary fuel cell of the invention;
FIG. 5 illustrates experimental results in graphical form; and,
FIG. 6 illustrates additional experimental results in graphical form.
DETAILED DESCRIPTION
An embodiment of the present invention is directed to solids having nanotubes distributed therein for communicating gas. Some exemplary embodiments of the present invention are directed to catalyst inks, as well as to methods for making catalyst inks. Other embodiments of the invention are directed to catalyst layers, to membrane electrode assemblies, and to electrochemical cells. It will be appreciated when considering discussion and description of any particular embodiment of the invention that such description and discussion may be useful in considering other invention embodiments. For example, it will be appreciated that discussion of a method for making a catalyst ink of the invention will be useful in considering a catalyst ink of the invention, and that discussion of a catalyst ink of the invention will be useful in considering a catalyst layer of the invention that may be formed through application of the ink. All of the various embodiments of the invention have in common that they include carbon nanotubes. It has been discovered that nanotubes provide valuable advantages in their ability to communicate gas and electrical charge in the invention embodiments.
The present invention provides many advantages and solves many problems of the prior art. For example, it has been discovered that inclusion of carbon nanotubes in catalyst inks and catalyst layers of the invention substantially improves the efficiency of the inks and layers over the prior art. It is believed that carbon nanotubes provided in catalyst inks and layers of the present invention generally act as paths for electron conduction and for efficient gas communication. As a result, a high proportion, and preferably substantially all of the catalyst particles in inks and catalyst layers of the present invention are active. Catalyst inks and layers of the invention can therefore be formed using less catalyst than in some inks and layers of the prior art without a corresponding loss in efficiency.
Those knowledgeable in the art will appreciate that a “carbon nanotube” is a structure of carbon atoms having a generally cylindrical shape and an inner passage. That is, a carbon nanotube is a structure of carbon atoms arranged in a general tube shape. Carbon nanotubes are useful for, among other things, communicating gas through their inner passages, and for communicating electrons along their walls. A variety of particular carbon nanotubes are possible, with single and multiple wall tubes being two examples. A wide range of lengths, diameters, and weights of carbon nanotubes are possible. Many references are available to provide further detail regarding carbon nanotubes, including “Carbon nanotubes—the route toward applications,” Baughman R H. Zakhidov A A. de Heer W A. Science. 297,787–792(2002), incorporated herein by reference.
Turning now to the drawings, FIG. 1 is a flowchart illustrating an exemplary method for making a catalyst ink of the invention. In a first step, catalyst particles are dispersed in a water solvent (block 10 ). A proton conducting polymer solution containing a proton-conducting polymer dissolved in a solvent is then added (block 12 ). Carbon nanotubes are then added to the solution to form the catalyst ink (block 14 ).
Having now presented this general exemplary method, a more detailed exemplary method of preparing a catalyst ink of the invention may be considered. To prepare the ink, 10 mg of catalyst platinum-palladium nanoparticles were mixed with 100 mg of Millipore water and 22 mg of a commercial 5% NAFION solution (Solution technologies 1200 EW). NAFION is a registered trademark of DuPont Chemical Corp., Wilmington, Del., and is a perfluorosulfonic acid copolymer. The inactive portion of the 5% NAFION solution is a solvent such as an alcohol and/or a ketone. When the solvent is removed and the perfluorosulfonic acid copolymer forms a solid, it is useful as a proton-conducting medium.
Although catalyst inks and methods for making catalyst inks of the invention preferably include a proton-conducting material such as NAFION, it will be understood that this is a preferred composition only. The invention may be practiced without such an ingredient. Also, it will be understood that perfluorosulfonic acid polymers and copolymers are preferred proton-conducting materials only, and that many alternatives and equivalents exist. Examples of other proton-conducting materials include acids such as sulfuric acid, sulfonated and phosphated polymers, metal oxides, metal phosphates, metal sulfates, metal hydrates, as well as other materials that are known in the art. The proton-conducting material, with NAFION as an example, may also provide some traditional binder functionality. The catalyst ink of the invention could also be formulated using other binders, with an example being polyannaline.
In the present example, the proton-conducting polymer is added in a weight ratio of about 1:10 to the catalyst particles (22 mg×5% concentration=1.1 mg NAFION). This weight ratio will change depending on factors such as the molecular weight of the catalyst and the proton-conducting polymer, catalyst layer design parameters, and the like. It is believed that weight ranges of between about 1:20 and about 1:2 (proton-conducting polymer:catalyst particle) will prove most useful in practice of the invention, although other weight ranges are also possible.
It will also be appreciated that the present invention may be practiced using any of a variety of catalysts. Metals, and precious metals in particular, are preferred, with Pt and Pd being most preferred examples. Those knowledgeable in the art will appreciate that Pt and Pd are particularly well suited for facilitating the conversion of H 2 molecules to H+ ions and protons, and in facilitating the conversion of H+ ions, electrons and O 2 to H 2 O. The invention could potentially be practiced with other catalysts, however, with known examples including Ir, Ru, Os, Rh, Ni, Co, Mn Mo, W, V, Ce, Ti, Pt/Ru, Pt/Co, Pt/Mn, Pt/Sn, and Pt/Fe. Also, as will be appreciated by those knowledgeable in the art, it may be desirable for economic or other reasons to practice the invention using catalyst particles that are supported on carbon or other materials such as a conducting polymer. It may be economically advantageous, for instance, to use smaller catalyst particles when they are supported on carbon than when they are present in an unsupported state.
In the exemplary method of the invention, the platinum-palladium nanoparticles, water, and NAFION solution are mixed in a sonic bath for 20 minutes. 10 mg of ground nanotubes (Alpha-Aesar 42886) are then added to the ink, and the solution is mixed in an ultrasonic bath. In this example formulation, a weight ratio of about 1:1 (nanotubes:catalyst particles) has been used. A weight ratio of between, about 1:3 and about 3:1 is preferred for practice of the invention. Other weight ratios (nanotubes:catalyst particles) are also believed useful, with particular examples including between about 1:10 and 10:1, between about 1:100 and 100:1, and between about 1:100 and 500:1. A desired weight range may change depending on factors such as the particular catalyst, as well as the size and weight of the particular carbon nanotube selected. Accordingly, it will be appreciated that a wide variety of weight ratio ranges are possible for practice of the invention. The ranges disclosed, however, are believed to be the most useful for typical catalysts and carbon nanotubes.
Useful weight ranges will also depend on the economics of the materials used. That is, one advantage of the invention is that carbon nanotubes can be used to essentially replace more expensive catalyst particles. At some high weight ratio of nanotubes to catalyst particles, however, the large amount of nanotubes used will not offer an economic advantage. At current price levels, for example, weight ratios above about 500:1 when using Pt/Pd catalyst particles offer little economic advantage.
In an exemplary embodiment of a catalyst ink of the present invention, at least about 1% of the catalyst particles are independent of the carbon nanotubes. As used herein, the term “independent” when use in the context of nanotubes and catalyst particles is intended to be broadly interpreted as the particles and nanotubes being unattached to one another. If, for example, a catalyst particle were supported by or were held within a carbon nanotube, it would not be independent of the nanotube.
Preferably, at least about 5% by weight of the catalyst particles are independent of the nanotubes, and more preferably at least about 75% of the catalyst particles are independent of the nanotubes. Also, in a preferred catalyst ink of the invention, at least about 1% by weight of the nanotubes have an unobstructed inner passage. As used herein, the term “unobstructed inner passage” is intended to be broadly interpreted as meaning an inner passage operable to communicate gas. A nanotube that had a particle held in its inner passage and was thus prevented from communicating gas through its inner passage, therefore, would not be considered to be “unobstructed.” More preferred catalyst inks of the invention include at least 10% by weight, and most preferred include at least about 50%, nanotubes with unobstructed inner passages.
In practice, performing separate steps of dispersing the catalyst particles and the carbon nanotubes in the solvent may be useful to ensure that most, if not all, of the catalyst particles remain independent of the carbon nanotubes. Another method step for keeping catalyst particles independent from the nanotubes is to use catalyst particles that have a diameter larger than the inside diameter of the nanotubes used (or using catalyst particles that are on a support that has a diameter larger than the inside diameter of the nanotubes). It will be appreciated that different catalyst particle sizes may be selected depending on different catalyst materials, applications and design parameters. By way of an exemplary size range, catalyst particles may have a diameter of between about 6 and about 20 nanometers. Accordingly, nanotubes in an exemplary invention embodiment may have an inside diameter of less than about 6 nanometers.
Still an additional method step for keeping catalyst particles independent from nanotubes takes advantage of their hydrophobic nature. In particular, if catalyst particles are dispersed in a protic solvent, they should remain independent of the hydrophobic nanotubes. Accordingly, use of protic solvents is preferred in catalyst inks and methods for making catalyst inks of the invention. Those knowledgeable in the art will appreciate that a variety of protic solvents are known. By way of example, solvents having a cohesive energy density (δ) not less than about 10 cal/gm 3 may be protic. When protic solvent are used, nanotubes with an inner passage diameter that is larger than catalyst particle diameters may be used. For example, nanotubes having an inner diameter of between about 5 and about 20 nm may be used with catalyst particles that have a diameter between about 6 and about 10 nm.
A summary of the ingredients and preferred weight ratios of the exemplary ink of the invention is presented in TABLE 1:
Parts by Weight
Material:
Weight:
(Dry Basis*)
Pt/Pd Catalyst nanoparticles
10 mg
10
Water Solvent
100 mg
—
5% Nafion Solution (95%
22 mg (1.1
1.1 (active)
alcohol/Ketone solvent)
mg Nafion)
Carbon nanotubes
10 mg
*Dry Basis - excluding all solvents
It will be appreciated that a catalyst layer of the present invention may be formed by applying a catalyst ink of the invention to a surface and removing the solvent(s) through drying. Accordingly, a catalyst layer of the invention may have the same weight ratios as a catalyst ink of the invention.
FIG. 2 is a cross section of an exemplary catalyst layer 20 of the invention. The layer 20 includes a solid or semi-solid proton conducting polymer 22 that generally defines the layer 20 , a multiplicity of catalyst particles 24 , and a multiplicity of carbon nanotubes 26 . The layer 20 may be formed, for example, when a catalyst ink of the invention is painted or otherwise deposited onto a surface and dried. Drying may occur through application of heat and/or vacuum or partial vacuum, and results in removal of a sufficient amount of the solvent(s) of the catalyst ink to leave the solid or semi-solid catalyst layer 20 .
In operation, the carbon nanotubes 26 provide efficient pathways for gas molecules and electrons to travel through the body of the proton-conducting polymer 22 . Gas molecules may travel through the inner passage of a nanotube 26 at a much faster rate than it would otherwise diffuse through the polymer 22 . Also, it will be appreciated that the nanotubes 26 may have a plurality or multiplicity of holes along its walls through which gas molecules can enter or exit the tube 26 , so that they function in the manner of a “highway” having a multiplicity of entrances and exits. Gas may thereby be efficiently communicated to a catalyst particle 24 that is buried in body of the layer 20 . The nanotubes 26 function in a similar manner in communicating electrons along their walls and in communicating protons. The presence of the nanotubes 26 thereby provides substantial advantages and results in a high efficiency rate for the layer 20 .
In selecting the length of the nanotubes 26 to be used in practice of the invention, the thickness of A of the catalyst layer 20 may be considered. In particular, the length of nanotubes 26 is preferably equal to or greater than the thickness A. Lengths of this magnitude are believed to increase the probability that the nanotubes 26 are exposed to one of the surfaces of the catalyst layer 20 , and thereby provide useful access to that surface. It will be appreciated that a layer thickness A may be selected based on any of a variety of design and/or performance parameters of a particular application. In many applications it is generally desirable to form a relatively thin catalyst layer 20 to minimize the cost of catalyst particles. A minimum thickness A should likewise be maintained, however, to ensure sufficient catalyst exposure.
By way of particular example, an exemplary catalyst layer of the invention may be formed with a thickness A of between about 2 and about 10 microns. Other applications may call for thicker layers. By way of example, mini and micro electronics may use relatively thick layers to maximize catalyst loadings per unit area. In these applications, a thickness A of up to about 500 microns may be useful.
Although FIG. 2 is not drawn to scale, it will be appreciated when considering FIG. 2 that invention embodiments may be practiced using non-uniform mixtures of catalyst particles 24 , nanotubes 26 , and other materials. For example, catalyst particles 24 of different materials and sizes may be included in a layer 20 or ink of the invention. Likewise, nanotubes 26 having different lengths and inside diameters could be used in a layer 20 or ink.
Because at least about 1% of the catalyst particles 24 in catalyst inks of the invention, and preferably at least 75%, are independent of the nanotubes 26 , they will be separated from the tubes 26 by some distance when the ink dries to form the solid catalyst layer 20 . Accordingly, an equal proportion, and most preferably substantially all of, the carbon nanotubes 26 will have generally open and unobstructed inner passages. The particles 24 that were freely dispersed in the ink will be individually embedded in the proton-conducting polymer 22 (and/or other binder if one was provided). As generally illustrated in FIG. 2 , using catalyst particles 24 that have a diameter larger than that of the inside diameter of the carbon nanotubes 26 greatly lowers the likelihood that any particles 24 will become lodged in the tubes 26 .
It will be appreciated that the catalyst particles 24 need not be in direct physical contact in the dried catalyst layer 20 with the proton-conducting polymer 22 or with a nanotube 26 . Indeed, in operation a catalyst particle 24 may be within a thin envelope of fluid such as water, gas, or acid within the proton-conducting polymer 22 and thus be separated by some small distance from the proton-conducting polymer 22 .
It is believed that when the catalyst particles 24 in a catalyst layer 20 of the invention are located within a preferred distance of about 50 nm or less from a carbon nanotube 26 , the catalyst layer 20 will achieve a high level of performance. Although separation distances larger than this preferred distance may be useful for practice of the invention, maintaining the preferred distance as a limit is believed to result in high levels of layer efficiency. Communication of gas, electrons, and protons through the layer 20 may be further enhanced by providing a porous layer 20 .
In addition to catalyst layers, catalyst inks, and methods for preparing catalyst inks, the present invention is also directed to membrane electrode assemblies and to fuel cells. FIG. 3 is a schematic cross section of a membrane electrode assembly (MEA) 50 of the invention. Generally, the MEA 50 includes a polymer electrolyte membrane 52 such as NAFION that has been coated on two opposing surfaces with catalyst layers 54 and 56 of the invention. The enlarged view of the layer 56 shown in FIG. 3 illustrates the carbon nanotubes 58 and catalyst particles 60 that are embedded in the layer.
Operation of the MEA 50 of the invention may be best illustrated through consideration of the schematic cross section of a polymer electrolyte fuel cell (PEMFC) 100 of the invention shown in FIG. 4 . The PEMFC 100 generally includes the MEA 50 , with the addition of a gas permeable anode layer 102 covering the catalyst layer 54 , and the gas permeable cathode layer 104 covering the catalyst layer 56 . The anode layer 102 is operative to communicate fuel gas to the catalyst layer 54 , where the catalyst particles facilitate the conversion of fuel molecules to positively charged fuel ions and free electrons. Free electrons are collected by the current collector 106 and flow to the cathode catalyst layer 56 , and may be exploited in route thereto by a load such as an electrical device 108 .
Advantageously, carbon nanotubes 58 in the catalyst layer 54 of the invention are operative to communicate the fuel gas to catalyst particles 60 that are embedded in the layer 54 and that otherwise would have been much more difficult or impractical for the gas to reach. Likewise, the carbon nanotubes 58 serve to greatly increase the rate of communication of free electrons from embedded catalyst particles 60 to the current collector 106 , and to aid the communication of protons through the layer 54 . As a result of these and other advantages, the catalyst layers 54 and 56 of the invention are able to support high reaction rates while requiring relatively low amounts of catalyst. By way of example, catalyst layers of the invention may be useful with Pt and/or Pd catalyst particles at a coverage of less than about 10 mg/cm 2 .
Further, other exemplary catalyst layers of the present invention may be exploited to provide catalyst layers having high catalyst loadings for applications such as micro and mini electronics in which compact fuel cells are desirable. In particular, it is believed that catalyst layers of the invention may be prepared with catalyst loadings greater than about 12 mg/cm 2 , and of greater than 20 mg/cm 2 .
On the cathode side of the PEMFC 100 , catalyst particles 60 of the catalyst layer 56 facilitate the combination of free electrons, charged fuel ions, and O 2 . Advantageously, the carbon nanotubes 58 of the catalyst layer 56 allow catalyst particles 60 that are embedded in the layer to be readily accessible to O 2 gas and to free electrons. As a result, the catalyst layer 56 achieves a high catalyst activity rate that is preferably at or near to 100%. It will be appreciated that the fuel cell 100 may include additional elements that are well known in the art and have not been illustrated in FIG. 4 for the sake of brevity. For example, manifolds or enclosures may be provided for communicating gas to and from the anode and cathode 102 and 104 .
In order to measure some of the benefits of the invention, a catalyst layer of the invention was prepared using the exemplary catalyst ink prepared using the weight ratios of TABLE 1, and was compared to a control layer of the prior art. In particular, the catalyst ink of the invention was painted onto a carbon electrode in an electrochemical half-cell. Current was applied and measured in the half-cell with a formic acid concentration of 0.1 N. The current after 2 hours was 0.4 milli-amps per milligram of platinum/palladium at 0.4 V with respect to RHE. As a control, a second batch of catalyst ink was prepared as above except that no nanotubes were added. The control catalyst was painted onto a second carbon electrode, and the current was measured in a half-cell using procedures identical to those above. The current after 2 hours was 0.15 milli-amps/milligram of platinum/palladium at 0.4 V with respect to RHE. The results of this experiment suggest that the presence of the nanotubes more than doubled the electrode efficiency.
FIG. 5 illustrates additional experimental data for similar experiments in which a first electrode was painted with a catalyst ink of the invention including nanotubes, while control electrodes were painted with prior art catalyst inks that were identical except that nanotubes were not included. The experimental data suggests that the resultant current is generally a factor of 2 higher for catalyst inks and layers of the invention that include nanotubes.
A formic acid/humidified O 2 fuel cell testing fixture with anode/cathode flow fields machined into conductive graphite blocks was used to further test embodiments of the invention. A membrane electrode assembly (MEA) of the invention was positioned in between the graphite blocks. Temperature and pressure were regulated in the cell. The MEA of the invention had an active cell area of 5 cm 2 . A nanotube catalyst ink of the invention was prepared as described above. The ink was directly painted onto a NAFION 117 membrane. The cathode side for each MEA had a standard loading of 7 mg/cm 2 platinum black (Johnson Matthey). The catalyst loading of the anode was 4 mg/cm 2 of Pt/Pd. A carbon cloth diffusion layer was placed on top of both the cathode and anode catalyst layers. The carbon cloth on the cathode side was Teflon coated for water management.
During the experiments the fuel cell temperature was maintained at 30° C. During normal fuel cell operation, 1 mL/min formic acid was used as the anode fuel and 100 sccm humidified (40° C.) O 2 as the cathode oxidant. The cell polarization curve was measured using a 60 amp fuel cell testing station (available from Fuel Cell Technologies, Inc.). FIG. 6 illustrates a comparison of the test fuel cell polarization (voltage-current) curve for formic acid oxidation for a catalyst layer of the invention (with nanotubes) and for an identical control catalyst layer of the prior art, except that no nanotubes were provided (without nanoparticles). The results of FIG. 6 show that the fuel cell current is about three times higher when for catalyst layers of the present invention as compared to controls of the prior art.
These results demonstrate that current in a fuel cell can be substantially increased through practice of the invention with catalyst inks and layers that include carbon nanotubes. Alternatively, a desired fixed current could potentially be produced using a catalyst ink/layer that used substantially less catalyst particles than was possible in the prior art through the addition of nanotubes.
The present invention thereby provides many advantages and solves many otherwise unresolved problems in the art. For example, inclusion of carbon nanotubes allows for gases and free electrons to be more readily communicated into and through catalyst layers so that catalyst particles embedded in the layers may remain active. As a result, substantially all of the catalyst particles in a layer may be active, with a resultant high efficiency achieved for the catalyst layer and low required catalyst concentration. Electrochemical membrane exchange assemblies and fuel cells that incorporate catalyst layers of the invention may thus be constructed at reduced costs and increased efficiencies.
It is intended that the specific embodiments and configurations herein disclosed are illustrative of the preferred and best modes for practicing the invention, and should not be interpreted as limitations on the scope of the invention as defined by the appended claims. For example, it will be appreciated that although catalyst inks and layers have been illustrated and discussed herein, the present invention has many additional applications. Indeed, the present invention is directed to any solid medium that includes carbon nanotubes operative to communicate gas and/or electrical charge.
Likewise, although catalyst inks and layers have been illustrated including particular materials and components, additional materials and components may be present in other inks and layers of the invention. By way of particular example, materials could be added to provide a degree of porosity to a layer of the invention to further increase its ability to communicate gas, electrons, and protons. Indeed, while particular embodiments of the present invention have been described herein, it will be appreciated by those skilled in the art that many changes and modifications may be made thereto without departing from the invention in its broader aspects and as set forth in the following claims. | A solution useful for forming a solid that supports mass transfer includes carbon nanotubes and a solvent. Solids formed using the solution thereby have carbon nanotubes dispersed therein that are useful for communicating gas and/or electric charges within the solid. Catalyst layers of the invention that include carbon nanotubes can provide high levels of efficiency while requiring low catalyst concentrations. | 7 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention is directed to enhancements for incorporation into an electronic navigation device. More particularly, the present invention is directed to an enhancement of the calibration and hence the accuracy of barometric altimeter measurements with the aid of derived altitudes from a global positioning system.
2. Description of the Related Art
In general, altitude measurements are made using two methods of measurement. One method utilizes a barometric altimeter. Barometric altimeters are devices that sense local atmospheric pressure and use a standard model of the atmosphere to convert this pressure measurement into altitude. Altitude measurements are referenced to height above mean sea level (MSL).
It is well known that local atmospheric pressure at a given altitude varies widely due to the effects of weather, solar heating, and other factors. Thus, in order to provide an accurate altitude, barometric altimeters must be calibrated to correct for these variations. The Global Positioning System (GPS) is a worldwide navigation system that can determine a user's position in horizontal and vertical dimensions. However, GPS vertical measurements are currently all referenced to the WGS-84 ellipsoid, a purely mathematical construct that approximates the shape of the earth. The GPS receiver must use a model that relates the height above the ellipsoid to the height above mean sea level.
Further, it is well known that the vertical measurement of a GPS system is inherently less accurate than the horizontal measurements. This is due to the fact that GPS satellites are constrained to be above the horizon for signal reception to occur. This geometry is less that optimal for measuring the vertical component of a user's location simply because there can not be satellites visible below the user (an optimal configuration would have satellites above and below the user). All GPS receivers are able to take into account satellite geometry (Dilution of Precision) and estimates of other satellite-related errors (URA) and provide a statistical estimate of the errors in the horizontal and vertical measurements.
In practice, a barometric altimeter typically provides a more stable measurement of altitude than GPS over short time periods. However, over long time periods, pressure variations can be of such magnitude that the barometric altimeter measurement of altitude is less accurate than the GPS measurement. The pressure-indicated altitude of an uncalibrated barometric altimeter is typically in error by many tens of meters due to normal atmospheric pressure fluctuations, weather fronts and other sources. However, this error is of a bias like nature—it is slowly varying with time—resulting in less accurate barometric altimeter readings over long time periods. Accordingly, while an altitude determination derived from barometric pressure may be meaningfully accurate in a short time frame, over time, the accuracy of such a determination becomes undesirable. Conversely, because GPS derived altitude suffers from different complementary errors, over a short time period (typically minutes time frame), GPS altitude measurements are subject to much larger variations than barometric altimeter measurements.
In an attempt to overcome the foregoing, one proposal combines a GPS unit and a barometric pressure sensor in the same housing. However, in that proposal the pressure sensor is used to augment GPS derived altitude information.
In particular, McBurney et al., in U.S Pat. No. 6,055,477, disclose a method of combination or integration of measurements made using two systems to provide better availability or accuracy in altitude measurements by estimating a barometric bias using the difference in altitude obtained from the two sources. The McBurney et al. method however, fails to recognize that utilizing the difference between a GPS derived altitude and a barometric altimeter altitude, as a term in calibrating the barometer altimeter, will common mode out any dynamic changes due to movement of the barometric altimeter and the GPS in tandem. As a result, the McBurney et al. approach undesirably requires that the user not change altitude during calibration periods.
Additionally, in the stated prior approach, an altimeter may only be calibrated using GPS derived altitude information when the user is stationary, often referred to as a “Calibration mode”. The present invention makes no distinction between “calibration mode” and “navigation mode”, indeed the barometric error is constantly being estimated and used to calibrate the system. Furthermore, the present invention provides a method to statistically determine the need for calibration which results in both the calibration and error estimation numbers being calculated and utilized without any user intervention, i.e. the user need not place the device in ‘calibration mode’ to obtain the required bias parameter for calibration computations.
There exists a need for a method to take advantage of the long term stability of the GPS altitude measurement and the short term stability of the barometric altimeter measurement to produce an altitude measurement that is stable and accurate over long and short time periods. Additionally, the need exists for a method that uses both GPS-derived altitude and barometric altimeter altitude to produce an altitude measurement that is more stable and accurate than either measurement taken alone. The need also exists for an improved method to calibrate a barometric altimeter and to compute a barometric altitude correction quantity. Particularly, the need exists for a method to have GPS and altimeter outputs to be self calibrating while the user is on the move. The present invention fills the foregoing identified needs, and other needs, while overcoming the drawbacks of the prior art.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide an improved navigation unit.
It is another an object of this invention to compute a barometric altitude correction quantity such that the use of this quantity during calibration results in measurements that are more stable and accurate than GPS or barometric measurements taken independently.
It is another object of the present invention to improve on constraints that are required by prior art methods of various types where there is a user distinction between calibration and navigational modes.
It is a further object of the invention to provide unique options for statistically determining the need for calibration of an altimeter based on discrepancy between GPS altitude measurements and other altitude measurements.
It is another object of the present invention to provide continuous calibration of an altimeter while the unit is on the move.
These and other objects are achieved by a portable unit having an internal processor. Connected to the processor are, at a minimum, an input (such as a keypad), a display, a memory, a barometric pressure sensor, and a GPS receiver, which also connects to an antenna, such as a GPS patch antenna. These components, along with a power supply (such as batteries) are housed within a housing. As will be understood and appreciated, the input and display are accessible at an exterior of the housing, in a conventional manner.
A navigation device incorporating the present invention serves as a GPS unit, in that GPS signals from a plurality of satellites may be received by the GPS receiver, such that the processor calculates position information based upon the received signals. The conventional use and operation of GPS units is well known, and need not be further described.
Additionally, the present invention addresses an altimeter. In particular, the barometric pressure sensor measures barometric pressure and provides the sensed barometric pressure information to the processor. The processor, utilizing stored software, then converts the measured pressure into an altitude, which may be displayed or otherwise communicated to the user. The conversion of barometric pressure to altitude may be accomplished in any desired and conventional manner. For example, a lookup table may be provided in the memory, where the table contains altitude information corresponding to known barometric pressures. Thus, an altitude corresponding with a sensed barometric pressure may be retrieved from memory and displayed on the display. Alternatively and preferably, altitude (or elevation) may be calculated using a known equation.
In particular, the present invention provides a unique navigation device and method for a navigation device that combines data from a plurality of sensors and position information obtained from a GPS, to provide the user with an accurate representation of altitude information. Additionally, as stated, the simultaneous access to GPS information and altimeter information, as well as calculating the difference between that information to obtain an indication of bias, allows for features such as automatic calibration and calibration while the user is on the move.
BRIEF DESCRIPTION OF THE DRAWINGS
The objects and features of the invention noted above are explained in more detail with reference to the drawings, in which like reference numerals denote like elements, and in which:
FIG. 1 is a front view of an illustrative embodiment of a navigation of the present invention;
FIG. 2 is an illustrative block diagram of a navigation device that incorporates the present invention;
FIG. 3 is a graphical representation of a user's elevation trajectory and GPS based and barometric altimeter based elevation readings;
FIG. 4 is a block diagram illustrating barometric altimeter calibration processing according to the present invention; and
FIG. 5 is a block diagram illustrating barometric altimeter calibration processing according to the present invention.
DETAILED DESCRIPTION OF THE INVENTION
With reference initially to FIG. 1, a navigation device that incorporates the present invention is denoted generally by reference numeral 10 . Navigation device 10 has a housing 12 , a display 14 , and an input 16 , preferably a keypad input. Other known inputs, such as a touch screen, may be utilized additionally or alternatively. The housing 12 is preferably sized to be portable, although the invention is not limited to portable units.
With reference to FIG. 2, navigation device 10 has a processor 18 . Connected to processor 18 are a memory 20 , the display 14 , the input 16 and a barometric pressure sensor 22 . Additionally, a GPS receiver 24 is connected to the processor 18 . An antenna 26 , for receiving GPS signals, is connected to the GPS receiver 24 . A power source, such as batteries, or a battery pack (not shown), is utilized to supply power to the various electronic components. Additionally, navigation device 10 may include a port, such as serial data port, for connecting the device 10 to a remote processor or personal computer for uploading information (such as map information) to the device 10 , or for downloading information (such as route information) to a remote processor or personal computer. Alternatively, the device 10 may include wireless communication capabilities, such that data is received wirelessly from a remote site. As will be understood and appreciated, the various electronic components are housed within the housing 12 , such that display 14 and keypad input 16 are accessible at an exterior of the housing.
With reference to FIG. 3, a graphical representation representing a user's elevation trajectory (A), a GPS elevation reading (B), and a barometric altimeter reading (C) is illustrated. In particular, an exemplary elevation profile of a user using navigation device 10 is represented by line A in FIG. 3 In other words, line A represents the trajectory of a user using navigation device 10 as, for example, he or she travels over terrain. The GPS elevation reading is depicted by signal B. As illustrated, the GPS elevation reading B varies over time, as the user moves along the path of use. Similarly, the barometric altimeter reading varies over time from the actual elevation trajectory of the user, although far less significantly, typically, than the GPS elevation reading. Additionally, as illustrated, the barometric altimeter reading is typically offset by a bias amount, or difference D, from the GPS elevation reading.
With reference now to FIGS. 4 and 5, a method of calibrating the altimeter of device 10 is illustrated and described. In accordance with an aspect of the invention, when the processor determines that the difference between the altitude based upon a barometric pressure reading from sensor 30 and GPS derived altitude differs by a selected threshold amount, the processor begins computations necessary to calibrate the barometric readings. In practice, a barometric altimeter typically provides a more stable measurement of altitude than GPS over short time periods (from tens of minutes to several hours). However, over long time periods, pressure variations can be of such magnitude that the barometric altimeter measurement of altitude is less accurate that the GPS measurement. As such, the processor must determine the appropriate altitude, utilizing a combination of these measurements. In particular, as indicated at step 30 , the device is started up and initialized. Processing advances to step 32 , at which the processor 18 measures the difference between an elevation reading provided from the barometric altimeter and an elevation reading provided by the GPS unit. Processing advances to step 34 , at which the processor 18 computes the average between that difference. As will be understood and appreciated, upon the initial measurement at step 32 , the average difference will simply be equal to the difference. As will be further understood, and appreciated, GPS based and barometric altimeter based measurements are taken continuously, or periodically, and on additional passes through this processing loop, the additional information at step 34 is averaged recursively, although other averaging techniques may be employed.
As processing advances to step 36 , processor 18 computes the uncertainty of the average difference determined at step 34 . A decision statistic is employed to make the decision to use the estimated barometer altimeter difference to calibrate the baroaltimeter reading.
At step 38 , the processor 18 determines an average barometer drift for an elapsed time associated with the computed average difference determined at step 34 . In particular, memory 20 preferably has, in table form, the average drift of the barometer over time. Following step 38 , the processing advances to step 40 . At step 40 , processor 18 determines whether the uncertainty of the computed average difference, σ ΔH ave (k), as determined at step 36 , is significantly less than the uncertainty due to baro drift, σ Baro , as obtained at step 38 . In particular, it is determined whether the uncertainty of the computed average difference is less than the determined average barometer drift by a selected threshold. When the uncertainty of the computed average difference σ ΔH ave (k) is not less than σ Baro by at least the threshold amount, processing returns to step 32 , so that the processor may continue taking difference measurements. When, however, it is determined at step 40 that the uncertainty of the computed average difference is less than a preselected threshold than the obtained average barometer drift, processing advances to step 42 .
At step 42 , processor 18 determines whether the elapsed time, that being the time associated with the measurements taken thus far, is greater than a scaled correlation time of GPS vertical errors. When it is determined at step 42 that the elapsed time is not greater than a scaled correlation time of GPS vertical errors, processing returns to step 32 . When, however, it is determined that the elapsed time is greater than a scaled correlation time of GPS vertical errors, processing advances to step 44 . At step 44 , the processor 18 calibrates the barometric altimeter, pursuant to the processing flow of FIG. 5 as discussed below. Following the calibration at step 44 , processing advances to step 46 , where the error statistics of the average difference are reinitiated based upon calibrated barometric altimeter and processing then returns to step 32 .
With reference particularly to FIG. 5, calibration of the barometric altimeter is illustrated and described. At step 48 of FIG. 5, the device 10 of the present invention computes a preliminary calibrated barometrically determined elevation.
The calibration process begins with obtaining a calibrated barometric altitude H B,cal by subtracting the estimated calibration altitude difference from the current barometric altitude i.e. H B,cal (t)=H B (t)−ΔHH cal to remove the bias and thus approximate the true altitude H T (t). This is the approach taken in prior art which is not an optimal approach. The present invention goes further than prior art, by using the calibrated barometric altitude H B,cal to compute a base calibration pressure P B,cal , which is then used to compute local altitude H B .
Processing then advances to step 50 , where the processor 18 computes a calibrated base pressure value P B . The calibrated base pressure P B is determined by solving the following equation for P B , identified as P B,cal . P B , cal = P L [ H B , cal * L T O + 1 ] - g RL
At step 52 , processor 18 computes a calibrated barometric elevation for use in subsequent measurements. In particular, a calibrated barometric elevation, utilizing the computed calibrated base pressure value, P B,cal , is determined according to the following equation: H B , cal = T O L [ ( P L P B , cal ) - RL g - 1 ]
The calibrated barometric elevation is then displayed on display 14 of device 10 , and used in further processing.
Accordingly, the present invention employs a method of estimating the barometric bias using the difference term ΔH ave to common mode out any dynamical changes due to movement of the baro-altimeter and the GPS in tandem which is unique with respect to known methods. In other words, the method of the present invention accounts for the fact that changes in altitude by a user are reflected in both the barometric altitude reading and the GPS altitude reading, thereby allowing calibration to take place while the baro-altimeter and GPS are in motion. A user is not constrained to be motionless during the “calibration mode”. Furthermore, this method allows the barometric error to be continuously estimated and used to calibrate the system when such a need is determined by the previously discussed calibration decision model.
The best known mode for carrying out the present invention utilizes models as described below.
Barometric model
The barometric altitude is modeled by
H B ( t )= H T ( t )+ B B ( t )+ Q B ( t ) (1)
where H B (t) is the barometric pressure indicated altitude, H T (t) is the true altitude in MSL, B B (t) is a slowly varying bias-like term, and Q B (t) is a zero mean Gaussian noise term of variance σ Q 2 . Equation (1) shows that indicated barometric altitude is the sum of the true altitude, plus a bias-like term that is due to the pressure variation of local pressure from the standard atmospheric model, and a noise term that is due to noise of the sensor, A/D, quantization, and other sources.
In order to calibrate the barometric altimeter, the bias term B B (t) must be determined.
GPS Model
GPS altitude is modeled by
H G ( t )= H T ( t )+ B G ( t )+ C G ( t ) (2)
where H G (t) is the GPS altitude (in MSL), B G (t) is a slowly varying bias term due to ionospheric errors, ephemeris errors, satellite clock errors, and other factors, and C G (t) is a zero mean correlated noise term of a much shorter time constant than either B G (t) or B B (t). The variance of the C G (t) process is σ V,GPS 2 and is an estimate of the errors associated with the vertical channel. When Selective Availability was in operation, C G (t) was the largest contributor to GPS altitude error (by far). Also, the B G (t) term is typically much smaller magnitude than the B B (t) term.
Determining Error in Barometric Altitude
One approach to calibrating the baro-altimeter using GPS is to simply perform a difference of equations (1) and (2) at a particular point in time where certain statistical rules (to be discussed later) are met.
H B ( t )− H G ( t )= ΔH ( t )= B B ( t )+ Q B ( t )− B G ( t )− C G ( t ) (3)
Taking the expected value of ΔH(t) yields
Δ H ( t )= B B ( t )− B G ( t ) (4)
since the expected value of terms Q B (t) and C G (t) is zero (they are zero mean noise processes).
One can then calibrate the baro-altimeter using ΔH(t). Calibration is discussed in more detail later.
Because Q B (t) and C G (t) are zero mean random processes, one can reduce the error involved estimating B B (t) by averaging ΔH(t) over many samples. Note that B G (t) is ignored since it is typically small. When estimating a random bias in the presence of additive noise, the variance of the estimate is reduced by the number of samples used to form the estimate only if the additive noise is uncorrelated. Q B (t) is indeed uncorrelated Gaussian noise. However C G (t) is correlated noise with a correlation time of τ C . Therefore the estimation error is treated differently.
One can recursively average ΔH(t) over many samples according to eqn. (5). Δ H ave ( k ) = k - 1 k Δ H ave ( k - 1 ) + 1 k Δ H ( t n ) ( 5 )
The uncertainty of this average estimate is the root sum square of uncertainty reduction in σ Q and the uncertainty reduction to σ V,GPS eqn. (6). σ Δ H ave ( k ) = ( σ Q 2 k + σ V , GPS 2 1 + k * Δ t τ C ) 1 / 2 ( 6 )
where k is the number of samples in the average, and Δt is the interval between samples.
Note that the contribution of a σ V,GPS is reduced according to the correlation time of this process. What this means is that essentially one correlation time must elapse before samples of the C G (t) process are sufficiently decorrelated to contribute an uncertainty reduction equivalent to an independent sample.
It is noted that σ V,GPS is a dynamically changing function, whereas σ Q is a quantity that is chosen a-priori. To accommodate these dynamics, σ V,GPS is also recursively computed over the estimation interval. Again, the same weighting function as used in eqn. (5) is used here σ V , ave ( k ) = k - 1 k σ V , ave ( k - 1 ) + 1 k σ V , GPS ( t n ) ( 7 )
Then σ V,ave (k) is substituted into equation (6). σ Δ H ave ( k ) = ( σ Q 2 k + σ V , ave 2 ( k ) 1 + k * Δ t τ C ) 1 / 2 ( 8 )
Equation (8) is the final form of the uncertainty estimate for ΔH ave .
Decision Statistics For Calibrating Baro-Altimeter
The primary decision statistic to use the baro-altimeter difference estimate ΔH ave (k) to calibrate the baro-altimeter is when
σ ΔH ave ( k )<β*σ Baro ( t n −t cal ) (9)
where β is any non-negative constant and σ Baro (t n −t cal ) is an estimate of the uncertainty to the baro-altimeter. σ Baro is a function of the time that has elapsed since the last calibration and the uncertainty of the calibration. Furthermore, k is constrained so that
k*Δt>α*τ C (10)
which constrains the averaging period to be some multiple α of the correlation time of C G (t).
Also, B B (t) does vary slowly with time. If the averaging period exceeds another time threshold, t max , the assumption that B B (t) is constant does not hold, and the averaging process is re-initialized.
Once the calibration decision statistics have been met, ΔH ave (k) is set equal to ΔH cal , and all recursive estimation algorithms are re-initialized, in particular σ Baro is set equal to σ ΔH,ave .
Approach to Calibrating Barometric Altimeter
The simplest approach to calibration of the baro-altimeter is to simply subtract ΔH cal from the current barometric altitude
H B,cal ( t )= H B ( t )−Δ H cal (11)
This removes the bias B B (t) and thus H B,cal (t) approximates H T (t), the true altitude.
Indeed, this is the approach taken in McBurney, et al. However, this is not the optimal approach. A fundamentally different approach to baro calibration is used in this invention.
Standard Atmosphere Model Relating Pressure to Altitude
For altitude below 11,000 meters, the following equation is used to compute altitude from pressure. H B = T O L [ ( P L P B ) - RL g - 1 ] ( 12 )
where the following quantities are define in the 1993 ICAO Standard Atmosphere Model.
T O =Standard Temperature at Sea Level
L=Lapse rate
R=Gas Constant
g=Acceleration of Gravity
P L =Local Pressure (measured by barometer)
P B =Base pressure (in this case pressure at Sea Level)
H B =Local pressure altitude
From eqn. (12), it is shown that the model that relates pressure to altitude is an exponential model, not a linear model. Thus, if one determines that ΔH cal is 30 meters at a nominal altitude of 500 meters, it does not hold that the proper calibration factor will still be 30 meters at a nominal altitude of 5000 meters. The reason is that 30 meters of elevation difference at 500 meters nominal altitude is a far greater pressure differential than 30 meters of elevation difference at 5000 meters nominal altitude. The calibration method employed in the invention accounts for this discrepancy.
BAROMETRIC ALTIMETER CALIBRATION TECHNIQUE
In this invention during calibration P L is treated as a constant and P B is allowed to vary. The newly computed P B,cal (see eqn. 13) is used in subsequent altitude computations in equation (12).
P B,cal is computed as shown in equation (13). H B,cal is the calibrated barometric altitude estimated using GPS. P B , cal = P L [ H B , cal * L T O + 1 ] - g RL ( 13 )
SUMMARY OF BAROMETRIC ALTIMETER CALIBRATION PROCESS
1. Evaluate equations (9) and (10) to determine if calibration decision statistics are met.
2. If so, compute H B,cal according to eqn. (11).
3. Compute P B,cal according to eqn. (13).
4. Begin computing H B according to (12) using P B,cal .
5. Set σ Baro to σ ΔH,ave .
6. Resume estimation of ΔH ave and σ V,ave (k) using eqns. (5-7).
From the foregoing it will be seen that this invention is one well adapted to attain all ends and objects herein above set forth together with the other advantages which are obvious and which are inherent to the structure.
It will be understood that certain features and sub-combinations are of utility and may be employed without reference to other features and sub-combinations. This is contemplated by and is within the scope of the claims.
Since many possible embodiments may be made of the invention without departing from the scope thereof, it is to be understood that all matter herein set forth or shown in the accompanying drawings is to be interpreted as illustrative, and not in a limiting sense. | A portable, handheld electronic navigation device includes an altimeter and a GPS unit. An internal memory stores cartographic data, for displaying the cartographic data on a display of the navigation device. Accordingly, the device is capable of displaying cartographic data surrounding a location of the unit as determined by GPS and altitude information as determined by the barometric altimeter and GPS. The device provides an enhancement of the calibration and hence the accuracy of barometric altimeter measurements with the aid of derived altitudes from a GPS. The device is able to determine the need for calibration and perform the subsequent computations necessary to facilitate the calibration. Furthermore, the device is able to determine a correction quantity that should be applied to barometric altitude readings, thereby allowing the device to be calibrated while in motion. Both of these features ultimately result in a more accurate determination of altitude. In accordance with an aspect of the invention, the altimeter of the navigation device may be calibrated with altitude information entered by a user, with altitude information obtained from the cartographic, with altitude information derived from GPS or with any combinations thereof. | 6 |
BACKGROUND OF THE INVENTION
[0001] Over the last decade, major advances have been made in the understanding of the biology of the mammalian tachykinin neuropeptides. It is now well established that substance-P (1), neurokinin A (NKA) (2), and neurokinin B (NKB) (3), all of which share a common C-terminal sequence Phe-X-Gly-Leu-Met-NH 2 . (Nakanishi S., Physiol. Rev., 1987;67:117), are widely distributed throughout the periphery and central nervous system (CNS) where they appear to interact with at least three receptor types referred to as NK 1 , NK 2 , and NK 3 , (Guard S., et al., Neurosci. Int., 1991;18:149). Substance-P displays highest affinity for NK 1 receptors, whereas NKA and NKB bind preferentially to NK 2 and NK 3 receptors, respectively. Recently, all three receptors have been cloned and sequenced and shown to be members of the G-protein-linked “super family” of receptors (Nakanishi S., Annu. Rev. Neurosci., 1991;14:123). A wealth of evidence supports the involvement of tachykinin neuropeptides in a variety of biological activities including pain transmission, vasodilation, smooth muscle contraction, bronchoconstriction, activation of the immune system (inflammatory pain), and neurogenic inflammation (Pernow B., Pharmacol. Rev., 1983;35:85). However, to date, a detailed understanding of the physiological roles of tachykinin neuropeptides has been severely hampered by a lack of selective, high affinity, metabolically stable tachykinin receptor antagonists that possess both good bioavailability and CNS penetration. Although several tachykinin receptor antagonists have been described (Tomczuk B. E., et al., Current Opinions in Therapeutic Patents, 1991;1:197), most have been developed through the modification and/or deletion of one or more of the amino acids that comprise the endogenous mammalian tachykinins such that the resulting molecules are still peptides that possess poor pharmacokinetic properties and limited in vivo activities.
[0002] However, since 1991, a number of high-affinity nonpeptide antagonists have been reported. Snider R. M., et al., ( Science, 1991;251:435), and Garret C., et al., ( Proc. Natl. Acad. Sci., 1991;88:10208), described CP-96,345 and RP 67580, respectively, as antagonists at the NK 1 receptor, while Advenier C., et al., ( Brit. J. Pharmacol., 1992;105:78), presented data on SR 48968 showing its high affinity and selectivity for NK 2 receptors. More recently Macleod, et al., ( J. Med. Chem., 1993;36:2044) have published on a novel series of tryptophan derivatives as NK 1 receptor antagonists. It is of interest that most of the nonpeptide tachykinin receptor antagonists described to date arose, either directly or indirectly, out of the screening of large compound collections using a robust radioligand binding assay as the primary screen. Recently, FK 888, a “dipeptide” with high affinity for the NK 1 receptor was described (Fujii J., et al., Neuropeptide, 1992;22:24). Only one NK 3 receptor selective ligand, SR 142801, has been published on to date (Edmonds-Alt, et al., Life Sciences, 1995;56:27).
[0003] International Publication Numbers WO 93/01169, WO 93/01165, and WO 93/001160 cover certain nonpeptide tachykinin receptor antagonists.
[0004] NKB and also NK 3 receptors are distributed throughout the periphery and central nervous system (Maggi, et al., J. Auton. Pharmacol., 1993;13:23). NKB is believed to mediate a variety of biological actions via the NK 3 receptor including gastric acid secretion; appetite regulation; modulation of serotonergic, cholinergic, and dopaminergic systems; smooth muscle contraction and neuronal excitation. Recent publications descriptive of this art include Polidor, et al., Neuroscience Letts., 1989;103:320; Massi, et al., Neuroscience Letts., 1988;92:341, and Improta, et al., Peptides, 1991;12:1433. Due to its actions with dopaminergic (Elliott, et al., Neuropeptides, 1991;19:119), cholinergic (Stoessl, et al., Psycho. Pharmacol., 1988;95:502), and serotonergic (Stoessl, et al., Neuroscience Letts., 1987;80:321) systems, NKB may play a role in psychotic behavior, memory functions, and depression.
[0005] Accordingly, compounds capable of antagonizing the effects of NKB at NK 3 receptors will be useful in treating or preventing a variety of disorders including pain, depression, anxiety, panic, schizophrenia, neuralgia, addiction disorders, inflammatory diseases; gastrointestinal disorders including colitis, Crohn's disease, inflammatory bowel disorder, and satiety; vascular disorders such as angina and migraine and neuropathological disorders such as Parkinsonism and Alzheimer's.
SUMMARY OF THE INVENTION
[0006] The instant invention is a compound of formula
[0007] or a pharmaceutically acceptable salt thereof wherein:
[0008] R 1 is straight or branched alkyl of from 5 to 15 carbon atoms, aryl, or heteroaryl;
[0009] R 2 is hydrogen, hydroxy, amino, or thiol;
[0010] R 3 is aryl, arylsulfonylmethyl, or saturated or unsaturated heterocycle;
[0011] R 4 is from 1 to 4 groups each independently selected from halogen, alkyl, hydroxy, and alkoxy;
[0012] n is an integer of from 2 to 6; and the (CH 2 ) group can be replaced by oxygen, nitrogen, or sulphur.
[0013] Preferred compounds of the invention are those of Formula I wherein:
[0014] R 1 is phenyl, naphthyl, piperidinyl, imidazolyl, or tetrazole;
[0015] R 2 is hydrogen, hydroxy, or amino;
[0016] R 3 is phenyl, fluorophenyl, hydroxyphenyl, or phenylsulfonylmethyl;
[0017] R 4 is dichloro, difluoro, dimethoxy, or dimethyl; and
[0018] n is an integer of from 2 to 6.
[0019] More preferred compounds of the invention are those of Formula I wherein:
[0020] R 1 is phenyl, naphthyl, piperidinyl, or imidazolyl;
[0021] R 2 is hydrogen or hydroxy;
[0022] R 3 is phenyl, 4-fluorophenyl, 4-hydroxyphenyl, or phenylsulfonylmethyl;
[0023] R 4 is 3,4-dichlorophenyl; and
[0024] n is the integer 2 to 4.
[0025] Still more preferred compounds of the instant invention are those of Formula I wherein:
[0026] R 1 is phenyl;
[0027] R 2 is hydrogen or hydroxy;
[0028] R 3 is phenylsulfonylmethyl or phenyl;
[0029] R 4 is 3,4-dichloro; and
[0030] n is 3.
[0031] The most preferred compounds of the invention are selected from but not limited to:
[0032] (R)-{3-(3,4-Dichloro-phenyl)-3-[3-(4-phenyl-piperidin-1-yl)-propyl]-piperidin-1-yl}-phenyl-methanone monohydrochloride;
[0033] (S)-{3-(3,4-Dichloro-phenyl)-3-[3-(4-hydroxy-4-phenyl-piperidin-1-yl)-propyl]-piperidin-1-yl}-phenyl-methanone monohydrochloride;
[0034] (S)-[3-[3-(4-Benzenesulfonylmethyl-4-hydroxy-piperidin-1-yl)-propyl]-3-(3,4-dichloro-phenyl)-piperidin-1-yl]-phenyl-methanone monohydrochloride;
[0035] (R)-{3-(3,4-Dichloro-phenyl)-3-[3-(4-hydroxy-4-phenyl-piperidin-1-yl)-propyl]-piperidin-1-yl}-naphthalene-2-yl-methanone;
[0036] (R)-{3-(3,4-Dichloro-phenyl)-3-[3-(4-hydroxy-4-phenyl-piperidin-1-yl)-propyl]-piperidin-1-yl}-pyridin-4-yl-methanone;
[0037] N-(1-{3-[3-(3,4-Dichloro-phenyl)-1-(1H-imidazole-2-carbonyl)-piperidin-3-yl]-propyl}-4-phenyl-piperidin-4-yl)-acetamide;
[0038] (R)-{3-(3,4-Dichloro-phenyl)-3-[3-(4-hydroxy-4-phenyl-piperidin-1-yl)-propyl]-piperidin-1-yl}-phenyl-methanone;
[0039] (R)-{3-(3,4-Dichloro-phenyl)-3-[3-(4-phenyl-piperidin-1-yl)-propyl]-piperidin-1-yl}-phenyl-methanone;
[0040] (3-(3,4-Dichloro-phenyl)-3-{3-[4-(4-fluoro-phenyl)-4-hydroxy-piperidin-1-yl]-propyl}-piperidin-1-yl)-phenyl-methanone;
[0041] [3-[3-(4-Benzenesulfonylmethyl-4-hydroxy-piperidin-1-yl)propyl]-3-(3,4-dichloro-phenyl)-piperidin-1-yl]-phenyl-methanone;
[0042] {3-(4-Fluoro-phenyl)-3-[3-(4-hydroxy-4-phenyl-piperidin-1-yl)-propyl]-piperidin-1-yl}-phenyl-methanone;
[0043] {3-(3,4-Dimethoxy-phenyl)-3-[3-(4-hydroxy-4-phenyl-piperidin-1-yl)-propyl]-piperidin-1-yl}-phenyl-methanone;
[0044] {3-(3,4-Dimethyl-phenyl)-3-[3-(4-hydroxy-4-phenyl-piperidin-1-yl)-propyl]-piperidin-1-yl}-phenyl-methanone;
[0045] [3-[3-(4-Hydroxy-4-phenyl-piperidin-1-yl)-propyl]-3-(3,4,5-trichloro-phenyl)-piperidin-1-yl]-phenyl-methanone;
[0046] {3-(3,4-Dichloro-phenyl)-3-[4-(4-hydroxy-4-phenyl-piperidin-1-yl)-butyl]-piperidin-1-yl}-phenyl-methanone;
[0047] {3-(3,4-Dichloro-phenyl)-3-[6-(4-hydroxy-4-phenyl-piperidin-1-yl)-hexyl]-piperidin-1-yl}-phenyl-methanone;
[0048] [3-{2-[(4-Benzenesulfonylmethyl-4-hydroxy-piperidin-1-ylmethyl)-amino]-ethyl}-3-(3,4-dichloro-phenyl)-piperidin-1-yl]-phenyl-methanone;
[0049] [3-{2-[(4-Benzenesulfonylmethyl-4-hydroxy-piperidin-1-ylmethyl)-methyl-amino]-ethyl}-3-(3,4-dichlorophenyl)-piperidin-1-yl]-phenyl-methanone;
[0050] [3-[2-(4-Benzenesulfonylmethyl-4-hydroxy-piperidin-1-ylmethoxy)-ethyl]-3-(3,4-dichlorophenyl)-piperidin-1-yl]-phenyl-methanone;
[0051] [3-[2-(4-Benzenesulfonylmethyl-4-hydroxy-piperidin-1-ylmethylsulfanyl)-ethyl]-3-(3,4-dichloro-phenyl)-piperidin-1-yl]-phenyl-methanone;
[0052] (3-(3,4-Dichloro-phenyl)-3-{2-[(4-hydroxy-4-phenyl-piperidin-1-ylmethyl)-amino]-ethyl}-piperidin-1-yl)-phenyl-methanone;
[0053] (3-(3,4-Dichloro-phenyl)-3-{2-[(4-hydroxy-4-phenyl-piperidin-1-ylmethyl)-methyl-amino]-ethyl}-piperidin-1-yl)-phenyl-methanone;
[0054] {3-(3,4-Dichloro-phenyl)-3-[2-(4-hydroxy-4-phenyl-piperidin-1-ylmethoxy)-ethyl]-piperidin-1-yl}-phenyl-methanone;
[0055] {3-(3,4-Dichloro-phenyl)-3-[2-(4-hydroxy-4-phenyl-piperidin-1-ylmethylsulfanyl)-ethyl]-piperidin-1-yl}-phenyl-methanone;
[0056] [3-{[2-(4-Benzenesulfonylmethyl-4-hydroxy-piperidin-1-yl)-ethylamino]-methyl)-3-(3,4-dichloro-phenyl)-piperidin-1-yl]-phenyl-methanone;
[0057] [3-[2-(4-Benzenesulfonylmethyl-4-hydroxy-piperidin-1-yl)-ethyl]-methyl-amino}-methyl)-3-(3,4-dichloro-phenyl)-piperidin-1-yl]-phenyl-methanone;
[0058] [3-[2-(4-Benzenesulfonylmethyl-4-hydroxy-piperidin-1-yl)-ethoxymethyl]-3-(3,4-dichlorophenyl)-piperidin-1-yl]-phenyl-methanone;
[0059] [3-[2-(4-Benzenesulfonylmethyl-4-hydroxy-piperidin-1-yl)-ethylsulfanylmethyl]-3-(3,4-dichloro-phenyl)-piperidin-1-yl]-phenyl-methanone;
[0060] (3-(3,4-Dichloro-phenyl)-3-{[2-(4-hydroxy-4-phenyl-piperidin-1-yl)-ethylamino]-methyl}-piperidin-1-yl)-phenyl-methanone;
[0061] [3-(3,4-Dichloro-phenyl)-3-{[2-(4-hydroxy-4-phenyl-piperidin-1-yl)-ethyl]-methyl-amino}-methyl)-piperidin-1-yl]-phenyl-methanone;
[0062] {3-(3,4-Dichloro-phenyl)-3-[2-(4-hydroxy-4-phenyl-piperidin-1-yl)-ethoxymethyl]-piperidin-1-yl}-phenyl-methanone;
[0063] {3-(3,4-Dichloro-phenyl)-3-[2-(4-hydroxy-4-phenyl-piperidin-1-yl)-ethylsutfanylmethyl]-piperidin-1-yl}-phenyl-methanone;
[0064] [3-[(4-Benzenesulfonylmethyl-4-hydroxy-piperidin-1-ylmethyl)-amino]-3-(3,4 dichloro-phenyl)piperidin-1-yl]-phenyl-methanone;
[0065] [3-[2-(4-Benzenesulfonylmethyl-4-hydroxy-piperidin-1-yl)-ethylamino]-3-(3,4-dichlorophenyl)-piperidin-1-yl]-phenyl-methanone;
[0066] [3-[3-(4-Benzenesulfonylmethyl-4-hydroxy-piperidin-1-yl)-propylamino]-3-(3,4-dichlorophenyl)-piperidin-1-yl]-phenyl-methanone;
[0067] [3-[(4-Benzenesulfonylmethyl-4-hydroxy-piperidin-1-ylmethyl)-methyl-amino]-3-(3,4-dichlorophenyl)-piperidin-1-yl]-phenyl-methanone;
[0068] [3-{[2-(4-Benzenesulfonylmethyl-4-hydroxy-piperidin-1-yl)-ethyl]-methyl-amino}-3-(3,4-dichloro-phenyl)-piperidin-1-yl]-phenyl-methanone;
[0069] [3-{[3-(4-Benzenesulfonylmethyl-4-hydroxy-piperidin-1-yl)-propyl]-methyl-amino}-3-(3,4-dichloro-phenyl)-piperidin-1-yl]-phenyl-methanone;
[0070] [3-(4-Benzenesulfonylmethyl-4-hydroxy-piperidin-1-ylmethoxy)-3-(3,4-dichloro-phenyl)-piperidin-1-yl]-phenyl-methanone;
[0071] [3-[2-(4-Benzenesulfonylmethyl-4-hydroxy-piperidin-1-yl)-ethoxy]-3-(3,4-dichlorophenyl)-piperidin-1-yl]-phenyl-methanone;
[0072] [3-[3-(4-Benzenesulfonylmethyl-4-hydroxy-piperidin-1-yl)-propoxy]-3-(3,4-dichlorophenyl)-piperidin-1-yl]-phenyl-methanone;
[0073] [3-(4-Benzenesulfonylmethyl-4-hydroxy-piperidin-1-ylmethylsulfanyl)-3-(3,4-dichlorophenyl)-piperidin-1-yl]-phenyl-methanone;
[0074] [3-[2-(4-Benzenesulfonylmethyl-4-hydroxy-piperidin-1-yl)-ethylsulfanyl]-3-(3,4-dichlorophenyl)-piperidin-1-yl]-phenyl-methanone;
[0075] [3-[3-(4-Benzenesulfonylmethyl-4-hydroxy-piperidin-1-yl)-propylsulfanyl]-3-(3,4-dichlorophenyl) piperidin-1-yl]-phenyl-methanone;
[0076] {3-(3,4-Dichloro-phenyl)-3-[(4-hydroxy-4-phenyl-piperidin-1-ylmethyl)-amino]-piperidin-1-yl}-phenyl-methanone;
[0077] {3-(3,4-Dichloro-phenyl)-3-[2-(4-hydroxy-4-phenyl-piperidin-1-yl)-ethylamino]-piperidin-1-yl}-phenyl-methanone;
[0078] {3-(3,4-Dichloro-phenyl)-3-[3-(4-hydroxy-4-phenyl-piperidin-1-yl)-propylamino]-piperidin-1-yl}-phenyl-methanone;
[0079] {3-(3,4-Dichloro-phenyl)-3-[(4-hydroxy-4-phenyl-piperidin-1-ylmethyl)-methyl-amino]-piperidin-1-yl}-phenyl-methanone;
[0080] (3-(3,4-Dichloro-phenyl)-3-{[2-(4-hydroxy-4-phenyl-piperidin-1-yl)-ethyl]-methyl-amino}-piperidin-1-yl)-phenyl-methanone;
[0081] (3-(3,4-Dichloro-phenyl)-3-{[3-(4-hydroxy-4-phenyl-piperidin-1-yl)-propyl]-methyl-amino}-piperidin-1-yl)-phenyl-methanone;
[0082] [3-(3,4-Dichloro-phenyl)-3-(4-hydroxy-4-phenyl-piperidin-1-ylmethoxy)-piperidin-1-yl]-phenyl-methanone;
[0083] {3-(3,4-Dichloro-phenyl)-3-[2-(4-hydroxy-4-phenyl-piperidin-1-yl)-ethoxy]-piperidin-1-yl}-phenyl-methanone;
[0084] {3-(3,4-Dichloro-phenyl)-3-[3-(4-hydroxy-4-phenyl-piperidin-1-yl)-propoxy]-piperidin-1-yl}-phenyl-methanone;
[0085] [3-(3,4-Dichloro-phenyl)-3-(4-hydroxy-4-phenyl-piperidin-1-ylmethylsulfanyl)-piperidin-1-yl]-phenyl-methanone;
[0086] {3-(3,4-Dichloro-phenyl)-3-[2-(4-hydroxy-4-phenyl-piperidin-1-yl)-ethylsulfanyl]-piperidin-1-yl}-phenyl-methanone; and
[0087] {3-(3,4-Dichloro-phenyl)-3-[3-(4-hydroxy-4-phenyl-piperidin-1-yl)-propylsulfanyl]-piperidin-1-yl}-phenyl-methanone.
[0088] Another aspect of the invention is a pharmaceutical composition containing one or more compound of Formula I above in a therapeutically effective amount together with a pharmaceutically acceptable carrier
[0089] The compounds of the invention are useful in the treatment of central nervous system disorders such as anxiety, emesis, depression, psychoses, and schizophrenia. They are also useful in the treatment of inflammatory disease, pain, migraine, asthma, and emesis. They are also useful in the treatment of Alzheimer's disease and Parkinsonism.
DETAILED DESCRIPTION
[0090] The compounds of the instant invention are selective tachykinin NK 3 receptor antagonists. These are small compounds which have the advantage of good bioavailability.
[0091] The compounds of Formula I are as described above.
[0092] The term “alkyl” is a straight, branched, or unsaturated group of from 5 to 15 carbon atoms such as n-pentyl, n-hexyl, 2,2-dimethyldodecyl, isopentyl, n-heptyl, n-octyl, n-nonyl, undecyl, dodecyl, 3,4-alkene, 2-tetradecyl, and the like unless otherwise stated.
[0093] The term “aryl” is a phenyl, or naphthyl group which may be unsubstituted or substituted with from 1 to 4 groups each independently selected from halogen, alkyl, alkoxyl, and hydroxy.
[0094] The term “heteroaryl” (or heterocycle) includes compounds containing nitrogen, oxygen, and/or sulfur. Such groups include but are not limited to pyrazole, isoxazole, imidazole, furan, thiophene, pyrrole, tetrazole, and thiazole. Each group may be unsubstituted or substituted with from 1 to 4 groups each independently selected from halogen, alkyl, alkoxyl, and hydroxy.
[0095] The term “arylsulfonylmethyl” is as described above for aryl with a sulfonylmethyl attached. Such groups as subtituted phenyl or hetroaryl are examples.
[0096] The term “halogen” is fluorine, chlorine, bromine, and iodine. The preferred halogens are chlorine and fluorine.
[0097] The term amino refers to unsubstituted mono- or disubstituted groups. The substituents are as described for alkyl above. Preferred substituents are methyl and ethyl.
[0098] The compounds of this invention are selective NK 3 antagonists. Their activities can be demonstrated by the following assays.
[0099] 1. Receptor Binding in Transfected CHO Cells
[0100] CHO cells expressing either human NK 1 or NK 3 receptors were cultured in Ham's F-12 Nutrient Mixture supplemented with 10% fetal call serum and 1% penicillin/streptomycin. Cells were seeded to 96-well Wallac (Gaithersburg, Md.) rigid crosstalk corrected cell culture plate 1 day before experiment. On the day of each experiment, cells were washed twice with phosphate buffered saline (PBS) and appropriate agonists or antagonists were added and incubated in 0.2 nM 125 I-labeled ligand in PBS containing 0.4 mg/mL BSA, 0.08 mg/mL bacitracin, 0.004 mg/mL chymostatin, 0.004 mg/mL leupeptin, 1 μM thiorphan, 25 μM phosphoramidon, and 2 mM MnCl 2 . The cells were incubated for 1 hour at room temperature and the reactions terminated by two washes with ice cold PBS. Fifty microliters of 2% SDS followed by 175 μL of Ready Gel (Beckman) were added to each well. Plates were vortexed, and the radioactivity was quantified in a Wallac 1450 microbeta scintillation counter. Nonspecific binding was determined in the presence of 1 μM unlabeled corresponding ligand. Receptor binding data were analyzed with nonlinear curve fitting using KaleidaGraph software package (PCS Inc., Reading, Pa.). IC 50 values were determined using a modified Hill equation,
% inhibition = cpm ( L ) - cpm ( 1 μM cold ligand ) cpm ( 0 ) - cpm ( 1 μM cold ligand ) = L n IC 50 n + L n ,
[0101] where cold ligand represents unlabeled ligand, L represents the concentration of unlabeled ligand, n the Hill coefficient, and IC 50 the concentration of unlabeled ligand that causes 50% inhibition of the total specific binding of 0.2 nM radiolabeled ligand.
[0102] The compounds as exemplified in Table 1 have been shown to displace radioligand for the NK 3 receptor at a concentration range of 6 to 18 nM, whereas their affinities for the NK 1 receptor are much lower. Detailed data is provided in Table 1.
TABLE 1 IC 50 (nM) Compounds Binding to Human Binding to Human (See Scheme 3) NK 3 Receptors NK 1 Receptors 20-3 17.8 ± 1.5 694 ± 89 20-1 5.9 ± 0.4 >1000 20-2 6.2 ± 0.6 >1000
[0103] 2. Inhibition of Phosphatidylinositol Turnover in Transfected CHO Cells
[0104] The inhibitory effects of these compounds on agonist-induced phosphatidylinositol turnover was estimated by measuring their effects on inositol phosphates (IP) accumulation in CHO cells expressing NK 3 receptors. Briefly, cells (10,000/well) were seeded in 96-well cell culture plates 24 hours before changing medium to EMEM/F-12 (w/Earle's salt, w/glutamine; GIBCOL) containing 10 μCi/mL [ 3 H]inositol. After overnight incubation with [ 3 H]inositol, medium was removed and cells were washed twice with assay buffer (MEM with 10 mM LiCl, 20 mM HEPES, and 1 mg/mL BSA). Cells were then incubated with various concentrations of agonists with or without 1 μM of tested compounds for 1 hour. Reactions were stopped by two washes with ice-cold PBS followed by the addition of 0.1 mL ice-cold 5% TCA to each well. The TCA extract was applied to a cation exchange column containing AG 1-X8 resin (Bio-Rad) and washed three times with 5 mM myo-inositol. Inositol phosphates (IP) was eluted with 1 M ammonium formate/0.1 M formic acid. Radioactivity was determined by liquid scintillation counting. Data were analyzed with nonlinear curve fitting using KaleidaGraph software package (PCS Inc, Reading, Pa.). The pKB values in Table 2 were calculated according to the formula: pKB=log(dose ratio−1)−log[B].
TABLE 2 Compounds pKB 20-3 7.9 ± 0.3 20-1 8.2 ± 0.4 20-2 8.3 ± 0.5
[0105] In conclusion, data presented in Table 1 (binding assay) and in Table 2 (functionial assay) demonstrate that the compounds of the invention are potent and selective antagonists for the human tachykinin NK 3 receptor.
TABLE 3 Mean (SD) Pharmacokinetic Parameters of NK3 Receptor Antagonists in Male Wistar Rats Receiving an Oral Dose of ˜20 mg/kg tmax t½ AUC(0-tldc) Compounds N (hr) Cmax (ng/mL) (hr) (ng · hr/mL) F (%) 20-2 3 1.3 125.4 (8.0) 7.4 716 (56) — (0.6) (1.3) 20-3 3 1.8 107 (44) — 572 (174) — (1.9) 20-1 3 1.3 74.0 (12.9) — 366 (140) — (0.6) SR 142801 a 3 1.8 133 (49) 5.3 703 (213) — (1.9) (1.5)
[0106] The compounds of the invention are equal to the reference standard in the pharmacokinetic parameters studied. This indicates that compounds of this type will provide desirable pharmaceuticals with bioavailability.
[0107] General Procedure for Preparing Intermediate and Final Products of the Invention
[0108] The synthesis of intermediate (A) is shown in Scheme I below. The reaction of 3-bromopropanol (1) with dihydropyran and catalytic amount of p-toluenesulfonic acid gave quantitative yield of THP protected alcohol (2). Deprotonation of 3,4-dichlorophenylacetonitrile (3) with NaH in THF at room temperature followed by the addition of (2) to the mixture gave the alkylation product (4) in 82% yield. A second alkylation of (4) using KHMDS as base at −78° C. in THF, and ethyl 3-bromopropionate gave ester (5) in 94% yield. Catalytic hydrogenation with Raney Ni and NH 4 OH, in ethanol for 2 days, reduced the cyano group of (5) to amine, which then cyclized with the ester to give lactam (6) in 85% yield. Reduction of the piperidone (6) with LAH gave the corresponding piperidine (7). The THP group was removed by HCl in dry ether, and the resulting racemic hydroxy piperidine (8) was resolved with (S)-(+)-camphorsulfonic acid in iPrOH to give the diastereomeric salt, with >94% ee of (R)-(+)-(9) in 32% yield. The (R)-(+)-(9) salt was then treated with PhCOCl and iPr 2 NEt in CH 2 Cl 2 to give N-benzoyl amide (10) in 90% yield. The primary hydroxy group of (10) was then converted to iodide by mesylation, and iodization, to give intermediate (A).
[0109] The synthesis of intermediate (B) is shown in Scheme II below, started from piperidone hydrate hydrochloride and methylphenylsulfone in the presence of n-BuLi after piperidone was protected by BOC group, and then the BOC protection was removed by TFA solution to obtain Compound B-2. The N-benzyl-4-hydroxy-4-phenyl piperidine was hydrogenated to give B-3.
[0110] The coupling of iodide (A) and substituted piperidine (B)-HCl was performed with KHCO 3 in MeCN at 60° C. for 20 hours to give the expected product. See Scheme III below.
EXPERIMENTS
[0111] 2-(3,4-Dichloro-phenyl)-5-(tetrahydro-pyran-4-yloxy)-pentanenitrile (4)
[0112] To a suspension of NaH (7.6 g, 0.191 mol) in THF (90 mL) was added slowly a solution of 3,4-dichloro-phenylacetonitrile (32.3 g, 0.174 mol) in dry THF (40 mL). The mixture was stirred at room temperature for 2 hours, then cooled in dry ice-acetone bath. A solution of THP protected 3-bromopropanol (42.6 g, 0.191 mol, 1.1 eq) in dry THF (50 mL) was added dropwise to this solution. After the addition was completed, the reaction was warmed to room temperature and stirred at room temperature overnight (20 hours). The reaction was then quenched with saturated NH 4 Cl solution (ca. 5 mL) and ether (300 mL) was added. The organic phase was then washed with saturated NaHCO 3 , brine, and dried (MgSO 4 ). After filtration, solvent was removed, and the crude oil was purified by flash column chromatography (Hexane-AcOEt/8:1). The product weight 46.8 g (82.2%) as light yellow oil.
[0113] 4-Cyano-4-(3,4-dichlorophenyl)-7-(tetrahydropyran-4-yloxy)-heptanoic Acid Ethyl Ester (5)
[0114] Potassium hexamethyldisilazide (0.5 M in toluene, 285 mL, 0.143 mol) was added dropwise to a solution of (4) (39 g, 0.119 mol) in THF (240 mL) under nitrogen and stirred at room temperature for 1 hour. A solution of ethyl 3-bromopropionate (22.8 mL, 0.178 mol, 1.5 eq) in THF (45 mL) was added to the reaction mixture all at once. After stirring at room temperature for 4 hours, the reaction was quenched with saturated NH 4 Cl solution (20 mL). The organic solution was dried over MgSO 4 , and solvent is evaporated. The crude oil was purified by flashed chromatography (hexane-AcOEt/8:1) to give light yellow oil (48.03 g, 94.4% yield).
[0115] 5-(3,4-Dichlorophenyl)-5-[3-(tetrahydropyran-4-yloxy)-propyl]-2-piperidone (6)
[0116] Raney Ni is added to a solution of cyanoester (5) (8.5 g, 19.84 mmol) in absolute EtOH (200 mL) and concentrated NH 4 OH (40 mL), The mixture was subjected to a H 2 (51.8 psi) Par for 64.5 hours. The reaction mixture was filtered through celite, and N 2 gas was passed through the solution to remove NH 3 . EtOH was then evaporated, and water is azeotropically removed with toluene. The crude oil is purified by flash chromatography (Ch 2 Cl 2 —MeOH/95:5) to give a colorless solid (6.5 g, 84.8% yield), mp ˜45° C.
[0117] 3-(3,4-Dichlorophenyl)-3-[3-(tetrahydropyran-4-yloxy)-propyl]-piperidine (7)
[0118] Piperidone (6) (42.9 g, 0.111 mol) in dry THF (300 mL) was added to a suspension of LAH (8.4 g, 0.222 mol) in dry THF (500 mL), which was then heated under N 2 at 60° C. in an oil bath for 5 hours, then cooled and stirred at room temperature overnight (20 hours). The reaction was quenched by H 2 O (8.5 mL), 4N NaOH (8.5 mL), and H 2 O (0.5 mL), respectively. White solid was filtered and washed with Et 2 O. The filtrate was concentrated, and the crude oil was purified by flash chromatography (CH 2 Cl 2 —MeOH/95:5) to give a colorless oil (37.94 g 91.8%).
[0119] 3-[3-(3,4-Dichlorophenyl)-piperidin-3-yl]-propan-1-ol (8)
[0120] A solution of dry HCl.OEt 2 was added to a solution of piperidine (7) (20.2 g, 54.36 mmol) in MeOH (200 mL) until pH ˜1. The mixture was stirred at room temperature for 30 minutes. Solvent was evaporated, the residue was dissolved in CH 2 Cl 2 (300 mL) and stirred with 1N NaOH (100 mL) for 15 minutes. The solvent was separated, washed with NaHCO 3 , and dried over MaSO 4 . The crude oil was purified by flash chromatography (CH 2 Cl 2 —MeOH(saturated with NH 3 )/95:5) to give a white solid (13.25 g, 84.6%).
[0121] (R)-3-[3-(3,4-Dichlorophenyl)-piperidin-3-yl]-propan-1-ol(1s)-7,7-dimethyl-2-oxobicyclo[2.2.1]heptane-1-methanesulfonate (1:1) Salt (9)
[0122] A solution of (S)-(+)-camphorsulfonic acid (10.3 g, 44.41 mmol) in iPrOH (10 mL) was added to a solution of hydroxy piperidine (8) (12.8 g, 44.41 mmol) in iPrOH. The mixture was heated to reflux for 15 minutes. The solvent was removed to give glassy solid 23.4 g, which solid was then recrystallized in iPrOH two times to give white crystals (5.5 g, 23.8%, 95% ee), mp 188-189° C.
[0123] [3-(3,4-Dichlorophenyl)-3-(3-hydroxy-propyl)-piperidin-1-yl]-phenyl-methanone (10)
[0124] Diisopropylethylamine (5.7 mL, 3.27 mmol, 5.0 eq) was added to a mixture of camphorsulfonate salt (9) (3.4 g, 6.53 mmol) in CH 2 Cl 2 (21 mL, 0.3 M) and followed by dropwise addition of PhCOCl (0.83 mL, 7.19 mmol, 1.1 eq). The solution was stirred at room temperature for 1 hour. The reacting mixture was diluted with CH 2 Cl 2 (200 mL) and washed with brine, 1 M KHSO 4 , and saturated NaHCO 3 then dried over MgSO 4 . The concentrated crude oil was purified by flash chromatography (CH 2 Cl 2 —MeOH/95:5) to give white solid (2.30 g, 89.8%).
[0125] (R)-Methanesulfonic acid 3-[1-benzoyl-3-(3,4-dichloro-phenyl)-piperidin-3-yl]-propyl Ester (11)
[0126] Diisopropylethylamine (1.6 mL, 9.18 mmol) was added to a solution of alcohol (10) (1.2 g, 3.06 mmol 3.0 eq) in CH 2 Cl 2 (30 mL) followed by MsCl (0.28 mL, 3.67 mmol, 1.2 eq). The solution was stirred at room temperature for 2 hours, then quenched with water and diluted with CH 2 Cl 2 (200 mL). The organic layer was washed with brine, 1N HCl, saturated NaHCO 3 , and dried over MgSO 4 . The crude oil was purified by flash chromatography (CH 2 Cl 2 —MeOH/95:5) to give light yellow solid (1.43 g, 99.3%).
[0127] (R)-[3-(3,4-Dichlorophenyl)-3-(3-iodopropyl)-piperidin-1-yl]-phenyl-methanone (A)
[0128] A solution of KI (2.6 g, 15.43 mmol, 1.1 eq) in acetone (10 mL) was added to a solution of mesylate (11) (6.6 g, 14.03 mmol) in dry acetone (80 mL) plus a drop of Hg. The mixture was heated at reflux (70° C. oil bath) for 18 hours and white solid formed. Acetone was evaporated, the remaining solid was extracted with CH 2 Cl 2 . The combined CH 2 Cl 2 extracts were washed with brine, then dried over MgSO 4 . The crude oil was purified by flash chromatography (hexane-EtOAc/2:1) to give a colorless oil, which solidified after dried at 45° C., 20 mm Hg overnight. The solid weight 6.93 g (98.4%), mp 118-120° C.
[0129] {3-[3-(4-Benzensulfonylmethyl-4-hydroxy-piperidin-1-yl]-3-(3,4-dichlorophenyl)-piperidin-1-yl}-phenyl-methanone Monohydrochloride (20-1)
[0130] A mixture of TFA salt (B-1) (0.26 g, 0.72 mmol), iodide (0.3 g, 0.60 mmol), and KHCO 3 (0.3 g, 2.99 mmol) in CH 3 CN (10 mL) was heated at 60° C. oil bath for 18 hours, under nitrogen atmosphere. Solvent was evaporated, the remaining was dissolved in CH 2 Cl 2 (100 mL). The organic solution was washed with saturated NaHCO 3 , and dried over Na 2 SO 4 . Crude oil was purified by flash chromatography (CH 2 Cl 2 —MeOH/95:5) to give white solid, 0.31 g (83%). This solid free base was treated with HCl in ether to give off-white solid 0.3 g as HCl salt, mp 154° C. (dec.).
[0131] {3-(3,4-Dichlorophenyl)-3-[3-(4-hydroxy-4-phenyl-piperidin-1-yl)-propyl]-piperidin-1-yl}-phenyl-methanone Monohydrochloride (20-2)
[0132] This compound was prepared in the same manner for the title compound (20-1), except that compound (B-1) was replaced with compound (B-2), 99% yield, mp 136-140° C.
[0133] {3-(3,4-Dichlorophenyl)-3-[3-(4-phenyl-piperidin-1-yl)-propyl]-piperidin-1-yl}-phenyl-methanone Monohydrochloride (20-3)
[0134] This compound was prepared in the same manner for the title compound (20-1), except that compound (B-1) was replaced with compound (B-3), 94% yield, mp 136-138° C.
[0135] 4-Benzensulfonylmethyl-4-hydroxy-piperidine TFA (B-1)
[0136] Diisopropylethylamine (28.3 mL, 162.75 mmol) and di-t-butyl dicarbonate (28.4 g, 130.02 mmol) were added in sequence to a mixture of piperidone hydrate hydrochloride (12) (10.0 g, 65.1 mmol) in methanol (50 mL). The mixture was stirred at room temperature for 20 hours. The solvent was removed, and the remaining was partitioned in ether and 1 M KHSO 4 solution. The organic layer was washed with brine and saturated NaHCO 3 . The n-BuLi product was purified by flash chromatography to give a white solid (13) (12.0 g, 93%). n-BuLi (6.3 mL, 10.05 mmol, 1.6 M solution in hexane) was added to a solution of methylphenylsulfone (1.6 g, 10.0 mol) in THF (33 mL) at −40° C. After stirring at this temperature for 30 minutes, a solution of N-BOC-piperidone (13)(2.2 g, 11.0 mmol) in dry THF (20 mL) was added to the mixture, stirred at −40° C. for an additional hour and room temperature for another 2 hours. The reaction was worked up and the product was isolated by chromatography (CH 2 Cl 2 —MeOH/96.4) to give a solid (14) (3.3 g, 92%). Compound (14) was treated with 5 mL of 50% TFA in dichloromethane for 15 minutes: after the solvent was removed, the pure target compound weight 0.95 g (92%), mp 170-171° C.
[0137] 4-Phenyl Piperidine HCl (B-3)
[0138] A mixture of 4-hydroxy-4-phenylpiperidine (B-2) (39.7 g, 0.224 mol) and Pd/C (4.0 g) and concentrated HCl (20 mL) was subjected to hydrogenation H 2 (50 psi) for 20 hours at 40° C. The solid was filtered through celite, and the filtrate was concentrated. A white solid was obtained by recrystallizaiton from ethanol-ether (36.3 g, 82%), mp 170-173° C.
[0139] The following were prepared by the methods described above:
[0140] (R)-{3-(3,4-Dichloro-phenyl)-3-[3-(4-phenyl-piperidin-1-yl)-propyl]-piperidin-1-yl}-phenyl-methanone monohydrochloride;
[0141] (S)-{3-(3,4-Dichloro-phenyl)-3-[3-(4-hydroxy-4-phenyl-piperidin-1-yl)-propyl]-piperidin-1-yl}-phenyl-methanone monohydrochloride;
[0142] (S)-[3-[3-(4-Benzenesulfonylmethyl-4-hydroxy-piperidin-1-yl)-propyl]-3-(3,4-dichloro-phenyl)-piperidin-1-yl]-phenyl-methanone monohydrochloride;
[0143] (R)-{3-(3,4-Dichloro-phenyl)-3-[3-(4-hydroxy-4-phenyl-piperidin-1-yl)-propyl]-piperidin-1-yl}-naphthalene-2-yl-methanone;
[0144] (R)-{3-(3,4-Dichloro-phenyl)-3-[3-(4-hydroxy-4-phenyl-piperidin-1-yl)-propyl]-piperidin-1-yl}-pyridin-4-yl-methanone;
[0145] N-(1-{3-[3-(3,4-Dichloro-phenyl)-1-(1H-imidazole-2-carbonyl)-piperidin-3-yl]-propyl}-4-phenyl-piperidin-4-yl)-acetamide;
[0146] (R)-{3-(3,4-Dichloro-phenyl)-3-[3-(4-hydroxy-4-phenyl-piperidin-1-yl)-propyl]-piperidin-1-yl}-phenyl-methanone;
[0147] (R)-{3-(3,4-Dichloro-phenyl)-3-[3-(4-phenyl-piperidin-1-yl)-propyl]-piperidin-1-yl}-phenyl-methanone;
[0148] (3-(3,4-Dichloro-phenyl)-3-{3-[4-(4-fluoro-phenyl)-4-hydroxy-piperidin-1-yl]-propyl}-piperidin-1-yl)-phenyl-methanone;
[0149] [3-[3-( 4 -Benzenesulfonylmethyl-4-hydroxy-piperidin-1-yl)propyl]-3-(3,4-dichloro-phenyl)-piperidin-1-yl]-phenyl-methanone;
[0150] {3-(4-Fluoro-phenyl)-3-[3-(4-hydroxy-4-phenyl-piperidin-1-yl)-propyl]-piperidin-1-yl}-phenyl-methanone;
[0151] {3-(3,4-Dimethoxy-phenyl)-3-[3-(4-hydroxy-4-phenyl-piperidin-1-yl)-propyl]-piperidin-1-yl}-phenyl-methanone;
[0152] {3-(3,4-Dimethyl-phenyl)-3-[3-(4-hydroxy-4-phenyl-piperidin-1-yl)-propyl]-piperidin-1-yl}-phenyl-methanone;
[0153] [3-[3-( 4 -Hydroxy-4-phenyl-piperidin-1-yl)-propyl]-3-(3,4,5-trichloro-phenyl)-piperidin-1-yl]-phenyl-methanone;
[0154] {3-(3,4-Dichloro-phenyl)-3-[4-(4-hydroxy-4-phenyl-piperidin-1-yl)-butyl]-piperidin-1-yl}-phenyl-methanone; and
[0155] {3-(3,4-Dichloro-phenyl)-3-[6-(4-hydroxy-4-phenyl-piperidin-1-yl)-hexyl]-piperidin-1-yl}-phenyl-methanone. | The small nonpeptides of the instant invention are tachykinin antagonists. The compounds are highly selective and functional NK 3 antagonists expected to be useful in the treatment of pain, depression, anxiety, panic, schizophrenia, neuralgia, addiction disorders, inflammatory diseases, gastrointestinal disorders, vascular disorders, and neuropathological disorders. | 2 |
TECHNICAL FIELD
This invention relates to the field of manually-operated pumping dispensers having particular utility for viscous products such as toothpaste and the like.
BACKGROUND
Prior co-pending applications Ser. No. 06/565,540, filed Dec. 27, 1983, and Ser. No. 06/589,640 filed Mar. 14, 1984, both assigned to the assignee herein, disclose a viscous product dispenser utilizing a free-floating take-up piston which automatically responds to the discharge of a volume of product from the dispenser by moving under the influence of atmospheric pressure to "take up" the space in the chamber left vacant by the discharged product. It has been found that in isolated circumstances during shipment or other handling of the dispenser, a sharp blow to the dispenser may result in the take-up piston inching forwardly in the product chamber by a small increment, notwithstanding the fact that the actuating lever has not been depressed. Because the take-up piston is provided with one-way retaining structure which prevents it from moving in a reverse direction, once the takeup piston has been jarred forwardly, it applies an additional loading pressure to the contents and encourages at least a minimal amount of seepage from the discharge spout of the dispenser. This can occur to a certain extent even though the actuating lever as disclosed in such prior applications is provided with a shutoff valve flap integral therewith that covers the outlet of the spout during periods of nonuse.
Another prior co-pending application Ser. No. 06/653,297, filed Sept. 24, 1984, also assigned to the assignee herein discloses and claims a removable shipping seal in the form of a tape or the like which covers the discharge spout of the dispenser and guards against seepage in that manner. Prior to first actuation of the device, the tape is simply pulled from the spout and discarded.
SUMMARY OF THE PRESENT INVENTION
An important object of the present invention is to provide an alternative to the aforementioned sealing tape concepts in the form of locking means associated with the take-up piston itself and which is operable when locked to prevent the takeup piston from moving toward the opposite end of the dispenser in a way which would tend to pressurize the contents. At the time of first actuation of the dispenser, the locking means is released, permitting the piston to perform in the usual way.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a vertical cross-sectional view of a viscous product dispenser utilizing one form of take-up piston locking means constructed in accordance with the principles of the present invention;
FIG. 2 is a transverse cross-sectional view thereof taken substantially along line 2--2 of FIG. 1;
FIG. 3 is a fragmentary, vertical crosssectional view of the dispenser utilizing a second form of take-up piston locking means;
FIG. 4 is a transverse cross-sectional view thereof taken substantially along line 4--4 of FIG. 3;
FIG. 5 is a fragmentary vertical cross-sectional view of the dispenser illustrating a third form of take-up piston locking means constructed in accordance with the principles of the present invention;
FIG. 6 is a fragmentary transverse cross-sectional view thereof illustrating details of construction;
FIG. 7 is a fragmentary vertical cross-sectional view of the dispenser illustrating a fourth embodiment of take-up piston locking means constructed in accordance with the principles of the present invention;
FIG. 8 is a fragmentary top plan view of the cover plate and integral, tear-away locking strip removed from the dispenser in order to reveal details of construction;
FIG. 9 is a fragmentary vertical cross-sectional view of the dispenser illustrating a fifth form of locking means wherein the piston must override an impediment built into the interior wall surface of the dispenser body; and
FIG. 10 is a fragmentary vertical crosssectional view of the dispenser showing a sixth embodiment of the locking means in accordance with the present invention wherein the anti-retrograde structure of the floating piston is maintained in a disabled condition prior to initial, intential movement thereof.
DETAILED DESCRIPTION
The dispenser 10 of FIG. 1 includes a tubular, cylindrical body 12 provided with a normally lower end 14 and a normally upper end 16. Adjacent the upper end 16, the body 12 is provided with a pumping piston 18 which may be reciprocated through an actuating lever 20 by depressing and releasing the latter. A coil spring 22 yieldably biases the piston 18 toward its unactuated position as illustrated in FIG. 1, and a discharge spout 24 is secured to the upper tubular shank 26 of piston 18 for guiding product out of a passage 28 defined by the internal configuration of the spout 24 and the shank 26 of piston 18. A valve flap 30 integral with and forming a part of the actuating lever 20 is operable to close off the outermost extremity of the spout 24 when the dispenser 10 is in a standby condition awaiting the next actuation.
A floating take-up piston 32 is housed within the body 12 adjacent the lower end 14 thereof and makes sealing engagement with the interior wall surface of the body 12 via a pair of upper and lower, outwardly flaring skirts 34 and 36. A downwardly and outwardly flaring resilient metal skirt 38 or the like also bears against the inner wall surface of the body 12 and is sufficiently resilient that it will deflect downwardly to any extent necessary to permit the piston 32 to rise in the body 12 yet at the same time is sufficiently stiff as to bite into the wall surface during attempted retrograde movement of the piston 32 downwardly within the body 12. A cover plate 40 of circular configuration is secured to the underside of the piston 32 in covering relationship to the metal skirt 38 so as to protectively shield the latter.
In accordance with the principles of the present invention, the dispenser 10 is provided with locking means broadly denoted by the numeral 42 for releasably retaining the take-up piston 32 against unintentional movement upwardly within the body 12. In the embodiment illustrated in FIGS. 1 and 2, such locking means 42 includes a pair of diametrically opposed and partially circumferentially extending, integrally formed shoulders 44 on the interior wall surface of the body 12 adjacent lower end 14, as well as cooperating peripheral edge portions 46 of the cover plate 40 which underlie the shoulders 44 when locking means 42 is locked and serve as abutments bearing against shoulders 44. The cover plate 40 is also provided with a pair of diametrically opposed, peripheral notch portions 48 corresponding in shape to the shoulders 44 and adapted to clear the latter when notches 48 are aligned with shoulders 44.
The cover plate 40 is rotatable relative to the body 12 between a locking position in which the edge abutment portions 46 underlie the shoulders 44 (as shown in FIGS. 1 and 2) and a releasing position in which the notches 48 underlie and are aligned with the shoulders 44. In this respect, in its preferred form, the cover plate 40 is provided with an upwardly projecting stud 50 that is pressed securely into a receiving socket 52 in the piston 32 such that the cover plate 40 is not only securely attached to the piston 32 but is also normally prevented from rotation relative to the latter. Consequently, rotation of the cover plate 40 for releasing the locking means 42 also causes rotation of the piston 32, but such is of no consequence. A depending, finger-graspable blade 54 on the bottom of the cover plate 40 facilitates manual rotation of the latter.
When the dispenser 10 is first assembled and filled with product, the cover plate 40 is positioned as illustrated in FIGS. 1 and 2 such that the piston 32 is firmly locked in place. Any jarring or other vibrational impacts to the dispenser 10 during shipment and subsequent storage will have no effect upon the piston 32, and thus the product contained within the body 12 will have no particular tendency to attempt to exude from the spout 24. When it is desired to dispense product for the first time, the cover plate 40 is simply grasped by the blade 54 and rotated into such a position that the notches 48 are aligned with the shoulders 44. Thereupon, actuation of the lever 20 will cause the pumping piston 18 to be depressed, and because the metal skirt 38 prevents retrograde movement of the piston 32, such depression of the pumping piston 18 will cause product to be forced up and out of the passage 28. As is apparent, by actuating the lever 20, the valve flap 30 is likewise actuated to uncover the spout 24.
When the lever 20 is then released, the return spring 22 causes the pumping piston 18 to return to its normal raised position. Due to closing of the valve flap 30 and also due to the viscous nature of the product remaining within the passage 28, lifting of the piston 18 results in the creation of a negative pressure within the pumping chamber 56 between pistons 18 and 32. Inasmuch as the lower end of the take-up piston 32 is open to the atmosphere via the notches 48 in cover plate 40, as well as other clearances between the cover plate 40 and the interior wall surface of the body 12, the take-up piston 32 is caused to rise in the chamber 56 and ultimately decrease the volume thereof by an amount corresponding to the volume of the vacated product. The cover plate 40 travels along with the piston 32 during such take-up movement.
EMBODIMENT OF FIGS. 3 AND 4
The dispenser 110 of FIGS. 3 and 4 functions to dispense product in the same manner as the dispenser 10. So also do the dispensers of the remaining embodiments which will be subsequently described. In each case, it is the locking means for the take-up piston which varies, and therefore only details of the locking means for each embodiment will be hereinafter elaborated upon.
In the dispenser 110 and the stud 150 on cover plate 140 is rotatably received within socket 152 in piston 132, rather than being tightly pressed therein as in the first embodiment. The locking means 142 includes, as one of its interengageable parts, a pair of diametrically opposed shoulders 144 on the stud 150. Co-acting with the shoulders 144, and forming another part of the locking means 142, is a pair of diametrically opposed abutments 146 at the lower end of the socket 152. The abutments 146 project radially inwardly into the interior of the socket 152 and underlie the radially outwardly projecting shoulders 144 when locking means 142 is locked as illustrated in FIGS. 3 and 4, but when the cover plate 140 is rotated 90 degrees from the illlustrated position, shoulders 144 move into alignment with spaces between the abutments 146 whereby to clear the latter and permit upward travel of the piston 132.
The cover plate 140 has its outermost circular periphery snapped into a retaining groove 158 in the body 112 so that, while cover plate 140 may be rotated between its locking and unlocking positions utilizing the depending blade 154, the cover plate 140 cannot move axially of the body 112. Thus, once the piston 132 is released by appropriate positioning of the shoulders 144, the piston 132 rises in the body 112 without the cover plate 140 which remains behind in its retaining groove 158.
The cover plate 140 is provided with a small aperture 160 which exposes the bottom of the piston 132 to atmospheric pressure.
EMBODIMENT OF FIGS. 5 AND 6
The dispenser 210 is provided with locking means 242 which includes in part an opening or slot 262 in the sidewall of body 212, the upper extremity of the slot 262 serving as a limiting shoulder 244. An abutment 246 on the cover plate 240 is in the form of a radially projecting break tab which projects through the slot 262 and normally bears against the shoulder 244 when the locking means 242 is locked. A line of weakness 246a connects the abutment break tab 246 with the cover plate 240, and while such line of weakness 246a is sufficiently strong as to normally remain intact and prevent the piston 232 from rising in the body 212 during jostling and jarring, it is at the same time sufficiently weak and brittle as to permit severance of the tab 246 from the cover 240 when the tab 246 is manually worked up and down a few times to overstress the line of weakness 246a.
Once the tab 246 has been broken from the cover plate 240, the piston 232 and cover plate 240 are free to rise together in the body 212 under the influence of atmospheric pressure bearing against the cover plate 240.
EMBODIMENT OF FIGS. 7 AND 8
The dispenser 310 has locking means 342 wherein the shoulder 344 on the body 312 is in the nature of a downwardly projecting rim adjacent the lower end 314 of the body 312. The abutment 346 of the locking means 342 is in the nature of a tear strip which is integrally molded with the cover plate 340 at the outer circumferential edge thereof. The tear strip 346 overlaps the annular shoulder or rim 344 and complementally receives the latter, and there is a circumferential line of weakness 346a joining the tear strip 346 with the cover plate 340. Although the line of weakness 346a is adequately strong as to normally resist fracture and hold the piston 322 in place, by the same token it is sufficiently weak as to be torn from the cover 340 when a pull tab 346b of the strip 346 is gripped and pulled in a circumferential direction about the cover 340 so as to separate the strip 346 from the latter.
Once the strip 346 has been separated from the cover plate 340, the latter and the piston 332 are free to rise together in the body 312 under the influence of atmospheric pressure bearing against the underside of the plate 340. It will be noted that the strip 346 has a slight transverse cut 346c therein closely adjacent the pull tab 346b so as to facilitate the stripping separation of strip 346 from the cover plate 340.
EMBODIMENT OF FIG. 9
The dispenser 410 in FIG. 9 is provided with locking means 442 wherein the shoulder 444 comprises an annular step-like structure formed at the intersection of an enlarged diameter portion 412a of the body 412 and the normal diameter portion 412b of the body 412. The abutment 446 of the locking means 442 comprises the upper and outermost extremity of the upper outwardly flaring skirt 434 on the piston 432. As will be apparent, when initially installed the piston 432 is disposed within the enlarged diameter portion 412a of the body 412 with the upper skirt 446 bearing against the step shoulder 444. Preferably, the step shoulder 444 is beveled or inclined upwardly and inwardly in the nature of a ramp, rather than comprising an abrupt impediment or stop disposed in perpendicular relationship to the direction of axial travel of the piston 432. Consequently, while the step shoulder 444 provides adequate resistance to upward movement of the piston 432 as a result of jarring or jostling of the dispenser 412, such resistance is inadequate to retain the piston 432 in place when either a negative pressure condition exists within the body 412 after dispensing a quantity of product upon first actuation, or when the piston 432 is manually pushed upwardly a sufficient distance to cause the skirt 434 to override the step shoulder 444.
EMBODIMENT OF FIG. 10
The dispenser 510 in FIG. 10 has locking means 542 wherein the shoulder 544 is defined by the upper extrimity of an annular groove within the interior wall surface of the body 512 adjacent the lower end thereof. The abutment 546 of locking means 542 comprises the outermost end portion of the anti-retrograde metal skirt 538 associated with the piston 532. If desired, the groove 544 may rather closely confine the skirt 538 whereas to prevent all upward movement of the piston 532 except under the influence of strong forces such as occurring upon actuation of the dispenser 512 or manual pressure against the bottom of cover plate 530. Preferably, however, the groove 544 is sufficiently deep that the skirt 538 is not enabled to bottom out within the groove 544 and make biting contact therein. Furthermore, the groove 544 is preferably sufficiently wide as to thus receive the skirt 538 in what may be thought of as a free, unstressed state. Thus, in the event that the piston 532 should tend to be jostled upwardly, the skirt 538 remains within the confines of the groove 544 and the piston 532 is free to return to its initial position since the skirt 538 has not made biting, anti-retrograde engagement with the body 512.
It should be apparent that all of the foregoing embodiments of the locking means for the floating piston of the dispenser achieve the objective of preventing undue pressurization of the contents of the dispenser by the take-up piston in the event that rough handling is encountered. Yet, each of the disclosed embodiments may be easily released or overridden at the time of first actuation of the dispenser in order to prepare the take-up piston for performing its intended function. | The atmospheric pressure-operated take-up piston of the dispenser is provided with releasable locking structure which retains the piston prior to first intentional actuation of the dispenser against jarring movements tending to pressurize the contents and promote leakage during shipment and storage. Once the piston has been intentionally unlocked from its starting position at one end of the dispenser, it is free to travel under the influence of atmospheric pressure to take up space left vacant by discharged product. Several different forms of structure means for the take-up piston are disclosed. | 0 |
BACKGROUND OF THE INVENTION
The present invention relates to the use of a temporary or fugitive alloying element to promote a phase transformation in a metal. Hydrogen is of particular interest, particularly with respect to titanium alloys, because it has significant effects on some metal systems and may be removed from the metal after treatment.
Hydrogen has been previously used to modify the properties of titanium and its alloys. It has been used to embrittle titanium to facilitate its comminution by mechanical means to form titanium metal powders. In such techniques hydrogen is diffused into the titanium at elevated temperatures, the metal is cooled and brittle titanium hydride formed. The brittle material is then fractured to form a powder. The powder may then have the hydrogen removed or a compact may be formed of the hydrided material which is then dehydrided, U.S. Pat. No. 4,219,357 to Yolton et al.
Hydrogen also has the effect of increasing the high temperature ductility of titanium alloys. This characteristic has been used to facilitate the hot working of titanium alloys. Hydrogen is introduced to the alloy which is then subjected to high temperature forming techniques such as forging. The presence of hydrogen allows significantly more deformation of the metal without cracking or other detrimental effects, U.S. Pat. No. 2,892,742 to Zwicker et al.
Hydrogen has also been used as a temporary alloying element in an attempt to alter the microstructure and properties of titanium alloys. In such applications, hydrogen is diffused into the titanium alloys, the alloys cooled to room temperatures and then heated to remove the hydrogen. The effect of the temperature of introducing and removing the hydrogen on the structure and properties of titanium alloys was investigated W. R. Kerr et al. "Hydrogen as an Alloying Element in Titanium (Hydrovac)," Titanium '80 Science and Technology (1980) p. 2477.
The present invention is directed to the treatment of metal castings subsequent to the casting operation. It is particularly concerned with metal castings using metals or alloys which undergo a solid state allotropic transformation on cooling from elevated temperature, particularly the Group IVB elements and their alloys, including titanium.
In the production of Group IVB element alloy castings such as titanium, it is well known that certain structural imperfections may limit the suitability of the material for its intended applications. This is particularly important in highly stressed, critical applications such as gas turbine engine and other heat engine components, airframe, space vehicle and missile components, and orthopedic implant devices, such as hip joints and knee protheses. These limitations have become increasingly important in recent years because precision castings are being specified more frequently for critical applications because of their intrinsic cost advantage compared to competitive methods of manufacture.
Voids are one general type of imperfection which can exist in Group IVB element castings as a result of microshrinkage, cavity shrinkage, and other effects resulting from solidification. It is well known to those skilled in the art that this type of imperfection can be eliminated by hot isostatic pressing (HIP).
Another type of imperfection which has traditionally limited the utility of Group IVB element castings is unsatisfactory chemical compositional control in surface regions that are in contact with the mold material during solidification. Because of the relatively high chemical reactivity of Group IVB alloys, surface imperfections such as oxygen enrichment, contamination, and alloy depletion effects may be encountered. Within recent years, methods to circumvent this type of difficulty have become generally known. The techniques include the use of more refractory mold materials to limit the extent of surface interaction, and the use of specialized chemical milling treatments to remove desired amounts of surface material in a reproducible manner after casting, and thereby achieve dimensional accuracy in the final part.
A third type of limitation of Group IVB element castings arises because of the influence of the material's allotropic transformation on the casting's solidification history. This results in a microstructure which is coarser than that achieved with deformation processing operations such as forging. Coarse microstructures, in turn, usually are associated with reduced dynamic low temperature properties such as fatigue strength.
With reference to FIGS. 1 and 2, the microstructural coarsening in an unalloyed Group IVB metal (FIG. 1) or a Group IVB based alloy such as Ti-6Al-4V (FIG. 2) arises in the following way. On cooling from the liquid, the material solidifies to form a solid of the high temperature body center cubic (BCC) allotrope, which is referred to herein as beta. On further cooling in the mold, the material reaches the beta transformation (beta transus) temperature (T T in FIG. 1) where all or part of the beta transforms to the low temperature, hexagonal close packed (HCP) allotrope, which is referred to herein as alpha. In the case of the pure metal (FIG. 1), the as-cast microstructure consists entirely of alpha ("transformed beta") platelets, the orientation of which relate to certain crystallographic planes of the prior beta phase, and the size of which relates to both the cooling time through the transformation temperature and the subsequent cooling rate. In the case of an alloy such as Ti-6Al-4V, (FIG. 2) the material exhibits a coarse two phase microstructure of alpha ("transformed beta") plus beta, because the example alloy contains sufficient alloying element content to stabilize some fraction of the beta to room temperature. In either case, the alpha which has formed is a relatively coarse transformation product of the high temperature beta phase, (hereafter "transformed beta") and it is the coarseness of the alpha which generally limits the mechanical properties of the material, particularly the low temperature dynamic properties such as fatigue strength.
Broadly speaking, there are two conventional ways to address the problem of microstructure coarseness. One is to subject the material to a deformation processing operation such as forging to "break down" and refine the structure. This method has the further advantage that an equiaxed so-called "primary alpha" phase, which traditionally has been unobtainable in a cast structure, can be formed during deformation processing, thereby permitting the achievement of microstructures which are particularly desirable for fatigue limited applications. Unfortunately, forging is an energy, capital and raw material intensive operation. In addition, it is not readily applicable to components designed to be produced as cast net shapes.
A second approach is to heat treat castings above the beta transus temperature (e.g., at temperature T 1 in FIGS. 1 and 2) to "solution treat" the material and return it to an all beta structure, and then to cool the article at a relatively rapid rate using either a stream of inert gas or a hyperbaric inert gas chamber. Optionally, this may be followed with one or more intermediate temperature aging treatments. Relatively fine microstructures can be obtained in this way because it is possible to obtain faster cooling rates using an appropriately designed heat treatment furnace than is generally achievable within the mold during and after solidification of the casting.
It is known that both of these approaches may be used to improve the properties of cast materials. As indicated above, castings are characterized by a coarse alpha (transformed beta) microstructure which, except for certain specialized applications, is generally improved by such treatments. Except for certain specialized (e.g., creep limited) applications, thermal treatment above the beta transus temperature is not generally applicable to wrought Group IVB alloys such as titanium alloys because it tends to eliminate the fatigue resistant, recrystallized "primary alpha" microstructure formed during deformation processing and return the material to a transformed beta microstructure.
Unfortunately, heat treatment of Group IVB alloy castings above the beta transus temperature has certain limitations:
(1) There is a tendency to induce beta grain growth which has the undesirable effect of increasing the grain size of the material.
(2) The use of relatively high processing temperatures, which must be performed in a vacuum or inert gas environment, subjects the material to an increased risk of interstitial surface contamination. The extent of this risk tends to increase with increased solutioning temperature.
(3) Due to simple heat transfer considerations, there are section size limitations on the ability to achieve a rapid cooling rate.
(4) The use of rapid cooling rates subjects the material to significant dimensional changes and the risk of distortion and cracking.
The present invention relates to the use of a "catalytic" or "fugitive" solute to induce a phase transformation in a metal and in that manner refine the microstructure without the complications of forging or the limitations of conventional heat treatments. As will be set out in greater detail in following portions of the specification, the solute that has the effect of lowering a transformation temperature is diffused into the metal when it is below a transformation temperature. The presence of the solute causes the transformation and the removal of the solute reverses the transformation.
By example, a removable solute, such as hydrogen, may be used as a temporary alloying element in Group IVB metals and their alloys as a means to promote the alpha to beta or the alpha plus beta to beta phase transformation, and the reverse reactions, under controlled conditions. In this manner microstructural refinement can be obtained under substantially isothermal processing conditions, at temperatures which are significantly below those required for traditional solution treatment and quenching operations.
Such a process is schematically illustrated in FIG. 3 which shows the effect of a solute element which stabilizes the high temperature beta allotrope to lower temperatures. In its simplest form: (1) the material is heated to temperature T 2 , which can be several hundred degrees below T T and T 1 ; (2) the solute is introduced into the material such that the composition moves along line OP of FIG. 3, thereby isothermally solution treating it into the beta phase field; (3) the solute is rapidly removed from the material (reversibly along line PO, for example), to isothermally "quench" the material; and (4) the material is cooled to room temperature using conventional means.
SUMMARY OF THE INVENTION
The present invention overcomes the problems and disadvantages of the prior art by providing a means for refining the microstructure of a metal casting where the metal has an elevated transformation temperature at which a first phase in the metal transforms to a second phase. The metal casting is heated to a treatment temperature near but below the transformation temperature. A solute material, having a physical effect such that it reduces the transformation temperature, is then diffused into the metal casting. The solute is diffused into the metal casting in a concentration such that it reduces the transformation temperature to at least that of the treatment temperature thereby inducing the transformation of the first phase of the metal into the second phase. The solute is then removed from the metal casting by diffusion at a rate sufficient to transform the second phase of the metal back to the first phase which has the result of refining the microstructure of the first phase when it is reformed. The solute is removed at a temperature above that at which it would form undesirable or detrimental compounds in the metal. Preferably, the metal is one from Group IVB of the Periodic Table, i.e., titanium, zirconium and hafnium.
The present invention finds particular utility in the treatment of titanium castings which comprise a mixture of hexagonal close-pack alpha and body-centered cubic beta, with all or a portion of the alpha having been formed from the beta phase. The microstructure of this portion of the alpha is refined by subsequently transforming the portion to beta by the diffusion of a material into the metal casting and thereafter diffusing out the material to induce an accelerated transformation of beta to alpha in this portion of the metal.
Preferably, the solute material diffused into the metal to induce the transformations is hydrogen.
The accompanying drawings and photomicrographs, which are incorporated in and constitute a part of this specification, illustrate the principles of the invention and its embodiments.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic representation of the allotropic transformation of a metal as a function of temperature.
FIG. 2 is a schematic representation of a metal alloy depicting the phases presents as a function of temperature.
FIG. 3 is a phase diagram illustrating the relationship between the phases of a metal alloy with the increasing concentration of a removable solute dissolved therein.
FIG. 4 is a photomicrograph of Ti-6Al-4V metal alloy in the as-cast condition at 200X.
FIG. 5 is a photomicrograph of the same material of FIG. 4 after treatment by means of the present invention as described in Example 1.
FIG. 6 is a photomicrograph of cast Ti-6Al-4V metal alloy which has received a hot isostatic pressure treatment at 1650° F.
FIG. 7 is a alloy of FIG. 6 after a treatment by the method of the present invention at a constitutional quenching rate of 0.13% per hour, as described in Example 2.
FIG. 8 is the same material as shown in FIGS. 6 and 7; however, this material has been treated by means of the present invention at a constitutional quenching rate of 0.32% per hour, as described in Example 2.
FIG. 9 is an enlarged (2.5×) photograph of a cast and electro-chemically machined gas turbine compressor blade of Ti-6Al-4V, as treated by the present invention as described in Example 3.
FIG. 10 is the same article as that shown in FIG. 9, except it was treated by the conventional hydride-dehydride process also described in Example 3.
FIG. 11 is a photomicrograph of a cast Ti-6Al-4V alloy that has received a hot isostatic pressing at 1650° F. as described in Example 4.
FIG. 12 is the same material as FIG. 11 after having received treatment by the present invention, as described in Example 4.
FIG. 13 is a graphic representation of the fatigue properties of conventionally treated materials compared to those treated by the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
As noted above, the method of the present invention involves the diffusion of a solute material into a metal in order to promote a transformation in the metal. Subsequent removal of the solute results in the reversal of the transformation at a rate that beneficially affects the microstructure of the metal.
The method of the present invention finds particular utility in treating titanium alloys with hydrogen although the invention should be operable with other metal alloys and by diffusion of materials other than hydrogen.
On cooling from elevated temperature titanium and its alloys undergo an allotropic transformation from the body-centered-cubic (BCC) beta form to the hexagonal-close-packed (HCP) alpha form. The temperature of this transformation is affected by the presence of other elements and of those hydrogen has the advantage of being easily removed from the metal. Other metals that undergo allotropic transformations could also be treated in such a manner including the other Group IVB elements Zr and Hf. Other elements such as lithium and sodium or the lanthanide series (atomic numbers 58 through 73) may also be operable with the present invention. In particular, neodymium, holmium and praseodynium, which undergo a beta (BCC) to alpha (HCP) transformation would appear to be operable with the present invention.
The material that induces the transformation in the metal is referred to herein as the solute or the catalytic solute as it does not appear to take part in the transformation reaction and is contained in the final product only in trace amounts. While the exact mechanism by which the catalytic solute affects the transformation and hence the process embodiments of the invention is not completely understood, certain parameters concerning its behavior have been determined from a study of the use of hydrogen as the catalytic solute in titanium alloys. In general, it appears that the catalytic solute should reduce the temperature at which a high temperature phase is stable and in addition not react irreversibly with constituents to form compounds detrimental to the metal at the treatment temperatures.
To facilitate the process embodiments of the invention, the catalytic solute should be easily handled in an industrial environment. In addition, it should be sufficiently mobile at the processing temperature, such that it may be introduced and removed within time periods of practical interest. The actual extent of removal times, and the practicality thereof, will be a function of section size involved. For example, thin metallic coatings or the outer layers of composite laminates may be effectively treated in accordance with the invention within times of practical interest using a relatively slow moving catalytic solute species that would be unsuitable for treatment of a thicker section.
Although the present invention is primarily concerned with refining the microstructure throughout the entire cross section of cast components, and the ability to treat heavy sections is demonstrated by a later example, the technique may also be used as a means to modify the surfaces of castings. Where hydrogen is used as the catalytic solute, limiting the hydrogen partial pressure, or controlling the hydrogenation time at a given pressure, may be used to limit the catalytic solute addition to only the surface regions of a casting. After solute removal, the microstructural refinement and property modification would be restricted to surface regions, the depth of which would be determined by the hydrogenation process parameters that were employed.
In the treatment of reactive metals, the surface cleanliness of the material to be treated and the purity of the inert atmosphere under which it is processed must be carefully controlled. Surface contamination of reactive metal castings, such as by oxygen in the case of titanium, is not only deleterious to the article, but can result in a surface diffusion barrier which limits the rate at which a catalytic solute such as hydrogen can be introduced into and removed from the articles being treated.
In addition, care must be taken during practice of the invention to use proper combinations of temperature and composition to insure that undesirable intermediate phases are not formed in the material. Intermediate phases are often brittle and, by nature of their atomic volume differences with the base metal, can produce significant distortion and/or cracking of precision shaped components. For example, the formation of titanium hydride should be avoided when treating titanium alloys by hydrogenating and dehydrogenation. This is accomplished by maintaining the temperature of the metal above that at which detrimental compounds are formed throughout the process steps where the solute is present.
In principle, a variety of low atomic number (e.g., less than about 16), and thus relatively mobile species might be used as the catalytic solute. Based on the considerations given above, however, hydrogen appears to be a particularly desirable catalytic solute especially for use with Group IVB elements and their alloys. Hydrogen increases the stability of the allotropic BCC phase relative to low temperature HCP phase since it is more soluble in the "relatively open" BCC structure. In addition, the element is a gas which can be easily handled using more or less conventional pumping systems, it exhibits a very high mobility (diffusion rate) in alloys of engineering interest, and the compounds it forms with Group IVB elements are relatively unstable. Titanium hydride, for example, appears to be stable only at temperatures below 1184° F. in the binary Ti-H system.
The temperature at which the catalytic solute should be added to the metal depends primarily on the degree by which the temperature of the desired transformation can be affected by the catalytic solute. Where small concentrations of catalytic solute are able to reduce the transformation temperature significantly there may be no need to heat the metal to a temperature close to its normal transformation temperature. The relationship between the composition of the metal being treated, the composition of the catalytic solute and the temperature at which the diffusion of the catalytic solute takes place has not been determined for all materials that would be operable with the present invention. One skilled in the art, however, may readily determine such relationships in light of the parameters applicable to titanium alloys set out herein.
For titanium alloys, the treatment temperature may be in the range of from 800° F. to 2000° F. and preferably in the range of 1200° F. to 1600° F. For the Ti-6Al-4V alloy, the preferred solute introduction temperature is in the range of from 1200° F. to 1550° F.
The level of catalytic solute addition is, as noted above, related to other factors and can readily be determined in light of the teachings of the present specification. For titanium metal and its alloys, the catalytic solute concentration where the catalytic solute is hydrogen may be in the range of from 0.2% to 5% by weight. Preferably, the range is 0.5% to 1.1% and for Ti-6Al-4V alloys it is preferred to be in the range of from 0.6% to 1.0%.
Although the effect of the partial pressure of the gaseous catalytic solute has not been completely determined and the examples given herein relate to charging hydrogen (hydrogenating) at partial pressures of up to 1.1 atmosphere (836 mm of mercury), charging the solute under hyperbaric conditions (e.g., 10 or even 1,000 atmospheres, as in a HIP unit), may be used as a means to accelerate the introduction of the solute at a given section size or to permit the introduction of greater amounts of catalytic solute at a given temperature.
The catalytic solute must in most systems be removed both in order to reverse the solute induced transformation and to eliminate detrimental effects of the solute on the properties of the metal. For titanium based materials using a hydrogen solute the rate of solute removal may be in excess of 0.01% per hour and preferably in excess of 0.1% per hour. For the Ti-6Al-4V alloy, the rate of hydrogen removal is preferably in the range of from 0.2% to 0.5% per hour. The solute may be removed in an inert atmosphere or a vacuum.
It should be understood that the solute removal rates referred to represent average values. Instantaneous or localized removal rates may be several orders of magnitude higher than average during the initial stages of dehydrogenation, and several orders of magnitude lower than average during the final stages of solute removal.
The temperature at which the catalytic solute is removed should be high enough that diffusion of the solute is facilitated, and it should be above the temperature at which deleterious phases are stable. The presence of large amounts of residual hydrogen in Group IVB alloys such as Ti-6Al-4V must be avoided. Under normal circumstances, treatment should include sufficient time at temperatures above about 1200° F. under a vacuum level greater than about 10 -4 torr to insure removal of the hydrogen to levels below about 150 ppm. An alternative method would be to initially dehydrogenate the material to a "safe" level from the standpoint of integrity and dimensional considerations (e.g., 800 ppm) in the hydrogenating furnace and then to perform a subsequent vacuum annealing operation employing a conventional vacuum heat treatment furnace.
The present invention is disclosed using titanium and hydrogen and in most examples an isothermal process where the treatment temperature and the solute removal temperatures are approximately the same. In the disclosed embodiment using Ti-6Al-4V, it is preferred that the solute removal temperature be in the range of from 1200° F. to 1550° F.
The treatment temperatures are related to the beta transus temperature and the present invention has been successfully practiced with a number of titanium alloys. Specifically the present invention has successfully refined the microstructure of the following titanium alloys: TI-6Al-4Zr-2Mo, Ti-8Al-1V-1Mo and Ti-5Al-2.5Sn.
The use of an isothermal or near isothermal solute removal step is not necessary. An alternative procedure is set out in FIG. 3. As an alternative to the isothermal process of heating the material to temperature T 2 , charging catalyst along path OP, removing the catalyst along path PO, and cooling to room temperature, the following procedural variations may be used:
(1) To shorten the cycle time, the catalytic solute may be charged simultaneously with heating. This is schematically suggested by the path CP in FIG. 3. Removal of the catalyst solute may then occur at a temperature T 2 along path PO.
(2) Once point P has been reached, as an alternative to catalytic solute removal along path PO, the temperature could be reduced along path PQ to a temperature T 3 , and then remove solute along path QRS or QRC. This would minimize the time necessary to introduce the desired amount of solute while maximizing the degree of microstructural refinement that is obtained, because the material would be "constitutionally quenched" at a lower processing temperature. This kind of cycle has been termed "near isothermal" processing, because T 2 and T 3 are both significantly below T T and T 1 ; substantially identical phase relationships exist at T 2 and T 3 ; and the absolute difference between T 2 and T 3 is significantly less than the difference between either T 2 or T 3 and 70° F. It should be noted, however, that in a practical sense T 2 and T 3 might differ by several hundred degrees.
Operation of the invention and its variants is further illustrated by the following examples; wherein the metal used to illustrate the invention is a cast Ti-6Al-4V alloy having the following composition:
______________________________________CHEMICAL COMPOSITION OF CAST Ti-6Al-4V ALLOY AMS 4928Element Specification Example Material______________________________________Ti Bal BalAl 5.50-6.75 6.28V 3.50-4.50 4.04Fe 0.30 max. 0.21C 0.10 max. 0.02O 0.20 max. 0.20N 0.075 max. 0.009H 0.015 max. 0.0006______________________________________
EXAMPLE 1
Ti-6Al-4V, having the composition given above, was vacuum investment cast in metal oxide molds to provide 5/8 inch diameter test bars and various precision shapes having section sizes of up to 11/8 inch. The following operations then were performed: (1) the material was loaded into a hydrogen/vacuum furnace at room temperature; (2) the system was pumped down to below 10 -4 torr using standard argon backfill and repumping techniques; (3) the load was heated to approximately 1450° F. under vacuum; (4) the system was charged with pure hydrogen gas at a constant pressure of 1 psi gauge (15.7 psia) for a period of one hour to introduce approximately 0.8 percent by weight hydrogen into the material; (5) the system then was reevacuated at 1450° F. for a period of 21/2 hours first using a mechanical pump and 1300 ft 3 /min "blower" combination and then employing a 6 inch diffusion pump to obtain a vacuum of about 10 -4 torr; and (6) the load was cooled to room temperature and removed from the furnace. Metallographic examination of the subject material revealed substantial microstructural refinement compared to the as-cast starting material, as depicted in FIGS. 4 and 5.
EXAMPLE 2
The as-cast Ti-6Al-4V alloy test specimens and shapes described in Example 1 were hot isostatically pressed (HIP'ed) at 1650° F. and 15 ksi for two hours to substantially eliminate any shrinkage porosity present in the articles. The microstructure of this material is depicted in FIG. 6. The HIP'ed material then was subjected to 1450° F. isothermal treatment substantially identical to that described in Example 1, wherein hydrogen was introduced over a period of one hour to achieve about 0.8 percent by weight in the castings and the hydrogen was removed over a period of approximately 21/2 hours at 1450° F. prior to cooling to room temperature. A companion 1450° F. isothermal run also was performed in the same way, except that the hydrogen was removed over a period of six hours using a mechanical pump having only 17 ft 3 /min capacity. Since approximately 0.8 percent by weight hydrogen was charged into the samples in both cases, the evacuation times corresponded to average "constitutional quenching rates" of approximately 0.13% per hour and 0.32% per hour, respectively. Metallographic examination of the product of these runs revealed significant microstructural refinement in both cases as depicted in FIGS. 7 and 8. The degree of refinement was significantly greater using the more rapid constitutional quenching rate of 0.32% per hour, as depicted in FIG. 8.
EXAMPLE 3
Several dozen gas turbine engine compressor blades were produced by: (1) casting oversized preforms; (2) chemically milling the preforms to remove 0.020 inch of material; (3) hot isostatically pressing the milled preforms at 1650° F. and 15 ksi for two hours; and (4) electrochemically machining them to final blade dimensions. A group of these components was processed in accordance with the present invention using a 1450° F. isothermal cycle as described in Example 1, except that approximately 1.0% hydrogen was introduced into the material and the solute was removed over a period of four hours, which corresponds to an average constitutional quenching rate of approximately 0.25% per hour.
Visual examination and dimensional inspection revealed that integral, dimensionally acceptable components were present after the treatment of the present invention, see FIG. 9. In addition, metallographic examination of the components revealed a substantial degree of microstructural refinement, in general agreement with the results shown in FIG. 8 for a prior run that was conducted using similar parameters.
A second group of these components then was processing using a hydriding cycle which involved the following steps: (1) the blades were heated to 1450° F.; (2) the blades were hydrogenated at 1 psig for a period of one hour; and (3) the blades were cooled to 1000° F. under hydrogen and then cooled to 70° F. under argon. This cycle differed from the treatment of the present invention in that the hydrogen solute was not removed at elevated temperatures, but rather the components were exposed to a temperature wherein significant amounts of titanium hydride could form. Extensive cracking and distortion effects resulted from this procedure, FIG. 10. No effort was made to complete the hydride/dehydride cycle by dehydrogenating the blade, because dimensional integrity had already been lost.
EXAMPLE 4
The cast and HIP'ed Ti-6Al-4V test material described in Example 2 was: (1) loaded into a hydrogen/vacuum furnace; (2) evacuated to below 10 -4 torr; (3) heated to about 1550° F.; (4) charged with hydrogen at approximately 1 psig for a period of one hour; (5) cooled under hydrogen to a temperature of approximately 1200° F.; (6) dehydrogenated at 1200° F. over a period of two hours; and then (7) cooled to room temperature. Metallographic examination established that substantial microstructural refinement was obtained using this near isothermal process. The photomicrographs of FIGS. 11 and 12 demonstrate the results of this process. In addition, excellent integrity and dimensional retention were observed.
EXAMPLE 5
11/8 inch diameter bars of cast Ti-6Al-4V alloy were HIP'ed at 1650° F. and 15 ksi for two hours and treated according to the present invention in both an isothermal 1450° F. cycle and in a near isothermal cycle at 1550° F./1200° F. Uniform microstructural refinement was obtained throughout the entire cross section in every case. Ti-6Al-4V is not regarded as a deep hardenable alloy when conventional heat treatments are employed. Therefore, the data of this example establishes the utility of the present invention as a means to constitutionally solution treat and refine relatively heavy sections. The practical section size limitations, if any, of the present invention have not yet been established.
MECHANICAL TESTING
In order to demonstrate the benefits of the present invention, the Ti-6AL-4V alloy set out in the preceding table was tested in the following manner.
TENSILE PROPERTIES
A group of 0.250 inch diameter tensile test specimens were machined from the 5/8 inch diameter oversized test bars from the material treated in Example 2 at an average quenching rate of 0.32% per hour.
A second group of 0.250 inch diameter tensile test specimens were machined from the 1/8 inch diameter oversized test bars from the material treated in Example 4. Testing at 70° F. established that the process of the present invention produced a 10 to 13 ksi increase in ultimate strength and a 16 to 19 ksi increase in yield strength, combined with up to a 40% reduction in room temperature tensile ductility.
Another processing trial was performed using the near isothermal cycle described above (1550° F./1200° F.), without introducing any hydrogen into the system, in an effort to determine the effect, if any, of the thermal processing cycle itself. No significant effects on room temperature tensile properties were observed. In addition, metallographic examination failed to reveal any measurable microstructural refinement.
The results of the testing are illustrated below:
______________________________________70° F. PROPERTIES OF CASTAND HIP'ED Ti-6AL-4V ALLOYMaterial UTS 0.2% YS EL RACondition (1) (KSI) (KSI) (%) (%)______________________________________Control 143 124 14.3 24.4Material (2)Treated 155 137 12.6 22.3according to 158 143 11.6 16.7the invention 156 140 12.1 19.5(3)Treated 154 147 6.4 9.9according to 152 140 9.1 12.9the invention 154 142 9.7 22.1(4) 153 143 8.4 15.0Thermally 141 126 12.0 18.2Treated 136 121 9.8 19.2Only (5) 138 122 13.3 25.9 138 123 11.7 21.1______________________________________ (1) After casting and HIP at 1650° F. and 15 ksi for two hours. (2) Average of twelve tests performed for production heat acceptance and characterization purposes after 1550° F. anneal for two hours. (3) Isothermal processing at 1450° F. with an average constitutional quenching rate of 0.32% per hour, as described in Example 2. (4) Near isothermal processing at 1550° F./1200° F., as described in Example 4. (5) Near isothermal processing at 1550° F./1200° F. without introduction of any hydrogen catalyst, as described in Example 4.
As shown by the above data, the present invention materially improves the ultimate tensile strength (UTS) and the yield strength (YS). While the ductility of the alloy was reduced as measured both by the percent elongation (EL) and percent reduction in area (RA), the decrease was not such that the alloy was rendered excessively brittle.
FATIGUE PROPERTIES
Two groups of 5/8 inch diameter bars one of which had been treated in the 1450° F. isothermal run described in Example 4 using a 0.32% per hour quenching rate, and the other which had been treated in the 1550° F./1200° F. near isothermal run described in Example 4 were machined to provide high cycle fatigue test specimens. The samples were tested at 70° F. at a frequency of 30 Hz using an A ratio of 0.99. Baseline cast plus HIP'ed samples (no hydrogen treatment) were machined and tested from the same heat of alloy for comparison purposes. The results of this work are illustrated below and compared with the reported properties of wrought material in FIG. 13.
______________________________________70° F. HIGH CYCLE FATIGUE PROPERTIES OFCAST AND HIP'ED Ti-6Al-4V ALLOY Maximum CycleMaterial Stress toCondition (1) (ksi) Failure comments______________________________________Control 60 10.sup.7 Did not failMaterial (2) 60 10.sup.7 Did not fail 65 10.sup.7 Did not fail 65 9.3 × 10.sup.6 75 4.3 × 10.sup.5 75 3.4 × 10.sup.5 80 1.7 × 10.sup.5Treated According 90 10.sup.7 Did not failto the Invention (3) 100 10.sup.7 Did not fail 100 10.sup.7 Did not failTreated According 100 10.sup.7 Did not failto the Invention (4) 100 10.sup.7 Did not fail 110 10.sup.7 Did not fail 110 5.2 × 10.sup.6 110 4.5 × 10.sup.6 110 3.7 × 10.sup.6 110 2.2 × 10.sup.6______________________________________ (1) After casting and HIP at 1650° F. and 15 ksi for two hours. (2) Tests performed for production heat characterization purposes after 1550° F. anneal for two hours. (3) Isothermal processing at 1450° F. with an average constitutional quenching rate of 0.32% per hour, as described in Example 2. (4) Near isothermal processing at 1550° F./1200° F., as described in Example 4.
The material treated by the present invention demonstrated a stress for 10 7 cycles endurance in excess of 100 ksi. This compared very favorably to the 60 ksi fatigue strength of cast and HIP'ed baseline material obtained from previously tested material, FIG. 13. See, Technical Bulletin TB 1660, Howmet Turbine Components Corporation, "Investment Cast Ti-6Al-4V." In addition, technical literature suggests that the fatigue strength capability of wrought Ti-6Al-4V alloy mill products varies from approximately 65 ksi to 95 ksi (C. A. Celto, B. A. Kosmal, D. Eylon, and F. H. Froes, "Titanium Powder Metallurgy - A Perspective," Journal of Metals, Sept. 1980). Comparison of the above data with this literature data indicates that castings which are processed in accordance with the present invention have fatigue strength capabilities which are competitive with, or greater than, those of forged material.
The microstructual refinement achieved by the present invention may, in certain circumstances, produce an undesirable combination of strength and ductility properties for a specific application. In such situations the microstructural refinement achieved by the process embodiment of the present invention could be combined with subsequent heat treatments to achieve a balance of properties better suited to the desired application of the treated material. For example, the treated material could be subjected to conventional solution and aging treatments (above or below the beta transus in the case of titanium) or annealing processes, or combinations thereof. It is also possible to utilize multiple cycles combining the present invention with more conventional heat treatments in cyclic or multiple steps.
Use of the present invention would not normally refine the prior beta grain size of a casting. Therefore, the benefits of the invention are best combined with optimum casting technology producing fine grain castings.
Although the present invention is particularly suited for net shape castings, it should be understood that the invention is applicable to simple cast shapes, such as ingot castings. The present invention may be used to refine their microstructure and to produce an article that is more desirable as an input stock for subsequent forging operations. One benefit would be that the degree of necessary "breakdown operations" would be reduced. In addition, the present invention could be applied to precision or machined forgings which have been improperly heat treated, as a means to attain useful microstructures and high mechanical property capabilities. This would eliminate the need for further deformation processing which might be impractical or impossible and avoid exposing the article to elevated temperatures that are sufficiently high to solution anneal, distort, contaminate or otherwise impair the material.
An additional advantage of a material treated according to the present invention is that the resultance microstructural refinement lessens the attenuation of energy passing through the treated material. This facilitates the non-destructive testing of the treated material by such methods as ultrasonic inspection, radiography, eddy current and other techniques that input energy to the material and attempt to locate flaws by monitoring the manner in which the energy is absorbed or reflected.
The present invention can be applied to a broad variety of cast materials, including situations where solidification has occurred in a local or restricted region, such as with weldments, plasma or other molten metal deposits, and liquid phase sintered materials. The present invention finds particular utility in applications where cast metals and alloys were not previously suitable. Components (and portions thereof) for gas turbine and other heat engines as well as implanted medical prosthesis are particularly suited as applications of the present invention because of the physical properties of materials treated in accordance with the present invention.
The present invention is also useful in treating input material for other forming or shaping operations. For example cast ingots can be treated according to the present invention. As a result subsequent operations such as forging, rolling, extrusion, wire drawing, etc. are facilitated because of the microstructure of the treated material. Such a technique finds particular utility in forming components for heat engines such as gas turbines, where mechanical deformation to refine the microstructure ("breakdown operations") is reduced or eliminated.
Other applications for the present invention may be devised and the scope of the invention should not be limited solely to the embodiments disclosed. | The microstructure of titanium is refined by inducing a high temperature transformation from α+β to β and back to α+β by diffusing hydrogen into and then out of the metal while maintaining the metal above the temperature of hydride formation. The titanium is heated to a temperature just below the α+β to β transformation temperature, and hydrogen is diffused into the metal thereby inducing the phase change. The hydrogen is diffused out of the metal again inducing a phase change. When the hydrogen has been removed, the metal is allowed to cool to room temperature. | 2 |
FIELD OF THE INVENTION
The present invention relates to mineral mining installations and more particularly to chain tensioning systems for use in such installations.
BACKGROUND TO THE INVENTION
It is well known to win mineral, e.g. coal, with the aid of a machine such as a plough which is hauled back and forth along a scraper-chain conveyor. The plough is propelled with the aid of a chain driven with drive means at a drive station at one end of the conveyor. In such an installation it necessary to adjust the tension in the drive chain from time to time. Normally the drive chain is entrained around a chain wheel in a housing, the so-called "plough box" which is moved along with associated drive motor and gearing in relation to a machine frame of the drive station to adjust the tension.
In DE-OS 2554785 a hydraulic piston and cylinder unit is used to move the plough box. The cylinder of the unit is mounted to a side plate of the frame and the plough box is fixed in a variety of pre-set positions by a locking member such as a bolt, engaging in a row of holes after the unit has adjusted the chain tension.
There is a need for an improved chain tensioning system.
SUMMARY OF THE INVENTION
According to the invention a chain tensioning system is composed of a least one motor driving a self-locking worm gearing. Conveniently the motor is mounted to the plough or housing box and its associated drive and rotates a worm wheel which meshes with a rack fixed to the machine frame and extending in the direction of the chain to be tensioned. In contrast to the known designs it is not necessary to fix the plough box in its desired position after tensioning and the range of tensions which can be controlled is continuous rather than incremental. The motor need only operate when adjustment of tension is required and the plough box will remain in its adjusted position after the motor has been halted. Furthermore the relatively large hydraulic unit used in the previously-mentioned design is replaced by one or more small motors preferably hydraulic motors. In a preferred embodiment two hydraulic motors in the form of reversible radial piston motors drive a common shaft carrying a worm.
The worm gearing is conveniently a reduction gearing of compact size mounted in the plough box or in a subhousing.
The rack is best fixed to a strong bearing plate fitted to the side plate of the machine frame and this bearing plate and the plough box or housing are then provided with guide means such as rails or bars engaged with hooks, claws or flanges.
In a preferred design, a small worm wheel can mesh with the worm driven by the motor or motor and a shaft carrying the small worm wheel also carries a larger worm wheel which actually meshes with the rack. The worm wheel shaft is preferably disposed in the direction of the chain to be tensioned while the worm shaft can extend vertically in the housing of the worm gearing.
It is advisable to have the plough box partly cover the rack and to have the plough box supported by its rear surface on a supplementary sliding surface of the bearing plate. The rack itself is then best recessed or countersunk in the bearing plate with respect to these sliding surfaces.
The teeth and gaps of the rack may have the shape of circular segment.
Preferably the worm gearing is enclosed to prevent the ingress of dirt and its housing can be fixed with screws to the end of the plough box or formed as a sub-housing of the plough box.
The drive motor or motors can be controlled to operate in dependence on the prevailing tension in the chain so that chain tensioning is effected automatically.
The invention may be understood more readily, and various other aspects and features of the invention may become apparent, from consideration of the following description.
BRIEF DESCRIPTION OF DRAWINGS
An embodiment of the invention will now be described, by way of example only, with reference to the accompanying drawings, wherein:
FIG. 1 is a plan view of one end of a mineral mining installation constructed in accordance with the invention;
FIG. 2 is a part sectional end view of part of the installation shown in FIG. 1; and
FIG. 3 is a sectional plan view of part of the installation shown in FIG. 1, the view being taken on a somewhat larger scale to FIG. 1.
DESCRIPTION OF PREFERRED EMBODIMENT
As shown in FIG. 1, a scraper-chain conveyor 1 composed as is known, of a series of channel sections or pans disposed end-to-end has at one end a drive station with a frame 2. The frame 2 has spaced-apart side plates 3, 4 between which there is a drum 5 with a sprocket wheel around which the scraper-chain assembly of the conveyor is entrained. The scraper-chain assembly as such is not illustrated but it is generally represented by the chain-dotted line 6 in FIG. 1. The drum 5 is driven by a drive assembly 7 mounted on the side plate 3. On the opposite side plate 4 there is a housing 8 which forms the so-called plough box in which there is a rotatable toothed drive wheel 9 for driving a chain used for propelling a plough along the conveyor 1. The drive wheel 9 is driven with a drive assembly 10 mounted on the exterior of the housing 8. The housing 8 with the drive assembly 10, which can be composed of a motor and gearing, is movable in relation to the side plate 4 in order to alter the tension in the chain (not shown) entrained around the drive wheel 9.
FIG. 3 shows the housing 8 without the drive assembly 10. The housing 8 has an opening 11 for facilitating the installation and removal of the wheel 9 and through which an output drive shaft of the drive assembly 10 passes. As shown in FIGS. 2 and 3, a stout bearing plate 12 is mounted to the side plate 4 of the frame 2 and preferably the plate 12 is secured to the side plate 4 with screws and shape locked joints, such as mortise and tenon joints 13. The bearing plate 12 has guide bars 14 extending in the direction of the chain tensioning movement at its upper and lower regions and the housing 8 has complementary hooks or claws 15 or the like which slidably engage over the bars 14. The housing 8 is accordingly guided with this guide means 14, 15 by way of the bearing plate 12 and hence in relation to the side plate 4 of the frame 2 for movement in a chain tensioning direction and opposite.
At the end of the housing 8 remote from the conveyor 1 and the plough chain lead-in there is a device or mechanism 16 which serves to effect the movement of the housing 8 to vary the chain tension. The mechanism 16 as shown in FIG. 1 can be connected to an end face of the housing 8 with screws or the like. Alternatively the housing 8 may be extended to form a sub-housing for the mechanism 16.
In accordance with the invention, the mechanism 16 is a self-locking worm gearing and associated drive. As illustrated, the drive may take the form of two hydraulic rotary motors 17, for example radial piston motors which are disposed one above the other in a housing 18 containing at least part of the worm gear.
The motors 17 have drive shafts 19 coupled with sleeves 22 to a common shaft 20 carrying a worm 21. The worm 21 meshes with a worm wheel 23 carried on a shaft 24 rotatably mounted in the housing 18 and extending in the direction of chain tensioning. The shaft 24 also carries a second worm wheel 25 of somewhat larger diameter which meshes with a rack 26 fitted to the plate 12, and extending in the direction of chain tensioning. The rack 26 can be formed with alternate teeth and gaps shaped as circular segments. The worm wheel 25 preferably has a trapezoidal thread and the teeth of the rack 26 are then likewise trapezoidal.
FIG. 3 shows that the housings 8, 18 partly cover the rack 26 on the bearing plate 12.
The housing 8 is supported by its rear surface 27 on a complementary sliding surface 28 of the bearing plate 12. The rack 26 is best countersunk or recessed into the bearing plate 12 towards the side plate 4 relative to the sliding surfaces 27, 28.
The motors 17 which drive the tensioning mechanism have a reversible rotation so as to adjust the chain tension in either sense.
During operation when the motors 17 are switched on the worm gearing, which forms a reduction gearing; displaces the housing 8 with the mechanism 16 itself with respect to the frame 2 so that the chain entrained around the wheel 9 is slackened or tightened as desired. When the tension has been adjusted the motors 17 are switched off and due to the self-locking nature of the worm gearing the housing 8 remains in the adjusted position. With this arrangement the tension in the plough chain can be set to any desired value over a wide range even with relatively long chains. The mechanism 16 is also quite compact and does not occupy undue space.
The worm gearing can be most effectively protected against the ingress of dirt in the housing 18.
The housing 8 and the chain tensioning mechanism 16 can be disposed at the main drive station and/or at the auxiliary drive station usually at the opposite ends of the conveyor 1.
It is possible to replace the double motor drive 17 with a single motor and to use an electric motor or motors instead of the hydraulic motor or motors.
The starting and stopping of the tensioning mechanism motor or motors can be effected automatically in a controlled manner depending on the prevailing chain tension. | A plough box containing a chain wheel driving a chain to propel a chain used to move a plough is mounted for displacement alongside a machine frame at one end of a scraper-chain conveyor. To adjust the tension in the chain a motor is operated to drive a self-locking worm gearing which employs a worm wheel meshing with a rack fixed to the machine frame and extending in the direction of the chain. | 4 |
This application is a US National Stage of International Application No. PCT/CN2013/076992, filed on Jun. 8, 2013, designating the United States, and claiming the benefit of Chinese Patent Application No. 201210201548.3, filed with the Chinese Patent Office on Jun. 15, 2012 and entitled “Method, apparatus and system for updating key”, which is hereby incorporated by reference in its entirety.
FIELD OF THE INVENTION
The present invention relates to the field of communications and particularly to a method, apparatus and system for updating a key.
BACKGROUND OF THE INVENTION
Along with rapid development of smart terminals, there are constantly growing demands of users for the rates and capacities of data services, and thus a traditional single-layer network of coverage by a macro base station (macro eNB) has failed to accommodate the demands of the users. In view of this, this problem has been addressed in the Third-Generation Partnership Project (3GPP) by hierarchical networking so that some low-power base stations (in the forms of femto/pico/relay node or the like) are deployed in an environment with small coverage including a hotspot area, an indoor environment at home, an office environment or the like for the purpose of cell splitting to enable an operator to provide a user with a service at a higher data rate and a lower cost.
However there may be some negative effect accompanying an increase in capacity of the network due to hierarchical networking, where a cell of a low-power base station has such a small coverage area that a moving User Equipment (UE) is handed over too frequently, thus adding a risk of interrupted communication of the UE during the handover.
FIG. 1 illustrates the network architecture of an Evolved Universal Terrestrial Radio Access Network (E-UTRAN), where the E-UTRAN is composed of evolved base stations (eNBs). An eNB functions as an access network and communicates with the UE via an air interface. There are both a control plane connection and a user plane connection between the UE and the eNB. For each UE attached to the network, there is a Mobility Management Entity (MME) serving the UE, and the MME and the eNB are connected with an S1-MME interface. The S1-MME interface provides the UE with a service including the functions of mobility management and bearer management to the control plane.
A Serving Gateway (S-GW) and the eNB are connected with an S1-U interface, and for each UE attached to the network, there is an S-GW serving the UE. The S1-U interface provides the UE with a service to the user plane, and user plane data of the UE is transmitted between the S-GW and the eNB over a bearer of the S1-U interface.
In the existing hierarchical network as illustrated in FIG. 2 , the macro base station provides basic coverage, and a low-power small base station (a local eNB) provides hotspot coverage, where there is a data/signaling interface (which may be a wired or wireless interface) between the local eNB and the macro eNB, and the UE can operate under the macro eNB or the local eNB. Since a cell controlled by the local eNB has a small coverage area and there are a small number of UEs served by the local eNB, the UE connected with the local eNB tends to be provided with a better quality of service, e.g., a higher traffic rate, a higher-quality link, etc. Thus when the UE connected with the macro eNB approaches the cell controlled by the local eNB, the UE can be handed over to the local eNB to be served by the local eNB; and when the UE moves away from the cell controlled by the local eNB, the UE needs to be handed over to a cell by the macro eNB to maintain the wireless connection.
In order to lower the risk of dropped call, there is proposed a network architecture in which the user plane can be separated from the control plane, where the network architecture involves a scenario with hierarchical network deployment of local and macro eNBs.
FIG. 2 illustrates the network architecture in which the user plane can be separated from the control plane. In this way, when the UE is located in the area covered by only the cell of the macro eNB, both the control plane connection and the user plane connection of the UE are active at the macro eNB; and when the UE moves to the area covered by both the cell of the macro eNB cell and the cell of the local eNB, (all or a part of) the user plane bearer connection of the UE is handed over to the local eNB for a higher traffic rate; and the control plane connection is still maintained at the macro eNB to thereby prevent a dropped call of the UE due to a failure in the control plane connection handover.
In the event that the user plane of the UE is separated from the control plane, the UE is connected with both of the eNBs concurrently.
In the event that user plane is separated from the control plane, FIG. 3 and FIG. 4 illustrate protocol stacks between the UE and the network. The user plane eNB of the UE (e.g., the local eNB, when a part of the user plane bearer of the UE is active at the local eNB, the macro eNB is also provided with the user plane protocol stack) provides the UE with the function of transmitting user plane data but without any peer Radio Resource Control (RRC) layer provided for the UE so that no RRC control can be performed on the UE; and the control plane eNB of the UE (e.g., the macro eNB) provides the UE with the function of transmitting a control plane message, and in order to carry and process an RRC message, the macro eNB needs to be provided with a peer user plane protocol stack for the UE. Since a Non-Access Stratum (NAS) message needs to be carried in an RRC message, the serving MME of the UE is connected with the control plane eNB of the UE.
In the existing protocol, an RRC connection is composed of three Signaling Radio Bearers (SRBs), which are an SRB0, an SRB1 and an SRB2, where no processing at the Packet Data Convergence Protocol (PDCP) layer is necessary for the SRB0. At the user plane, a plurality of Data Radio Bearers (DRBs) can be set up between the UE and the eNB. PDCP entities correspond to the DRBs/SRB1/SRB2, and each DRB, the SRB1 and the SRB2 correspond respectively to a set of PDCP entities. Thus there may be a plurality of sets of PDCP entities for the UE.
Security of the air interface between the UE and the eNB is protected at the PDCP layer. An RRC message is encrypted and integrity protected at the PDCP layer, and a user data packet transmitted over a DRB is encrypted for protection. The UE and the eNB negotiate in the RRC message about a security algorithm of the air interface and calculate a key for the air interface and then configure the Packet Data Convergence Protocol (PDCP) layer with the key for use.
Each data packet is assigned with a sequence number, denoted as a count value, at the PDCP layer. The UE and the eNB maintain an uplink count value and a downlink count value respectively for each PDCP entity. The count values increase gradually as the data packets are transmitted until they reach their maximums wrap around to zero.
For security protection, the count values at the PDCP layers are one of input parameters, where each count value is used only once. The count values are introduced to thereby ensure that each data packet is encrypted or integrity protected using different security parameters so as to lower the possibility of cracking information contents by an intruder. The eNB and UE will change the key by handover when the counts reach their maximums. At present the length of the counts is 32 bits.
For the architecture where there are only user plane functions on the local eNB, the local eNB can not update the key for the air interface but the key will be updated by the macro eNB. Neither can the macro eNB be aware real time information about the count values at the PDCP layer on the local eNB nor can the local eNB be aware of information about the PDCP count values corresponding to the SRBs or a part of the DRBs (if any) on the macro eNB.
Since the key update process is typically performed by the macro eNB, when some PDCP count value of some UE reaches a preset value, the key update flow is initiated to update the key. However since the macro eNB can not be aware of real time information about the count values at the PDCP layer on the local eNB, such a situation may occur that PDCP count value of some DRB on the local eNB has wrapped around whereas the original user plane key is still being used between the UE and the local eNB so that the same set of security parameters have been used twice, thus increasing the possibility of cracking communication information of the UE by the intruder and degrading the security performance of the network.
SUMMARY OF THE INVENTION
Embodiments of the invention provide a method, apparatus and system for updating a key so as to improve the security performance of a network.
An embodiment of the invention provides a method of updating a key, the method including:
a small base station monitoring user plane uplink PDCP count value or user plane downlink PDCP count value of each UE connected with the small base station; and
the small base station transmitting a key update request as a function of the user plane uplink PDCP count value or the user plane downlink PDCP count value to a macro base station so that the macro base station updates a key in response to the key update request or the small base station transmitting information about the user plane uplink PDCP count value or the user plane downlink PDCP count value to the macro base station so that the macro base station updates a key according to the information about the user plane uplink PDCP count value or the user plane downlink PDCP count value.
An embodiment of the invention provides a method of updating a key, the method including:
a macro base station receiving a key update request transmitted by a small base station to the macro base station as a function of user plane uplink PDCP count value or user plane downlink PDCP count value, or information transmitted by the small base station to the macro base station about the user plane uplink PDCP count value or the user plane downlink PDCP count value; and
the macro base station updating a key in response to the key update request or according to the information about the user plane uplink PDCP count value or the user plane downlink PDCP count value.
An embodiment of the invention provides an apparatus for updating a key, the apparatus including:
a monitoring unit configured to monitor user plane uplink PDCP count value or user plane downlink PDCP count value of each UE connected with the apparatus;
a transmitting unit configured to transmit a key update request as a function of the user plane uplink PDCP count value or the user plane downlink PDCP count value to a macro base station so that the macro base station updates a key in response to the key update request or to transmit information about the user plane uplink PDCP count value or the user plane downlink PDCP count value to the macro base station so that the macro base station updates a key according to the information about the user plane uplink PDCP count value or the user plane downlink PDCP count value.
An embodiment of the invention provides an apparatus for updating a key, the apparatus including:
a receiving unit configured to receive a key update request transmitted by a small base station to a macro base station as a function of user plane uplink PDCP count value or user plane downlink PDCP count value, or information transmitted by the small base station to the macro base station about the user plane uplink PDCP count value or the user plane downlink PDCP count value; and
an updating unit configured to update a key in response to the key update request or according to the information about the user plane uplink PDCP count value or the user plane downlink PDCP count value.
An embodiment of the invention provides a system for updating a key, the system including a small base station and a macro base station, wherein:
the small base station is configured to monitor user plane uplink PDCP count value or user plane downlink PDCP count value of each UE connected with the small base station; and to transmit a key update request as a function of the user plane uplink PDCP count value or the user plane downlink PDCP count value to a macro base station or to transmit information about the user plane uplink PDCP count value or the user plane downlink PDCP count value to the macro base station; and
the macro base station is configured to receive the key update request transmitted by the small base station to the macro base station as a function of the user plane uplink PDCP count value or the user plane downlink PDCP count value, or the information transmitted by the small base station to the macro base station about the user plane uplink PDCP count value or the user plane downlink PDCP count value; and to update a key in response to the key update request or according to the information about the user plane uplink PDCP count value or the user plane downlink PDCP count value.
The embodiments of the invention provide a method, apparatus and system for updating a key, where a small base station monitors user plane uplink PDCP count value or user plane downlink PDCP count value of each UE connected with the small base station and transmits information about the user plane uplink PDCP count value or the user plane downlink PDCP count value to a macro base station so that the macro base station updates a key according to the information about the user plane uplink PDCP count value or the user plane downlink PDCP count value, or transmits a key update request as a function of the PDCP count values to a macro base station so that the macro base station updates a key in response to the key update request to thereby avoid security parameters from being reused so as to update the key in a timely manner and improve the security performance of the network.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 illustrates the network architecture of the Evolved Universal Terrestrial Radio Access Network (E-UTRAN) in the prior art;
FIG. 2 illustrates a schematic diagram of the scenario with layered deployment of the network in the prior art;
FIG. 3 illustrates a schematic diagram of the user plane protocol stack in the prior art;
FIG. 4 illustrates a schematic diagram of the control plane protocol stack in the prior art;
FIG. 5 illustrates a first flow chart of a method of updating a key according to an embodiment of the invention;
FIG. 6 illustrates a flow chart of a method of updating a key according to a first embodiment of the invention;
FIG. 7 illustrates a flow chart of transmission of messages according to the first embodiment of the invention;
FIG. 8 illustrates a flow chart of a method of updating a key according to a second embodiment of the invention;
FIG. 9 illustrates a flow chart of transmission of messages according to the second embodiment of the invention;
FIG. 10 illustrates a second flow chart of a method of updating a key according to an embodiment of the invention;
FIG. 11 illustrates a first schematic structural diagram of an apparatus for updating a key according to an embodiment of the invention;
FIG. 12 illustrates a second schematic structural diagram of an apparatus for updating a key according to an embodiment of the invention; and
FIG. 13 illustrates a schematic structural diagram of a system for updating a key according to an embodiment of the invention.
DETAILED DESCRIPTION OF THE EMBODIMENTS
Embodiments of the invention provide a method, apparatus and system for updating a key, where a small base station monitors user plane uplink PDCP count value or user plane downlink PDCP count value of each UE connected with the small base station and transmits information about the user plane uplink PDCP count value or the user plane downlink PDCP count value to a macro base station so that the macro base station updates a key according to the information about the user plane uplink PDCP count value or the user plane downlink PDCP count value, or transmits a key update request as a function of the PDCP count values to a macro base station so that the macro base station updates a key in response to the key update request to thereby avoid security parameters from being reused so as to update the key in a timely manner and improve the security performance of the network.
As illustrated in FIG. 5 , a method of updating a key according to an embodiment of the invention includes:
In the step S 501 , a small base station monitors user plane uplink PDCP count value or user plane downlink PDCP count value of each UE connected with the small base station; and
IN the step S 502 , the small base station transmits a key update request as a function of the user plane uplink PDCP count value or the user plane downlink PDCP count value to a macro base station so that the macro base station updates a key in response to the key update request or transmits information about the user plane uplink PDCP count value or the user plane downlink PDCP count value to the macro base station so that the macro base station updates a key according to the information about the user plane uplink PDCP count value or the user plane downlink PDCP count value.
Particularly in the step S 502 , the small base station transmits the key update request as a function of the user plane uplink PDCP count value or the user plane downlink PDCP count value to the macro base station so that the macro base station updates a key in response to the key update request or transmits the information about the user plane uplink PDCP count value or the user plane downlink PDCP count value to the macro base station so that the macro base station updates a key according to the information about the user plane uplink PDCP count value or the user plane downlink PDCP count value particularly in the following two particular implementations:
In a first implementation, the small base station transmits the key update request including identifier information of a UE, for which a key needs to be updated, to the macro base station upon determining that the user plane uplink PDCP count value or the user plane downlink PDCP count value reaches a preset value; and at this time the macro base station updates the key for the UE according to the identifier information upon reception of the key update request; and
In a second implementation, the small base station transmits the user plane uplink PDCP count value or the user plane downlink PDCP count value of each UE to the macro base station dependent upon a preset report condition; and at this time for each UE, the macro base station updates the key for the UE upon determining that one of the user plane uplink PDCP count value, the user plane downlink PDCP count value, a control plane uplink PDCP count value and a control plane downlink PDCP count value of the UE reaches a preset value.
Particularly the preset report condition is as follows:
There is such at least one of the user plane uplink PDCP count value or the user plane downlink PDCP count value that changes by a preset threshold or more; or
There has been a preset period of time since a last report.
Particularly the macro base station updates the key for the UE in the following particular process:
The macro base station initiates an intra-cell handover procedure so that the macro base station calculates with the UE a new key for Radio Resource Control (RRC) message and user plane data; and
The macro base station returns a key update response message carrying the new key to the small base station.
In order to further ensure the data to be decrypted correctly, transmission of the data can be avoided as much as possible in the update key process, and at this time the method further includes:
The UE transmits no uplink data for a preset period of time but decrypts received downlink data using the new key and the old key after the key is updated; or
The small base station neither transmits downlink data to the UE nor schedules the UE to transmit uplink data for a preset period of time after transmitting the key update request to the macro base station; or
The macro base station transmits a notification message to the small base station upon determining from the user plane uplink PDCP count value, the user plane downlink PDCP count value, the control plane uplink PDCP count value and the control plane downlink PDCP count value of the UE that the key is to be updated for the UE, and the small base station neither transmits downlink data to the UE nor schedules the UE to transmit uplink data for a preset period of time after receiving the notification message.
The method of updating a key according to the embodiment of the invention will be described below in particular embodiments thereof.
First Embodiment
In this embodiment, a small base station triggers a key update according to user plane uplink PDCP count value or user plane downlink PDCP count value of a UE.
As illustrated in FIG. 6 , the method includes:
In the step S 601 , a local eNB monitors user plane uplink PDCP count value or user plane downlink PDCP count value of each DRB of each UE connected with the local eNB;
In the step S 602 , when the user plane uplink PDCP count value or the user plane downlink PDCP count value of an UE reaches a specific value, the local eNB transmits a key update request carrying the identifier of the UE to a macro eNB so that the macro eNB can identify the specific UE for which a key needs to be updated;
The identifier of the UE carried in the message can be a C-RNTI or can be an interface application layer identifier, and particularly the identifier can be transmitted to the local eNB before the macro eNB configures the local eNB with the DRBs, e.g., a C-RNTI, or can be an interface application layer identifier (e.g., an X2AP ID or an S1 AP ID) when the macro eNB configures the local eNB with the DRBs.
Since the local eNB receives a new key at some delay, in order to ensure no problem with decryption between the local eNB and the UE, the UE may transmit no uplink data for some period of time after the key is updated but decrypt downlink data received from the local eNB respectively using the new and old keys; or the local eNB may neither schedule the UE to transmit uplink data nor transmit downlink data to the UE until receiving the new key after transmitting the key update request to the macro eNB. Of course correct decryption can be ensured otherwise at both of the transmitting and receiving sides in the embodiment of the invention.
In the step 603 , the macro eNB performs a key update process with the specified UE upon reception of the key update request, for example, by initiating an intra-cell handover procedure so that the macro eNB and the UE calculate a new key for RRC message and user plane data;
In the step 604 , the macro eNB returns a key update command message carrying the newly calculated key for the user plane data to the local eNB; and
In the step 605 , the local eNB protects with the UE the user plane data using the new user plane key upon reception of the new key and returns an acknowledgment message to the macro eNB.
Particularly the transmitted messages between the macro base station and the small base station can be embodied as messages illustrated in FIG. 7 , where the small base station transmits a Key Update Request to the macro base station, the macro base station transmits a Key Update Command to the small base station upon determining the new key, and the small base station returns a Key Update Acknowledge to the macro base station.
Second Embodiment
In this embodiment, a small base station transmits user plane uplink PDCP count value or user plane downlink PDCP count value of respective UEs conditionally to a macro base station.
As illustrated in FIG. 8 , the method includes the following steps:
In the step S 801 , a local eNB monitors user plane uplink PDCP count value or user plane downlink PDCP count value of each DRB of each UE connected with the local eNB and transmits the user plane uplink PDCP count value or the user plane downlink PDCP count value of each DRB of the UE conditionally to a macro eNB, for example, by transmitting the PDCP count values in a Sequence Number (SN) report message carrying the identifier of the UE;
“Conditionally” refers to that the user plane uplink PDCP count value or the user plane downlink PDCP count value are transmitted each time they are increased by some amount or transmitted each time some period of time elapses;
In the step S 802 , the macro eNB decides from the received user plane uplink PDCP count value or user plane downlink PDCP count value of the UE whether to initiate a key update process or when to initiate a key update process. Upon determining that an air interface key needs to be updated, the macro eNB performs a key update process with the specified UE, for example, by initiating an intra-cell handover procedure so that the macro eNB and the UE calculate a new key for RRC message and user plane data;
Since the local eNB receives a new key at some delay, in order to ensure no problem with decryption between the local eNB and the UE, the UE may transmit no uplink data for some period of time after the key is updated but decrypt downlink data received from the local eNB respectively using the new and old keys; or the macro eNB firstly notifies the local eNB after deciding to update the key with the UE. The local eNB may neither schedule the UE to transmit uplink data nor transmit downlink data to the UE until receiving the new key after receiving the notification. Of course correct decryption can be ensured otherwise at both of the transmitting and receiving sides in the embodiment of the invention.
In the step 803 , the macro eNB returns a key update command message carrying the newly calculated key for the user plane data to the local eNB; and
In the step 804 , the local eNB protects with the UE the user plane data using the new user plane key upon reception of the new key and returns an acknowledgment message to the macro eNB.
Particularly the transmitted messages between the macro base station and the small base station can be embodied as messages illustrated in FIG. 9 , where the small base station transmits the user plane uplink PDCP count value or the user plane downlink PDCP count value of the respective UEs to the macro base station in an SN report, the macro base station transmits a Key Update Command to the small base station upon determining the new key, and the small base station returns a Key Update Acknowledge to the macro base station.
In the embodiment of the invention, the control plane base station and the user plane base station monitor control plane PDCP count values and the user plane PDCP count values of the UE respectively, and both of them can update an air interface key when any of the count values reaches a preset value to thereby update the key in a timely manner.
An embodiment of the invention further provides a method of updating a key, and as illustrated in FIG. 10 , the method includes:
In the step S 1001 , a macro base station receives a key update request transmitted by a small base station to the macro base station as a function of user plane uplink PDCP count value or user plane downlink PDCP count value, or information transmitted by the small base station to the macro base station about the user plane uplink PDCP count value or the user plane downlink PDCP count value;
In the step S 1002 , the macro base station updates a key in response to the key update request or according to the information about the user plane uplink PDCP count value or the user plane downlink PDCP count value.
In correspondence to the first embodiment, in the step S 1001 , the macro base station receives the key update request transmitted by the small base station to the macro base station as a function of the user plane uplink PDCP count value or the user plane downlink PDCP count value particularly as follows:
The macro base station receives the key update request transmitted by the small base station to the macro base station upon the small base station determines that the user plane uplink PDCP count value or the user plane downlink PDCP count value reaches a preset value, where the key update request includes identifier information of a UE for which a key needs to be updated; and
At this time in the step S 1002 , the macro base station updates the key in response to the key update request particularly as follows:
The macro base station updates the key for the UE according to the identifier information upon reception of the key update request.
In correspondence to the second embodiment, in the step S 1001 , the macro base station receives the information about the user plane uplink PDCP count value or the user plane downlink PDCP count value transmitted by the small base station particularly as follows:
The macro base station receives the user plane uplink PDCP count value or the user plane downlink PDCP count value of each UE transmitted by the small base station dependent upon a preset report condition;
At this time in the step S 1002 , the macro base station updates the key according to the information about the user plane uplink PDCP count value or the user plane downlink PDCP count value particularly as follows:
For each UE, the macro base station updates the key for the UE upon determining that one of the user plane uplink PDCP count value, the user plane downlink PDCP count value, a control plane uplink PDCP count value and a control plane downlink PDCP count value of the UE reaches a preset value.
Particularly the preset report condition is as follows:
There is such at least one of the respective PDCP count values that changes by a preset threshold or more; or
There has been a preset period of time since a last report.
Particularly the macro base station updates the key for the UE as follows:
The macro base station initiates an intra-cell handover procedure so that the macro base station calculates with the UE a new key for RRC message and user plane data; and
The macro base station returns a key update response message carrying the new key to the small base station.
In correspondence to the first embodiment, in order to ensure correct decryption of the data, the UE transmits no uplink data but decrypts received downlink data using the new key and the old key for a preset period of time after the key is updated; or the small base station neither transmits downlink data to the UE nor schedules the UE to transmit uplink data for a preset period of time after transmitting the key update request to the macro base station; or
In correspondence to the second embodiment, in order to ensure correct decryption of the data, the UE transmits no uplink data for a preset period of time but decrypts received downlink data using the new key and the old key after the key is updated; or the macro base station transmits a notification message to the small base station upon determining that the key is to be updated for the UE, and the small base station neither transmits downlink data to the UE nor schedules the UE to transmit uplink data for a preset period of time after receiving the notification message.
An embodiment of the invention provides an apparatus for updating a key, and the apparatus can be particularly a small base station as illustrated, the apparatus including:
A monitoring unit 1101 is configured to monitor user plane uplink PDCP count value or user plane downlink PDCP count value of each UE connected with the apparatus;
A transmitting unit 1102 is configured to transmit a key update request as a function of the user plane uplink PDCP count value or the user plane downlink PDCP count value to a macro base station so that the macro base station updates a key in response to the key update request or to transmit information about the user plane uplink PDCP count value or the user plane downlink PDCP count value to the macro base station so that the macro base station updates a key according to the information about the user plane uplink PDCP count value or the user plane downlink PDCP count value.
In correspondence to the first embodiment, the transmitting unit 1102 is particularly configured:
To transmit the key update request including identifier information of a UE, for which a key needs to be updated, to the macro base station upon determining that the user plane uplink PDCP count value or the user plane downlink PDCP count value reaches a preset value so that the macro base station updates the key for the UE according to the identifier information upon reception of the key update request.
In correspondence to the second embodiment, the transmitting unit 1102 is particularly configured:
To transmit the user plane uplink PDCP count value or the user plane downlink PDCP count value of each UE to the macro base station dependent upon a preset report condition so that for each UE, the macro base station updates the key for the UE upon determining that one of the user plane uplink PDCP count value, the user plane downlink PDCP count value, a control plane uplink PDCP count value and a control plane downlink PDCP count value of the UE reaches a preset value.
In correspondence to the first embodiment, the transmitting unit 1102 is further configured:
To neither transmit downlink data to the UE nor schedule the UE to transmit uplink data for a preset period of time after transmitting the key update request to the macro base station.
In correspondence to the first embodiment, the transmitting unit 1102 is further configured:
To receive a notification message transmitted by the macro base station upon determining that the key is to be updated for the UE and to neither transmit downlink data to the UE nor schedule the UE to transmit uplink data for a preset period of time after receiving the notification message.
An embodiment of the invention further provides an apparatus for updating a key, and the apparatus can be particularly a macro base station as illustrated in FIG. 12 , the apparatus including:
A receiving unit 1201 is configured to receive a key update request transmitted by a small base station to a macro base station as a function of user plane uplink PDCP count value or user plane downlink PDCP count value, or information transmitted by the small base station to the macro base station about the user plane uplink PDCP count value or the user plane downlink PDCP count value; and
An updating unit 1202 is configured to update a key in response to the key update request or according to the information about the user plane uplink PDCP count value or the user plane downlink PDCP count value.
In correspondence to the first embodiment, the receiving unit 1201 is particularly configured:
To receive the key update request transmitted by the small base station to the macro base station upon the small base station determines that the user plane uplink PDCP count value or the user plane downlink PDCP count value reaches a preset value, where the key update request includes identifier information of a UE for which a key needs to be updated; and
At this time the updating unit 1202 is particularly configured:
To update the key for the UE according to the identifier information upon reception of the key update request.
In correspondence to the first embodiment, the receiving unit 1201 is particularly configured:
To receive the user plane uplink PDCP count value or the user plane downlink PDCP count value of each UE transmitted by the small base station dependent upon a preset report condition; and
At this time the updating unit 1202 is particularly configured:
For each UE, to update the key for the UE upon determining that one of the user plane uplink PDCP count value, the user plane downlink PDCP count value, a control plane uplink PDCP count value and a control plane downlink PDCP count value of the UE reaches a preset value.
The updating unit 1020 configured to update the key for the UE is particularly configured:
To initiate an intra-cell handover procedure so that the macro base station calculates with the UE a new key for RRC message and user plane data; and
To return a key update response message carrying the new key to the small base station.
In correspondence to the first embodiment, the updating unit 1202 is further configured:
To transmit a notification message to the small base station upon determining that the key is updated for the UE so that the small base station neither transmits downlink data to the UE nor schedules the UE to transmit uplink data for a preset period of time after receiving the notification message.
An embodiment of the invention further correspondingly provides a system for updating a key as illustrated in FIG. 13 , the system including a small base station 1301 and a macro base station 1302 , where:
The small base station 1301 is configured to monitor user plane uplink PDCP count value or user plane downlink PDCP count value of each UE connected with the small base station; and to transmit a key update request as a function of the user plane uplink PDCP count value or the user plane downlink PDCP count value to a macro base station 1302 or to transmit information about the user plane uplink PDCP count value or the user plane downlink PDCP count value to the macro base station 1302 ; and
The macro base station 1302 is configured to receive the key update request transmitted by the small base station 1301 to thereto as a function of the user plane uplink PDCP count value or the user plane downlink PDCP count value, or the information transmitted by the small base station thereto about the user plane uplink PDCP count value or the user plane downlink PDCP count value; and to update a key in response to the key update request or according to the information about the user plane uplink PDCP count value or the user plane downlink PDCP count value.
The embodiments of the invention provide a method, apparatus and system for updating a key, where a small base station monitors user plane uplink PDCP count value or user plane downlink PDCP count value of each UE connected with the small base station and transmits information about the user plane uplink PDCP count value or the user plane downlink PDCP count value so that the macro base station updates a key according to the information about the user plane uplink PDCP count value or the user plane downlink PDCP count value, or transmits a key update request as a function of the PDCP count values to a macro base station so that the macro base station updates a key in response to the key update request to thereby avoid security parameters from being reused so as to update the key in a timely manner and improve the security performance of the network.
Those skilled in the art shall appreciate that the embodiments of the invention can be embodied as a method, a system or a computer program product. Therefore the invention can be embodied in the form of an all-hardware embodiment, an all-software embodiment or an embodiment of software and hardware in combination. Furthermore the invention can be embodied in the form of a computer program product embodied in one or more computer useable storage mediums (including but not limited to a disk memory, a CD-ROM, an optical memory, etc.) in which computer useable program codes are contained.
The invention has been described in a flow chart and/or a block diagram of the method, the device (system) and the computer program product according to the embodiments of the invention. It shall be appreciated that respective flows and/or blocks in the flow chart and/or the block diagram and combinations of the flows and/or the blocks in the flow chart and/or the block diagram can be embodied in computer program instructions. These computer program instructions can be loaded onto a general-purpose computer, a specific-purpose computer, an embedded processor or a processor of another programmable data processing device to produce a machine so that the instructions executed on the computer or the processor of the other programmable data processing device create means for performing the functions specified in the flow(s) of the flow chart and/or the block(s) of the block diagram.
These computer program instructions can also be stored into a computer readable memory capable of directing the computer or the other programmable data processing device to operate in a specific manner so that the instructions stored in the computer readable memory create an article of manufacture including instruction means which perform the functions specified in the flow(s) of the flow chart and/or the block(s) of the block diagram.
These computer program instructions can also be loaded onto the computer or the other programmable data processing device so that a series of operational steps are performed on the computer or the other programmable data processing device to create a computer implemented process so that the instructions executed on the computer or the other programmable device provide steps for performing the functions specified in the flow(s) of the flow chart and/or the block(s) of the block diagram.
Although the preferred embodiments of the invention have been described, those skilled in the art benefiting from the underlying inventive concept can make additional modifications and variations to these embodiments. Therefore the appended claims are intended to be construed as encompassing the preferred embodiments and all the modifications and variations coming into the scope of the invention.
Evidently those skilled in the art can make various modifications and variations to the invention without departing from the spirit and scope of the invention. Thus the invention is also intended to encompass these modifications and variations thereto so long as the modifications and variations come into the scope of the claims appended to the invention and their equivalents. | The present invention relates to communications technologies, and disclosed are a key updating method, device, and system. A local eNB monitors a user plane uplink and downlink PDCP COUNT value of each UE connected thereto, and transmits user plane uplink and downlink PDCP COUNT value information or transmits a key update request based on the PDCP COUNT value to a macro eNB, so that the macro eNB updates a key according to the key update request or the user plane uplink and downlink PDCP COUNT value information, thereby avoiding the problem of repeated use of security parameters, realizing prompt key update, and improving the security performance of the network. | 7 |
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application is a continuation-in-part of U.S. patent application Ser. No. 13/267,691, filed Oct. 6, 2011, which claims the benefit of U.S. Provisional Application No. 61/390,354, filed Oct. 6, 2010, the entire disclosures of which are hereby incorporated herein by reference in their entirety.
FIELD OF THE INVENTION
[0002] Embodiments of the present invention are generally related to selectively opening and closing one or more ports or access openings in a tubular string. More specifically, one embodiment allows selective access of a tubular annulus of a wellbore to provide a flow path between a tubular string positioned in the wellbore and a geologic formation that requires a treatment such as hydraulic fracturing.
BACKGROUND OF THE INVENTION
[0003] A wellbore used in recovering oil/gas typically includes a production string placed within a casing string. In some wellbore designs, the entire length of the wellbore is lined with the casing string, which is cemented within the wellbore. Alternatively, in open-hole designs, the casing string is limited to an upper portion of the wellbore and lower portions of the wellbore are open. In both open-hole and cased-hole designs, the production string is typically placed into the lower portions of the wellbore and mechanical or hydraulic packers are used to radially secure the production string in a predetermined location. The outside diameter of the production tubing is less than the diameter of the internal wellbore or production casing, thereby defining a tubular annulus.
[0004] To gain access to oil/gas deposits in the general area of the wellbore, selected portions of the production casing are perforated or, alternatively, sliding sleeves or other devices are used to provide a conduit to the oil and gas deposits. To enhance the flow of oil/gas into the tubular annulus, and to thus increase flow into the production tubing, hydraulic fracturing (i.e., “fracing”) of subterranean formations may be required, especially in low permeability formations. That is, in some instances subterranean formation that the wellbore penetrates does not possess sufficient permeability for the economic production of oil/gas so hydraulic fracturing and/or chemical stimulation of the subterranean formation is needed to increase flow performance.
[0005] Hydraulic fracturing consists of selectively injecting fracturing fluids into a subterranean formation in openhole or via perforations or other openings in the production casing of the wellbore at high pressures and rates to form a fracture. In addition, granular proppant materials, such as sand, ceramic beads, or other materials are injected into the formation with the fracturing fluids to hold the fracture open after the hydraulic pressure has been released. The proppant material prevents the fracture from closing and thus provides a more permeable flow path within the subterranean formation, resulting in increased flow capacity. In chemical stimulation treatments, permeability and thus flow capacity is improved by dissolving materials in the formation or otherwise chemically changing formation properties.
[0006] To gain access to multiple or layered reservoirs, or a very thick hydrocarbon-bearing formation by hydraulic fracturing, multiple fracturing zones are established and stimulated in stages. One technique currently being used with significant results utilizes the use of a directionally drilled well into a single reservoir. By drilling the well in a substantially horizontal orientation through the reservoir, the reservoir can be fractured in multiple locations to substantially improve the flow rate. To stimulate multiple fracturing zones, a target stimulation zone must be temporarily isolated from the already-stimulated zones to prevent injecting fluids into the already-stimulated zones. Various methods have been utilized to achieve zonal isolation, although numerous drawbacks to the current methods exist.
[0007] A common method currently used to isolate a fracturing zone in multistage fracturing utilizes composite bridge plugs. According to this method, the deepest zone in the wellbore (or most distal in horizontal wellbores) is stimulated. Then, the stimulated zone is isolated by a bridge plug that is positioned above the perforations associated with the stimulated zone. The process is repeated in the next zone up the wellbore. At the end of the stimulation process, a wellbore clean-out operation removes the bridge plug. The major disadvantages of using one or more bridge plugs to isolate a fracture stimulated zone are the high cost and risk of complications associated with multiple trips into and out of the wellbore to position the plugs. For example, bridge plugs can become stuck in the wellbore and need to be drilled out at great expense. A further disadvantage is that the required wellbore cleanout operation may block or otherwise damage some of the successfully fractured zones.
[0008] Another method used to isolate a fracturing zone utilizes frac baffles and balls. The first baffle, which contains the smallest inside diameter, is placed in the most distal portion of the wellbore. The succeeding baffles increase in diameter and are installed above the previous baffle. To achieve zonal isolation, a frac ball of a predetermined size is dropped that seats on the corresponding frac baffle at a specified depth or position to block a portion of the wellbore. The isolated zone is accessed by perforations or a sleeve is shifted then stimulated. After each stage, the process is repeated until all selected frac zones in the well are fracture stimulated. On the last day of operation, the frac balls typically are flowed back to the surface during the flow back of the fracturing fluids. The primary advantage of this method is that the frac baffles are installed within the casing and can be activated by dropping a ball from the surface, with little downtime between fracture stimulation stages. The disadvantages include the need to use progressively larger sized balls for subsequent fracturing stages, thus limiting the number of zones that can be treated for a given casing diameter. Additionally, the frac baffles and balls may need to be milled out of the casing string, which increases the number of wellbore operations and inherent risks and costs associated therewith.
[0009] One method for successfully isolating one or more production zones utilizes a sliding sleeve that is associated with a tubular string, which may include casing, liners, tubing, etc. Opening the sleeve permits zonal isolation and stimulation of the formation via the tubular string through the selected sleeve. The sleeve can be operated by using a mechanical/hydraulic shifting tool attached to coiled or jointed tubular or by using a ball-drop system. In a ball-drop system, a ball pumped down the tubular string engages a sliding sleeve and shifts the sleeve from a closed position to an open position, thereby opening a passageway to the tubular annulus. The ball also isolates the already-stimulated zones located beneath the open sleeve. The advantages of this method are that the tubular annulus can be accessed without requiring various tools or costly trips into the wellbore to isolate the various formations. However, the method is limited by the need to use progressively larger sized balls for subsequent fracturing stages, thus limiting the number of zones that can be deployed for a given tubing string diameter. This system inherently restricts the production flow rate due to the necessity of using progressively smaller balls to open and close the sleeves.
[0010] Accordingly, a need exists for an improved downhole tools and methods that efficiently isolates individual zones of a subterranean formation while (1) ensuring that stimulation fluids are directed to the desired location, (2) maintaining a desired inner diameter of the tubing string, (3) reducing the time between stimulations, and (4) is mechanically simplistic to operate and cost effective.
[0011] The following disclosure describes improved downhole tools and methods for selectively isolating downstream portions of a tubular string while simultaneously allowing access to the tubular annulus of a wellbore such that a selected zone may be stimulated. The improved downhole tools and methods do not limit the number of fracture stimulation stages created in a vertical or directional wellbore. As used herein, ‘downstream’ and ‘lower’ refers to the distal portions of a tubular string disposed toward the toe of the wellbore. Further, as used herein, ‘treatment fluid’ may comprise acid, proppant material, gels, or other stimulation fluids generally used in the art.
SUMMARY OF THE INVENTION
[0012] The downhole tools disclosed herein is designed for downhole well stimulation for oil and gas wells, but could be used for any downhole application where a shifting sleeve is used to selectively divert flow. Additionally, the downhole tools may be employed in either open or cased holes. Generally, a downhole tool is placed into a wellbore and provides for the opening of the tubular string to the geologic formation while simultaneously restricting the flow of fluid and proppant downstream of the downhole tool. Fluid with or without proppant is then pumped into the geologic formation through the openings to stimulate the rock through hydraulic fracturing (fracing) or other treatment processes. By progressing from the toe (bottom) of the well back toward the surface, it is possible to stimulate the subterranean formation in stages, thus improving the quality of the stimulation and/or minimizing fluid/proppant. The downhole tools disclosed herein improve upon existing shifting sleeve designs by 1) allowing for a very large number of stimulation stages (50-200), 2) minimizing the flow restrictions inherent in ball drop systems that rely on progressively smaller ball diameters, 3) providing a system that does not need to be drilled out in order to facilitate production, 4) using a single ball size for all stages, and 5) improving the speed and efficiency of the stimulation process.
[0013] It is thus one aspect of embodiments of the present invention to provide a downhole tool that seals a selected portion of a wellbore between geologic formations while simultaneously allowing access to a tubular annulus defined between the interior of a casing string or open-hole wellbore and a production string positioned therein. According to at least one embodiment, the downhole tool is integrated by a threaded connection, or any similar connection commonly practiced in the art, into a tubular production string that is positioned within the wellbore. The downhole tool provides a path for fluids or tools to enter the tubular annulus and simultaneously isolates downstream portions of the tubular production string from the high pressures exerted by a stimulation procedure, e.g., hydraulic fracturing. Additionally, with the use of packers or cement to isolate the tubular annulus, the downhole tool isolates non-targeted stimulation zones from the high pressures exerted by a stimulation procedure. As used herein, packers may be swellable, hydraulic, mechanical, inflatable, or any other alternative known in the art. The downhole tool in some instances eliminates the need to perforate various strings of pipe or position other tools into the wellbore, thus saving time, costs, and the inherent risk of trapping a tool. The downhole tool may be constructed of metallic or non-metallic materials, such as the composite materials currently used in composite bridge plugs, and typically combinations of both.
[0014] It is another aspect of embodiments of the present invention to provide a downhole tool that employs a flapper valve that is capable of moving between a first position and a second position to selectively open and close an axial bore and a lateral bore of the downhole tool. The axial bore of the downhole tool opens to and is in fluid communication with an internal bore of the tubular string. The lateral bore of the downhole tool opens to and creates a passageway to the tubular annulus. The flapper valve may be associated with a sealing element fabricated of an elastomeric, plastic, metallic, or any other sealing element known to one of ordinary skill in the art. In some embodiments, the flapper valve may be comprised of degradable materials. For example, after a predetermined period of time, the flapper valve may dissolve to allow production fluid to flow unrestricted through the axial and lateral bores of the downhole tool. A degradable flapper valve is disclosed in U.S. Pat. No. 7,287,596, which is incorporated herein by reference in its entirety.
[0015] When in the first position, the flapper valve seals the lateral bore of the downhole tool such that fluid may be pumped through the axial bore of the downhole tool. The axial bore of the downhole tool may also allow passage of solid elements, such as wireline tools, tubing, coiled tubing conveyed tools, cementing plugs, balls, darts, and any other elements known in the art. The sealing area of the first position may be irregular in shape and comprised of several sealing surfaces.
[0016] When in the second position, the flapper valve seals the axial bore of the downhole tool, thereby sealing the internal bore of the tubular string and allowing fluid to be pumped to the tubular annulus through the lateral bore of the downhole tool. The movement of the flapper from the first position to the second position effectively seals the downstream stimulation zone and opens a passageway to the tubular annulus, allowing the next stimulation zone to be immediately treated.
[0017] It is another aspect of embodiments of the present invention to provide a restraining mechanism for maintaining the flapper in the first position. The restraining mechanism may be a ring, finger, a tubular member, such as a sleeve, or any other restraining device. The restraining mechanism exerts a force against the flapper valve to prevent external forces acting upon the outside of the flapper valve, such as the external pressures associated with circulating a fluid in the tubular annulus, from unseating the flapper valve from its first position. When the restraining device is disengaged, the flapper valve is free to move to the second position. According to at least one embodiment, the restraining mechanism is disengaged by an actuating mechanism deployed on electric wireline, a slickline, coiled tubing, jointed tubing, solid rods, or drop members. Examples of drop members include balls, plugs, darts, or any other members commonly used in the art. As used herein, ‘ball’ refers to any shaped device that is feasible of being pumped down a tubular string and is not limited to a circular-shaped device. For example, a ‘ball’ may be circular, oval, oblong, or any other shape known in the art.
[0018] It is another aspect of embodiments of the present invention to provide a flapper valve that is biased toward the second position by a coiled spring, leaf spring band, or other similar energy storage system. The stored energy assists the movement of the flapper valve toward the second position. According to at least one embodiment, a spring is placed in the body of the downhole tool, and compressed, storing mechanical energy to aid in the movement of the flapper valve from the first position to the second position. Additionally, an explosive device may be used to assist the flapper valve movement. For example, cement located in the tubular annulus may interfere with flapper movement and the spring or explosive device would aid in breaking the flapper valve away from the cement. The activating tool used to move the flapper valve-restraining device also may assist in the movement of the flapper valve from the first position to the second position.
[0019] It is another aspect of embodiments of the present invention to provide a downhole tool that is activated with drop members from the surface using a multi-pressure activation system. The multi-pressure activation system exposes the downhole tool to a predetermined pressure to selectively actuate a sliding sleeve that receives a drop member. For example, in one embodiment, a first higher pressure does not actuate the sliding sleeve. Instead, the higher pressure causes the drop member to pass through the axial bore of the downhole tool, by use of a spring operated catch mechanism, and travel through the internal bore of the tubular string to the next tool or to the distal end of the wellbore. The higher pressure may either deform the drop member to allow it to pass through the axial bore of the downhole tool or actuate a ball catch mechanism, such as a collet slidable device, collet deformable fingers, or any other ball catch mechanism currently employed in the art. Collet slidable devices are disclosed in U.S. Pat. Nos. 4,729,432, 4,823,882, 4,893,678, 5,244,044, and 7,373,974, which are incorporated herein by reference in their entireties. Collet deformable fingers are disclosed in U.S. Pat. Nos. 4,292,988 and 5,146,992, which are incorporated herein by reference in their entireties.
[0020] In the above mentioned embodiment, a second lower pressure does not allow the drop member to pass through the axial bore of the downhole tool. Rather, the lower pressure keeps the drop member trapped, under pressure, in the axial bore of the downhole tool. The lower pressure is held for a period of time until the sliding sleeve moves, thereby allowing the flapper valve to move from the first position to the second position to block the axial bore of the tubular string and to open the lateral bore of the downhole tool.
[0021] In operation, the drop member would be inserted into the tubular string. Once the drop member lands and engages the sleeve of a downhole tool, a higher pressure would be exerted at the surface of the wellbore. The higher pressure would cause the drop member to pass through that downhole tool without sleeve actuation, and continue to pass through each tool distally in the wellbore until the desired tool is reached. The sleeve of the desired downhole tool would then be activated by applying the lower pressure, which would move the sleeve and allow the flapper valve to actuate from the first position to the second position. Fracture stimulation materials may then be selectively pumped through the internal bore of the tubular string, through the lateral bore of the downhole tool, and into the tubular annulus.
[0022] In another embodiment, utilizing hydraulics in the catch mechanism would allow a drop member to pass under a lower pressure; shifting would occur only under a higher pressure.
[0023] Another aspect of embodiments of the present invention is to provide a sliding sleeve associated with a reservoir of hydraulic oil or other fluid that allows the sliding sleeve to shift, thereby freeing the flapper valve to move from the first position to the second position. The hydraulic oil or other fluid bleeds through an orifice to a second reservoir allowing the sliding sleeve to move over a period of time from an initial position to a position that allows the flapper to move. The sliding sleeve may be moved back to its first position by means of a spring or other stored energy device, which would in turn transfer the hydraulic fluid back through the orifice to the first reservoir.
[0024] It is another aspect of embodiments of the present invention to provide a locking mechanism for securing a sliding sleeve in a shifted position. The locking mechanism prevents the sliding sleeve from shifting back to its initial position, thereby ensuring that the sliding sleeve does not disengage the flapper valve from its second position.
[0025] It is another aspect of embodiments of the present invention to provide a downhole tool that is activated by coiled tubing or small diameter jointed tubing. In this embodiment, the treatment for a given wellbore stimulation would be pumped in an annulus formed between the coiled tubing, solid rods, and the inner surface of a tubular string, thereby allowing the coiled tubing to function as a dead string to monitor down hole treating pressures. A tool located at the end of the coiled tubing engages a shifting sleeve associated with the tubing string that is held in place by shear pins or any other similar device. The use of coiled tubing as the actuating tool allows an unlimited number of treatment stages to be performed in a well, thus providing an advantage over frac baffles, for example, which require smaller actuation balls to be used to engage frac baffles in more distal positions in the wellbore. Additionally, using coiled tubing as the activation member removes the need for pressurizing fluid pumped from the surface as described above, and the coiled tubing may be used to cleanout proppant between fracing stages.
[0026] Another aspect of embodiments of the present invention is to provide a downhole tool utilizing a shifting sleeve that closes the tubular production string at a predetermined location and opens the annulus of the wellbore to allow fracing or other stimulation procedures in stages. In one embodiment a counter is embedded in the shifting sleeve and a uniform size ball is dropped into the well. Each shifting sleeve is preset with a unique counter number such that the counter locks in place after the proper number of balls have passed, catching and retaining the next ball. The ball then closes off the wellbore and shifts a sliding sleeve, opening the annulus and geologic formation to be treated at a predetermined depth or interval. The counter locking mechanism is designed to facilitate normal completion operations including flow back during screen out. As used herein, counting means refers to any form of counter that can increment and/or decrement. Sleeve activation means identifies any means that facilitates movement of an inner tubular member, such as a sleeve. For example, sleeve activation means include pressure activation, mechanical activation, and electronic activation techniques. Signal means identifies any form of electronic signal that is capable of conveying information.
[0027] Another aspect of embodiments of the present invention is to provide a swellable ball that is dropped into the well and a downhole tool utilizing a sliding sleeve. The ball is configured to swell after a predetermined period of time in a fluid, such as fracing fluid. In operation, the swellable ball is pumped quickly to the correct location. The location can be verified by counting pressure spikes, which result from the ball passing through a seat disposed in a sliding sleeve. Once the swellable ball is located in the tubular string proximal to the sleeve to be shifted, pumping is discontinued. Thus, the swellable ball would be allowed to swell to a size that would prevent the ball from passing through the selected sleeve. The operator would then continue pumping.
[0028] Another aspect of embodiments of the present invention is to provide a smart ball that is dropped into the well and a downhole tool utilizing a sliding sleeve. In one embodiment, the shifting sleeve has an embedded radio frequency identification (“RFID”) chip and the smart ball has an RFID reader built into it. When the ball passes the RFID chip, the RFID reader reads the number of the RFID chip. If the correct number is read, the ball releases a mechanism that expands the size of the ball. For example, the expansion could be a split in the middle of the ball that rotates part of the ball slightly. Alternatively, the top ⅓ of the ball may be hinged and would open upon the correct number being read. The larger ball would become stuck in the next seat. In another embodiment, the smart ball includes a timer that causes the ball to expand after a certain period of time. For example, in this embodiment, an operator would count the pressure spikes and stop pumping when the ball is in the right location and wait for the timer to go off. Pumping would then resume.
[0029] Another aspect of embodiments of the present invention is to provide a ball that is dropped into the well and a downhole tool utilizing a smart sleeve. In one embodiment, each sleeve has an RFID reader and the ball has an RFID chip. When the correct ball passes, the device releases a mechanism to catch the ball, plugging the orifice and shifting the sleeve. In another embodiment, each sleeve has a pressure transducer and circuit board with logic to understand pressure signals. The sleeve receives hydraulic pressure signals from a signal generator on the surface. The proper signal triggers the sleeve to shift, thus opening the annulus and creating a seat for the ball to land on. Then, a ball is dropped to close off the axial bore of the tubular production string.
[0030] It is another aspect of the present invention to provide a method for selectively treating multiple portions of a production wellbore, whether from the same geologic formation or different formations penetrated by the same wellbore. In one embodiment, a single sized ball is utilized multiple times to move a sleeve which isolates a lower portion of the wellbore, while providing communication to the annulus to treat the formation at a predetermined depth. After that zone is treated, subsequent balls of the same size are used to isolate and treat other zones at a shallower depth. After all the zones are treated, all of the balls may flow back to the surface, or disintegrate if manufactured from degradable materials. Dissolvable balls are disclosed in U.S. Patent Publication No. 2010/0294510, which is herein incorporated by reference in its entirety.
[0031] It is still yet another aspect of embodiments of the present invention to provide a downhole tool that employs an external cover associated with the lateral bore of the downhole tool. The external cover prevents debris, such as cement, from interfering with the movement of the flapper from the first position to the second position. The external cover may be removed or deformed by fluid pumped through the internal bore of the tubular string and the axial bore of the downhole tool. Coiled tubing carrying fluids alone or fluids with abrasive particles may also be used to remove or deform the external cover, which will also form a tunnel through the cement to the formation. It is another aspect of embodiments of the present invention to provide a downhole tool that is used with external tubular packers positioned within the tubular annulus to isolate a stimulation zone and to prevent clogging of the lateral bore. External casing packers, conventional packers, swellable packers, or any other similar devices may be employed. External tubular packers isolate the frac zone and/or prevent cement from contacting the external portion of the downhole tool and blocking the lateral bore.
[0032] Another aspect of embodiments of the present invention is to provide a downhole tool that facilitates tools exiting the tubular string through the lateral bore. According to at least one embodiment, the flapper valve may be longer in one axis such that when the flapper valve moves to the second position, it forms a whipstock slide that is angled with respect to a longitudinal axis of the tubular string. The whipstock slide guides drilling or workover tools to the lateral bore of the downhole tool. If the lateral bore is blocked by an external cover or by debris, the blockage may be removed by milling, drilling, acid, or other fluid, including abrasive particle laden fluids. Using the flapper valve as a whipstock slide may be particularly useful for short and ultra-short radius horizontal boreholes where the tubular string is the origin. The flapper valve may have an orienting mechanism, such as a crowsfoot's key that is commonly used to orient tools in a specified azimuth. When the flapper valve is in the second position, the orienting mechanism orients the tools to the lateral bore.
[0033] According to another aspect of embodiments of the present invention, the downhole tool may include several longitudinally spaced flapper valves. Additionally, numerous smaller flapper valves could be arranged around the circumference of the downhole tool. The smaller flapper valves could be activated by an activating member as described above to open one or more additional bores to the tubular annulus. After being released by an activating member, the smaller flapper valves would move toward a second position, which may be disposed in a recess about the body of the downhole tool so as not to block the axial bore of the downhole tool.
[0034] It is another aspect of embodiments of the present invention to provide a downhole tool that includes a flapper valve that does not open a lateral bore to the tubular annulus. In these embodiments, movement of an inner tubular member, such as a sleeve, opens ports to the annulus that allow fluid exchange between the axial bore of the tubular string and the subterranean formation. The movement of the inner tubular member allows the flapper valve to block the axial bore of the tubular string and thereby prevent fluid flow through the axial bore of the downhole tool to portions of the tubular string located downstream of the actuated flapper valve.
[0035] It is another aspect of embodiments of the present invention to provide a downhole tool that may be used as a blowout preventer that prevents a large volume of fluid from passing upward through the internal bore of the tubular string. According to at least one embodiment, a downhole tool includes a flapper valve and an inner tubular member. The flapper has two stationary positions, a first position and a second position. When the flapper valve is in the first position, fluid may be freely pumped through the axial bore of the downhole tool. When the flapper is in the second position, the internal bore of the tubular string is sealed such that fluids downstream of the flapper valve cannot flow upward through the axial bore of the downhole tool. In this embodiment, the inner tubular member is pressure activated and comprises a ball, a ball seat, a ball cage, and flow restriction orifices. The inner tubular member is held in place by shear pins or any other similar means known in the art that are responsive to axial force.
[0036] The inner tubular member allows fluid to be pumped from the surface in normal circulation and in reverse circulation. During normal circulation, fluid flows down the tubular string through the ball seat and the flow restriction orifices of the inner tubular member. The ball cage restricts the ball from moving distally in the tubular string. During reverse circulation, fluid flows up the tubular string causing the ball to seat in the ball seat, thus limiting the upward fluid flow by requiring the fluid to flow through flow restriction orifices. If a large volume of fluid attempted to pass upward through the downhole tool, such as in a blowout situation, the friction pressure through the orifices would overcome the shear pins, or any other similar means and shift the inner tubular member upwards. The upward shift of the inner tubular member allows the flapper valve to move from the first position to the second position. Once in the second position, the flapper valve seals the internal bore of the tubular member and fluid flow up the internal bore of the tubular string would be prevented. The flapper valve may have a sealing element fabricated of an elastomeric, plastic, metallic, or any other sealing elements customarily used in the art to prevent fluids from flowing up the inner bore of the tubular string. The sealing elements may be disposed on the flapper or on a flapper seat. Additionally, the downhole tool may include multiple flapper valves.
[0037] According to at least one embodiment of the present invention, a downhole tool adapted for use in a tubular string to selectively treat one or more hydrocarbon production zones is provided, the downhole tool comprising: an upper end and a lower end adapted for interconnection to a tubular string; a catch mechanism positioned proximate to said lower end and adapted to selectively catch or release a ball traveling through said tubular string; a sleeve which travels in a longitudinal direction between a first position and a second position, and which is actuated based on an internal pressure in the tubular string, said sleeve preventing a flow of a treatment fluid in a lateral direction into an annulus of the wellbore while in said first position, and permitting the flow of the treatment fluid in the lateral direction through at least one port in said second position; and a locking mechanism positioned proximate to said catch mechanism, wherein when said catch mechanism is engaged with said locking mechanism, said sleeve is in said second position and said treatment fluid cannot be pumped downstream of said catch mechanism in the tubular string.
[0038] According to at least another embodiment of the present invention, a method for treating a plurality of hydrocarbon production zones at different locations in one or more geologic formations is disclosed, the method comprising: providing a wellbore with an upper end, a lower end and a plurality of producing zones positioned therebetween; positioning a string of production tubing in the wellbore, said string of production tubing having an upper end and a lower end; providing a plurality of selective opening tools in said production string, each of said selectively opening tools having a catch mechanism adapted to selectively catch or release a ball traveling through said tubular string, a sleeve which travels in a longitudinal direction between a first position and a second position and which is actuated based on an internal pressure in the tubular string, said sleeve preventing a flow of a treatment fluid in a lateral direction into an annulus of the wellbore while in said first position, and permitting the flow of the treatment fluid in the lateral direction through at least one port in said second position, and a locking mechanism positioned proximate to said catch mechanism, wherein when said catch mechanism is engaged with said locking mechanism, said sleeve is in said second position and said treatment fluid cannot be pumped downstream of said catch mechanism in the tubular string; pumping a treatment fluid containing a ball through the production tubing at a predetermined first pressure until said ball engages the catch mechanism of a first selective opening tool positioned proximate to a first portion of the hydrocarbon production zone; maintaining said first pressure in said production tubing for a pre-determined period of time to displace said catch mechanism of said first tool and engage the locking mechanism of said first tool wherein a sleeve of said first tool is in a second position; pumping the treatment fluid into said first portion of said at least one geologic formation; reducing the pressure in said production tubing wherein said catch mechanism disengages from said locking mechanism and said sleeve returns to said first position; pumping said treatment fluid at a predetermined second pressure until said ball engages and passes through said catch mechanism of said first selective opening tool, said second pressure higher than said first pressure; reducing said treatment fluid pressure to said first pressure to position said ball in a catch mechanism of a second selective opening tool positioned proximate to a second zone of the hydrocarbon production zone, wherein said catch mechanism engages a locking mechanism of said second tool wherein a sleeve of said second tool is in second position; pumping the treatment fluid into said second portion of said at least one geologic formation.
[0039] According to yet another embodiment of the present invention, system adapted for use in a tubular string for treating one or more hydrocarbon production zones, comprising: a plurality of downhole tools, each comprising: an upper end and a lower end adapted for interconnection to a tubular string; a catch mechanism positioned proximate to said lower end and adapted to selectively catch or release a ball traveling through said tubular string; a sleeve which travels in a longitudinal direction between a first position and a second position, and which is actuated based on an internal pressure in the tubular string, said sleeve preventing a flow of a treatment fluid in a lateral direction into an annulus of the wellbore while in said first position, and permitting the flow of the treatment fluid in the lateral direction through at least one port in said second position; and a locking mechanism positioned distal to said catch mechanism, wherein when said catch mechanism is engaged with said locking mechanism, said sleeve is in said second position and said treatment fluid cannot be pumped downstream of said catch mechanism in the tubular string; wherein when a treatment fluid containing a ball is pumped into said tubular string at a predetermined first pressure, said ball displaces a catch mechanism of a first downhole tool until engaging a locking mechanism of said first tool wherein a sleeve of said first tool is in a second position; wherein when a treatment fluid containing a ball is pumped into said tubular string at a predetermined second pressure greater than said first pressure, said ball passes through said catch mechanism of said first downhole tool until engaging a catch mechanism of a second downhole tool.
[0040] The Summary of the Invention is neither intended nor should it be construed as being representative of the full extent and scope of the present invention. Moreover, references made herein to “the present invention” or aspects thereof should be understood to mean certain embodiments of the present invention and should not necessarily be construed as limiting all embodiments to a particular description. The present invention is set forth in various levels of detail in the Summary of the Invention as well as in the attached drawings and the Detailed Description of the Invention and no limitation as to the scope of the present invention is intended by either the inclusion or non-inclusion of elements, components, etc. in this Summary of the Invention. Additional aspects of the present invention will become more readily apparent from the Detail Description, particularly when taken together with the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0041] The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the invention and together with the general description of the invention given above and the detailed description of the drawings given below, serve to explain the principles of these inventions.
[0042] FIG. 1 is a cross-sectional view of a fracture stimulation system according to one embodiment of the present invention;
[0043] FIG. 2 is a cross-sectional view of a well production system according to one embodiment of the present invention;
[0044] FIG. 3 is a cross-sectional view of a downhole tool that is actuated by a shifting tool according to one embodiment of the present invention;
[0045] FIG. 4 is another cross-sectional view of the embodiment of FIG. 3 ;
[0046] FIG. 5 is a cross sectional view of a horizontal well with multiple fracturing stages;
[0047] FIG. 6 is a cross-sectional view of a downhole tool that is actuated by a pressure activation system according to one embodiment of the present invention;
[0048] FIG. 7 is another cross-sectional view of the embodiment of FIG. 6 ;
[0049] FIG. 8 is yet another cross-sectional view of the embodiment of FIG. 6 ;
[0050] FIG. 9 is a cross-sectional view of a downhole tool that is actuated by a pressure activation system according to another embodiment of the present invention;
[0051] FIG. 10 is a cross-sectional view of the downhole tool shown in FIG. 9 in a non-shifted position;
[0052] FIG. 11 is a cross-sectional view of the downhole tool shown in FIG. 9 in a shifted position;
[0053] FIG. 12 is a cross-sectional view of the downhole tool shown in FIG. 11 during flow-back;
[0054] FIG. 13 is a cross-sectional view of a downhole tool that is actuated by a counter system according to yet another embodiment of the present invention;
[0055] FIG. 14 is a cross-sectional view of the downhole tool shown in FIG. 13 in a shifted position;
[0056] FIG. 15 is an end view of the downhole tool shown in FIG. 13 ;
[0057] FIG. 16 is a side view of the counter assembly shown in FIG. 13 ;
[0058] FIG. 17 is a top view of the counter assembly shown in FIG. 16 ;
[0059] FIG. 18 is a side view of a locking mechanism in a clockwise lock position;
[0060] FIG. 19 is a side view of the locking mechanism of FIG. 18 in a counterclockwise lock position;
[0061] FIG. 20 is a side view of a counter assembly according to another embodiment of the present invention;
[0062] FIG. 21 is another side view of the counter assembly shown in FIG. 20 ;
[0063] FIG. 22 is a cross-sectional view of a downhole tool that is employed as a whipstock slide according to one embodiment of the present invention;
[0064] FIG. 23 is another cross-sectional view of the embodiment of FIG. 22 ;
[0065] FIG. 24 is a cross-sectional view of a downhole tool that is configured to prevent a well blowout according one embodiment of the present invention;
[0066] FIG. 25 is another cross-sectional view of the embodiment of FIG. 24 ;
[0067] FIG. 26 is yet another cross-sectional view of the embodiment of FIG. 24 ;
[0068] FIG. 27 is a further cross-sectional view of the embodiment of FIG. 24 ;
[0069] FIG. 28 is yet a further cross-sectional view of the embodiment of FIG. 24 ;
[0070] FIG. 29A is a cross-sectional view of a downhole tool in an unactuated state under a low axial bore pressure, the tool actuated by a drop member and catch/release mechanism according to another embodiment of the present invention;
[0071] FIG. 29B is a cross-sectional top view of section A-A of the catch/release mechanism of the embodiment of FIG. 29A ;
[0072] FIG. 29C is a detailed cross-sectional side view of portion A of the catch/release mechanism of the embodiment of FIG. 29A ;
[0073] FIG. 30A is a cross-sectional view of the downhole tool shown in FIG. 29A in an actuated state under a low axial bore pressure;
[0074] FIG. 30B is a detailed cross-sectional side view of portion A of the downhole tool shown in FIG. 30A ;
[0075] FIG. 31A is a cross-sectional view of the downhole tool shown in FIG. 29A under a high axial bore pressure;
[0076] FIG. 31B is a cross-sectional top view of section A-A of the downhole tool shown in FIG. 31A ;
[0077] FIG. 31C is a detailed cross-sectional side view of portion A of the downhole tool shown in FIG. 31A ;
[0078] FIG. 31D is a cross-sectional view of the downhole tool shown in FIG. 31A under a high axial bore pressure after passage of the drop member;
[0079] FIG. 32A is a cross-sectional view of a downhole tool in an unactuated state under a high axial bore pressure during retrieval of the drop member; and
[0080] FIG. 32B is a detailed cross-sectional side view of portion A of the downhole tool shown in FIG. 32A .
[0081] In certain instances, details that are not necessary for an understanding of the invention or that render other details difficult to perceive may have been omitted. It should be understood, of course, that the invention is not necessarily limited to the particular embodiments illustrated herein.
[0082] To assist in the understanding of one embodiment of the present invention the following list of components and associated numbering found in the drawings is provided.
[0000]
#
Components
2
Downhole tool
6
Wellbore
10
Subterranean formation
14
Tubular string
16
Packer
18
Axial bore
22
Lateral bore
26
Fracture ports
30
Flapper valve
34
Sliding sleeve
38
Stimulation fluid
42
Shifting tool
46
Production fluid
50
Shear pins
54
Hinge
58
Torsion spring
62
Compression spring
66
Fracturing zones
70
Sleeve
74
High pressure
78
Drop member
82
Catch mechanism
86
Lower pressure
88
Flange
90
Spring
92
Spring force
94
Upper reservoir
98
Lower reservoir
102
Orifice
106
Radial port
110
Seals
114
Weep hole
118
Sleeve locking mechanism
122
Recess
126
Downhole tool
130
Shifting sleeve
132
Counter assembly
134
Counter mechanism
138
Counter locking mechanism
142
Rocker mechanism
146
Counter spring
150
Counter window
154
Perforations
158
Protrusion
162
Chamber
166
Pressure equalization device
170
Manual setting mechanism
174
Trip pin
178
Gears
180
Counter wheels
182
Inner shaft
186
Sliding lock
190
Anchor
192
Treatment fluid
194
Radial button
196
Rack
198
Gear
206
Fill material
210
Inner tubular member
212
Outer tubular member
214
Sealing element
218
Ball
218 A
Ball position A
218 B
Ball position B
222
Ball seat
226
Ball cage
230
Flow restriction orifices
240
Piston
240 A
Piston position A
240 B
Piston position B
242
Fluid reservoir
250
Catch/Release Mechanism
252
Collet Finger
254
Major inner diameter
256
Minor inner diameter
258
Deformed distal collet finger
260
Locking mechanism
270
Locking dog
DETAILED DESCRIPTION
[0083] FIGS. 1 and 2 show one embodiment of the present invention in which at least one downhole tool 2 and associated tubular string 14 is disposed in a wellbore 6 . According to this embodiment, the wellbore 6 is drilled through a subterranean formation. As shown in FIGS. 1 and 2 , three tools 2 are connected to a tubular string 14 . Each tool 2 is vertically disposed within a formation 10 A, 10 B, 10 C that has been selected to be fracture stimulated and/or produced. One of skill in the art will appreciate that packers, cement, or other sealants may be located on either side of the formation 10 A, 10 B, and 10 C to provide annular hydraulic isolation. As shown in FIG. 1 , packers 16 provide annular hydraulic isolation of formation 10 B. In this embodiment, each tool 2 has an axial bore 18 , a lateral bore 22 , fracture ports 26 , a flapper valve 30 , and a sliding sleeve 34 .
[0084] Referring now to FIG. 1 , a fracture stimulation of a multiple zone formation is shown. As illustrated, the lower formation 10 C has been fracture stimulated, the intermediate zone 10 B is currently being fracture stimulated, and the upper zone 10 A will be fracture stimulated in the future. Stimulation fluid 38 flows down the tubular string 14 (which includes downhole tools 2 A, 2 B and 2 C), through the downhole tool 2 A and into the downhole tool 2 B (identifying Tool 2 in formation B). As shown, the downhole tool 2 B has been actuated wherein the flapper valve 30 blocks the axial bore 18 of tool 2 B, thereby preventing fluid from entering a distal portion of the tubular string 14 below the flapper valve 30 of tool 2 B. The fluid 38 flows through the frac ports 26 and the lateral bore 22 of the downhole tool 2 B into the intermediate zone 10 B. Portions of the tubular string 14 not associated with the zone being stimulated may be isolated by cement, packers, etc.
[0085] After the fracture stimulation of the intermediate zone 10 B is completed, a shifting tool 42 is conveyed down the tubular string 14 to the downhole tool 2 A. The shifting tool 42 activates the downhole tool 2 A by shifting the sleeve 34 , thereby releasing the flapper valve 30 . Once released, the flapper valve 30 moves toward its second position and blocks the axial bore 18 of the downhole tool 2 A to fracturing zone 10 A prevent fluid from flowing distally in the tubular string 14 . The second position may be held in place by a variety of locking means that are well known to one of ordinary skill in the art. The shifting tool 42 is removed from the tubular string 14 or repositioned within the tubular string 14 to the next stimulation zone. Stimulation fluid 38 is then pumped down the tubular string 14 , through the activated tool 2 A, and into the fracturing zone 10 A. As will be appreciated by one skilled in the art, this fracture sequence can be repeated without limit in a wellbore. Additionally, more than one downhole tool 2 may be deployed within each formation 10 .
[0086] Referring now to FIG. 2 , production of a multiple zone formation is shown. As illustrated in FIG. 2 , three vertically displaced (or horizontally placed zones in a directional well) formations 10 are producing fluid and/or gas (hereinafter “fluid”). The three downhole tools 2 integrated into the tubular string 14 allow the production fluid 46 to enter and flow up the tubular string 14 . Flapper valves 30 open in response to fluid flow and pressure, allowing flow from both outside and below the downhole tool 2 . As shown, production fluid 46 is flowing from the stimulated zones 10 through the frac ports 26 and the lateral bore 22 of the vertically displaced tools 2 into the tubular string 14 . Once in the tubular string 14 , the production fluid 46 flows up the tubular string 14 . The flapper valve 30 in each respective tool 2 is moved between a first position, where the lateral bore 22 is blocked, and a second position, in which the flapper valve 30 blocks the axial bore 18 , in response to fluid flow and pressure from outside and below the respective tool 2 .
[0087] FIGS. 3 and 4 show a downhole tool according to another embodiment of the present invention. According to this embodiment, a sleeve 34 restrains a flapper valve 30 in its first position, thus closing a lateral bore 22 of the downhole tool 2 . A shifting tool shifts the sleeve 34 , thereby releasing the flapper valve 30 and allowing the flapper valve 30 to move toward its second position.
[0088] FIG. 3 shows the flapper valve 30 is restrained in its first position by the sleeve 34 . The sleeve 34 is held in place by shear pins 50 , which prevent the sleeve 34 from moving within the tubular string 14 . In this position, the axial bore 18 of the downhole tool 2 allows fluids and solid elements to pass through the downhole tool 2 into distal portions of the tubular string 14 , and the flapper valve 30 blocks access to a tubular annulus formed between the tubular string 14 and the wellbore. The sleeve 34 blocks the ports 26 and the flapper valve 30 blocks the lateral bore 22 .
[0089] Referring now to FIG. 4 , the sleeve 34 has been shifted in the downhole tool 2 , thereby releasing a flapper valve 30 from its first position. A hinge 54 connected to the bottom of the flapper valve 30 allows rotation. A torsion spring 58 connected to the bottom of the flapper valve 30 biases the flapper valve 30 towards its second position. A compressed spring 62 also may be included in the body of the downhole tool 2 to assist the movement of the flapper valve 30 from its first position toward its second position. As shown, the flapper valve 30 is in its second position to seal the axial bore 18 of the downhole tool 2 , thereby preventing fluid from flowing downward into distal portions of the tubular string 14 . Frac ports 26 and the lateral bore 22 of the downhole tool 2 create passageways to the annulus of the tubular string 14 . As will be appreciated by one of skill in the art, the lateral bore 22 is optional. Accordingly, in some embodiments, fluid exchange occurs solely through the frac ports 26 .
[0090] Referring now to FIG. 5 , a horizontal well with multiple producing zones is shown. As illustrated, a wellbore 6 is depicted which contains five fractured zones 66 . At least one downhole tool 2 but preferably five in this example may be disposed within the wellbore to isolate and allow production from the different zones in the geologic formation. Each of the downhole tools 2 may be activated by a sleeve 34 as discussed above or by a pressure activation system to allow the selective treatment of each zone and subsequent production simultaneously, thus optimizing economic performance of the producing formation. Although not shown, the fractured producing zones may be hydraulically isolated with packers or cement, for example, to isolate the annular space between the tubular string 14 and the wellbore or casing.
[0091] FIGS. 6-8 illustrate a downhole tool 2 according to another embodiment wherein the downhole tool 2 is actuated by a pressure activation system. More specifically, the sleeve 70 is pressure activated such that the flapper valve 30 is released depending on the pressure exerted into the tubular string 14 . In operation, a high pressure 74 applied to the tubular string 14 does not actuate a downhole tool 2 . Instead, the high pressure 74 causes a drop member 78 , such as a ball, to pass through a downhole tool 2 and travel to the next tool 2 in the tubular string 14 or to the distal portion of the wellbore 6 . The drop member 78 passes through the downhole tool 2 by deforming or by actuating a catch mechanism 82 , as shown in FIGS. 6-8 .
[0092] A lower pressure 86 actuates the downhole tool 2 by shifting the sleeve 70 , thereby releasing a flapper valve 30 and allowing it to move from its first position to its second position. More specifically, the lower pressure 86 acts upon the drop member 78 , which is lodged in the catch mechanism 82 , to slide the sleeve 70 away from the flapper valve 30 . Using a flange 88 , the sleeve contacts and compresses a spring 90 as it moves. The sleeve 70 is associated with an upper reservoir 94 , a lower reservoir 98 , and an orifice 102 for fluid passage. The outer surface of the sleeve 70 forms a boundary between the reservoirs 94 , 98 and the internal bore of the downhole tool 2 , and seals the reservoirs 94 , 98 from pressure in the tubular string. Sealing elements may be provided to enhance the seal between the sleeve 70 and the reservoirs 94 , 98 . Once the sleeve 70 is moved a predetermined distance, the flapper valve 30 is able to release. In one embodiment, a high pressure 74 of about 3000 psi causes the drop member 78 to pass through a downhole tool 2 , and a lower pressure 86 of about 1000 psi maintained in the tubular string 14 for roughly 15 seconds causes the drop member 78 to move the sleeve 70 . One of ordinary skill in the art would understand this embodiment uses a similar mechanism to that of a hydraulic fishing jar. As will be appreciated by one of skill in the art, the pressures may vary depending on design of the sleeve 70 , the drop member 78 , the catch mechanism 82 , and the spring 90 . Further design criteria include the depth of the wellbore, pressure from the producing formation, diameter of tubing string 14 , etc.
[0093] FIG. 8 shows a shifted sleeve 70 and a released flapper valve 30 in its second position. Once the sleeve 70 no longer abuts the flapper valve 30 , a torsion spring 58 will rotate the flapper valve 30 from its first position toward its second position, thereby blocking the axial bore 18 of the downhole tool and opening the lateral bore 22 of the downhole tool. An additional spring 62 may be used to assist the movement of the flapper valve 30 from its first position towards the second position.
[0094] FIGS. 9-12 illustrate a downhole tool 2 actuated by a pressure activation system according to another embodiment of the present invention. The downhole tool 2 shown in FIGS. 9-12 operates in a similar fashion as that described above in connection with FIGS. 6-8 . A flapper valve 30 is shown in FIGS. 9-12 ; however, in some embodiments, the flapper valve 30 is not included in the downhole tool 2 . In these embodiments, the sleeve 70 blocks access to the tubular annulus while in a non-shifted position. A drop member 78 shifts the sleeve 70 to allow access to the subterranean formation through openings formed in the circumference of the downhole tool 2 . The drop member 78 remains seated in the catch mechanism 82 during stimulation of the selected stage to isolate downstream portions of the tubular string from the stimulation fluid and/or proppant.
[0095] Referring to FIG. 9 , a sleeve 70 is disposed in an initial, non-shifted position. As shown, the sleeve 70 blocks access to the tubular annulus through a radial port 106 and restrains the flapper valve 30 in its first position, thereby blocking lateral bore 22 . Seals 110 provide a fluid tight engagement between the sleeve 70 and the downhole tool 2 , thus preventing fluid exchange between the tubular production string and the tubular annulus. The sleeve 70 is interconnected to a flange 88 , which is associated with an upper reservoir 94 and a lower reservoir 98 . The flange 88 has a weep hole 114 that allows fluid exchange between the upper and lower reservoirs. In operation, the weep hole 114 acts like a dashpot and resists motion of the sleeve 70 . The rate of fluid exchange between the upper and lower reservoirs increases once the flange 88 enters the larger cross-sectional reservoir area. Accordingly, in at least one embodiment, the sleeve 70 shifts at two different rates. Initially, the sleeve 70 shifts at a slow rate because of the restricted fluid flow through the weep hole 114 . However, once the sleeve has shifted to the point that the flange 88 enters the larger cross-section reservoir area, the sleeve shifts at an increased rate because of the increased fluid flow path between the upper reservoir 94 and the lower reservoir 98 .
[0096] As illustrated in FIG. 9 , a drop member 78 is seated in a catch mechanism 82 . At higher pressures, the drop member 78 passes through the catch mechanism 82 and travels to the next downhole tool 2 in the tubular production string, as shown in FIG. 10 . At lower pressures, the drop member 78 remains seated in the catch mechanism 82 and moves the sleeve 70 into a shifted position, as shown in FIG. 11 .
[0097] Referring to FIG. 10 , the sleeve 70 remains in a non-shifted position and the drop member 78 has passed through the catch mechanism 82 and is travelling through the tubular string toward a downstream tool 2 disposed in the tubular production string. Referring to FIG. 11 , the drop member 78 has shifted the sleeve 70 , thus allowing the flapper valve 30 to isolate the downstream portions of the tubular production string. A sleeve locking mechanism 118 prevents the sleeve 70 from shifting upward in the downhole tool 2 and unseating the flapper 30 from its second position. As shown, the sleeve locking mechanism 118 is spring loaded. Alternative actuation methods, as known in the art, may be used to activate the sleeve locking mechanism 118 . Additionally, the sleeve locking mechanism 118 may have the ability to reset to its original position, thereby allowing the sleeve 70 to reset to its initial non-shifted position.
[0098] FIG. 11 also depicts a recess 122 in the downhole tool 2 configured to receive the catch mechanism 82 . In one embodiment, the catch mechanism 82 has an undeformed outer diameter that is larger than the inner diameter of the downhole tool 2 . Accordingly, in this embodiment, the inner diameter of the downhole tool 2 constrains the outer diameter of the catch mechanism 82 . By providing a selectively positioned recess 122 in the downhole tool 2 , the catch mechanism 82 is allowed to expand into the recess 122 when the sleeve 70 is in a shifted position. This expansion allows the full inner diameter of the sleeve to be utilized for ball return during flow back operations. In one configuration, the catch mechanism 82 is a spring loaded collet assembly.
[0099] Referring to FIG. 12 , the downhole tool 2 is shown during flow back. As shown, the flapper valve 30 has rotated toward its first position, thereby allowing the drop member 78 to flow up the tubular string from distal portions of the wellbore. Additionally, the catch mechanism 82 has retracted into a recess 122 formed in downhole tool 2 . This retraction allows the full bore of the tubular string to be utilized and prevents the catch mechanism 82 from interfering with the return of the drop members 78 to the surface during flow back. In some configurations, the flapper valve 30 may be locked in its first position during flow back by a latching mechanism. Locking the flapper 30 in its first position would increase the flow up the axial bore 18 of the tubular production string while allowing flow from the stimulated zones to continue through the ports 106 . FIGS. 13-19 depict a downhole tool 126 that is actuated by a pressure activation system according to another embodiment of the present invention. Downhole tools 126 are selectively disposed within stimulation stages according to a predetermined stimulation process. Each downhole tool 126 utilizes a counter to actuate a sliding sleeve. Each counter is associated with a stimulation stage and is preset to a predetermined number. The counter indexes for every drop member 78 that passes through the downhole tool 126 . After the predetermined number is reached, the counter prevents subsequent drop members 78 from passing through the downhole tool 126 to downstream portions of the tubular production string. Accordingly, each drop member 78 that is dropped proceeds to a predetermined stage number. Once at the predetermined stage number, the drop member 78 seats in a catch mechanism and seals the axial bore of the tubular production string. Increased pressure in the tubular production string upstream of the predetermined stage number shifts the predetermined tool 126 and allows access to the subterranean formation through openings in the tubular production string.
[0100] Referring to FIG. 13 , a cross-sectional view of the downhole tool 126 in a pre-shifted position is illustrated. In the pre-shifted position, the downhole tool 126 allows fluid and/or proppant to pass through the downhole tool 126 to the stage being stimulated while restricting access to openings formed in the downhole tool 126 . The downhole tool 126 utilizes a shifting sleeve 130 that may be secured in a pre-shifted position by a shear pin 50 . The shifting sleeve 130 employs a counter assembly 132 to activate shifting of the sleeve 130 . The design of the counter assembly 132 may vary, as will be appreciated by one of skill in the art. As shown in FIG. 13 , the counter assembly 132 includes a counter mechanism 134 , a locking mechanism 138 , a rocker mechanism 142 , a counter spring 146 , and a catch mechanism, such as a protrusion 158 . In at least one embodiment, the counter assembly includes a manual setting mechanism 170 that allows the counter mechanism 134 to be incremented or decremented manually through buttons or levers. In an alternative embodiment, an electronic setting mechanism may be provided that allows an operator to remotely set the counter to a predetermined number. The preset number for the counter mechanism 134 may be revealed in a window 150 constructed of suitable transparent materials, such as Lexan or other similar materials. The window 150 may be viewed either from the sidewall of the pipe or by looking down the tubular before installation.
[0101] FIG. 14 depicts the downhole tool 126 in a shifted position, revealing perforations 154 in the tubular production string. In the shifted position, the downhole tool 126 allows fluid and/or proppant to pass through the perforations 154 while restricting access to downstream portions of the tubular production string. As illustrated in FIG. 14 , the drop member 78 remains lodged in the shifting sleeve 130 and restricts flow that might otherwise pass on to stages that have already been stimulated. After stimulation, the drop member 78 is no longer needed to seal the inner bore of the downhole tool 126 and thus is allowed to flow back to the surface. As shown, a sleeve locking mechanism 118 prevents the shifting sleeve 130 from shifting back into its pre-shift position.
[0102] FIG. 15 illustrates a simplified end view of the downhole tool 126 with a drop member 78 disposed therein. In FIG. 15 , the counter mechanism 134 , the locking mechanism 138 , and the counter spring 146 are not shown for simplicity reasons. As illustrated, the drop member 78 is seated on the protrusion 158 and substantially seals the inner bore of the downhole tool 126 . To prevent sand or other proppants from interfering with the gears of the counter assembly 132 and to ensure adequate lubrication thereof, the counter assembly 132 may be housed in a chamber 162 that is filled with oil or other fluid. A pressure equalization device 166 , such as a pressure regulator, may be used to ensure that the pressure inside the chamber 162 does not drop substantially below the pressure in the tubular production string, thus minimizing the likelihood of contaminants reaching the counter assembly and ensuring proper operation of the counter assembly 132 . The pressure equalization device 166 is in fluidic communication with the chamber 162 and the inner bore of the tubular production string, and isolates the fluid in the chamber 162 from the fluid and proppants in the tubular production string. In at least one embodiment the pressure equalization device is a piston and cylinder. Additionally, a sealing element may be provided between the counter assembly and the inner bore of the tubular string to further isolate the counter assembly 132 from contaminants.
[0103] FIGS. 16-19 illustrate in detail one embodiment of a counter assembly 132 . As shown in FIGS. 16-19 , the counter assembly 132 includes a counter mechanism 134 , a locking mechanism 138 , a rocker mechanism 142 , a counter spring 146 , and a manual setting mechanism 170 . Referring to FIGS. 16-17 , a catch mechanism, such as a protrusion 158 , interconnects with the rocker mechanism 142 . The rocker mechanism 142 interconnects to a counter mechanism 134 , a locking mechanism 138 , and a spring 146 . Upon contact with a drop member, the protrusion 158 rotates the rocker mechanism 142 and allows the drop member to pass through the internal bore of the downhole tool 126 . Upon rotation of the rocker mechanism 142 , the counter mechanism 134 indexes a running count number. Once the running count number reaches a predetermined number, the counter mechanism 134 moves a trip pin 174 which allows the locking mechanism 138 to shift, thereby preventing subsequent drop members from passing through the downhole tool 126 to downstream portions of the tubular string. In some embodiments, the counter mechanism generates an electronic signal to activate the locking mechanism. In these embodiments, once the predetermined number is reached, an electronic signal is sent to the locking mechanism, which shifts into a locked position upon receipt of the signal. In some embodiments, the counter mechanism also may generate an electronic signal to activate shifting of an inner tubular member, such as a sleeve. In these embodiments, the sleeve would not be activated by an internal pressure within the tubular string.
[0104] A manual setting mechanism 170 allows the counter mechanism 134 to be incremented or decremented manually through buttons or levers, thereby allowing the counter mechanism 134 to be preset to a predetermined number. As discussed above, an electronic setting mechanism may be provided that allows an operator to remotely set the counter to a predetermined number. Accordingly, the counter mechanism 134 is settable such that each tool 126 in the tubular production string will have a unique number and will lock out only after the proper numbers of balls have passed by it. The counter assembly 132 also includes a counter spring 146 that interconnects with the rocker mechanism 142 and restrains rotation of the rocker mechanism 142 . The counter spring 146 is configured to prevent the counter assembly 132 from counting when fracing fluid with or without proppant is passed through the downhole tool under typical fracing conditions. Accordingly, the counter spring 146 ensures that the rocker mechanism 142 will rotate only under the force of a drop member 78 seated on the catch mechanism. The counter spring 146 is illustrated as a linear spring; however, in some embodiments the counter spring 146 may be a torsion spring disposed on the shaft of the rocker mechanism 142 .
[0105] As depicted in FIGS. 16-17 , the counter assembly 132 incorporates a plurality of gears 178 and a plurality of counter wheels 180 to enable counting to a predetermined number, which in turn facilitates engagement of the locking mechanism 138 . The counter mechanism 134 may incorporate geneva gears or other incrementing/decrementing gears to facilitate proper counting. For example, the device may have a gear for 1's, 10's and 100's places and may use geneva gears or other incrementing gears to facilitate proper counting between these places.
[0106] As previously mentioned, the design of the counter assembly 132 may vary without departing from the scope of present disclosure. For example, in one embodiment, the counter is a disk that rotates to release the ball. In another embodiment, a button or section of the wall may move in the radial direction to allow the ball to pass and decrement the counter. As a further example, instead of utilizing a catch mechanism interconnected with a rocker mechanism 142 , the catch mechanism could translate in and out of the inner bore of the tubular production string to actuate a click counter. In this configuration, the motion of the protrusion 158 would be orthogonal to the central axis of the tubular production string. The orthogonal motion would actuate the counter mechanism 134 in a similar fashion as a hand-held clicker. Once the predetermined number is reached, the counter mechanism 134 would activate the locking mechanism 138 to prevent orthogonal movement of the protrusion. In this example, the protrusion 158 may have sloped surfaces to enable a drop member to force the protrusion 158 into the chamber 162 and to pass by the protrusion 158 .
[0107] FIGS. 18-19 depict an embodiment of the locking mechanism 138 . In FIGS. 18-19 , a trip pin 174 is disposed toward a lower, or downstream, end of the downhole tool 126 . Accordingly, during normal flow, the direction of fluid flow is from left to right in FIGS. 18-19 . Referring to FIG. 18 , the locking mechanism 138 is in a clockwise lock position. As illustrated, a sliding lock 186 prevents an inner shaft 182 of the rocker mechanism 142 from rotating clockwise, but allows the inner shaft 182 to rotate counterclockwise. A compression spring 62 biases the sliding lock 186 against a trip pin 174 and is disposed between the sliding lock 186 and an anchor 190 that is interconnected with the sleeve 130 . As shown in FIG. 17 , the trip pin 174 is interconnected with the counter mechanism 134 . Once a predetermined number of drop members passes by the counter assembly 132 , the counter mechanism 134 pulls the pin 174 . Accordingly, in the clockwise lock position, the locking mechanism 138 allows drop members, such as balls, to pass by the counter assembly 132 to distal portions of the tubular production string. However, the locking mechanism 138 prevents drop members from passing by the counter assembly 132 in a reverse direction toward the surface.
[0108] Referring to FIG. 19 , the trip pin 174 has been pulled by the counter mechanism 134 . As shown, the compression spring 62 has shifted the sliding lock 186 into a counterclockwise lock position. In this position, the sliding lock 186 prevents the inner shaft 182 from rotating counterclockwise, but allows the inner shaft to rotate clockwise. The compression spring 62 maintains the sliding lock 186 in this counterclockwise lock position. By preventing counterclockwise rotation, the lock mechanism 138 prevents drop members from passing to downstream portions of the tubular production string. Thus, once the lock mechanism 138 is in this lock position, a subsequent drop member will seat on the protrusion 158 and substantially seal the inner bore of the tubular production string. Internal pressure will build in the inner bore of the tubular production string, thus shifting the sleeve 130 associated with the counterclockwise locked counter assembly 132 into a shifted position. Accordingly, in the counterclockwise lock position, the locking mechanism 138 allows drop members, such as balls, to pass by the counter assembly 132 toward the surface. However, the locking mechanism 138 prevents drop members from passing by the counter assembly 132 to distal portions of the tubular production string.
[0109] FIGS. 20-21 depict a counter assembly according to another embodiment of the present invention wherein the counter assembly utilizes a button or section of the sleeve wall to allow a ball to pass and decrement the counter. In general, FIGS. 20-21 illustrate a linear actuation method of incrementing/decrementing a counter. Referring to FIGS. 20-21 , treatment fluid 192 is flowing toward distal portions of the tubular string. A button 194 has sloped surfaces and extends into an internal bore of a sleeve 130 . The button 194 is interconnected to a rack 196 , which is configured to intermesh with a gear 198 to increment/decrement a counter. The gear 198 may be, for example, a counter gear or a worm gear that is interconnected with a counter mechanism. A sliding lock 186 is interconnected with a spring 62 , an anchor 190 , and is in mechanical or electrical communication with a counter mechanism. Once a predetermined number of balls have passed by the button 194 , the counter mechanism will activate the sliding lock 186 to prevent subsequent balls from passing by the button 194 . As shown in FIG. 20 , a drop member 78 has contacted the button 194 . The sliding lock 186 is not engaged, and thus the ball may depress the button in a direction orthogonal to the fluid flow 192 and continue flowing toward distal portions of the tubular string. Referring to FIG. 21 , the drop member 78 has depressed the button 194 into the body of the sleeve 130 , and the rack 196 has engaged the gear 198 , thereby causing the gear 198 to rotate. The rotation of the gear 198 causes the counter mechanism to increment/decrement the running count number.
[0110] According to at least one embodiment of the present invention, a method is provided that selectively stimulates stages using a single-sized ball. Following the stimulation of a stage, a ball is dropped into the well and pumped down the center of the tubular production string. The ball passes through each downhole tool 126 in the system under the force of the fluid pressure. Because of the diameter of the inner bore of the tubular production string, the ball may pass through a downhole tool 126 only if it decrements a counter. In one embodiment, the counter is a disk that rotates to release the ball. In another embodiment, a button or section of the wall may move in the radial direction to allow the ball to pass and decrement the counter. When the counter reaches zero, a lock is engaged and the counter will no longer allow the ball to pass through the downhole tool 126 . With the ball prevented from passing, the flow through the tubular is greatly restricted and a pressure differential will be created. This pressure differential will create sufficient force to move the sleeve from a non-shifted position to a shifted position. The downhole tool may or may not incorporate shear pins to ensure that the sleeve only shifts when a predetermined force is applied. In the shifted position, the ball remains held by the locked counter and provides sufficient flow restriction to divert the bulk of the flow to radial openings in the tubular production string and for the stage to be fraced. Alternatively, the shifting mechanism may activate a flapper device to seal the axial bore of the tubular production string.
[0111] While in the non-shifted position, the downhole tool 126 will not allow balls to pass in the reverse direction. However, fluid will be allowed to pass by the ball relatively unimpeded because of the design of the tubular region. This feature allows the completions engineers to flow back in the event of a screen-out, but not accidently flow back beyond the next downhole tool. If this were to happen each ball would then decrement the counter as soon as fracing operations resumed and the sleeves would shift too soon. By preventing the ball from returning while in the downhole tool is in a non-shifted position, counting integrity is preserved. While in the shifted position, the reverse flow lock is removed and the downhole tool will allow relatively unrestricted flow of the balls through the downhole tool 126 .
[0112] The axial bore of the downhole tool may also allow passage of solid elements, such as wireline tools, tubing, coiled tubing conveyed tools, cementing plugs, balls, darts, and any other elements known in the art. When all of the stages have been fraced, the pressure is reduced and the flow reverses direction. In this flow back mode, the balls will pass back by the counter with very little resistance.
[0113] FIGS. 22-23 illustrate another embodiment wherein the flapper valve 30 is used as a whipstock slide. According to this embodiment, the flapper valve 30 is longer in one axis than in another, such that the flapper valve 30 forms a slide when in the second position. The angled flapper valve 30 assists the placement and extraction of tools through the lateral bore 22 of the downhole tool 2 . It is feasible that the lateral bore 22 of the downhole tool 2 may be filled with a fill material 206 , such as soft cast iron, cement, etc. that may need to be removed with a drilling apparatus or by chemical treatment. Additionally, an orienting key may be associated with the flapper valve 30 to orient and guide tools to the lateral bore 22 of the downhole tool 2 . In some embodiments, the orienting key is a separate member that is landed in a crowsfoot associated with the flapper valve 30 . The flapper valve 30 is restrained in its first position by a sleeve 34 , which is held in place by shear pins 50 . The flapper valve 30 may be held in place by other mechanisms described herein.
[0114] Referring to FIG. 23 , the sleeve 34 has been displaced vertically within the tubular string 14 by a shifting tool thereby allowing the flapper valve 30 to move from its first position to its second position. The shifting tool may be operated by wireline, slickline, coiled tubing, or jointed pipe as appreciated by one skilled in the art. A hinge 58 interconnects the lower end of the flapper valve 30 to the downhole tool and allows the flapper valve 30 to rotate. A torsion spring 58 biases the flapper valve 30 towards its second position. Another spring 62 may be provided to assist the movement of the flapper valve 30 from its first position to its second position.
[0115] FIGS. 24-28 illustrate yet another embodiment wherein a downhole tool 2 is utilized to prevent a well blowout. According to this embodiment, an inner tubular member 210 is operably interconnected to the axial bore of the downhole tool 2 by shear pins 50 or other connecting means known in the art. Additionally, a sealing element 214 may be placed around the inner tubular member 210 to provide a seal between the inner tubular member 210 and the downhole tool 2 . The sealing element 214 may be elastomeric, plastic, metallic, or any other sealing elements known to one of ordinary skill in the art. The inner tubular member 210 restricts the movement of the flapper valve 30 and holds the flapper valve 30 in its first position. The upper portion of the inner tubular member 210 forms a chamber that houses a ball 218 . The chamber is also defined by a ball seat 222 and a ball cage 226 .
[0116] FIG. 24 shows a condition where fluid is flowing down the tubular string 14 . As shown, the fluid flows into the inner bore of the downhole tool 2 and further into the inner tubular member 210 via a ball seat 222 and orifices 230 . The fluid flow and pressure forces the ball 218 to contact the ball cage 226 , which prevents the ball 218 from moving distally into the tubular string 14 . As illustrated, fluid flows around the ball 218 without unduly restricting the fluid flow. In this embodiment, the inner tubular member 210 is held in place within the downhole tool 2 by shear pins 50 . The annulus formed between the inner tubular member 210 and the downhole tool 2 is sealed by an o-ring 214 or other sealing elements commonly used in the art. As shown in FIGS. 24-25 , three sets of vertically displaced shear pins 50 and o-rings 214 are utilized. As will be appreciated by one of skill in the art, the number of shear pins and sealing elements may vary.
[0117] Referring to FIG. 25 , as fluid flows up the internal bore of the tubular string 14 , it enters the downhole tool 2 and the inner bore of the inner tubular member 210 . The fluid flow and pressure causes the ball 218 to seat in the ball seat 222 , thus restricting the fluid flow through the inner tubular member 210 by redirecting the fluid flow through orifices 230 in the inner tubular member 210 .
[0118] FIG. 26 shows an increased fluid flow associated by a well blowout that is represented by the dark arrows. The increased fluid flow flows through the orifices 230 , but in a restricted manner, which creates an upward force on the inner tubular member 210 .
[0119] In FIG. 27 , the increased fluid flow caused by the well blowout has sheared the shear pins 50 and thus the inner tubular member 210 has shifted upward in the downhole tool 2 . The upward movement frees the distal flapper valve 30 , which allows it to close the axial bore of the downhole tool 2 . The momentum of the fluid flow and the inner tubular member 210 causes the inner tubular member 210 to continue moving up the tubular string 14 , thus allowing a second proximal flapper valve 30 to close. The flapper valves 30 prevent fluid from flowing up the axial bore of the downhole tool 2 , thereby preventing the well blowout. As will be appreciated by one of skill in the art, more or less than two flapper valves 30 may be used without departing from the scope of the invention.
[0120] FIGS. 29-32 illustrate a downhole tool 2 actuated by a drop member and catch/release mechanism 250 according to yet another embodiment of the invention. The downhole tool 2 allows access to the annulus of a tubular string placed in a wellbore via a unique valve with two stationary positions with separate bores. One bore of the valve is open to the interior of the tubular to which the valve is attached; the second bore may create a passageway to the annulus of the tubular string by use of a drop member. The inner tubular, when in the initial or first position, has sealing elements (e.g. elastomeric, plastic, metallic) that seal the space between the inner and outer tubular members. The seal allows fluids, such as drilling mud, cement, and fracturing fluids, to be effectively pumped through the bore of the tool with minimal or no leakage to the annulus. The sealing may be enhanced by use of elastomers, O-rings, softer metals or other techniques customary in downhole tools. The tool may also be constructed of metallic or non-metallic materials, such as the composite materials currently used in composite downhole tools. In one embodiment, the tool 2 is connected to the tubular string 14 by a threaded connection.
[0121] The downhole tool 2 comprises an inner tubular member 210 , outer tubular member 212 , catch/release mechanism 250 , locking mechanism 260 and locking dog 270 . The downhole tool 2 is positioned such that the outer tubular member aligns with fracture ports 26 . Inner tubular member 210 is slidable relative to outer tubular member 212 . Stated another way, inner tubular member 210 may be actuated relative to outer tubular member 212 . The inner tubular member 210 engages with piston 240 . As the inner tubular member 210 moves downward, or distally, relative to outer tubular member 212 , the piston 240 compresses the spring 90 in communication with the upper reservoir 94 and the lower reservoir 98 . The catch/release mechanism 250 comprises collet fingers 252 and is dimensioned with major inner diameter 254 and minor inner diameter 256 . The ball 218 moves through axial bore 18 as a result of differential pressure on the upstream and downstream pressure on the back to engage the catch/release mechanism 250 .
[0122] As will be discussed below, depending on the pressure applied within the axial bore 18 , the ball 218 may engage the catch/release mechanism 250 until the catch/release mechanism 250 moves distally, or downwards, within axial bore 18 so as to engage locking mechanism 260 , or alternatively, may momentarily engage catch/release mechanism 250 without catch/release mechanism 250 engaging locking mechanism 250 . Such alternatives allow the ball 218 to either draw the inner tubular member 210 distally or downward so as to create an opening 26 to axial bore 18 , or instead pass through catch/release mechanism 250 without creating such an opening. Thus the internal pressure within the axial bone can be used to selectively open the fracture ports 26 to allow fluid communication to the annulus of the wellbore.
[0123] Referring to FIGS. 29A-C , a downhole tool 2 interconnected to a tubular string 14 within a wellbore is depicted. The downhole tool 2 is shown in an unactuated state under a low axial bore pressure. FIG. 29A is a cross-sectional view of the downhole tool 2 , FIG. 29B is a cross-sectional top view of section A-A of the catch/release mechanism 250 of the embodiment of FIG. 29A , and FIG. 29C is a detailed cross-sectional side view of portion A of the catch/release mechanism 250 of the embodiment of FIG. 29A . In the configuration of FIGS. 29A-C , the downhole tool 2 has been positioned in a tubular string 14 , a ball 218 pumped into the axial bore 18 , with a generally pre-determined lower pressure 86 applied. The drop member ball 14 descends distally within axial bore 18 toward catch/release mechanism 250 . The inner tubular member 210 does not appreciably move relative to the outer tubular member 212 and remains in an unactuated state (deemed position one or a first position). As the ball 218 descends within the axial bore 18 , the ball 218 engages and lands in the catch/release mechanism 250 at collet fingers 252 and draws both catch/release mechanism 250 downward and inner tubular member 210 downward, until catch/release mechanism 250 engages locking mechanism 260 as depicted in FIGS. 30A-B . The wellbore is thus sealed above the drop member ball 218 from the distal portions of the wellbore. It is important to note that under lower pressure 86 , ball 218 engages collet fingers 252 and pulls catch/release mechanism 250 downward, without axially-spreading collet fingers enough to effect passing through collet fingers 252 .
[0124] When the lower pressure 86 is held in wellbore, it is below that necessary for the drop member ball 218 to disengage from and pass through the tool 2 to travel to any subsequent tool 2 distal from the first tool. The drop member ball 218 , when held in the tool at the lower pressure 86 , causes the inner tubular member 210 to move from a first position to a second position over a period of time, in a similar manner to the activation cylinder of a hydraulic jar. The activation cylinder, comprising an upper reservoir 94 and lower reservoir 98 of hydraulic oil or similar fluid, bleeds through a fluid communication means, such as a connecting aperture or around the activation cylinder, to allow the cylinder to move over a period of time from the first position to the second position, allowing the inner tubular member 210 to move from the initial (first, unactuated) position to the second (actuated) position.
[0125] FIG. 30A is a cross-sectional view of the downhole tool shown in FIG. 29A in an actuated state under a low axial bore pressure and FIG. 30B is a detailed cross-sectional side view of portion A of the downhole tool of FIG. 30A . As depicted in FIGS. 30A-B , the inner tubular member 210 has moved downward or distally so as to create an aperture in tubular string 14 at fracture ports 26 , thereby enabling stimulation fluid 38 to flow from axial bore 18 into a hydrocarbon formation adjacent fracture ports 26 . That is, the wellbore is open to the annulus of the tool 2 . Furthermore, inner tubular member 210 has moved downward or distally so as to activate locking dogs 270 , thereby preventing the inner tubular member 210 from moving upwards or proximally up tubular string 14 and closing fracture ports 26 . Locking dogs 270 have an unactuated profile within the inner tubular member 210 . One example of locking dogs known to those skilled in the art, is provided in U.S. Pat. No. 4,437,55 to Krause, Jr., which is hereby incorporated by reference in its entirety. In this configuration (i.e. when an aperture or flow channel has been created at fracture ports 26 so as to allow stimulation fluid 38 egress from axial bore 18 ), the inner tubular member 210 is in an actuated state deemed position two or a second position.
[0126] Note that the further downward movement of the inner tubular member 210 from the second position, and passing of the drop member ball 218 , will be prevented given the change in profile of the stationary portion of the tool 2 . That is, the application of a higher pressure within axial bore 18 with the drop ball 218 in place will not cause the drop ball 218 to pass, since the change in profile as provided by the wedge shaped locking mechanism 260 will prevent the radial deformation of the collet fingers 252 and therefore prevent the passing of the drop member ball 218 . In fact, a higher pressure will cause the collet fingers 252 with the trapped drop member ball 218 to more tightly wedge into the change in profile. Note that inner diameter 256 of catch/release mechanism 250 is smaller than ball 218 diameter, thus prevents the drop ball 218 from traveling downhole from the wedge shaped locking mechanism 260 .
[0127] The tool 2 has an internal bore that allows wellbore fluid to be pumped through the tool 2 , and also may allow physical passage of solid elements, such as wireline or slickline tools, tubing and coiled tubing conveyed tools, and drop elements, such as cementing plugs, balls and darts, which can pass through the tool when the tool is in the initial closed position. When the tool 2 is in the second (actuated) position, the bore of the tubing is effectively sealed, and fluid pumped into the wellbore is directed to the annulus of the tubular string, through the bore previously closed by the inner tubular member 210 . If the device 2 is used with external tubular packers, such as external casing packers, swellable packers or similar devices, it is not anticipated that cement will be on the external portion of the tool. If cement is contemplated to be placed around the tool 2 and hardened, it may be necessary to place an external cover, outside of the tool 2 in the initial position, to prevent the cement from interfering with the movement of the inner tubular member 210 to the second position. Such an external cover would be removed or deformed by the fluid pumped through the second bore. It also may be desired to pump acid or other fluid (including abrasive particle laden fluids) through the opening created by the movement of the inner tubular member 210 to the second position to remove debris and/or the cement from the annulus and improve a fracturing operation.
[0128] If the tool 2 is activated with drop members from the surface as described above, it may be desirable to have a multi-pressure activation system. For example if the tool is to be deployed in a horizontal well that is to be fracture stimulated with multiple stages (See FIG. 5 ), using multiple tools that are connected to and part of the tubular string in the wellbore, it would be desirable to have a tool that would be actuated by an applied first pressure exerted at the surface of the wellbore when the drop member lands and seals in the tool and have a second pressure at which the drop member passes through that tool without actuation, and continues to pass through each tool set distally in the wellbore until the desired tool is reached, and which would be selectively activated to allow a fracture stimulation to be pumped into the annulus of the tubular at a pre-determined location, as described below.
[0129] When a sufficiently higher pressure 74 (relative to the lower pressure 86 described above) is applied to the downhole tool 2 and a ball 218 inserted into axial bore 18 , the downhole tool 2 operates in an alternative manner, as depicted in FIGS. 31A-D . FIG. 31A is a cross-sectional view of the downhole tool shown in FIG. 29A yet under a high axial bore pressure. FIG. 31B is a cross-sectional top view of section A-A of the downhole tool of FIG. 31A , FIG. 31C is a detailed cross-sectional side view of portion A of the downhole tool of FIG. 31A , and FIG. 31D is a cross-sectional view of the downhole tool of FIG. 31A under a high axial bore pressure after passage of the ball drop member.
[0130] In the configuration depicted in FIGS. 31A-C , the downhole tool 2 has been positioned in a tubular string 14 , a ball 218 inserted into the axial bore 18 , and a higher internal wellbore pressure 74 applied. A ball 218 has descended distally within the axial bore 18 toward the catch/release mechanism 250 . The inner tubular member 210 has slightly moved relative to the outer tubular member 212 , although not enough to open fracture port 26 . Under the higher internal wellbore pressure 74 , the ball 218 has engaged the catch/release mechanism 250 at collet fingers 252 and slightly drawn both the catch/release mechanism 250 and the inner tubular member 210 downward. However, in contrast to the operation of the downhole tool 2 under the lower pressure 86 operation as discussed above, under the higher internal wellbore pressure 74 the ball 218 engages collet fingers 252 and, while pulling catch/release mechanism 250 downward (and with it inner tubular member 210 ), the ball 218 axially-spreads collet fingers enough so as to pass through collet fingers 252 . FIG. 31C depicts the ball 218 under high pressure 74 as collet fingers 210 spread, such that the inner diameter 256 of the catch/release mechanism 250 is equal to the ball 218 diameter. FIG. 31D depicts downhole tool 2 after ball 218 , under high pressure 74 , has passed through catch/release mechanism 250 . In this state, the inner tubular member 210 , as engaged with piston 240 and actuation cylinder, is urged vertically upwards by spring force 92 so as to return to its first (unactuated) state. The actuation cylinder, and thus the inner tubular member 210 , is returned to the initial first position by any stored energy device including a spring 90 , stored hydraulic energy, etc. Note that a ball 218 which passes through tool 2 as described herein may subsequently travel through tubular string to another tool 2 or to the distal portion of the wellbore as necessary to complete the wellbore operation.
[0131] The spring 90 and actuation cylinder also function to prevent premature deployment of the tool 2 resulting from the friction of fluid being pumped through the tool 2 and resulting higher wellbore pressure. Other embodiments employ alternative means to allow controlled passing of a drop ball 218 , to include collet slidable devices (e.g. U.S. Pat. Nos. 5,244,044, 4,729,432, 7,373,974, each incorporated by reference in their entirety), collet deformable fingers such as those described above (and also, e.g. U.S. Pat. Nos. 4,893,678, 4,823,882, 4,292,988, each incorporated by reference in their entirety) and other ball release mechanisms known to those skilled in the art.
[0132] In another embodiment, the tool 2 could be configured to allow the return of drop members to the surface by placing an inclined surface on the distal portion of the inner tubular member 210 , allowing the drop members to move from tools deployed in the distal portions of the wellbore, back through the tools and returning to the surface. This would be accomplished in a similar manner to the drop members passing tools during stimulation operations, but in the opposite direction. The drop member would contact the inner tubular assembly from the distal end, and push the inner tubular assembly a small distance to engage the locking dogs. This small axial movement will allow the radial deformation of the collet fingers by a buildup of pressure on the drop member from the formations previously stimulated. The drop members could be composed fully or partially of a dissolvable material, such as described in U.S. Patent Appl. Publ. No. 2011/0132621, which is hereby incorporated by reference in its entirety, using nanotechnology, or other materials, such as a magnesium alloy, that will either result in the total dissolution of the drop member or cause a reduction in the ball size to allow the drop members to pass through the tools and back to the wellhead.
[0133] Once a ball 218 has passed through downhole tool 2 via catch/release mechanism 250 , it may be returned as depicted in FIGS. 32A-B . FIG. 32A is a cross-sectional view of a downhole tool in an unactuated state under a high axial bore pressure during retrieval of the drop member, and FIG. 32B is a detailed cross-sectional elevation view of portion A of the downhole tool shown in FIG. 32A . To return ball 218 , a high internal wellbore pressure 74 is provided to axial bore 18 such that ball 218 engages the far or distal side of collet fingers 210 , as shown by ball position 218 A . With enough internal wellbore pressure the ball 218 will spread collet fingers 210 as depicted in FIG. 32B so as to allow passage vertically up the axial bore 18 of the tubing string, as shown by ball 218 at ball position 218 B . Note that although ball 218 is returned, inner tubular member 212 remains actuated, as depicted in FIG. 32A , because of extended locking dogs 270 . Should the locking dogs 270 be configured for remote actuation or deactuation, the locking dogs 270 could be retracted, in which case inner tubular member 270 would ascend vertically or proximally so as to close fracture ports 26 .
[0134] In one embodiment, the drop ball 218 is other than substantially round. For example, the drop ball 218 may be oblong spherical, bullet shaped, conical shaped, egg-shaped, or any shape that enables the functions herein described.
[0135] Conventional drop members, such as non-metallic frac balls may also have a reduction in size due to the erosive nature of the wellbore fluids being produced through the tool. Even if the frac ball does not open the collet fingers fully to allow the full sized ball to pass and be recovered at the surface, it will cause some radial movement of the fingers, opening a small aperture that will pass wellbore fluid at high velocity. It is well known to one of ordinary skill in the art that small apertures leaking high velocity fluids may quickly become eroded and using a relatively soft non-metallic frac ball will enhance this phenomena to erode the outer diameter of the frac ball, to allow passage through the tool.
[0136] Another method to handle the balls during flowback and production would be to extend several of the collet fingers, but not all, so that the balls would be prevented from plugging the tool during production, and that there would be significant flow area around the ball through the spaces of the collet fingers that were not extended, such that all production would bypass the ball and not cause a production shortfall due to plugging of the tools by the balls during flowback and production. Another means to return a ball include the use of a ball with a dissolvable outer layer which dissolves over time to create a smaller diameter ball which may pass through a catch/release mechanism.
[0137] While various embodiments of the present invention have been described in detail, it is apparent that modifications and alterations of those embodiments will occur to those skilled in the art. Moreover, references made herein to “the present invention” or aspects thereof should be understood to mean certain embodiments of the present invention and should not necessarily be construed as limiting all embodiments to a particular description. However, it is to be expressly understood that modifications and alterations are within the scope and spirit of the present invention, as set forth in the following claims. | A downhole tool is provided that selectively opens and closes an axial/lateral bore of a tubular string positioned in a wellbore used to produce hydrocarbons or other fluids. When integrated into a tubular string, the downhole tool allows individual producing zones within a wellbore to be isolated between stimulation stages while simultaneously allowing a selected formation to be accessed. The downhole tools and methods can be used in vertical or directional wells, and additionally in cased or open-hole wellbores. | 4 |
FIELD OF THE INVENTION
[0001] This invention relates generally to the field of ventilation and more particularly to ventilation of residential and commercial living spaces. Fresh air is needed for the comfort and health of building occupants. Most particularly this invention relates to air to air heat exchangers of the type which may be used to transfer heat and energy from an exhaust air stream being expelled from a building into a fresh air stream being drawn into the building to replace the stale air being exhausted from the building.
BACKGROUND OF THE INVENTION
[0002] Ventilation of building's occupied by humans is required. Such ventilation is required to provide fresh oxygen to the occupants of the building and to remove stale air with high concentrations of CO 2 for health and comfort reasons. Modern construction and building codes have imposed certain requirements on building ventilation systems. In particular modern construction focuses on heavily insulated and air tight buildings to reduce overall energy consumption. Making the building substantially airtight limits the amount of energy loss through drafts and the like.
[0003] On the other hand, modern building codes require a sufficient turnover of air within a dwelling in order to provide sufficient fresh air and oxygen for the occupants to be healthy and comfortable. Certain technology and equipment have been developed to meet with these competing demands. In particular, specialized ventilation units have been developed to provide a source of fresh air while at the same time limiting the amount of energy lost through the exhaust airstream.
[0004] Such devices are called heat recovery or energy recovery ventilation units and may be referred to in northern climates as HRVs. In southern climates they are referred to as energy recovery ventilation devices or ERVs. Essentially, the only difference between these two units is that an HRV captures heat energy from the exhaust airstream, whereas an ERV reduces a cooling load imposed by the fresh air stream.
[0005] Typically, these devices comprise a body containing an air to air heat exchanger. The exhaust airstream is passed through one side of the heat exchanger while the fresh air stream is passed through the other side of the heat exchanger. In this way the airstreams are allowed to exchange energy by means of a counter current heat exchange, without the airstreams being in direct contact or being allowed to mix with one another. Thus the quality of the fresh air is preserved.
[0006] Again typically, HRV and ERV devices include small fans to drive the air through the heat exchanger. Ideally the flow of fresh air into the building should be equally matched by the flow of stale air being exhausted out of the building. Although the fans can be calibrated in a factory setting to a predetermined flow rate, site-specific installation parameters can affect the aerodynamic head for the inflow and outflow lines and thus volumetric performance of the fans.
[0007] As a result there is understood to be a need to balance the airflow streams manually for each ERV/HRV installation for example through the use of manually adjustable dampers that restrict the airflow through the conduits leading to the fans. This balancing is accomplished by means of a skilled technician using small airflow measurement devices called pitot tubes, which may be temporarily installed on the respective airstreams to measure and calibrate the incoming and outgoing airflows. Then the airflow through an individual fan can be site adjusted by a technician by adjusting dampers until the visual inspection of the pitot tubes reveals a balanced airflow across the ERV/HRV for that specific location at that specific time.
[0008] Unfortunately, this airflow balancing adjustment requires considerable time from the technician and there is no easy way for a building occupant to be able to tell if it is been done correctly, or indeed, if at all. In some cases this balancing step may be skipped by the installer to save money. In other cases changes to the airflow system or in air pressure can affect the balancing and so what might have been balanced at one point can get out of balance. Further there is a tendency for the fan characteristics to change over time, due to changes in the lubrication and wear on the mechanical parts, or even an accidental change to the baffle position during routine maintenance or the like of the unit. In most cases the units will include removable filters which require periodic cleaning meaning that the unit is opened and the sensitive elements, such as the baffles, are exposed. None of these potential unbalancing changes can be accurately detected without a return of the technician and a recalibration of the system by means of the pitot tube measurements. Therefore there is a need for an improved way of balancing the air flows through ERVs and HRVs.
[0009] Examples exist in the prior art that attempt to improve airflow balancing in these types of ventilation units. For example, U.S. Pat. No. 7,458,228, is directed to some of these issues. However in this device a single motor is used to drive two fans. Adjustment of the airflow is accomplished by means of movable dampers which restrict the air flow by closing one or the other the air flow pathway to a certain extent. This patent teaches that balancing is achieved by determining the first static pressure difference in the fresh air path by using first and second static pressure sampling locations and then determining a second static pressure difference in the exhaust air path using third and fourth static pressure sampling locations comparing the predetermined exhaust air flow value corresponding to the first static pressure difference with a predetermined exhaust air flow value corresponding to that second static pressure difference to determine if a predetermined fresh air and exhaust air flow values are at least substantially equal. Again, this invention requires the use and installation of pitot tubes, and manual adjustment of fan dampers. Further, this system cannot adjust to changes in the airflows over time, without some intervention of a skilled technician.
[0010] Other examples of prior disclosures which address the issue of balancing air flows include U.S. Pat. Nos. 6,289,974; 7,007,740; 7,458,228; 7,656,942; 7,795,827; and U.S. Publication Application Nos., 2001/0030036A1; and 2002/0017107 A17. While interesting, none of these prior devices overcome the issue of requiring a manual measurement and then manual adjustment of for example movable dampers for the airflow to be balanced across the ventilation units. Thus, none of these prior disclosures overcome the issue of requiring a re-attendance of a skilled technician to deal with any changes that might occur to the airflows over time.
SUMMARY OF THE INVENTION
[0011] What is desired is a simple and easy to use HRV and/or ERV unit that can reliably maintain a balanced airflow between the fresh air and the exhaust air without requiring manual measurement, visual inspection of gauges or pitot tubes, manual adjustments of dampers or the like, and most preferably does not require the services of a skilled and expensive technician for each and every installation. Such a device should provide a balanced airflow under all conditions regardless of site specific aerodynamic issues and should be able to maintain such a balanced airflow in light of changed conditions either by reasons of a change to the site-specific ventilation ducting configuration, which can change the aerodynamic head, changes in air pressure, changes in fan motor characteristics due to mechanical wear or for any other reason. As well such a device should preferably provide to the occupants a reliable indication that the air flows through the device are both appropriate for the occupants' air-quality concerns and that inflows and outflows are balanced. It is further desirable for the device to render the air flows through the device adjustable to suit varying occupancy levels. For example, it is desirable to be able to reduce the airflow when a dwelling is unoccupied and there is less need for fresh air to conserve energy. At the same time a minimum airflow may be required to for example control humidity or the like.
[0012] The present invention addresses the foregoing issues through the use of a ventilation device with automatic air flow rebalancing. According to the present invention air flow sensors can be used which produce a signal proportional to a volume of air flowing past the sensor. These signals can be generated for each of the fresh air inflow and exhaust air outflow across the heat exchanger. By comparing the two signals the present invention enables a controller to monitor and adjust the individual fan speeds to achieve a dynamic and if desired relatively continuous balancing of the air flows.
[0013] The invention comprehends using air flow diffusers, in the vicinity of the sensors, to assist in developing a laminar air flow stream past the sensors. Laminar air flow is more reliably measurable than is turbulent air flow. The invention also comprehends using identically sized cross-sectional flow areas in the vicinity of the inflow and outflow sensors, to permit the sensors readings to be easily equated, although using different areas with an appropriate area calibration factor is also comprehended, if less preferred
[0014] Therefore according to a first aspect of the present invention there is provided a heat and energy recovery ventilation unit for a building, said building having an inside and an outside, said unit comprising:
[0015] A main body having a fresh air inlet and an indoor air outlet on one side and a fresh air outlet and an indoor air inlet on the other side and having an air to air heat exchanger within said main body and connected to each of said inlets and outlets to define respective air flow passageways for each of said indoor air and said fresh air, said heat exchanger permitting heat and energy exchange between said indoor air and said fresh air;
[0016] A first variable speed blower for causing said indoor air to pass through said heat exchanger to said outside;
[0017] A second variable speed blower for causing said fresh air to pass through said heat exchanger to said inside;
[0018] At least one electronic air flow sensor to measure at least one of said indoor air flow and said fresh air flow, said air flow sensor producing a data signal related to said measured air flow; and
[0019] A controller for receiving said data signal, said controller using said data signal to control at least one of said variable speed blowers to provide a balanced fresh air inflow and indoor air outflow through said heat recovery ventilation unit.
[0020] According to another aspect of the invention there is provided a method of operating a heat and energy recovery ventilation unit comprising the steps of:
a. Using a first airflow sensor to indicate an air flow through said unit in a first direction; b. Using a second airflow sensor to indicate an airflow through said unit in a second direction; c. Communicating said indicated air flows to a controller, d. Comparing said indicated air flows and determining if a difference exists between the indicated air flows and e. Sending motor control signals to at least one blower motor to change the speed of the blower to reduce said determined difference.
BRIEF DESCRIPTION OF THE DRAWINGS
[0026] Reference will now be made by way of example only to preferred embodiments of the present invention with reference to the attached figures in which:
[0027] FIG. 1 shows a ventilation device according to the present invention installed in the building with ducting connecting the device to both the outside fresh air source and an inside exhaust air source;
[0028] FIG. 2 shows a close-up of the ventilation device of FIG. 1 from above with a cover removed;
[0029] FIG. 3 shows a side view of a diffuser according to the present invention;
[0030] FIG. 4 shows a remote control wall unit with display according to the present invention;
[0031] FIG. 5 shows a view of the unit showing a tilted core housing and associated drain;
[0032] FIG. 6 shows a schematic layout according to the present invention;
[0033] FIG. 7A shows a side cutaway view of an embodiment of a wall box exhaust according to the present invention;
[0034] FIG. 7B shows a side cutaway view of an embodiment of a wall box intake according to the present invention;
[0035] FIG. 8A shows a front view of a timer switch according to the present invention; and
[0036] FIG. 8B shows a side view of the timer switch of FIG. 8A .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0037] FIG. 1 shows a heat energy recovery ventilation unit 10 installed in the building 12 . In the present specification the term building means any structure with living quarters that requires fresh air turn over. Thus the term building comprehends single or multiple family dwellings such houses, duplexes, apartments in high rise buildings, condominium units, row houses and any other enclosed living or occupation space that requires an inflow of fresh air and an exhaust of stale air to meet the needs of living breathing occupants.
[0038] The unit 10 may be installed in a basement 14 , for example, and includes ducting leading up to and away from the unit 10 . The unit 10 is sized and shaped to be installed in either a vertical orientation or a horizontal orientation. Good results have been achieved with an overall size of about 27¾ inches in width, about 21 inches in depth and about 9 inches in height, and having a total weight of between 50 and 60 pounds, most preferably about 55 pounds.
[0039] The ducting 16 begins with inflow air registers 18 located in rooms 20 and 22 and includes ducting 23 which directs stale air towards the unit 10 . The ducting 24 carries fresh air from the unit 10 and distributes it into rooms 26 , 28 , 30 and 32 for example through fresh air registers 27 , 29 , 31 , and 33 . It will be understood by those skilled in the art that the configuration of the ducting 23 , 24 can be easily altered without departing from the scope of this invention. All that is required is to provide a flow path within the building 12 to supply the amount of fresh air that is stipulated in the local building code and to distribute the fresh air into the building in an acceptable way while also providing a flow path within the building 12 to collect and remove stale air.
[0040] Leading away from the unit 10 towards an exterior wall 34 is further ducting 36 and 38 . The ducting 38 carries fresh air from the outside 40 to the unit 10 . The ducting 36 carries stale or exhaust air from the unit 10 to an outside vent, which may be in the form of wall boxes 42 to permit the stale air to be vented to the outside 40 . It will be appreciated by those skilled in the art that many forms of outside register or vent can be used including a double vent with double grille, a double vent with side exhaust/intake, and two single vents by way of example, all of which are comprehended by the present invention. Most preferably the wall box 42 is provided with at least one flapper valve 43 (see FIGS. 7A and 7B ), to cover the inlet opening when it is not in use. Further, the flapper valve 43 is preferably biased to a closed position, and releasably retained in the closed position such as by a weak magnet or magnetic clasp. In this way, when not in use, the ventilation opening will be closed to prevent bugs, animals and the like from gaining access, and also to preserve energy. The magnetic clasp can be sized and shaped to open for example, under the influence of the air pressure when the fan in the unit is being operated. The present invention further comprehends that flapper valves can be provided over both the air outflow and air inflow openings.
[0041] Similar to a conventional HRV/ERV the present invention allows heat exchange to occur through a heat exchanger core between air exiting the building and air entering the building. In this way the at least some of the energy contained within the air inside the building can be recovered and effectively transferred to the incoming air stream. A number of materials can be used to form the core depending upon the application but good results have been achieved with cores made from aluminum and plastic. For an ERV an enthalpy core is also provided. As with conventional HRVs and ERVs the present invention uses a core consisting of a series of passageways through the core where the fresh and stale air pass past one another separated by a thin heat transfer barrier such as aluminum. This permits the air streams to exchange energy, in a counter current fashion, without permitting direct contact or mixing of the air streams to occur.
[0042] FIG. 2 shows a view of the unit 10 from above. For ease of illustration a cover has been removed to show the internal components. The cover, when in place seals the unit 10 and establishes separation between the inflow air stream and the outflow air stream. The core is shown at 50 within the primary plenum 52 in the unit 10 . A secondary plenum 54 is also shown. Stale air passes through inlet 56 into the core 50 . Once through the core 50 it is passed to an exhaust outlet 58 . Fresh air enters the unit 10 through fresh air inlet 60 , and passes through the core 50 . Fresh air is exhausted from the unit 10 through fresh air outlet 62 . In the preferred embodiment of the present invention two separate variable speed blowers are provided, one at 64 for the fresh air flow through the unit 10 and the other at 66 for the exhaust air flow through the unit 10 . Good results have been achieved with high efficiency, energy saving, permanently lubricated PSC motors which are thermally protected for continuous operation.
[0043] Also shown in FIG. 2 is a defrost damper 70 , controlled by an actuator arm 72 which is in turn attached to a solenoid 74 . Most preferable the defrost damper is automated and comes on in the event the air temperature reaches −5 degrees C. The solenoid 74 is controlled by a controller 76 which is housed in an electrical box 78 . The functions of the controller 76 are described in more detail below. Also shown are hinges 80 , and a backdraft damper 82 .
[0044] FIG. 2 shows the location of airflow diffusers 84 , and 86 which are intended to transform the turbulent airflow produced by the blowers into a more regular or laminar form of air flow. Better results have been achieved with the present invention when the air flow sensors are measuring the air flow across the diffusers than without the diffusers. The diffusers encourage laminar air flow, which can be more reliably measured than can turbulent airflow. According to the present invention air flow sensors 88 ( FIG. 3 ) are positioned in the diffusers 84 , 86 to measure the air flow passing through the unit in both inflow and outflow directions. Although the present invention comprehends having only one airflow sensor 88 the most preferred form of the invention is to include an airflow sensor 88 within each of the fresh air and the stale air streams, so the airflows can be dynamically balanced through electronic fan control.
[0045] The preferred form of airflow sensors 88 are ones which produce an electronic signal that is proportional to or can be correlated to the volume of air flow flowing past the sensor. Although different types of sensors maybe used the preferred sensor is one which is quite sensitive to small temperature changes, and thus can be used to measure air friction, which in turn is an indication of the airflow rate. As will be understood by those skilled in the art, this type of electronic sensor needs to be calibrated to deliver reasonable results. The present invention comprehends other forms of air flow sensors, provided they produce an electronic signal that is proportional to the air flow past the sensor.
[0046] Ideally the cross sectional area of the inflow air stream where it is measured will be the same as the cross sectional area of the outflow air stream where it is measured to ensure that the sensor outputs are directly comparable. The present invention comprehends that the areas could be different, but then the air flows would have to be calibrated and a calibration factor would need to be applied to the sensor readings before they could be directly compared. Therefore, for ease of operation positioning the sensors in air flows of identical cross sectional areas makes the operation of the device easier.
[0047] In the most preferred embodiment of the present invention the electronic signals produced by the two sensors are provided to the controller on a continuous basis. As will be appreciated by those skilled in the art various sample rates can be used to transmit the air flow data to the controller. A preferred range of sample rates is between once per second and once per millisecond, although other rates are also comprehended by the present invention. When the signals are received by the controller the controller makes a comparison to determine if the signals representing the in air flow and the exhaust air flow are the same or different. In the event that a difference is detected the controller sends a motor control signal to each of the blowers to try to reduce the difference. In order to avoid uncontrolled oscillations in motor speeds a dampening algorithm is used. In this way the present invention provides for a motor control system that is continually seeking to reduce the difference between the air inflow rate and the air exhaust rate.
[0048] In the most preferred form of the invention when the air flow rates are sufficiently close then the controller does not send out a motor control signal and does not adjust the speed of the blowers. Although different sensitivities can be used keeping the measured air flow rates within about 5% of each other has been found to provide adequate results.
[0049] FIG. 3 shows a view of a diffuser of FIG. 2 . This shows the diffuser 84 with the air flow sensor mounted to one of the ribs 90 . Air flowing through said diffuser therefore impinges on the electronic air flow sensor whereby an electronic signal can be created which is generally proportional to the volume of air flowing past the sensor. This signal is then sent to the controller. As will be understood by those skilled in the art the air flow sensor is operatively connected to the controller, either directly by wire or by a wireless connection as is known in the art.
[0050] FIG. 4 shows a remote wall unit 98 that can be used to control the operation of the unit. The wall unit includes a display 100 for the purpose of displaying to the user the state of operation of the unit. A variety of settings are possible, including, an adjustable air flow rate with for example four low speeds rates of between about 45 to 95 CFM and four high speed rates of about between 95 to 125 CFM being preset into the controller. These rates are appropriate for a unit to service the fresh air needs of a living space having a floor area of about 2000 square feet. Other flow rates and sizes of units may be appropriate for larger living spaces.
[0051] Preferably the wall unit 98 includes push buttons 102 to permit a user to control the unit 10 . The display 100 can show what mode of operation the unit 10 is in including off, normal, high, recirculating, or energy saving modes. The display also preferably includes a humidity and error display and permits humidity settings of up to 80% relative humidity. Ideally two defrost modes are also provided, one in which the air is recirculating and the other in which the air is not recirculating. There may be multiple controls operatively connected to a single unit 10 and it is preferred that they be wired directly to the unit 10 to eliminate the need for batteries in the wall unit. Another mode of operation can be manual air balancing instead of automatic air balancing, but automatic air balancing will be used most often. The manual air balancing setting can be used to check on the calibration of the system, and the present invention provides for preformed pitot tube insertion openings 200 ( FIG. 6 ) strategically position in the cover plate to permit the balancing of the unit to be manually checked from time to time.
[0052] According to the present invention the unit 10 has power ratings of 115V/1/60 Hz, 1.10 Amp. Also the preferred standby current is about 7 W.
[0053] FIG. 5 shows the bottom panel 110 of the unit 10 (when the unit is installed horizontally). This bottom panel includes a sloped impression 112 that is pressed into the panel, for the purpose of allowing the unit to sit level, even though the core is set at a slight angle relative to horizontal. Many different angles can be used but good results are achieved with an angle of between 1 degree and 10 degrees, most preferably about 2 degrees. All that is required is to provide enough of an angle to the core to ensure that any condensation which condenses on the core is encouraged to drain out of the core and then out of a drain. A drainage tube can be provided to direct the condensation to a house or floor drain in a known manner. It will now be appreciated that the sloped impression 112 provides for an automatically draining core which is simple and easy to fabricate and reliable in terms of establishing good drainage of the core.
[0054] FIG. 6 shows a plan view of a schematic of the present invention. As shown, the dampers 84 , 86 are placed on opposite sides of the main plenum 52 , each damper includes an associated air flow sensor 88 . The blower motors 64 and 66 are shown, to force the air through the core (not shown). A humidity sensor 210 is also shown along with a temperature sensor 214 . As well a safety switch 216 is also provided to cause the unit to shut off in the event the lid is removed. The temperature sensor 214 , and the humidity sensor 210 are used to help control the unit 10 and the readings may also be displayed in the display 100 of the wall unit 98 .
[0055] FIG. 7A shows a side view of an embodiment of a wall box exhaust 42 A and FIG. 7B shows a side view of an embodiment of a wall box intake 42 B. Each of the wall boxes 42 A and 42 B include a magnetic flapper valve 43 A and 43 B, respectively. Each of the wall boxes 42 A and 42 B include a baffle 120 which has a neoprene backdraft damper 122 . Each baffle 120 is biased towards a corresponding magnet 124 . Airflow direction is shown by arrows in each of FIGS. 7A and 7B . As shown in FIG. 7A , airflow travels out of the exhaust wall box 42 A. As shown in FIG. 7B , airflow travels into the intake wall box 42 B. The baffle 120 is biased against the direction of airflow to ensure that the ventilation openings are closed when not in use.
[0056] FIGS. 8A and 8B show an electronic timer switch 126 . The timer switch 126 allows the user to activate the HRV or ERV units on high speed for periods of time, such as 20, 40 or 60 minutes. The timer switch 126 can be activated by the user pressing the button 130 . LEDs 132 are shown on the side of the timer switch 126 . All 3 LEDs 132 will blink to indicate error if any failure is detected on the HRV or ERV.
[0057] The operation of the present invention can now be understood. Once energized, the controller will send a control signal to the fresh air motor to provide a certain preset flow rate, for example, a low flow of 55 CFM. This will cause the fresh air blower to start to draw fresh air through the heat exchange core. At the same time, a motor control signal will be sent to the exhaust air flow blower, to cause it to operate at almost the same speed. However, although approximately equal control signals can be sent, there is no guarantee that the actual air flows will be the same due to variations in aerodynamic head and the like. At this point any magnetized dampers on the outside vent or boxes will have been opened by the air pressure caused by the blowers.
[0058] The next step is for the air flow sensors to begin sampling the air flow flowing past them through the dampers. At this stage the sensors are going to produce an electronic signal which is generally proportional to the air flow past each sensor. As noted above generally laminar air flow provides more reliable air flow measurements and laminar air flow can be encouraged by using diffusers as shown. Further by ensuring that the cross sectional area of the two air flows is about the same, the sensor readings can be reliably compared.
[0059] The next step is to communicate the electronic signal which is proportionate to the air flow, so the two signals, from inbound fresh air and outbound stale air can be compared. The comparison can be made in any convenient way including simply summing the electrical values of the signals, or translating the signals into some form of value and then comparing the values. Once the comparison is made, an adjustment is made to one or both of the motor speeds to reduce any difference detected. A statistical sampling algorithm can be used to smooth out the readings, such as taking an average reading from a number of readings taken over a predetermined time frame. Further the algorithm can take into account that the values are to approach the desired value such as by changing the speed by less the amount required so as to allow the fans to approach the same speed without constant overshooting.
[0060] Also, the present invention comprehends that a threshold value can be used to decide that the air flows are close enough that no further adjustment is required. Most preferably there would be no adjustment required of the air flows are within eight percent or lower at each other and ideally being within about five percent is desired. Now the system of the present invention is going to continuously dynamically balance the air flows even as certain environmental factors, such as air pressure, changes. In this way the present invention provides a reliable balanced air flow for the unit as a whole. Even if the air flow rate is changed, for example is increased to 95 CFM the sensors will again measure the difference between inflow and outflow air speeds and engage in continuous dynamic balancing by means of individual blower motor control, but simply with the different higher air air flow rate used as the target rate for the set point. As will be understood by those skilled in art the preferred form of the invention uses identically sized inflow and outflow cross-sectional areas where sensors are located. Identical areas allow the signals to be directly compared. The present invention comprehends using different sized areas, but in that case a flow area calibration factor would need to be used before comparing the signals.
[0061] While the foregoing description includes detailed aspects of one or more preferred embodiments it will be understood by those skilled in the art that many modifications and variations of the invention are possible without departing from the scope of the appended claims. Some of these have been discussed above and others will be apparent to those skilled in the art. For example, while the preferred position for the blowers is as shown in the drawings, the blowers could be placed on the opposite side of the unit and still function in generally the same manner. | A heat and energy recovery ventilation unit for a building, having an inside and an outside. The unit including a main body having a fresh air inlet and an indoor air outlet on one side and a fresh air outlet and an indoor air inlet on the other side and having an air to air heat exchanger within the main body and connected to each of said inlets and outlets to define respective air flow passageways for each of said indoor air and said fresh air, the heat exchanger permitting heat and energy exchange between said indoor air and said fresh air. Also included is a first variable speed blower and a second variable speed blower and at least one electronic air flow sensor to measure at least one of the air flows the air flow sensor producing at least one electronic signal related to the sensed air flow. Also included is a controller for receiving the data signal, the controller using the data signal to control at least one of the variable speed blowers to provide a balanced fresh air inflow and indoor air outflow through the ventilation unit. A method of operating the unit is also disclosed. | 5 |
RELATED APPLICATIONS
[0001] This application claims priority of U.S. Provisional Ser. No. 60/859,387 filed Nov. 15, 2006, the content of which are incorporated herein by reference.
FIELD OF THE INVENTION
[0002] The present invention relates to the removal of substances from substrate surfaces and, more particularly, to compositions that, when applied to certain substances, alter the characteristics of the substances to facilitate removal of the substances from a variety of substrate surfaces.
BACKGROUND OF THE INVENTION
[0003] The process of removing a substance that has been intentionally or unintentionally applied to a substrate surface is significantly simplified if the characteristics of the applied substance are altered. For example, removal of chewing gum from a carpet or fabric is simplified if the gum is softened or otherwise dissolved. Similarly, permanent ink can be wiped off of a painted surface more easily when dissolved into liquid form.
[0004] A number of remover compositions have been formulated to alter the characteristics of a variety of applied substances to facilitate removal of these applied substances from a variety of substrate surfaces. Ideally, such remover compositions typically comprise solvents that are formulated to break down the applied substance without permanently damaging the material defining the substrate surface.
[0005] Recently, however, various government entities have enacted regulations that effectively restrict the use of certain solvents in conventional remover compositions. This includes, but is not limited to, the weight percentage of Volatile Organic Compounds (VOC) used and several chlorinated solvents.
[0006] The need thus exists to develop new remover compositions that effectively alter the characteristics of a variety of applied substances to facilitate removal of these applied substances from a variety of substrate surfaces but which also meet governmental regulations.
SUMMARY OF THE INVENTION
[0007] The present invention may be embodied as a remover composition comprising a primary solvent and at least one of a secondary solvent portion and an additive portion. The primary solvent portion has a K b value of substantially between 25 and 40. The percentage by weight of primary solvent portion is within a primary solvent range of less than approximately 99% of the remover composition.
DETAILED DESCRIPTION
[0008] The present invention may be embodied as a remover composition comprising materials that, when combined, provide a balance of characteristics that is desirable in a composition for removing a variety of applied substances from a variety of substrates.
[0009] A remover composition of the present invention comprises a primary solvent portion and a secondary solvent portion comprising at least one secondary solvent. Many typical applied substances are formed at least in part of organic materials, and the purpose of the primary and secondary solvent portions is to dissolve or otherwise loosen these organic materials.
[0010] A remover composition of the present invention may further comprise one or more additional components such as a fragrance portion comprising at least one fragrance, a colorant portion comprising at least one colorant, a gellant portion comprising at least one gellant material, and a surfactant. The fragrance portion may provide the remover composition with an aesthetically pleasing odor or, depending upon the solvents used, may cover up displeasing odors. The colorant portion provides a color to the remover composition. The gellant portion is a thixotropic agent that causes the remover composition to form a gel when applied to the substrate. The surfactant conventionally facilitates spreading of the remover composition.
[0011] The primary solvent portion, secondary solvent portion, and additional components that may be used to create a remover composition according to the principles of the present invention will each be discussed in further detail below.
I. PRIMARY SOLVENT PORTION
[0012] The primary solvent portion is formed of a low vapor pressure volatile organic compound (LVP-VOC) having a Kauri-Butanol Value (K b value) of substantially between 15 and 40. The California Air Regulatory Board (C.A.R.B.) uses the term “LVP-VOC” to define a particular class of chemical compounds or mixtures that contain at least one carbon atom and, among other possible physical attributes, vaporize very slowly at 20 degrees Celsius. The term “K b value” refers to a number indicative of the solvency of a material and is measured using an industry standard test procedure.
[0013] The following Table A contains a list of materials that may be used, alone or in combination, as the primary solvent portion:
[0000]
TABLE A
Scientific Name
CAS number
Example Ingredient (Supplier)
Hydrotreated Light
64742-47-8
LVP 200 (Calumet Lubricants
Distillates (petroleum)
Co.)
Hydrotreated Light
64742-47-8
LVP 100 (Calumet Lubricants
Distillates (petroleum)
Co.)
Conosol C-200 (Penreco)
Isopar M (Exxon Mobile
Corporation)
Isopar V (Exxon Mobile
Corporation)
64771-72-8
Norpar 15 (Exxon Mobile
Corporation)
Isoparaffinic
Hydrocarbons
Cycloparaffinic
Hydrocarbons
II. SECONDARY SOLVENT PORTION
[0014] The secondary solvent portion is formed of a solvent having a Kauri-Butanol Value (Kb value) of greater than 40. The following Table B contains a list of materials that may be used, alone or in combination, as the secondary solvent portion:
[0000]
TABLE B
Scientific Name
CAS number
Example Ingredient (Supplier)
1-Methyl-4-(1-
94266-47-4
d-Limonene
methylethenyl)
cyclohexene
Citrus Terpenes
Orange Extractives
Citrus Extractives
8028-48-6
Cold Pressed Orange Oil
Tripropylene Glycol
25498-49-1
(Mono) Methyl Ether
(TPM)
Propylene based
PM, DPM, PE, PNP, DPNP,
glycol ethers
PNB, DPNB, TPNB, PTB
Ethylene based
DM, DE, EB, DB
glycol ethers
Tertiary Butyl Acetate
540-88-5
TBAc
III. ADDITIONAL COMPONENTS
[0015] If used, the colorant portion can be any compatible dye or pigment material that results in the remover composition having a desirable color. One example material that may be used as the colorant portion is identified by the scientific names Perinone or Monoazo (CAS Number 6925-69-5) and ingredient name Pylakrome Orange Dye LX-10710.
[0016] If used, the fragrance portion can be any compatible fragrance material that results in the remover composition having a desirable fragrance. One or more of the following materials may be used as the fragrance portion: Amyl Acetate (Primary, mixed isomers), Pentyl Acetate (CAS Number 628-63-7), 2-Methyl Butyl Acetate (CAS Number 624-41-9), and Isoamyl Acetate (CAS Number 123-92-2).
[0017] It should be noted that certain of the secondary solvent materials listed above have aromatic properties that may eliminate the need for a separate fragrance material. Alternatively, it may be desirable to blend the fragrance of a separate fragrance material with the fragrance of the secondary solvent materials to obtain a unique, desirable, and/or recognizable blended fragrance.
[0018] If used, the gellant portion can be any compatible gel material that results in the remover composition having desirable body and thickness when applied to the substrate surface. The gel portion can provided to the remover composition one or more of the following desirable characteristics: inhibit dripping or running of the remover composition; inhibit drying of the remover composition before the solvent portions can adequately penetrate the applied substance; and/or improve the consistency of the remover composition during application. An example of a gel material suitable for use as the gel portion is Sylvagel 6100 (Arizona Chemical).
[0019] If used, the surfactant may be any compatible surfactant material that lowers the surface tension of the remover composition. By lowering the surface tension of the remover composition, the surfactant facilitates spreading of the remover composition. An example of a suitable surfactant is Tomodol.
IV. EXAMPLE REMOVER COMPOSITIONS
[0020] The following examples list several formulations of remover compositions by percent weight of the ingredient materials:
Example 1
[0021]
[0000]
First
Second
Component (Ingredient)
Range
Range
Example
Primary Solvent Portion
>68.0
80.0-94.0
87.1
(LVP 200)
Secondary Solvent Portion I
0-30.0
5.0-14.0
9.5
(d-Limonene)
Secondary Solvent Portion II
0-20.0
1.0-5.0
3.0
(TPM)
Fragrance Portion (Amyl
0-5.0
0.1-0.7
0.4
Acetate)
Example 2
[0022]
[0000]
First
Second
Component (Ingredient)
Range
Range
Example
Primary Solvent Portion (LVP
>68.0
86.0-99.0
97.0075
200)
Secondary Solvent Portion
0-30.0
0.9-9.0
2.99
(Cold Pressed Orange Oil)
Colorant Portion (Pylakrome
0-2
0.00001-0.1
0.0025
Orange)
Example 3
[0023]
[0000]
First
Second
Component (Ingredient)
Range
Range
Example
Primary Solvent Portion (LVP
>68.0
80.0-94.0
87.4975
200)
Secondary Solvent Portion I
0-30.0
3.0-10.0
6.5
(d-Limonene)
Secondary Solvent Portion II
0-20.0
1.0-5.0
3.0
(Cold Pressed Orange Oil)
Secondary Solvent Portion III
0-5.0
1.0-3.0
3.0
(TPM)
Colorant (Pylakrome Orange
0-1.0
0.0010-0.0040
.0025
(LX10710 Pylam))
Example 4
[0024]
[0000]
First
Second
Component (Ingredient)
Range
Range
Example
Primary Solvent Portion (LVP
>75.0
89.0-99.0
94.9975
200)
Secondary Solvent Portion I
0-23.0
1.0-11.0
3.0
(TPM)
Secondary Solvent Portion II
0-23.0
1.0-11.0
2.0
(Citrus Boost)
Colorant Portion (LX10710
0-1.0
0.0010-0.0040
.0025
Pylam)
Example 5
[0025]
[0000]
First
Second
Component (Ingredient)
Range
Range
Example
Primary Solvent
>60.0
85.0-99.0
92.89825
Portion (LVP 200)
Secondary Solvent
0-20.0
1.0-9.0
3.0
Portion I (TPM)
Secondary Solvent
0-20.0
1.0-6.0
2.0
Portion II
(Citrus Boost)
Gellant Portion
0.1-10.0
1.0-6.0
2.1
(Sylvagel 6100)
Colorant (Pylakrome
0-1.0
0.00010-0.00500
0.00150
Orange (LX10710
Pylam))
Colorant (Pylakrome
0-1.0
0.00010-0.00050
0.00025
Scarlet (LX-10048
Pylam))
Example 6
[0026]
[0000]
First
Second
Component (Ingredient)
Range
Range
Example
Primary Solvent
>60.0
74.0-88.0
81.14825
Portion (LVP 200)
Secondary Solvent
0-30.0
6.0-20.0
12.5
Portion (d-Limonene)
Surfactant (Tomodol)
0-10.0
2.0-12.0
4.0
Gellant Portion
0.1-10.0
1.0-6.0
1.8
(Sylvagel 6100)
Fragrance/Solvent
0-30.0
0.10-1.5
0.5
(Concentrated
Orange Oil)
Fragrance (Ethyl
0-5.0
0.01-0.10
0.05
Butyrate)
Colorant (Pylakrome
0-1.0
0.00010-0.00500
0.00150
Orange (LX10710
Pylam))
Colorant (Pylakrome
0-1.0
0.00010-0.00050
0.00025
Scarlet (LX-10048
Pylam))
[0027] The scope of the present invention should be determined with respect to any claims appended hereto and not the foregoing detailed description. | A remover composition comprises a primary solvent and at least one of a secondary solvent portion and an additive portion. The primary solvent portion has a K b value of substantially between 25 and 40. The percentage by weight of primary solvent portion is within a primary solvent range of less than approximately 99% of the remover composition. | 2 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority to U.S. Provisional Patent Application No. 60/481,390 filed on Sep. 17, 2003, the contents of which are incorporated herein by reference.
BACKGROUND OF INVENTION
[0002] The present invention relates to a method and apparatus for detection of tumors, and particularly tumors in human breast tissue.
[0003] The purpose of any imaging system for breast cancer detection is to assist in the diagnosis of early stage breast cancer. Currently, women are encouraged to participate in breast cancer screening programs utilizing mammography. Mammograms are x-rays images of a compressed breast, and are acknowledged to be the leading method of breast imaging currently available. While mammography is very sensitive to lesions in the breast, it has acknowledged limitations. For example, mammograms create images of the breast based on density differences and there may be only a slight difference in density between normal tissue and tumors. This is especially problematic for imaging women with dense breasts, which comprise a significant portion of the population. Another limitation is that a lesion may not be immediately diagnosed via a single mammogram. Further investigation of suspicious areas involves additional mammography, ultrasound and, in some cases, biopsy. Less than 10% of the suspicious areas investigated are diagnosed as cancer.
[0004] Every time a mammogram is taken, the patient incurs a small risk of having a breast tumor induced by the ionizing radiation properties of the X-rays used during the mammogram. Also, the process is sometimes imprecise and, as a result, not cost-efficient. Accordingly, the National Cancer Institute has not recommended mammograms for women under fifty years of age, who are not as likely to develop breast cancers as are older women. However, while only about twenty two percent of breast cancers occur in women under fifty, data suggest that breast cancer is more aggressive in pre-menopausal women.
[0005] Mammograms require interpretation by radiologists who can spot cancers between five and ten millimeters in diameter, and the prognosis is excellent in those cases. However, about ten to fifteen percent of tumors of this size and most tumors below this size are not detected. One study showed major clinical disagreements for about one-third of the same mammograms that were interpreted by a group of radiologists. Further, many women find that undergoing a mammogram is a decidedly painful experience.
[0006] These limitations have generated interest in alternative breast imaging methods. Many medical imaging technologies have been applied to this problem, including ultrasound and magnetic resonance (“MR”) imaging. Ultrasound is often used to differentiate solid tumors from liquid cysts, but does not provide definitive information on whether a solid tumor is malignant or benign. MR imaging provides a map of the tissue distributions in the breast, and MR breast imaging usually involves injection of a contrast agent. The uptake and washout of the contrast agent in the vicinity of the suspicious lesion is monitored, however it may be difficult to provide a definitive diagnosis as malignancies generally do not have behavior that is consistently and distinctly different than benign lesions.
[0007] Therefore, there is a need in the art of medical imaging for a complementary breast imaging tool. Specifically, imaging tools that may be applied to women with suspicious mammograms to quickly and effectively indicate the presence or absence of a tumor would be of great value. The keys to a successful technology are the presence of a consistent contrast between normal breast tissues and malignant lesions, and a difference in the response of benign and malignant tissues. In other words, a physical basis for tumor detection must exist.
[0008] Microwave imaging for breast tumor detection is considered to be promising, as it is believed that there is a significant or detectable contrast in malignant, benign and normal tissues over a broad frequency range.
SUMMARY OF INVENTION
[0009] Several approaches to microwave breast imaging have been proposed, including tomography and radar-based methods. Tomography reconstructs a map of the electrical properties in the breast using measurements of energy transmitted through the breast. Radar-based approaches detect strongly scattering objects (tumors) using measurements of energy reflected from the breast. The present invention utilizes a radar-based approach.
[0010] Radar-based imaging methods may also be known as confocal microwave imaging (CMI). Reflections may be observed at a number of antennas located on the breast, and images may be created by summing the reflections or synthetically focusing these reflections. Synthetic focusing involves calculating the time-delay from each antenna to a focal point, and time-shifting and summing the recorded signals. If a tumor was located at the focal point, then reflections from the tumor add together, resulting in a large contribution to the image at that focal point location. With the focal point in normal tissues, reflections tended to add incoherently, resulting in a small contribution to the image. By scanning the focal point through the volume of interest and observing areas of strong reflection, tumor detection and localization is possible.
[0011] In one aspect, the invention may comprise a method of detecting the presence or absence of a tumor within a breast including skin and an interior volume, comprising the steps of:(a)illuminating the breast with microwaves from a plurality of locations and recording the reflections received at each location as a signal;(b)identifying a first skin reflection and a second skin reflection separated by a period of time and time-gating the signal by setting all data arriving before the first skin reflection and after the second skin reflection to zero;(c)creating a first estimate of reflections from the skin and subtracting said first skin reflections from each signal;(d)creating a second estimate of reflections from the skin for a single location from the signals received in at least two adjacent locations and subtracting the second skin reflections from each signal; and(e)constructing a three-dimensional image of the interior volume from the signals showing the presence or absence of microwave reflecting tissues.
BRIEF DESCRIPTION OF DRAWINGS
[0012] The invention will now be described by way of an exemplary embodiment with reference to the accompanying simplified, diagrammatic, not-to-scale drawings. In the drawings:
[0013] FIG. 1 is a schematic representation of a modified patient bed used in an imaging scan of the present invention.
[0014] FIG. 2A is a schematic representation of the two-dimensional initial scan locations used to image or localize the skin. FIG. 2B is a schematic representation of the antenna locations used in a tumor detecting scan after the initial scan has taken place.
[0015] FIG. 3 is a representation of the image of skin resulting from a simulated two-dimensional skin sensing initial scan.
DETAILED DESCRIPTION
[0016] The present invention provides for a method and apparatus for tissue sensing adaptive radar imaging of breast tissue. When describing the present invention, all terms not defined herein have their common art-recognized meanings. As used herein, “microwave” means non-ionizing electromagnetic radiation which has a wavelength between about 10− 4 to 10− 1 m, and frequencies in the range of about 10 8 to about 10 10 Hz. The term “radar” refers to a method of detecting the presence and location of an object by detecting reflections of microwave radiation from the object. Microwave imaging in medical situations is well described in a publication entitled “Medical Applications of Microwave Imaging”, edited by L. E. Larsen and J. H. Jacobi, IEEE Press 1986, the contents of which are incorporated herein by reference. The term “tissue sensing” means a process of radar imaging which may distinguish between various tissues of the breast such as skin, glandular tissue, and tumors. The term “adaptive” means a process of radar imaging which incorporates signal manipulation steps to remove non-tumor reflective signals using localized or signal-specific information.
[0017] The system of the present invention may be described as a tissue-sensing adaptive radar system. The physical basis for breast tumor detection with microwave imaging is the contrast in dielectric properties of normal and malignant breast tissues. In general terms, the system includes a plurality of wideband antennas for illuminating the breast and collecting the reflections as well as a computer system for acquiring the data and synthesizing an image from the accumulated data. The system is able to isolate reflections coming from a specific location within a three-dimensional volume, which in the present instance, is defined by the volume of the breast. The following description is of a preferred embodiment of the invention, which is not intended to be limiting of the claimed invention.
[0018] The preferred method of radar scanning in the present invention is referred to herein as “cylindrical” scanning. In a cylindrical scan, the patient lies face down on a modified patient bed which has a well for the breast to fall into. The well may include a gel or a liquid to better conform the breast to the surface of the well and the antennas. The antennas may be integrated into the surface of the well or may be moved around the well as shown in FIG. 1 . In one embodiment, the antennas may be conformal antennas integrated by printing onto the surface of the well.
[0019] The antennas preferably comprise wideband antennas such as standard TEM horn antennas which are well known in the art. They may be adapted to effectively operate in a dielectric similar to either skin or fat tissue.
[0020] The present invention proceeds with data acquisition in two steps. First, an initial scan is performed to locate the breast in the imaging volume, and second, a tumor-sensing scan is performed to locate reflecting structures (such as a tumor) within the breast. The scans may be performed with a single antenna which is moved from location to location or a plurality of antennas in an array. It is not necessary that the initial scan be performed with microwaves as it is a boundary sensing step. It is possible to perform the initial scan with an alternative method such as using higher frequency signals which have shallower penetration or laser light.
[0021] The initial scan may be performed along one two-dimensional path or a set of two-dimensional paths as shown in FIG. 2A . The antenna may be moved (or multiple antennas provided) to a plurality of locations along the z direction, then a plurality of locations in the x direction, and finally a plurality of locations again in the z direction. With antennas integrated into the scanning bed, a subset of the antennas may be used for this scan.
[0022] The tumor-sensing scan is preferably done to form a synthetic conical array. The antenna may be moved to a plurality of locations along a row (x-y plane), with multiple rows spanning from the nipple to the chest wall, as shown in FIG. 2B .
[0023] As most microwave measurement equipment is intended for use in the frequency domain, the measured data are in the frequency domain. In order to obtain reasonable resolution for the images and maintain compatibility with the image formation algorithms described herein, conversion to time domain signals is required. A weighting window is applied to the measured data to produce the desired time-domain pulse.
[0024] This pulse may be a differentiated Gaussian pulse with maximum frequency content near 5.24 GHz and full-width half-maximum (FWHM) bandwidth from 1.68 to 10 GHz. Any pulse with ultra-wideband frequency content in the range of 0.1 to 10 GHz may be suitable for use. The weighted signals are transformed to the time domain either with inverse Fourier transforms or, more preferably, inverse chirp-z transforms, both of which are well known in the art. The latter provide flexibility in selection of the time step and smaller time steps may assist in clutter reduction.
[0025] The recorded signals have early and late time content. The early time content is dominated by the incident pulse, reflections from the skin and residual antenna reverberations. The late time content contains tumor backscatter and backscatter due to clutter. The signal processing goals are to reduce the early-time content, which is of a much greater amplitude than the tumor response, and to selectively enhance the tumor response while suppressing the clutter to permit reliable detection of tumors in the reconstructed images. The images are reconstructed using the image formation steps described below.
[0026] First, the signals are calibrated by removing the response of the antenna, which is done by subtracting the signal received at the antenna without any scattering object present. Next, an image is formed by synthetically scanning the focal point through the region inside the array. The resulting image indicates the location of the skin, and the imaging region for detection is defined using this information. The results of a simulated two-dimensional skin sensing scan is shown in FIG. 3 . Thresholding or filtering of the image is used to identify the skin, edges are identified by the largest group of connected pixels and all other pixels are removed from the resulting image of the skin. The pixels located closest to and farthest away from each antenna are assumed to represent the first and second skin interfaces. The initial image of the skin formed from the initial skin-sensing scan is then used to determine an appropriate time-gate for the sensing scan data. In order to limit data to reflections from within the volume defined by the skin, the calibrated data arriving before the first skin reflection and after the second skin reflection are set to zero.
[0027] A two-step process may be used to reduce the reflection from the skin. These steps are applied to the signal recorded at each antenna or each location. The first step estimates the skin reflection using signals recorded at a number of antennas near the current antenna. The signal recorded at the current antenna is referred to as the target signal. The signals at neighboring antennas are matched to the target signal by time-shifting and scaling each signal in turn. This process is repeated several times in order to obtain the best match. The estimate of the target is obtained by taking the average of the shifted and scaled set of signals. A separate estimate is calculated for each antenna. The estimates are likely to be different, as each target signal requires different time-shifts and scaling. The estimate for each antenna is subtracted from the target signal. The resulting signal is likely to contain imperfectly cancelled reflections. This first step estimates the large reflection from the interface between the immersion liquid and the skin. A second reflection is generated from the interface between the skin and the interior of the breast. These reflections are likely similar at neighboring antennas, as the underlying tissues are expected to be somewhat similar.
[0028] The second step in the skin subtraction process provides an estimate of the reflections remaining in the signal after the first subtraction, which are related to local tissue variations. The estimate in this step is formed with the subtracted signals at the neighboring antennas. Again, the signals are scaled and time-shifted to match the target signal and the estimate is the average of the set of signals. This estimate is subtracted from the target signal. This two-step process may be referred to as “adaptive estimation” of the skin reflection.
[0029] The technique of adaptive estimation may also be used to estimate and subtract reflections from other strongly scattering objects, such as blood vessels and glandular tissue.
[0030] The calibrated signals, with greatly reduced skin and other non-tumor reflections, may then be adjusted such that the value of the signal at its midpoint in time corresponds to the maximum amplitude of the signal. For example, a differentiated Gaussian excitation signal has a zero-crossing at its centre point in time. The backscattered signal that would follow after a specific time delay corresponding to the round-trip distance between the antennas and the scattering object (tumor) would also have a zero-crossing at its centre point.
[0031] The processed signals are synthetically focused at a plurality of specific points in the breast. First, distances from each antenna to each focal point are computed and converted into time delays. Focusing includes a weighting based on relative distance between the focal point and antennas. In a preferred embodiment, path loss compensation is not required. The time delays are used to identify the contribution from each processed signal. All contributions are summed and the squared value of this sum is assigned to the pixel value at the focal point. An estimate of the velocity of propagation of the signal in the medium is used. The focal point is scanned to a new location in the region of interest, and this process is repeated. The focal point coordinates are defined with respect to the defined volume within the skin. Focusing may include a weighting based on relative distance between the focal point and antennas. This gives greater emphasis to data recorded at antennas located near the focal point. It may also be preferable to filter the image to emphasize pixels nearer the center of the scanned volume.
[0032] In one embodiment, the microwave imaging of the present invention may be combined with other imaging methods such as magnetic resonance (MR) techniques. MR images provide excellent definition of various tissue types, and blood vessels larger than about 1 mm may be imaged with time-of-flight angiography, as is well known in the art. The comparison or co-registration of MR and microwave images provides complementary information for image interpretation. For example, clutter in a microwave radar image may be identified as arising from tissue structures in the breast, or a lesion that enhances in a MR scan may be shown to be a strongly scattering object in a microwave image.
[0033] As will be apparent to those skilled in the art, various modifications, adaptations and variations of the foregoing specific disclosure can be made without departing from the scope of the invention claimed herein. The various features and elements of the described invention may be combined in a manner different from the combinations described or claimed herein, without departing from the scope of the invention.
[0034] References
[0035] The following references are incorporated herein as if reproduced in their entirety.
References
[0000]
[1] P. M. Meaney, K. D. Paulsen and M. W. Fanning, “Microwave imaging for breast cancer detection: preliminary experience,” Proceedings of SPIE , vol. 3977, 2000, pp. 308-319.
[2] S. C. Hagness, A. Taflove, and J. E. Bridges, “Two dimensional FDTD analysis of a pulsed microwave confical system for breast cancer detection: Fixed-focus and antenna-array sensors,” IEEE Trans. Biomed. Eng ., vol. 45, pp. 1470-1479, Dec. 1998.
[3] S. C. Hagness, A. Taflove, and J. B. Bridges, “Three-dimensional FDTD analysis of a pulsed microwave confocal system for breast cancer detection: Design of an antenna-array element,” IEEE Trans. Antennas Propag ., vol. 47, pp. 783-791, May 1999.
[4] E. C. Fear, X. Li, S. C. Hagness and M. A. Stuchly, “Confocal microwave imaging for breast tumour detection: localization of tumours in three dimensions,” IEEE Trans. Biomed. Eng ., vol. 49, pp. 812-822, Aug. 2002.
[5] X. Li and S. C. Hagness, “A confocal microwave imaging algorithm for breast cancer detection,” IEEE Microwave Wireless Comp. Lett ., vol. 11, pp. 130-132, March 2001.
[6] E. C. Fear, J. Sill and M. A. Stuchly, “Experimental feasibility study of confocal microwave imaging”, IEEE Trans. Microw. Theory Tech ., accepted, Sept 2002.
[7] E. J. Bond, E. J. Bond, X. Li. S. C. Hagness, and B. D. Van Veen, “Microwave imaging via space-time beamforming for early detection of breast cancer”, 2002 IEEE International Conference on Acoustics, Speech, and Signal Processing , vol. 3, 2002, pp. 2909-2912.
[8] D. K. Ghodgaonkar, V. V. Varadan, and V. K. Varadan, “A free-space method of measurements of dielectric constants and loss tangents at microwave freqencies”, IEEE Trans. Instru. Meas ., vol. 37, pp. 789-793, June 1989.
[9] R. Olmi, M. Bini, A. Ignesti and C. Riminesi, “Non-destructive permittivity measurement of solid materials”, Meas. Sci. Technol ., vol. 11, pp. 1623-1629, 2000.
[10] J. Baker-Jarvis, M. D. Janezic, J. H. Grosvenor Jr., R. G. Geyer, “Transmission-reflection and short-circuit line methods for measuring permittivity and permeability”, NIST Technical Note 1355 (revised), Dec. 1993.
[11] B. Ulriksson, “Conversion of frequency-domain data to the time domain,” Proc. IEEE , vol. 74, pp. 74-77, Jan. 1986
[12] D. A. Frickey, “Using the inverse chirp-z transform for time-domain analysis of simulated radar signals,” Proceedings of the 5 th International Conference on Signal Processing Applications and Technology , Dallas, TX, USA, Oct. 18-21, pp.1366-1371, 1994.
[13] A. Taflove and S. C. Hagness, Computational Electrodynamics: The Finite-Difference Time-Domain Method, 2 nd ed ., Artech House: Boston, 2000.
[14] C. D. Woody, “Characterisation of an adaptive filter for the analysis of variable latency neuroelectric signals ”, Medical Biological Eng ., vol. 5, pp. 539-553, Feb. 1967. | A tissue-sensing adaptive radar method of detecting tumours in breast tissue uses microwave backscattering to detect tumours which have different electrical properties than healthy breast tissue. The method includes steps for reducing skin reflections and for constructing a three-dimensional image using synthetic focusing which shows the presence or absence of microwave reflecting tissues. | 0 |
This application is a continuation-in-part of application Ser. No. 785,303, filed Apr. 6, 1977, now abandoned.
BACKGROUND OF THE INVENTION
Structural arrangements for the open-circuit liquid cooling of gas turbine buckets are shown by Kydd, U.S. Pat. Nos. 3,445,481 and 3,446,482. The first patent discloses a bucket having cooling passages open at both ends which are defined by a series of ribs forming part of the core portion of the bucket and a sheet metal skin covering the core and welded to the ribs. The second patent discloses squirting liquid under pressure into hollow forged or cast turbine buckets. Another patent issued to Kydd, U.S. Pat. No. 3,619,076 described an open circuit cooling system wherein a turbine blade construction consists of a central airfoil-shaped spar which is clad with a sheet of metal having a very high thermal conductivity, e.g. copper. The cladding sheet has grooves recessed in the sheet face adjacent to the spar, which grooves together with the smooth surface of the spar define coolant passages distributed over the surface of the turbine blade. There are numerous disadvantages in forming liquid cooling passages by bonding a sheet to a core in either of the configurations shown in U.S. Pat. Nos. 3,445,481 or 3,619,076. Thus, when a braze is used to bond the skin, some channels of the turbine buckets become plugged and obstructed with braze material. Excellent bonds are required between the core and the skin to contain the water in full channel flow under the extremely high hydraulic pressures which result from the centrifugal forces during operation of the turbine. In addition, any cracks in the skin can cause leakage of the coolant and result in vane failure.
Many of the disadvantages of the prior art are overcome by the invention disclosed in the copending application of Anderson, "Liquid Cooled Gas Turbine Buckets," Ser. No. 749,719, filed Dec. 13, 1976, now U.S. Pat. No. 4,156,582. Anderson discloses water cooled turbine buckets wherein the water-cooling channels are formed using preformed tubes which are located beneath an outer protective layer composed of an inner skin to provide high thermal conductivity and an outer skin to provide protection from hot corrosion.
Schilling, et. al., U.S. Pat. No. 3,928,901 and Schilling, et. al., U.S. Pat. No. 3,952,939 both disclose methods of attaching sheet cladding to a convex-concave substrate such as an airfoil or a turbine bucket using isostatic pressing techniques. However, the procedures set forth in these Schilling patents when applied to the manufacture of turbine buckets incorporating preformed tubes will tend to collapse the tubes. Furthermore, when molten glass is used as the pressure transmitting medium as disclosed in U.S. Pat. No. 3,952,939, the molten glass is able to enter the tubes and is then difficult or almost impossible to remove without damage to the tubes.
SUMMARY OF THE INVENTION
In accordance with our invention, we have discovered a method of making composite components, such as turbine buckets and nozzles, for water-cooled, high temperature gas turbines by preparing a cast article having a plurality of channels therein for vacuum brazing. Thereafter a plurality of preformed metal tubing sections are placed into the channels at a preselected portion of said article in such a manner that both ends of each tubing section extends external to said portion. Subsequently, a sheet cladding is preformed to the shape of the portion and the seams formed between the cladding and the portion are masked. Thereafter, the assembly is placed in a molten glass environment, while maintaining said tubing sections extending above the molten glass and the assembly is subjected to a programmed time-temperature hot isostatic pressure cycle during the diffusion bonding step. Alternatively, only one end of each tubing section extends external to the portion and above the molten glass level, while the other end is sealed off.
BRIEF DESCRIPTION OF THE DRAWING
The invention is more clearly understood from the following description taken in conjunction with the accompanying drawing in which:
FIG. 1 is a perspective view, with portions broken away, of a turbine bucket having preformed cooling tubes diffusion bonded to an airfoil according to the method of the present invention.
FIG. 2 is an enlarged fragmental transverse view of the airfoil of FIG. 1 showing the location of a cooling tube.
FIG. 3 is a cross sectional, schematic representation of a turbine bucket in an apparatus for hot isostatic pressing illustrating the principles of the present invention.
FIG. 4 is another cross section, schematic representation of a variation of the embodiment of FIG. 3.
FIG. 5 is yet another cross sectional, schematic representation of a variation of the embodiment of FIG. 3.
FIG. 6 is a graph showing typical pressure-temperature-time curves for the diffusion bonding step.
FIG. 7 is a perspective view, with portions broken away, of a turbine nozzle having performed tubing diffusion bonded to a core according to the method of the present invention.
FIG. 8 is a cross sectional, schematic representation of a turbine nozzle in an apparatus for hot isostatic pressing similar to that shown in FIG. 3.
DESCRIPTION OF PREFERRED EMBODIMENT
Referring to FIG. 1, turbine bucket 10 consists of a shank 12 and a water cooled airfoil 14 constructed from a core 16, having a multiplicity of radial grooves 18 either cast or machined into the surface thereof. The number of these grooves 18 depends on the size and the cooling requirements of the bucket 10. Into these grooves 18 are fitted preformed cooling tubes 20 which are bonded to the core 16 such as by brazing and preferrably have a portion exposed to and in contact with a composite skin 22 which covers and envelopes the outer surface of the core 16. This composite skin 22 is composed of an inner layer or skin 23 which is highly heat conducting to maintain substantially uniform temperature over the surface of the bucket during operation of the turbine, resulting from exposure with the hot gases on the outside of the bucket and the internal water cooling. The preferred inner skin material is copper or a copper containing material which, however, is not resistant to the corrosive atmosphere of the hot gases present during operation of the gas turbine. Therefore, an outer corrosion resistant skin 24 is required to cover and protect the inner skin 23.
The cooling tubes 20 are shown to communicate root plenums 26 and 26A with a plenum 30 formed in a tip shroud 28. Some of the cooling tubes 20 serpentine back and forth on the radially inner side of the tip shroud 28 before emptying into the tip shroud plenum 30. This cools the shroud and aids in the manufacturing process since the shroud cooling channel is a continuation of the airfoil cooling tubes 20. The core 16 is cast along with the tip shroud 28 and the shank 12 and carries the centrifugal load of the tubes 20, the composite skin 22 and the tip shroud 28.
FIG. 2 shows an enlarged, cross-sectional view of the structure of the airfoil 14 in the proximity of the cooling tube 20. As is shown, the cooling tube 20 is fitted into and bonded to groove 18 within the core 16 of the airfoil 14 by means of braze 32. The composite skin 22, which consists of an inner skin 23 and an outer skin 24, overlays the tube 20 and the core 16.
The method of our invention utilizes hot isostatic pressure in combination with molten glass as a pressure transmitting medium to fabricate the desired component. Initially the cast bucket surface is prepared, for example, by glass sandblasting, chemical etching and possibly nickel plating, followed by a suitable vacuum diffusion heat treatment. The preformed tubing of appropriate size and composition is then vacuum brazed into the cast-in channels in such a manner that both ends of the tubing extend significantly external to the airfoil portion of the bucket.
Thereafter the sheet cladding is formed to the shape of the substrate on a mandrel or master shape as for example by the method disclosed in Schilling, et. al. U.S. Pat. No. 3,928,901 and assigned to the assignee of the present invention and incorporated herein by reference. Briefly described, this method comprises the steps of: rough forming the sheet cladding to the master shape so that the sheet cladding closely abuts the convex surface of the master shape while the sheet cladding opposite the concave surface of the master shape is spaced from the concave surface; placing the sheet cladding and master shape in a sealed rubbery mold; and, applying isostatic pressure to the mold to deform the sheet cladding into contact with the master shape concave surface.
After the formed sheet cladding and substrate with brazed-in tubes are assembled, the assembly is further prepared by masking all seams which are defined between the cladding sheet and substrate to prevent penetration by the pressure transmitting medium into the interface between the cladding and substrate. The masking step may be carried out by taping the seams or by tack welding the cladding sheet to the substrate along the seams. Brazing is another method which could be used during the masking step. All that is required is that some step by taken to keep the pressure transmitting medium, whether it is in the solid, gaseous or molten state, from entering the cladding-substrate interface.
The masked assembly is then inserted into a metal container and filled with glass beads or chips such that upon heating above the melting temperature of the glass, the assembly will be immersed in the molten glass and the upper portion of the tubing will extend about 2-3 inches above the glass level. Glass is preferred as a pressure transmitting medium because the glass will densify and become molten at diffusion bonding temperatures to provide an optimum hydrostatic pressure transmitting medium. Moreover, glass is relatively inert, and can be easily removed from the surface of the assembly upon solidification after the diffusion bonding step.
The loading container is then placed into a vacuum retort furnace and a dynamic vacuum of about 5 μm Hg is applied. While under vacuum, the temperature of the retort is raised, for example, to about 600° F. (315° C.) in order to outgas the glass and the part. After an appropriate hold time, the retort is backfilled with either argon or nitrogen and the temperature raised to the desired bonding temperature. During this sequence, the glass chips become molten, flow and coat the entire part except the tops of the tubing which extend 2-3 inches above the tip of the part. The loaded container is removed hot from the retort and placed in a hot isostatic press (autoclave) which is set at the desired bonding temperature. The autoclave is sealed and pressure applied. During the bonding step, molten glass is prevented from entering the interfacial areas due to the pressure of the masking material and the tubing does not collapse under the applied pressure because it is open to the autoclave atmosphere. Temperatures and pressures used during the diffusion bonding step are dependent upon the materials which are bonded. FIG. 6 shows a typical time, temperature and pressure curve for a diffusion bonding cycle.
Thereafter, the bonded assembly is removed from the container and glass which has adhered to the surfaces of the assembly is removed by sandblasting or by subsequent vacuum heating and water quenching of the assembly. At this point, the bonded clad-substrate assembly may be subjected to a final heat treatment, if required. Our invention is further illustrated by the following example:
EXAMPLE
A schematic representations of the turbine bucket in the apparatus used herein is shown in FIG. 3.
An IN738B, MS5001 first stage bucket 42 was obtained in the as-cast condition with a completely solid airfoil 42. A channel approximately 0.15 inches wide × 0.15 inches deep was electrodischarge machined over the entire length of the airfoil 42 on the pressure (concave) face. After machining, the entire airfoil 42 was cleaned by glass bead blasting and degreased.
After cleaning, a 12" length of OFHC copper tubing 44 (1/8" O.D.×0.090" I.D.) bent in a "U" shape as placed in the airfoil channel as shown and above the platform 43 in a manner such that both ends of the tubing extended about 3 inches above the tip of the airfoil. The tubing 44 was held in place by strips of Nichrome sheet which were spot welded to the airfoil. The copper tubing was brazed into the airfoil with a brazing alloy 46, "Nicrobraze 10," at about 1700° F. (927° C.). Subsequent to brazing, the excess braze alloy was removed by grinding.
A 2"×3" sheet of 0.015" thick annealed OFHC copper 48 was placed over a section of the brazed-in tubing and hand formed over it to match the concave radius of the airfoil 42. After forming, the copper sheet was cleaned by etching in dilute nitric acid. A sheet 50 of Hastelloy X approximately 21/2×31/2" by 0.007" thick which had been cleaned by abrading and degreased was placed over the copper sheet 48 such that a 1/4" overlap resulted on all sides. The Hastelloy X sheet 50 was spot welded directly to the airfoil surface and the edges covered by masking 52.
The entire assembly was placed in a stainless steel can 40 and soda-lime glass chips were added to a level which would cover the airfoil but not the tops of the tubing 44, when during heating the chips become transformed to a molten glass 54. The can 40 with contents was placed in a retort and evacuated to a dynamic vacuum of about 5 μm Hg for about 3 hours. During this period the temperature of the retort was raised to about 600° F. (315° C.) in order to facilitate the outgassing cycle. After the hold period, the retort was backfilled with argon gas 56 to atmospheric pressure and the temperature raised to 1600° F. at which temperature the can assembly was allowed to soak for one hour.
After the additional one hour hold, the can 40 was removed from the retort and placed in a hot isostatic press (autoclave) which was idling at 1600° F. (871° C.). The autoclave was then sealed and pressurized to 5,000 psi and held at temperature and pressure for one hour. After bonding the autoclave was depressurized and the parts removed at 1600° F. (871° C.). The diffusion bonding was performed in accordance with the pressure-temperature-time curve shown in FIG. 6.
Excess glass was removed from the airfoil section of the bucket 42 by sandblasting. A transverse section of the airfoil was mounted and metallographically prepared. It was observed that the copper tubing 44 remained open and had not collapsed. This may be explained by the fact that its internal pressure was at equilibrium with the applied autoclave pressure. At 5,000 psi and 1600° F. (871° C.) the copper tubing 44 was actually extruded into a void in the area filled with braze alloy 46. Excellent bondline quality was obtained for the Hastelloy X/Cu and Cu/IN738B interfaces.
It is apparent that the configuration shown in FIG. 3 and used in the example, wherein "U" tube exits above the bucket platform, does not result in a bucket having tubes located as shown in FIG. 1. It will be appreciated, however, that the desired configuration can be achieved by simply drilling holes of appropriate diameter and location in the platform 43 and passing the pressurized tube through the hole and brazing it in place. This is shown schematically in FIG. 4, wherein like parts are designated by the same numerals as those of FIG. 3. The unwanted sections of the tube would then be machined away after the bonding cycle.
Similarly, FIG. 5, wherein like parts are designated by the same numerals as those of FIG. 3, illustrates another modification. Thus, the pressurized tube could be brazed in a prelocated, drilled hole which does not completely penetrate the cross-section of the platform 43, and then bonding the cladding. Final drilling of the hole to the desired size may then be accomplished from the dovetail side of the platform.
A further embodiment of the invention is illustrated in FIG. 7, which shows a turbine nozzle 60 made by the same process and having similar structural elements as those depicted in the turbine bucket 10 of FIG. 1. The core 66 of the nozzle 60 has a multiplicity of radial grooves 18 either cast or machined into the surface thereof. Into these grooves 18 are fitted preformed cooling tubes 20 which are bonded to the core 66 by means of a braze 32 applied by a standard brazing technique. The composite skin 22, preferrably in contact with a portion of the cooling tubes 20, is composed of the inner layer 23 which is highly heat conducting, such as copper or a copper containing material, and the outer corrosion resistant skin 24. An enlarged cross-sectional view of the structure of the nozzle 60 in the proximity of the cooling tube is similar to the structure shown in FIG. 2.
A schematic representation of the turbine nozzle 60 in an apparatus used in this invention is shown in FIG. 8 which is almost identical to the representation shown in FIG. 3 for the turbine bucket. Thus for the nozzle the copper tubing 44 bent in a "U" shape is placed in nozzle channels as shown in such a manner that both ends of the tubing 44 extends about 3 inches above the nozzle. The tubing was held in place with Nichrome strips which were spot welded to the nozzle. The copper tubing 44 was brazed into the nozzle 60 with a brazing alloy 46. Thereafter a 0.015" thick copper sheet was placed over a section of the brazed-in tubing and conformed to the shape of the nozzle to form the inner layer 48. A Hastelloy X sheet 50 was spot welded directly to the surface of the nozzle 60 and the edges covered by masking 52.
The entire assembly was placed in a stainless steel can 40 and soda-lime glass chips were added to a level which during heating would cover the nozzle 60, but below the tops of the tubing 44 when the chips become transformed to a molten glass 54. The diffusion bonding including the presence of argon gas 56 and is performed according to the pressure-temperature-time curve shown in FIG. 6.
It will be appreciated that the invention is not limited to the specific details shown in the examples and illustrations and that various modifications may be made within the ordinary skill in the art without departing from the spirit and scope of the invention. | A method of fabricating complex, composite components for water-cooled, high temperature gas turbines is provided. The method utilizes hot isostatic pressure with molten glass as a pressure transmitting medium. Metal tubing and cladding are bonded to a component core under conditions such that the ends of the tubing extend above the molten glass whereby the pressure inside and outside of the tubing is maintained at equilibrium to prevent collapsing thereof during the application of hot isostatic pressure. | 8 |
This application is a division of application Ser. No. 08/412,442, filed Mar. 29, 1995, now U.S. Pat. No. 5,543,348.
BACKGROUND OF THE INVENTION
1. Technical Field
The present invention generally relates to a method of manufacturing a semiconductor memory device and, more particularly, to a method of forming a buried strap for electrically connecting a storage trench capacitor to a transfer gate in a trench-capacitor type DRAM cell.
2. Description of Related Art
FIG. 1 is a circuit diagram of a conventional memory cell 10 used in a dynamic random access memory (DRAM). Memory cell 10 includes a storage capacitor 15 for storing charges and a MOS transfer transistor (or "transfer gate") 20 for controlling charge transfer. One end of the source-drain path of MOS transistor 20 is connected to bit line BL and the other end of the source-drain path of MOS transistor 20 is connected to a first electrode of capacitor 15. A second electrode of capacitor 15 is connected to a predetermined potential such as ground potential. The gate of MOS transistor 20 is connected to word line WL to which signals are applied for controlling the transfer of charges between storage capacitor 15 and bit line BL, thereby reading and writing data. While it is desirable to increase the integration density of memory cells on a memory chip by making the MOS transfer transistor and the storage capacitor smaller, the capacitor must nonetheless be large enough to store sufficient charge for ensuring that data is correctly read from and written to the memory cell. So-called trench capacitors have been developed to increase the capacitance of the storage capacitor while permitting the integration density of the memory cells to be increased.
Various techniques have been employed to connect trench capacitors to surface-located transfer gates. For example, a self-aligned buried strap as described, in Nesbit et al., A 0.6 μm 2 256Mb Trench DRAM Cell With Self-Aligned BuriEd STrap (BEST), IEDM 93-627-630, may be used. FIGS. 2A and 2B illustrate the DRAM cell and buried strap described in the Nesbit et al. publication. Specifically, FIG. 2A illustrates a top-down view of a DRAM cell having a self-aligned buried strap and FIG. 2B is a cross-sectional view taken along line I-I' of FIG. 2A. DRAM cell 50 includes a trench capacitor 55 and a transfer gate 60. Trench capacitor 55 includes a first N+ polysilicon fill 65, a second N+ polysilicon fill 67, and a collar oxide 71. Transfer gate 60 includes N-type source/drain regions 73 and 74 formed in a P-well 75 and a polysilicon gate 77 insulatively spaced from the channel between source/drain regions 73 and 74. A bit line contact 79 electrically connects source/drain region 73 to bit line 81. A shallow trench isolation (STI) arrangement 80 electrically isolates DRAM cell 50 from an adjacent memory cell and passing word line 92. A diffusion region 83 is formed to electrically connect third polysilicon fill 69 and source/drain region 74 of MOS transfer gate 60 by outdiffusing dopants from the highly doped polysilicon fill in the storage trench into the P-well 75. Diffusion region 83 and third polysilicon fill 69 constitute a buried strap for connecting trench capacitor 55 to transfer gate 60.
However, several difficulties are associated with the buried strap concept. A first difficulty is that after the buried strap is formed, the thermal budget of the further semiconductor device fabrication process is limited. Exceeding this limit leads to an excessive outdiffusion from the trench polysilicon fill to underneath the transfer gate and towards neighboring memory cells. This dopant outdiffusion results in unacceptable changes of the transfer gate device characteristics as well as in possible electrical leakage between neighboring cells. With the shrinking design groundrule of high capacity DRAMs, the tolerable length of this outdiffusion also decreases. For example, in a 256 Mb Trench Capacitor DRAM cell with a 0.25 micrometer design groundrule and with the buried strap concept, only a 0.1 micrometer outdiffusion from the side of the trench is allowed.
Further, the limitation on the thermal budget after buried strap formation limits oxidation steps to low temperature and conflicts with the need for thermal anneals to heal implantation damage or to relieve stress built up in the silicon substrate during the fabrication process. During oxidation processes following the buried strap formation, oxygen can diffuse from the substrate surface into the collar oxide and oxidize the sidewalls of the polysilicon trench fill and the substrate as shown in FIG. 3. The collar oxide expands and forms a vertical bird's-beak-shape. This collar expansion leads to a high stress level and to generation of extended crystal defects in the substrate like dislocations and stacking faults around the most expanded part of the oxide collar. Extended crystal defects can cause electrical leakage across junctions. If the stress built up during one or several oxidation steps is below the critical level to generate crystal defects, and if there is enough thermal budget to relieve this stress by thermal anneals after the oxidation steps, the formation of extended crystal defects can be prevented. Therefore, a thermal budget which allows proper stress relief anneals is essential for a successful fabrication of a DRAM with the deep trench and buried strap concept.
Another difficulty related to the buried strap concept is the generation of extended crystal defects at the interface of polycrystalline trench fill 69 to the crystalline silicon substrate. This interface sits next to the area where the oxide collar expands most during the oxidation steps of the fabrication process and therefore is exposed to the highest stress field. During the oxidation steps, the polysilicon trench fill 69 contacting the single-crystalline silicon substrate starts to recrystallize in an uncontrolled manner over a distance which can be as far as the width of the collar oxide. Due to the inherent high stress field, crystal defects in the polysilicon grains (twins, stacking faults, etc.) act as seeds for defect formation at the interface to the neighboring substrate. Crystal defects are generated there and pushed far into the substrate.
SUMMARY OF THE INVENTION
In accordance with the present invention, a method of forming a coupled capacitor and transistor is provided. A trench is formed in a semiconductor substrate and an impurity-doped first conductive region is then formed by filling the trench with an impurity-doped first conductive material. The impurity-doped first conductive region is etched back to a first level within the trench. An insulating layer is then formed on a sidewall of the potion of the trench opened by the etching back of the impurity-doped first conductive region and a second conductive region is formed by filling the remainder of the trench with a second conductive material. The insulating layer and the second conductive region are etched back to a second level within the trench and an undoped amorphous silicon layer is formed in the potion of the trench opened by the etching back of the insulating layer and the second conductive region. The undoped amorphous silicon layer is etched back to a third level within the trench. The undoped amorphous silicon layer is then recrystallized. Impurities are subsequently outdiffused from the impurity-doped first conductive region to the semiconductor substrate through the recrystallized silicon layer. A source/drain region of the transistor is formed adjacent to an intersection of the trench and the surface of the semiconductor substrate. The outdiffused impurities and the recrystallized silicon layer constitute a buried strap for electrically connecting the first and second conductive layers in the trench to the source/drain region.
In accordance with the buried strap recrystallization described above, an additional thermal budget of, for example, at least 90 minutes at 1050° Celsius is achieved. This additional thermal budget can be used for appropriate stress relief anneals without resulting in any excessive dopant outdiffusion from the trench. In addition, the interface of the polysilicon and the single crystal silicon is moved away or recessed from the high stress area around the expanded collar oxide. This avoids the generation and extension of crystal defects into the semiconductor substrate.
These and other features and advantages of the present invention will be better understood from a reading of the following detailed description in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a circuit diagram of a conventional DRAM memory cell.
FIGS. 2A and 2B are top-down and cross-sectional views, respectively, of a DRAM cell with a self-aligned buried strap.
FIG. 3 illustrates the expansion of collar oxide 71 due to oxidation processes after buried strap formation.
FIGS. 4A-4H illustrate the method of forming a semiconductor device in accordance with the present invention.
FIG. 5 is a detailed illustration of the recrystallization of undoped amorphous silicon layer 107.
FIGS. 6A and 6B illustrate defects which are constrained in the trench fill and which extend into the semiconductor substrate, respectively.
FIGS. 7A and 7B respectively illustrate buried straps formed in accordance with the method of the present invention and in accordance with a prior art method, respectively.
DETAILED DESCRIPTION
The present invention will be described in detail with reference to FIGS. 4A-4H. As shown in FIG. 4A, a buried N-type well 100 is formed in a P - -type semiconductor substrate 10 by implanting phosphorous below the intended P-well for a memory cell array. A buried N-type well may also be formed by other methods, e.g., P-well implantation into an N-type semiconductor substrate or by epitaxy, and the invention is not limited in this respect. A silicon nitride layer 102 of about 0.2 micrometers is formed by chemical vapor deposition, for example, on the surface of a thin oxide layer 101 (e.g., about 10 nanometers) which is thermally grown on semiconductor substrate 10. Oxide layer 101 and silicon nitride layer 102 are patterned and etched to provide a mask for etching a trench 103. Trench 103 is etched using an anisotropic etching process to a depth of about 8 micrometers as shown in FIG. 4B. After storage node trench 103 is etched, an N + -type capacitor plate 104 is formed by outdiffusing arsenic from the lower portion of trench 103. An oxidized nitride (ON) storage node dielectric (not shown) is then formed in trench 103. After the dielectric is formed, a first conductive region is formed by filling trench 103 with an impurity-doped first conductive material such as N + -type polycrystalline silicon. The filling step may be carried out using chemical vapor deposition of silane or disilane, for example. The N + -type polycrystalline silicon is then etched back to a first level within trench 103 using an isotropic etch process to form a first trench fill 105. The level of first trench fill 104 is about 1.0 micrometer below the surface of semiconductor substrate 10. A collar oxide 106 is then formed on the sidewall of the portion of trench 103 opened by the etching back of the N + -type polycrystalline silicon using LPCVD or PECVD TEOS as shown in FIG. 4C.
A second conductive region is formed by filling in the remainder of trench 103 with a second conductive material. The second conductive material may be, for example, N + -type polycrystalline silicon or undoped polycrystalline silicon and may be formed by chemical vapor deposition. The second conductive material and the oxide collar 106 are then etched back to a second level within trench 103 to form a second trench fill 107 insulated from the semiconductor substrate by oxide collar 106 as shown in FIG. 4D. The depth of the buried strap to be formed in a subsequent process step is defined by this controlled etch-back of the second conductive material and oxide collar 106. Second trench fill 107 is etched back to about 0.1 micrometer below the surface of semiconductor substrate 10. An in-situ removal of a native oxide in trench 103 is then performed. In particular, it is important that a native oxide on the upper surface of second trench fill 106 and on the sidewall of trench 103 through which impurities for the buried strap will subsequently be outdiffused are removed. This removal of native oxide may be carried out by an in-situ prebake in a hydrogen ambient at a temperature greater than 850° Celsius, for example.
The portion of trench 103 opened by the etching back of oxide collar 105 and the second conductive material is then filled by amorphously depositing undoped silicon using chemical vapor deposition, for example. Although the amorphous silicon may be doped, this silicon will act as a diffusion barrier for dopants in the deep trench fill as will be explained below and is more effective in performing this function if undoped. The undoped amorphous silicon is then etched back using reactive ion etching, for example, to form a third trench fill 108 as shown in FIG. 4E. The amorphous silicon is preferably etched back to about 0.05 micrometer below the surface of semiconductor substrate 10 as determined by the tolerable resistance of the buried strap, and by the recess etch controllability. As will be discussed below, the recrystallization of third trench fill 108, as an extension of the buried strap, can be accomplished in a controlled manner if the undoped silicon is deposited amorphously. With reference to FIG. 4F, a reactive ion etch is performed to provide shallow trench 110 for shallow trench isolation. In general, shallow trench isolation is used to isolate discrete memory cell devices to prevent interference therebetween. Accordingly, a shallow trench such as shallow trench 110 is formed between adjacent deep trench configurations to ensure that they operate independently.
Then, the undoped amorphous silicon layer 108 is recrystallized as shown in FIG. 4G and in more detail in FIG. 5. The recrystallization is performed by heating at a temperature at which the amorphous silicon layer 108 begins to recrystallize, but at which the spontaneous formation of polysilicon is still prevented. A typical recrystallization temperature is around 550° C. and a typical temperature range for recrystallization is between about 500° and 700° C. The recrystallization rate of amorphous silicon depends exponentially on temperature: the lower the temperature, the longer the process time.
The extension of the recrystallized area is determined by the depth of the amorphous silicon layer 108. Because recrystallization simultaneously starts at the interface of amorphous silicon layer 108 and the substrate and at the interface of second conductive region 107 and amorphous silicon layer 108, a single crystalline area without any defects will be formed in the hatched area of FIG. 5. The dotted area in FIG. 5 contains polycrystalline grains. The diagonal line in between these two areas indicates the interface at which the recrystallizing front and the polysilicon front meet. Because the crystalline silicon substrate acts as a seed for the recrystallization, a native oxide in between the substrate and the amorphous silicon layer 108 as well as a native oxide in between second conductive region 107 and amorphous silicon layer 108 is not acceptable. Therefore the in-situ removal of the native oxide prior to deposition of the amorphous silicon as described above is important.
It is important to recrystallize the silicon layer 107 before the first oxidation process is performed. Only in this case is the interface of the poly-/single-crystalline silicon moved away from the high stress area around the expanded collar oxide. The recrystallization step can be easily integrated in the fabrication process if, for example, prior to a subsequent shallow trench isolation (STI) oxidation step, wafers are placed in a furnace at, for example, 550° C. and kept at this temperature under nitrogen ambient for some minutes (e.g., 10 minutes). As noted above, recrystallization time depends exponentially on temperature. The recrystallization time is also dependent on the quality of the amorphously deposited silicon.
Shallow trench 110 is then filled in to ensure isolation from adjacent trench structures. For example, with reference to FIG. 4H, an oxide lining 120 may be formed over the layer 107 and the interior surface of shallow trench 110. A nitride lining 122 may then be formed over oxide lining 120. The oxide and nitride linings 120, 122 serve to isolate collar oxide 105 from oxidant, and thereby suppress dislocation and stress. Finally, shallow trench 110 may be filled according to techniques known in the art. For example, an oxide 124 may be deposited to fill in shallow trench 110.
Other shallow trench isolation techniques may be used such as the technique described in U.S. application Ser. No. 08/351,161 entitled "Shallow Trench Isolation with Deep Trench Cap", which is incorporated herein by reference thereto.
During the complete DRAM fabrication process, impurities from the conductive regions within the trench are outdiffused to form strap portion 126. By virtue of the recrystallizing step described above, an additional thermal budget results, whereby stress relief anneals can be performed without the outdiffusion affecting the transfer gate characteristics or adjacent memory cells. These stress relief anneals are preferably carried out after oxidation steps which generate stress in the substrate (e.g., sacrificial gate oxide, gate oxide), or after ion implantation. In addition, since the interface of the poly/single crystalline silicon is moved away from the high stress area around the oxide collar, the generation and extension of crystal defects into the substrate is reduced.
A gate insulator may then be formed on the planar surface, and gate material may be deposited and patterned to form gate electrodes. Using the gate electrodes as masks, source/drain regions may be formed by ion implantation. Accordingly, transfer gates coupled to trench capacitors are realized. Interconnection between devices and metallization to the output terminals are conducted using techniques known in the art.
In accordance with the present invention, a simple, process-compatible method is provided for fabricating a diffusion-limiting interconnection between the polysilicon fill of a deep trench capacitor and the semiconductor substrate before a buried strap is outdiffused. This interconnection consists of undoped crystalline silicon of a defined width which has been formed by a controlled recrystallization of the upper part of the deep trench fill. An additional thermal budget is then given to allow proper stress relief anneals in the fabrication process of DRAM cells with deep trench and buried strap.
The generation of extended defects in the silicon substrate is also prevented since the interface of the polysilicon trench fill and the crystallization substrate is recessed towards the trench fill, away from the high stress area around the upper collar oxide. Even if some defects like stacking faults or twins which lie on the {111} crystal planes are generated in the recrystallized part they are substantially constrained there because of geometrical reasons and do not extend into the substrate. Specifically, with reference to FIG. 6A, stacking faults and dislocations mostly lie on (111) crystal planes in the single crystalline silicon, i.e., under approximately 55° relative to the substrate surface. If the defect generating polysilicon/crystalline silicon interface is pulled back, then defects which originate at this interface have less probability of extending into the substrate. Defects which are confined within the third deep trench fill do not cross any electrical junctions, and therefore do not cause leakage.
With reference to FIG. 6B, for the case where the interface is not recessed by a recrystallization, originating defects would always extend into the substrate.
Thus, the controlled recrystallization of the upper part of the trench fill recesses the single/poly-crystalline interface behind the expanded collar oxide, thereby avoiding the generation and extension of crystal defects into the substrate, while simultaneously solving the problem of the limited thermal budget. The additional thermal budget gained by the buried strap recrystallization can be seen from FIGS. 7A and 7B. The outdiffusion of the buried strap is simulated for two cases. The first trench fill is assumed to be doped with (As) 5×10 19 cm -2 and the second and third trench fills are assumed to be undoped. The p-well doping around the trench is (B) 2×10 17 cm -2 . FIG. 7A shows a trench with a recrystallized buried strap. The simulation is based upon the thermal budget for the fabrication process (which does not include any stress relief anneals) plus an additional thermal budget for stress relief of, for example, 90 minutes at 1050° C. Of course, 90 minutes at 1050° is merely exemplary of the additional thermal budget which may be gained in accordance with this invention. The Dt product (D=temperature dependent diffusion coefficient of outdiffusing dopants, t=diffusion time) allows longer times at lower temperatures, or shorter times at higher temperatures. As can be seen with reference to FIG. 7A, the outdiffused buried strap overlaps the source/drain region so that good contact is guaranteed. The junction width of the buried strap to the P-well is below 0.1 micrometer so that there is no effect on the transfer device characteristics. Further, there is no chance of electrical leakage to the buried strap of neighboring cells.
FIG. 7B shows an identical structure, simulated with the same thermal budget as in FIG. 7A, but without buried strap recrystallization. The buried strap outdiffusion of about 0.15 micrometers may already influence the transfer device characteristics. In this structure, a perfect overlay alignment of the transfer gate to the trenches is assumed. However, if the overlay of the transfer gate to the trench deviates from the perfect alignment position up to its maximum permitted value of 0.1 micrometer, the outdiffused buried strap reaches underneath the transfer gate. The electrical characteristics of the transfer device will be strongly affected. Also the possibility of cell-to-cell leakage via buried straps of neighboring cells is much higher than in the case without buried strap recrystallization.
The simulations show clearly that with the buried strap recrystallization, a much higher thermal budget of the fabrication process is allowed. The additional thermal budget of, for example, at least 90 minutes at 1050° C. which is gained by the controlled recrystallization of the third trench fill, can be used for appropriate stress relief anneals without any excessive dopant outdiffusion from the trench.
While the invention has been described in detail with reference to the appended drawings, the invention is limited in scope only by the claims. Moreover, any publication cited herein should be construed to be incorporated by reference as to any subject matter deemed essential to the present disclosure. | A semiconductor memory device includes a trench formed in a semiconductor substrate. Conductive material is formed in the trench and is insulatively spaced from the semiconductor substrate to form a capacitor. A transfer gate transistor includes source/drain regions formed on a surface of the semiconductor substrate and a control gate which is insulatively spaced from a channel region between the source and drain regions. A buried strap electrically connects the capacitor to one of the source/drain regions of the transfer gate transistor. A portion of the buried strap includes recrystallized silicon. | 7 |
BACKGROUND OF THE INVENTION
Object of the present invention is an apparatus for the vaporization of fuels comprising a nozzle unit supplied via a fuel pump and fuel supply line with fuel and, separately, via an air generator and air supply line with air, said nozzle unit having a longitudinal axis and a chamber mounted perpendicularly to said axis into which the fuel and air are conveyed for mixing via supply lines, the supply lines for the fuel opening tangentially into the chamber so that the fuel in the chamber is set in whirling motion occurring substantially in a direction perpendicular to the longitudinal axis, and the mixture being discharged via a nozzle channel.
The combustion of organic matter such as fuel oil gives rise to the formation of residues such as carbon monoxide (CO), which burns to carbon dioxide (CO 2 ), hydrogen, which is oxidized to water vapor, and nitrogen monoxide (NO), which with air oxygen is oxidized to NO 2 , together known as NO x .
Apart from the hydrocarbons and other ingredients, fuel oils contain chlorine and sulfur, the share of the latter being higher the heavier the fuel oil and attaining up to 3.5% by weight.
The main problem of present heating installations is that of particle size of the atomized fuel oil, which to the extent of 80% is between 40 and 80 microns when an atomizing pressure of about 15 bars is used.
For optimum combustion the relatively large droplets are maintained in suspension by means of a blower until they have completely burned, but this leads to oversized combustion chambers, on one hand, and to overly large air volumes per kilogram of the fuel oil, on the other hand.
Particularly in the case of industrial oil burners, good combustion is difficult to attain since the known mechanical spray diffusers, with the heavy fuel oils used here, lead to a particle size of at least 60 microns even at high pressures, of over 20 bars. In addition, very small nozzle openings are required here, with a diameter of about 0.15 mm, which readily clog and cause breakdowns.
The heavy fuel oils are heated to temperatures of 50° to 100° C. in order to lower their viscosity, which has an effect on particle size, though not enough to bring about an optimum combustion, quite apart from the fact that a large amount of energy is consumed for heating the fuel oil.
The amount of air of combustion which is supplied, but also its pathway within the burner and its temperature are decisive, too, for the combustion process, the amount of air usually being exaggerated and never merely that required stoichiometrically, since with the stoichiometric amount alone the unburned residues would be overly large.
The excessive production of NO X is a real problem which, when combustion is incomplete, with hydrogen and water vapor leads to the formation of sulfuric, hydrochloric and nitric acid leading to the well-known acid rain.
DESCRIPTION OF THE PRIOR ART
French Patent No. 903 293 describes an apparatus having the characteristics stated in the introduction to claim 1. The apparatus comprises a nozzle unit with concentrically arranged supply lines for fuel and gas opening via tangentially oriented channels into a whirling chamber from which the fuel-gas mixture is discharged via a nozzle channel. Here, both the gas and fuel are fed tangentially into the chamber, where they are in whirling motion. As the gas and fuel move in the same sense, and more or less parallel one besides the other, this arrangement cannot produce a thorough mixing of fuels and gas, which has a negative effect on particle size at the exit and excludes an optimum combustion.
According to French Patent No. 809 455, the fuel and air are conveyed together to the discharge channel over helicoidal grooves in the nozzle unit. Even here, the mixing of fuel and air is only moderate. Moreover, means are not provided here for producing higher compression of the air in the fuel, which is very important for fuel vaporization.
SUMMARY OF THE INVENTION
The present invention has the objective of obviating the disadvantages of known apparatus, and vaporize rather than atomize the fuels, while attaining the smallest possible particle size.
According to the invention, this objective is attained by an apparatus for the vaporization of fuels and supply of air for combustion as defined in claim 1.
In the apparatus according to the invention, the air used for vaporization thus constitutes part of the air for combustion, while an ultrafine particle size leads to faster vaporization and thus better combustion, so that the formation of undesired residues and particularly of NO X is limited.
Further advantages will become apparent from the characteristics of dependent claims and from the following description illustrating the invention in detail and with advantageous, though not limiting embodiments with the aid of drawings where
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a sectional view of a two-component nozzle according to the invention,
FIG. 2 is a sectional view of a nozzle core along sectional plane 2--2 of FIG. 1,
FIG. 3 is a sectional view of a nozzle sleeve along sectional plane 2--2 of FIG. 1,
FIG. 4 is a sectional view of a nozzle sleeve according to FIG. 1,
FIG. 5 is a sectional view of another embodiment of a two-component nozzle according to the invention,
FIG. 6 is a sectional view along sectional plane 6--6 of the nozzle sleeve of FIG. 5,
FIG. 7 is a sectional view along sectional plane 6--6 of the nozzle core of FIG. 5,
FIG. 8 is a schematic representation of the operating principle of the apparatus according to the invention,
FIG. 9 is a partly sectional top view of an extremely advantageous embodiment of the apparatus according to the invention, and
FIG. 10 is a schematic front view of the apparatus of FIG. 9 showing the distribution of secondary air of combustion and a possible recirculation of the fumes.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Fundamentally, the apparatus of the present invention is based on a device for atomization of liquids mixed with compressed gas which, at a pressure of merely 1 bar, gives rise to a Sauter mean particle size of 21.08 microns. Depending on the amount of admixed air and on the cross section of the nozzle opening 9, the particle size can be reduced considerably, so that the operation can be called vaporization.
This vaporization constitutes the basis of the apparatus according to the present invention and guarantees an optimum combustion.
FIG. 1 shows a nozzle sleeve 1 holding a nozzle core 2 with a mixing chamber 3 receiving compressed air via bores 4 parallel to the core axis and fuel oil under pressure via supply channels 5 and tangential channels 6 (see also FIG. 2) so that the fuel oil and compressed air can mix in it. The nozzle sleeve 1 has an expansion chamber 7, a compression chamber 8, and a nozzle channel 9. The depth of expansion chamber 7 and compression chamber 8 is determining for the length of nozzle channel 9, a short nozzle channel 9 providing a wider cone than a long channel.
FIG. 4 further shows a conical nozzle channel 10 providing an even wider cone than a nozzle channel 9 that has equal length but is cylindrical. The diameters of nozzle channels 9 and 10 are determining for the amount of fuel oil delivered in unit time; at any given pressure, this delivery is small for low channel diameters, but the diameters of nozzle channels 9 and 10 are not below 0.30 mm, and they remain always permeable, since they can be purged with the air of vaporization.
The supply channels 5 of nozzle core 2 open into the tangential channels 6 which in turn open into the mixing chamber 3, hence a fuel oil coming from the supply channels 5 and tangential channels 6 is injected into the mixing chamber 3 in such a way that it is set in whirling motion along the chamber walls while the compressed air is fed in perpendicularly via bore 4, passes through a first phase of compression in the mixing chamber 3, is allowed to expand in expansion chamber 7 , but is then compressed into the fuel oil in compression chamber 8. Therefore, when the fuel oil-air mixture leaves the nozzle sleeve via the nozzle channel 9, the highly compressed air will expand as if exploding when it comes in contact with atmospheric pressure, hence it shatters the fuel oil into minute droplets, which are so much smaller since the fuel oil and air pressure is high; they have a diameter of less than five microns when the working pressure is between three and five bars. In this way the total surface area of the vaporized fuel becomes exceedingly large, and more air oxygen can be taken up for combustion, which leads to better combustion, hence to a better heating value, so that fuel oil is economized, on one hand, and fewer residues are formed, on the other hand.
FIG. 5 shows another embodiment of a nozzle unit consisting of a nozzle sleeve 11 and nozzle core 12 to be used especially for fuels where the nozzle unit must be adapted precisely to the fuel oil viscosity, as in the instance of heavy fuel oils. Changes would have to be introduced in the supply channels 5, the tangential channels 6 and the mixing chamber 3 of nozzle core 2 as well as in the expansion chamber 7 of nozzle sleeve 1 if the nozzle unit of FIG. 1 had to be adapted to a viscosity of more than ten centipoises. The changes are simpler in the embodiment according to FIG. 5. In this embodiment, supply channels 7 and tangential channels 14 are located in the nozzle sleeve 11, the tangential channels 14 opening into the compression chamber 15 which has the nozzle channel 16. The air is conveyed to the mixing chamber 17 via bores 8, while this chamber is connected to the compression chamber 15. It will suffice to use a deeper mixing chamber 17 in the nozzle core 12 and to enlarge the diameters of the bores in order to adapt this nozzle unit to a higher viscosity.
FIG. 8 shows the operating principle of the device according to the present invention. A pressure vessel 19, preferentially made of duroplast, is tightly sealed with a lid 20 supporting a rotary piston compressor 21 driven by a motor 22. A float 23 with needle 24 is inside the pressure vessel 19. Lid 20 is provided with a relief pressure valve 25 and air vent 26. A fuel oil inlet 27, a fuel oil return pass 28 closed off by the needle 24 temporarily, and a fuel oil vent 29 are located at the bottom of pressure vessel 19. The fuel oil (not shown) is conveyed into pressure vessel 19 via a pump 30 while the compressor 21 creates air pressure in the pressure vessel 19 the pressure level being adjustable via the relief pressure valve 25. Excessive filling of the pressure vessel 19 is avoided by the float 23 pulling needle 24 from the return pass 28 as soon as a predetermined amount of fuel oil is present in pressure vessel 19 hence excess fuel oil flows back to the intake duct of pump 30. The nozzle sleeve 1 (11) with nozzle core 2 (12) is inserted into a manifold 31. This manifold is supplied with compressed air via air vent 26 and a magnetic valve 32, the air volume being adjustable with a needle valve. The fuel oil, which is under the same pressure as the air, is forced into manifold 31 via the fuel oil vent 29 and a magnetic valve 34, the fuel oil volume being adjustable with a needle valve 35. The manifold 31 supports a hollow combustion cylinder 36 provided with a screen 37 in the direction of the nozzle axis and having lateral holes 38 which can be closed off to varying degrees with a slide 39. Secondary air of combustion coming from a blower 40 can be introduced through these lateral holes 38 into the hollow cylinder 36 and thus into the vaporized fuel oil that is already enriched with primary air of combustion.
Compressed air will flow as described into the mixing chamber 3 (17) of nozzle core 2 (12) after opening of the magnetic valve 32 and purge the nozzle channel 9 (16), so that the vaporized fuel oil after opening of the magnetic valve 34 can leave through a "clean" nozzle channel 9(16) and be ignited in the form of a fuel oil-air mixture when mixed with the compressed air coming from the pressure vessel 19.
For full combustion of any CO that might be present, it will be possible to heat screen 37 to about 750° C. so that the CO (which burns to CO 2 at 700° C.) is eliminated from the residues.
Since NO X will decompose to nitrogen and oxygen at 620° C., this can be attained with screen 37.
When it is desired to terminate the combustion process, the magnetic valve 34 is closed first, then only compressed air will pass through nozzle channel 9(16), thus purging it from fuel oil residues.
The relief pressure valve 25 may consist of a membrane raised by a magnet core in an electrical coil when a preselected current flows, at which point the excess pressure is relieved. Such an embodiment when provided with a potentiometer controlling the coil current greatly facilitates adjustment of the pressure level, since a mere change of the current through the coil is required in order to raise or lower the membrane's pressure resistance. It is an important advantage of this solution that the fuel oil flow in unit time can be adjusted continuously via the pressure in pressure vessel 19 while there will be no important change in particle size.
In practice the particle size decreases by about 0.5 microns when the pressure is raised from 1 to 4 bars, while the amount of fuel oil delivered increases from 0.5 to about 1.1 kg/hour at these values of pressure. This provides a possibility for continuous adaptation of the hourly consumption to the weather conditions, e.g., via an external thermostat, so that the time required for combustion can be shortened by raising the amount of fuel oil burned per unit time, which occurs in an automatic fashion through an electronic circuit.
FIG. 9 shows an extremely advantageous embodiment of the device according to the present invention while disregarding any considerations of scale. The main difference relative to the device of FIG. 8 are the nine pipes 41 replacing, in this embodiment, the hollow cylinder 36; the free ends 42 of said pipes are closed off. The pipes 41 have bores 43; a blower 44 supplies compressed air to pipes 41 which is blown into a flame (not shown) through these bores 43. The blow direction of bores 43 can be adjusted in any desired way through a thread 45 allowing the pipes 41 to be screwed into a distributor plate 46, where they can be locked in position by nuts 47, i.e., the air coming from blower 44 can be blown into the flame in the direction of its axis or more or less tangentially to it so that a controlled vorticity can be attained. It is also possible to achieve a combination of axial and tangential blowing. Further, bores 43 of one pipe 41 can be staggered relative to those of another pipe 41.
Two possibilities for fume recirculation are shown in FIG. 9. The body 49 of blower 44 has openings 50 screened from the outside air with a sleeve 51. In one version, the blower draws fumes via a double-walled hollow cylinder 52 and openings 50; together with outside air drawn in by the blower 41, these fumes are then blown by the blower 44 via pipes 41 into the flame (not shown).
In the other version, which is indicated schematically in FIG. 10, the fumes are drawn in via external pipes 53 provided with bores 54 and via the openings 50 of the body 49, and then blown into the flame as described.
It was shown experimentally that the flame is chilled by secondary air of combustion when this is introduced upstream and parallel to the flame axis, thus the thermal vaporization of the fuel oil is diminished and a maximum combustion prevented.
When secondary air of combustion is introduced via pipes 41 as proposed by the present invention, the advantage arises that the cold external air coming from blower 44 is heated up in pipes 41 and hence cannot chill the flame, thus incomplete combustion on account of chilling of the flame, and consequently a lower thermal vaporization of the fuel oil, is avoided.
With secondary air of combustion blown in a direction perpendicular to the flame, it is further possible to shorten the flame, hence the burner volume can be kept small and the heating efficiency increases, particularly so since the ultrafine fuel oil particles generated by nozzle 1 of the present invention will burn very rapidly and need not be kept suspended, as described, by an overly large volume of secondary air of combustion.
It should be stressed here that the diameter of nozzle channels 9 and 16 is at least 0.4 mm, hence these channels will practically never clog, already since nozzle 1 (11) is purged before and after the combustion process. Despite this width of nozzle channels 9and 16 (their cross sections being about seven times larger than those of mechanical spray nozzles), the consumption can be maintained at 0.5 kg/hour, merely an increase in air pressure in the pressure vessel 19 will raise this consumption in a continuous fashion up to 1.1 kg/hour.
In view of these low amounts of fuel oil burned in unit time, a very large market segment so far not properly served can be covered. | Fuel is fed by a feeding pump to a pressurized container. A predetermined amount of fuel is kept constant in the container by a floater which carries a needle for opening and closing a return as required. In the pressurized container the fuel is kept by a compressor under compressed air pressure which may be regulated by a pressure control valve, so that when the valve is opened fuel and air both under the same pressure are pressed into a nozzle unit in which air is highly pressed in the fuel so that when it leaves the nozzle channel it expands in an explosive manner and bursts the fuel into fine droplets. Secondary combustion air from an air generator is blown into the flame perpendicularly to the axis of the flame and fed to the fuel-air mixture. | 5 |
CONTRACTUAL ORIGIN OF THE INVENTION
The United States has rights in this invention pursuant to contract No. W-31-109-ENG-38 between the United States Government and Argonne National Laboratory.
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to high-temperature ionic conductors for solid oxide fuel cells and more particularly to a class of ionic conductors stable at temperatures in the order of 600°-800° C. and which are based on framework structures with net positive or negative charges along channels, tunnels or planes that are large enough to transport an oxide ion or a hydrated proton.
2. Background of the Invention
Solid oxide fuel cells (SOFC's) can become one of the most durable and economical fuel systems for utility and transportation applications. Using solid electrolytes virtually eliminates corrosion reactions and electrolyte losses that are common in liquid electrolyte fuel cells. Furthermore, fuel processing for SOFC's is simpler and less expensive than other types of fuel cells.
Presently, SOFC's operate at temperatures of approximately 1000° C. The requirement of high-operating temperatures to attain adequate conductivity levels limits the number of materials available for SOFC fabrication as most materials become compromised thermally, chemically and mechanically under these high temperature conditions. For example, the conductivity of the commonly used yttrium-stabilized zirconium oxide is 10 -1 ohm -1 cm -1 at 1000 ° C. This conductivity decreases to 4×10 -2 ohm -1 cm -1 at 800° C. Examples of yttria-stabilized zirconia electrolyte use at high temperatures can be found in U.S. Pat. Nos. 4,476,196; 4,476,197 and 4,476,198, wherein the electrolytes facilitate ion transfer in electrochemical fuel cells operating in temperatures exceeding 1000° C. As with the above-mentioned teachings, most fuel cells incorporating yttria-stabilized zirconia also rely on standard materials, such as zirconium-based cermet as constituents for the accompanying electrodes.
Presently known high-temperature electrolytes are oxide ion conductors that transport oxide ions by the vacancy migration mechanism. In the yttrium-stabilized zirconium oxide system, a positive charge deficiency is created by substituting some trivalent yttrium ions for the tetravalent zirconium ions in the cation sublattice. To compensate for the positive charge deficiency, oxide ion vacancies are formed in the oxide sublattice. These vacancies provide the stopping-off points for hopping oxide ions. Aside from zirconium oxide, other presently known oxide ion conductors include CeO 2 , ThO 2 , HfO 2 , and Bi 2 O 3 . All of these host oxides contain various types of dopants to enhance conductivity. When these materials crystallize in the fluorite structure, oxygen ion vacancies can be found in the oxygen sublattice. These vacancies facilitate the mechanism for the hopping of oxides across the electrolyte thereby serving as the conduit for oxide ions through the electrolyte.
Operating a SOFC at more moderate temperatures, such as 600°-800° C., would allow much greater flexibility in engineering the fuel stack because metals could be used as interconnect and gasket materials. This would ultimately reduce the cost and open up new applications. With the present technology, it is not possible to lower the operating temperature of the fuel cell because the electrical resistance of the electrolyte increases exponentially as temperature decreases. To decrease the operating temperature, a new electrolyte is required.
New electrolytes have been discovered to conduct by a different mechanism; i.e. by transport of interstitial ions instead of by vacancy migration. These oxides do not crystallize in the fluorite structure. They have framework structures which feature channels or planes that are large enough to transport an oxide ion or a hydrated proton through them. By creating net positive or negative charges on the framework, interstitial oxide ions (such as O 2- ) or hydrated protons (such as H 3 O 30 ) are able to pass through the channels and/or planes at a high rate.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a class of electrolytes that overcomes many of the disadvantages of prior art arrangements.
It is another object of the present invention to provide a class of electrolytes for transporting ions for use in utility and transportation applications. A feature of the present class of electrolytes is their use at temperatures of between approximately 600°-800° C. An advantage of the present invention is the ability to now incorporate a wider range of materials in the fabrication of solid oxide fuel cells.
Still another object of the present invention is to provide a highly conductive electrolyte at temperatures below 1000° C. A feature of the invention is the incorporation of a new class of ionic conductors consisting of molecular framework structures having channels or planes large enough to accommodate rapid transport of ions. An advantage of the present invention is a high level of ion conductance at relatively low temperatures.
Yet another object of the present invention is its use as electrolytes in fuel cells, sensors or batteries. A feature of the present invention is substituting some of the atoms on the molecular framework structure of the electrolytes with relatively high- or low-valent elements to create a net positive or net negative charge on the lattice. An advantage of the present invention is the electrolyte's ability to attract and shuttle through the molecular framework structure ions such as oxides and hydrated protons.
In brief, the objects and advantages of the present invention are achieved by a solid oxide electrolyte. An ionic conductor comprising molecular framework structures having net positive or net negative charges, or oxide-ion vacancies is utilized. These structures have channels or planes running through them that are large enough to transport ions such as oxide ions or hydrated protons. These molecular framework structures can be selected from, but are not limited to, the group consisting of substituted aluminum phosphates, orthosilicates, silicoaluminates, cancrinites, cordierites, apatites, sodalites, and hollandites.
BRIEF DESCRIPTION OF THE DRAWING
The present invention together with the above and other objects and advantages may best be understood from the following detailed description of the embodiment of the invention illustrated in the drawings, wherein:
FIG. 1 is a crystal structure plot of Anthophyllite, which is a molecular framework structure utilized in the present invention;
FIG. 2 is a crystal structure plot of Apatite, which is a molecular framework structure utilized in the present invention;
FIG. 3 is a crystal structure plot of Cordierite, which is a molecular framework structure utilized in the present invention;
FIG. 4 is a crystal structure plot of Dumortierite, which is a molecular framework structure utilized in the present invention;
FIG. 5 is a crystal structure plot of Garnet, which is a molecular framework structure utilized in the present invention;
FIG. 6 is a crystal structure plot of LaPO 4 (monoclinic), which is a molecular framework structure utilized in the present invention;
FIG. 7 is a crystal structure plot of LaPO 4 (hexagonal), which is a molecular framework structure utilized in the present invention;
FIG. 8 is a crystal structure plot of Nepheline, which is a molecular framework structure utilized in the present invention; and
FIG. 9 is a crystal structure plot of Sodalite, which is a molecular framework structure utilized in the present invention.
DETAILED DESCRIPTION OF THE INVENTION
The new electrolytes of the present invention described herein operate at temperatures ranging from 600°-800° C. to display conductivities higher than presently used solid oxide electrolytes operating at similar temperatures. The invented class of ionic conductors have molecular framework structures featuring channels or planes that are large enough to transport an oxide ion or a hydrated proton through them. When these structures have net positive or net negative charges associated with them, by for example, substituting some atoms on the structures with relatively higher- or lower-valent elements, i.e., doping the material with aliovalent ions, these structures easily accommodate the shuttling of ions through the channels and/or planes.
Conductivity of the partially substituted electrolytes can be measured by ac impedance spectroscopy in either air or in a humidified hydrogen/oxygen cell, the latter serving to mimic fuel cell stack conditions. Also, by measuring the electromotive force between the two electrodes in humidified hydrogen/oxygen and comparing the experimental to the theoretical values, the ionic transference number can be determined as additional assurance that the conductivity occurring is ionic and not electronic as is the case with the "hopping" oxide ion phenomenon found in the prior art. Unity is the theoretical value depicting a one-to-one ion transfer through the electrolyte.
Molecular Framework
Material Types
A myriad of materials can be used as molecular framework structures which contain channels or pores in the crystal structure that are large enough to accommodate ions. Structures associated with apatite [Ca 5 F(PO 4 ) 3 ], cordierite (Mg 2 Al 4 Si 5 O 18 ), berlinite (AlPO 4 ), cristobalite (SiO 2 -AlPO 4 ), and tridymite (SiO 2 -AlPO 4 ) are representative of the framework structures.
A characteristic of framework materials is open channels or planes running parallel to a crystallographic axis that are amenable to rapid ion migration. A crucial element in choosing a molecular framework structure is the "openness" of the channels. Generally, such channels and planes having diameters of about 3 Angstroms (Å) are acceptable. The openness of the channels and planes can be further quantified by counting the number of oxygen atoms in a 1000 cubic Å volume. Table 1 lists the names of exemplary framework structures together with their openness characteristics and with reference to a corresponding FIGURE of the drawing.
TABLE 1______________________________________Structural Types and Openness of Electrolyte MaterialsStructural Formula of Openness, FIG.Type Parent Mineral O.sup.2-, 1000Å.sup.3 No.______________________________________Anthophyllite (HO).sub.2 Mg.sub.7 Si.sub.8 O.sub.22 54.18 1Apatite Ca.sub.5 F(PO.sub.4).sub.3 45.87.sup.a 2Berlinite AlPO.sub.4Cordierite Mg.sub.2 Al.sub.4 Si.sub.5 O.sub.18 46.36 3Cristobalite (SiO.sub.2 --AlPO.sub.4)Dumortierite (Al,Fe).sub.7 O.sub.3 (BO.sub.3)(SiO.sub.4).sub.3 64.29 4Garnet Ca.sub.3 Al.sub.2 (SiO.sub.4).sub.3 57.62 5Framework L LaPO.sub.4 53.88 6(hexagonal)Framework L LaPO.sub.4 42.73 7(monoclinic)Nepheline KNa.sub.3 (AlSiO.sub.4).sub.4 43.66 8Sodalite Na.sub.4 Al.sub.3 Si.sub.3 O.sub.12 Cl 36.76.sup.a 9Tridymite (SiO.sub.2 --AlPO.sub.4)Olivine.sup.b Mg.sub.2 SiO.sub.4 54.59Hollandite BaAl.sub.2 TiO.sub.16 48.81______________________________________ .sup.a Halide ion is included in oxide ion count. .sup.b Included for the sake of comparison. Olivine represents a close approximation to cubic closepacking.
The openness listed in Table 1 for the various electrolyte materials is greater than that of ZrO 2 . Furthermore, most of the materials tested by the inventors and included in Table 1 are more open than the two well-known types of molecular packing, namely hexagonal and cubic close-packing. Cubic close-packing is represented by Olivine in Table 1. The openness desirability is inversely proportional to the openness numbers found in Table 1 so that those compounds which have low numbers in the openness column are more desirable from an ion transport capability standpoint.
AlPO 4 . An example of a molecular framework having channels to accommodate ion flow-through is aluminum phosphate (AlPO 4 ). AlPO 4 is isomorphous with SiO 2 and has similar phases and structures as silica. In three of these structures, berlinite, cristobalite and tridymite, there is a central channel of about three Angstroms (Å) in diameter which is large enough to accommodate either an O 2- or H 3 O 30 ion. In native AlPO 4 , the channel is unoccupied and the conductivity of aluminum phosphate is very low. Substituting some of the aluminum or phosphorus with a higher-valent element, such as silicon or titanium, leads to either the formation of interstitial oxide ions or free ions. These same effects would be seen when substituting some of the phosphorous with hexavalent sulfur (as sulfate ion) or heptavalent chlorine (as perchlorate ion). Generally, with such substitutions, a net positive charge is put on the framework. This positive charge can be compensated by oxide ions in the channel.
Similarly, by substituting a lower-valent element, such as magnesium or zinc for the aluminum or silicon for the phosphorus, a net negative charge is created on the framework that can be compensated by the formation of vacancies or by positive ions in the channel. The formation of vacancies is a manifestation of the principle of le Chatelier wherein the equivalent of oxide ions leave the lattice structure of the oxide molecule to balance any negative charge resulting from substitution by lower-valance cations.
Some of the substituted aluminum phosphates that were used for testing were first made by dissolving aluminum nitrate, the substitute metal nitrate, and ammonium phosphate in water and then precipitating the aluminum phosphate at a controlled pH of 5 to 7. The precipitate was then washed, dried and calcined. Finally, the resulting powder was pressed into pellets that were sintered to better than 90% density at temperatures of 900°-1600° C.
Sulfate ion was incorporated into AlPO 4 by dissolving stoichiometric amounts of aluminum nitrate, aluminum sulfate and monobasic ammonium phosphate in water, drying and calcining at 800° C. overnight. A similar procedure was used to incorporate perchlorate ion.
Some of the AlPO 4 compositions produced are listed in Table 2 below in isoelectronic formalism. This formalism is based on an analogy of AlPO 4 with SiO 2 . In illustrating the isoelectronic formalism, SiO 2 is rewritten as [SiO 2 ][SiO 2 ]. Replacing the first Si 4+ with a lower-valent Al 3+ and keeping the total oxygen content constant would necessitate a negative charge on the fragment to maintain charge balance. This intermediate species is represented as [AlO 2 ] - [SiO 2 ]. Analogously, replacing the remaining Si 4+ atom with P 5+ would produce a fragment with a positive charge on it and would yield [AlO 2 ] - [PO 2 ] + for AlPO 4 .
TABLE 2______________________________________Doped AlPO.sub.4 Compositions.sup.1______________________________________[AlO.sub.2 ].sup.-.sub.0.84 [SiO.sub.2 ].sub.1.68 [PO.sub.2 ].sub.2.52[O.sub.i "].sub.0.84[AlO.sub.2 ].sup.-.sub.0.84 [MgO.sub.2 ].sup.2-.sub.0.16 [PO.sub.2].sup.+.sub.0.84 [ClO.sub.2 ].sup.3+.sub.0.32 [O.sub.i "].sub.0.32[AlO.sub.2 ].sup.- [PO.sub.2 ].sup.+.sub.0.84 [ClO.sub.2 ].sup.3+.sub.0.48 [O.sub.i "].sub.0.64[AlO.sub.2 ].sup.- [PO.sub.2 ].sup.+.sub.0.84 [SO.sub.2 ].sup.2+ 0.24[O.sub.i "].sub.0.16______________________________________ .sup.1 O.sub.i " represents interstitial oxide ion.
In accordance with a feature of the present invention, AlPO 4 doped with silicon on the aluminum site and sulfur on the phosphorus site has conductivities that are several orders of magnitude higher than those of native AlPO 4 . Separately, AlPO 4 that was doped with 12 Mg mole percent exhibited conductivities as high as 3×10 -2 ohm -1 cm -1 .
Cordierite. These compounds have a general formula (Mg,Fe) 2 Al 4 Si 5 O 18 . Three aluminum atoms are in six-coordination and the fourth substitutes for one Si in a ring structure. Together, they produce an AlSi 5 O 18 group. There are channels within the ring structure in which water and other ions could be accommodated. Two compounds containing interstitial oxygen ions were synthesized, and are represented by the following formulae:
Mg.sub.2 Al.sub.4 Si.sub.4.5 P.sub.0.5 O.sub.18.25
and
Mg.sub.2 Al.sub.3.6 Si.sub.5.4 O.sub.18.20
The cordierite compounds were made by reacting stoichiometric amounts of the respective oxides and monobasic ammonium phosphate at 863° C. for 10 hours. Pellets of the compounds were pressed and then sintered at 1200° C. for 18 hours.
Aluminosilicophosphates. Aluminosilicophosphates represent another framework material type that may contain interstitial oxide ions. A formula for this type of compound is AlSi 2 P 3 O 13 . It is hexagonal in structure. This compound was made by solgel processing whereby 0.1 moles of aluminum nitrate and 0.1 moles of monobasic ammonium phosphate were dissolved in a minimum amount of water (approximately 0.8 moles). 0.2 moles of tetraethoxysilane was then added to the mixture, along with a minimum amount of ethanol to make the mixture homogeneous. The reaction mixture was gently heated to make it a gel. The gel was dried at 130° C. and ground into a paste with 0.1 moles of P 2 O 5 in methylenechloride as the grinding medium. The dried paste was then calcined at 1000° C. for six days. X-ray diffraction analysis indicated that the calcined material contained about 80% of the desired compound.
Impedance measurements on this compound were conducted in a humidified H 2 /O 2 cell, so as to mimic actual use conditions, and also as direct current measurements can yield inaccurate conductance values due to electrical polarization. Measurements in H 2 /O 2 yielded a value of 10 -6 ohm -1 cm -1 for conductivity and 0.4 as the ionic transference number.
Apatites. Given the general structural apatite formula of [Ca 5 F(PO 4 ) 3 ], solid solution apatite structures containing lone oxygen atoms have been produced depicted by the general formula Sr 5 .5 La 4 .5 (PO 4 ) 1 .5 (SiO 4 ) 4 .50 O. The lone oxygen atom sits in a central channel along the crystallographic c-axis, free to migrate. The conductivity and ionic transference numbers for this material were measured in a humidified H 2 /O 2 cell (water on both sides), and the results are depicted in Table 3, below:
TABLE 3______________________________________Conductivity and Ionic Transference Data fromSr.sub.5.5 La.sub.4.5 (PO.sub.4).sub.1.5 (SiO.sub.4).sub.4.5 O.Temperature Conductivity Transference°C. ohm.sup.-1 cm.sup.-1 Number______________________________________810 2.08 × 10.sup.-8 0.84706 2.27 × 10.sup.-7 0.83609 7.58 × 10.sup.-9 0.67______________________________________
Another strontium-containing apatite, having the formula Sr 5 (OH)(PO 4 ) 3 , yielded even higher conductivity values. These values are listed in Table 4, below:
TABLE 4______________________________________Conductivity data from Sr.sub.5 (OH)(PO.sub.4).sub.3Temperature Conductivity Tranference°C. ohm.sup.-1 cm.sup.-1 Number______________________________________495 9.26 × 10.sup.-6 0.32578 2.78 × 10.sup.-5 0.42685 7.52 × 10.sup.-5 0.47781 2.58 × 10.sup.-4 0.59______________________________________
Framework L. Framework L has the following, generalized, nonsubstituted formula LaPO 4 . When framework L is doped with 10% Bi, it retains its hexagonal-to-monoclinic transition at low temperatures, with the relatively higher-valent Bismuth introducing vacancies into the lattice. These materials exhibited conductivities of 1×10 -3 ohm -1 cm -1 and an ionic transference number of 0.96 at 800° C. in an H 2 /air cell.
Another way to stabilize the hexagonal form of framework L is to use a template around which L can crystallize. The simplest template for this use may be an oxide ion. As such, a pellet of L containing 5% excess L-metal was made. The conductivity and ionic transference data of this pellet was measured in a humidified, oxygen-gradient cell, and is depicted in Table 5.
TABLE 5______________________________________Conductivity and Ionic Transference Data for 5%-excess L-metal.sup.1 in Framework LTemperature Conductivity Transference°C. ohm.sup.-1 cm.sup.-1 Number______________________________________510 7.33 × 10.sup.-6 0.17609 1.68 × 10.sup.-5 0.57713 4.12 × 10.sup.-5 0.58814 8.39 × 10.sup.-5 0.72______________________________________ .sup.1 This material was found to be monoclinic by xray diffraction analysis.
In summary, the invented ionic conductors described in the foregoing detailed description can be used as electrolytes in solid oxide fuel cells, sensors or batteries at temperatures ranging from 600° C. to 800° C. For example, the exemplary molecular framework structure compounds represented by substituted aluminum phosphates can be used as proton or oxide ion conductors. Substituted aluminum phosphates can also be used as sodium or lithium conductors in batteries. Such substituted aluminum phosphates include the material commonly known as NASICON, which has the following general formula:
A.sub.1+x D.sub.2-x/3 Si.sub.x P.sub.3-x O.sub.12-2x/3
wherein A is an alkali metal, and D is a quadrivalent ion of group IV of the periodic table. A more complete description of NASICON can be found in U.S. Pat. No. 4,465,744, which is incorporated herein by reference.
While the invention has been described with reference to details of the illustrated embodiments, these details are not intended to limit the scope of the invention as defined in the appended claims. | An electrolyte that operates at temperatures ranging from 600° C. to 800° C. is provided. The electrolyte conducts charge ionically as well as electronically. The ionic conductors include molecular framework structures having planes or channels large enough to transport oxides or hydrated protons and having net-positive or net-negative charges. Representative molecular framework structures include substituted aluminum phosphates, orthosilicates, silicoaluminates, cordierites, apatites, sodalites, and hollandites. | 8 |
CROSS REFERENCE TO RELATED APPLICATION
This application claims priority of German Patent Application No. 10 2006 002 812.0 dated Jan. 19, 2006, and German Patent of Addition Application No. 10 2006 058 274.8 dated Dec. 8, 2006, the entire disclosure of which are incorporated herein by reference.
BACKGROUND OF THE INVENTION
The invention relates to an apparatus on a spinning preparation machine, especially but not exclusively a flat card, roller card or similar, for monitoring and/or adjusting clearances at components.
When cleaning or carding the fibre material, for example, cotton and/or synthetic fibres, stationary cleaning or carding elements are normally placed facing a rotating roller fitted with clothing. To achieve a good cleaning and/or carding action, these elements must be arranged as close as possible to the clothing of the rotating roller. Adjustment is effected in the cold state or with the roller stationary. Owing to the heat generated in operation and owing to the roller expansion caused by centrifugal force during rotation, the clearance between the roller and the cleaning or carding elements diminishes. In the process, if the adjustment was not effected according to specifications, it may happen that these elements touch the roller during operation. This contact often leads to further heating and to an associated contact pressure on the clothing, with the result that this may “burst”. This is associated with considerable consequential damage.
In consequence of misadjustments or incorrect machine operation, carding machines may crash. The repair costs for such crashes are substantial. Contact between a stationary component and, for example, a carding cylinder, has destructive consequences, because due to the setting of its abrasive teeth the roller clothing exerts a strong pulling action on components on contact therewith, and when contact is discovered, for example, by an operator, the rollers take at least five minutes to run down to a standstill. Damage escalates during this time.
The effective clearance of the tips of a clothing from a machine element facing the clothing is called the carding gap. The last-mentioned element can also have a clothing, but could instead be formed by a casing element having a guide surface. The carding gap is crucial for the carding quality. The size (width) of the carding gap is an important machine parameter, which shapes both the technology (the fibre processing) and the running performance of the machine. The carding gap is set to be as narrow as possible (it is measured in tenths of a millimeter), without running the risk of a “collision” between the work elements. To ensure a uniform processing of the fibres, the gap must be as uniform as possible over the entire working width of the machine.
The carding gap is influenced in particular by the machine settings on the one hand and by the condition of the clothing on the other hand. The most important carding gap of the revolving flat card is located in the main carding zone, i.e. between the cylinder and the revolving flat assembly. At least one clothing, which adjoins the working distance, is in motion, more often than not both clothings. In order to increase the production of the card, it is endeavoured to select the operating revolution speed or the operating speed of the moving elements to be as high as the technology of fibre processing allows. The operating state alters in dependence on the operating conditions. The change is effected in the radial direction (starting from the axis of rotation) of the cylinder.
During carding, increasingly larger amounts of fibre material per unit of time are processed, which means higher speeds of the work elements and higher installed power capacities. Increasing volumetric flow rate of fibre material (output), even with a working area that remains constant, leads to increased generation of heat due to the mechanical work. But at the same time the technological carding result (sliver uniformity, degree of cleaning, reduction in neps etc.) is continuously improved, which involves more active surfaces in carding engagement and closer settings of these active surfaces with respect to the cylinder (tambour). The proportion of synthetic fibres to be processed is steadily increasing, and in this case—compared with cotton—through contact with the active surfaces of the machine more heat is generated by friction. The work elements of high-performance cards are nowadays fully enclosed on all sides, in order to comply with high safety standards, to prevent particle emission into the spinning room environment and to minimise required maintenance of the machines. Grids or even open, material-guiding surfaces that permit air exchange, belong to the past. The conditions mentioned clearly increase the input of heat into the machine, whilst the discharge of heat by means of convection clearly decreases. The resultant greater heating of high-performance cards leads to greater thermoelastic deformations, which, owing to the non-uniform distribution of the temperature field, influence the set clearances of the active surfaces: the clearances between cylinder and card top, doffer, fixed card tops and separation points with blades decrease. In an extreme case, the space set between the active surfaces can be completely absorbed by thermal expansions, so that components moving relative to one another collide. The result is major damage to the high-performance card in question. Moreover, in particular the generation of heat in the working region of the card can lead to different thermal expansions in the case of unduly large temperature differences between the components.
To reduce or avoid the risk of collisions, in practical operation the carding gap between clothings facing one another is set to be relatively wide, i.e. a certain safety clearance exists. A large carding gap, however, leads to undesirable nep formation in the card sliver. In contrast, an optimum, especially narrow size is desirable, whereby the nep count in the card sliver is substantially reduced.
In one known arrangement, a clothed, high-speed roller is located facing at least one clothed and/or unclothed component and the clearance between the components facing one another is alterable, the components arranged with a clearance being electrically isolated with respect to one another and being connected as contact elements to an electrical power supply line, in which a measuring element for ascertaining contact is located. In DE-PS 229 595, in the case of a roller card where clearance between the card wire elements is to be monitored, in accordance with a first embodiment of the publication it is known to connect the card wire covering of each element as contact to an electrical power supply line, in which there is a signalling or alarm device. According to a second embodiment, contact rockers are present, which are connected to the electrical power supply line as contacts. It is a disadvantage that even upon a single touching (contact) merely between two facing tips the circuit is closed and the signalling or alarm device takes effect. It may also happen that an electrically conductive particle is circulating with the fibre material, which leads to a spurious shutdown through point contact touch. At the high circumferential speeds and centrifugal moments of the clothed rollers, individual protruding tooth tips or small conductive particles are in practice, however, ground off after such a signal. The known apparatus allows only the mere detection of contact.
SUMMARY OF THE INVENTION
It is an aim of the invention to produce an apparatus of the kind described initially, which avoids or mitigates the said disadvantages and which in particular in a simple manner avoids an undesirable heavy contact between the components, primarily damage to a clothing, when facing components approach one another.
The invention provides an apparatus on a spinning preparation machine, comprising a clothed roller and a machine component opposed to the clothed roller and defining therewith a clearance at which contact between the roller and opposed component is to be monitored, wherein:
said clothed roller and said machine component are electrically isolated with respect to one another at said clearance during normal operation;
said clothed roller and said machine component are connected as contact elements to an electrical circuit; and
said electrical circuit includes a measuring device for quantitatively measuring the contacts.
By means of the measures according to the invention, a quantitative determination of the contacts is carried out, whereby a signal or response is avoided if there is only one or only slight contact. In particular, there is avoided an undesirable shutdown of the machine, which in continuous operation occurs in the known apparatus mentioned above owing to sporadic contacts between the work elements caused, for example, by conductive particles in the fibre material. Since these contactings only occur sporadically, they can be filtered by evaluating the number of contacts in a contact period. It is thus possible to differentiate between these contact states, for example, by means of the machine control, and to avoid damage to the clothing.
In one preferred embodiment, the output of the device for determining the quantity of the contacts is connected via a comparator to at least one limit value setter and to a signalling and/or switching device. By means of those measures, the quantity of measured values is advantageously compared with a limit value and when the limit value is exceeded a signal and/or a switching operation is initiated. The limit value is advantageously chosen so that it is not reached when individual or slight contact occurs. Exceeding the limit value, on the other hand, initiates the signalling and/or switching operation. In this way, when facing components approach one another, an undesirably heavy contact between the components is reliably avoided.
The quantity of the contacts may be determinable directly or indirectly. In a preferred embodiment, at least the number of contacts is determinable. In that case, a counting device is advantageously present for counting the number of contacts. As well, or instead, the duration and/or intensity of the contacts may be determinable. For example, a resistance-measuring device for determining the intensity of the contacts may be present. Advantageously, the amount, especially the number, of the contacts per unit of time is determinable. The components facing one another, for example, clothings may be electrically connected to the device for quantitatively determining the contacts. In certain preferred embodiments, the device for quantitatively determining the contacts comprises a comparator. Where present, the comparator is advantageously connected to a limit value setter and/or to an electronic control and regulating device, for example, a machine control.
In a preferred embodiment, two metal clothings facing one another are electrically conductive components of the electrical circuit. In that case, a lead is advantageously connected to each electrically conductive clothing. Advantageously, an electrical signal is generated upon a contact between the roller and a facing component. The electrical signals are advantageously evaluated by a device, which may in certain advantageous embodiments be a control device for the machine. The apparatus according to the invention is advantageously connected to one or more devices selected from a signalling device, an alarm device, and a shutdown device for the card. In one preferred embodiment, the apparatus according to the invention is connected to an adjusting device for the clearance, for example, for a carding gap between the roller and an opposed component.
The opposed component with which the clothed roller forms a clearance to be monitored may be a clothed component or a non-clothed component, but is preferred to be a clothed component. It may be a stationary component, or a moving component, for example, a revolving card flat.
The invention includes arrangements in which clearances at more than one machine component can be monitored, in which the clearances can be at the same or different clothed rollers.
The invention also provides an apparatus on a spinning preparation machine, especially a flat card, roller card or similar, for monitoring and/or adjusting clearances at components, in which a clothed, high-speed roller is located facing at least one clothed and/or unclothed component and the clearance between the components facing one another is alterable, wherein the components arranged with a clearance are electrically isolated with respect to one another and are connected as contact elements to an electrical power supply line in which a measuring device for ascertaining contact is located, wherein upon contacts with the clothing of the roller electrical signals are emitted and the measuring device includes a device for determining the quantity of the contacts.
In a further advantageous embodiment of the invention, the electrical capacitance between the components facing one another is determinable and, on departure from a desired capacitance, a signal is generated for an adjustment process or a switching-off process. By means of measuring the capacitance and comparing it with a desired value, the operative state of the electrical circuit can be checked. That is particularly advantageous in that it allows self-testing to be achieved. That prevents, especially, the ceasing of detection of the contacts in the event of an undesirable interruption of the electrical circuit, which can lead to substantial damage up to complete breakdown of the machine.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic side view of a card which may have an apparatus according to the invention;
FIG. 2 is an enlarged view, partly in section, of a part of the card of FIG. 1 , showing a carding segment, a fragment of a side plate with a clearance between the carding segment clothing and the cylinder clothing, which may form part of one embodiment of the invention;
FIG. 2 a shows carding elements of the carding segment as shown in FIG. 2 in detail;
FIG. 3 is a block diagram with counting device, comparator, limit value setter and electronic control and regulating arrangement (machine control) according to one embodiment of the invention;
FIG. 4 is a graph of the dependence of the number of contactings per second on the mean distance of the cylinder clothing from the facing work elements;
FIG. 5 is a block diagram of an apparatus according to a further embodiment of the invention, including a capacitance-measuring device, a capacitance comparator and a capacitance limit value setter;
FIGS. 6 a , 6 b are partial sections through a carding machine without interruption of the electrical circuit ( FIG. 6 a ) and with interruption of the electrical circuit ( FIG. 6 b );
FIGS. 7 a , 7 b are schematic representations of the capacitors and the associated capacitances without interruption of the electrical circuit ( FIG. 7 a ) and with interruption of the electrical circuit ( FIG. 7 b );
FIG. 8 shows a bearing for the rotatable journals of the cylinder with electrical isolation;
FIGS. 9 a , 9 b show an electrical sliding-action contact in engagement with a cylinder journal ( FIG. 9 a ) and disengaged from the cylinder journal.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
Referring to FIG. 1 , a flat card for example, a flat card TC 03 (Trade Mark) made by Trützschler GmbH & Co. KG. of Monchengladbach, Germany, has feed roller 1 , feed table 2 , licker-ins 3 a , 3 b , 3 c , cylinder 4 , doffer 5 , stripping roller 6 , squeezing rollers 7 , 8 , web deflector 9 , web funnel 10 , take-off rollers 11 , 12 , revolving flat 13 with flat guide rollers 13 a , 13 b and flat bars 14 , can 15 and can coiler 16 . The directions of rotation of the rollers are shown by respective curved arrows. The letter M denotes the midpoint (axis) of the cylinder 4 . The reference numeral 4 a denotes the clothing and 4 b denotes the direction of rotation of the numeral 4 a denotes the clothing and 4 b denotes the direction of rotation of the cylinder 4 . The arrows A, B, and C denote the working direction. The curved arrows drawn in the rollers denote the directions of rotation of the rollers. In an illustrative embodiment of the invention described below, an apparatus according to the invention is provided at one or more of the stationary carding segments 20 ′ and 20 ″. Instead, or as well, other work elements and/or casing elements may be provided with an apparatus according to the invention.
In the illustrative embodiment of FIGS. 2 and 3 , contacts between the cylinder 4 and stationary carding segment 20 ′ are monitored. Referring to FIG. 2 , on each side of the card an approximately semi-circular, rigid side plate 18 is secured laterally to the machine frame (not shown); cast concentrically onto its outer side in the region of the periphery thereof there is a curved, rigid bearing element 19 , which has a convex outer surface 19 a as its support surface and an underside 19 b . The apparatus according to the invention includes at least one stationary carding device 20 ′ that at both ends has bearing surfaces that lie on the convex outer surface 19 a of the bearing element (for example, an extension bend). Carding elements 20 a , 20 b with clothing strips 20 a ′, 20 b ′ (carding clothings) are mounted on the undersurface of the stationary carding segment 20 ′. The reference number 21 denotes the tip circle of the clothings 20 a ′, 20 b ′. The cylinder 4 has on its periphery a cylinder clothing 4 a , for example, a saw tooth clothing. The reference numeral 22 denotes the tip circle of the cylinder clothing 4 a . The distance between the tip circle 21 and the tip circle 22 is denoted by the letter a, and is, for example, 0.20 mm. The clearance between the convex outer surface 19 a and the tip circle 22 is denoted by the letter b. The radius of the convex outer surface 19 a is denoted by r 1 and the radius of the tip circle 22 is denoted by r 2 . The radii r 1 and r 2 intersect at the mid-point M of the cylinder 4 . The carding segment 20 ′ shown in FIG. 2 consists of a support 23 and two carding elements 20 a , 20 b , which are arranged in succession in the direction of rotation (arrow 4 b ) of the cylinder 4 , the clothings 20 a ′, 20 b ′ of the carding elements 20 a , 20 b and the clothing 4 a of the cylinder 4 lying facing each other. The carrier body 23 consists of an aluminium hollow profiled member and has continuous hollow spaces.
As shown in FIG. 3 , the carding clothing 4 a (all-steel) and the clothing strips 20 b ′ (all-steel) face one another with a clearance a (see FIG. 2 ). The cylinder clothing 4 a is connected via an electrical lead 24 and the clothing strip 20 b ′ is connected via an electrical lead 25 to a counting device 26 . The counting device 26 is able to determine the number of contacts between the card clothing 4 a and the clothing strip 20 b ′ per unit of time. An electrical power source, for example, a battery, is present in the lead 24 . The counting device 26 is connected via an electrical lead 28 to a comparator 29 , to which furthermore a limit value setter is connected. The comparator 29 is able to compare the number of contacts determined by the counting device 26 with a number of contacts preset in the limit value setter. Finally, the output of the comparator 29 is connected to the input of an electronic control and regulating device, for example, the machine control 31 . When a limit for the number of contactings per second is exceeded (see FIG. 4 ), the card K is switched off by a shutdown device 32 . The circuit may additionally include one or both of a device for determining the duration of the contacts, and a device for determining the intensity of the contacts (for example, a resistance-measuring device).
The metal clothings 4 a and 20 b ′ act like a switch in an electric circuit. The battery 27 can produce, for example, a low voltage of 5 V.
In FIG. 4 , the number of contactings per second is plotted over the mean clearance of the cylinder clothing 4 a with respect to the work elements, for example, clothing strip 20 b ′. The reference numeral 31 denotes the normal operating range of the machine, for example, the card. The reference numerals 32 and 33 denote sporadic contacts that lie below the shutdown limit, in which case the machine is not shut down. Three curves are shown for the contact duration t=0.1 ms, t=1 ms and t=2 ms. The reference numeral 34 denotes the possible shutdown limit for t=0.1 ms and 35 denotes the possible shutdown limit for t=1 ms.
In a further exemplary embodiment shown in FIG. 5 , the carding clothing 4 a (all-steel) and the clothing strips 20 b ′ (all-steel) face one another with a clearance a. The cylinder clothing 4 a is connected via an electrical lead 24 and the clothing strip 20 b ′ is connected via an electrical lead 25 to a counting device 26 . The counting device 26 is able to determine the number of contacts between the card clothing 4 a and the clothing strip 20 b ′ per unit of time. An electrical power source, for example, a battery 27 , is present in the lead 24 . The counting device 26 is connected via an electrical lead 28 to a contact-comparator 29 , to which furthermore a limit value setter 30 is connected. The comparator 29 is able to compare the number of contacts determined by the counting device 26 with a number of contacts preset in the limit value setter 30 . The output of the comparator 29 is connected to the input of an electronic control and regulating device, for example, the machine control 31 . When a limit for the number of contactings per second is exceeded, the card K is switched off by a shutdown device 32 . In those respects, the apparatus corresponds to that of FIG. 3 .
The metal clothings 4 a and 20 b ′ act like a switch in an electric circuit. The battery 27 can produce, for example, a low voltage of 5 V.
In the electrical circuit, in the example of FIG. 5 in the lead 24 , there is a device for measuring capacitance 36 , which is connected via a lead 41 to a capacitance comparator 37 to which furthermore a capacitance limit value setter 38 (desired value setter) is connected via lead 42 . The capacitance comparator 37 is able to compare the actual capacitance C 1 or C tot measured in the circuit with a preset desired capacitance C 1 . The output of the capacitance comparator 37 is connected via a lead 43 to the input of the electronic control and regulating device 31 . The existence of an interruption in the circuit is indicated by an indicating device 39 . Switching off the card K by the shutdown device 32 can also be effected.
In the embodiment of FIGS. 6 a and 6 b , the cylinder is electrically isolated, and a voltage is applied thereto. If the functional elements and the cylinder clothing 4 a should touch, this is indicated by individual countable contacts. By evaluating the contact number and duration, the machine K can be switched off in good time. Damage to the machine is therefore prevented. Given that the cylinder 4 rotates, the electrical connection is produced via a sliding-action contact (carbon rod 40 ) centrally in the cylinder journal 44 a . To safeguard the function of the system (TCM), this electrical connection is tested at regular intervals or continuously (self testing).
In the case of the cylinder 4 , the area delimited by cylinder 4 and functional elements (clothing 20 a ′, 20 b ′) is very large, whereas the clearance a is very small. Accordingly, the capacitance C 1 has to assume a very large value ( FIG. 6 a ). If contacting is interrupted in a region ( FIG. 6 b ), a second plate capacitor is produced at the point of rupture. Considered in electrical terms, a series connection of capacitors is thus produced. In this case, the total capacitance (measured variable) is calculated from the following formula:
1
C
tot
=
1
C
1
+
1
C
2
C tot —total capacitance (measured variable)
C 1 —partial capacitance 1 e.g. between cylinder and functional elements
C 2 —partial capacitance 2 at the disturbance point.
The following numerical example serves for further explanation:
In normal operation, i.e. with no interruption of the circuit ( FIG. 6 a ), the capacitance between the cylinder 4 and the functional elements equals 1000 owing to the large area. In the event of a fault, i.e. when the circuit is interrupted ( FIG. 6 b ), a further capacitance C 2 is added in the region of the interrupted electrical connection. This has a very much smaller area, here assumed at a value of 10. If these two values are inserted in the formula for the series connection, then the following is true for the total capacitance:
1
C
tot
=
1
C
10
+
1
C
1000
=
0.101
C
tot
=
1
0.101
=
9.9
If the value of the intact system ( FIG. 6 a ) of 1000 is compared with that of the defective system ( FIG. 6 b ) of 9.9, a clear difference is revealed. Such a difference signifies a malfunction in the system (self testing).
The capacitor K 1 illustrated in FIG. 7 a is determined by the area of the clothings 4 a and 20 b ′ (see FIG. 5 ), the clearance a thereof and the dielectric constant e. The capacitor K 1 (of the capacitance C 1 ) is connected to an electrical power source (symbols “+” and “−”); the electric circuit is not interrupted. According to FIG. 7 b , added to the capacitor K 1 is a second capacitor K 2 (of a capacitance C 2 ), which is determined by the end face areas of the carbon rod 40 and the journal 44 a , by the distance of the carbon rod 40 from the journal 44 (see FIG. 6 b ) and the dielectric constant ∈. A series connection of capacitors K 1 and K 2 is thus formed.
For rotatable mounting of the shaft journals 44 a and 44 b , a respective pivot bearing 45 a , 45 b is present (see FIGS. 6 a , 6 b ). In an exemplary arrangement shown in FIG. 8 , the pivot bearing 45 a is mounted in a non-rotatable part 45 2 (pot). The part 45 1 (insulating element), which engages on the one hand with the stationary side plate that is, the machine frame, and on the other hand with the part 45 2 , is electrically non-conducting, i.e. an insulator. The part 45 2 , which engages with each of the conductive bearings 45 a and 45 b , is of metal (steel), i.e. is electrically conductive. In this way, the components arranged with clearance are electrically isolated with respect to one another and are connected as contact element to the electrical power source 27 .
In a further embodiment shown in FIG. 9 a , one end face of the carbon rod 40 lies at an end face of the rotatable shaft journal 44 a , whilst the other end face of the carbon pin 40 is loaded by a compression spring 47 . The carbon rod 40 is mounted in a hollow-cylindrical holding element 46 so as to move in the axial direction. The reference numeral 48 denotes an electrical lead between the carbon rod 40 and the device for measuring capacitance 36 , which is connected via a line 49 to the metal side plate 45 a , in the manner shown in FIG. 6 b . The carbon rod 40 is in electrical contact with the shaft journal 44 a , so that the circuit is closed. If, for example, owing to wear, the carbon rod 40 has a clearance b from the shaft journal 44 a , the circuit is interrupted, as shown in FIG. 9 b . At the same time, in addition to the capacitor K 1 , the further capacitor K 2 is thereby formed (see FIG. 7 b ).
The invention has been explained using the example of a stationary component (stationary carding segment 20 ′) on a flat card. The invention also includes other components on a flat card, including non-stationary components, for example, flat bars 14 (revolving flat) and stationary and non-stationary components on other spinning preparation machines, for example stationary carding segments or rotating rollers (worker rollers, clearer rollers) on a roller card or the like.
Although the foregoing invention has been described in detail by way of illustration and example for purposes of understanding, it will be obvious that changes and modifications may be practised within the scope of the appended claims. | An apparatus on a spinning preparation machine for monitoring and/or adjusting clearances at components has a clothed, high-speed roller located facing at least one clothed and/or unclothed component and the clearance between the components facing one another is alterable. The roller and opposed component(s) are electrically isolated with respect to one another and are connected as contact elements to an electrical power supply line in which a measuring device for ascertaining contact is located. In order to avoid an undesirably heavy contact between the components, electric signals are emitted upon contacts with the clothing of the roller and the measuring device is arranged quantitatively to determine the contacts. | 3 |
RELATED APPLICATIONS
[0001] The present application is a continuation under 35 U.S.C § 120 of U.S. patent application Ser. No. 13/488,345, filed Jun. 4, 2012, which is a continuation of U.S. patent application Ser. No. 11/658,702, filed Oct. 8, 2007, now U.S. Pat. No. 8,193,196. issued on Jun. 5, 2012, which in turn is filed under 35 U.S.C. §371 as the U.S. national application of International Patent Application No. PCT/EP2006/001755, filed Feb. 27, 2006, which in turn claims priority to the European Patent Application No. EP 05004695.2, filed Mar. 3, 2005, the entire disclosure of all of which is hereby incorporated by reference herein, including the drawings.
BACKGROUND OF THE INVENTION
[0002] The rifaximin (INN; see The Merck Index, XIII Ed., 8304) is an antibiotic pertaining to the rifamycin class, exactly it is a pyrido-imidazo rifamycin described and claimed in the Italian Patent IT 1154655, while the European Patent EP 0161534 describes and claims a process for its production starting from the rifamycin O (The Merck Index, XIII Ed., 8301).
[0003] Both these patents describe the purification of the rifaximin in a generic way saying that the crystallization can be carried out in suitable solvents or solvent systems and summarily showing in some examples that the product coming from the reaction can be crystallized from the 7:3 mixture of ethyl alcohol/water and can be dried both under atmospheric pressure and under vacuum without saying in any way neither the experimental conditions of crystallization and drying, nor any distinctive crystallographic characteristic of the obtained product.
[0004] The presence of different polymorphs had not been just noticed and therefore the experimental conditions described in both patents had been developed with the goal to get a homogeneous product having a suitable purity from the chemical point of view, apart from the crystallographic aspects of the product itself.
[0005] It has now be found, unexpectedly, that some polymorphous forms exist whose formation, in addition to the solvent, depends on the conditions of time and temperature at which both the crystallization and the drying are carried out.
[0006] These orderly polymorphous forms will be, later on, conventionally identified as rifaximin δ ( FIG. 1 ) and rifaximin ε ( FIG. 2 ) on the basis of their respective specific diffractograms reported in the present application.
[0007] The polymorphous forms of the rifaximin have been characterized through the technique of the powder X-ray diffraction.
[0008] The identification and characterization of these polymorphous forms and, contemporarily, the definition of the experimental conditions for obtaining them is very important for a compound endowed with pharmacological activity which, like the rifaximin, is marketed as medicinal preparation, both for human and veterinary use. In fact it is known that the polymorphism of a compound that can be used as active principle contained in a medicinal preparation can influence the pharmaco-toxicologic properties of the drug. Different polymorphous forms of an active principle administered as drug under oral or topical form can modify many properties thereof like bioavailability, solubility, stability, color, compressibility, flowability and workability with consequent modification of the profiles of toxicological safety, clinical effectiveness and productive efficiency.
[0009] What above mentioned is confirmed with authority by the fact that the authorities that regulate the grant of the authorization for the admission of the drugs on the market require that the manufacturing methods of the active principles are standardized and controlled in such a way that they give homogeneous and sound results in terms of polymorphism of the production batches (CPMP/QWP/96, 2003—Note for Guidance on Chemistry of new Active Substance; CPMP/ICH/367/96—Note for guidance specifications: test procedures and acceptance criteria for new drug substances and new drug products: chemical substances; Date for coming into operation: May 2000).
[0010] The need of the above-mentioned standardization has further been strengthened just in the field of the rifamycin antibiotics from Henwood S. Q., de Villiers M. M., Liebenberg W. and Lotter A. P., Drug Development and Industrial Pharmacy, 26 (4), 403-408, (2000), who have ascertained that different production batches of the rifampicin (INN) made from different manufacturers differ among them because they show different polymorphous characteristics, and as a consequence they show different profiles of dissolution together with consequent alteration of the respective pharmacological properties.
[0011] By applying the processes of crystallization and drying generically disclosed in the previous patents IT 1154655 and EP 0161534 it has been found that under some experimental conditions the poorly crystalline form of the rifaximin is obtained while under other experimental conditions the other crystalline polymorphous forms of the rifaximin are obtained. Moreover it has been found that some parameters, absolutely not disclosed in the above-mentioned patents, like for instance the conditions of preservation and the relative humidity of the ambient, have the surprising effect to determine the form of the polymorph.
[0012] The polymorphous forms of the rifaximin object of the present patent application were never seen or hypothesized, while thinking that a sole homogeneous product would always have been obtained whichever method would have been chosen within the range of the described conditions, irrespective of the conditions used for crystallizing, drying and preserving.
[0013] It has now been found that the formation of the δ and ε forms depends on the presence of water within the crystallization solvent, on the temperature at which the product is crystallized and on the amount of water present into the product at the end of the drying phase.
[0014] The form δ and the form ε of the rifaximin have then been synthesized and they are the object of the invention.
[0015] In particular the form δ is characterized by the residual content of water in the dried solid material in the range from 2.5% and 6% (w/w), more preferably from 3% and 4.5%, while the form ε is the result of a polymorphic transition under controlled temperature moving from the form δ.
[0016] These results have a remarkable importance as they determine the conditions of industrial manufacturing of some steps of working which could not be considered critical for the determination of the polymorphism of a product, like for instance the maintaining to a crystallized product a quantity of water in a stringent range of values, or the process of drying the final product, in which a form, namely form δ, has to be obtained prior to continuing the drying to obtain the form δ, or the conditions of preservation of the end product, or the characteristics of the container in which the product is preserved.
[0017] Rifaximin exerts its broad antibacterial activity in the gastrointestinal tract against localized gastrointestinal bacteria that cause infectious diarrhea including anaerobic strains. It has been reported that rifaximin is characterized by a negligible systemic absorption, due to its chemical and physical characteristics (Descombe J. J. et al. Pharmacokinetic study of rifaximin after oral administration in healthy volunteers. Int J Clin. Pharmacol. Res., 14 (2), 51-56, (1994))
[0018] Now we have found that it is possible on the basis of the two identified polymorphic forms of rifaximin to modulate its level of systemic adsorption, and this is part of the present invention, by administering distinct polymorphous forms of rifaximin, namely rifaximin δ and rifaximin ε. It is possible to have a difference in the adsorption of almost 100 folds in the range from 0.001 to 0.3 μg/ml in blood.
[0019] The evidenced difference in the bioavailability is important because it can differentiate the pharmacological and toxicological behavior of the two polymorphous of rifaximins δ and ε.
[0020] As a matter of fact, rifaximin ε is negligibly absorbed through the oral route while rifaximin δ shows a mild absorption.
[0021] Rifaximin ε is practically not absorbed, might act only through a topical action, including the case of the gastro-intestinal tract, with the advantage of very low toxicity.
[0022] On the other way, rifaximin δ, which is mildly absorbed, can find an advantageous use against systemic microorganisms, able to hide themselves and to partially elude the action of the topic antibiotics.
[0023] In respect of possible adverse events coupled to the therapeutic use of rifaximin of particular relevance is the induction of bacterial resistance to the antibiotics. Generally speaking, it is always possible in the therapeutic practice with antibiotics to induce bacterial resistance to the same or to other antibiotic through selection of resistant strains.
[0024] In case of rifaximin, this aspect is particularly relevant, since rifaximin belongs to the rifamycin family, a member of which, the rifampicin, is largely used in tuberculosis therapy. The current short course treatment of tuberculosis is a combination therapy involving four active pharmaceutical ingredients: rifampicin, isoniazid, ethambutol and pyrazinamide and among them rifampicin plays a pivotal role. Therefore, any drug which jeopardized the efficacy of the therapy by selecting for resistance to rifampicin would be harmful. (Kremer L. et al. “Re-emergence of tuberculosis: strategies and treatment”, Expert Opin. Investig. Drugs, 11 (2), 153-157, (2002)).
[0025] In principle, looking at the structural similarity between rifaximin and rifampicin, it might be possible by using rifaximin to select resistant strains of M. tuberculosis and to induce cross-resistance to rifampicin. In order to avoid this negative event it is crucial to have a control of quantity of rifaximin systemically absorbed.
[0026] Under this point of view, the difference found in the systemic absorption of the δ and ε forms of the rifaximin is significant, since also at sub-inhibitory concentration of rifaximin, such as in the range of from 0.1 to 1 μg/ml, selection of resistant mutants has been demonstrated to be possible (Marchese A. et al. In vitro activity of rifaximin, metronidazole and vancomycin against clostridium difficile and the rate of selection of spontaneously resistant mutants against representative anaerobic and aerobic bacteria, including ammonia-producing species. Chemotherapy, 46(4), 253-266, (2000)).
[0027] According to what above said, the importance of the present invention, which has led to the knowledge of the existence of the above mentioned rifaximin polymorphous forms and to various industrial routes for manufacturing pure single forms having different pharmacological properties, is clearly strengthened.
[0028] The above-mentioned δ and ε forms can be advantageously used as pure and homogeneous products in the manufacture of medicinal preparations containing rifaximin.
[0029] As already said, the process for manufacturing rifaximin from rifamycin O disclosed and claimed in EP 0161534 is deficient from the point of view of the purification and identification of the product obtained; it shows some limits also from the synthetic point of view as regards, for instance, the very long reaction times, from 16 to 72 hours, very little suitable for an industrial use and moreover because it does not provide for the in situ reduction of the rifaximin oxidized that may be formed within the reaction mixture.
[0030] Therefore, a further object of the present invention is an improved process for the industrial manufacturing of the δ and ε forms of the rifaximin, herein claimed as products and usable as defined and homogeneous active principles in the manufacture of the medicinal preparations containing such active principle.
BRIEF DESCRIPTION OF THE DRAWINGS
[0031] FIG. 1 is a powder X-ray diffractogram of rifaximin δ.
[0032] FIG. 2 is a powder X-ray diffractogram of rifaximin ε.
DESCRIPTION OF THE INVENTION
[0033] As already said, the form δ and the form ε of the antibiotic known as rifaximin (INN), processes for their production and the use thereof in the manufacture of medicinal preparations for oral or topical route, are object of the present invention.
[0034] A process object of the present invention comprises reacting one molar equivalent of rifamycin O with an excess of 2-amino-4-methylpyridine, preferably from 2.0 to 3.5 molar equivalents, in a solvent mixture made of water and ethyl alcohol in volumetric ratios between 1:1 and 2:1, for a period of time between 2 and 8 hours at a temperature between 40° C. and 60° C.
[0035] At the end of the reaction the reaction mass is cooled to room temperature and is added with a solution of ascorbic acid in a mixture of water, ethyl alcohol and aqueous concentrated hydrochloric acid, under strong stirring, in order to reduce the small amount of oxidized rifaximin that forms during the reaction and finally the pH is brought to about 2.0 by means of a further addition of concentrated aqueous solution of hydrochloric acid, in order to better remove the excess of 2-amino-4-methylpyridine used in the reaction. The suspension is filtered and the obtained solid is washed with the same solvent mixture water/ethyl alcohol used in the reaction. Such semi finished product is called “raw rifaximin”.
[0036] The raw rifaximin can be directly submitted to the subsequent step of purification. Alternately, in case long times of preservation of the semi finished product are expected, the raw rifaximin can be dried under vacuum at a temperature lower than 65° C. for a period of time between 6 and 24 hours, such semi finished product is called “dried raw rifaximin”.
[0037] The so obtained raw rifaximin and/or dried raw rifaximin are purified by dissolving them in ethyl alcohol at a temperature between 45° C. and 65° C. and by crystallizing them by addition of water, preferably in weight amounts between 15% and 70% in respect of the amount by weight of the ethyl alcohol used for the dissolution, and by keeping the obtained suspension at a temperature between 50° C. and 0° C. under stifling during a period of time between 4 and 36 hours.
[0038] The suspension is filtered and the obtained solid is washed with water and dried under vacuum or under normal pressure, with or without a drying agent, at a temperature between the room temperature and 105° C. for a period of time between 2 and 72 hours.
[0039] The achievement of the δ and ε forms depends on the conditions chosen for the crystallization. In particular, the composition of the solvent mixture from which the crystallization is carried out, the temperature at which the reaction mixture is kept after the crystallization and the period of time at which that temperature is kept, have proven to be critical.
[0040] More precisely, the δ and ε rifaximins are obtained when the temperature is first brought to a value between 28° C. and 32° C. in order to cause the beginning of the crystallization, then the suspension is brought to a temperature between 40° C. and 50° C. and kept at this value for a period of time between 6 and 24 hours, then the suspension is quickly cooled to 0° C., in a period of time between 15 minutes and one hour, is filtered, the solid is washed with water and then is dried.
[0041] The step of drying has an important part in obtaining the δ and ε polymorphous forms of the rifaximin and has to be checked by means of a suitable method fit for the water dosage, like for instance the Karl Fisher method, in order to check the amount of remaining water present in the product under drying.
[0042] The obtaining of the rifaximin δ during the drying in fact depends on the end remaining amount of water which should be comprised from 2.5% (w/w) and 6% (w/w), more preferably between—3% and 4.5%, and not from the experimental conditions of pressure and temperature at which this critical limit of water percent is achieved.
[0043] In order to obtain the poorly adsorbed ε form it has to start from the δ form and it has to be continued the drying under vacuum or at atmospheric pressure, at room temperature or at high temperatures, in the presence or in the absence of drying agents, provided that the drying is prolonged for the time necessary so that the conversion in form E is achieved.
[0044] Both the forms δ and ε of the rifaximin are hygroscopic, they absorb water in a reversible way during the time in the presence of suitable conditions of pressure and humidity in the ambient and are susceptible of transformation to other forms.
[0045] The transitions from one form to another result to be very important in the ambit of the invention, because they can be an alternative manufacturing method for obtaining the form desired for the production of the medicinal preparations. Therefore, the process that allows to turn the rifaximin δ into rifaximin ε in a valid industrial manner is important part of the invention.
[0046] The process concerning the transformation of the rifaximin δ into rifaximin ε comprises drying the rifaximin δ under vacuum or at atmospheric pressure, at room temperature or at high temperatures, in the presence or in the absence of drying agents, and keeping it for a period of time until the conversion is obtained, usually between 6 and 36 hours.
[0047] From what above said, it results that during the phase of preservation of the product a particular care has to be taken so that the ambient conditions do not change the water content of the product, by preserving the product in ambient having controlled humidity or in closed containers that do not allow in a significant way the exchange of water with the exterior ambient.
[0048] The polymorph called rifaximin δ is characterized from a content of water in the range between 2.5% and 6%, preferably between 3.0% and 4.5% and from a powder X-ray diffractogram (reported in FIG. 1 ) which shows peaks at the values of the diffraction angles 2θ of 5.70°±0.2, 6.7°±0.2, 7.1°±0.2, 8.0°±0.2, 8.7°±0.2, 10.4°±0.2, 10.8°±0.2, 11.3°±0.2, 12.1°±0.2, 17.0°±0.2, 17.3°±0.2, 17.5°±0.2, 18.5°±0.2, 18.8°±0.2, 19.1°±0.2, 21.0°±0.2, 21.5°±0.2. The polymorph called rifaximin E is characterized from a powder X-ray diffractogram (reported in FIG. 2 ) which shows peaks at the values of the diffraction angles 2θ of 7.0°±0.2, 7.3 °±0.2, 8.2°±0.2, 8.7°±0.2, 10.3°±0.2, 11.1°±0.2, 11.7°±0.2, 12.4°±0.2, 14.5°±0.2, 16.3°±0.2, 17.2°±0.2, 18.0°±0.2, 19.4°±0.2.
[0049] The diffractograms have been carried out by means of the Philips X′Pert instrument endowed with Bragg-Brentano geometry and under the following working conditions:
[0050] X-ray tube: Copper
[0051] Radiation used: K (α1), K (α2)
[0052] Tension and current of the generator: KV 40, mA 40
[0053] Monochromator: Graphite
[0054] Step size: 0.02
[0055] Time per step: 1.25 seconds
[0056] Starting and final angular 2θ value: 3.0°/30.0°
[0057] The evaluation of the content of water present in the analysed samples has always been carried out by means of the Karl Fisher method.
[0058] Rifaximin δ and rifaximin ε differ each from other also because they show significant differences as regards bioavailability.
[0059] A bioavailability study of the two polymorphs has been carried out on Beagle female dogs, treated them by oral route with a dose of 100 mg/kg in capsule of one of the polymorphs, collecting blood samples from the jugular vein of each animal before each dosing and 1, 2, 4, 6, 8 and 24 hours after each dosing, transferring the samples into tubes containing heparin and separating the plasma by centrifugation.
[0060] The plasma has been assayed for rifaximin on the validated LC-MS/MS method and the maximum observed plasma concentration (Cmax), the time to reach the Cmax (Tmax), and the area under the concentration-time curve (AUC) have been calculated.
[0061] The experimental data reported in the following table 1 clearly show that rifaximin ε is negligibly absorbed, while rifaximin δ is absorbed at a value (Cmax=0.308 μg/ml) comprised in the range of from 0.1 to 1.0 μg/ml.
[0000]
TABLE 1
Pharmacokinetic parameters for rifaximin polymorphs following single
oral administration of 100 mg/kg by capsules to female dogs
Cmax ng/ml
Tmax h
AUC0-24 ng · h/ml
Mean
Mean
Mean
Polymorph δ
308.31
2
801
Polymorph ε
6.86
4
42
[0062] The above experimental results further point out the differences existing among the two rifaximin polymorphs.
[0063] The forms δ and ε can be advantageously used in the production of medicinal preparations having antibiotic activity, containing rifaximin, for both oral and topical use. The medicinal preparations for oral use contain the rifaximin δ and ε together with the usual excipients as diluting agents like mannitol, lactose and sorbitol; binding agents like starches, gelatins, sugars, cellulose derivatives, natural gums and polyvinylpyrrolidone; lubricating agents like talc, stearates, hydrogenated vegetable oils, polyethylenglycol and colloidal silicon dioxide; disintegrating agents like starches, celluloses, alginates, gums and reticulated polymers; coloring, flavoring and sweetening agents.
[0064] All the solid preparations administrable by oral route can be used in the ambit of the present invention, for instance coated and uncoated tablets, capsules made of soft and hard gelatin, sugar-coated pills, lozenges, wafer sheets, pellets and powders in sealed packets.
[0065] The medicinal preparations for topical use contain the rifaximin δ and ε together with the usual excipients like white petrolatum, white wax, lanoline and derivatives thereof, stearylic alcohol, propylenglycol, sodium lauryl sulfate, ethers of the fatty polyoxyethylene alcohols, esters of the fatty polyoxyethylene acids, sorbitan monostearate, glyceryl monostearate, propylene glycol monostearate, polyethylene glycols, methylcellulose, hydroxymethylpropylcellulose, sodium carboxymethylcellulose, colloidal aluminum and magnesium silicate, sodium alginate.
[0066] All the topical preparations can be used in the ambit of the present invention, for instance the ointments, the pomades, the creams, the gels and the lotions.
[0067] The invention is herein below illustrated from some examples that do not have to be taken as a limitation of the invention: from what described results in fact evident that the forms δ and ε can be obtained by suitably combining between them the above mentioned conditions of crystallization and drying.
Example 1
Preparation of Raw Rifaximin and of Dried Raw Rifaximin
[0068] In a three-necked flask equipped with mechanic stirrer, thermometer and reflux condenser, 120 ml of demineralized water, 96 ml of ethyl alcohol, 63.5 g of rifamycin O and 27.2 g of 2-amino-4-methylpyridine are loaded in succession at room temperature. After the loading, the mass is heated at 47±3° C., is kept under stirring at this temperature for 5 hours, then is cooled to 20±3° C. and, during 30 minutes, is added with a mixture, prepared separately, made of 9 ml of demineralized water, 12.6 ml of ethyl alcohol, 1.68 g of ascorbic acid and 9.28 g of aqueous concentrated hydrochloric acid. At the end of the addition, the mass is kept under stirring for 30 minutes at an interior temperature of 20±3° C. and then, at the same temperature, 7.72 g of concentrated hydrochloric acid are dripped until a pH equal to 2.0.
[0069] At the end of the addition, the mass is kept under stifling, always at an interior temperature equal to 20° C., for 30 minutes, then the precipitate is filtered and washed by means of a mixture made of 32 ml of demineralized water and of 25 ml of ethyl alcohol. The so obtained “raw rifaximin” (89.2 g) is dried under vacuum at room temperature for 12 hours obtaining 64.4 g of “dried raw rifaximin” which shows a water content equal to 5.6%. The product by further drying under vacuum until the weight of 62.2 g of dried raw rifaximin having a water content equal to 3.3%, whose diffractogram corresponds to the polymorphous form δ characterized from a powder X-ray diffractogram showing peaks at values of angles 2θ of 5.7°±0.2, 6.7°±0.2, 7.1°±0.2, 8.0°±0.2, 8.7°±0.2, 10.4°±0.2, 10.8°±0.2, 11.3°±0.2, 12.1°±0.2, 17.0°±0.2, 17.3°±0.2, 17.5°±0.2, 18.5°±0.2, 18.8°±0.2, 19.1°±0.2, 21.0°±0.2, 21.5°±0.2. The product is hygroscopic.
Example 2
Preparation of Rifaximin ε
[0070] Example 1 is repeated and after having obtained the δ form, the solid powder is further dried under vacuum for 24 hours at the temperature of 65° C. The product obtained is rifaximin s characterized from a powder X-ray diffractogram showing peaks at values of angles 2θ of 7.0°±0.2, 7.3°±0.2, 8.2°±0.2, 8.7°±0.2, 10.3°±0.2, 11.1°±0.2, 11.7°±0.2, 12.4°±0.2, 14.5°±0.2, 16.3°±0.2, 17.2°±0.2, 18.0°±0.2, 19.4°±0.2.
Example 3
Bioavailability in Dogs by Oral Route
[0071] Eight pure-bred Beagle females dogs having 20 weeks of age and weighing between 5.0 and 7.5 kg have been divided into two groups of four.
[0072] The first of these group has been treated with rifaximin δ, the second with rifaximin ε according to the following procedure.
[0073] To each dog have been administered by the oral route 100 mg/kg of one of the rifaximin polymorphs into gelatin capsules and blood samples of 2 ml each have been collected from the jugular vein of each animal before each dispensing and 1, 2, 4, 6, 8 and 24 hours after the administration.
[0074] Each sample has been transferred into a tube containing heparin as anticoagulant and has been centrifuged; the plasma has been divided into two aliquots, each of 500 μl and has been frozen at −20° C.
[0075] The rifaximin contained in the plasma has been assayed by means of the validated LC-MS/MS method and the following parameters have been calculated according to standard non-compartmental analysis:
[0076] Cmax=maximum observed plasma concentration of rifaximin in the plasma;
[0077] Tmax=time at which the Cmax is reached;
[0078] AUC=area under the concentration-time curve calculated through the linear trapezoidal rule.
[0079] The results reported in the table 1 clearly show how the rifaximin 8 is much more absorbed, more than 40 times, in respect of rifaximin E, which is practically not absorbed. | Crystalline polymorphous forms of the rifaximin (INN) antibiotic named rifaximin δ and rifaximin ε useful in the production of medicinal preparations containing rifaximin for oral and topical use and obtained by means of a crystallization process carried out by hot-dissolving the raw rifaximin in ethyl alcohol and by causing the crystallization of the product by addition of water at a determinate temperature and for a determinate period of time, followed by a drying carried out under controlled conditions until reaching a settled water content in the end product, are the object of the invention. | 2 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a tool for cutting, drilling, grinding, or polishing metallic or non-metallic materials. More specifically, this invention relates to a rotary tool which is suitable for cutting, drilling, grinding, or polishing metals such as iron, aluminum, and copper, or alloys of such metals, or non-metallic materials such as stone, monocrystalline or polycrystalline silicons, and ceramics.
2. Description of the Related Art
Plastics which are reinforced with inorganic long fibers are well known as "FRP". For example, in "Kogyo Zairyo (Industrial Material)", Vol. 37, No. 1, (published in 1989 by Nikkan Kogyo Shinbunsha) there is disclosed a FRP consisting of an alumina fiber reinforced epoxy resin. Such FRPs have been utilized in the field of structural members.
Examples of well-known conventional rotary tools include the carborundum grindstone and the alumina grindstone. The carborundum grindstone, for example, consists of a porous material that is manufactured by binding carborundum abrasive grains together by means of a binder. Because of its porous structure, however, it cannot contain a sufficient amount of abrasive grains, resulting in a rather poor working efficiency. In addition, its pores will become clogged with chips, so that it is subject to early deterioration in cutting quality.
Japanese Patent Examined Publication No. 54-4800 and Japanese Patent Unexamined Publication No. 59-97845 disclose a buffing material and a grindstone, which consist of porous materials made of glass fibers. However, glass fibers exhibit a low degree of hardness, so that their field of application is limited. Moreover, they are all porous, which means they are rather poor in working efficiency and subject to clogging.
Japanese Patent Application No. 63-47374 discloses a lapping material containing inorganic fibers. This lapping material, however, cannot be applied to a rotary tool; that is for a tool which is to be held at a certain angle with respect to the surface to be lapped.
SUMMARY OF THE INVENTION
It is accordingly an object of this invention to provide a novel rotary tool which can perform cutting, drilling, grinding, and polishing operations with a higher efficiency than conventional grindstones and which is free from clogging during its operation. That is, with a rotary tool in accordance with this invention, an excellent working efficiency can be secured by use of a plastic material which contains a large amount of a hard substance corresponding to the abrasive grains of a grindstone for cutting workpieces and, at the same time, since no clogging occurs, an excellent cutting quality can be maintained for a long time.
In accordance with this invention, there is provided a rotary tool made of a compact (not porous) material which contains 50 to 81 volume % of inorganic long fibers selected from the following group: alumina fibers, boron fibers, silicon carbide fibers, and silicon nitride fibers, the remaining portion of the compact material consisting of a thermosetting resin matrix.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1A and 1B show examples of the rotary tool in accordance with an embodiment of this invention;
FIGS. 2A and 2B respectively show a conventional grindstone and an example of the rotary tool in accordance with another embodiment of this invention;
FIGS. 3A to 3F show examples of the rotary tool in accordance with, still another embodiment of this invention; and
FIG. 4 shows an example of the rotary tool in accordance with still another embodiment of this invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
This invention employs inorganic long fibers with a high degree of hardness instead of conventional abrasive grains constituting grindstones. Alumina fibers, boron fibers, silicon carbide fibers, and silicon nitride fibers provide an excellent cutting quality since they have a sufficiently high degree of hardness.
The inorganic long fibers employed in this invention may have a small diameter, which is in the range, for example, of 3 μm to 30 μm.
The rotary tool of this invention is made of a material containing 50 to 81 volume % of such inorganic long fibers, which are bound compact together by means of a binder so that the material would have no pores.
As stated above, conventional grindstones are porous and have a lot of pores, their abrasive grain content being 50 volume % or less. In contrast, the material or the rotary tool in accordance with this invention contains 50 volume % or more of inorganic long fibers such as Al 2 O 3 -type fibers, which constitute the cutting elements. Accordingly, the cutting edge for cutting workpieces exhibits a high density, so that a higher working efficiency can be attained than with a conventional grindstone, along with less wear of the tool being involved. Since it has a compact structure without any pores, the tool material of this invention does not become clogged with chips, whereas the pores of conventional grindstones are liable to be filled with chips, which would cause damage to the surface of the workpiece. With the rotary tool of this invention, the thermosetting resin constituting the matrix is worn somewhat earlier than the inorganic long fibers, so that the rotary tool exhibits a brush-like working surface, with inorganic long fibers slightly protruding from the matrix surface. These inorganic fibers protruding in a brush-like manner serve as the cutting elements, providing a high cutting efficiency. The chips remaining on the workpiece are removed by the brush-like inorganic long fibers of the working surface as the rotary tool rotates.
The inventors have found out that the rotary tool of this invention, which is made of a material containing 50 volume % of inorganic long fibers, can be used without particularly taking into consideration the angle of application with respect to the workpiece since it can provide an excellent cutting quality in all directions. In accordance with this invention, the protruding inorganic long fibers constitute the cutting edge, which means, by employing inorganic long fibers with a small diameter, the cut end surface, polished surface, and the like of the workpiece can be made smooth and fine. Generally, the greater the inorganic long fiber amount is, the better. An inorganic long fiber content of more than 81 volume %, however, will exceed the upper limit of the density in which the fibers can be packed, resulting in a defective impregnation of the thermosetting resin. The thermosetting resin to be employed in this invention may be: an epoxy resin, an unsaturated polyester resin, a vinyl ester resin, a bismaleimide resin, a phenol resin, and the like. Of these resins, an epoxy resin would be most suitable for manufacturing a rotary tool since it can firmly adhere to the inorganic long fibers without generating any pores.
The inorganic fiber reinforced plastic of this invention can be manufactured as follows: first, a thermosetting resin such as an epoxy resin is placed, for example, on a film in a certain thickness. Then, 50 to 81 volume % of inorganic fibers that are cut in an appropriate length are evenly dispersed on it, with the fibers being oriented in a variety of ways. Afterwords, thermosetting resin is placed on these fibers, thus sandwiching the inorganic long fibers between layers of thermosetting resin. By pressing the whole thing from both above and below with rollers or the like, the layer of inorganic long fibers is impregnated with the thermosetting resin without generating any pores. The sheet of material thus obtained is left to stand at a certain temperature for several days so as to put it in a B-stage (a half-cured condition which is suitable for pressurizing and curing through heating). Afterwards, a required number of sheets of the material thus obtained are superimposed on each other and are heated to be cured under pressure, thereby obtaining a compact plate having no pores.
A compact plate whose inorganic long fibers are oriented in the same direction and which includes no pores, can be obtained by, for example, superimposing unidirectional prepregs on each other in such a manner that the fibers are oriented in the same direction and then curing the plate thus obtained through pressurizing in an autoclave.
A compact poreless plate in which half of the inorganic long fibers are oriented in one direction and in which the remaining inorganic long fibers are oriented in the direction perpendicular this one direction, can be obtained by superimposing cloths which are woven with warps and wefts of inorganic long fibers, binding them together by means of a thermosetting resin and molding them into a compact plate under sufficient pressure.
Further, a compact plate having no pores can also be obtained in the following manner: first, prepregs are prepared by impregnating inorganic-fiber cloths with a thermosetting resin. Then, a large number of such prepregs thus obtained are superimposed on each other and are sufficiently pressed between heating plates. Apart from this, a poreless compact plate in which inorganic long fibers cross each other at right angles or are mutually inclined, can be obtained in the following manner: first, layers of inorganic long fibers are prepared which are impregnated with a thermosetting resin and in which the inorganic long fibers are oriented in the same direction, as described above. Then, these layers are put in the B-stage to obtain UD prepregs (unidirectional prepregs). A large number of such UD prepregs are superimposed on each other, with their fibers being oriented in the same direction. Afterwards, another layer is formed thereon, in which the fibers are oriented at right angles or inclined with respect to the fibers of the layers obtained by superimposing UD prepregs as described above. Then, a large number of UD prepregs are superimposed thereon in such a manner that the fibers of each layer are at right angles or inclined with respect to the adjacent layer. The layers thus superimposed together are sufficiently pressed to become a compact plate.
In accordance with still another method, a compact plate in which inorganic fibers are arranged in parallel or cross each other, can be obtained in the following manner: inorganic fibers impregnated with a thermosetting resin are wound around a cylinder in parallel with its periphery or diagonal thereto. The fiber coil thus obtained is cut open in the axial direction to obtain plate-like portions, which are cured separately through heating in an autoclave, or, instead, a large number of such plate-like portions may be laminated together. Alternatively, they may be pressed using a heating die.
The inorganic fiber reinforced plastic manufactured by one of these methods is processed using, for example, a diamond grindstone, thereby easily obtaining a rotary tool in accordance with this invention which has a desired configuration.
In accordance with this invention, a disc-like rotary tool is provided, which is adapted to rotate around its axis. Examples of such a rotary tool are shown in FIGS. 1A and 1B, of which FIG. 1A shows a rotary tool for cutting and FIG. 1B shows a rotary tool for grinding or polishing.
In accordance with this invention, a rotary tool is provided, which is composed of a rotating tip 5 and a rotation shaft 3 for rotating this rotating tip 5, the rotation shaft 3 and the rotating tip 5 being formed integrally of an inorganic fiber reinforced plastic.
FIG. 2B shows an example of such a rotary tool. In a conventional carborundum grindstone, as shown in FIG. 2A, a carborundum rotating tip 5 is fixed to a steel rotation shaft 3 by means, for example, of an adhesive agent.
The operation of thus putting these parts together is bothersome. In addition, the joint section is not strong enough in many cases. In contrast, the rotating tip 5 of the rotary tool of this invention, which is shown in FIG. 2B, is formed integrally with the associated rotation shaft 3. That is, the rotary tool of this invention is in the form of an integral body made of an inorganic fiber reinforced plastic. As shown in FIG. 2B, the inorganic fibers 4 of the rotary tool of this invention may be arranged in the axial direction of the rotation shaft 3. Such arrangement is advantageous in that the high-strength rotation shaft 3 is formed integrally with the rotating tip 5, with no joint section existing between them.
In accordance with this invention, the rotating tip of a rotary tool of the above-described type has a disc-like or a cylindrical configuration. As stated above, a rotary tool in accordance with this invention is made of an inorganic fiber reinforced plastic which contains a large amount of inorganic fibers 4. Accordingly, the outer peripheral surface of the rotating tip 5 shown in FIG. 2B also exhibits a fine cutting edge with high density suitable for cutting workpieces, so that, even though the inorganic fibers 4 are arranged, for example, in parallel with the outer peripheral surface of the cylinder, it is not necessary to particularly take into consideration the angle of application with respect to the workpiece, thus providing an excellent cutting quality in all directions.
In accordance with this invention, the rotating tip of a rotary tool may have a cylindrical, a conical, a pyramid-like, or a truncated-cone-like configuration. FIGS. 3A to 3F show examples of such rotating tips, of which FIGS. 3A and 3B show conical rotating tips; FIG. 3C shows a pyramid-like rotating tip; FIG. 3D shows a truncated-cone-like rotating tip; FIG. 3F shows a cylindrical rotary tool in which the rotating tip and the rotation shaft have the same diameter; and FIG. 3E shows a rotary tool in which the diameter of the rotating tip is different from that of the rotation shaft. The "conical" configuration in this invention includes ones with a rounded tip (FIG. 3B) as well as those with a pointed tip (FIG. 3A). Likewise, the "pyramid-like" and the "truncated-cone-like" configurations naturally include ones which are not exactly to be called as such in the geometrical sense but are only approximately so. Rotary tools having such configurations are suitable for drilling workpieces, or grinding or polishing recesses in workpieces.
In accordance with this invention, the rotating tip is formed as a column or a cylinder with a brush-like configuration. FIG. 4 shows an example of such a rotating tip. The rotating tip 5 shown has elements 6 which correspond to the bristles of a brush. Each of these elements 6 is also made of an inorganic fiber reinformed plastic which contains 50 to 81 volume % of inorganic fibers and exhibits a high-density fine cutting edge for cutting workpieces. When applied to a workpiece, its elements 6 are bent in conformity with the surface of the workpiece while the tool rotates, which means this rotary tool is suitable for grinding surfaces having complicated configurations or for grinding workpieces with a smooth finish.
Embodiments
A test was performed as follows: a workpiece, which consisted of a steel plate (S45C), was ground by moving rotary tools back and forth twenty times over a distance of 100 mm.
Each rotary tool had a disc-like configuration and had an outer diameter of 150 mm and a thickness of 1.0 mm. The grinding performed was of a dry type; each rotary tool was pressed against the workpiece with the same force and was moved back and forth at the same speed while rotating it at a speed of 3,000 r.p.m.
Rotary tool No. 1 is in accordance with this invention and is made of a compact material containing 60 volume % of alumina long fibers.
Rotary tool No. 2 is only different from rotary tool No. 1 in that it is made of a material which contains alumina long fibers having a diameter of approximately 10 μm.
Rotary tool No. 3 is a comparison example, which is made of a material containing 20 volume % of alumina long fibers with a diameter of 15 μm.
Rotary tool No. 4 is a comparison example, which is made of a material containing 20 volume % of alumina long fibers with a diameter of 10 μm.
Rotary tool No. 5 is a comparison example, which is made of a material containing approximately 76 volume % of glass long fibers.
Table 1 shows the results of the grinding test. Rotary tool No. 1 cut the workpiece approximately 1.4 mm deep while being moved back and forth 20 times. No clogging occurred, and the rotary tool was in a condition in which it could continue the operation with the same efficiency. Rotary tool No. 2 cut the workpiece 1.3 mm, without involving any clogging. Rotary tools 3 and 4 were inferior to Rotary tools 1 and 2 in terms of cutting depth, but involved little clogging due to their compact structure.
Rotary tool 5 proved very poor in terms of cutting depth because of its material containing glass fibers.
TABLE 1__________________________________________________________________________ Vol. % of CuttingTool No.Type of cutting elements elements contained Binder type Holes depth (mm) Clogging__________________________________________________________________________1 Aluminous fibers 60 Epoxy None 1.4 Noneφ15 μm2 Aluminous fibers 60 Epoxy None 1.3 Noneφ10 μm3 Aluminous fibers 20 Epoxy None 0.4 Noneφ15 μm4 Aluminous fibers 10 Epoxy None 0.3 Noneφ10 μm5 Vetreous fibers 76 Epoxy None -- Someφ23 μm__________________________________________________________________________
As is apparent from the above description, the rotary tool of this invention contains a large amount of hard inorganic long fibers, so that it has a fine cutting edge containing cutting elements in a high density. Accordingly, it is superior to conventional grindstones in terms of working efficiency.
Furthermore, the inorganic long fibers of the rotary tool of this invention are firmly retained by thermosetting resin, so that the tool can enjoy a long service life than grindstones, whose abrasive grains are subject to detachment.
Since the material of the rotary tool according to this invention is made compact and has no pores, it involves no clogging, always providing an excellent cutting quality.
By employing inorganic fibers with a small diameter, the rotary tool of this invention can have a fine cutting edge with high density, so that it is suitable for cutting workpieces with a fine and smooth section or obtaining a smooth polished surface.
In addition, since the rotating tip is formed integrally with the rotation shaft, the rotary tool of this invention has no joint section, so that it is easy to manufacture and provides a reliable degree of strength. | A rotary tool for cutting, drilling, grinding, or polishing metallic or non-metallic materials is made of a compact material, which consists of an inorganic fiber reinforced plastic containing 50 to 81 volume % of inorganic long fibers selected from the following group: alumina fibers, boron fibers, silicon carbide fibers, and silicon nitride fibers, the remaining portion of the compact material consisting of a thermosetting resin matrix. | 1 |
BACKGROUND
[0001] 1. Field of Invention
[0002] The present disclosure relates in general to a wellhead assembly for use in producing subterranean hydrocarbons. More specifically, the present disclosure relates to a wellhead assembly having high and lower pressure wellhead housings with sockets whose respective outer surfaces are generally cylindrical.
[0003] 2. Description of Prior Art
[0004] Subsea wells typically include outer low pressure housing welded onto a conductor pipe, where the conductor pipe is installed to a first depth in the well, usually by driving or jetting the conductor pipe. A drill bit inserts through the installed conductor pipe for drilling the well deeper to a second depth so that high pressure housing can land within the low pressure housing. The high pressure housing usually has a length of pipe welded onto its lower end that extends into the wellbore past a lower end of the conductor pipe. The well is then drilled to its ultimate depth and completed, where completion includes landing a casing string in the high pressure housing that lines the wellbore, cementing between the casing string and wellbore wall, and landing production tubing within the casing. The aforementioned concentrically stacked tubulars exert a load onto the lower pressure housing that is transferred along an interface between the high and low pressure housings. Moreover, tilting the stacked tubulars generates a bending moment along the interface.
SUMMARY OF THE INVENTION
[0005] Disclosed herein a wellhead assembly, which in one embodiment includes an annular low pressure housing having a lower end set in a sea floor. In this example, an upper socket surface is formed along a portion of an inner surface of the low pressure housing; axially spaced apart from the upper socket surface is a lower socket surface formed along a portion of the inner surface of the low pressure housing. The wellhead assembly further includes an annular high pressure housing coaxially disposed within the low pressure housing, an upper socket surface formed along a portion of an outer surface of the high pressure housing that is in contact with the upper socket surface on the low pressure housing and that selectively exerts a load against the upper socket surface on the low pressure housing to define an upper loading interface. A lower socket surface is on the outer surface of the high pressure housing that is axially spaced apart from the upper socket surface on the high pressure housing and is in contact with the lower socket surface on the low pressure housing. The lower socket surface on the high pressure housing selectively exerts a load against the lower socket surface on the low pressure housing to define a lower loading interface. A latch assembly is coupled to the low pressure housing and the high pressure housing between the upper and lower loading interfaces. In an alternate example, the upper and lower loading interfaces project axially in a direction that is substantially parallel with an axis of the wellhead assembly. Optionally, the upper and lower loading interfaces are radially offset from one another. The wellhead assembly can alternatively further include a channel formed on an outer surface of the high pressure housing between the upper and lower loading interfaces and a passage axially formed through the high pressure housing having an end in communication with the channel and a lower end in communication with an annulus between the high and lower pressure housings on a side of the lower loading interface opposite the channel. Included with this example is a passage radially extending through the lower pressure housing and in communication with the channel. In an example embodiment the latch is made up of a C-ring set in a groove provided on an outer surface of the high pressure housing. The latch may include a profile on an inner surface of the low pressure housing. A downward facing shoulder can optionally be included on an outer surface of the high pressure housing that contacts an upward facing shoulder on an inner surface of the low pressure housing when the high pressure housing lands in the low pressure housing.
[0006] Also described herein is a wellhead assembly that includes a low pressure housing mounted in a sea floor having a high pressure housing landed within. The high pressure housing has upper and lower radially thinner portions and a radially thicker portion disposed between and adjacent to the upper and lower radially thinner portions. An upper loading surface is provided on an outer surface of the radially thicker portion that terminates at a location where the radially thicker portion transitions into the upper radially thinner portion. A lower loading surface is formed on the outer surface of the radially thicker portion that terminates at a location where the radially thicker portion transitions into the lower radially thinner portion. Upper and lower loading surfaces are included on an inner surface of the low pressure housing that respectively engage the upper and lower loading surfaces on the radially thicker portion. A latch is provided for engaging the low and high pressure housings disposed axially between the upper loading surface and lower loading surface on the high pressure housing. An optional channel can be included on an outer surface of the high pressure housing disposed between the upper loading surface and lower loading surface on the high pressure housing and a passage providing communication between the channel and an annulus between the low and high pressure housings and adjacent the location where the radially thicker portion transitions to the lower radially thinner portion. In an alternate example included is a production tree on an upper end of the high pressure housing. Optionally included is a casing hanger landed inside the high pressure housing and a tubing hanger landed inside the casing hanger.
BRIEF DESCRIPTION OF DRAWINGS
[0007] Some of the features and benefits of the present invention having been stated, others will become apparent as the description proceeds when taken in conjunction with the accompanying drawings, in which:
[0008] FIG. 1 is a side sectional view of engaging together example embodiments of high and low pressure wellhead housings in accordance with the present invention.
[0009] FIG. 2 is a side perspective view of the high and low pressure wellhead housings of FIG. 1 in engagement to form a portion of an embodiment of a wellhead assembly and in accordance with the present invention.
[0010] FIG. 3 is a side sectional view of the portion of the wellhead assembly of FIG. 2 further including a production tree and in accordance with the present invention.
[0011] While the invention will be described in connection with the preferred embodiments, it will be understood that it is not intended to limit the invention to that embodiment. On the contrary, it is intended to cover all alternatives, modifications, and equivalents, as may be included within the spirit and scope of the invention as defined by the appended claims.
DETAILED DESCRIPTION OF INVENTION
[0012] The method and system of the present disclosure will now be described more fully hereinafter with reference to the accompanying drawings in which embodiments are shown. The method and system of the present disclosure may be in many different forms and should not be construed as limited to the illustrated embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey its scope to those skilled in the art. Like numbers refer to like elements throughout.
[0013] It is to be further understood that the scope of the present disclosure is not limited to the exact details of construction, operation, exact materials, or embodiments shown and described, as modifications and equivalents will be apparent to one skilled in the art. In the drawings and specification, there have been disclosed illustrative embodiments and, although specific terms are employed, they are used in a generic and descriptive sense only and not for the purpose of limitation.
[0014] FIG. 1 is a side sectional view of an example of a wellhead assembly 10 being formed by inserting a high pressure housing 12 into a low pressure housing 14 . A weld 16 on the high pressure housing 12 of FIG. 1 attaches an upper portion 18 to a lower portion 20 , where the lower portion 20 extends downward and into a wellbore 21 . Similarly, the low pressure housing 14 includes a weld 22 attaching an upper portion 24 to lower portion 26 . In the example of FIG. 1 , the lower portion 26 is anchored within a sea floor 27 . A transition 28 on the upper portion 18 indicates where its thickness changes. Below the transition 28 the thickness of the upper portion 18 is substantially the same as a thickness of the lower portion 20 , whereas above the transition its thickness increases to a maximum width to define a middle section of the high pressure housing 12 . An upper terminal end of the middle section is defined by an upper transition 29 , which indicates a location where the radial thickness of the high pressure housing 12 decreases. The radial thickness of the high pressure housing 12 above the transition 29 is less than along the middle section, but greater than below transition 28 . The changes in radial thickness define a thicker middle section with two radially thinner portions projecting axially away from the middle section. Further illustrated in the example of FIG. 1 is a passage 30 in the upper portion 18 that extends axially downward from a channel 31 shown circumscribing the middle portion along its outer surface. The passage 30 communicates between the channel 31 and an annulus between the high and low pressure housings 12 , 14 .
[0015] A lower socket surface 32 is shown formed on an outer periphery of the upper portion 18 and facing generally radially outward from an axis A X of the wellhead assembly 10 ; a lower end of the lower socket surface 32 terminates adjacent the transition 28 . The low pressure housing 14 also includes a lower socket surface 34 that is formed on an inner circumferential surface of the low pressure housing 14 . In the example of FIG. 1 , a lower end of the lower socket surface 34 terminates adjacent where the radial thickness of the low pressure housing 14 decreases to a thickness substantially the same as a thickness of the lower portion 26 . In one embodiment, a radial passage 36 is further illustrated that extends through the upper and thicker portion 24 of the low pressure housing 14 . In an example embodiment, the radial passage 36 is above an upper terminal end of the lower socket surface 34 .
[0016] Still referring to FIG. 1 , upper socket surface 38 is similarly provided on the outer surface of the high pressure housing 12 shown facing generally radially outward from the axis A X , and having an upper end that terminates adjacent transition 29 . An upper socket surface 40 on the low pressure housing 14 faces radially inward towards axis A X and has an upper terminal end proximate an upper terminal end of the low pressure housing 14 . As further discussed below, a latching system is included for coupling together the high and low pressure housings 12 , 14 that includes s C-ring 42 disposed within a groove 44 formed on the outer surface of the radially thicker section of the upper portion 18 . The C-ring 42 and groove 44 illustrate one example of embodiment of a latching mechanism for engaging the high and low pressure housings 12 , 14 .
[0017] Referring now to FIG. 2 , an example is illustrated of the high pressure housing 12 landed within low pressure housing 14 . In this example, the upper socket surfaces 38 , 40 are aligned and in contact with one another so that any bending moment forces exerted onto the high pressure housing 12 can be transferred onto the low pressure housing 14 . Axially distal from the upper socket surfaces 38 , 40 are the lower socket surfaces 32 , 34 , also in engagement and in contact with one another for effectively transferring bending moment loads from the high pressure housing 12 to low pressure housing 14 . In the embodiment illustrated, the lower socket surfaces 32 , 34 are a maximal distance from the upper socket surfaces 38 , 40 , thereby increasing bending moment transfer between the inner and outer wellhead housings 12 , 14 and consequently reducing respective angular movement of the high pressure housing 12 within low pressure housing 14 . When in the landed configuration of FIG. 2 , the passage 36 registers with channel 31 , so that passage 36 is in fluid communication with passage 30 and with the annulus between the high and low pressure housings 12 , 14 As shown, passage 36 and channel 31 are between the lower socket surfaces 32 , 34 and the upper socket surfaces 38 , 40 . Further shown in the example of FIG. 2 are load shoulders 45 , 46 respectively formed on the high and low pressure housings 12 , 14 , which are in axial contact with one another, thereby transferring an axial load from the high pressure housing 12 onto the low pressure housing 14 for supporting the high pressure housing 12 within low pressure housing 14 . Additionally, a profile 47 is shown formed on an inner surface of the low pressure housing 14 and strategically located so to engage an outer surface of the C-ring 42 for latching together the high and low pressure housings 12 , 14 . Moreover, by locating the latching mechanism of the C-ring 42 , along with the channel 31 , axially between the upper socket surfaces 38 , 40 and lower socket surfaces 32 , 34 , the maximal distance between the socket surfaces can be achieved. As such, forgings of the upper portions 18 , 24 need not be altered in order to achieve sufficient bending moment transfer between the housings 12 , 14 .
[0018] Another advantage of the wellhead housing 10 disclosed herein is that in one embodiment, the socket surfaces 32 , 34 , 38 , 40 each are generally vertical so that minimal forces are required to insert the high pressure housing 12 within low pressure housing 14 . In one example of use, axial forces required to urge the high pressure housing 12 inside low pressure housing 14 were less than about 200,000 pounds force.
[0019] FIG. 3 is a side sectional view of an example of the wellhead assembly 10 shown with a production tree 48 mounted on an upper end of the high pressure housing 12 . Further illustrated is a casing hanger 50 landed on an inner surface of the high pressure housing 12 and supporting a string of casing 52 shown depending downward into the wellbore 21 . Coaxially inserted within the casing 52 is a tubing hanger 54 having a corresponding string of tubing 56 that projects coaxially within the casing 52 . Thus, in this example, the low pressure housing 14 axially supports the load of the high pressure housing 12 tubing and casing hangers 50 , 54 , casing 52 , and tubing 56 . Further in the example of FIG. 3 , the tubing communicates with a main bore 58 that projects axially through the production tree 48 .
[0020] In one optional example, one of the socket surfaces can have a convex shape while an opposing or mating socket surface can still have a cylindrical or substantially vertical profile. Similarly, both the inner and outer socket surfaces may have convex shapes that deform when the high pressure housing 12 inserts and lands within the low pressure housing 14 . In another optional embodiment, one of the socket team members can be in a separate housing where the housing is welded to the member holding the other socket surface.
[0021] The present invention described herein, therefore, is well adapted to carry out the objects and attain the ends and advantages mentioned, as well as others inherent therein. While a presently preferred embodiment of the invention has been given for purposes of disclosure, numerous changes exist in the details of procedures for accomplishing the desired results. These and other similar modifications will readily suggest themselves to those skilled in the art, and are intended to be encompassed within the spirit of the present invention disclosed herein and the scope of the appended claims. | A wellhead assembly for use subsea includes a high pressure housing landed within a low pressure housing. The low pressure housing is an annular member that mounts into the sea floor and having an inner surface engaging the high pressure housing along a loading interface. Upper and lower sockets are formed along axially spaced apart portions of the outer surface of the high pressure housing. As the high pressure housing inserts into the low pressure housing, the high pressure housing sockets engage corresponding sockets formed along axially spaced apart sockets on portions of the inner surface of the low pressure housing. The sockets each have cylindrically shaped outer surfaces, and when engaged with one another define the loading interface. The sockets are strategically located on the upper and lower portions of the housings to maximize their distance apart. | 4 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a division of U.S. application Ser. No. 13/754,295, filed Jan. 30, 2013, and is based upon and claims the benefit of priority from United Kingdom Patent Applications No. 1205761.8, filed Mar. 30, 2012 and No. 1222726.0, filed Dec. 17, 2012, the entire content of each of the foregoing applications is incorporated herein by reference.
BACKGROUND OF THE DISCLOSURE
1. Field of the Disclosure
The present disclosure relates to a method, device and computer program product for outputting a transport stream.
2. Description of the Related Art
At present consumers have the opportunity to view televisual content over the Internet using a so-called “video on demand” system. This type of system enables a user to select video content to view over the Internet. This video content may include televisual broadcasts previously broadcast. One example of this is iPlayer provided by the British Broadcasting Corporation (BBC).
However, in order to access this content, the televisual broadcast must be completed and uploaded to the server by the video on demand service. This provides an inconvenience for the viewer.
Embodiments of this disclosure may address this issue.
SUMMARY
Embodiments of the disclosure provide a software application linking broadcast content to corresponding content available on a server. The corresponding content may be segmented into portions. The corresponding content may be substantially time aligned to the broadcast content, allowing for latency in the assembly of the content and/or delivery systems.
According to one aspect of the present disclosure, there is provided a method comprising: receiving, via a broadcast channel, video data having an identifier that identifies a position within the video and an address defining the location of a stored playlist; obtaining from a server the playlist in response to a user input, the playlist containing location information identifying the location of a stored transport stream; receiving the transport stream from the location identified in the playlist over a network; and displaying the obtained transport stream.
Embodiments of the disclosure may allow the user to interact with broadcast content to provide additional functionality to the content.
The stored transport stream may include at least one frame of said video data corresponding to that received over the broadcast channel. Embodiments of the disclosure may allow the user to effectively perform operations on the content such as pause, rewind, fast forward etc.
The method may further comprise storing the video data obtained over the broadcast channel concurrently with displaying the transport stream obtained from the server; performing a transition back to the received video data by increasing the speed of playback of the transport stream; stopping display of the transport stream; and displaying the stored video data with an increased playback speed. Embodiments of the disclosure may enable smooth transition upon returning to the broadcast content.
The method may further comprise storing the video data obtained over the broadcast channel; stopping display of the transport stream and displaying the stored video data. This may reduce the discontinuity between switching from server based content to broadcast content.
The transport stream may include a plurality of transport stream clips, each transport stream clip being of a predetermined clip duration; provide the location of each of the transport stream clips and the duration of each of the transport stream clips in the playlist, and the method may include selecting the transport stream clip to be retrieved in accordance with the duration of each of the transport stream clips provided in the playlist and the identifier of the position within the video; and retrieving the selected transport stream clip.
The identifier may be a video timestamp.
According to another aspect, there is provided a computer program containing computer readable instructions which when loaded onto a computer configures the computer to perform a method according to any embodiment.
A storage medium which is configured to store the computer program of the aspect therein or thereon is provided.
According to another aspect, there is provided a device comprising: a receiver configured in use to receive, via a broadcast channel, video data having an identifier that identifies a position within the video and an address defining the location of a stored playlist; a network connector configured in use to obtain from a server the playlist in response to a user input, the playlist containing location information identifying the location of a stored transport stream; wherein the network connector is further configured in use to receive the transport stream from the location identified in the playlist over a network; and an output configured in use to output the obtained transport stream for display.
The stored transport stream may include at least one frame of said video data corresponding to that received over the broadcast channel.
The device may further comprise a memory configured in use to store the video data obtained over the broadcast channel concurrently with displaying the transport stream obtained from the server; and a controller configured in use to perform a transition back to the received video data by increasing the speed of playback of the transport stream; stop display of the transport stream; and to output the stored video data for display with an increased playback speed.
The device may further comprise a memory configured in use to store the video data obtained over the broadcast channel; and a controller configured in use to stop display of the transport stream and to output the stored video data for display.
The transport stream may include a plurality of transport stream clips, each transport stream clip being of a predetermined clip duration and the playlist provides the location of each of the transport stream clips and the duration of each of the transport stream clips in the playlist; the device may further comprise a controller configured in use to select the transport stream clip to be retrieved in accordance with the duration of each of the transport stream clips provided in the playlist and the identifier of the position within the video; and the network connector is configured in use to retrieve the selected transport stream clip.
The identifier may be a video timestamp.
There is also provided a television comprising a display and a device according to any one of the embodiments.
BRIEF DESCRIPTION OF THE DRAWINGS
The above objects, features and advantages of the disclosure will be apparent from the following detailed description of illustrative embodiments which need to be read in connection with the accompanying drawings, in which:
FIG. 1 shows a system according to embodiments of the present disclosure;
FIG. 2 shows a television according to embodiments of the present disclosure;
FIG. 3 shows representative screenshots of embodiments of the present disclosure;
FIG. 4 shows the structure of a look-up table stored in the server according to embodiments of the present disclosure;
FIG. 5 shows the structure of a playlist according to embodiments of the present disclosure;
FIG. 6 shows a flow diagram explaining the encoding of the televisual content according to embodiments;
FIG. 7A shows a flow diagram explaining the viewing of live rewind according to embodiments of the present disclosure when the live rewind is viewed on the television;
FIG. 7B shows a flow diagram explaining the viewing of live rewind according to embodiments of the present disclosure when the live rewind is viewed on a tablet;
FIG. 8 shows a plan view of a tablet in use to control the video stream; and
FIGS. 9A to 9F show different gestures to control the tablet.
DESCRIPTION OF EMBODIMENTS
Referring to FIG. 1 , a system 100 according to an embodiment of the present disclosure is shown. In this system 100 , a camera 105 captures video and/or audio content. The output of the camera 105 is typically edited in an editing suite (not shown). The captured (and possibly edited) content in encoded in an encoder 110 .
In embodiments, the content is encoded using, for example, the Moving Pictures Expert Group (MPEG) 2 format. However, the disclosure is not limited to such a format and any other video and/or audio format is envisaged.
The encoded content is fed into a multiplexor 115 . The multiplexor 115 multiplexes the received encoded video and/or audio data with other data. In embodiments, the other data includes an identifier that uniquely identifies the broadcast program and a Hybrid Broadcast Broadband TV (HBBTV) URL. As the HBBTV programming language is known to the skilled person, a detailed discussion of the HBBTV programming language will not be provided. However, the HBBTV URL is an .html link which identifies the location of a HBBTV application. However, the skilled person will appreciate that the HBBTV URL may be an index.php, main.cgi, application.asp or the like. The identifier is, in embodiments, a video timestamp, although any type of identifier that identifies the video is also envisaged. The identifier may uniquely identify the frame of video for a very accurate playback or may indicate the approximate location of a particular frame of video. For example, the location of a particular frame may be approximately determined using the nearest video timestamp.
The other data, in embodiments, is inserted in the private field of the MPEG 2 transport stream adaptation field. In order to indicate that the private field of the MPEG 2 transport stream adaptation field has data contained therein, the transport private data flag is set to 1 as would be appreciated by the skilled person.
In addition, the other data may include metadata such as the Event Information Table (EIT) that provides Electronic Program Guide (EPG) information. Additionally, closed caption information may also be included with the metadata. The EIT and closed caption information is known to the skilled person and are defined by the various Digital Video Broadcast (DVB) standards. Of course, corresponding tables are also available in other transmission standards which are equally applicable to embodiments of the present disclosure. Examples of these standards include ATSC and ARIB.
Of course, in embodiments, although the other data and the metadata is inserted into the private field of the MPEG 2 transport stream adaptation field, the other data and metadata may be inserted in any appropriate part of the transport stream.
The multiplexor 115 is connected to a database 145 . In the database 145 is stored the video timestamps which are used to identify the video in the transport stream and a triplet of information including the original network identifier (ONID), transport stream identifier (TSID) and the service identifier (SID) associated with the timestamp. The video timestamps are retrieved by the multiplexor 115 .
The multiplexed MPEG2 transport stream is fed to a broadcast station 150 . The broadcast station 150 is a terrestrial broadcast station. However, as would be appreciated, the broadcast station 150 may be a satellite broadcast station, cable television broadcast station or indeed any broadcast station such as a broadcast station broadcasting to handheld devices complying with, for example, the Digital Video Broadcast-Handheld (DVB-H) format. Other broadcast modes and/or standards may equally be used.
The broadcast station 150 broadcasts the multiplexed MPEG2 transport stream over the air 155 . The broadcast signal is received by an antenna 160 within the user's home. The received multiplexed transport stream is fed to television 140 . Television 140 will be described in more detail with reference to FIG. 2 .
Additionally, the multiplexor 115 multiplexes the encoded MPEG2 content to generate a number of MPEG2 transport stream files. In other words, the multiplexor 115 splits the encoded MPEG2 transport streams into a plurality of segments and for each segment, the multiplexor 115 generates a transport stream file. These transport stream files will be used to enable a viewer to download video such that the user may “rewind” or perform other function on the broadcast content. Although this will be explained later, it should be noted that the generation of MPEG2 transport stream files is to comply with the particular protocol used (HTTP Live Streaming) used to deliver the content to the television. If a different protocol is used, such as MPEG2 Dynamic Adaptive Streaming, then the generation of the transport stream files may be un-necessary or may be different.
In embodiments, the multiplexor 115 segments the transport stream into a plurality of transport stream files; each file containing 8 seconds of encoded video. Additionally created by the multiplexor 115 is a playlist file. The playlist file will be explained in more detail with reference to FIG. 5 . However, in brief, the playlist file contains a pointer to each of the created transport stream files and complies with the HTTP Live Streaming format. The pointer stored within the playlist file may be a URL or a URI (Unique Resource Identifier).
The multiplexor 115 stores the created transport stream files and the playlist file in a server 120 . The server 120 is accessible over the Internet or any kind of network 130 . Such a network may or may not have quality of service guarantees. In FIG. 1 , it is immediately apparent that the server 120 stores the playlist 126 (see FIG. 5 ), a HBBTV look-up table 122 (see FIG. 4 ) and the video transport stream files 124 . As will be explained later, a router 135 which is also connected to the television 140 accesses the information stored within the server 120 via the Internet 130 .
The television 140 is controlled by a user operating a user control 205 . The user control 205 may be a remote commander or the like. However, the user control 205 may be an application running on a portable computing device such as a Tablet S produced by Sony®. Voice activated or gesture based commands may provide an alternative and in some embodiments may obviate the need for a physical user control 205 . The user control 205 communicates with a control receiver 210 that decodes the control signals received from the user control 205 . The control receiver 210 is connected to the controller 215 which controls the operation of the television 140 . Also connected to the controller 215 is a decoder 240 . The decoder 240 is connected to the antenna 160 and decodes the broadcast signal received from the broadcast station 150 . The decoded signal is fed to the controller 215 . In embodiments, the decoder includes a tuner and demodulator.
In order to display the video, the controller 215 provides video and/or audio data received from the decoder 240 to an audio and/or video (A/V) processor 220 . The A/V processor 220 generates audio signals to be played over speakers (not shown) and video signals to be reproduced on display 225 . The display 225 may be a liquid crystal display type display such as a Sony® Bravia® television.
Also connected to the controller 215 is memory 230 . The memory 230 may be built in to the television or may be provided externally. The memory 230 is, in embodiments, solid state memory, but the disclosure is not limited and may be any kind of memory such as optically readable or the like.
The memory 230 stores computer readable instructions which are in the form of a computer program. The computer program stored within the memory 230 controls the controller 215 to perform a method according to embodiments of the present disclosure. Additionally, and as will be explained later, the memory 230 acts as a buffer to store transport streams that the television 140 retrieves from the server 120 .
The controller 215 is also connected to an internet connector 235 . In embodiments, the internet connector 235 is an Ethernet connector. The internet connector 235 is connected to the router 135 . Of course, embodiments of the present disclosure may be applied to any kind of network connection. For example, the internet connector 235 may be wired, wireless, Powerline or HomePlug® or a 3G/4G network.
Additionally a tablet 800 communicates with the television 140 . The tablet 800 may be any kind of tablet computer such as a Sony® Tablet S or a Sony® Xperia® Tablet S which may or may not also operate as the user control 205 . The tablet 800 may communicate using Bluetooth or any kind of wired or wireless connection. The operation of the tablet 800 will be described in more detail with reference to FIGS. 7B and 8 .
FIG. 3 shows a sequence of screen shots illustrating the operation of embodiments of the present disclosure. A television signal is received at the antenna 160 . The television 140 receives this signal and displays the associated video frame or sequence of video frames. A first image 305 in an image sequence 300 is displayed to the user. The first image 305 shows a frame of live content. In other words, the first frame 305 is a frame of video currently being broadcast by the broadcast station 150 .
At this time, the viewer of the television 140 decides that he or she wants to rewind the currently broadcast video. In order to interact with the currently broadcast content, the user presses a button on the user control 205 . This button may be the so-called “red button”. The live video stream continues and a Graphical User Interface (GUI) is shown on the display. This is shown in the second frame 310 . The GUI is generated using a HBBTV application stored within the server 120 . In order to obtain the HBBTV application, the television 140 retrieves the HBBTV URL which is located in the transport stream broadcast by the broadcast station 150 . The HBBTV URL provides the location of the HBBTV application which is downloaded by the television 140 over the network 130 . In other words, when the television 140 decodes the incoming transport stream broadcast by the broadcast station, the HBBTV URL directs the television 140 to the location of the HBBTV application stored on the server 120 . The television 140 then downloads the HBBTV application from the server 120 and stores this locally in the storage memory 230 .
The downloaded HBBTV application provides the code to display the GUI on the screen. It is envisaged that the HBBTV application may be updated by the broadcast station 150 that allows the GUI to be customised, such as advertising sponsors logos being included in the GUI.
Once the HBBTV application has loaded, the user may control the video controls in the GUI using the user control 205 . In the example embodiment, the user wishes to rewind the broadcast content. This is indicated by the dashed lines 316 surrounding the rewind symbol in the GUI in the third frame 315 .
As will be explained later, the URL stored in the look-up table 125 is used to access a playlist. This URL is called the “Playlist URL” hereinafter. The playlist is then used to control the content displayed on the television 140 . In order for the playlist and the appropriate content to be downloaded into the memory 230 of the television 140 , the screen will be frozen for a period of time. This is because the broadcast content is segmented into 8 second segments and then stored on server 120 . Therefore, if the broadcast content is live content, the user may have to wait up to 8 seconds until the segment of live video is completed and a further small time, t to allow the segment to be saved, the playlist to be updated and the segment to be downloaded by the television. Accordingly, given the length of time to wait, an egg-timer 321 is displayed in the corner of the frozen screen as shown in the fourth frame 320 to indicate to the user that the application is being downloaded. Although an egg timer is shown, any other kind of message may be displayed. This may include a message asking the viewer to please wait or even an advertisement. If an advertisement is provided the broadcaster may transmit the advertisement at the start of the broadcast and the advertisement may be stored in memory 230 of the television 140 . The advertisement may be provided via the network at that time or in advance. The broadcaster may therefore generate income by selling the advertisement opportunity to a sponsor.
In the event that the broadcast content is pre-recorded, the delay described above with respect to the live content does not occur. This is because the video timestamps, playlist and video transport stream files have already been created and stored on the server 120 . However, when the recorded content is broadcast, the playlist will be modified in order to correspond to the current broadcast content. In other words, the initial playlist for the recorded content (i.e. the playlist when the content was created) will have changed when the recorded content is broadcast. The playlist stored on the server 120 will need to be updated accordingly.
After the user selects the rewind symbol using the user control 205 , the television 140 retrieves the appropriate transport stream from the server 120 as will be explained later. After the appropriate data is downloaded to the television 140 from the server 120 , the egg-timer will stop being shown and instead the television 140 will display the transport stream obtained from the server 120 . The transport stream obtained from the server 120 will be the transport stream nearest in time to the transport stream of the frame currently being broadcast. During the operation of the GUI, the video displayed to the user is the transport stream provided by the server rather than the video broadcast by the broadcast station 150 .
In order to indicate to the user that the video being displayed is that provided by the server 120 rather than the broadcast station 150 , a message may be displayed to the user. This message may include textual or graphical information indicating that the video is provided by the server 120 rather than by the broadcast station 150 . For example, if the indication to the user is graphical, a time or clock showing the elapsed time between the content provided by the server 120 and the content provided by the broadcast station 150 may be displayed. This elapsed time may be derived from the video timestamps or some other mechanism. The user may be able to toggle whether to show this information or not.
When the user wishes to start playback of the video obtained from the server 120 , the user highlights the playback button 326 shown in the fifth frame 325 . The user then selects the playback button 326 and the video content is played back. It is important to note that the content during this period is the content downloaded from the server 120 rather than the content being broadcast by the broadcast station 150 .
When the user wishes to return to the live content (i.e. the content being broadcast by the broadcast station 150 ), the user can press the red button again. However, it is useful for a more seamless experience for the user to press a stop button on the GUI (not shown). As the HBBTV application must revert to displaying content broadcast by the broadcast station 150 , the egg timer is shown again in the sixth screen 330 . The content displayed on the television 140 then returns to the live content being broadcast by the broadcast station 150 in the seventh screen 335 .
As noted in FIG. 3 , after the user starts the HBBTV application and selects to rewind the broadcast content, a short delay occurs (see the fourth screen shot 320 ). During this delay, the HBBTV application retrieves the video timestamp and a DVB triplet from the transport stream. The HBBTV application also retrieves the playlist URL indicating the location of the playlist from the server 120 . The HBBTV application in the television 140 accesses the server 120 over the Internet 130 . The HBBTV application accesses the HBBTV lookup table 122 within the server 122 . The HBBTV lookup table 122 is shown in FIG. 4 .
Referring to FIG. 4 , the DVB triplet which identifies a particular broadcast program is stored in the HBBTV look-up table. Specifically, the DVB triplet is stored in a triplet column 125 A of the look-up table. Additionally stored in a playlist URL column 125 B is the playlist URL. The playlist URL is stored in correspondence with the DVB triplet. The playlist URL provides, in embodiments, an .html link to the location of the playlist for the program that is associated with the DVB triplet (although other forms of pointer are envisaged). In embodiments, the playlist is stored within the server 120 .
Additionally, the playlist stored at the location associated with the playlist URL is retrieved.
FIG. 5 shows a playlist according to embodiments of the present disclosure. The playlist (.m3u8), in embodiments complies with the HTTP Live Streaming protocol, although the disclosure is not so limited and any appropriate protocol is envisaged. Although this would be appreciated by the skilled person, the “EXT-X-TARGETDURATION” value is set to 8. This means that, in this case, each transport stream is 8 seconds long. However, the value of “EXT-X-TARGETDURATION” can be varied to any value. The value of this determines the length of the transport stream file. For example, if the value of “EXT-X-TARGETDURATION” is 2, the transport stream file is 2 seconds long. This value can be any suitable value such as 2 seconds or 10 seconds or the like.
Further, a transport stream file URL is provided in the playlist to each of the transport streams. Therefore, by following the transport stream file URL the appropriate 8 second video segment may be downloaded.
It will be appreciated that the content being broadcast by the broadcast station 150 will be stored in 8 second segments within the server 120 . Each 8 second segment will have a transport stream file unique URL. After the creation and storage of the 8 second segment, the transport stream file URL will be stored within the playlist. This means that the playlist is dynamically updated during the broadcast of the program.
The encoding of the content according to embodiments will be described with reference to the flow chart 600 of FIG. 6 . Firstly, the content is captured 605 . The captured content is encoded to produce an MPEG2 transport stream in step 610 . The encoded data is then fed to the multiplexor 115 which produces a transport stream for broadcast and a separate transport stream for storage on the server 120 .
The transport stream for broadcast is produced in step 615 . Specifically, the multiplexor 115 multiplexes the encoded captured content with the other data (the HBBTV URL and the video timestamp). Additionally, the multiplexor 115 may include metadata such as the EIT and the like in the transport stream. The multiplexed encoded data is then broadcast using the broadcast station 150 .
The multiplexor 115 also produces data for storage on the server 120 . Specifically, the multiplexor 115 generates the HBBTV look-up table 125 which stores the DVB triplet in association with the playlist URL. Also, the multiplexor 115 generates the 8 second transport stream clips and stores these on the server 120 . The associated playlist is also updated to include a link (the transport stream URL) to the newly created 8 second clip of the transport stream by the multiplexor 115 . The updated playlist file and the 8 second clips are uploaded back onto the server 120 . This is shown in steps 625 , 630 and 635 of FIG. 6 .
The encoding steps end at step 640 .
A flow diagram 700 explaining the operation of the system according to embodiments is shown in FIGS. 7A and 7B . A user switches the television 140 on and chooses an appropriate channel in step 705 . The television 140 receives the multiplexed stream via the antenna 160 . The received stream is demultiplexed in step 710 . The demultiplexed stream is decoded and viewed on the television in step 715 . Additionally, in step 717 , the television 140 retrieves the HBBTV URL from the transport stream and downloads the HBBTV application from the server 120 . The HBBTV application is stored in memory 230 within the television 140 . The television 140 also executes the HBBTV application at step 720 . As the television 140 executes the HBBTV application prior to the user pressing the red button to activate the GUI, the time taken for the television 140 to respond to the user input is significantly reduced.
The decision point at step 725 is then reached. If the user does not wish to launch the interactive GUI, the user does not press the red button and so the “no” path is followed. The user continues to watch the broadcast transport stream. However if the user does press the red button to launch the interactive GUI, the “yes” path is followed. At this point a second decision point at 727 is reached. This decision point determines whether the tablet or the television displays the video played back from the server.
If the television 140 plays back the video from the server, the HBBTV application shows the GUI on the screen of the television 140 . This is step 730 . As previously mentioned, the content displayed on the television 140 will be the broadcast content.
The user chooses to “rewind” the content in step 735 . Therefore, the user selects the appropriate icon on the GUI. After the selection of the appropriate icon is made, the frame is frozen on the screen of the television 140 and the egg-timer or appropriate message is displayed.
The HBBTV application retrieves the video timestamp and the DVB triplet from the frozen video frame. This is step 740 . Using the look-up table, the playlist URL corresponding to the retrieved triplet is followed. This is step 745 . The playlist stored at the retrieved playlist URL is downloaded. This is step 750 .
As the retrieved playlist contains links to many 8 second transport streams, the television must determine which of the stored transport streams includes the frozen frame.
In order to do this, the television compares the retrieved video timestamp with the sum of the 8 second transport stream clips. In other words, if the video timestamp indicates that the frozen frame is, say, 817 seconds from the start of the broadcast, then the appropriate frame will be located within the 103 rd transport stream within the playlist. In other words, for transport stream clips 8 seconds long, the frame that is 817 seconds from the start of the broadcast will be located approximately 1 second into the 103 rd transport stream. This is step 755 . The television 140 then retrieves, in this case, the 103 rd transport stream identified in the playlist. This is step 760 . After downloading the 103 rd transport stream, the television identifies the approximate location of the frozen frame using the video timestamp. This approximate location is determined as being the video timestamp in the stored transport stream being closest to the video timestamp retrieved from the frozen image. This is step 765 . The television 140 then rewinds from the location. This is step 770 . The process for rewinding ends when the user presses the play button in the GUI. This is step 775 .
The user then watches the content from the server 120 . When the user wishes to return to watching the broadcast content, the user presses the red button or the button on the GUI. The HBBTV application may simply finish and return to displaying the broadcast content. However, as the content is concurrently broadcast, the time taken to return to viewing the broadcast content may result in a discontinuity in viewing of the content.
In order to reduce the effect of the discontinuity, a transition process is followed. Specifically, the memory 230 within the television 140 is, in embodiments, used as a buffer to store some of the video broadcast by the broadcast station 150 . The memory 230 may be used to store all the video broadcast by the broadcast station, or may be used to store only certain frames of the video. For example, the memory 230 may be used to store only I-frames. However, when using the memory 230 as a buffer, the video broadcast by the broadcast station 150 will always be buffered by the memory 230 irrespective of whether the content being displayed is actually being provided by the server 120 .
The memory 230 , in embodiments, stores, and buffers 8 , seconds of video. In other words, although the memory 230 could store any length of video, in embodiments, the amount of video stored by the memory 230 is the same as the length as one of the transport stream files. The video stored in memory 230 is then used to reduce the impact of the discontinuity.
In one mechanism of operation of the transition process, when the user wishes to return to viewing broadcast content, the 8 second transport stream file retrieved from the server 120 is played back at twice the normal speed. This means that the 8 second transport stream file is played back in 4 seconds.
The next 8 seconds of broadcast content is then played back from the memory 230 at twice the normal speed. In other words, the next 8 seconds of broadcast content are provided by the memory 230 rather than the server 120 and is played back within 4 seconds. Thus, when viewing of live broadcast content resumes after this transition, the effect of the discontinuity is reduced to zero time lag. In order to reduce the effect of the increased speed of playback and in order to reduce the memory usage, it is possible to only play back I frames during this speeded playback period.
In a second mechanism of operation, if the user has requested that the television 140 rewind the live content, in embodiments, the television 140 will continuously store 8 seconds of buffered content from the broadcast station 150 . Therefore, when the user switches back to watching live content, the content will be provided by the buffer in the memory 230 rather than being provided by the antenna 160 directly. In other words, the user will watch video content that is delayed by 8 seconds compared to the content received by the antenna 160 . This arrangement removes all discontinuities and requires no speeding up of displayed content.
In other modes of operation, a so-called buffer flush may be employed upon detection of selection signals from the user to allow a swift transition between the content stored in the respective buffers. This operates by repositioning a pointer to the location in memory that should be read.
In the case that the tablet 800 plays back the content, the flow diagram of FIG. 7B is followed. Before the flow diagram of FIG. 7B is described, the interaction of the tablet 800 and the television 140 will be described.
In embodiments, the television 140 which receives both the broadcast channel and the transport stream from the server itself acts as a server to the tablet 800 . The television 140 may transmit either the video data from the broadcast channel, the transport stream identified by the playlist or both. It is therefore possible for the broadcast channel to be displayed on both the television 140 and the tablet 800 .
So, after connection of the tablet 800 to the television 140 , the television 140 receives the broadcast channel. The television 140 then acts as a server from which the tablet 800 receives content. The television 140 sends video data in a unicast fashion to the IP address to which the tablet 800 is connected. Obviously, if more than one tablet is connected to the television 140 , video data can be transferred in a unicast or multicast fashion. This allows video data from either the broadcast channel or the transport stream (or both) to be played back on the tablet 800 .
Returning to FIG. 7B , when the tablet 800 is used to control the video played back from the server, step 1730 is performed. The tablet may obtain the HbbTV application or be capable of storing and executing a separate application for example defining the GUI. The Tablet may an appropriate application for example in HTML from the server. This may be achieved by passing a URL from the HbbTV application in the television 140 to tablet 800 . The tablet 800 shows the GUI on the screen as depicted in FIG. 8 . As is seen in FIG. 8 , the current video 1315 is shown on tablet 800 . The GUI has a control bar 810 that appears and allows the user 810 to control the displayed video. In this case, the user 810 presses the rewind button 1316 displayed on the screen of the tablet 800 . In other words, the user performs step 1735 of FIG. 7B . It should be noted here that although the GUI displays a control bar 810 , in other embodiments, other control mechanisms are envisaged. These are described with reference to FIGS. 9A and 9F and will be described later.
The tablet 800 sends to the television 140 a control signal using, for example, Real Time Streaming Protocol (RTSP). The control signal instructs the television 140 that the user wishes to rewind from the frame displayed on the tablet 800 . As the television 140 sends the video to the tablet 800 , the television 140 then returns to the flowchart of FIG. 7A from step 740 by retrieving the ONID/TSID/SID from the broadcast stream.
The television 140 retrieves the video from the server and rather than playing back the video transport stream on the television 140 , the television transfers the retrieved video on the tablet 800 whilst the television either pauses the broadcast channel allowing the user to continue watching the television 140 later, or continue to display the live broadcast channel concurrently with the user viewing the retrieved video transport stream on the tablet 800 .
In other embodiments the server may communicate directly over the IP network with the tablet. The tablet may therefore be seen as a slave to the server rather than as a slave to the television 140 .
FIGS. 9A to 9F show different examples of control mechanisms which do not require the control bar 810 . These control mechanisms mean that more screen space is provided to display the video.
In FIG. 9A , the mechanism for skipping to the next chapter of video is shown. The user 810 places two fingers 810 A and 810 B on the touch sensitive screen of the tablet 800 . The user 810 then swipes their fingers to the left whilst still touching the screen. The tablet 800 detects both fingers touching the screen and detects the movement to the left. The tablet 800 then issues the command to move the video to the previous chapter. A similar situation is given in FIG. 9F except the user 810 swipes their fingers 810 A and 810 B to the right to advance the video to the next chapter.
In FIG. 9B , the mechanism for rewinding the video is shown. The user 810 places one finger 810 A on the touch sensitive screen of the tablet 800 . The user 810 then swipes their finger to the left whilst still touching the screen. The tablet 800 detects that only a single finger touches the screen and detects the movement to the left. The tablet 800 then issues the command to rewind the video. In this case, the speed at which the user swipes their finger determines the speed of rewind. For example, if the user only wishes to rewind the video at ×2 speed, then the swipe should be slow. However, for a ×30 rewind, the swipe should be fast. A similar situation is given in FIG. 9E except the user 810 swipes their finger 810 A to the right to fast forward the video.
In FIG. 9C , the mechanism for pausing the video is shown. The user 810 places two fingers 810 A and 810 B on the touch sensitive screen of the tablet 800 . The user 810 then holds their fingers on the screen for a period of time such as 0.3 seconds without movement. The tablet 800 detects both fingers touching the screen and that there is no movement. The tablet 800 then issues the command to pause the video.
In FIG. 9D , the mechanism for playback of the video is shown. The user 810 places one finger 810 A on the touch sensitive screen of the tablet 800 . The user 810 then holds their finger on the screen for a period of time such as 0.3 seconds without movement. The tablet 800 detects that one finger touches the screen and that there is no movement. The tablet 800 then issues the command to playback the video.
Although the foregoing describes controlling the video in relation to this disclosure, the touch screen commands of FIGS. 9A to 9F could be used on any touch screen device to control playback of any video on any video playback device. For example, the gestures given in FIGS. 9A to 9F could be used to control a DVD player, a Blu-Ray player, a video streaming device or any kind of device where video and/or audio playback needs to be controlled.
Although the foregoing embodiments, a broadcast channel has been described. However, in some video distribution environments, video data or television signals can be distributed over the internet or networks operating internet protocol technologies. These are sometimes referred to as IPTV or OTT (Over the Top) services. In IPTV, a managed network with a guaranteed quality of service may be used. With OTT, IPTV video data is carried over the internet and is available through, for example, the xDSL (Digitial Subscriber Line) subscription of Long Term Evolution (LTE) subscription of the user.
In IP environments, video may be distributed in a unicast fashion. In this type of system, video is distributed in a point-to-point manner from a server to a target device. The video is passed to the target device using a receiver such as a modem, router or home gateway device.
In other embodiments, video may be distributed using multicast protocols. Groups of target devices may be predefined or actively defined by making requests to join multicast groups. This may be in exchange for payment. Video data is then distributed using multicast identifiers or addresses contained therein with header information or the like. The target devices belonging to the multicast group then identifies and interpret the video data packets received via the network. Other devices will ignore the packets. The skilled person will appreciate that multicast transmission will save bandwidth when multiple devices are receiving the same video content items. The disclosure is applicable to multicast channels in a similar way to broadcast channels. Therefore, although broadcast channels are noted above, the disclosure is relevant to multicast channels or any type of distribution channels. The stored transport stream which the playlist identifies may be sent to the target devices using unicast protocols.
Although the foregoing has been described with reference to a tablet 800 , any kind of device with a screen is envisaged. For example, a cell phone, laptop computer or the like could be used instead of or as well as the tablet 800 .
Although the foregoing has been explained with reference to the transport streams on the server being produced from the captured content being broadcast, the disclosure is not so limited. For example, the transport streams on the server may include the broadcast content being captured from a different camera angle or level of zoom. Or, the transport stream on the server may include content related to the broadcast content. For example, if the broadcast content is a movie, the content on the server referenced by the playlist may be director's commentary.
Although the foregoing has been explained with the playlist complying with the HTTP Live Streaming Protocol, the disclosure is not so limited. Other suitable protocols include MPEG DASH or Microsoft Smooth Streaming or the like.
Although the foregoing has been described with reference to the video timestamp being used as the unique identifier, the disclosure is not so limited. Any unique identifier that enables the location of the frame to be established within the playlist may be used. For example, if the EIT is part of the broadcast transport stream, the elapsed time from the start time of the EIT may be used. Indeed, if other metadata such as the unique time code (UTC) in the TDT/TOT (Time and Data Table/Time Offset Table) is provided in the other data, this may be used.
Although the foregoing has been explained with reference to the user rewinding the broadcast content, the disclosure is not so limited. The user may pause the broadcast content, may fast forward the content (by skipping frames), may play back the content in slow motion or indeed perform any review of the content.
Although the foregoing has been explained with reference to the transport stream provided by the server 120 being displayed instead of the transport stream provided by the broadcast station 150 , the disclosure is not so limited. The transport stream provided by the server may be provided in addition to the broadcast transport stream. For example, the transport stream provided by the server 120 may be displayed in a picture-in-picture arrangement with the content provided by the broadcast station 150 . This allows the user to view the obtained transport stream concurrently with the broadcast transport stream.
Although the foregoing has been explained with HBBTV being used for the GUI, the disclosure is not so limited and any kind of appropriate programming language such as Adobe Flash or MHEG may be used instead.
Although the foregoing explains the use of a look-up table whereby the DVB triplet is stored in association with the playlist URL, the disclosure is no way limited. Indeed, if the broadcaster wishes to only associate one playlist with one channel, the playlist URL may be included in the broadcast transport stream. In this case, no look-up table is required.
In some embodiments the HBBTV application may restrict fast-forwarding of the content. This allows files to be uploaded to the server 120 in advance, but restricts fast-forwarding so that a viewer cannot watch content from the server 120 that has yet to be broadcast. | A method comprising: receiving, via a distribution channel, video data having an identifier that identifies a position within a video and an address defining a location of a stored playlist. The method also comprises obtaining from a server a playlist in response to a user input, where the playlist includes location information identifying a location of a stored transport stream. The method also comprises receiving the transport stream from the location identified in the playlist over a network, and displaying the obtained transport stream. | 7 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is based on and claims priority under 35 U.S.C. 119 from Japanese Patent Application No. 2006-308172 filed Nov. 14, 2007.
BACKGROUND
[0002] 1. Technical Field
[0003] This invention relates to a sheet waste processing device which is employed in an image forming apparatus such as a copying machine or printer, and more particularly to a sheet waste processing device having a sheet waste generating unit capable of generating sheet wastes and an image forming apparatus using it.
[0004] 2. Related Art
[0005] In recent years, with development of “on-demand publishing”, has been widely used the image forming apparatus such as an “in-line type” of copying machine or printer equipped with a center-binding function and a cutting function for making a booklet in addition to an image forming function.
[0006] Such an apparatus is provided with a cutting device serving as a sheet waste processing device in which the edges (e.g. cut ends) of a booklet are cutting-finished so as to be finely trimmed in order to complete the booklet. The sheet wastes generated by cutting are taken in a housing vessel within the cutting device and appropriately disposed of.
SUMMARY
[0007] According to an aspect of the present invention, a sheet waste processing device includes: a sheet processing tool that generates piece-like sheet wastes by processing for sheets; a waste receiver that is provided freely movably under the sheet processing tool between a setting position where the sheet wastes generated by the sheet processing tool are received and a non-setting position where the sheet wastes received are disposed of; and a transporting/guarding member that is provided between the sheet processing tool and the waste receiver, transports the sheet wastes into the waste receiver located at the setting position, and blocks direct touching the sheet processing tool from a waste receiver space.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] Exemplary embodiment of the present invention will be described in detail based on the following figures, wherein:
[0009] FIG. 1 is a view for explaining the schematic configuration of a sheet waste processing device according to this invention;
[0010] FIG. 2 is a view for explaining a printing device according to an embodiment to which this invention is applied;
[0011] FIG. 3 is a view for explaining a digital copying machine according to the embodiment;
[0012] FIGS. 4A and 4B are views for explaining a cutting device according to the embodiment;
[0013] FIG. 5 is a sectional view in FIG. 4A ;
[0014] FIGS. 6A to 6C are views for explaining transporting/guarding member according to the embodiment;
[0015] FIGS. 7A and 7B are views showing a housing tray according to the embodiment;
[0016] FIG. 8 is a view for explaining changes in a sheet bundle according to the embodiment; and
[0017] FIGS. 9A to 9C are views for explaining the manner of the sheet bundle on the housing tray according to the embodiment.
DETAILED DESCRIPTION
[0018] On the basis of an embodiment shown in the drawings attached herewith, a detailed explanation will be given of typical modes of this invention.
[0019] FIG. 2 shows a printing device serving as an image forming apparatus including a sheet waste processing device according to an embodiment to which this invention is applied.
[0020] In FIG. 2 , reference numeral 10 denotes a digital copying machine serving as the image forming apparatus. Images are formed on sheets by the digital copying machine 10 . The sheets with the images formed thereon are subjected to several kinds of processing. On the downstream side of the digital copying machine 10 , therefore, combined therewith is a post-processing device 70 which executes post-processing such as binding processing, hole-making (punching) processing and center-binding/center-folding for the sheets. Arranged between the digital copying machine 10 and the post-processing device 70 are an inverted-transporting device 50 for inverted-transporting the sheet and a sheet stand-by device 60 for causing sheets to stand by as the occasion demands.
[0021] Further, in this embodiment, arranged on the downstream side of the post-processing device 70 are a cutting device 100 for finish-cutting a bundle of sheets in a booklet form center-bound and center-folded by the post-processing device 70 and a housing tray 120 for housing the bundle of sheets (booklet) cut by the cutting device 100 .
[0022] The digital copying machine 10 in this embodiment is configured as shown in FIG. 3 . As seen from FIG. 3 , on its upper side, the digital copying machine 10 includes an image reading device 40 for reading the image of a document 42 set on a platen glass 41 . Beneath the image reading device 40 , an image forming unit is provided. The image forming unit creates a toner image on a photosensitive body 11 and transfers the toner image thus created onto a sheet S transported by feeding roll 25 from plural sheet-feeding cassettes 21 to 24 arranged below the image forming unit.
[0023] Therefore, arranged around the photosensitive body 11 are a charger 12 such a charging roll for uniformly charging the photosensitive body 11 , a light-exposing device 13 such as a laser scanner for forming a latent image on the photosensitive body 11 charged, a developing device 14 for visually imaging the latent image on the photosensitive body 11 , a transferring device 15 such as a colotron for transferring the toner image created on the photosensitive body 11 onto the sheet S fed from each of the feeding cassettes 21 to 24 and a cleaner 17 for cleaning the toners remaining on the photosensitive body 11 after transfer. Reference numeral 16 denotes an ionizer for separating the sheet S after the toner image is transferred from the photosensitive body 11 . Reference numeral 44 denotes an image information processing unit for processing the image information of the document 42 read by the image reading device 40 . Reference numeral 43 indicated in two-dot chain line denotes an automated document feeding device, which is an optional device, for feeding the document 42 onto the platen glass 41 .
[0024] Further, the sheet transporting system in this digital copying machine 10 is constructed as follows. In the vicinity of the sheet feeding cassettes 21 to 24 , feeding rolls 25 for feeding the sheet S from each of the feeding cassettes 21 to 24 are provided. The sheet S fed by the feeding rolls 25 is transported by transporting rolls 26 arranged as required and guided to resist rolls 27 on the upstream side of the photosensitive body 11 . The resist rolls 27 control the positioning of the sheet to transport, at a predetermined timing, the sheet to an area where the photosensitive body 11 and the transferring device 15 are opposite to each other.
[0025] The sheet subjected to transfer is transported to a fixer 28 in which the non-fixed toners on the sheet are fixed by e.g. heating and pressurizing. The sheet subjected to fixing is guided from exit roll 29 of the fixer 28 to ejecting roll 30 and transported to the device on the downstream side (inverted-transporting device 50 in this embodiment).
[0026] On the other hand, where images are to be created on both sides of the sheet, the sheet passed the exit roll 29 of the fixer 28 is changed downward in its transporting direction by an inverting gate 31 and guided to an inverted-transporting path 34 through a tri-roll 32 composed of three roles arranged in pressure-contact and inverting rolls 33 . The sheet reached the inverted-transporting path 34 is transported to a return transporting path 36 with transporting rolls 35 by the inverting operation of the inverting rolls 33 under the condition that the rear end of the sheet is sandwiched by the inverting rolls 33 . The sheet transported to the return transporting path 36 is given an image on the rear surface by the charge transfer 15 via the resist rolls 27 and thereafter subjected to fixing by the fuser 28 . The sheet subjected to the fixing is transported to the device on the downstream side via the exit roll 29 and ejecting roll 30 .
[0027] In this way, the sheet with the image created by the digital copying machine 10 , as shown in FIG. 2 , is guided by the inverted-transporting device 50 or the sheet stand-by device 60 so that it is inverted-ejected to an ejecting tray 51 provided above or transported to the succeeding post-processing device at a predetermined timing by the sheet stand-by device 60 .
[0028] The post-processing device 70 in this embodiment is provided with transporting rolls 71 for transporting the sheet fed from the sheet stand-by device 60 at the inlet and a puncher 72 for punching located immediately behind it. On the downstream side of the puncher 72 , the sheet transporting path is branched. An upper sheet transporting path 73 is further branched into a sheet transporting path 74 along which the sheet, as it is, guided to an ejecting tray 76 provided above the post-processing device 70 and a sheet transporting path 75 along which the sheet after edge-bound is ejected to an offset catch tray 77 . Therefore, the sheet transporting paths 73 , 74 and 75 are appropriately provided with transporting rolls for sheet transportation and sensors, respectively.
[0029] Further, the sheets transported to the sheet transporting path 75 are lined up by a paddle 81 and a tamper 82 and thereafter bound in their sheet edges by a stapler 83 and ejected onto the offset catch tray 77 . The offset catch tray 77 is adapted to automatically move downward as the number of the bundles of sheets increases.
[0030] On the other hand, a sheet transporting path 78 branched downward from the puncher 72 is provided with a center-binding processing device 90 for making a booklet composed of plural sheets.
[0031] The center-binding processing device 90 is provided with a sheet aligning tray 92 slanted on the skew. On the upstream side thereof, paddle-equipped transporting rolls 91 located for transporting the sheet to the sheet aligning tray 92 is located. At the lower end of the sheet aligning tray 92 , an end guide 96 for positioning the lower end (tip) of the sheet at a predetermined position is provided so that it can move along the vertical direction of the sheet aligning tray 92 . Further, in the vicinity of the end guide 96 , a paddle 97 for aligning the lower ends of the sheets is provided.
[0032] Further, at the upper end of the sheet aligning tray 92 , a damper (not shown) for aligning the ends in the width direction of the sheets arranged on the sheet aligning tray 92 is provided. A damper driving unit 98 for driving the damper is provided.
[0033] Thus, the sheets transported from the sheet transporting path 78 to the center-binding processing device 90 are aligned every plural sheets by the sheet aligning tray 92 via the paddle-equipped transporting roll 91 .
[0034] Further, the center binding processing device 90 is also provided with a center-binding saddle stapler 94 for center-binding a bundle of plural sheets lined up on the sheet aligning tray 92 . Above the saddle stapler 94 , a knife wedge 95 for center-folding the bundle of the plural sheets center-bound is movably provided oppositely to a pair of center-folding roll 93 . Thus, by moving the end guide 96 , the plural sheets lined up on the sheet aligning tray 92 are center-bound by the saddle stapler 94 . By moving the knife wedge 95 toward the pair of the center-binding rolls 93 , the sheet bundle center-folded is transported with the center fold being at the head from an ejecting roll 99 to the succeeding cutting device 100 .
[0035] Further, in this embodiment, between the cutting device 100 and the post-processing device 70 , belt transporters 107 circulating in a pair configuration are provided. The sheet bundle created as the booklet by the post processing device 70 is sandwich-transported by the belt transporter 107 and thereafter guided to a device body 101 of the cutting device 100 . Within the device body 101 of the cutting device 100 , transporting belts 102 , 103 in the pair configuration for the sandwich-transporting the sheet bundle in the booklet form are provided as e.g. two sets of parallel belts in a direction nearly perpendicular to the transporting direction. Between the belts, a stopper 104 for positioning the tip (center fold of the booklet) is provided. The stopper 104 can advance or retreat, for example, from below for the sheet bundle transporting plane.
[0036] Therefore, after the sheet bundle in the booklet form which being sandwiched by the transporting belts 102 , 103 is positioned by the stopper 104 , it is cutting-finished in its rear end in such a manner that a knife 105 serving as a sheet processing tool located on the upstream side of the stopper 104 descends.
[0037] In this case, the sheet wastes generated owing to cutting by the knife 105 are housed in a waste receiving box 106 which is a waste receiver mountably provided within the device body 101 . The shape and others of the waste receiving box 106 are not particularly limited as long as it can receive the sheet wastes. For example, the waste receiver may be a vessel with rigidity or a vessel using a film-like sack.
[0038] In particular, the cutting device 100 in this embodiment is structured as shown in FIGS. 4A and 4B . Now, FIG. 4A shows a stage in which the waste receiving box 106 is mounted at a setting position within the device body 101 . FIG. 4B is a stage in which the waste receiving box 106 has been removed from the device body 101 (moved at a non-setting position). FIG. 5 is a view seen from the direction of an arrow A in FIGS. 4A and 4B . FIG. 5 shows the cutting device 100 in an intermediate stage between FIGS. 4A and 4B , i.e. the intermediate stage in the process in the waste housing 106 is removed from the device body 101 (the stage moving from the setting position).
[0039] Within the device body 101 of the cutting device 100 in this embodiment, an inlet roll 108 is provided where the sheet bundle in the booklet form transported from the post processing device 70 side is transported into the device body 101 . Between the inlet roll 108 and the knife 105 , guide members 109 , 110 for guiding the sheet wastes generated owing to cutting by the knife 105 to the waste receiving box 106 are provided. Further, below the guides 109 , 110 , a pair of rolling members 111 for transporting the sheet wastes guided by the guides 109 , 110 to the sheet waste transporting box 106 are provided so as to roll in directions of arrows. The rolling members 111 serve as a transporting/guarding member in this embodiment.
[0040] Further, the waste receiving box 106 is provided so that it can be pulled out from a receiver 106 a within the device body 101 (for example, in FIG. 4A , pulled out toward this side of the figure). Particularly, in this embodiment, on the lower side of the receiver 106 a , i.e. on the bottom side of the waste receiving box 106 , a concave area 106 b is formed so that when the waste receiving box 106 is mounted in the receiver 106 a (at a setting position), a space is kept between the receiver 106 a and the waste receiving box 106 .
[0041] FIG. 5 is a sectional view when seen from the side in FIG. 4A . The sheet wastes generated owing to cutting by the knife 105 are housed, as they are, into the waste receiving box 106 through the rolling members 111 .
[0042] As for the rolling members 111 in this embodiment, as seen from FIG. 6A , two members 111 a , 111 b are arranged apart from each other by a predetermined gap. This gap d is kept with a narrow gap so that from the space side when the waste receiving box 106 at the setting position is moved, an operator's finger does not touch the knife 105 . Namely, the rolling members 111 have also a guarding function. Thus, in this embodiment, the pair of rolling members 111 serve as transporting/guarding member.
[0043] In this embodiment, by arranging the rolling members 111 in this way, there can be provided a cutting device 100 in which the sheet wastes are preferably transported, invasion of the operator's finder can be prevented, and safety is also considered.
[0044] Further, as seen from FIG. 2 , on the downstream side of the cutting device 100 , a housing tray 120 for housing sheet bundles in the booklet form cutting-finished is provided so as to project nearly horizontally from the one side of the cutting device 100 .
[0045] In the housing tray 120 , as shown in FIGS. 7A and 7B , two sheet bundle transporting belts 122 ( 122 a , 122 b ) rotatably for a supporting frame 121 are arranged in nearly parallel so as to constitute a transporting plane (along which the sheet bundle in the booklet form is transported) projecting upward from the supporting frame 121 . At the tip side (downstream side in the transporting direction) of the supporting frame 121 , a slope 123 is provided which projects in a rearward sloped state from the supporting frame 121 . At the slope 123 , the sheet bundle transported by the sheet bundle transporting belts 122 is stopped and stacked thereon. Further, in the vicinity of the end on the downstream side of the sheet bundle transporting belts 122 at the upper position of the supporting frame 121 , a full stack sensor 125 is provided for detecting the fully stacked state of the sheet bundles stacked and housed by the slope 123 . Furthermore, as shown in FIG. 2 , above the sheet bundle transporting belts 122 , a depressing member 124 is provided for depressing the sheet bundle transported on the sheet transporting belts 122 .
[0046] In this embodiment, the sheet transporting belts 122 of the housing tray 120 are drive-controlled so that the sheets bundles ejected onto the sheet bundle transporting belts 122 from the cutting device 100 are successively stacked.
[0047] An explanation will be given of the operation of the printing device having the structure as described above, mainly of the processed state of the sheets after the post-processing device 70 .
[0048] In this embodiment, as shown in FIG. 2 , the sheet with the image created by the digital copying machine 10 is transported to the post-processing device 70 via the inverted-transporting device 50 and sheet stand-by device 60 . The sheet passed through the sheet transporting path 78 of the post-processing device 70 is transported to a center-binding device 90 . The bundle of sheets lined up is center-bound and center-folded. The sheet bundle folded is transported with the fold being at the head from the ejecting roll 99 to the succeeding cutting device 100 via the belt transporting body 107 .
[0049] In the cutting device 100 , with the fold of the sheet bundle being positioned by the stopper 104 , the sheet bundle is cut by the knife 105 so that it is cutting-finished (cut-end finished) to have a predetermined length.
[0050] The sheets in such a process until the cutting change as shown in FIGS. 8A to 8C . Specifically, as shown in FIG. 8A , the plural sheets lined up become the sheet bundle center-bound in the post-processing device 70 . The sheet bundle center-folded within the same post-processing device 70 becomes the shape as shown in FIG. 8B . At this time, the length of the sheet bundle folded is different between its internal side and the external side (surface side). So, the lengths at the end of the sheet bundle at the center-folded stage are not uniform. By cutting-finishing the non-uniform portion using the cutting device 100 , the finished state with the lengths at the end aligned can be obtained as shown in FIG. 8C .
[0051] The sheet bundles cutting-finished by the cutting device 100 are successively ejected to the housing tray 120 . In this case, since the sheet bundle transporting belts 122 of the housing tray 120 are drive-controlled so as to move at a predetermined timing, the sheet bundles on the sheet bundle transporting belts 122 are ejected so that a succeeding sheet bundle is stacked on at a part of the sheet bundle earlier ejected. The sheet bundles stacked are successively transported toward the slope 123 by the transporting force of the sheet bundle transporting belts 122 . The sheet bundles are successively dammed by the slope 123 so that the succeeding sheet bundles are stacked in their raised state. When the sheet bundles exceed the full stack sensor 125 , housing of the sheet bundles into the housing tray 120 is stopped.
[0052] FIGS. 9A to 9C show the stacked state of the sheet bundles in the housing tray 120 . As shown in FIG. 9A , as regards the sheet bundles on the housing tray 120 , the succeeding sheet bundle is partially stacked on the preceding sheet bundle. The sheet bundles successively stacked, as they are, are transported toward the slope 123 within the housing tray 120 . When the sheet bundle at the head reaches the slope 123 , since the slope 123 is angled at a predetermined angle, the sheet bundle suffers the transporting force given by the sheet bundle transporting belts 122 and friction force at the area where the sheet bundle itself come in contact with. Thus, the sheet bundles slide on the slope 123 and are lined up with their fold oriented upward. The succeeding sheet bundle is also influenced by the preceding sheet bundle so that the sheet bundles are lined up in a direction standing with their fold oriented upward. Thus, the sheet bundles successively lined up as shown from FIG. 9B to FIG. 9C . When it is detected by the full stack sensor 125 (see FIG. 7 ) that the sheet bundles are fully stacked on the housing tray 120 , a message display may be made by, for example, an operation unit of the digital copying machine 10 so that an operator is urged to take out the sheet bundles lined up from the housing tray 120 .
[0053] On the other hand, the sheet wastes generated owing to cutting by the cutting device 100 , as shown in FIG. 4A , are downward transported by the rotating force of the rolling members 111 from the guides 109 , 110 through between the pair of rolling members 111 (concretely, 111 a and 111 b in FIG. 6 and housed into the waste receiving box 106 .
[0054] At this time, since the rolling members 111 are rotating, the sheet wastes can be preferably transported.
[0055] The rotation of the rolling members 111 may be stopped, for example, at the stage when the waste receiving box 106 has been moved from the receiver 106 a within the device body 101 of the cutting device 100 . However, in this embodiment, also when the waste receiving box 106 has moved, the rolling members 111 continue to rotate, as they are, so that the sheet wastes can be housed in the concave area 106 b formed below the waste receiving box 106 . For this reason, also in disposing of the sheet wastes in the waste receiving box 106 , it is not necessary to stop the operation of the cutting device 100 , thereby restraining degradation in the productivity of the cutting device 100 . The concave area 106 b may be cleaned by in the manner of, for example, scratching out the sheet wastes housed in the concave area 106 b with a hand. Even if such a manner is adopted, since safety is assured, a particularly problematic situation does not occur.
[0056] In this embodiment, the gap d (see FIG. 6A ) between the pair of rolling members 111 was fixed using the pair of rolling members 111 serving as the transporting/guarding member (concretely, 111 a , 111 b ). However, for example, at the stage when the waste receiving box 106 is mounted, a gap wider than this gap d may be given. Further, when the waste receiving box 106 has been moved from the receiver 106 a , the gap d may be lost (the rolling members 111 are brought into contact with each other). Furthermore, the rolling members 111 may be brought into contact with each other from the beginning as long as the sheet wastes are transported.
[0057] Further, a guide may be located at the position opposite to a single rolling member 111 adopted as the transporting/guarding member so that the space between the single rolling member 111 and the guide serves as a route for transporting the sheet wastes. In this case, as the guide, a dedicated guide may be provided, or otherwise, for example, a frame of the device body 101 may be used.
[0058] In this embodiment, the pair of rolling members 111 as shown in FIG. 6A were employed as the transporting/guarding member. However, the members as shown in FIG. 6B or 6 C may be employed.
[0059] The transporting/guarding member shown in FIG. 6B is a pair of rotating members 112 ( 112 a , 112 b ) each with a plural projections 113 ( 113 a , 113 b ) formed on the surface. By using these rotating members 112 , the space between the projections 113 can be lost, and while the sheet wastes are transported, these projections 113 can improve the transportability, thereby providing the transporting/guarding member in which the transportability of the sheet wastes and the safety are taken into consideration. In this case, the material of the projections 113 should not be limited, but is preferably rubber with high hardness according to the deformation of the sheet wastes and from the viewpoint of safety.
[0060] Further, the rotating members 112 may be formed in either a roll-shape or belt-shape. Moreover, the pair of rotating members 112 is provided so that they can be brought into contact with or separation from each other. Particularly, if the rotating members 112 are adapted to be brought into contact with each other, the guarding function by the transporting/guarding member can be further enhanced. Furthermore, the rotating members 112 provided with the projections may be realized, for example, in such a manner that the projections are formed on the surface of the rolling member or belt member, or a paddle-like manner.
[0061] Further, the transporting/guarding member shown in FIG. 6C is composed of a pair of belt members 114 ( 114 a , 114 b ) with a plural projections 115 ( 115 a , 115 b ) formed on the surface. Using these belt members 114 , the same advantage as in FIG. 6B can be obtained.
[0062] As understood from the description hitherto made, in this embodiment, upon housing the sheet wastes generated in the cutting device 100 to the waste receiving box 106 , since the transporting/guarding member is provided between the knife 105 and the waste receiving box 106 , both functions of the transportability of the sheet wastes and the safety can be satisfied.
[0063] Additionally, such application of the transporting/guarding member to the cutting device 100 means that they can be also applied to the manner of sheet processing in e.g. a puncher or stapler. In such a case also, the transporting/guarding member may be employed.
[0064] Further, in this embodiment, the digital copying machine 10 was employed as the image forming unit. Without being limited to it, a printer may be employed. In this embodiment, although a monochromatic image was created by the digital copying machine 10 , it is needless to say that a color image may be created.
[0065] The foregoing description of the embodiments of the present invention has been provided for the purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise forms disclosed. Obviously, many modifications and variations will be apparent to practitioners skilled in the art. The embodiments were chosen and described in order to best explain the principles of the invention and its practical applications, thereby enabling others skilled in the art to understand the invention for various embodiments and with the various modifications as are suited to the particular use contemplated. It is intended that the scope of the invention defined by the following claims and their equivalents. | A sheet waste processing device includes: a sheet processing tool that generates piece-like sheet wastes by processing for sheets; a waste receiver that is provided freely movably under the sheet processing tool between a setting position where the sheet wastes generated by the sheet processing tool are housed and a non-setting position where the sheet wastes housed are disposed of; and a transporting/guarding member that is provided between the sheet processing tool and the waste receiver, transports the sheet wastes into the waste receiver located at the setting position, and blocks direct touching the sheet processing tool from a waste receiver space generated by movement of the waste receiver under the condition that the waste receiver is moved to the non-setting position. | 1 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates generally to measurement, communication, and performance-monitoring apparatus used in the installation and operation of geothermal well power systems of the kind providing for the generation of electrical power by utilizing energy from subterranean geothermal sources and, more particularly, relates to arrangements for monitoring the operation of such geothermal power systems including efficient super-heated vapor generation and pumping equipment for application within deep hot water wells for the beneficial transfer of thermal energy to the earth's surface.
2. Description of the Prior Art
The present invention is designed for use in operating geothermal well power generation systems of the general kind further discussed herein, for example, that abstract thermal energy stored in hot solute-bearing well water to generate vapor, preferably superheated, from an injected flow of clean liquid; the superheated vapor is then used in operating a turbine-driven pump at the well bottom, pumping the hot-solute bearing water at high pressure and in liquid state to the earth's surface to effect transfer of its heat content to a closed-loop boiler-turbine-alternator combination for the generation of electrical power. Cooled, clean fluid is regenerated by the surface-located system for reinjection into the deep well and the solute-bearing water is pumped back into the earth.
Geothermal wells may be logged to a useful extent by methods applied previously in the oil well industry. In such tests, a canister which may contain sensors, a battery, and a recorder is lowered into the well and is then brought back to the earth's surface where the recorded data is retrieved. This time-consuming method is undesirable even in the oil well application, as it is not a real-time method and requires removal of pumping equipment from the well. Where an operating system such as a geothermal well pump is present, removal of the pump system cannot be considered on economic grounds and only secondary ways of finding out qualitatively what is occurring at the deep well pump site are available.
One prior art permanent monitoring method which has achieved significant success in geothermal well installations is taught in the H. B. Matthews U.S. Pat. No. 3,988,896, issued Nov. 2, 1976 for a "Geothermal Energy Pump and Monitor System" and assigned to Sperry Rand Corporation. Continuous monitoring of various parameters of the deep well system is permitted, including well water pressure and temperature immediately below the pump, the pressure increment across the pump, and the rotational speed of the pump, for example. Means are provided at the deep well pump location for generating electrical signals representative of well water pressure below and above the pump, of well water temperature below the pump, and of the rotational speed of the geothermal pump, these data being communicated to receiver and utilization means disposed at the earth's surface. A permanent magnet generator system supplies the signal representative of pump rotation speed, also providing electrical energy for the multiplexing and communication of the multiplexed signals. Conventional sensors may be employed, or improved bridge sensors such as disclosed by K. W. Robbins and G. F. Ross in the U.S. patent application Ser. No. 810,220, for a "Geothermal Well Pump Performance Sensing System and Monitor Therefor", filed June 27, 1977, issued Aug. 22, 1978 as U.S. Pat. No. 4,107,987 and assigned to Sperry Rand Corporation.
It will be understood by those skilled in the geothermal power generation art that a wide range of characteristics must be faced by the designer who approaches the geothermal well monitoring problem. Each well has its own particular characteristics and the design of its pumping system and its monitor must be compatible with such characteristics. In some circumstances, it is impossible or at least not convenient to use the down-well generator of the aforementioned U.S. Pat. No. 3,988,896 on the basis of space considerations. In other wells, where high-speed down-well systems are dictated, conditions are such that the balanced condition of the electrical generator may not survive for a reasonable life time.
SUMMARY OF THE INVENTION
The present invention relates to telemetric apparatus for monitoring, whether in operation or standby, the parameters associated with deep well geothermal pumps. Sensors at the deep well pump site detect magnitudes, for example, of well water temperature and pressure immediately below and above the pump and this data is transmitted by multiplex communication via a novel two-wire telemetric system to a receiver for use at the earth's surface. All power for excitation of the deep well monitor units is supplied from the earth's surface over the same two-wire data link, thus eliminating the need for generation of considerable electrical power at the down-well pump location. A novel cylindrically symmetric, mechanically separable transformer is connected in effect in series in the two-wire line system within a conduit system providing lubricant to the bearings of the turbine-motor-pump unit. The transformer configuration aids in the ready installation of the deep well pump system, and its removal from the well in the event that such a requirement arises, by eliminating the multitude of electrical connections required by an integrally wired down-well measurement and telemetry system.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an elevation view, mostly in cross-section, of a deep well geothermal pump showing the general disposition of the novel monitor system.
FIG. 2 is a cross-section of the instrumentation system of FIG. 1 on a somewhat larger scale and in greater detail.
FIGS. 3 and 4 are cross-section views of the novel separable transformer 102, 103 of FIG. 2.
FIG. 5 is a wiring diagram showing electrical features of the apparatus of FIGS. 1 and 2 and illustrating component circuits and their interconnections.
FIG. 5A is a diagram of an alternative form of the transformer shown in FIG. 5.
FIG. 6 is an elevation view in partial cross-section, useful in discussing the method of installation of the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 illustrates the general structural characteristics of that portion of one type of geothermal energy extraction system which is immersed in a deep well extending into strata far below the surface of the earth, preferably being located at a depth such that a copious supply of extremely hot geothermal water under high pressure is naturally available, the active pumping structure being located adjacent the water source and within a generally conventional well casing pipe 25. The configuration in FIG. 1 is seen to include a well head section 20 normally located above the earth's surface 31 and a main well section 49 extending downward from well head section 20 and below the earth's surface 31. At the subterranean source of hot, high pressure water, the main well section 49 joins a vapor generator section 63. The vapor generator section 63, the vapor motor turbine section 70, a rotary bearing section 71, and a hot water pumping section 72 follow in close cooperative succession at increasing depths. Interposed between the vapor generator section 63 and the vapor motor turbine section 70 is a section including measurement and communication elements for facilitating the monitoring function performed according to the present invention, a section identified as the instrumentation section 65, yet to be described in detail with the aid of FIGS. 2 through 5.
Extending downward from the well head section 20 at the earth's surface 31, the well casing pipe 25 surrounds in preferably concentric relation an innermost stainless steel or other high quality alloy steel pipe 17 for supplying relatively pure water under pressure from the earth's surface 31 at the bottom of the geothermal well, as indicated by arrow 15 and as will be further explained. A second relatively larger pipe 27 surrounding pipe 17 forms a conduit 21 within well casing 25, extending from well head 20 to the energy conversion and pumping system at the bottom of the well and permitting turbine exhaust vapor to flow upward to the surface of the earth as indicated by arrow 34.
It will also be understood from FIG. 1 that relatively clean and cold liquid, reformed at the earth's surface by condensing the vapor stream flowing up conduit 21 and the branching exit pipe 19, is reinjected by a second branching input pipe 18 into conduit 24 defined by the concentric pipes 23 and 27. This liquid flows downward as a working fluid in conduit 24 as indicated by arrow 35 to be converted into high pressure vapor for driving the vapor turbine of turbine section 70. The liquid employed may be pure water or a suitable organic fluid.
The function of the turbine located at section 70 and supported by shaft 66, 73 and bearings 67, 68 and 69 located within bearing section 71 is to drive a hot well water pump located at section 72. Hot, high pressure water or brine is thus impelled upwardly by the rotating pump vanes 74 between the rotating conical end of the pump and the associated stationary shroud 75. The hot water is pumped upward at a high velocity in annular conduit 26 between pipes 23 and 25, thus permitting use, for example, of the thermal energy it contains at the earth's surface by a power plant coupled to pipe 32. More important, the hot well water is pumped upward to the earth's surface 31 at a pressure preventing it from flashing into steam and thus undesirably depositing dissolved salts at any such point of flashing.
Accordingly, it is seen that the extremely hot, high-pressure geothermal well water is pumped upward, flowing in the annular conduit 26 defined by alloy pipes 23 and 25. Heat supplied by the hot well water readily converts the clean water flowing from conduit 24 into the steam generator at section 63 into highly energetic, dry, superheated steam. The clean water in conduit 24 is maintained at a very high pressure due to its hydrostatic head and to pressure added by a surface pump (not shown) so that it may not flash into steam. The highly energetic steam drives the steam turbine and shaft 66 and is redirected to flow upward to the earth's surface 31 after expansion as relatively cool steam flowing within the annular conduit 21 defined between alloy pipes 17 and 27. Thermal energy is recovered at the earth's surface 31 primarily from the hot, high pressure well water, but may also be retrieved from the turbine exhaust steam.
The elements of the FIG. 1 apparatus so far considered, with the exception of instrumentation section 65, are substantially similar to those of the following United States Patents assigned to Sperry Rand Corporation:
H. B. Matthews U.S. Pat. No. 3,824,793, issued July 23, 1974 for "Geothermal Energy System and Method",
H. B. Matthews U.S. Pat. No. 3,898,020, issued Aug. 5, 1975 for "Geothermal Energy System and Method",
H. B. Matthews U.S. Pat. No. 3,938,334, issued Feb. 17, 1976 for "Improved Geothermal Energy Control System and Method",
H. B. Matthews, K. E. Nichols U.S. Pat. No. 3,910,050, issued Oct. 7, 1975 for "Geothermal Energy System and Control Apparatus",
J. L. Lobach U.S. Pat. No. 3,908,380, issued Sept. 30, 1975 for "Geothermal Energy Turbine and Well System", and
R. Govindarajan, J. L. Lobach and K. E. Nichols U.S. Pat. No. 3,905,196, issued Sept. 16, 1975 for "Geothermal Energy Pump Thrust Balance Apparatus".
The invention is found equally suitable for application in a second type of geothermal energy extraction system of the type disclosed by H. B. Matthews in the U.S. patent application Ser. No. 860,270 for a "Geothermal Energy Conversion System", filed Dec. 13, 1977, issued Feb. 27, 1979 as U.S. Pat. No. 4,142,108 and also assigned to Sperry Rand Corporation. The latter system is a geothermal energy recovery system of reduced cost and improved efficiency that makes use of thermal energy stored in hot, solute-bearing well water during the period that it is pumped upward to the earth's surface through an extended lineal heat exchange element for continuously heating a downward flowing organic working fluid. The added energy of the latter fluid is then used within the well for operating a turbine-driven pump for pumping the hot, solute-bearing well water at high pressure and always in liquid state to the earth's surface, where it is reinjected into the earth by a sump well. The temperature difference between the upward flowing brine and the downward flowing organic working fluid is maintained finite in a predetermined manner along the length of the subterranean extended heat exchange element. After driving the deep well turbine-driven pump, the organic fluid arises to the earth's surface in a thermally insulated conduit; at the earth's surface, electrical power generation equipment is driven by the ascending organic fluid, after which it is returned into the well for reheating in a closed loop as it travels downward in the extended heat exchanger.
According to the present invention, the brine pump input pressure is measured by a conventional pressure sensor 77 located below the input shroud 75 of the geothermal pump, preferably at a location sufficiently below shroud 75 to avoid flow disturbances induced by operation of the pump. The measured pressure signals are preferably electrical signals conveyed by conductors in a corrosion immune tube 76 into the instrumentation section 65. Tube 76 or other conventional support elements may be mechanically sufficient to support pressure sensor 77, as well as an associated conventional temperature sensor 78, from which further electrical signals are supplied in a similar manner within instrumentation section 65. A further conventional pressure sensor 64 is mounted on pipe 23 and is used to provide electrical signals within instrumentation section 65 representing the magnitude of the pressure of the pumped well water between pipes 23 and 25 at a convenient location above the exhaust of pump section 72. Further signals representative of the rate of rotation of the pump shaft 66 and therefore of the turbine and geothermal fluid pump may be generated by a simple tachometer (not shown) of the type in which the pole of a magnet mounted somewhere on the rotating pump exterior structure passes a fixed coil once each revolution of shaft 66. Since the tachometer generator need generate only a low power level signal, the expense and design problems attendant a large power generator driven by shaft 66 are avoided. A simple configuration immune to the rigorous down-well conditions will easily be envisioned by those skilled in the art.
The two pressure representative signals, the temperature signal, and shaft speed or other signal are processed in a manner to be described with reference to FIG. 5 within the instrumentation section 65 wherein multiplexed signals are generated for propagation toward the earth's surface 31. Electric signals may thus be received at the earth's surface 31 for use in apparatus for display, recording, or control purposes.
The instrument section 65 is the major locus of the novel apparatus of the present invention; it is shown in greater detail in FIG. 2. As in FIG. 1, the instrumentation section 65 is located adjacent the deep well pump within the concentrically disposed pipes 27 and 23 and the outer well casing 25. More particularly, the principal elements of the instrumentation apparatus are supported axially within conduit 21 and are cooled within the rising and expanding vapor stream 34 as it is exhausted by the turbine of turbine section 70 of FIG. 1.
One function of the invention is to provide electrical connections to and from surface-located test equipment, as will be more particularly described in connection with FIGS. 5 and 6, and measurement apparatus permanently disposed in the instrumentation system 65. For this purpose, a hollow pipe 17, suspended from the well head plate 20, extends downward in the well to section 65. At the latter location, pipe 17 is expanded by the conical adapter 100 to support a larger diameter shell envelope 101 closed at its bottom end by end plate 120 welded to shell 101 so as to define a generally cylindric internal cavity 108. End plate 120 centrally supports a reentrant portion 107 equipped with a bore that is internally threaded. An upper threaded part of the bore cooperates with a threaded pipe 104 whose bore 105 extends upward into electrical transformer element 103.
Elements 102 and 103 cooperatively form separable windings of an electrical transformer, the lower element 103 thereof being supported on pipe 104, while the upper element thereof is supported by the downwardly extending tube 14. Tube 14 is concentric within pipe 17 and, like pipe 17, is normally supported at the well head 20. The internal diameter of pipe 17 is made slightly greater than the maximum outer diameter of transformer element 102 so that the latter may be lowered from the top of the well to the normal operating position shown in FIG. 2. Stainless steel tube 14 acts as a protective envelope for electrical leads 16, which may be supplied with suitable electrical insulating covers.
Just as the leads 16 couple to the winding of transformer element 102, at least a pair of electrical leads (not shown in FIG. 2) extend from the second transformer element 103 through bore 105, reentrant portion 107, and a bore in pipe 121 into the closed electronic circuit envelope 124. Cavity 108 also acts as a cavity reservoir for containing lubricating fluid under pressure for supply via tubes 106 and 123 to the turbine motor-pump bearings 67, 68, 69 (FIG. 1) in the manner indicated in the aforementioned U.S. Pat. No. 3,988,896. The bearings 67, 68, 69 are of a conventional nature with seals such that the lubricant fluid cannot leak out of the bearing system in any substantial amount; therefore, a large volume flow of lubricant into the bearings is not needed and the single space-saving small supply tube 123 is used to supply an adequate amount of lubricant for bearings 67, 68, 69. A bearing system with seals of the kind shown in the aforementioned patent application Ser. No. 860,270, may be employed in the present invention, for example.
The lubricant cavity 108 and the lower transformer element 103 are supported by the axially disposed pipe 121 at the top of electronic circuit envelope 124, the location of envelope 124 being determined by a plurality of radially disposed vanes such as vanes 125, 126 welded to envelope 124 and to the opposite inner wall of pipe 27. Vanes 125, 126 tend to augment the cooling of envelope 124 and its contents by the action of expanding vapor flowing in conduit 21 in the sense of arrow 34 away from the turbine motor located just below envelope 124. Between the bottom of transformer 102, 103 and the upper end of circuit envelope 124 is located a horizontal screen 119 adapted to collect debris which may fall into conduit 21 and which would otherwise damage or even destroy the turbine motor. Loose objects accidentally falling during installation of the apparatus are the objects of primary interest. FIG. 2 illustrates an electrical lead protecting tube 122 extending in sealed relation from electronic circuit envelope 124 through pipes 27 and 23 to sensor 64; it also again illustrates the electrical lead-protecting tube 76 also extending in sealed relation from the electronic circuit envelope 124 through pipes 27 and 23 downward to sensors 77,78.
It is seen that, according to the invention, electrical power is always available at the location in the well of the instrumentation section 65, independent of the presence of a power source deep in the well, such as a generator driven by shaft 66. Thus, continuous monitoring of the condition of the well is afforded, whether or not the pump 72 is operating. The electrical leads 16 from the earth's surface to the instrumentation section 65 do not normally need to be removed except in the unusual situation in which the entire turbine motor and pumping apparatus is to be removed from the well.
As illustrated in FIG. 3, the upper or movable transformer element 102 of FIG. 2 is the terminus of leads 16 which extend downward from the earth's surface 31 through the supporting protective tube 14. As will be seen, the interiors of stainless steel tube 14 and transformer element 102 are normally supplied with a stable gas under sufficient pressure (FIG. 6) to prevent lubricant or other fluids from destructively leaking into these parts. The device of FIG. 3 consists of a cylindrical magnetic core having an enlarged end portion 165 with a generally conically shaped tip 167. The core 164 extends upward to a fastener portion 154 which is threaded at 152 and is supported by matching threads from coupler 151. Coupler 151 is, in turn, equipped with outer threads 150 which are used to fasten the assembly to the bottom threaded end of tube 14. A cylindric protective shell envelope 162 is welded at its ends 159 and 166 to core 164, forming an annular cavity within which is first wound the coil winding 163. The leads 16 pass through branching bores 160, 161 in the upper or fastener portion 153 of the core to join the opposite ends of the electrical conductor making up coil 163. Core 164 and its parts 151, 165, and 167 are composed of a conventional high permeability magnetic material such as an electrical nickel steel or an iron-chromium or other similar magnetic alloy of which many types are readily available on the market.
The lower or fixed transformer element 103 from which electrical leads 208 originate is shown in detail in FIG. 4. It is generated around an interior cylindric shell 193 whose inside diameter is just slightly greater than the outside diameter of the exterior shell 162 of the apparatus of FIG. 3 so that the upper transformer element 102 may readily be lowered into the interior of cavity 191 of shell 193. Surrounding shell 193 is an outer magnetic cylindrical element 190 welded to shell 193 at 192. At the lower end of cylinder 190, it is welded at 200 to an annular end plate 201 of magnetic material. Plate 201 is centrally apertured so as to accommodate the axially disposed element 104 which has a reentrant portion extending into cavity 191. Element 104 is welded within annulus 201 at 202. The hollow shells 195, 193 and reentrant element 104 are again selected from machinable magnetic materials such as the iron-nickel or chromium types. In this manner, they form a part of the magnetic circuit necessary for true transformer operation, a suitable winding 194 or windings being wound in the cylindrical cavity formed between shells 193 and 190. An external axial extension of element 104 provides mechanical coupling to the base 120 of the lubricant reservoir envelope 101, 120, 121. Further, bores 203, 204, 105 in element 104 permit electrical leads 208 to be coupled between the ends of transformer winding 194 and the instrumentation case 124. The extension 104 is provided with a threaded portion 207 matching interior threads of reentrant part 107 of FIG. 2.
In order to complete the axially symmetric magnetic circuit to be formed by magnetic elements of transformer elements 102 and 103, it has been noted that element 102 is normally inserted within cavity 191 of element 103. For perfecting the magnetic circuit, it is to be noted that the axial core part 164 of device 102 has a generally conical tip 167 at its bottom. The surface of core 167 is generally conformal with a concave conical surface 196 formed in the upper interior end of part 104 of device 103. When element 102 has descended to its normal operating location within element 103, the two conical surfaces are in contact, efficiently completing the magnetic flux path with a gap of minimum thickness. In this manner, the magnetic flux passes, for example, through the inner core 164, the reentrant part of element 104, annulus 201, outer cylinder 190, and back into the top of inner core 164, thereby intercoupling transformer windings 163 and 194.
To aid descent of transformer portion 102 into the cavity 191 of the fixed transformer portion 103, any fluid or foreign matter present in cavity 191 must find ready egress. Such is effected by the branching bores 205, 206 which communicate at the vertex of conical surface 196 with the reservoir 108. Thus, any lubricant, which may be water, and small particulate matter, trapped within cavity 191 as the inner transformer part 102 enters cavity 191, is flushed out of the latter cavity via bores 205, 206 into reservoir 108. It will be understood that the two bores 205, 206 will preferably find themselves in a plane disposed at ninety angular degrees to the plane occupied by the branching bores 203, 204.
FIG. 6 illustrates apparatus used during the final installation of the stainless steel tube 14 and its contained pair of leads 16; the figure shows the movable transformer portion 102 suspended just above the opening into the fixed transformer portion 103. Above the well head plate 20, a branching pipe 289 is coupled to a source (not shown) of a lubricant fluid such as water or an organic liquid under pressure as indicated by arrow 290. Also above the well head plate 20 is a tube branching at tee 286 from the vertical tube 14 and containing a valve 287 for admitting a gas under pressure within tube 14. With transformer portion 102 lowered into its operating position within portion 103 after all of the pump and piping structure is in place and the well is sealed off, packing gland 288 is affixed in its operating position on the upper threaded portion 291 of pipe 17. The relatively large drum reels 281, 285 operated about respective axes 282, 284 by a suitable power drive (not shown) aid in loading tube 14 into the well, and are conventionally disposed elements of many well installation systems. The test van 280 is shown in position, connected by electrical leads 16 to the movable transformer portion 102, and equipped with the power source 230, the demultiplexer 234, and the display equipment 238 of FIG. 5.
In the instrumentation system of FIGS. 2, 5 and 6, data representing the operation of turbine motor-pump system is transmitted from electronic circuit envelope 124 via leads 249, separable transformer elements 194', 163', and leads 16 to test van 280; a power source 230 within van 280 supplies alternating power through leads 16, separable transformer elements 163', 194' and leads 239, tee 250, and leads 248 for operating the circuits within envelope 124. In FIG. 5A, it is indicated that the fixed part 194' of the separable transformer may have a pair of individual windings 194a and 194b, winding 194a being coupled to leads 248 and to filter 251, while winding 194b is coupled by leads 249 to the output of amplifier 255. In this manner, the directly coupling tee junction 250 is desirably avoided.
In more detail, power supply or oscillator 230 supplies power at a first frequency f 1 , say 400 cycles per second, through filter 231 having a narrow passband centered at frequency f 1 and thus through tee junction 232 into the pair of leads 16. The f 1 signal passes down into the well through transformer elements 163', 194' and tee junction 250 into leads 248. It is accepted by filter 251 also having a narrow passband at f 1 for use within envelope 124. For example, it is rectified by rectifier 253 to supply direct voltages to a conventional synchronous multiplexer 256 and to other circuits within envelope 124 such as power amplifier 255, as required.
In this general manner, the signals on output leads 249 of electronic envelope 124 are carrier signals at a carrier frequency f 2 of say, 10,000 cycles per second, bearing multiplexed representations of the signals from sensors 257, 260, 261, 262, et cetera. These readily flow through the leads 249, transformer 194', 163', leads 16, and the f 2 pass filter 233 into synchronous demultiplexer 234, but desirably not through filters 251 or 231.
Device 234 is a conventional kind of synchronous demultiplexer operated synchronously with respect to the operation of the multiplexer 256 of instrumentation section 65 by virtue of the periodic transmission of a synchronizing signal by the latter and its automatic use by demultiplexer 234. The newly separated signals are then coupled from demultiplexer 234 via cable 237 for presentation in any suitable conventional display 238, as upon individual electrical meters of the meter array 238a. They may additionally or separately be recorded by a conventional multichannel recorder 238b. It will further be understood by those skilled in the art that selected ones of the demultiplexed signals may be used for control purposes as indicated in FIG. 5 wherein they may be selectively supplied by cable 235 to a control or assembly of controls represented by control system 236. By way of example, such signals may be used to operate or to augment the operation of power control apparatus such as described in the aforementioned U.S. Pat. No. 3,824,793.
With further reference to FIG. 5, the signal passed by filter 251 may be coupled via leads 254 to carrier generator 258 for generating the carrier frequency f 2 required by synchronous multiplexer 256. Carrier generator 258 may be a conventional frequency multiplier or, alternatively, a stable oscillator excited by the rectified output of rectifier 253'. After synchronous multiplexing, the representations of the signal outputs of sensors 260,261, 262, and the like are amplified by amplifier 255, if desired, and are directed to the earth's surface via isolation filter amplifier 255 and leads 249 and 16, as before. As noted, signals representing other parameters of the down-well equipment may also be supplied to multiplexer 256, as by input terminals 257, for receipt at the earth's surface.
In order to adjust the geothermal well system at the time of its installation for proper and efficient operation at its site and to monitor its subsequent operation so that safe energy production is efficiently maintained, telemetering of performance information from the geothermal pump to the earth's surface is normally required for control or display purposes. Hot water pressures, temperatures, and pump rotation rate are representative parameters, knowledge of which is valuable for assessing productivity of the apparatus or as control terms. For the sake of simplicity, the measured data is communicated by multiplex transmission to the earth's surface using a channel readily provided after the major part of the deep well system has been installed and not requiring removal unless the entire down-well assembly is to be removed for repair. The invention overcomes difficulties of the prior art, obviating the need for the presence of an electrical generator at the deep well pump site. Continuous monitoring is afforded, whether or not the deep well pump is in actual operation. The separable transformer configuration is particularly advantageous during initial or subsequent installations or removals of the pumping system. The invention provides a simple, compact, and reliable solution to the problem of telemetering operational data to the earth's surface.
While the invention has been described in its preferred embodiments, it is to be understood that the words which have been used are words of description rather than of limitation and that changes within the purview of the appended claims may be made without departure from the true scope and spirit of the invention in its broader aspects. | The operation of a geothermal well power-generationsystem is monitored by sensor, communication, and performance monitoring equipment normally associated integrally with the operating power generation system. Sensors detect magnitudes of well water temperature, of water pressure below and above the pump, and of other parameters of interest deep in the well. This data is transmitted by multiplex communication via a novel two-wire line telemetric system to receiver and utilization means at the earth's surface. Power for excitation of deep well monitor units is supplied from the earth's surface also by the two-wire telemetric system. A configuration involving a mechanically separable transformer disposed serially within the two-wire line aids installation of the monitor system and its removal in the rare event that it is required to remove the entire pump from its operating deep well site. | 4 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates generally to bone joint protectors and braces, and more particularly to a unique device which allows rotary movement of the bone joint while the apparatus is in place, supporting and protecting the bone joint. In many situations such as, for example, athletic injury recovery, surgical treatment recovery, and recovery from accident trauma, there is a need for an orthopedic apparatus which will provide some support to the bone joint and surrounding tissue while allowing mobility of the bone joint. Presently there is a need for a bone joint support and protecting apparatus which will allow movement of the bone joint in more than a single plane of motion during the recovery period.
2. Description of the Prior Art
The typical bone joint brace or support is constructed in such a fashion that it supports the bone joint adequately but allows movement of the affected appendage in only one plane. As is common knowledge in the medical arts, many bone joints employ a rotary motion in their normal operation such as, for example, the elbow, ankle, knee, wrist joint, etc.
One such prior art structure was designed to function as a knee brace. The brace included a brace joint formed by a forkhead structure and a flat-sided head held together by a pin. Two arms extended from the joint with one arm extending up the leg to a tie down structure and the second arm extending down the leg to a second tie down structure. The tie down structures held the brace joint adjacent the affected bone joint, while the appliance was in service.
In another prior art structure for a knee brace, a hinge was used which included a rivet having a head and a shank portion. The rivet head overlapped a washer which overlapped the upper end of a connecting bar. The rivet shank extended through a cylindrical hole in the washer, through a hole in the connecting bar, through a hole in a leg structure and terminated in an enlarged shank head. The diameter of the holes were substantially larger than the diameter of the shank below the enlarged head, such that the leg and connecting bar could slide relative to one another and rotate about the rivet. The shank was long enough to enable the leg structure to rock with respect to the connecting bar, thus, the hinge was able to supply substantial mobility to an injured knee.
SUMMARY OF THE INVENTION
The present invention concerns an orthopedic apparatus which is used to support and protect an injured bone joint. The apparatus includes a first support member which is secured to the affected appendage at a point above the bone joint. A first rigid arm extends downwardly from the first support member, and terminates in a male portion, which is generally a spherically shaped enlarged head or ball. A second support member is secured to the affected appendage below the bone joint. A second rigid arm extends upwardly toward the bone joint and terminates in a cup-shaped female member or socket. The female member or socket is configured to accept and retain the male member or spherically shaped ball as a ball and socket joint which allows substantial rotary motion of the affected bone joint.
It is an object of the present invention to provide an orthopedic apparatus capable of supplying support and protection to a bone joint which has been adversely affected by accident trauma, surgical repair or athletic injury.
It is another object of the present invention to provide an orthopedic apparatus which will assist in the rotary motion of the affected bone joint, while providing support and protection for the bone joint.
A further object of the present invention is to provide an orthopedic apparatus which may be fabricated from a minimum of independent parts to reduce the cost of producing such apparatus.
It is another object of the present invention to supplement the flexion and extension of a ball joint and, at the same time, provide maximum protection against new injury as well as against aggravation of an old injury.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a fragmentary perspective view of an orthopedic apparatus for assisting in rotary motion and support of an affected bone joint, according to the present invention;
FIG. 2 is a perspective view of the invention illustrated in FIG. 1 attached to a human leg to support a knee joint;
FIG. 3 is an exploded view of a protective closure capable of surrounding the male and female members of the invention illustrated in FIG. 1;
FIGS. 4a through 4c are cross-sectional views of various embodiments of means for securing the support members to an affected appendage;
FIG. 5 is a perspective view of a restraining collar according to the present invention;
FIG. 6 is a cross-sectional view of a tension adjusting device according to the present invention;
FIG. 7 is a fragmentary cross-sectional view of a shock absorber receiver;
FIG. 8 is a cross-sectional view of a shock absorbing device; and
FIG. 9 is an elevational view of an alternative embodiment of a shock absorbing device.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
There is shown in FIG. 1 an orthopedic apparatus 10 according to the present invention. There is shown in FIG. 2 the orthopedic apparatus 10 installed on a mammalian appendage, in particular, a human leg 12 such that the apparatus 10 provides support and protection for a knee joint 14. The orthopedic apparatus 10 includes a first support member 16, which is C-shaped in lateral section and is typically fabricated of steel or a chromium-vanadium alloy. The support member 16 is formed to be secured to a lateral aspect of the leg. The first support member 16 includes a main body portion 18 having an upper edge 20, a lower edge 22 and a pair of lateral edges 24 and 26. A plurality of apertures 28 are formed near the lateral edges 24 and 26 for securing the main body portion 18 of the first support member 16 to the appendage as will be discussed in detail hereinafter. A cushion member 30 is secured to the inner surface of the first support member 16 to cushion the engagement of the first support member 16 with the leg 12.
A first rigid arm 32 extends from the lower edge 22 of the main body 18 and terminates in a male member 34. In the preferred embodiment, the male member 34 includes a spherically shaped ball 36 which has a shank 38 formed thereon.
The orthopedic apparatus 10 also includes a second support member 40 having a main body portion 42 including an upper edge 44, a lower edge 46, and a pair of lateral edges 48 and 50. A plurality of apertures 52 are formed near the lateral edges 48 and 50. A cushion member 54 is secured to the concave surface of the main body portion 42 to cushion the attachment of the second support member 40 to the leg 12.
A second rigid arm 56 extends from the upper edge 44 of the main body 42. The second rigid arm 56 terminates in a female member 58 including a generally cup shaped socket 60. The socket 60 is complimentary in geometry to the ball 36 of the male member 34 such that when the male member 34 is inserted into the female member 58, there is formed a ball and socket joint.
As shown in FIG. 2, the orthopedic apparatus 10 is utilized by inserting the male member 34 into the female member 58 to form a ball and socket joint and then securing the assembled apparatus 10 to one lateral aspect of the leg 12. The apparatus 10 can be used alone as shown in FIG. 2, or used in connection with a second complementary apparatus, which can be placed on the opposite medial aspect of the leg 12. Rawhide straps 61 (shown in FIG. 2) can be threaded through the apertures 28 and 52 and tied around the leg 12 to secure the apparatus 10 to the lateral aspect of the leg 12.
As shown in FIG. 2, when secured to the leg 12, the apparatus 10 provides a ball and socket joint adjacent to the ball and socket joint of the affected bone joint. When the bone joint is flexed to bring the distal portion of the leg to the rear of the patient, the knee joint 14 flexes in its natural fashion and the ball and socket joint of the apparatus 10 flexes in the same fashion. Note that the ball and socket joint allows support of the patient's knee joint 14 not only for motion in a single plane, the typical forward and backward motion of the knee joint, but also assists in the rotary motion of the knee joint. The shank 38 is formed on the upper portion of the male member 34 so that the ball and socket joint is free to track the movement of the patient's knee joint 14 in its normal path of travel, but will not allow extreme flex in either the lateral aspects or the anterior aspect of its flexation. Therefore, the shank 38 serves to partially limit the flex of the knee joint 14 when such limitation on its rotary motion is in the best therapeutic interest of the patient. The posterior portion of the shank 38 is eliminated from the male member 34 to allow normal flex of the knee joint 14.
In some clinical applications, it may be advisable to secure the apparatus 10 directly to the affected appendage without the benefit of an intervening garmet. In this case, to prevent any discomfort associated with placing cold metal against the leg the entire apparatus, with the exception of the male and female members, can be coated with a suitable coating. For example, a plastic laminate film or a leather sleeve can be used, which will insulate the leg from the cold metal underlying the laminate or sleeve.
In the preferred embodiment, as shown in FIG. 3, the ball and socket joint itself is spaced apart from the outer surface of the leg 12 adjacent the knee joint 14 by a protective closure 62. The protective closure 62 includes a pair of closure walls 64 and 66. A plurality of apertures 68 and 70 are formed about the periphery of the closure walls 64 and 66 respectively. Closure wall pads 72 and 74 are formed on the interior surface of the closure walls 64 and 66 respectively to cushion the contact of the ball and socket joints against the outer surface of the leg 12. The closure walls 64 and 66 are placed around the ball and socket joint and laced together by rawhide straps (not shown) or other suitable closure means to form a protective closure which surrounds the ball and socket joint and cushions the contact of the ball and socket joint with the leg 12.
In the preferred embodiment of the orthopedic apparatus 10 shown in FIGS. 1 and 2, the first and second support members 16 and 40 are secured to the lateral aspect of the leg 12 by lacing rawhide straps 61 through the apertures 28 and 52 in the first and second support members 16 and 40 respectively, and tying the straps 61 together on the opposite medial aspect of the leg. In the event two apparatuses 10 are needed, one apparatus is placed on each aspect of the leg 12, and the two apparatuses are linked together by lacing rawhide straps 61 through the apertures in the apparatuses and tying the straps 61 to secure the apparatuses to the affected leg 12.
FIGS. 4a through 4c show some alternative methods which can be used to secure the support members to the leg 12. FIG. 4a is a cross-sectional view taken through the main body portions 18' of a pair of first support members 16' in contact with a leg 12' above the knee joint. Rawhide straps 76 are used to tie the support members together. Generally, after the support member 16' has been securely tied in intimate contact with the leg 12, an elastic bandage 78 is placed around the support member 16' to assist in maintaining the support member 16' in intimate contact with the leg. The same procedure is used to secure a pair of second support members (not shown) to the leg 12. FIG. 4b shows an alternative embodiment wherein only an elastic bandage 78' is used to secure the first support members 16" to the leg 12". Alternatively, as shown in FIG. 4c, the first support members 16"' can be joined together by a spring hinge 80 at the posterior of the leg, provided that, the spring hinge is separated from the leg 12"' by a protective liner 82. The spring hinge can include a pair of springs, if advantageous. As in the other embodiments, the elastic bandage 78"' can be employed to assist in securing the support members in intimate contact with the leg 12"'.
During normal service, no active mechanical support is needed to maintain the ball 36 in the socket 60. The opening in the socket is slightly smaller in diameter than the ball. The ball and socket are assembled by heating the socket 60 to a fairly high temperature and lowering the temperature of the ball 36 so that the socket expands and the ball contracts to allow the ball 36 to pass through the hole in the socket 60. After the ball 36 has been placed in the socket 60, the ball 36 and socket 60 are allowed to come to room temperature to assume their normal geometries. This operation secures the ball 36 within the socket 60 while allowing it free rotary movement within the path of travel defined by the shank 38.
In some instances, however, the ball 36 and socket 60 are stressed to the point where they could disengage from one another. FIG. 5 shows an embodiment of the invention wherein a restraining collar 84 is used to maintain the ball 36 and socket 60 in contact with each other during periods of excess stress which would cause them to disengage. The restraining collar 84 includes a back plate 86 with outwardly depending legs 88 and 90. The leg 88 terminates in a metal ring 92, while the leg 90 terminates in a metal ring 94. The rings 92 and 94 surround the first rigid arm 32 and second rigid arm 56 respectively. The rings 92 and 94 are positioned near enough to the ball 36 and the cup 60 to restrain their motion along the longitudinal axis defined by the first and second rigid arms 32 and 56. Thus, the restraining collar 84 serves to hold the ball 36 within the socket 60 when there is sufficient stress to cause the ball 36 to disengage from the socket 60.
In some cases it is advisable to increase the tension between the first support member 16 and the second support member 40 as much as possible without causing the ball 36 to disengage with socket 60 in flexion. In this case, a tension adjusting device 96, shown in FIG. 6 as a turn buckle, is employed to provide the necessary tension between the support members 16 and 40. The tension adjusting device 96 can be placed in either the rigid arm 32 or 56. In FIG. 6, the rigid arm 56 is separated and external threads 98 and 100 are formed on the facing ends. The threads 98 are typically left-hand threads while the threads 100 are typically right-hand threads. An internally threaded housing 102 is formed to accept the threaded ends of the arm 56. As the internally threaded housing 102 is rotated, the two portions of the arm 56 are threadingly engaged and drawn outwardly of the housing 102. When sufficient tension has been achieved between the support members 16 and 40, rotation of the housing 102 is stopped. To maintain the appropriate tension, a pair of internally threaded locking nuts 104 and 106 are rotated until they engage the ends of the housing 102. The locking nuts hold the two parts of the arm 56 within the housing 102 to maintain the desired tension between the support members 16 and 40.
In some cases, it is advisable to include a shock absorbing device in one of the rigid arms to absorb extreme vertical stresses which could be placed upon the ball and socket joint from impacts which could be experienced by wearers, for example, athletes. FIG. 7 shows a fragmentary cross-sectional view of a shock absorber receiver 108 capable of accepting a shock absorbing insert, described in detail hereinafter. For purposes of illustration, the receiver 108 is shown integral with the second rigid arm 56 of the apparatus 10. The receiver 108 includes a first housing 110, a second housing 112 and a restraining sleeve 114. The first housing 110 is generally cup shaped with a closed end formed integral with the rigid arm 56 of the apparatus 10. The first housing includes wall 116 which terminates in a closed end 120. A threaded stud 122 is formed in the center of the end inside the housing 120. A set of threads 124 are formed on the outer surface of the wall 116. The second housing 112 is also cup shaped with a wall 128 and a closed end 130. The wall 128 terminates opposite the closed end in a flange 132. The closed end 130 includes a centrally located threaded stud 134, formed inside the housing.
The first housing 110 and the second housing 112 are held together by the restraining sleeve 114. The restraining sleeve 114 has a flange 140 formed at one end and an internal set of threads 142, which are adapted to engage the threads 124 on the first housing 110, formed at the other end. A knurled area 144 is included on the exterior surface of the sleeve 114 to assist in snugly securing the first housing 110 to the sleeve 114.
FIG. 8 shows one embodiment of a shock absorbing device 146 which can be utilized with the receiver 108. The device includes a piston housing 148 and a cylinder housing 150. The piston housing 148 is generally cup shaped and includes a wall 152 and an enclosed end 154. The end 154 has a threaded aperture 156 formed thereon for engaging the threaded stud 122 of the receiver 108. The end 154 also has a central post 158 formed therein which extends into the cup shaped cavity defined by the wall 152. A piston 160 is attached to the end of the post 158 and has a pair of apertures 162 formed therein connecting the opposite faces of the piston 160. A flap valve 164 is attached to each of the opposing surfaces of the piston to cover one end of each of the apertures 162.
The cylinder housing 150 is generally cup shaped and includes a wall 166 and an enclosed end 167. The end 167 has a threaded aperture 168 formed therein for engaging the threaded stud 134 of the receiver 108. The piston 160 is sealed to the internal surface of the wall 166 and the external surface of the wall 166 is sealed to the internal surface of the wall 152 by a pair of O-rings 169. The cavities formed on either side of the piston 160 can be filled with hydraulic fluid through access holes (not shown). The flap valves 164 allow the passage of the hydraulic fluid in one direction, one operating during compression and one during decompression.
FIG. 9 shows an alternative embodiment of a shock absorbing device for use with the receiver 108. A helical spring 170 has a pair of internally threaded nuts 172 attached to the opposite ends thereof. The nuts are threadably engaged by the studs 122 and 134 in the receiver 108.
In summary, the present invention concerns an orthopedic apparatus capable of supporting and protecting a bone joint while allowing rotary movement and flexion of the joint when the apparatus is in place. The apparatus includes a first support member which is secured to an affected appendage on one side of the joint to be treated. A first rigid arm extends from the first support member and terminates in a ball adjacent the joint. The ball seats into a socket which is attached to a second rigid arm which extends from a second support member. The first and second support members are brought into intimate contact with the appendage and secured thereto by an elastic bandage and/or with rawhide straps threaded through apertures in the support members.
In accordance with the provisions of the patent statutes, the principle and mode of operation of the invention have been explained and illustrated in its preferred alternative embodiments. However, it must be understood that the invention may be practiced otherwise then as specifically illustrated and described without departing from its spirit or scope. | An orthopedic apparatus to be worn by a person such as an athlete, trauma victim or surgical patient, to protect and supplement the function of a bone joint. The apparatus comprises a first support member adapted to be placed on one lateral aspect of an appendage above the bone joint to be treated. A first rigid arm extends from the first support member and terminates in a male member adjacent the bone joint. A second support member is placed on the same lateral aspect of the appendage as the first support member and positioned below the bone joint to be treated. A second rigid arm extends upwardly from the second support member and terminates in a female member at a point adjacent the bone joint to be treated, such that the male and female members cooperate to form a ball and socket joint. The support members are secured to the appendage so that the ball and socket joint remains adjacent the bone joint to protect and supplement the function of the bone joint. Where needed, one appliance can be placed on each aspect, medial and lateral, of the appendage to be treated to provide added support and protection for the bone joint. | 0 |
FIELD OF APPLICATION
[0001] The present invention refers to a method for producing cladribine (2-chloro-2′-deoxyadenosine).
[0002] More specifically, the invention refers to a method for producing cladribine by means of a transglycosylation reaction.
PRIOR ART
[0003] As is known, cladribine (2-chloro-2′-deoxyadenosine) is a molecule used as antineoplastic drug in the treatment of leukaemia and other neoplasias and has the following formula (I):
[0000]
[0004] Various synthesis methods of Cladribine have been described; among these we highlight the following.
[0005] The U.S. Pat. No. 5,208,327 (Chen, R. H. K., filed on 16 Apr. 2002) describes a synthesis method of the cladribine starting from guanosine in 7 chemical synthesis steps with the use of numerous reagents.
[0006] The U.S. Pat. No. 6,252,061 describes a synthesis which foresees a direct halogenation of 2,6-diaminopurine deoxyribose in a mixture of protic and aprotic solvents, in the presence of a Lewis acid and an organic nitrite. The synthesis foresees a column purification of the final product.
[0007] The international patent application WO 2004/028462 describes a synthesis for direct halogenation of 2′-deoxyguanosine followed by a chromatographic separation for every intermediate.
[0008] The patent application EP 173 059 describes a synthesis which foresees a condensation of a purine base and an adequately protected deoxyribose.
[0009] The US patent application No. 2002/0052491 describes a synthesis beginning from Chloroadenine and adequately protected deoxyribose, with improved yields with respect to EP 173,059 and elimination of the column purification step.
[0010] The US patent application No. 2004/0039190 describes a reaction between adequately protected chloroadenine and adequately protected deoxyribose, with improved yields with respect to US 2002/0052491.
[0011] Cladribine production by means of chemical synthesis processes has significant limitations, since such processes often consist of multiple-stage reaction, which comprise protection and deprotection reactions starting from compounds which are costly and/or hard to find on the market, and sometimes involve non-stereospecific reactions (i.e. which lead to the production of the final product in both α and β conformations). Such processes are therefore long and costly, and the yields are rarely satisfying. These process types, therefore, by their nature, do not lend themselves to be employed on an industrial scale.
[0012] On the other hand, enzymatic reactions, such as for example glycosylation and transglycosylation reactions, better lend themselves for use on an industrial level and the variety of enzymes available in nature permit selecting the desired stereospecificity and regioselectivity of the reaction. Such reactions usually require, then, a final step of purification (for example by means of precipitation or filtration) of the product mixture in order to isolate, to the desired purity level, the product from the enzyme, the unreacted substrate and from possible reaction co-products (for example isomers).
[0013] Another advantage of the enzymatic reactions with respect to the synthesis reactions is the fact that the enzymes which are used, in addition to being available on the market, are also easily found in large quantities and at low cost, in nature, for example from the cultivation of bacterial cells.
[0014] It is therefore possible to cultivate the bacteria which produce the enzyme of interest and isolate the enzyme from the bacterial cells. Alternatively, the enzymatic reactions can be carried out by using whole bacterial cells, the latter solution usually leading to less efficient reactions (with therefore lower yields) which are however more convenient and economical.
[0015] The enzymatic reactions can then be classified into free enzyme reactions and immobilised enzyme reactions. In the first case, the enzymes are added to the reaction mixture, while in the second case the enzymes (or the bacterial cells) are immobilised on appropriate carriers.
[0016] The immobilisation of the enzymes or bacterial cells leads to the advantage of not having to separate the enzymes from the product mixture at the end of the reaction and of allowing, therefore, to recover the enzymes or the cells and reuse them for a subsequent reaction. The immobilisation moreover enables to carry out the reactions continuously or in batches, therefore obtaining higher yields and attaining greater suitability for use on an industrial scale.
[0017] Finally, the enzymatic reactions can be optimised by means of genetic manipulation of the bacteria which produce the enzyme. Such manipulation is usually aimed to confer a greater enzyme yield or enzymatic activity. It can regard, nevertheless, other factors such as the suppression of the production of other possible enzymes by the microorganism, the stereoselectivity or regioselectivity of the enzyme of interest, etc.
[0018] Enzymatic reactions for producing cladribine are described in numerous articles and patents. Among these we highlight the following.
[0019] In Michailopulo, I A et al (1993) Nucleosides & Nucleotides, 13 (3&4) 417-422, the biochemical synthesis of Cladribine is described beginning from chloroadenine and deoxyguanosine in the presence of E. coli cells.
[0020] The US patent application No. 2006/0094869 describes a reaction between chloroadenine and deoxyribose-1-phosphate in the presence of the purified purine nucleoside phosphorylase (PNP) enzyme.
[0021] The abovementioned documents describe production processes of the cladribine which while advantageous with respect to the chemical methods set forth above, nevertheless involve various drawbacks, including low yields, substrates (for example deoxyguanosine and deoxyribose 1-phosphate) which are hard to find and finally process steps (such as the final isolation on column chromatography) of difficult industrial application.
[0022] The latter step of isolation and purification of the final product has generally been the most problematic for the entire production process of the cladribine through enzymatic means.
[0023] The technical problem underlying the present invention is therefore that of making available a method for the production of cladribine which permits obtaining product yields which are equal to or greater than those of the prior art, starting from economical, easy-to-find raw materials, and which is at the same time economically advantageous and permits an easy isolation of the final product.
SUMMARY OF THE INVENTION
[0024] One such problem is resolved according to the present invention by a method for producing cladribine (2-chloro-2′-deoxyadenosine) comprising the steps of:
[0000] a) reaction of 2-deoxyuridine with 2-chloroadenine, in the presence of uridine phosphorylase (UPase) and purine nucleoside phosphorylase (PNPase) in an aqueous reaction medium possibly containing up to 40% v/v of an aprotic dipolar solvent, to obtain cladribine dissolved in said reaction medium;
b) isolation of the cladribine by precipitation by means of concentration and alkalinisation of the reaction medium up to a pH of 11.5-12.5.
[0025] The enzymes UPase and PNPase can be present in the reaction medium in the form of free enzymes or enzymes immobilised on adequate carriers, or they can be produced in situ by cells which produce them, which in turn can be present in the reaction medium in a free form or in immobilised form.
[0026] When producer cells of UPase enzymes or producer cells of PNPase enzymes are used, or when producer cells of both the enzymes UPase and PNPase are used, such cells are preferably immobilised by adsorption onto a weak anion exchange resin, in particular onto a weak anion exchange resin having amine functional groups. Particularly preferred is a resin chosen from the group comprising the Dowex MWA1 (Dow Chemical), Diaion WA30 (Mitsubishi), Duolite A7®, Amberlite FPA54®, Amberlyst 21 and Duolite A568° (Rohm & Haas) resins. The latter resin is particular preferred for the objects of the present invention.
[0027] The process for obtaining the immobilisation of UPase and/or PNPase producer cells onto weak anion exchange resins is described in application EP 06005241 of the same Applicant.
[0028] According to an embodiment of the invention, the aforesaid cells are cells of the Escherichia coli species.
[0029] Particularly preferred is the use of Escherichia coli cells of the DH5alpha strain, transformed by means of plasmid vectors having the sequences reported in Sequence Id No. 1 and 2.
[0030] The aforesaid aprotic dipolar solvent is generally represented by dimethylformamide or by dimethylsulphoxide or mixtures thereof and is preferably dimethylformamide.
[0031] The aforesaid alkalinisation step is preferably carried out so as to obtain a pH equal to about 12.
[0032] Preferably the 2-deoxyuridine and the 2-chloroadenine are reacted in a molar ratio ranging from 1:1 to 3:1, advantageously about 2:1.
[0033] The reaction between 2-deoxyuridine and 2-chloroadenine is generally carried out in a buffered medium, for example by means of a phosphate buffer, at a pH in the range of 6.5-8.5, preferably 7.3-7.8.
[0034] The reaction is generally conducted at a temperature in the range of 50-70° C., suitably at about 60° C.
[0035] According to a further aspect of the present invention, the reaction between 2-deoxyuridine and 2-chloroadenine is carried out by gradually adding, to the aqueous reaction medium buffered to pH 7-8 and containing the enzymes and the 2-deoxyuridine, a solution of 2-chloroadenine in a mixture of water and aprotic dipolar solvent, at a speed such that the 2-chloroadenine remains in solution until it has been converted into the final product, i.e. such that no precipitation of 2-chloroadenine occurs during the reaction.
[0036] The aforesaid solution of 2-chloroadenine is preferably prepared by suspending the 2-chloroadenine in an aprotic dipolar solvent and adding a concentrated solution of an alkaline hydroxide until a complete dissolution of the 2-chloroadenine is obtained.
[0037] The aprotic dipolar solvent in question is preferably dimethylformamide and the alkaline hydroxide is preferably KOH, used in a concentration in the range of 20-30% w/v.
[0038] The addition is foreseen of an aqueous solution of a strong acid at the same time as the addition of the 2-chloroadenine solution, at such an extent as to maintain the pH of the reaction mixture between 6.5 and 8.5, preferably between 7.3 and 7.8.
[0039] As the strong acid, mineral acids such as HCl or H 3 PO 4 can be used, or organic acids can be used such as, for example, citric acid.
[0040] The aforesaid steps of concentration and alkalinisation of the reaction medium at the end of the reaction can be carried out in any order but preferably the alkalinisation is carried out first, followed by the concentration.
[0041] When immobilised enzymes or immobilised cells are used, before proceeding with the alkalinisation and concentration steps, a filtration or centrifugation step is carried out to remove the immobilised enzymes or immobilised cells from the reaction mixture.
[0042] The precipitate obtained at the end of such steps is filtered and possibly recrystallised with a hydroalcoholic mixture, for example with 95:10 ethanol/water v/v.
[0043] Thanks to the method according to the present invention, it is possible to carry out a stereospecific reaction, which leads to the formation of high yields of the desired product only in its β configuration. Moreover, the method according to the present invention resolves the drawbacks mentioned in the prior art and permits isolating the cladribine produced in an extremely simple, effective and economical manner, thus making the method easily transferable to an industrial production. In particular, the isolation step of the cladribine from the other components of the reaction mixture is brilliantly executed with a simple variation of the pH, without having to resort to costly chromatographic separations, and it permits obtaining the product with a high level of purity.
DETAILED DESCRIPTION
[0044] As stated above, it is preferred to conduct the transglycosylation reaction according to the invention by using, rather than UPase and PNPase enzymes as such, immobilised Upase- and/or PNPase-producing cells. Such cells are preferably cells of genetically modified Escherichia coli , capable of expressing considerable quantities of UPase or PNPase.
[0045] Such cells were obtained in the following manner:
1. Construction of Recombinant Strains Expressing the UPase Enzyme or PNPase Enzyme
[0046] The recombinant strains were constructed by transforming a host strain of Escherichia coli with a plasmid with a high number of copies containing the gene of interest and a marker for the selection.
[0047] The host strain used is the DH5alpha strain, found easily on the market (GIBCO-BRL) and extensively described in the literature. It is a strain derived from Escherichia coli K12 and therefore considered of safety class 1, thus adapted for a use of industrial type.
[0048] The gene UdP, coding for the UPase enzyme, and the gene deoD, coding for the PNPase enzyme, have already been well described in literature and their sequences are known and available at the EMBL databank, characterised by the accession numbers X15679 for UdP and M60917 for deoD.
[0049] Genes were amplified by means of PCR (polymerase chain reaction) using suitably prepared synthetic primers.
[0050] The genes were inserted, using the appropriate restriction enzymes KpnI and SalI for UdP and EcoRI and SalI for deoD, in the zone of the polylinker of the plasmid with a high number of pUC18 copies, well characterised in literature and commercially available.
[0051] In both plasmids (that containing the UdP gene and that containing the deoD gene), the resistance to the kanamycin antibiotic was then inserted, obtained by means of digestion with the HindIII restriction enzyme of the pBSL14 plasmid, which is commercially available.
[0052] Finally, for both plasmids (that containing the UdP gene and that containing the deoD gene), the resistance to Ampicillin was destroyed through deletion, by means of digestion with the AvaII enzyme.
[0053] Unexpectedly, two sites recognised by the restriction enzyme AvaII were found, with the consequent formation of 3 plasmid fragments rather than the two expected, whereas in literature only one restriction site for this enzyme is reported.
[0054] The final plasmids were obtained by recovering the two larger fragments and eliminating the unnecessary fragment which had formed. The main characteristics of the new genetically modified strains are reported in the following table.
[0000]
TABLE
Selection
Expressed
AmpR
STRAIN
Host
Plasmid
marker
protein
presence
EXP05/03
DH5alpha
pUC18
Kanamycin
UPase
No
EXP05/04
DH5alpha
pUC18
Kanamycin
PNPase
No
[0055] The sequence of the plasmids pursuant to the preceding table are reported in the lists at the end of the description and in particular the sequence of the pUC18 plasmid containing the UdP gene corresponds to Sequence Id. No. 1 and the sequence of the pUC18 plasmid containing the deoD gene corresponds to Sequence. Id. No. 2.
2. Preparation of the Biocatalyst
[0056] The biocatalyst is prepared using genetically modified strains of Escherichia coli which are capable of over-expressing the phosphorylase activities due to the Uridine Phosphorylase and Purine Nucleoside Phosphorylase enzymes, in the specific case the strains EXP05/03 and EXP 05/04. The immobilisation of cell suspensions containing the UPase enzymatic activity and the PNPase enzymatic activity is prepared starting from a mixture of cell suspensions prepared so to have a ratio between the enzymatic activity due to the UPase enzyme and the enzymatic activity due to the PNPase enzyme in the range of 1:1-3:1. In this example, the immobilisation is described of a mixture of cell suspensions in which the ratio between the enzymatic activity due to the UPase enzyme and the enzymatic activity due to the PNPase enzyme is about 3:1.
[0057] About 20 (dry weight) grams of Rohm & Haas Duolite A568 resin is added to 200 ml of a mixture of cell suspensions composed of cells containing the UPase enzymatic activity (EXP05/03) in the measure of about 115 units/ml and of cells containing the PNPase enzymatic activity (EXP 05/04) in the measure of about 33 units/ml.
[0058] The mixture is held at room temperature with moderate stirring for 48 hours. The immobilisation mixture is then filtered. The resin is washed with water until clear washing waters are obtained (about 2 litres).
[0059] The resin with the immobilised enzymatic activities is then preserved at 4° C. in 0.1 M potassium phosphate buffer at pH 7.5.
[0000] 3. Activity of the Resin with Immobilised Cells
[0060] The catalytic activity of the enzymes UPase and PNPase coupled in the resin with immobilised cells is determined with a transglycosylation reaction carried out using standardised conditions.
[0061] 200 g or 400 g of solid carrier with immobilised cells containing the UPase enzymatic activity and the PNPase enzymatic activity (wet weight) as described in the preceding point is added to 10 ml of reaction mixture.
[0062] The reaction is carried out with the following solution: 40 mM arabinofuranosyluracil (Ara-U), 40 mM adenine, 30 mM monobasic potassium phosphate—pH 7.2, at a temperature thermostated at 60° C. After 60 minutes at 60° C., the reaction is stopped by diluting the reaction 1:50 in water. The percentage of adenine converted into arabinofuranosyladenine (ARA-A) is determined by analysing an aliquot of the reaction mixture with a high performance liquid chromatograph (HPLC) equipped with a Nucleosil 100-5 column (Macherey-Nagel) of 250×4.6 mm size, eluting with a 10 mM monobasic potassium phosphate buffer −6% methanol. The catalytic activity of the coupled UPase and PNPase enzymes (catalytic activity of transglycosylation) is expressed in units/wet g (micromoles per minute of Adenine converted to form ARA-A in the assay conditions/wet weight gram of cell paste) and is calculated with respect to the adenine conversion percentage.
4. Fermentation of the Cells Containing the UPase Enzymatic Activity or the PNPase Enzymatic Activity
[0063] The recombinant strains EXP05/03 (coding for the UPase enzyme) and EXP05/04 (coding for the PNP enzyme) were separately fermented batchwise by using a fermenter with a useful volume of 15 litres, containing 15 of culture medium with the following composition (per litre):
13.3 g KH 2 PO 4 ;
[0064] 40 g soitone;
36 g yeast extract;
1.5 g MgSO 4 .7H 2 O;
[0065] 0.02 g kanamycin
[0066] The fermenter was inoculated with about 150 ml of bacterial suspension which had previously been grown for about 24 h at 37° C. The fermentation was carried out using the following parameters: 37° C. temperature, mechanical stirring of about 250 r.p.m., air flow automatically controlled to hold the pO 2 value at 20% of the saturation concentration, pH controlled at 7+0.2 by means of the addition of a 10% ammonia solution or a 20% phosphoric acid solution.
[0067] Once the fermentation is terminated (completed in about 24 hours), the cell paste was collected for centrifugation, washed with 100 mM potassium phosphate buffer at pH 7.0, collected once again for centrifugation and preserved in the form of wet cell paste at a temperature of −20° C.
5. Determination of the Enzymatic Activities
a) Determination of the Enzymatic Activity Due to the UPase Enzyme.
[0068] A known quantity (100 or 200 microlitres) of suspension of the cells which express the UPase enzyme (EXP05/03), diluted 1:100 or 1:1000 as wet weight/volume in potassium phosphate buffer at pH 7.0-7.2, is added to 800 microlitres of a 75 mM Uridine solution in 100 mM, pH 7.0-7.2 phosphate buffer, pre-incubated at 30° C. After exactly 5 minutes, the phosphorolysis reaction is stopped with the addition of 1 ml of HCl. An aliquot of the reaction mixture is analysed with a high performance liquid chromatograph (HPLC) equipped with a Nucleosil 100-5 column (Macherey-Nagel) of 250×4.6 mm size. The elution is carried out with a 10 mM monobasic potassium phosphate solution −6% methanol.
[0069] The enzymatic activity of the cell paste is expressed as units/gram of wet weight (micromoles transformed per minute per 1 gram of wet cell paste) and is calculated with respect to a standard curve constructed with the uracil quantities formed in the same assay conditions, using increasing quantities of the same cell paste.
b) Determination of the Enzymatic Activities Due to the PNPase.
[0070] A known quantity (100 or 200 microlitres) of suspension of the cells which express the PNPase enzyme (EXP05/04), diluted 1:100 or 1:1000 as wet weight/volume in potassium phosphate buffer at pH 7.0-7.2, is added to 800 microlitres of a 60 mM Inosine solution in 100 mM, pH 7.0-7.2 phosphate buffer, pre-incubated at 30° C. After exactly 10 minutes, the phosphorolysis reaction is stopped with the addition of 1 ml of HCl. An aliquot of the reaction mixture is analysed with a high performance liquid chromatograph (HPLC) equipped with a Nucleosil 100-5 column (Macherey-Nagel) of 250×4.6 mm size. The elution is carried out with a 10 mM monobasic potassium phosphate solution −6% methanol. The enzymatic activity of the cell paste is expressed as unit/gram of wet weight (micromoles transformed per minute per 1 gram of wet cell paste) and is calculated with respect to a standard curve constructed with the hypoxanthine quantities formed in the same assay conditions, using increasing quantities of the same cell paste.
6. Solubility of 2-Chloroadenine
[0071] 0.42 g (equal to 2.5 mMoles) of 2-chloroadenine were suspended in 50 ml of DMF and heated while being stirred. Aliquots of DMF were added until a complete hot solubilisation was obtained. 100 ml of solvent were necessary to obtain the solubilisation of the 2-chloroadenine.
[0072] A solubilisation test was also carried out of 2-chloroadenine in 25% KOH in order to increase the solubilisation. 4.05 grams of 2-chloroadenine were resuspended in KOH being stirred. Aliquots of (25% w:v) KOH were added until complete solubilisation was obtained. Even after the addition of 100 ml of 25% KOH, the 2-chloroadenine remained practically undissolved. Even in very concentrated KOH the molecule was practically insoluble.
7. Reaction in 20% DMF
[0073] A transglycosylation reaction was carried out using 2-chloroadenine solubilised in DMF. 0.42 grams (equal to 2.5 mMoles) of 2-chloroAdenine were suspended and hot-solubilised while being stirred in 100 ml of DMF, up to boiling, obtaining a 25 mMolar solution.
[0074] To 25 ml of this solution, thermostated at 60° C., 80 ml were added of a solution of 18.75 mM 2′-d-Uridine and 37.5 mM KH 2 PO 4 at pH 7.3 for the KOH, heated to 70° C. During the addition of this solution, there occurred the formation of precipitate which remained undissolved even by heating once again to boiling.
[0075] The test has been repeated by adding the 2′-d-Uridine/KH 2 PO 4 solution dropwise. After a small addition, the formation of precipitate is noted, which is slowly dissolved by stopping the addition. The remainder of the solution was added at very small aliquots, allowing the situation to equilibrate.
[0076] Thus, a clear solution was obtained to which 5 grams of resin were added with immobilised cells with an activity of 5 units/wet gram of resin (measured as in point 3).
[0077] The final mixture had a 15 mM d-uridine concentration; 5 mM 2-chloroadenine; 30 mM KH 2 PO 4 ; resin with of immobilised cells: 250 units/litre of reaction.
[0078] The reaction was followed by HPLC and after 3 hours there was the conversion of about 80% of the 2-chloroadenine into cladribine.
8. Reaction in DMF/KOH
[0079] To increase the solubility of the 2-chloroadenine in DMF, concentrated bases or acids were added and in both cases a greater solubilisation was obtained.
[0080] The acidic environment, however, can degrade the deoxynucleosides, therefore tests were only carried with the addition of concentrated KOH.
[0081] 4.05 grams (equal to 24 mMoles) of 2-chloroAdenine were weighed and suspended in 50 ml of DMF. 30 ml of 25% KOH (w:v) were added. There remained a slight opalescence which disappeared with the addition of 10 ml of H 2 0, obtaining a 266 mMolar solution. To this solution, thermostated at 60° C., 600 ml were added of a pH 7.3 solution containing 10.95 grams (equal to 48 mMoles) of 2′-d-uridine and 4 grams of KH2PO4 (equal to 30 mMoles). Incipient precipitation of the 2-chloroadenine was obtained.
[0082] The preparation of the two solutions was repeated. 30 wet grams of resin with immobilised cells were added (5 U/wet gram calculated as in point 3) to the 2′-d-Uridine solution, thermostated at 60° C.
[0083] The solution of 2-chloroadenine in DMF/KOH was very slowly added to this suspension, so to prevent the precipitation of the 2-chloroadenine. In this manner, if the addition occurred at an appropriate speed, most of the added 2-chloroadenine was transformed into Cladribine before reaching a concentration such to cause precipitation.
[0084] With the addition of the 2-chloroadenine in DMF/KOH, the pH of the reaction started to increase, and since the enzymatic activities functioned in optimal manner at physiological pH values, it was necessary to add hydrochloric acid to maintain the pH at the desired values.
[0085] At the end of the additions, there were the following concentrations:
[0086] 35 mMolar 2-chloroadenine; 70 mMolar 2-deoxyuridine; 37.5 mM KH 2 PO 4 ; resin with immobilised cells: 220 U/litre of reaction.
[0087] In these conditions, a conversion of 80% of the 2-chloroadenine into cladribine was obtained.
[0000] 9. Reaction with Controlled Addition
[0088] After having carried out different preliminary optimisation tests, a reaction was carried out for preparing the Cladribine, adding the 2-chloroadenine substrate and the pH corrector in a controlled manner.
[0089] 6.75 grams (equal to 40 mMoles) were weighed of 2-chloroadenine and were suspended while being stirred in 50 ml of DMF. Solubilisation occurred with the addition of 70 ml of 25% KOH (w:v), obtaining a perfectly clear solution with a 333 mMolar concentration. 18.25 grams (equal to 80 mMoles) of 2′-deoxyUridine and 4 grams (equal to 30 mMoles) of anhydrous monobasic potassium phosphate were added and solubilised in 600 ml of deionised water, obtaining a 133 mM concentration for the 2-deoxyuridine and 50 mM for KH 2 PO 4 . The pH was corrected to a value of 7.5 with 25% (w:v) KOH as required.
[0090] The 2′-deoxyUridine solution in phosphate buffer was loaded into a 1 litre reactor thermostated at 60° C. with mechanical stirring.
[0091] 30 wet grams of just filtered resin with immobilised cells, prepared as in point 2, were added to the reactor.
[0092] The specific activity of the resin with immobilised cells (measured as reported in point 3) was 5 U/wet gram.
[0093] The solution of 2-chloroadenine in KOH/DMF was slowly added to the suspension of 2′-deoxyUridine in phosphate buffer and resin with immobilised cells. The addition was carried out by means of a peristaltic pump with silicone tube with 1.5 mm inner diameter, at a flow rate of about 1 ml/min (equal to 0.33 mMoles/minute).
[0094] To maintain the pH at optimal values, a 2N hydrochloric acid solution was added simultaneously to the solution of 2-chloroadenine in DMF/KOH, so to maintain the pH value in the range of 6.5-8.5, preferably in the range of 7.3-7.8.
[0095] The addition of 2N HCl was carried out with a peristaltic pump equipped with silicone tube with 1.5 mm inner diameter and flow rate of about 1 ml/min.
[0096] With respect to the final volume, there were the following concentrations:
[0000] 50 mMolar 2-chloroadenine; 100 mMolar 2-deoxyuridine; 37.5 mM KH 2 PO 4 ; resin with immobilised cells: 187.5 U/litre of reaction.
[0097] At the end of the addition, the reaction was filtered on paper. The resin was recovered and stored in 100 mM phosphate buffer at pH 7.4, at a temperature of 4° C., while the filtrate was processed for the isolation of the cladribine. In these conditions, about 80% of the 2-chloroadenine was converted into cladribine.
[0000] 10. Reaction with Controlled Addition in DMSO
[0098] The same reaction pursuant to point 8 was carried out using the dimethylsulphoxide as solvent for the solubilisation of the 2-chloroadenine instead of the dimethylformamide.
[0099] 5.4 grams (equal to 32 mMoles) of 2-chloroadenine were weighed and suspended while being stirred in 50 ml of DMSO. Solubilisation occurred with the addition of 70 ml of 25% (w:v) KOH, obtaining a perfectly clear solution with a 266 mMolar concentration of 2-chloroAdenine. 14.6 grams (equal to 64 mMoles) of 2′-deoxyuridine and 4 grams (equal to 30 mMoles) of anhydrous monobasic potassium phosphate were dissolved in about 600 ml of deionised water, obtaining a 106 mM for the 2-deoxyUridine and 50 mM for KH 2 PO 4 . The pH was corrected to a value of 7.5 with 25% (w:v) KOH as required.
[0100] The 2′-deoxyUridine solution in phosphate buffer was loaded into a 1 litre reactor thermostated at 60° C. with mechanical stirring.
[0101] 30 wet grams of just filtered resin with immobilised cells, prepared as in point 2, were added to the reactor.
[0102] The specific activity of the resin with immobilised cells (measured as reported in point 3) was 5 U/wet gram.
[0103] The solution of 2-chloroadenine in KOH/DMF was then slowly added to the suspension of 2′-deoxyuridine in phosphate buffer and resin with immobilised cells. The addition was carried out by means of a peristaltic pump with a silicone tube with 1.5 mm inner diameter, at a flow rate of about 1 ml/min (equal to 0.26 mMoles/minute).
[0104] To maintain the pH at optimal values, a 2N hydrochloric acid solution was added simultaneously to the solution of 2-chloroadenine in DMF/KOH, so to maintain the pH value in the range of 6.5-8.5, preferably in the range of 7.3-7.8.
[0105] The addition of 2N HCl was carried out with a peristaltic pump equipped with silicone tube with 1.5 mm inner diameter and flow rate of about 1 ml/min.
[0106] With respect to the final volume, there would have been the following concentrations:
[0107] 40 mMolar 2-chloroadenine; 80 mMolar 2-deoxyuridine; 37.5 mM KH 2 PO 4 ; resin: 187.5 U/litre of reaction.
[0108] At the end of the addition, the reaction mixture was filtered on paper. The resin was recovered and stored in 100 mM phosphate buffer at pH 7.4, at a temperature of 4° C., while the filtrate was processed for the isolation of the cladribine. In these conditions, about 80% of the 2-chloroadenine was converted into cladribine.
11. Addition of Different Acids
[0109] The pH can be controlled and maintained constant around optimal values by also using phosphoric acid, in addition to hydrochloric acid, permitting the completion of the reaction without encountering problems of precipitation of the 2-chloroadenine. Equivalent results were obtained by using a solution of 5% phosphoric acid instead of 2N hydrochloric acid.
12. Recycling of the Resin
[0110] The resin with immobilised cells used for one reaction, after having been filtered and separated from the reaction mixture, was stored at 4° C. in phosphate buffer or immediately used for a subsequent reaction.
[0111] The resin with immobilised cells (prepared as in point 1) was used, with equivalent final yields, for at least 4 subsequent reactions.
[0112] The presence of DMF in the 2-chloroadenine solution, the relatively high temperature and the addition of concentrated acid and base solution did not cause drastic diminutions of the biocatalyst activity.
13. Purification Tests
[0113] The filtered reaction mixture was processed so to be able to isolate and purify the cladribine from the other components of the reaction.
[0114] The filtered reaction mixture was concentrated in a Rotavapor until the initial volume was reduced by about 3 times, and was transferred first at room temperature and then at 4° C. Precipitate was formed which was separated by filtration and which was composed essentially of unreacted 2-chloroadenine and by uracil formed during the reaction.
[0115] Precipitation tests were carried out on the resulting mother liquors by varying the pH value.
[0116] Tests were conducted at pH 4.0-7.0-10.0-12.0.
[0117] At an acidic pH, there was the formation of precipitate, which was formed only by inorganic salts.
[0118] At pH values 7.0 and 10.0, the precipitate was obtained composed essentially of cladribine and uracil, the latter in considerably quantities.
[0119] Only with the pH 12.0 test was a precipitate obtained, which was found to be cladribine with high purity. To increase the yield, the pH change was repeated on a solution which was 5 times more concentrated, a high purity product always being obtained.
[0120] By concentrating 10 times, a co-precipitation was obtained, essentially of cladribine and residual uracil.
[0121] The cladribine thus obtained was recrystallised under reflux conditions at 90° in 20 volumes of a EtOH:H 2 0 mixture, obtaining an anhydrous product with high purity (greater than 99.0%). The quantitative yield of the cladribine after purification and recrystallisation is in the range of 4-5 grams for every litre of reaction mixture, both for the reactions with DMF and for those with DMSO.
[0122] In order to improve the process from an industrial standpoint, a test was carried out in which the bioconversion mixture was brought to pH 12.0 once the reaction had been terminated and the biocatalyst had been separated. Subsequently, the concentration of the solution was carried out by reducing the volume 5-6 times, obtaining precipitation. The precipitate was transferred cold and separated by filtration, resulting in cladribine with a high level of purity.
[0123] In this manner, the first concentration step and subsequent filtration were eliminated, simplifying the process, and a comparable quality product was obtained. | A method for producing cladribine (2-chloro-2′-deoxyadenosine) comprising the steps of:
a) reaction of 2-deoxyuridine with 2-chloroadenine, in the presence of uridine phosphorylase (UPase) and purine nucleoside phosphorylase (PNPase) in an aqueous reaction medium possibly containing up to 40% v/v of an aprotic dipolar solvent, to obtain cladribine dissolved in said reaction medium;
b) isolation of the cladribine by precipitation by means of concentration and alkalinisation of the reaction medium up to pH 11.5-12.5. | 2 |
This application is a continuation of application Ser. No. 08/160,799, filed Dec. 3, 1993, now abandoned.
FIELD OF THE INVENTION
This invention relates to a silver halide photographic emulsion applicable to a silver halide photographic light-sensitive material and, particularly, to a silver halide photographic emulsion having improved in sensitivity and graininess.
BACKGROUND OF THE INVENTION
In recent years, such a photographing apparatus as a camera has been popularized in progress, and a photographing opportunity has also been increased. Accordingly, there has been increased in the demands for making a silver halide photographic light-sensitive material higher in sensitivity and image quality.
One of the dominant factors for making a silver halide photographic light-sensitive material higher in sensitivity and image quality is a silver halide grain. Such a silver halide grain as is aimed at making sensitivity and image quality higher have so far been developed in progress by the art.
However, as has generally been developed so far, there has been a tendency to lower a sensitivity as the grain size of the silver halide grain has been made smaller for improve the image quality, so that there has been a limitation to make both sensitivity and image quality higher.
For making sensitivity and image quality more higher, there have been some techniques for improving a ratio of sensitivity/grain size per one silver halide grain. Among the above-mentioned techniques, the techniques in which a tabular-shaped silver halide grain is used have been described in, for example, Japanese Patent Publication Open to Public Inspection (hereinafter referred to as JP OPI Publication) Nos. 58-111935/1983, 58-111936/1983, 58-111937/1983, 58-111927/1983 and 59-99433/1984. As compared such a tabular-shaped silver halide grain to a regular-crystallized silver halide grain having, for example, octahedron and hexahedron, the surface area of the former tabular-shaped silver halide grain becomes larger than that of the latter when both silver halide grains have each the same volume. Therefore, the former silver halide grain has such an advantage that a more higher sensitivity can be provided, because more sensitizing dyes can be adsorbed to the surface of the former.
JP OPI Publication No. 63-92942/1988 discloses a technique in which a core having a high silver iodide content is contained inside a tabular-shaped silver halide grain; JP OPI Publication No. 63-151618/1988 discloses a technique in which a hexahedral tabular-shaped silver halide grain is used; and JP OPI Publication No. 63-163451/1988 discloses a technique in which a tabular-shaped silver halide grain is so used as to have a ratio of a grain thickness to the farthest distance from and to the twinned crystal surfaces of not higher than 5. These techniques show each the effects on sensitivity and graininess.
As described above, in addition to the technique in which a high sensitivity can be made higher by improving the structure and form of a grain, there is also another known technique in which the movements of photoelectron and positive hole are improved inside a silver halide grain by doping a metal ion in the silver halide grain, so that the photographic characteristics can be renovated.
As for the techniques in which a metal ion is so added as to achieve a high sensitization, JP OPI Publication Nos. 61-160739/1986 and 62-260137/1987 disclose each the techniques in which a polyvalent metal salt such as those of lead and cadmium is added; and JP OPI Publication No. 1-121844/1989 discloses a technique in which an iron compound is doped in a narrow band-gapped layer comprising a grain having a multilayered structure. Besides, each of JP OPI Publication Nos. 2-20852/1990, 2-20853/1990, 2-20854/1990, 2-222653/1990 and 2-224545/1990 discloses the technique in which a polyvalent metal and a novel ligand are used in combination.
SUMMARY OF THE INVENTION
It is an object of the invention to provide a silver halide photographic emulsion capable of providing a silver halide photographic light-sensitive material excellent in a fog-sensitivity relation and in graininess.
Another object of the invention is to provide a silver halide photographic emulsion capable of providing a silver halide photographic light-sensitive material excellent in latent image preservability.
The objects of the invention can be achieved with a silver halide photographic emulsion having the following structure;
(1) A light-sensitive photographic emulsion containing light-sensitive silver halide grains comprising substantially silver bromide and/or silver iodobromide, which also contains at least one kind of indium compound; and
(2) A light-sensitive silver halide photographic emulsion as claimed in claim 1, wherein the light-sensitive silver halide grains thereof are of the core/shell type.
DETAILED DESCRIPTION OF THE INVENTION
The silver halide grains applicable to the invention comprise substantially silver bromide and/or silver iodobromide. The expression, "--substantially comprise silver bromide and/or silver iodobromide--", herein means that it may also contain other silver halides than silver bromide or silver iodobromide, such as silver chloride, provided that the effects of the invention shall not be spoiled. In the case of silver chloride, to be more concrete, the content thereof is preferably not more than 1 mol %.
The silver halide grains to be contained in a silver halide photographic emulsion of the invention may have either such a regular crystal form as a cube, an octahedron and a tetradecahedron, or such an irregular crystal form as the spherical form and a tabular form. For these grains, those having any ratio of {100} plane to {111} plane may be used. And, it is also allowed to use those having a complex of the above-mentioned crystal forms and those having a mixture of various crystal forms. Among them, it is preferable to use twinned crystal silver halide grains having two {111} twin planes parallel to each other.
The term, "a twinned crystal", herein means a silver halide crystal having one or more twinned crystal planes in a grain. The classification of the twinned crystal forms is detailed in, for example, A Report made by Klein and Moisar in "Photographishe Korrespondenz", Vol. 99, p.99 and, ibid., Vol. 100, p. 57.
When making use of tabular-shaped silver halide grains in the invention, it is preferable that an average aspect ratio of the thickness of a tabular-shaped grain to a grain size thereof (hereinafter referred to as an aspect ratio) is to be preferably less than 5, more preferably within the range of not less than 1.1 to less than 4.5 and, particularly not less than 1.2 to less than 4. The above-mentioned average aspect ratio can be obtained by averaging the ratios of the grain sizes of the whole tabular-shaped grains to the thicknesses thereof.
The diameter of a silver halide grain is indicated by the projected area thereof converted into a circular form, (i.e., the diameter of a circle having the same projected area as that of the grain). The diameter thereof is to be preferably within the range of 0.1 to 5.0 μm, more preferably 0.2 to 4.0 μm and, particularly 0.3 to 3.0 μm.
As for the silver halide photographic emulsions relating to the invention, any one of those may be used, such as a polydisperse type emulsion having a relatively wide grain-size distribution and a monodisperse type emulsion having a relatively narrow grain-size distribution. Among them, a monodisperse type emulsion is preferably used.
In a monodisperse type silver halide emulsion an amount of silver halide by weight contained within the range of ±20% of an average grain size r is to be preferably not less than 60% of the whole silver halide grain by weight, more preferably not less than 70% and particularly not less than 80% thereof.
The above-mentioned term, "an average grain size r", is herein defined as a grain size ri obtained when maximizing a product ni×ri 3 wherein ni represents a frequency of grains having a grain size ri (and, the significant figures are three and the figure of the lowest column is rounded).
The term, "a grain size" herein means a diameter obtained when the projected image of a silver halide grain is converted into a circular image having the same area.
The above-mentioned grain size can be obtained in the following manner for example. A subject grain is magnified 10,000 to 70,000 times by an electron microscope; the magnified grain image is photographed; and the printed grain size or the projected area thereof is practically measured, (provided, the number of the subject grains are not less than 1,000 grains at random.)
When a grain size distribution is defined by the following formula,
Grain size distribution(%)
=(Standard deviation/Average grain size)×100
a highly monodisperse type emulsion preferably applicable to the invention has a grain size distribution of not more than 20% and preferably not more than 15%.
The above-mentioned average grain sizes and standard deviations are obtained from the above-defined grain size ri.
In the invention, when making use of silver iodobromide as a silver halide, the silver iodide content thereof is to be within the range of, preferably not less than 0.1 mol % to not more than 15 mol %, more preferably not less than 5 mol % to not more than 12 mol %, and particularly not less than 6 mol % to not more than 10 mol % in terms of an average silver iodide content of the whole silver halide grain.
There shall be no special limitation to the silver halide composition of the silver halide grains relating to the invention. It is therefore allowed that the silver halide composition inside a grain may substantially be uniform, may also be continuously varied, or may be of the so-called core/shell type. For achieving a sensitization effectively, a core/shall type silver halide grain is used. In this case, the grains are to be provided inside with a highly silver iodide containing phase having a silver iodide content of preferably not less than 8 mol %, more preferably within the range of 10 to 45 mol % and particularly 20 to 40 mol %.
In a silver halide grain having a highly silver iodide containing phase inside a grain of the invention, the outermost layer thereof is formed of a silver iodide containing phase having a silver iodide content less than that of the highly silver iodide containing phase. In the low silver iodide containing phase for forming the outermost layer, the silver iodide content thereof is preferably not more than 10 mol %, more preferably not more than 6 mol % and particularly within the range of 0 to 4 mol %.
It is also allowed to make present an interlayer having a different silver iodide content between the outermost layer and the highly silver iodide containing phase. The interlayer is to have a silver iodide content within the range of preferably 10 to 22 mol % and more preferably 12 to 20 mol %. The differences of the silver iodide contents between the outermost layer and the interlayer and between the interlayer and the highly silver iodide containing phase are each preferably not less than 6 mol % and more preferably not less than 10 mol %.
In the above-mentioned embodiment, it is also allowed to make present another silver halide phase in the center of the high silver iodide containing phase inside a grain, between the highly silver iodide containing phase and the interlayer each inside a grain, and/or between the interlayer and the outermost layer.
The volume of the outermost layer is preferably within the range of preferably 4 to 70% of the whole grain and more preferably 10 to 50 mol %. The volume of the highly silver iodide containing phase is preferably within the range of preferably 10 to 80% of the whole grain and more preferably 20 to 50 mol %. The volume of the interlayer is preferably within the range of preferably 5 to 60% of the whole grain and more preferably 20 to 55 mol %.
The above-mentioned phases may be substantially any single phases having a uniform composition, the group consisting of plural phases having uniform compositions each variable stepwise, any continuous phases having the compositions continuously variable in any one of the phases, or the combination of the above-mentioned phases.
From the view points of the grain size distribution and productivity, it is preferred to prepare the silver halide grains applicable to the silver halide photographic emulsions of the invention in the following manner. An aqueous solution containing protective colloid and seed grains are put in a reaction chamber in advance and, if required, silver ions, halogen ions or silver halide fine grains are supplied thereto, and the seed grains are grown up to be crystallized thereby. The seed grains can be prepared in a single-jet method or a controlled double-jet method of which has been well-known in the art. When making use of such a seed grain in the invention, the silver halide thereof is substantially comprised of silver bromide or silver iodobromide.
When making use of the seed grains in the invention, the seed grains may be either of the regularly crystallized forms such as a cube, an octahedron and a tetradecahedron, or of the irregularly crystallized forms such as a spherical form and a tabular form. For these grains, those having any ratio of {100} plane to {111} plane may be used. It is also allowed to use those having a complex of the above-mentioned crystal forms or those having a mixture of variously crystallized grains. Among them, it is preferable to use twinned crystal silver halide grains having two {111} twinned planes parallel to each other.
As for the means for preparing a silver halide photographic emulsion relating to the invention, a variety of methods well-known in the art can be used. To be more concrete, a single-jet method, double-jet method and a triple-jet method, for example, may be used in combination. It is also allowed to use a method for controlling a pAg and a pH so as to meet the silver halide growing rate, in a liquid phase in which silver halide is produced.
A silver halide photographic emulsion of the invention can also be prepared in any one of an acidic method, a neutral method and an ammoniacal method.
In preparing a silver halide photographic emulsion of the invention, halide ions and silver ions may be mixed up at the same time or one of them may also be mixed in the other. It is also allowed that, while taking the critical silver halide crystal growing rate into consideration, halide ions and silver ions are added gradually or at the same time while controlling the pH and pAg thereof in a mixing chamber, so that the silver halide crystals may be grown up. It is further allowed that, in any step for preparing silver halide, the silver halide composition of grains may be varied in a conversion method. It is still further allowed that halide ions and silver ions are formed into silver halide fine grains and the fine grains are supplied to a mixing chamber.
In preparing a silver halide photographic emulsion of the invention, it is allowed to make present a well-known silver halide solvent such as ammonia, thioether and thiourea.
To the silver halide grains to be contained in a silver halide photographic emulsion of the invention, a cadmium salt, a zinc salt, a lead salt, a thallium salt, an iridium salt (including the complex salts thereof), a rhodium salt (including the complex salts thereof) and an iron salt (including the complex salts thereof) may be so added as to contain the above-mentioned metal elements inside and/or on the grain surfaces. It is also allowed that a reduction-sensitization nuclei may be provided inside and/or on the grain surfaces by putting them in a suitable reducible atmosphere.
The silver halide grains to be contained in a silver halide emulsion of the invention may be those capable of forming a latent image mainly on the surfaces thereof or mainly inside thereof.
After completing the growth of silver halide grains, unnecessary soluble salts may be removed from a silver halide photographic emulsion of the invention or may be contained as they are in the emulsion. When removing the salts, the salts may be removed in the method described in, for example, Research Disclosure (hereinafter abbreviated to RD), No. 17643, Paragraph 11.
The indium compounds to be contained in a silver halide photographic emulsion of the invention may be monovalent, divalent or trivalent. Among them, a trivalent one is preferable, because it is readily available and stable.
Besides a halide, an oxide, a sulfide, a nitride and a hydroxide, it is also allowed to use a variety of indium compounds such as a sulfate, a nitrate, an oxalate, a halogenocomplex salt, an organic indium compound and an indium acid salt.
Now, the concrete examples of the indium compounds applicable to the invention will be given below. However, the invention shall not be limited thereto.
______________________________________InCl.sub.3.nH.sub.2 O (NH.sub.4).sub.3.[InF.sub.6 ]InBr.sub.3.nH.sub.2 O K.sub.3 InCl.sub.6.2H.sub.2 OInI.sub.3.nH.sub.2 O (NH.sub.4).sub.2.[InCl.sub.5 (H.sub.2 O)]In.sub.2 O.sub.3 (CH.sub.3).sub.4 NInCl.sub.4In.sub.2 S.sub.3 [C.sub.5 H.sub.5 N.HCl].sub.3 InCl.sub.4InN (NH.sub.4).sub.2 InBr.sub.5.H.sub.2 OIn(OH).sub.3.nH.sub.2 O K.sub.3 InBr.sub.6.2H.sub.2 OIn.sub.2 (SO.sub.4).sub.3.nH.sub.2 O (CH.sub.3).sub.4 NInBr.sub.4In(NO.sub.3).sub.3.3H.sub.2 O InIn.sub.2 (CrO.sub.4).sub.3.6H.sub.2 O)______________________________________
In a silver halide photographic emulsion of the invention, it is allowed to use a method for adding the additive generally well-known in the art to the silver halide photographic emulsion. For example, these compounds are dissolved in advance in a suitable organic solvent typified by an alcohol or in water and the solution thereof is then added in. Also, for a method for dispersing a spectrally sensitizing dye, such a dispersion method as described in, for example, JP Application No. 4-714/1990 can be used. To be more concrete, a metal complex of the invention is added in an amount exceeding the solubility thereof in an aqueous system without substantially having any organic solvent and/or any surfactant, so that the resulting solution is dispersed mechanically in solid fine grains having a grain size of not larger than 1 μm and the resulting dispersion is then added to the silver halide photographic emulsion of the invention.
In the invention, the indium compound may be added at the point of time in the course of carrying out any one of the preparing steps for a silver halide photographic emulsion. However, it may be added preferably within the period from a step for forming grains to the point of time before starting a chemically sensitizing step and more preferably at the point of time before completing the growth of silver halide grains.
For containing an indium compound in a silver halide photographic emulsion of the invention, a solution containing the indium compound is directly added in the silver halide photographic emulsion. When it is added in the course of growing silver halide grains, it is also allowed that the indium compound is added in advance to an aqueous solution containing halide ions, an aqueous solution containing silver ions or a solution containing silver halide fine grains. A solution containing the indium compound may be added instantly or may also be added continuously by making use of any arbitrary function.
In the invention, an indium compound is to be added in an amount within the range of preferably not less than 1.0×10 -8 mols to not more than 1.0×10 -1 mols per mol of silver halide grain used, more preferably not less than 1.0×10 -7 mols to not more than 1.0×10 -2 mol and most preferably not less than 1.0×10 -6 mols to not more than 10×10 -3 mols.
When preparing a silver halide photographic emulsion relating to the invention, the optimum conditions can be selected and, about the conditions other than the above, the well-known processing conditions may be referred to, for example, JP OPI Publication Nos. 61-6643/1986, 61-14630/1986, 61-112142/1986, 62-157024/1987, 62-18556/1987, 63-92942/1988, 63-151618/1988, 63-163451/1988, 63-220238/1988 and 63-311244/1988.
A silver halide photographic emulsion of the invention can be applied preferably to a silver halide color photographic light-sensitive material.
When a color photographic light-sensitive material is prepared by making use of a silver halide photographic emulsion of the invention, the silver halide photographic emulsion having been physically, chemically and spectrally sensitized is to be used. The additives applicable to such a processing step are given in RD Nos. 17643, 18716 and 308119. The pages and paragraphs corresponding to the additives are given will be shown below.
______________________________________ [RD308119] [RD17643] [RD18716]Additive Page Paragraph Page Page______________________________________Chemical 996 III-A 23 648sensitizerSpectral 996 IV-A-A, B, 23-24 648-649sensitizer C, D, H, I, JSupersensitizer 996 IV-A-E, J 23-24 648-649Antifoggant 998 VI 24-25 649Stabilizer 998 VI 24-25 649______________________________________
When a color photographic light-sensitive material is prepared by making use of a silver halide photographic emulsion of the invention, the well-known photographic additives applicable thereto are also given in the above-mentioned RDs. The pages and paragraphs corresponding thereto will be given below.
______________________________________ [RD308119] [RD17643] [RD18716]Additive Page Paragraph Page Page______________________________________Color stain 1002 VII-I 25 650preventiveDye-image stabilizer 1001 VII-J 25Whitening agent 998 V 24UV absorbent 1003 VIII-C, 25-26 XIII-CLight absorbent 1003 VIII 25-26Light scattering 1003 VIIIagentFilter dye 1003 VIII 25-26Binder 1003 IX 26 651Antistatic agent 1006 XIII 27 650Layer hardener 1004 X 26 651Plasticizer 1006 XII 27 650Lubricant 1006 XII 27 650Activator Coating 1005 XI 26-27 650acidMatting agent 1007 XVIDeveloping agent 1011 XX-B(contained in a lightsensitive material)______________________________________
When a color photographic light-sensitive material is prepared by making use of a silver halide photographic emulsion of the invention, a variety of couplers may be used. The typical examples of the couplers are given in the following RDs. The pages and paragraphs corresponding thereto will be given below.
______________________________________ [RD308119] [RD17643]Additive Page Paragraph Paragraph______________________________________Yellow coupler 1001 VII-D VII-C-GMagenta coupler 1001 VII-D VII-C-GCyan coupler 1001 VII-D VII-C-GColored coupler 1002 VII-G VII-GDIR coupler 1001 VII-F VII-GBAR coupler 1002 VII-FOther useful residual 1001 VII-Fgroup-releasingcouplerAlkali-soluble 1001 VII-Ecoupler______________________________________
When a color photographic light-sensitive material is prepared by making use of a silver halide photographic emulsion of the invention, an additive applicable thereto can be added in such a dispersion method as described in, for example, RD 308119, p. 1007, paragpraph XIV.
When a color photographic light-sensitive material is prepared by making use of a silver halide photographic emulsion of the invention, such a support as described in, for example, RD 17643, p. 28, RD 18716, pp. 647-648 and RD 308119, p. 1009, paragraph XVII can be used.
To a color photographic light-sensitive material applied with a silver halide photographic emulsion of the invention, such an auxiliary layer as a filter layer and an interlayer each described in, for example, the foregoing RD 308119, paragraph VII-K may be provided.
A color photographic light-sensitive material applied with a silver halide photographic emulsion of the invention may have various layer arrangements such as a normal layer arrangement, an inverse layer arrangement and a unit layer arrangement each described in, for example, RD 308119, paragraph VII-K.
A silver halide photographic emulsion of the invention can preferably be applied to a variety of color photographic light-sensitive materials typified by a color negative film for general or movie use, a color reversal film for slide or TV use, a color paper, a color positive film and a color reversal paper.
A color photographic light-sensitive material applied with a silver halide photographic emulsion of the invention can be developed in such an ordinary method as described in, for example, the foregoing RD 17643, pp. 28-29, RD 18716, p. 615 and RD 308119, paragraph XIX.
EXAMPLES
Now, the invention will be detailed with reference to the following examples. However, the embodiments of the invention shall not be limited thereto.
EXAMPLE 1
(Preparation of Em-A)
Monodispersed silver iodobromide octahedral grains were prepared by making use of monodispersed silver iodobromide regular crystal seed emulsion (of 0.0775 mols in terms of silver content) having an average size (i.e., a side length converted into a cube having the same volume) of 0.28 μm, a silver iodide content (in a uniform composition) of 2 mol % and a size distribution of 18.9% and the following three kinds of solutions.
______________________________________Solution A1Ossein gelatin 33.9 gA 10% Compound I ethanol solution* 10.0 ccAqueous 28% ammonia solution 51.8 ccWater 3383 ccSolution B1Ossein gelatin 32.9 gPotassium bromide 402.8 gPotassium iodide 1.5 gWater 1471 ccSolution C1Silver nitrate 586.8 gAqueous 28% ammonia solution 478.7 ccWater 1031 cc______________________________________ *Compound I: Sodium polyisopropylene.polyethyleneoxy.disuccinate (that wa also used for preparing EmM)
The silver iodobromide regular crystal seed emulsion was added to Solution A1 and, while keeping the resulting solution at 40° C. and stirring it, Solution B1 was acceleratingly added thereto at the same flow rate by taking 150 minutes. At this time, the pH and pAg thereof were controlled by making use of an aqueous acetic acid solution and an aqueous potassium bromide solution as shown in Table 1. After completing the addition, a desalting treatment was carried out in an ordinary method and 56 g of ossein gelatin was then added. After that, the pH and EAg thereof were adjusted (at 40° C.) to be 6.0 and 100 mV, so that Em-A was prepared. From the result of observing the resulting Em-A through a scanning type electron microscope, Em-A was proved to be comprised of monodispersed octahedral grains (containing iodine of 2 mol %) having an average grain size of 1.0 μm.
TABLE 1______________________________________Amount of 0% → 10% → 100%silver addedpH 9.0 → 9.0 → 8.0pAg 9.7 → 9.7 → 10.5______________________________________
(Preparation of Em-B)
Em-B was prepared in the same manner as in Em-A, except that the following solution was used in place of Solution B1 used for preparing Em-A. From the result of observing Em-B through a scanning electron microscope, Em-B was proved to be comprised of monodispersed octahedral grains (containing iodine of 4.4 mol %) having an average grain size of 1.0 μm. However, in the preparation, the adding rate and the pAg were adjusted a little so as to inhibit the small grain production and to uniform the final grain configuration to be octahedral.
______________________________________Solution B1 for Em-B______________________________________Ossein gelatin 32.9 gPotassium bromide 392.5 gPotassium iodide 25.9 gWater 1470 cc______________________________________
(Preparation of Em-C, D)
Em-C and Em-D were each prepared in the same manner as in Em-A, except that Solution B1 used for preparing Em-A was replaced by Solutions B1-1 and B1-2 as shown in Table 2, respectively.
From the result of observing Em-C and Em-D through a scanning electron microscope, Em-C and Em-D were each proved to be comprised of monodispersed octahedral grains (containing iodine of 4.5 mol % in Em-C and 6 mol % in Em-D) having an average grain size of 1.0 μm, respectively. However, as same as in Em-B, the adding rate and the pAg were adjusted a little so as to inhibit the small grain production and to uniform the final grain configuration to be octahedral.
TABLE 2______________________________________ Solution B1-1 Solution B1-2______________________________________Em-C Ossein gelatin 10.4 g 22.5 gPotassium bromide 116.6 g 275.9 gPotassium iodide 18.0 g 7.9 gWater 462 cc 1008 ccEm-D Ossein gelatin 10.4 g 22.5 gPotassium bromide 110.1 g 275.9 gPotassium iodide 27.0 g 7.9 gWater 462 cc 1008 cc______________________________________
(Preparation of Em-E, Em-F, Em-G, Em-H)
Em-E, Em-F, Em-G and Em-H were each prepared in the same manner as in Em-A, Em-B, Em-C and Em-D, except that lead nitrate was added, in an amount of 1.0×10 -4 mols per mol of silver based on the whole silver content, to Solution A1, respectively.
(Preparation of Em-I, Em-J, Em-K and Em-L)
Em-I, Em-J, Em-K and Em-L were each prepared in the same manner as in Em-E, Em-F, Em-G and Em-H, except that lead nitrate was replaced by indium (III) chloride, respectively.
From the results of observing Em-E through Em-L through a scanning type electron microscope, they were each proved to be monodisperse type octahedral grains having an average grain size of 1.0 μm, respectively.
(Preparation of Emulsion-1)
A part of Em-A was heated up to 50° C. and dissolved. Sensitizing dyes (A) and (B) were added thereto in the amounts of 100 mg and 90 mg per mol of silver halide, respectively. The resulting mixture was then adsorbed for 15 minutes. Further, sodium thiosulfate pentahydrate, chloroauric acid and ammonium thiocyanate were added thereto in the amounts of 3.5×10 -6 mols, 1.0×10 -6 mols and 4.0×10 -4 mols per mol of silver halide, respectively. After the resulting mixture was ripened for 120 minutes, 4-hydroxy-6-methyl- (1,3,3a, 7)-tetrazaindene was added as a stabilizer and was then cooled down and solidified, so that Emulsion-1 was prepared. ##STR1##
Sensitizing dyes (A) and (B) were also used for preparing Emulsion-13.
(Preparation of Emulsion-2 through Emulsion-12)
Emulsion-2 through Emulsion-12 were each prepared in the same manner as in Emulsion-1, except that Em-A was replaced by Em-B through Em-L, respectively.
Preparation of monodisperse emulsion layer coated samples 101 through 112
Coated samples 101 through 112 were each prepared by coating the resulting Emulsion-1 through Emulsion-3 on a subbed triacetyl cellulose support in accordance with the following coating formulas and the resulting coated samples were then dried up.
(Coating formulas)
The following layers were coated in this order on the support.
______________________________________Layer 1: A green-sensitive silverhalide emulsion layerEmulsion . . . An amount of silver 2.5 g/m.sup.2coatedMagenta coupler (M-1) 0.01 mols/mol of AgColored magenta coupler (CM-1) 0.005 mols/mol of AgDIR compound (D-1) 0.0002 mols/mol of AgHBS-I (Tricresyl phosphate, TCP) 0.22 g/m.sup.2Layer 2: A Yellow filter layerEmulsified dispersion of yellowcolloidal silver and 2,5-di-t-octylhydroquinone, and H-I (Sodium 2,4-dichloro-6-hydroxy-s-triazine)______________________________________ M-I ##STR2## CMI ##STR3## D-I ##STR4##
(Evaluation of sensitometric results)
After the resulting coated samples 101 through 112 were each exposed wedgewise to green light, they were processed in the following processing steps. And, the characteristic curves thereof were made out. Then, the fog density, relative sensitivity and RMS graininess of each sample were each obtained. (Wherein the relative sensitivity was indicated by a value relative to the reciprocal of an exposure quantity capable of giving a density of a fog density +0.1; and the RMS graininess was indicated by a value relative to the value of the standard deviation of a density obtained when scanning a dye image having a density of a fog density +0.4 through a microdensitometer having a circular-shaped scanning aperture of 25 μm.)
______________________________________Processing steps (at 38° C.)______________________________________Color developing 2 min. 50 sec.Bleaching 6 min. 30 sec.Washing 3 min. 15 sec.Fixing 6 min. 30 sec.Washing 3 min. 15 sec.Stabilizing 1 min. 30 sec.Drying______________________________________
The composition of the processing solutions used in the processing steps were as follows.
______________________________________(Color developer)4-amino-3-methyl-N-ethyl-N- 4.75 g(β-hydroxyethyl) aniline sulfateSodium sulfite anhydride 4.25 gHydroxylamine 1/2 sulfate 2.0 gPotassium carbonate anhydride 37.5 gSodium bromide 1.3 gTrisodium nitrilotriacetate (monohydrate) 2.5 gPotassium hydroxide 1.0 gAdd water to make 1 literAdjust pH to be 10.0(Bleacher)Iron ammonium ethylenediamine tetraacetate 100.0 gDiammonium ethylenediamine tetraacetate 10.0 gAmmonium bromide 150.0 gGlacial acetic acid 10.0 gAdd water to make 1 literAdjust pH with aqueous ammonia to be 6.0(Fixer)Ammonium thiosulfate 175.0 gSodium sulfite.anhydride 8.5 gSodium metasulfite 2.3 gAdd water to make 1 literAdjust pH with acetic acid to be 6.0(Stabilizer)Formalin (in an aqueous 37% solution) 1.5 ccKonidux (manufactured by Konica Corp.) 7.5 ccAdd water to make 1 liter______________________________________
The results of the evaluation of coated samples 101 through 112 will be shown in Table 3 below.
TABLE 3__________________________________________________________________________ Average Compound added RMSSample AgI Grain structure (in (Amt added per Sensi- graini- Invention/No. content AgI content) mol of Ag) Fog tivity ness Comparison__________________________________________________________________________101 2 mol % 2 mol %/2 mol % -- 0.15 100 100 Comparison102 4.4 mol % 2 mol %/4.5 mol % -- 0.11 81 81 Comparison103 4.5 mol % 2 mol %/10 mol %/2 mol % -- 0.13 142 76 Comparison104 6 mol % 2 mol %/15 mol %/2 mol % -- 0.12 165 72 Comparison105 2 mol % 2 mol %/2 mol % Lead nitrate 0.18 124 127 Comparison (in 1 × 10.sup.-4 mols)106 4.4 mol % 2 mol %/4.5 mol % Lead nitrate 0.12 97 84 Comparison (in 1 × 10.sup.-4 mols)107 4.5 mol % 2 mol %/10 mol %/2 mol % Lead nitrate 0.15 180 86 Comparison (in 1 × 10.sup.-4 mols)108 6 mol % 2 mol %/15 mol %/2 mol % Lead nitrate 0.15 205 84 Comparison (in 1 × 10.sup.-4 mols)109 2 mol % 2 mol %/2 mol % Indium chloride 0.16 122 105 Invention (III) (in 1 × 10.sup.-4 mols)110 4.4 mol % 2 mol %/4.5 mol % Indium chloride 0.12 108 86 Invention (III) (in 1 × 10.sup.-4 mols)111 4.5 mol % 2 mol %/10 mol %/2 mol % Indium chloride 0.13 170 75 Invention (III) (in 1 × 10.sup.-4 mols)112 6 mol % 2 mol %/15 mol %/2 mol % Indium chloride 0.13 215 75 Invention (III) (in 1 × 10.sup.-4 mols)__________________________________________________________________________
As is apparent from the results shown in Table 3, the emulsions each containing an indium compound relating to the invention were proved to be more effective as a means for achieving a sensitization without accompanying any fog increase nor any graininess deterioration. When making use of core/shell type silver halide grains as silver halide grains, it was also proved that much better sensitizing effects can be induced without spoiling any fog prevention and any graininess (in particular, the graininess), by making use of an indium compound.
EXAMPLE-2
(Preparation of Em-M)
Core/shell type silver iodobromide twinned crystal grains having a low aspect ratio were prepared by making use of monodispersed spherical silver bromide twinned crystal grains having an average grain size of 0.3 μm and a grain-size distribution of 16.8% (of which the proportion of two parallel twinned crystals was 89% in number) for serving as the seed grains, and the following solutions.
______________________________________Solution A2______________________________________Ossein gelatin 262.5 gA 10% compound I and ethanol solution 1.5 ccAqueous 28% ammonia solution 528.0 ccAqueous 56% acetic acid solution 795.0 ccAdd water to make 4450 cc______________________________________
An aqueous 3.5N potassium bromide solution containing ossein gelatin in a proportion of 4.0% by weight
Solution C2
An aqueous 3.5N ammoniacal silver nitrate solution, (of which the pH was adjusted to be 9.0 with ammonium nitrate.)
Solution D2
A fine-grained emulsion comprising gelatin of 3% by weight and silver iodide grains (having an average grain size of 0.04 μm)
Solution E2
A fine-grained emulsion comprising gelatin of 3% by weight and silver iodobromide grains (having a silver iodide content of 1 mol % and an average grain size of 0.04 μm)
The procedures for preparing Solutions D2 and E2 were as follows.
(Preparation of Solution D2)
Two liters of an aqueous solution containing 7.06 mols of silver nitrate and 2 liters of an aqueous solution containing 7.06 mols of potassium iodide were added each by taking 10 minutes, respectively, to 5 liters of a 6.0% by weight of ossein gelatin solution containing 0.06 mols of potassium iodide. In the course of forming the fine-grains, the pH was kept at 2.0 by making use of nitric acid and the temperature was kept at 30° C. After completing the grain formation, the pH was adjusted to be 6.0 with an aqueous sodium carbonate solution.
(Preparation of Solution E2)
Two hundred cubic centimeters (200 cc) of an aqueous solution containing 7.06 mols of silver nitrate, and 2 liters of an aqueous solution containing 6.99 mols of potassium bromide and 0.07 mols of potassium iodide were added each by taking 10 minutes, respectively, to 5 liters of a 6.0% by weight ossein gelatin solution containing 0.06 mols of potassium bromide. In the course of forming the fine-grains, the pH was kept at 2.0 by making use of nitric acid and the temperature was kept at 30° C. After completing the grain formation, the pH was adjusted to be 6.0 with an aqueous sodium carbonate solution.
Solution A2 was kept at 70° C., pAg 7.8 and pH 7.2 in a reaction chamber and, while stirring well, a seed emulsion in an amount equivalent to 0.286 mols was added thereto. Thereafter, Solutions B2, C2 and D2 were each acceleratingly added up so that a proportion of silver added could be 78% by taking 140 minutes in a triple-jet method at a flow rate necessary to make the silver halide composition shown in Table 4. Successively, Solution E2 was added in a proportion of 28% equivalent to the amount of silver added, by taking 10 minutes. The resulting emulsion was further ripened for 10 minutes.
In the course of growing the grains, the pH and pAg were controlled to be the values shown in Table 4, by adding an aqueous potassium bromide solution and an aqueous acetic acid solution to the reaction chamber. After completing the grain formation, the grains were washed in an ordinary method and the pH and pAg thereof were adjusted to be 5.8 and 8.06 at 40° C., respectively.
TABLE 4__________________________________________________________________________Silver amount 0.0 9.0 13.0 26.0 33.0 36.0 46.0 78.0 100.0added (%)AgI content 10 → 10 → 30 → 30 → 10 → 10 → 8 ↓ 0 → 0 ↑ 1 → 1(mol %)pH 7.2 → → → → → 7.2 ↓ 6.5 → → → → → → → → → 6.5pAg 7.8 → → → → → 7.8 ↓ 9.4 → → → → → 9.4 → 9.7 → 9.7__________________________________________________________________________ * (→) indicates a constant or continuous variation; (↑), (↓) indicate each an intermittent variation.
From the results of observing the resulting emulsion grains through a scanning type electron microscope, it was confirmed that the resulting emulsion was an low-aspect monodispersed twinned crystal emulsion having a grain size (i .e., a 1.0 μm-diameter converted into that of a sphere) equivalent to the 1.18 μm-diameter of a circle having an average projected area, a grain size distribution of 8 6% , an aspect ratio of 1.3 and a proportion of the grains having two parallel twinned-crystal planes of 86% in number. The resulting emulsion is named Em-M.
(Preparation of Em-N)
Em-N was prepared in the same manner as in Em-M, except that lead nitrate was added, to Solution B2, in an amount of 1.0×10 -4 mols per mol of silver, that corresponded to the standard set by the silver content of the grains already formed.
(Preparation of Em-O)
Em-O was prepared in the same manner as in Em-N, except that lead nitrate was replaced by indium (III) nitrate.
(Preparation of Em-P)
Em-P was prepared in the same manner as in Em-M, except that indium nitrate was added, to Solution E2, in an amount of 1×10 -4 mols per mol of silver, that corresponded to the standard set by the silver content of the grains already formed.
(Preparation of Em-Q)
Em-Q was prepared in the same manner as in Em-M, except that indium nitrate was added, to the halide solution used when preparing Solution E2, in an amount of 1×10 -4 mols per mol of silver, that corresponded to the standard set by the silver content of the grains already formed.
(Preparation of Em-R)
Em-R was prepared in the same manner as in Em-M, except that, after completing the grain growth, indium nitrate was added in an amount equivalent to 1×10 -4 mols per mol of silver and then the emulsion was ripened for 30 minutes before starting a desalting step.
From the results of observing the resulting Em-N through Em-R through a scanning type electron microscope, all of the emulsions were each proved to be a low aspect-ratio monodispersed twinned crystal emulsions having the same grain-size, grain size distribution, aspect ratio, proportion of the grains having two parallel twinned crystal planes as in Em-M.
(Preparation of Emulsion-13)
A part of Em-M was heated up to 50° C. and dissolved. Sensitizing dyes (A) and (B) were each added thereto in the amounts of 110 mg and 100 mg per mol of silver halide, respectively. The resulting mixture was then adsorbed for 15 minutes. Further, sodium thiosulfate pentahydrate, chloroauric acid and ammonium thiocyanate were each added thereto in the amounts of 3.5×10 -6 mols, 1.0×10 -6 mols and 4.0×10 -4 mols per mol of silver halide, respectively. After the resulting mixture was ripened for 120 minutes, 4-hydroxy-6-methyl-(1,3,3a,7)-tetrazaindene was added as a stabilizer and was then cooled down and solidified, so that Emulsion-13 was prepared.
(Preparation of Emulsion-14 through Emulsion-18)
Emulsion-14 through Emulsion-18 were each prepared in the same manner as in Emulsion 13, except that Em-M was replaced by Em-N through Em-R, respectively.
(Preparation of Emulsion-19)
Em-M was heated up to 60° C. and was then dissolved. The pAg of the resulting solution was adjusted to be 9.5. Thereto, indium nitrate in an amount equivalent to 1.0×10 -4 mols per mol of silver was added. After ripening it for 20 minutes, the resulting emulsion was readjusted at 40° C. to be pH=5.8 and pAg=8.06. Thereafter, the resulting emulsion was treated in the same manner as in Emulsion-13, so that Emulsion-19 was prepared.
(Preparation of Emulsion-20)
Emulsion-20 was prepared in the same manner as in Emulsion-19, except that indium nitrate was not added.
(Preparation of Multilayer-coated Samples 201 through 208 and Evaluation of Sensitometric Results therefrom)
Multilayer-coated samples 201 through 208 were each prepared in the following formulas for the multilayer-coated samples by making use of the Emulsion-13 through Emulsion-20 as the silver iodobromide emulsion I for a high-speed green-sensitive layer (Layer 9).
(Multilayer-coating Formula)
In the following multilayer-coating formulas, the amounts of the compositions added to a silver halide photographic light-sensitive material will be indicated in terms of grams per sq. meter of the light-sensitive material, unless otherwise expressly stated. The silver and silver halides used therein will be indicated in terms of the silver contents thereof. The sensitizing dyes will be indicated in terms of mol numbers per mol of the silver halides used.
______________________________________Layer 1: An antihalation layerBlack colloidal silver 0.16UV absorbent (UV-1) 0.20High-boiling organic solvent (Oil-1) 0.16Gelatin 1.23Layer 2: An interlayerHigh-boiling organic solvent (Oil-2) 0.17Gelatin 1.27Layer 3: A low-speed red-sensitiveA silver iodobromide emulsion 0.50(having an average grain-size of0.38 μm and a silver iodide contentof 8.0 mol %)A silver iodobromide emulsion 0.21(having an average grain-size of0.27 μm and a silver iodide contentof 2.0 mol %)Sensitizing dye (SD-1) 2.8 × 10.sup.-4Sensitizing dye (SD-2) 1.9 × 10.sup.-4Sensitizing dye (SD-3) 1.9 × 10.sup.-5Sensitizing dye (SD-4) 1.0 × 10.sup.-4Cyan coupler (C-1) 0.48Cyan coupler (C-2) 0.14Colored cyan coupler (CC-1) 0.021DIR compound (D-1) 0.020High-boiling solvent (Oil-1) 0.53Gelatin 1.30Layer 4: A medium-speed red-sensitive layerA silver iodobromide emulsion 0.62(having an average grain-size of0.52 μm and a silver iodide contentof 8.0 mol %)A silver iodobromide emulsion 0.27(having an average grain-size of0.38 μm and a silver iodide contentof 8.0 mol %)Sensitizing dye (SD-1) 2.3 × 10.sup.-4Sensitizing dye (SD-2) 1.2 × 10.sup.-4Sensitizing dye (SD-3) 1.6 × 10.sup.-5Sensitizing dye (SD-4) 1.2 × 10.sup.-4Cyan coupler (C-1) 0.15Cyan coupler (C-2) 0.18Colored cyan coupler (CC-1) 0.030DIR compound (D-1) 0.013High-boiling solvent (Oil-1) 0.30Gelatin 0.93Layer 5: A high-speed red-sensitive layerA silver iodobromide emulsion 0.27(having an average grain-size of1.00 μm and a silver iodide contentof 8.0 mol %)Sensitizing dye (SD-1) 1.3 × 10.sup.-4Sensitizing dye (SD-2) 1.3 × 10.sup.-4Sensitizing dye (SD-3) 1.6 × 10.sup.-5Cyan coupler (C-2) 0.12Colored cyan coupler (CC-1) 0.013High-boiling solvent (Oil-1) 0.14Gelatin 0.91Layer 6: An interlayerHigh-boiling organic solvent (Oil-2) 0.11Gelatin 0.80Layer 7: A low-speed green-sensitive layerA silver iodobromide emulsion 0.61(having an average grain-size of0.38 μm and a silver iodide contentof 8.0 mol %)A silver iodobromide emulsion 0.20(having an average grain-size of0.27 μm and a silver iodide contentof 2.0 mol %)Sensitizing dye (SD-4) 7.4 × 10.sup.-5Sensitizing dye (SD-5) 6.6 × 10.sup.-4Magenta coupler (M-1) 0.18Magenta coupler (M-2) 0.44Colored cyan coupler (CM-1) 0.12High-boiling solvent (Oil-2) 0.75Gelatin 1.95Layer 8: A medium-speed green-sensitive layerA silver iodobromide emulsion 0.87(having an average grain-size of0.59 μm and a silver iodide contentof 8.0 mol %)Sensitizing dye (SD-6) 2.4 × 10.sup.-4Sensitizing dye (SD-7) 2.4 × 10.sup.-4Magenta coupler (M-1) 0.058Magenta coupler (M-2) 0.13Colored cyan coupler (CM-1) 0.070DIR compound (D-2) 0.025DIR compound (D-3) 0.002High-boiling solvent (Oil-2) 0.50Gelatin 1.00Layer 9: A high-speed green-sensitive layerSilver iodobromide emulsion I 1.27Magenta coupler (M-2) 0.084Magenta coupler (M-3) 0.064Colored cyan coupler (CM-1) 0.012High-boiling solvent (Oil-1) 0.27High-boiling solvent (Oil-2) 0.012Gelatin 1.00Layer 10: A yellow filter layerYellow colloidal silver 0.08Color-stain inhibitor (SC-2) 0.15Formalin scavenger (HS-1) 0.20High-boiling solvent (Oil-2) 0.19Gelatin 1.10Layer 11: An interlayerFormalin scavenger (HS-1) 0.20Gelatin 0.60Layer 12: A low-speed blue-sensitive layerA silver iodobromide emulsion 0.22(having an average grain-size of0.38 μm and a silver iodide contentof 3.0 mol %)A silver iodobromide emulsion 0.03(having an average grain-size of0.27 μm and a silver iodide contentof 2.0 mol %)Sensitizing dye (SD-8) 4.9 × 10.sup.-4Yellow coupler (Y-1) 0.75DIR compound (D-1) 0.010High-boiling solvent (Oil-2) 0.30Gelatin 1.20Layer 13: A medium-speed blue-sensitive layerA silver iodobromide emulsion 0.30(having an average grain-size of0.59 μm and a silver iodide contentof 8.0 mol %)Sensitizing dye (SD-8) 1.6 × 10.sup.-4Sensitizing dye (SD-9) 7.2 × 10.sup.-5Yellow coupler (Y-1) 0.10DIR compound (D-1) 0.010High-boiling solvent (Oil-2) 0.046Gelatin 0.47Layer 14: A high-speed blue-sensitive layerA silver iodobromide emulsion 0.85(having an average grain-size of1.00 μm and a silver iodide contentof 10.0 mol %)Sensitizing dye (SD-8) 7.3 × 10.sup.-5Sensitizing dye (SD-9) 2.8 × 10.sup.-5Yellow coupler (Y-1) 0.11High-boiling solvent (Oil-2) 0.046Gelatin 0.80Layer 15: Protective layer 1A silver iodobromide emulsion 0.40(having an average grain-size of0.08 μm and a silver iodide contentof 1.0 mol %)UV absorbent (UV-1) 0.065UV absorbent (UV-2) 0.10High-boiling solvent (Oil-1) 0.07High-boiling solvent (Oil-3) 0.07Formalin scavenger (HS-1) 0.40Gelatin 1.31Layer 16: Portective layer 2An alkali-soluble matting agent 0.15(having an average particle size of 2 μm)Polymethyl methacrylate 0.04(having an average particle size of 3 μm)Lubricant (WAX-1) 0.04Gelatin 0.55______________________________________
Besides the above-given compositions, coating aids Su-1 and Su-2, a viscosity controller, layer hardeners H-1 and H-2, stabilizer ST-1, antifoggants AF-1 and AF-2 having a weight average molecular weights of 10,000 and 1,100,000 respectively, and antiseptic D1-1 were each added, provided that D1-1 was added in an amount of 9.4 mg/m 2 .
The chemical structures of the compounds used in the samples will be shown below. ##STR5##
The resulting multilayer -coated samples 201 through 208 were each cut into strips. A part of each stripped sample were exposed wedgewise to white light (for an exposure time of 1/100th sec.) and then the fog and sensitivity thereof were evaluated. Another part of each sample were exposed wedgewise to light for an exposure time of 1/100th sec.) and, after storing in the conditions of 55° C. and 20% RH for 2 days, they were developed, and the preservability of the latent images were evaluated.
The development process was carried out by making use of the processing solutions having the same formulas as in Example-1 and by taking the following processing time.
______________________________________Processing steps (at 38° C.)______________________________________Color developing 3 min. 15 sec.Bleaching 6 min. 30 sec.Washing 3 min. 15 sec.Fixing 6 min. 30 sec.Washing 3 min. 15 sec.Stabilizing 1 min. 30 sec.Drying______________________________________
Table 5 shows the results of the evaluation on the fog production, sensitivity, RMS graininess and latent image preservability of each green-sensitive layer.
TABLE 5__________________________________________________________________________ Latent Compound added imageSample (Amt added per Sensi- Graini- preserva- Invention/No. mol of Ag) Where & when added Fog tivity ness bility Comparison__________________________________________________________________________201 -- -- 0.12 100 100 95 Comparison202 Potassium Solution B2 0.15 132 117 135 Comparison ferrocyanide, 1 × 10.sup.-4 mols203 Indium nitrate, Solution B2 0.12 130 102 97 Invention 1 × 10.sup.-4 mols204 Indium nitrate, Solution E2 0.12 125 101 96 Invention 1 × 10.sup.-4 mols205 Indium nitrate, Halide solution in 0.11 133 98 95 Invention 1 × 10.sup.-4 mols preparing Solution E2206 Indium nitrate, Between completion of 0.13 120 100 101 Invention 1 × 10.sup.-4 mols grains and the starting of desalting207 Indium nitrate, Before chemical 0.13 115 105 100 Invention 1 × 10.sup.-4 mols ripening208 -- -- 0.12 96 104 99 Comparison__________________________________________________________________________
Sensitivity of the samples were obtained in terms of the reciprocals of an exposure quantity necessary for giving a density of a fog density+0.1, and each of the values thereof was expressed by a value relative to the sensitivity of Sample 201 obtained when exposing it to light for 1/100th sec., that was regarded as the reference value of 100.
In Table 5, the fog densities were expressed by the difference between the fog density of a sample developed in an ordinary process and the fog density of the sample developed in a developing agent-free process.
Each RMS graininess of the samples was obtained in terms of the standard deviation of the density variations produced when scanning a dye image having a density of a fog density+0.8 through a microdensitometer having an circular scanning aperture of 25 μm, and each of the resulting RMS graininess was expressed by a value relative to the value obtained from Sample 201 that was regarded as the reference value of 100.
Each of the latent image preservability was obtained in terms of a sensitivity obtained after completing a preservation and the sensitivity value was expressed by a value relative to the sensitivity obtained by same-day developing the subject sample, that was regarded as the reference value of 100.
From the results shown in Table 5, it was proved that, also in the evaluation made with the color-negative multilayer-coated sample group, the emulsion containing an indium compound of the invention can be a remarkably effective means for achieving a high sensitization without inducing any fog-increase nor graininess deterioration. It was also proved that the same sensitization effects as mentioned above can be enjoyed, even when an indium compound of the invention should be added at any time after completing the grain formation but not in the course of forming the grain, for example, even before starting a desalting step or before starting a chemical ripening step.
In the conventional emulsions containing an iron salt (or a lead salt and so forth), there has been such a problem that an excessive sensitivity increase has been observed in a post-exposure preservation. In contrast thereto, the emulsions of the invention were proved to be excellent also in latent image preservability. | Disclosed is a silver halide photographic light-sensitive emulsion comprising silver halide grains, wherein the silver halide constituent of said silver halide grains is substantially composed of at least one constituent selected from silver bromide or silver iodobromide, and said emulsion contains at least one kind of indium compound. | 6 |
FIELD OF THE INVENTION
The present invention relates to a piecing method and a piecing device for piecing a severed spun yarn on the winding package side and the sliver of a spinning machine for drafting a sliver and then winding to a winding package after spinning by a twisting device of such as a pneumatic type.
BACKGROUND OF THE INVENTION
First, the structure of the relevant part of the spinning machine will be described with reference to FIG. 8 .
Referring to FIG. 8, 10 is a draft device, and a back roller 11 , a third roller 12 , a middle roller 13 laid across an apron belt 14 , and a front roller 15 are formed in this order from the upstream side. A sliver S from a first sliver guide 16 on the upstream side of the back roller 11 is drafted in a designated drafting ration between each roller and is supplied to a twisting device 17 . A second sliver guide 16 a is provided between the third roller 12 and the middle roller 13 .
The twisting device 17 comprises a guide hole (fiber introducing hole) 20 for guiding a fiber bundle F drafted in the draft device 10 to a guide member 18 located opposing to the tip of a hollow guide shaft member 25 to be mentioned later on, a spinning nozzle 22 with a nozzle hole 21 for generating whirling air flow in the tip (spinning point) of the hollow guide shaft member 25 to be mentioned later on, a nozzle block 24 for holding the spinning nozzle 22 and forming an air room 23 , the hollow guide shaft member 25 wherein the tip is provided facing the spinning nozzle 22 , and a holding member 26 for closing the air room 23 by joining to the nozzle block 24 , and which holds on the hollow guide shaft member 25 , and separates the hollow guide shaft member 25 with respect to the spinning nozzle 22 during a yarn breakage.
The fiber bundle F drafted by the draft device 10 is guided along the guide member 18 from the guide hole 20 , and then enters inside the hollow guide shaft member 25 . The end of the fiber, the tip of which is released from the nip at the front roller 15 at the time being, is whirled by the whirling flow injected from the nozzle hole 21 , is wound by reversing on the tip section of the hollow guide shaft member 25 , and is sucked in while winding onto the fiber entering the hollow guide shaft member 25 , to be a spun yarn Y like a true twist of which the most part of the fiber is to be a wrapping fiber. Moreover, the spun yarn Y is wound to the winding package (not shown in the drawings) by passing between a delivery roller 28 and a nip roller 29 contacting with the delivery roller 28 which compose the yarn feeding device on the downstream side of the twisting device 17 .
Between the draft device 10 and the twisting device 17 , an air shower tube 32 for blowing pressurized air to the sliver S during piecing, and a suction pipe 34 for holding the spun yarn at the winding package side and sucking the fiber blown off by the pressurized air from the air shower tube 32 , are provided.
Next, the conventional piecing operation after the yarn breakage will be described in reference to FIG. 9 through FIG. 10 .
When yarn breakage occurs, the back roller 11 and the third roller 12 which are a part of the draft rollers composing the draft device 10 are stopped, and the middle roller 13 and the front roller 15 , which are on the downstream side are maintained in a driving state. At that time, the yarn feeding by the delivery roller 28 and the nip roller 29 is also maintained at a driving state for a while. As a result, as shown in FIG. 9, the sliver S is broken by the driving middle roller 13 , and the sliver S stops with the tip section Sa positioned between the third roller 12 and the middle roller 13 . At this time, the tip section Sa of the sliver S is held by the second sliver guide 16 a.
Following the stopping of a part of the draft rollers of the draft device 10 , the driving (compressed air injection from the nozzle hole 21 ) of the twisting device 17 is stopped while the hollow guide shaft member 25 is transferred to a state in which it is separated from the nozzle block 24 . Under such condition, preceding the piecing operation, the nip roller 29 is separated from the delivery roller 28 and the yarn feeding is stopped. Subsequently, the spun yarn Y at the winding package side is held by a yarn feeding roller 30 which comprises the yarn delivering member, and is fed back to the yarn discharging side of the twisting device 17 by being passed through the nip roller 29 and the delivery roller 28 . Then, by the rotation of the yarn feeding roller 30 , the spun yarn Y is fed toward the draft device 10 , and in cooperation with the air flow (not shown in the drawings) toward the fiber bundle inlet of the guide hole 20 , as a leading yarn Y (parent yarn), is passed through, in the opposite direction of the spinning direction inside the hollow guide shaft member 25 .
Furthermore, by rotating the yarn feeding roller 30 , the yarn tip of the leading yarn Y, projects from the guide hole 20 of the spinning nozzle 22 in cooperation with the air flow toward the fiber bundle inlet mentioned above, and the yarn tip of the leading yarn Y is held by being sucked by the suction pipe 34 provided between the spinning nozzle 22 and the front roller 15 . Then, as shown in FIG. 10, the holding member 26 is joined with the nozzle block 24 again.
Then, the draft rollers (back roller 11 and third roller 12 ), which were stopped, are redriven, the sliver S is passed through the middle roller 13 and the front roller 15 and is delivered to the downstream side. At that time, the tip section of the sliver S is blown off by the pressurized air from the air shower tube 32 and is sucked and eliminated by the suction pipe 34 so that the guide hole 20 of the spinning nozzle 22 is not blocked.
Under the state in which the leading yarn (spun yarn) Y is held as in the manner stated above, the yarn feeding roller 30 is released from the yarn path, and starts running in the winding direction of the leading yarn Y by the nip roller 29 and the delivery roller 28 . After redriving the injection of the whirling air flow from the nozzle hole 21 , by stopping the injection of the pressurized air from the air shower tube 32 , the fiber composing the sliver S is wound around the outer periphery of the leading yarn Y, the piecing is carried out and the spinning is recommenced.
However, there were problems in the piecing method and the piecing device of aforementioned conventional spinning machine as to be described in the following.
That is, since the distance between the air shower tube 32 and the sliver S is long, and the pressurized air hits the front roller 15 of the draft device 10 , it was inefficient and there were cases in which the joint is bunched up together without the fiber, of which the fiber length is long and unlikely to be blown off to be eliminated completely.
Moreover, after stopping the injection of the pressurized air from the air shower tube 32 , since the fiber amount of the sliver S, which is to enter the guide hole 20 of the spinning nozzle 22 for piecing, is the normal fiber amount; in other words, a fiber amount that is the same as the leading yarn Y, the joint thickness will be theoretically 2 times that of the leading yarn Y in cross section, and in diameter, 1.4 times.
These were the yarn defects, and there was a problem in that the quality of the spun yarn as a product decreases.
The object of the present invention is to solve the problems mentioned above, and to provide a piecing method and a piecing device of a spinning machine capable of blowing off the sliver effectively during piecing and controlling the joint thickness.
SUMMARY OF THE INVENTION
The present invention to achieve the object mentioned above, relates to a piecing method for blowing pressurized air to a sliver and sucking and guiding by a suction pipe provided between a twisting device and a draft device to carry out piecing to a leading yarn fed back to the twisting device and the sliver from the draft device, wherein the pressurized air is made to be blown in an opposing direction toward the sliver from the periphery of a spinning nozzle of the twisting device.
If constructed in accordance with the invention, the pressurized air can be blown from a position close to the sliver, and since there are no obstacles for the blowing, the sliver can be blown off efficiently.
Moreover, the pressurized air can be set to be weaker than the suction force of the spinning nozzle of the twisting device during piecing, and the joint thickness achieved by the piecing can be controlled to be a desired thickness by selecting the blowing time of the pressurized air.
Accordingly, the joint thickness can be controlled by blowing off and eliminating a part of the fiber of the sliver to enter the guide hole of the spinning nozzle.
Moreover, the present invention relates to a piecing method for blowing pressurized air to a sliver and sucking and guiding by a suction pipe provided between a twisting device and a draft device to carry out piecing of a leading yarn fed back to the twisting device and the sliver from the draft device, wherein an air nozzle for blowing pressurized air in a direction opposing the sliver delivered from the draft device is provided around a spinning nozzle of the twisting device.
BRIEF DESCRIPTION OF THE DRAWINGS
ü@ü@ FIG. 1 is detailed partial sectional view showing a spinning nozzle and an air nozzle of a piecing device according to an embodiment of the present invention.
FIG. 2 is a front view of the spinning nozzle and the air nozzle of the piecing device according to an embodiment of the present invention.
FIG. 3 is a diagram showing the entire spinning machine according to an embodiment of the present invention.
FIG. 4 is a time chart showing the driving timing of each device during piecing.
FIG. 5 is a diagram showing the relationship between the stop timing of the air nozzle and the joint thickness.
FIG. 6 is a diagram showing the relationship between the length of the pipe from a valve to the air nozzle and the port number of the valve, and the decrease in the pressure of the air after the stopping of the air nozzle.
FIG. 7 is a diagram showing another embodiment of the air nozzle.
FIG. 8 is a diagram showing the whole structure of the conventional spinning machine.
FIG. 9 is a diagram showing the conventional piecing device and the method of the same.
FIG. 10 is a diagram showing the conventional piecing device in another condition of the method of the same.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
A preferred embodiment according to the present invention will now be described in reference to the accompanying drawings.
The entire structure of the spinning machine according to an embodiment of the present invention is the same as the spinning machine illustrated in FIG. 8 . Therefore, for the same members, the same reference numbers will be used and the description will be abbreviated.
The main point of the present invention is that an air nozzle 40 for injecting compressed air to the sliver S during piecing and for sucking the blown sliver into the suction pipe 34 is provided around the tip section of the spinning nozzle 22 of the twisting device 17 .
As shown in FIG. 1 and FIG. 2, the air nozzle 40 according to the embodiment of the present invention is formed in a circular form about the entire periphery of the periclinal of the spinning nozzle 22 . In addition, an air passageway 41 connected to a compressed air supplying means which is not shown in the drawings, and an air manifold unit 42 for storing the pressurized air supplied to the air passage way 41 temporarily are connected to the air nozzle 40 . The air manifold unit 42 is formed in a circular form along the entire periphery of the periclinal of the spinning nozzle 22 , in the same manner as the air nozzle 40 .
The pressurized air supplied into the air passage way 41 from the compressed air supplying means is stored in the air stocking unit 42 temporarily, and then injected from the air nozzle 40 toward the sliver S delivered from the front roller 15 of a draft device 10 in a direction opposed to the direction of movement of the sliver.
As is evident from the drawings, there are no obstacles between the air nozzle 40 and the sliver S which is delivered from the draft device 10 , and the pressurized air from the air nozzle 40 can be blown reliably to the sliver S. Moreover, compared to the conventional air shower 32 illustrated in FIG. 8, the air nozzle 40 is capable of blowing pressurized air from a position closer to the sliver S.
The piecing operation after the yarn breakage in the spinning machine according to the embodiment of present invention provided with such air nozzle 40 will now be described.
The basic piecing operation is the same as the conventional piecing operation. When a yarn breakage occurs, first, the back roller 11 and the third roller 12 which are part of the draft rollers composing the draft device 10 are stopped while the middle roller 13 and the front roller 15 which are located the downstream side are kept in a driving state. At that time, the yarn delivery by the delivery roller 28 and the nip roller 29 is also maintained in a driving state for awhile. As a result, the sliver S is pulled from the middle roller 13 which is driving, and stops under the condition in which the tip section of the sliver S is located between the third roller 12 and the middle roller 13 . At that time, the tip section of the sliver S is held by the second sliver guide 16 a.
The driving (compressed air injection from the nozzle hole 21 ) of the twisting device 17 is stopped following the stopping of the aforementioned draft rollers of the draft device 10 . Then, the hollow guide shaft member 25 is separated from the nozzle block 24 . Under such state, preceding the piecing operation, the nip roller 29 is separated from the delivery roller 28 and the yarn delivery is stopped. Then, the spun yarn Y on the winding package P side is held by the yarn feeding roller 30 which comprises a yarn delivering member, and is back fed to the yarn discharging side of the twisting device 17 while being passed through the nip roller 29 and the delivery roller 28 . The spun yarn Y is then fed toward the draft device 10 by the rotation of the yarn feeding roller 30 , and in cooperation with an air flow (not shown in the drawings) toward the fiber bundle inlet of the guide hole 20 as a leading yarn, is inserted in the opposite direction of the spinning direction inside the hollow guide shaft member 25 .
Furthermore, by rotating the yarn feeding roller 30 , the yarn end of the leading yarn projects from the guide hole 20 of the spinning nozzle 22 in cooperation with the air flow toward the fiber bundle inlet, and the yarn tip of the leading yarn is sucked by the suction pipe 34 provided between the nozzle 22 and the front roller 15 and is held thereby. Then, the holding member 26 is fit into the nozzle block 24 again and the piecing preparation is completed.
Then, the draft rollers (back roller 11 and third roller 12 ), which were stopped, are redriven, and the sliver S is passed through the middle roller 13 and the front roller 15 and is delivered to the downstream side. At that time, the pressurized air is blew out from the air nozzle 40 provided around the spinning nozzle 22 to oppose toward the sliver S fed from the draft device 10 , the tip section of the sliver S is blown off, sucked into and eliminated by the suction pipe 34 . As a result the fiber is prevented from getting clogged in the guide hole 20 .
Under such state in that the leading yarn (spun yarn) Y is held, the yarn feeding roller 30 is released from the yarn path, and the running in the winding direction of the leading yarn Y by the nip roller 29 and the delivery roller 28 are started, and after the injection of the whirling air flow from the nozzle hole 21 is redriven, by stopping the injection of the pressurized air from the air nozzle 40 , the fiber comprising the sliver S is wound around the leading yarn Y and the piecing is carried out. The spinning operation is then restarted.
FIG. 4 is a time chart showing the driving timing of the draft rollers (back roller 11 and third roller 12 ), the twisting device 17 (compressed air injection from the nozzle hole 21 ), the air nozzle 40 and the nip roller 29 , after the piecing preparation is completed by holding the yarn tip of the leading yarn by the suction pipe 34 . Referring to FIG. 4, the driving timing of each device will be described.
First, when the yarn tip of the leading yarn is held by the suction pipe 34 , the air nozzle 40 is put “ON”, and the pressurized air is blown to the sliver S and the yarn tip is blown off. As a result, the fiber is prevented from being clogged in the guide hole 20 of the spinning nozzle 22 . At that time, the draft rollers 11 , 12 , the twisting device 17 and the nip roller 29 are put “OFF”, and are stopped.
Then, the draft rollers 11 , 12 are put “ON” at time Ta, and the sliver S is delivered to the downstream side through the middle roller 13 and the front roller 15 . At that time, the air nozzle 40 is still put “ON”.
Next, at time Tb, somewhat later than time Ta, the time the draft rollers 11 , 12 are put “ON”, the nip roller 29 is put “ON” and the running of the leading yarn Y in the winding direction by the nip roller 29 and the delivery roller 28 is started.
Then, at time Tc, the twisting device 17 is put “ON” and the piecing is carried out.
Lastly, at time Td, the air nozzle 40 is put “OFF”, and the air inside the air manifold unit 42 is injected gradually from the air nozzle 40 . At time Te, the injection of the compressed air from the air nozzle 40 is stopped completely.
According to the embodiment of the present invention, since the pressurized air is injected to oppose the sliver S which is delivered by the draft device 10 from the periphery of the spinning nozzle 22 , there are no obstacles to air blowing and the operation efficiency is high.
Moreover, compared to the conventional device, since the pressurized air is injected from a position closer to the sliver S, the sliver S can be blown off efficiently, wherein the fiber of which is less prone to be blown off, such as long fiber, can also be blown off reliably.
Furthermore, according to the present invention, by setting the force of the pressurized air from the air nozzle 40 to be weaker than the suction force of the spinning nozzle 22 of the twisting device 17 during piecing, and selecting the blowing time of the pressurized air, the joint thickness produced by the piecing can be controlled to be a desired value.
In other words, by blowing pressurized air from the air nozzle 40 in a direction toward the sliver S from the draft device 10 which is to be inserted into the guide hole 20 of the spinning nozzle 22 , and blowing off and eliminating a part of the fiber composing the sliver S, the joint thickness can be controlled. The force of the pressurized air from the air nozzle 40 was set to be weaker than the suction force of the spinning nozzle 22 , because, when the force of the pressurized air is stronger than the suction force of the spinning nozzle 22 , all of the fiber of the sliver S fed from the draft device 10 is blown off without entering the guide hole 20 .
Next, referring to FIG. 5, the relationship between the stop timing of the air nozzle and the joint thickness will be described.
In the figure, the horizontal line shows the timing for stopping the air nozzle, and the stop timing slows down by going to the right, and shows that the blowing time is long. The vertical line shows the joint thickness, and 1 shows that the thickness is the same as the leading yarn Y.
First, from point (a) to point (b), the stop timing of the air nozzle 40 is fast, and since the blowing of the pressurized air stops before the sliver S reaches the spinning nozzle 22 , the fiber of the sliver S is not blown off at all. Therefore, the amount of fiber of the sliver S entering the spinning nozzle 22 , is to be the normal fiber amount (the same yarn amount as leading yarn Y), and the diameter of the joint thickness will be theoretically 1.4 times that of the leading yarn Y, as in the same manner as the conventional technology.
Then, as the stop timing of the air nozzle 40 is reduced from that of point (b), the joint thickness gradually gets thin since the fiber amount decreases by a part of the fiber of the tip section of the sliver S being blown off by the pressurized air.
Point (d) shows that the joint thickness gets to the ideal thickness which is almost the same as the thickness of the leading yarn Y. The stop timing of the air nozzle 40 at point (d) is the same as the timing in which the tip section of the leading yarn Y enters the guide hole 20 of the spinning nozzle 22 .
From point (d) to point (c), the stop timing of the air nozzle 40 is slow, and the joint thickness from the end section of the leading yarn Y to the back section will be thinner than the thickness of the leading yarn Y.
Furthermore, when the stop timing of the air nozzle 40 slows down and passes over point (e), the piecing cannot be carried out.
Considering various conditions, such as the transferring speed of the leading yarn Y and the sliver S, by setting the stop timing of the air nozzle 40 at point (d), the joint thickness can be made nearer to the thickness of the leading yarn Y, and the quality of the spun yarn as a product can be improved by preventing the generation of yarn defects.
By lengthening the time between the stopping of the air nozzle 40 to the complete stopping of the blowing of the pressurized air, in other words, by softening the decrease in the pressure of the air, the tendency between point (b) through point (c) of FIG. 5 can be softened. The softening in the tendency of point (b) through point (c) has an effect in that the setting of the stop timing of the air nozzle 40 is facilitated.
For softening the decrease in the pressure of the pressurized air, for example, the length of the pipe between the valve (not shown in the drawings) of the air compressing means and the air nozzle 40 can be lengthened, or the number of parts on the valve can be decreased.
Referring to FIG. 6, the relationship between the length of the pipe between the valve (not shown in the drawings) of the air compressing means and the air nozzle 40 , the number of ports in of the valve, and the decrease in the pressure of the air after the stopping of the air nozzle 40 will be described.
In the figure, point P indicates the stop timing of the air nozzle 40 , line 1 indicates the state in which the pipe length is 20 cm and the port number of the valve is 3, line 2 indicates the state in which the pipe length is 20 cm and the port number of the valve is 2, line 3 indicates the state in which the pipe length is 220 cm and the port number of the valve is 3, and line 4 indicates the state in which the pipe length is 220 cm and the port number of the valve is 2.
As is evident from the figure, when lengthening the pipe length, the decrease in the pressure of the pressurized air softens since the pipe serves as a tank and suppresses the decrease in the pressure. Moreover, by decreasing the port number of the valve, the decrease in the pressure of the pressurized air softens since when the port number of the valve is large, the pressurized air leaks from the port and the decrease in the pressure becomes intense. Thus, by decreasing the port number of the valve, the pressurized air leaking from the port can be prevented.
The air manifold unit 42 shown in FIG. 1 and FIG. 2 is provided to soften the decrease in the pressure of the pressurized air. Therefore, the present invention is not to be limited to the embodiments illustrated in the drawings and the air manifold unit 42 is not required to be provided.
Moreover, referring to FIG. 1 and FIG. 2, it was described that the air nozzle 40 is to be provided in a circular form about the entire periphery of the spinning nozzle 22 , however, the present invention is not to be limited to this configuration, and for example, as shown in FIG. 7, a plurality of air nozzles 40 ′ can be provided around the spinning nozzle 22 .
According to the present invention described above, the following beneficial effects can be expected.
Since the pressurized air can be blown toward the sliver efficiently and reliably, the sliver can be blown off completely, and the generation of yarn defects can be prevented.
By controlling the joint thickness, the joint thickness can be made to be closer to that of the thickness of the leading yarn.
Since the distance from the air nozzle to the sliver is close, the pressure control of the pressurized air blown is easy. | The object of the present invention is to provide a piecing method and a piecing device of a spinning machine capable of blowing off the sliver effectively during piecing and controlling the joint thickness. Accordingly, a means is provided for sucking by guiding to the suction pipe 34 disposed between the twisting device 17 and the draft device 10 by blowing pressurized air to the sliver S so as to carry out piecing of the leading yarn Y fed back to the twisting device 17 and the sliver S from the draft device 10. The pressurized air is blown from the periphery of the spinning nozzle 22 of the twisting device 17 in opposition toward the sliver from the draft device. | 3 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to an input circuit of a memory device, and more particularly to an input circuit for a memory device, which improves a data processing speed by controlling transmission paths for data having passed through a data input buffer in response to an input of a block address.
[0003] 2. Description of the Prior Art
[0004] The data processing speed of a semiconductor memory device is gradually accelerating. Moreover, with the development of a DDR SDRAM capable of accessing two data in one clock, the data processing speed of the memory device accelerates further. In particular, a processing for input data is one of issues important for improving the data processing speed of the memory device.
[0005] FIG. 1 is a block diagram showing the data input circuit of a conventional memory device. Specifically, the memory device disclosed in the present specification denotes a DDR SDRAM, a DDR 2 SDRAM (next generation memory device), etc.
[0006] As shown in FIG. 1 , the conventional data input circuit includes data buffers 101 and 102 , an input multiplexer 103 , data bus writers 105 and 106 , block writers 107 and 108 , and an input selection signal generation circuit 104 for controlling the operations of the data bus writers 105 and 106 .
[0007] For convenience of description, FIG. 1 shows only two data buffers 101 and 102 . However, when the memory device has a data input/output structure of ×16, the number of the data buffers is 16. Accordingly, it is noted that 14 data buffers exist in addition to the data buffers 101 and 102 shown in FIG. 1 .
[0008] The basic operation of each element is as follows.
[0009] The data buffers 101 and 102 controlled by a control signal Din clk receive corresponding data D 0 and D 1 respectively, and output data D 0 _ 1 and D 1 13 1 . Herein, the control signal Din clk is a signal (or clock) generated by the number of times of BL/2 after a write command and denotes a signal generated in synchronization with the rising edge of a first DQS signal.
[0010] The input multiplexer 103 is a circuit for determining transmission paths of the data D 0 _ 1 and D 1 _ 1 . Herein, the reason for determining the transmission paths of the data is because the memory device having the data input/output structure of ×16 type may be used in a data input/output structure of ×8 type as the situation requires.
[0011] For instance, when a data pin of the memory device is set to ×16, it is assumed that 16 bit data are applied to the memory device. In such a case, the data Do_ 1 are sent to the data bus writer 105 along a solid line and the data D 1 _ 1 are sent to the data bus writer 106 along a solid line. Other data D 2 _ 1 , . . . , D 15 _ 1 are sent to data bus writers along solid lines.
[0012] In a state in which the data pin of the memory device is set to ×16, if is assumed that 8 bit data are applied to the memory device, 8 used buffers of 16 buffers are necessary and the other 8 buffers are unnecessary.
[0013] Meanwhile, even though the data pass through the data buffers 101 and 102 , it is necessary to determine the data bus writer, to which the data are to be sent, by the input multiplexer 103 . For instance, the data D 0 _ 1 having passed through the data buffer 101 are sent to one of the two data bus writers 105 and 106 by the input multiplexer 103 . Herein, when data having the number of bits smaller than the predetermined number of bits are applied, the input multiplexer 103 includes a function of determining the transmission paths of the data.
[0014] The data bus writers 105 and 106 send the data transmitted from the input multiplexer 103 to global input lines gio 0 and gio 1 . When the memory device operates in ×16 type, the data bus writers send the data transmitted from the input multiplexer to the global input lines. Further, when the memory device operates in ×8 type, it is necessary to maintain the output terminal of a data bus writer, to which data are not inputted, in an initialization state or precharge state.
[0015] The block writers 107 and 108 send the data to memory blocks through local input lines lio 0 and lio 1 . Herein, the memory block signifies an area subdivided in a memory bank and the memory bank includes a plurality of memory blocks.
[0016] The input selection signal generation circuit 104 receives a 2-clock shifted block column address and a control signal clk Din and outputs signals for controlling the operations of the data bus writers 105 and 106 . Herein, the 2-clock shifted block column address is a two-clock delayed signal than an input column address inputted by a write command as shown in FIG. 2 . That is, the 2-clock shifted block column address is an address for selecting the specific block of the memory bank. The control signal clk Din is a clock signal generated by the number of times of BL/2 after a two-clock delay after the write command. That is, as shown in FIG. 2 , the control signal clk Din is a clock signal generated in synchronization with the rising edge of a clock clk at a time point t 3 .
[0017] FIG. 2 is a waveform view illustrating the operation of the circuit of FIG. 1 . In FIG. 2 , the clock clk denotes a clock signal applied to the memory device and the control signal Din clk is a signal for controlling the data buffers 101 and 102 . Further, the data D 0 _ 2 denotes data outputted from the input multiplexer 103 and the control signal clk Din is a two-clock delayed clock signal after the write command. The 2-clock shifted block column address is a signal two-clock delayed than a column address inputted in synchronization with the same clock as the write command input.
[0018] In the operation of the memory device, the input selection signal generation circuit 104 enables the data bus writers 105 and 106 when both the 2-clock shifted block column address and the control signal clk Din are in high level.
[0019] However, in the prior art, after the 2-clock shifted block column address has been generated, the control signal clk Din is generated after a predetermined period of time passes. That is, after the 2-clock shifted block column address has been generated, the control signal clk Din is generated with a predetermined time margin. Therefore, in the prior art, the operation time of the data bus writer is delayed by the time margin, so that a data transmission speed slows.
SUMMARY OF THE INVENTION
[0020] Accordingly, the present invention has been made to solve the above-mentioned problems occurring in the prior art, and it is an object of the present invention to provide an input circuit capable of improving a data processing speed by accelerating the operation time point of a data bus writer.
[0021] It is another object of the present invention to provide an input circuit capable of improving a data processing speed by shifting a block column address inputted in a write command by one clock and using the shifted block column address.
[0022] In order to achieve the above objects, according to one aspect of the present invention, there is provided an input circuit for a memory device operating in synchronism with a clock signal comprising: data buffer part for receiving data applied from an external of the input circuit; input multiplexer part for receiving the data passed through the data buffer part; data bus writer part receiving the data passed through the input multiplexer part and outputting the data to global input/output lines of the memory device; and input selection signal generation circuit outputting a signal to control the operation of the data bus writer part, wherein the output signal of the input selection signal generation circuit is activated when both a first control signal generated after a write command is applied and then the clock signal is toggled n times and a second control signal generated after a write command is applied and then the clock signal is toggled n−1 times are enabled.
[0023] In the present invention, the first control signal is generated in synchronism with a rising edge of the n-th clock signal generated after the write command is applied, and the second control signal is generated in synchronism with a rising edge of the (n−1)-th clock signal generated after the write command is applied.
[0024] In the present invention, the second control signal is generated by shifting by 1tCK a block column address inputted to the memory device when the write command is applied.
[0025] In order to achieve the above objects, according to one aspect of the present invention, there is provided an input circuit for a memory device comprising: 2N data buffers for receiving data applied from an external of the input circuit; N input multiplexers; 2N data bus writers; N block column address shifters; and N input selection signal generation circuits, Wherein each pair of data buffer of the 2N data buffers is connected to each of the N input multiplexers, each of the N input multiplexers is connected to said each pair of data bus writers of the 2N data bus writers, and each of the N input selection signal generation circuits controls an operation of said each pair of data bus writers of the 2N data bus writers.
[0026] In the present invention, the input selection signal generation circuit allows the i th and the i+1 th data bus writer to be enabled in a predetermined case, and the input selection signal generation circuit allows a data bus writer receiving the third data of the i th and the i+1 th data bus writer to be enabled in a predetermined case.
[0027] In order to achieve the above objects, according to one aspect of the present invention, there is provided an input circuit of a memory device comprising: a plurality of data buffers for inputting data applied from outside; an input multiplexer being connected to two or more data buffers, for multiplexing output data of the data buffers; a block column address shifter for outputting a block column address one-clock delayed than a column address; an input selection signal generation circuit for inputting the block column address and a control signal generated in a write operation; and a data bus writer being connected to an output terminal of the input multiplexer, for operating in response to an output signal of the input selection signal generation circuit.
[0028] In the present invention, the data buffers operate in response to an input of a second control signal generated in synchronization with a DQS signal.
[0029] In the present invention, the block column address shifter comprises: a first transmitter for synchronizing an input of an address latched by a clock signal, which is applied from outside, with a first pulse signal generated in a write command or a read command, and transmitting the synchronized signal; a second transmitter for transmitting a signal outputted from the first transmitter in response to an input of an internal clock synchronized with an external clock; a third transmitter for transmitting a signal outputted from the second transmitter in response to an input of a second pulse signal generated after one clock after a write command; a delay unit for delaying a signal outputted from the third transmitter; and an output unit for inputting an optical signal and an output signal of the delay unit and outputting a 1-clock shifted block column address.
[0030] In the present invention, the block column address shifter comprises: a first transmitter for synchronizing an input of an address latched by a clock signal, which is applied from the external, with a first pulse signal generated in a write command or a read command, and transmitting the synchronized signal; a second transmitter for transmitting a signal outputted from the first transmitter in response to an input of an internal clock synchronized with an external clock; a third transmitter for transmitting a signal outputted from the second transmitter in response to an input of a second pulse signal generated after one clock after a write command; a delay unit for delaying a signal outputted from the third transmitter; an output unit for inputting an optical signal and an output signal of the delay unit and outputting a 1-clock shifted block column address; and a fourth transmitter for transmitting an input of the latched address to the third transmitter in response to an input of a third pulse signal generated in a read command.
[0031] In the present invention, the input selection signal generation circuit comprises: a first decoder for inputting a first 1-clock shifted block column address and a first option signal; a second decoder for inputting a second 1-clock shifted block column address and a second option signal; a first output unit for inputting output signals of the first decoder and the second decoder and the control signal and outputting a first driving signal; a second output unit for inputting the first 1-clock shifted block column address, the output signal of the second decoder and the control signal, and outputting a second driving signal; a third output unit for inputting the second 1-clock shifted block column address, the output signal of the first decoder and the control signal, and outputting a third driving signal; and a fourth output unit for inputting the first 1-clock shifted block column address, the second 1-clock shifted block column address and the control signal, and outputting a fourth driving signal.
[0032] In the present invention, the data bus writer comprises: a first data bus writer being connected to a first output terminal of the input multiplexer to output data to a first global input line; and a second data bus writer being connected to a second output terminal of the input multiplexer to output data to a second global input line.
[0033] In the present invention further comprises: a first block writer being connected to the first data bus writer to output data to a first local data line; and a second block writer being connected to the second data bus writer to output data to a second local data line.
BRIEF DESCRIPTION OF THE DRAWINGS
[0034] The above and other objects, features and advantages of the present invention will be more apparent from the following detailed description taken in conjunction with the accompanying drawings, in which:
[0035] FIG. 1 is a block diagram showing the data input circuit of a conventional memory device;
[0036] FIG. 2 is a waveform view illustrating the operation of the circuit of FIG. 1 ;
[0037] FIG. 3 is a block diagram of a data input circuit according to the present invention;
[0038] FIG. 4 is a circuit diagram showing the Yb shifter of FIG. 3 according to one embodiment of the present invention;
[0039] FIG. 5 is a circuit diagram showing the Yb shifter of FIG. 3 according to another embodiment of the present invention;
[0040] FIG. 6 is a circuit diagram showing the input selection signal generation circuit of FIG. 3 according to an embodiment of the present invention; and
[0041] FIG. 7 is a waveform view illustrating the operation of the circuit of FIG. 3 according to the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0042] Hereinafter, a preferred embodiment of the present invention will be described with reference to the accompanying drawings.
[0043] FIG. 3 is a block diagram showing a data input circuit according to the present invention. Hereinafter, a ×16 type in which the number of data buffers is 16 will be described.
[0044] The data input circuit of a memory device according to the present invention includes data buffers 301 and 302 , an input multiplexer 303 , a Yb shifter 309 , an input selection signal generation circuit 304 , data bus writers 305 and 306 , and block writers 307 and 308 . The data buffers 301 and 302 input data D 0 and D 1 applied from the external of the data input circuit, and the input multiplexer 303 is connected to the data buffers 301 and 302 and multiplexes the output data D 0 _ 1 and D 1 _ 1 of the data buffers 301 and 302 . The Yb shifter 309 is a block column address shifter outputting a block column address one-clock delayed than a column address. The input selection signal generation circuit 304 inputs the block column address and a control signal clk Din generated in a write operation. The data bus writers 305 and 306 are connected to the output terminal of the input multiplexer 303 and operate in response to the output signal of the input selection signal generation circuit 304 . The block writers 307 and 308 output the outputs gio 0 and gio 1 of the data bus writers 305 and 306 to local data lines.
[0045] For convenience of description, FIG. 3 shows only two data buffers 301 and 302 . However, since it is assumed that the data input/output structure is the ×16, it is noted that 14 data buffers exist in addition to the data buffers 301 and 302 . The basic structures of the 14 data buffers are identical to those of the data buffers 301 and 302 of FIG. 3 .
[0046] Further, the basic constructions of the data buffers 301 and 302 , the data bus writers 305 and 306 , and the block writers 307 and 308 of FIG. 3 are actually identical to those of the data buffers 101 and 102 , the data bus writers 105 and 106 , and the block writers 107 and 108 of FIG. 1 .
[0047] FIG. 4 is a circuit diagram showing the Yb shifter 309 (the block column address shifter of the data input circuit) according to an embodiment of the present invention.
[0048] The Yb shifter 309 according to the present invention includes a first transmitter 41 , a second transmitter 42 , a third transmitter 43 , a delay unit 44 and an output unit 45 . The first transmitter 41 synchronizes the input of an address ‘eat’ latched by a clock signal, which is applied from the external of the Yb shifter 309 , with a pulse signal cas 6 generated in a write command or a read command, and transmits the synchronized signal. The second transmitter 42 transmits the signal outputted from the first transmitter 41 in response to the input of an internal clock clkp 4 synchronized with an external clock. The third transmitter 43 transmits the signal outputted from the second transmitter 42 in response to the input of a pulse signal cas 6 _wt_lclk generated after one clock after a write command. The delay unit 44 delays the signal outputted from the third transmitter 43 . The output unit 45 inputs an optical signal opt (e.g., a ×16 relating signal in the ×16 type) and the output signal of the delay unit 44 and outputs a 1-clock shifted block column address gay_blcok_wt.
[0049] In the above construction, each of the transmitters 41 to 43 is constructed by a transmission gate and a latch. Further, it is preferred that the delay unit 44 is constructed by a circuit (e.g., an inverter chain) capable of delaying the signal of a node N 1 . Furthermore, the output unit 45 is constructed by a NAND gate for inputting the optical signal opt and the output signal of the delay unit 44 , and an inverter connected to the output terminal of the NAND gate.
[0050] The Yb shifter 309 shown in FIG. 4 has a constructive characteristic in which a result obtained by one-clock shifting the address eat inputted in the write command is transmitted to the node N 1 .
[0051] Meanwhile, the Yb shifter 309 as shown in FIG. 4 is a circuit realized by two-clock shifting an address only in a write operation, in consideration of a case in which a 2-clock shifted block column address inputs an address in both a read operation and a write operation in the prior art. Accordingly, a bus in the read operation must be additionally constructed.
[0052] An embodiment for solving such a problem is shown in FIG. 5 .
[0053] FIG. 5 is a circuit diagram showing an Yb shifter (block column address shifter) according to another embodiment of the present invention.
[0054] Referring to FIG. 5 , the Yb shifter according to another embodiment of the present invention includes a first transmitter 51 , a second transmitter 52 , a third transmitter 53 , a delay unit 54 , an output unit 55 and a fourth transmitter 56 . The first transmitter 51 synchronizes the input of an address ‘eat’ latched by a clock signal, which is applied from the external of the Yb shifter, with a pulse signal cas 6 generated in a write command or a read command, and transmits the synchronized signal. The second transmitter 52 transmits the signal outputted from the first transmitter 51 in response to the input of an internal clock clkp 4 synchronized with an external clock. The third transmitter 53 transmits the signal outputted from the second transmitter 52 in response to the input of a pulse signal cas 6 _wt_lclk generated after one clock after a write command. The delay unit 54 delays the signal outputted from the third transmitter 53 . The output unit 55 inputs an optical signal (e.g., a ×16 relating signal in the ×16 type) opt and the output signal of the delay unit 54 and outputs a 1-clock shifted block column address gay_blcok_wt. The fourth transmitter 56 transmits the input of the address ‘eat’ to the third transmitter 53 in response to an input of a pulse signal cas 6 _rd generated in a read command.
[0055] In the above construction, each of the transmitters 51 , 52 , 53 and 56 is constructed by a transmission gate and a latch (but, the fourth transmitter 56 is constructed by only a transmission gate). Further, it is preferred that the delay unit 54 is constructed by a circuit (e.g., an inverter chain) capable of delaying the signal of a node N 1 . Furthermore, the output unit 55 is constructed by a NAND gate for inputting the optical signal opt and the output signal of the delay unit 44 , and an inverter connected to the output terminal of the NAND gate.
[0056] The Yb shifter as shown in FIG. 5 is realized, thereby solving the problem in that the bus in the read operation must be additionally constructed.
[0057] FIG. 6 is a circuit diagram showing the input selection signal generation circuit 304 according to an embodiment of the present invention. Specifically, FIG. 6 shows the input selection signal generation circuit 304 realized on an assumption that four driving signals are necessary for the two data bus writers 305 and 306 of FIG. 3 .
[0058] Referring to FIG. 6 , the input selection signal generation circuit 304 according to the present invention includes a first decoder 61 , a second decoder 62 , a first output unit 63 , a second output unit 64 , a third output unit 65 and a fourth output unit 66 . The first decoder 61 inputs a 1-clock shifted block column address gay_blcok_wt_ 11 and an option signal ×16b and the second decoder 62 inputs a 1-clock shifted block column address gay_blcok_wt_ 12 and an option signal ×4. The first output unit 63 inputs the output signals of the first decoder 61 and the second decoder 62 and the control signal clk Din and outputs a first driving signal gay_BC_wt_ 0 . The second output unit 64 inputs the 1-clock shifted block column address gay_blcok_wt_ 11 , the output signal of the second decoder 62 , and the control signal clk Din, and outputs a second driving signal gay_BC_wt_ 1 . The third output unit 65 inputs the 1-clock shifted block column address gay_blcok_wt_ 12 , the output signal of the first decoder 61 , and the control signal clk Din, and outputs a third driving signal gay_BC_wt_ 2 . The fourth output unit 66 inputs the 1-clock shifted block column address gay_blcok_wt_ 11 , the 1-clock shifted block column address gay_blcok_wt_ 12 , and the control signal clk Din, and outputs a fourth driving signal gay_BC_wt_ 3 .
[0059] In the construction of FIG. 6 , each of the first decoder 61 and the second decoder 62 is constructed by a NAND gate and each of the output units 63 to 66 is constructed by a NAND gate and an inverter.
[0060] Referring to the construction of FIG. 6 , when the data input/output structure is the ×16 type, since the option signal ×16b is logically in a low level and the option signal ×4 also is logically in a low level, both the 1-clock shifted block column address gay_blcok_wt_ 11 and the 1-clock shifted block column address gay_blcok_wt_ 12 are logically in a high level. Further, the output signals of the first decoder 61 and the second decoder 62 also are logically in a high level. Accordingly, the driving signals gay_BC_wt_ 0 to gay_BC_wt_ 3 operating the data bus writers 305 and 306 of FIG. 3 are logically in a high level, so that all data bus writers are enabled.
[0061] Meanwhile, when the data input/output structure is the ×8 type, since the option signal ×16b is logically in a high level and the option signal ×4 is logically in a low level, both the 1-clock shifted block column address gay_blcok_wt_ 12 and the output signal of the second decoder 62 are logically in a high level. Further, the 1-clock shifted block column address gay_blcok_wt_ 11 and the output signal of the first decoder 61 have values determined according to the input of the address ‘eat’ latched by the clock signal applied from the external of the Yb shifter 309 . Accordingly, one of the second driving signal gay_BC_wt_ 1 and the fourth driving signal gay_BC_wt_ 3 is enabled, and one of the first driving signal gay_BC_wt_ 0 and the third driving signal gay_BC_wt_ 2 is enabled.
[0062] Further, when the data input/output structure is a ×4 type, since the option signal ×16b is logically in a high level and the option signal ×4 is logically in a high level, only one of the first to the fourth driving signal gay_BC_wt_ 0 to gay_BC_wt_ 3 is enabled.
[0063] Hereinafter, the operation of the data input circuit of FIG. 3 according to the present invention will be described in detail with reference to the embodiments shown in FIGS. 4 to 6 .
[0064] First, in the operation of the ×16 type, data applied to each data buffer are applied to each data bus writer along the solid lines of the input multiplexer. Then, the data are applied to the block writer by the control signal clk Din. Accordingly, the basic data transmission path is identical to that of FIG. 1 .
[0065] Next, in the operation of the ×8 type, it is assumed that data are applied to the data buffer 301 and data are not applied to the data buffer 302 . Further, only the data buffer 301 is enabled by a control signal and the data buffer 302 is disabled.
[0066] A first case: the data D 0 _ 1 outputted from the data buffer 301 can be applied to the data bus writer 305 through a path ‘a’ by the input multiplexer 303 . In such a case, the data D 1 _ 2 of an output terminal to which data are not sent maintain a previous state.
[0067] A second case: the data D 0 _ 1 outputted from the data buffer 301 can be applied to the data bus writer 306 through a path ‘b’ by the input multiplexer 303 . In such a case, the data D 0 _ 2 of the output terminal to which the data are not sent maintain the previous state.
[0068] The data bus writers 305 and 306 receive the output signals D 0 _ 1 and D 0 _ 2 of the input multiplexer 303 .
[0069] The Yb shifter 309 (block column address shifter) outputs a 1-clock shifted block column address Yb. Herein, the 1-clock shifted block column address Yb denotes a signal one-clock delayed after a block column address designating the specific block (i.e., memory block) of the memory bank by the write command has been applied.
[0070] The input selection signal generation circuit 304 receives the 1-clock shifted block column address Yb and the control signal clk Din and outputs the signal operating the operations of the data bus writers 305 and 306 . Herein, the control signal clk Din denotes a signal generated in synchronization with a clock signal after two clocks after the write command.
[0071] In the operation of the ×16 type, the input selection signal generation circuit 304 allows the data bus writers 305 and 306 to be enabled.
[0072] In the operation of the ×8 type, the input selection signal generation circuit 304 selectively allows only one of the data bus writers 305 and 306 to be enabled. That is, the input selection signal generation circuit 304 allows only the data bus writer connected to the path (a or b) selected by the input multiplexer 303 to be enabled.
[0073] The operation after the data bus writer is identical to that of FIG. 1 .
[0074] FIG. 7 is a waveform view illustrating the operation of the circuit shown in FIG. 3 according to the present invention.
[0075] As shown in FIGS. 3 and 7 , the input selection signal generation circuit 304 receives the 1-clock shifted block column address Yb and the control signal clk Din and controls the data bus writers.
[0076] As compared to the conventional circuit described in FIGS. 1 and 2 , in the prior art, a predetermined time margin is required until the control signal clk Din is generated after the 2-clock shifted block column address has been generated. Therefore, the data processing speed is delayed.
[0077] However, in the present invention, the 1-clock shifted block column address is used, so that the generation time point of generation of the control signal clk Din may be lo earlier than that of the prior art. That is, in the present invention, even though the control signal clk Din is immediately generated after a two-clock delay after the write command, there occurs no any problem. Therefore, the operation time point of the input selection signal generation circuit 304 can be earlier. In the present invention, the ×16 type, the ×8 type and the ×4 type are described. However, the technical scope of the present invention can be applied to various cases including a ×32 type, etc.
[0078] As described above, in the present invention, a 1-clock shifted block column address is used, so that the operation time point of a data bus writer can be advanced, thereby accelerating the data processing speed. Further, in the present invention, a design in which a control signal clk Din can pass a shortest path can be made.
[0079] The preferred embodiment of the present invention has been described for illustrative purposes, and those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims. | An input circuit for a semiconductor memory device is disclosed. The input circuit controlling transmission paths for data having passed through a data input buffer by using a 1-clock shifted block column address is provided. In particular, a data input apparatus improving a data processing speed by advancing an operation time point of a data bus writer is provided. | 6 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to novel heat-stable polymers comprising imide functions, to a process for the preparation of such polymers, and to various industrial applications thereof, e.g., in the fabrication of laminates.
2. Description of the Prior Art
It is known to this art, according to French Pat. No. 1,555,564, that thermosetting polymers can be obtained by reacting a bis-imide of an unsaturated dicarboxylic acid with a bis-primary diamine. The curing of such polymers under the action of heat provides a certain class of heat-stable resins.
SUMMARY OF THE INVENTION
According to the present invention, novel polymers comprising imide functions have now been developed which possess an improved ageing resistance vis-a-vis the known polymers of related type.
Further advantages of the polymers according to the invention will become apparent from the description which follows.
Briefly, the novel polymers which are the focus of the present invention are characterized as being the reaction product of:
(1) a compound comprising imide functions, which can be either:
(a) an oligo-imide of the structural formula ##STR1## wherein D is a divalent radical selected from the group comprising those of the formula ##STR2## wherein Y and Y', which are identical or different, are each H, CH 3 or Cl and m is equal to 0 or 1, the symbol A is an organic radical of valency n, containing up to 50 carbon atoms, and n is a number equal to at least 1.5 and at most 5; or
(b) (i) a mixture of an oligo-imide of the general formula (I): ##STR3## wherein D, A and n are as defined above, with a polymaine of the general formula (II):
G(NH.sub.2).sub.z (II)
wherein G is an organic radical of valency z and z is an integer equal to at least 2; or
(ii) the product resulting from the reaction between the said oligo-imide (I) and the said polyamine (II); with
(2) an organosilicon compound containing, in its molecule, at least one hydroxyl group bonded to a silicon atom.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The oligo-imides of the present inventions are preferably maleimides of the structural formula: ##STR4## wherein Y', A and n are defined as above.
In the abovementioned formulae (I) and (III), the symbol A can denote an alkylene radical having fewer than 13 carbon atoms, a phenylene or cyclohexylene radical or one of the radicals of the formulae: ##STR5## wherein t represents an integer from 1 to 3. The symbol A can also represent a divalent radical having from 12 to 30 carbon atoms, which consists of phenylene or cyclohexylene radicals joined to one another by a single valence bond or by an inert atom or group, such as --O--, --S--, an alkylene group having from 1 to 3 carbon atoms, --CO--, --SO 2 --, --NR 1 --, --N═N--, --CONH--, --P(O)--R 1 --, --COHN--X--NHCO--, ##STR6## wherein R 1 represents a hydrogen atom, an alkyl radical having from 1 to 4 carbon atoms or a phenyl or cyclohexyl radical and X represents an alkylene radical having fewer than 13 carbon atoms. Moreover, the various phenylene or cyclohexylene radicals can be substituted by groups such as CH 3 and OCH 3 , or by a chlorine atom.
The symbol A can also represent a radical which contains up to 50 carbon atoms and possesses from 3 to 5 free valencies. The radical may consist of a naphthalene, pyridine or triazine nucleus, a benzene nucleus which can be substituted by one to three methyl groups, or several benzene nuclei which are joined to one another by an inert atom or group which can be one of those indicated above or also ##STR7##
Finally, the symbol A can represent a linear or branched chain alkyl or alkenyl radical which can contain up to 18 carbon atoms, a cycloalkyl radical containing 5 or 6 carbon atoms in the ring, a mono- or bi-cyclic aryl radical or an alkyl aryl or aralkyl radical, containing up to 18 carbon atoms, or one of the radicals: ##STR8## or a monovalent radical consisting of a phenyl radical and a phenylene radical, which are joined to one another by a single valence bond or by an inert atom or group such as --O--, --S--, an alkylene radical having from 1 to 3 carbon atoms, --CO--, --SO 2 --, --NR 1 --, --N═N--, --CONH--, --COO-- or --COOR 1 , in which R 1 has the meaning indicated above. Moreover, these various radicals can be substituted by atoms, radicals or groups such as --F, --Cl, --CH 3 , --OCH 3 , --OC 2 H 5 , --OH, --NO 2 , --COOH, ##STR9##
It is apparent from the foregoing that the maleimide constituent which is preferably selected for carrying out the present invention can be a specific polymaleimide or a mixture containing maleimides of different functionalities. In the particular case where a mixture comprising a monomaleimide is used, the proportion of the monomaleimide in the mixture is preferably such that the number of maleimide functions provided by the monomaleimide does not represent more than 30% of the total number of maleimide functions employed in the reaction.
The maleimide of the formula (III) is, preferably, a bis-imide such as, for example: N,N'-ethylene-bis-maleimide; N,N'-hexamethylene-bis-maleimide; N,N'-meta-phenylene-bis-maleimide; N,N'-para-phenylene-bis-maleimide; N,N'-4,4'-biphenylene-bis-maleimide; N,N'-4,4'-diphenylmethane-bis-maleimide; N,N'-4,4'-(diphenyl ether)-bis-maleimide; N,N'-4,4'-(diphenyl sulfide)-bis-maleimide; N,N'-4,4'-diphenylsulfone-bis-maleimide; N,N'-4,4'-dicyclohexylmethane-bis-maleimide; N,N'-α,α'-4,4'-dimethylenecyclohexane-bis-maleimide; N,N'-meta-xylylene-bis-maleimide; N,N'-para-xylylene-bis-maleimide; N,N'-4,4'-(1,1-diphenylcyclohexane)-bis-maleimide; N,N'-4,4'-diphenylmethane-bis-chloromaleimide; N,N'-4,4'-(1,1-diphenylpropane)-bis-maleimide; N,N'-4,4'-(1,1,1-triphenylethane)-bis-maleimide; N,N'-4,4'-triphenylmethane-bis-maleimide; N,N'-3,5-triazole-1,2,4-bis-maleimide; N,N'-dodecamethylene-bis-maleimide; N,N'-(2,2,4-trimethylhexamethylene)-bis-maleimide; N,N'-4,4'-diphenylmethane-bis-citraconimide; 1,2-bis-(2-maleimidoethoxy)-ethane; 1,3-bis-(3-maleimidopropoxy)-propane; N,N'-4,4'-benzophenone-bis-maleimide; N,N'-pyridine-2,6-diyl-bis-maleimide; N,N'-naphthylene-1,5-bis-maleimide; N,N'-cyclohexylene-1,4-bis-maleimide; N,N'-5-methylphenylene-1,3-bis-maleimide or N,N'-5-methoxyphenylene-1,3-bis-maleimide.
These bis-imides can be prepared by utilizing those methods described in, for example, U.S. Pat. No. 3,018,290 and British Pat. No. 1,137,592.
The following are specific examples of the monomaleimides within the ambit of the invention: N-phenyl-maleimide; N-phenyl-methylmaleimide; N-phenyl-chloromaleimide; N-p-chlorophenyl-maleimide; N-p-methoxyphenyl-maleimide; N-p-methylphenyl-maleimide; N-p-nitrophenyl-maleimide; N-p-phenoxyphenyl-maleimide; N-p-phenylaminophenyl-maleimide; N-p-phenoxycarbonylphenyl-maleimide; 1-maleimido-4-acetoxysuccinimido-benzene; 4-maleimido-4'-acetoxysuccinimido-diphenylmethane; 4-maleimido-4'-acetoxysuccinimido-diphenyl ether; 4-maleimido-4'-acetamido-diphenyl ether; 2-maleimido-6-acetamido-pyridine; 4-maleimido-4'-acetamido-diphenylmethane and N-p-phenylcarbonylphenyl-maleimide.
These mono-imides can be prepared by utilizing the method described in U.S. Pat. No. 2,444,536 for the preparation of N-aryl-maleimide.
Examples of maleimide (III) are the oligomers comprising imide functions having the structural formula: ##STR10## wherein X represents a number ranging from about 0.1 to 2, the symbol R 2 represents a divalent hydrocarbon radical having from 1 to 8 carbon atoms, which is derived from an aldehyde or ketone of the general formula:
O═R.sub.2
in which the oxygen is bonded to a carbon atom of the radical R 2 , and the symbol D' represents a divalent organic radical possessing from 2 to 24 carbon atoms, the valencies of which are borne by adjacent carbon atoms and which is derived from an internal anhydride of the structural formula: ##STR11## a proportion of at least about 60% of the radicals D' representing a radical of the formula: ##STR12## in which the symbol Y has the meaning given above, whereby the radicals D' which may remain can represent, in particular, an alkylene, cycloalkylene, or carbocyclic or heterocyclic aromatic radical. The preparation of these oligomers comprising imide functions is described in German Patent Application No. 2,230,874.
As regards the polyamine of the general formula G(NH 2 ) z , a bis-primary diamine of the general formula: H 2 N--Q--NH 2 (IV), in which the symbol Q can represent one of the divalent radicals represented by the symbol A, is noted as being preferred.
By way of illustration of the polyamines which are representative of those within the scope of the invention, there are mentioned: 4,4'-diaminodicyclohexylmethane; 1,4-diaminocyclohexane; 2,6-diaminopyridine; meta-phenylenediamine; para-phenylenediamine; 4,4'-diaminodiphenylmethane; 2,2-bis-(4-aminophenyl)-propane; benzidine; 4,4'-diaminodiphenyl ether; 4,4'-diaminodiphenyl sulfide; 4,4'-diaminodiphenylsulfone; bis-(4-aminophenyl)-methylphosphine oxide; bis-(4-aminophenyl)-phenylphosphine oxide; N,N-(4-aminophenyl)-methylamine; 1,5-diaminonaphthalene; meta-xylylenediamine; paraxylylenediamine; 1,1-bis-(para-aminophenyl)-phthalane; hexamethylenediamine; 6,6'-diamino-2,2'-bipyridyl; 4,4'-diaminobenzophenone; 4,4'-diaminoazobenzene; bis-(4-aminophenyl)-phenylmethane; 1,1-bis-(4-aminophenyl)-cyclohexane; 1,1-bis-(4-amino-3-methylphenyl)-cyclohexane; 2,5-bis-(m-aminophenyl)-1,3,4-oxadiazole; 2,5-bis-(p-aminophenyl)-1,3,4-oxadiazole; 2,5-bis-(m-aminophenyl)-thiazolo[4,5-d]thiazole; 5,5'-di-(m-aminophenyl)-bis-(1,3,4-oxadiazolyl-2,2'); 4,4'-bis-(p-aminophenyl)-2,2'-bithiazole; m-bis-[4-(p-aminophenyl)-thiazol-2-yl]-benzene; 2,2'-bis-(m-aminophenyl)-5,5'-bibenzimidazole; 4,4'-diaminobenzanilide; phenyl-4,4'-diaminobenzoate; N,N'-bis-(4-aminobenzoyl)-p-phenylenediamine; 3,5-bis-(m-aminophenyl)-4-phenyl-1,2,4-triazole; 4,4'-[N,N'-bis-(p-aminobenzoyl)-diamino]-diphenylmethane; bis-p-(4-aminophenoxycarbonyl)-benzene; bis-p-(4-aminophenoxy)-benzene; 3,5-diamino-1,2,4-triazole; 1,1-bis-(4-aminophenyl)-1-phenylethane; 3,5-bis-(4-aminophenyl)-pyridine; 1,2,4-triaminobenzene; 1,3,5-triaminobenzene; 2,4,6-triaminotoluene; 2,4,6-triamino-1,3,5-trimethylbenzene; 1,3,7-triaminoaphthalene; 2,4,4'-triaminobiphenyl; 2,4,6-triaminopyridine; 2,4,4'-triaminodiphenyl ether; 2,4,4'-triaminodiphenylmethane; 2,4,4'-triaminodiphenylsulfone; 2,4,4'-triaminobenzophenone; 2,4,4'-triamino-3-methyldiphenylmethane; N,N,N-tris-(4-aminophenyl)-amine; tris-(4-aminophenyl)-methane' 4,4',4"-triaminotriphenyl orthophosphate; tris-(4-aminophenyl)-phosphine oxide; 3,5,4'-triaminobenzanilide; melamine; 3,5,3',5'-tetraaminobenzophenone; 1,2,4,5-tetraaminobenzene; 2,3,6,7-tetraaminonaphthalene; 3,3'-diaminobenzidine; 3,3',4,4'-tetraaminodiphenyl ether; 3,3'4,4'-tetraaminodiphenylmethane; 3,3',4,4'-tetraaminodiphenylsulfone; 3,5-bis-(3,4-diaminophenyl)-pyridine; and the oligomers of the structural formula: ##STR13## in which R 2 and x have the meanings given above. These oligomers with amine groups can be obtained in accordance with known processes, such as those which are described in French Pat. Nos. 1,430,977, 1,481,935 and 1,533,696.
The hydroxylic organosilicon compounds which fall within the scope of the invention are known compounds which correspond to the following general formula (V): ##STR14## wherein R 3 , R 4 , R 5 , R 6 and R 7 , which are identical or different, represent: a hydroxyl group or a group of the type --OR 8 , in which R 8 can be a linear or branched chain alkyl radical having from 1 to 6 carbon atoms or a phenyl radical; a hydrogen atom; a linear or branched chain alkyl radical which has from 1 to 6 carbon atoms and which can be optionally substituted by one or more chlorine or fluorine atoms or by the group --CN; a linear or branched chain alkenyl radical having from 1 to 6 carbon atoms; or a phenyl radical which is optionally substituted by one or more alkyl and/or alkoxy radicals having from 1 to 4 carbon atoms, or by one or more chlorine atoms; and y is an integer or fraction from 0 to 1,000.
For a specific organosilicon compound of the formula (V), y is in reality always an integer. However, as these are compounds of polymeric structure in this case (when y is greater than 1), there is rarely a single compound but most frequently a mixture of compounds of the same chemical structure, which differ in the number of repeating units in the molecule. This results in a mean value of y which can be an integer or a fraction.
The hydroxylic organosilicon compounds of the abovementioned type can be characterized by the ratio of the weight of the hydroxyl groups which they possess to the total weight of their molecule.
The organosilicon compounds which are preferably used for carrying out the present invention are the above-mentioned compounds in which the weight ratio of the hydroxyl groups in the molecule is equal to at least 0.0005 and preferably at least 0.001.
Among the organosilicon compounds belonging to this preferred group, very particularly suitable are compounds of the formula (V) in which: R 3 , R 4 , R 5 and R 6 , which are identical or different, represent linear or branched chain alkyl radicals having 1 to 6 carbon atoms, linear or branched chain alkenyl radicals having 1 to 6 carbon atoms, or phenyl radicals; R 7 represents a hydroxyl group; and y is an integer or fraction from 0 to 250.
These compounds are therefore silanediols when y is equal to 0 or, alternatively, polysiloxanediols when y is greater than 0. For their preparation, reference may be made to the work of W. Noll, Chemistry and Technology of Silicones, (English translation of the German edition of 1968), published by Academic Press of New York.
The organosilicon compounds which are very particularly suitable for use in the present invention are selected from the group comprising: diethylsilanediol; diphenylsilanediol; methylphenylsilanediol; 1,1,3,3-tetramethyldisiloxane-1,3-diol; 1,1-dimethyl-3,3-diphenyldisiloxane-1,3-diol; 1,3-dimethyl-1,3-diphenyldisiloxane-1,3-diol; 1,1,3,3,5,5-hexamethyltrisiloxane-1,5-diol; 1,1,3,3,5,5,7,7-octamethyltetrasiloxane-1,7-diol; 1,1,3,3,5,5,7,7,9,9-decamethylpentasiloxane-1,9-diol; 1,1,3,3,5,5,7,7,9,9,11,11-dodecamethylhexasiloxane-1,11-diol; 1,3,5,7,9-pentamethyl-1,3,5,7,9-pentaphenylpentasiloxane-1,9-diol; and also their corresponding higher homologues.
The hydroxylic organosilicon compounds which are very particularly suitable can also be mixtures of two or more of the above-mentioned compounds. Thus, commercial hydroxylic polysiloxane oils or resins can conveniently be used. These are, in particular, α,ω-dihydroxylic polymethylpolysiloxane oils having from 0.2 to 0.3% by weight of hydroxyl groups (for example, 48 V 500 oil from Rhone-Poulenc) or 10 to 12% by weight of hydroxyl groups (for example 48 V 50 oil from Rhone-Poulenc) or α,ω-dihydroxylic methylphenylpolysiloxane oils or resins having 4.5% to 5% by weight of hydroxyl groups (for example, 50606 oil from Rhone-Poulenc) or from 7.5 to 8.5% by weight of hydroxyl groups (for example, 50305 resin from Rhone-Poulenc). These commercial oils or resins are given by way of example, but others exist which are equally suitable.
For the preparation of the polymers according to the invention, it must be understood that it is possible to use a mixture of oligo-imides as well as a mixture of hydroxylic organosilicon compounds. Likewise, the term polyamine can also denote mixtures of polyamines of the same functionally or, alternatively, mixtures of polyamines of which at least two possess different functionalities. One or more bis-primary diamines are generally used, optionally in combination with one or more polyamines of higher functionality, which can represent up to 50% by weight of the weight of the diamines employed.
In the description of the invention, the term oligo-imide, the term polyamine and ther term hydroxylic organosilicon compound therefore encompass not only each compound of this type but also mixtures of oligo-imides, of polyamines or of hydroxylic organosilicon compounds.
When the polymers according to the invention are prepared from an oligo-imide (I) and a hydroxylic organosilicon compound (V) (hereinafter referred to as variant 1), the amounts of reactants are selected so as to provide the weight ratio: ##EQU1## of between 0.05 and 0.08. Preferably, a weight ratio of between 0.1 and 0.5 is employed.
Another means for defining the relative proportions of oligo-imide and hydroxylic organosilicon compound (in variant 1) consists in indicating the ratio of the number of hydroxyl functions in the organosilicon compound to the number of imide groups in the oligo-imide: ##EQU2## This ratio is generally between 0.0003 and 10 and is preferably between 0.001 and 2.
When the polymers according to the invention are prepared from an oligo-imide (I), a polyamine (II) and a hydroxylic organosilicon compound (V) (hereinafter referred to as variant 2), the amounts of reactants used are such that there is a weight ratio: ##EQU3## of between 0.05 and 0.08. This weight ratio is usually between 0.1 and 0.5.
Alternatively, the relative proportions of the reactants (in variant 2) may be defined in terms of the ratio of their functional groups. Thus, the numerator is the number of hydroxyl functions in the hydroxylic organosilicon compound plus the number of amine functions in the polyamine, and the denominator is the number of imide groups in the oligo-imide: ##EQU4## Generally, this ratio is between 0.1 and 10, and is preferably between 0.2 and 4.
In the case of variant 2, the proportion of the hydroxy functions in the hydroxylic organosilicon compound to the amine functions in the polyamine of variant 2 are such that the ratio ##EQU5## is between 0.005 and 40, and preferably between 0.01 and 10.
The polymers according to the invention can be prepared in bulk by heating the mixture of reactants, at least until a homogeneous liquid is obtained. In the case of variant 1 the mixture consists of an oligo-imide (I), as defined above, and a hydroxylic organosilicon compound (V), as defined above. In the case of variant 2 the mixture consists of an oligo-imide (I), a polyamine (II), as defined above, and a hydroxylic organosilicon compound (V). In the following text, these mixtures will be denoted by the expression "mixture of the reactants". Before heating the mixture of the reactants, it is advantageously homogenized.
The reaction temperature can vary within fairly wide limits, as a function of the nature and the number of reactants present, but, as a general rule, it is between 50° C. and 300° C.
The polymers according to the present invention can also be prepared by heating the mixture of the reactants in an organic diluent which is liquid in at least part of the range of 50°-300° C. thereby forming a solution or suspension of the polymers. Among these diluents, there are mentioned, in particular: aromatic hydrocarbons, such as xylenes and toluene; halogen hydrocarbons, such as chlorobenzenes; ethers, such as dioxane, tetrahydrofuran and dibutyl ether; dimethylformamide; dimethylsulfoxide; N-methylpyrrolidone; N-vinylpyrrolidone; methylglycol; and methyl ethyl ketone.
The solutions or suspensions of polymers can be used as obtained for numerous purposes. The polymers can also be isolated, for example by filtration, after precipitation by means of an organic diluent which is miscible with the solvent used. In this context, a hydrocarbon having a boiling point which does not substantially exceed 120° C. can advantageously be used.
However, the polymers of the present invention can also be prepared in the form of prepolymers (P) having a softening point at a temperature below 250° C. (in general, this softening point is between 50° and 200° C.). The softening point of a polymer is regarded as the approximate temperature at which a glass rod can easily be pushed a few millimeters into the polymer. These polymers can be obtained in bulk by heating the mixture of the reactants, until a homogeneous or pasty product is obtained, at a temperature which is generally between 50° and 200° C. The prepolymers can also be prepared in suspension or in solution, in a diluent which is liquid in at least part of the range 50°-200° C.
It must be noted that, according to a preferred embodiment of the invention, it is possible, in the case of variant 2, to form a preliminary prepolymer (PP) from all or part of the oligo-imide and of the polyamine in the proportion of 1.2 to 5 imide groups per amine function. This preliminary prepolymer (PP), having a softening point which is generally between 50° and 200° C., is then mixed with the hydroxylic organosilicon compound and, if appropriate, with the remaining oligo-imide and polyamine in order to obtain the prepolymer (P).
The prepolymers (P) can be used in the form of a liquid mass, whereby simple hot casting suffices to shape and produce molded articles. It is also possible, after cooling and grinding, to use them in the form of powders which are remarkably suitable for compression-molding operations, optionally in the presence of fillers in the form of powders, spheres, granules, fibers or flakes. In the form of suspensions or solutions, the prepolymers (P) can be used to produce coatings and pre-impregnated intermediate articles of which the reinforcement can consist of fibrous materials based on aluminium silicate or oxide or zirconium silicate or oxide, carbon, graphite, boron, asbestos or glass. These prepolymers (P) can also be used to produce cellular materials after incorporation of a pore-forming agent such as azodicarbonamide.
In a second stage, the prepolymers (P) can be cured by heating up to temperatures which are of the order of 350° C. and generally between 150° and 300° C. A complementary shaping can be carried out during curing, either in vacuo or under pressure above atmospheric pressure. It is also possible for these operations to be consecutive. The curing can be carried out in the presence of a free-radical polymerization initiator, such as lauroyl peroxide or azo-bis-isobutyronitrile, or in the presence of an anionic polymerization catalyst, such as diazabicyclooctane.
The polymers according to the invention are of value in those industrial fields which require materials possessing good mechanical and electrical properties and also a high stability at temperatures of the order of 200° to 300° C.
It will be noted very particularly that the polymers according to the invention possess a higher temperature index than that corresponding to the polymers of the prior art, such as, for example, the polyimides described in French Pat. No. 1,555,564 mentioned above. The temperature index of a material is regarded as the temperature at which it retains, after 20,000 hours, mechanical properties which have a value equal to 50% of the initial value of the said properties.
The new polymers according to the invention are further distinguished by considerably improved properties in what is normally a sensitive area, namely the dimensional and weight stability of the polymers with imide groups in an aqueous medium.
All these advantages, which are in no way limited by the above list, show the great value offered by the polymers described in the present invention.
They can be used in the most diverse forms, such as molded articles, laminates, paints, films, coatings and the like. Their applications in fields as varied as the electrical or mechanical industries and the fields of electrical insulation, heating by radiation, convection or conduction, and impregnated circuits, result from the advantages provided by their properties.
In order to further illustrate the present invention and the advantages thereof, the following specific examples are given, it being understood that same are intended only as illustrative and in nowise limitative.
EXAMPLE 1
A prepolymer comprising imide functions was prepared from a mixture of N,N'-4,4'-diphenylmethane-bis-maleimide and 4,4'-diamino-diphenylmethane, the mixture containing 2.5 imide functions per amine function by heating the mixture of reactants for 20 minutes at 160° C. After cooling, the prepolymer obtained was ground and dissolved in N-methylpyrrolidone (NMP).
Subsequently, 165 g of a methylated, hydroxylated polysiloxane oil containing 0.2% by weight of hydroxyl groups (48 V 500" oil from Rhone-Poulenc), were added to a solution of 655 g of the prepolymer prepared above in 1000 g of N-methylpyrrolidone. A solution (or collodion) containing 55% by weight of NMP and 45% by weight solute (36% by weight of prepolymers comprising imide functions and 9% of hydroxylated polysiloxane) was thus obtained.
This collodion was deposited with a brush on both face surfaces of a glass fabric (a cloth weighing 200 grams per square meter treated with "A 1100 finish" (surface treatment provided the cloth by the fabric manufacturer), so as to provide a weight ratio of glass fabric/(prepolymer comprising imide functions+polysiloxane mixture) equal to 65/35. The collodion was deposited in two passes which were separated by a drying step carried out for 1 minute at 140° C. After the second pass, the drying was carried out for 14 minutes at 140° C. in a very well ventilated oven.
The "prepreg" thus obtained was used to prepare laminates, as follows:
(a) 12-ply laminate (12 layers of prepreg): The plies were heated at 160° C. for 6 minutes and were then compressed for 15 minutes at 160° C. under a pressure of 60 bars and finally compressed for 75 minutes at 180° C. also under a pressure of 60 bars. Baking in a ventilated oven was then carried out for 24 hours at 200° C. The proportion of resin in the laminate was 22.5% by weight;
(b) 40-ply laminate (40 layers of prepreg): The plies were heated for 8 minutes at 160° C. and were then compressed for 15 minutes at 160° C. under a pressure of 60 bars and finally compressed for 75 minutes at 180° C. also under a pressure of 60 bars. Baking was next carried out for 24 hours at 200° C. in a ventilated oven. The proportion of resin in the laminate was 24.6% by weight.
Mechanical properties were determined on the 12-ply laminate and on a control 12-ply laminate, prepared from the same glass fabric but using only the prepolymer comprising imide functions prepared as above (proportion of resin in this control laminate=30.1% by weight), are summarized in the following Table I.
The measurements were carried out at ambient temperature (about 20° C.), after baking, in accordance with ASTM Standard Specification D 790.
TABLE I______________________________________TESTS DETERMINATIONS______________________________________Laminate: 12-ply with the Flexural strength 57.3combination according to (kg/mm.sup.2)the invention Flexural modulus 3,050 (kg/mm.sup.2)Laminate: 12-ply Flexural strength 59.0 (kg/mm.sup.2)Control Flexural modulus 2,682 (kg/mm.sup.2)______________________________________
These same measurements were also carried out at 250° C. as above, and the results thereof are reported in the following Table II:
TABLE II______________________________________ TEST PERIOD DETER- AT 250° C.TESTS MINATIONS 0 h 1000 h 2500 h______________________________________Laminate: 12-ply with the Flexural 24.0 22.3 8.5combination according to strengththe invention (kg/mm.sup.2) Flexural 2,080 2,130 1,520 modulus (kg/mm.sup.2)Laminate: 12-ply Flexural 32.0 26.0 15.9 strength (kg/mm.sup.2)Control Flexural 1,889 1,428 1,268 modulus (kg/mm.sup.2)______________________________________
EXAMPLE 2
655 g of prepolymer comprising imide functions, prepared as in Example 1, were added to a solution of 165 g of diphenylsilanediol (containing 15.7% by weight of hydroxyl groups) in 1,000 g of N-methylpyrrolidone (NMP).
The viscosity of this solution (or collodion) was 0.65 poise and did not change when the collodion was stored for 48 hours at ambient temperature (about 20° C.).
This collodion was deposited with a brush on both face surfaces of a glass fabric (a satin weighing 300 g/m 2 , treated with "A 1100 finish"). The coating was carried out utilizing the formulation 35/65 (35% by weight of resin and 65% by weight of glass fabric) in two passes which were separated by a drying step carried out for 1 minute at 170° C. The total drying time was 16 minutes at 170° C. in a ventilated oven. The prepreg obtained above was used to produce laminates by compression for 1 hour at 180° C. under a pressure of 40 bars, followed by baking for 24 hours at 200° C.
A 21-ply laminate containing a proportion of resin of 32.0%, a 12-ply laminate containing a proportion of resin of 26.5% and an 8-ply laminate containing a proportion of resin of 28.0% were thus prepared.
The mechanical properties were determined on the 12-ply laminate and also on a control 12-ply laminate prepared from the same glass fabric (a satin weighing 300 g/m 2 ) coated using only the prepolymer comprising imide functions (proportion of resin: 28.8% by weight).
The measurements were carried out at 180° C. (ASTM Standard Specification D 790) for various aging times at 180° C. (see Table III below):
TABLE III__________________________________________________________________________ AGING TIME at 180° C. 5,000 10,000 15,000 20,000TESTS DETERMINATIONS 0 hour hours hours hours hours__________________________________________________________________________12-ply laminate Flexural strength 47.5 46.9 37.7 34.4 33.9with combination (kg/mm.sup.2)according to theinvention Flexural modulus 2,440 2,200 2,098 2,094 2,125 (kg/mm.sup.2)12-ply laminate Flexural strength 49.7 48.7 39.8 28.3 18.5 (kg/mm.sup.2)Control Flexural modulus 2,389 2,520 2,346 2,215 2,170 (kg/mm.sup.2)__________________________________________________________________________
The electrical properties were determined on the 8- and 21-ply laminates (see results in Table IV):
TABLE IV______________________________________ After 24 Initial hours inElectrical Properties Measured values water______________________________________Dielectric strength (in kV/mm) 19 17Dielectric constant at 1MHz,ε 5 5Tangent of the loss angle at 4 × 10.sup.-3 5 × 10.sup.-31MHz______________________________________
The behavior of the 21-ply laminate in boiling water was determined by measuring the dimensions and the weight of the sample after residence times of 24 hours, 500 hours, 1,000 hours and 1,500 hours. By way of comparison, a control laminate of the same thickness, prepared only from the prepolymer comprising imide functions on the same support fabric, was subjected to the same tests (Table V):
TABLE V__________________________________________________________________________DIMENSIONAL AND WEIGHT STABILITES(in % variation relative to the initial values)__________________________________________________________________________ After 24 hours After 500 hoursTESTS Δ1 Δw Δt ΔW Δ1 Δw Δt ΔW__________________________________________________________________________21-ply laminatewith the combination +0.028 +0.100 +0.45 +0.47 +0.028 +0.039 +0.45 +1.31according to theinventionControl laminate ofthe same thickness +0.038 +0.079 +0.49 +0.69 +0.155 +0.177 +1.23 +1.79__________________________________________________________________________ After 1,000 hours After 1,500 hoursTESTS Δ1 Δw Δt ΔW Δ1 Δw Δt ΔW__________________________________________________________________________21-ply laminatewith the combination +0.028 +0.039 +0.45 +1.59 +0.028 +0.039 +0.45 +1.74according to theinventionControl laminate ofthe same thickness +0.10 +0.196 +2.71 +2.40__________________________________________________________________________ Δ1 = Variation in % relative to the initial length Δw = Variation in % relative to the initial width Δt = Variation in % relative to the initial thickness ΔW = Variation in % relative to the initial weight
The behavior on exposure to fire, in accordance with UL Standard Specification 94 (of UNDERWRITERS LABORATORIES), described in document BNMP 9750 of the Bureau de Normalisation des Matieres Plastiques, of laminates having a thickness of 0.7 mm and 1.4 mm, prepared as previously indicated in the present example, resulted in a classification of 94 V 1, regardless of the thickness and the conditioning.
EXAMPLE 3
655 g of prepolymer comprising imide functions, prepared in accordance with the method described in Example 1, were added to a solution of 165 g of α,ω-dihydroxylic methylphenylpolysiloxane oil containing 4.8% by weight of hydroxyl functions ("50 606" oil from Rhone-Poulenc) in 1,000 g of N-methylpyrrolidone (NMP).
The viscosity of the collodion thus obtained was 0.56 poise and was stable with time.
This collodion was deposited with a brush on both face surfaces of a glass fabric (a satin weighing 300 g/m 2 , treated with "A 1100 finish"). The coating was carried out by utilizing the formulation 35/65 (35% by weight of resin and 65% by weight of glass fabric) in two passes which were separated by a drying step carried out for 1 minute at 180° C. The final drying was carried out for 9 minutes at 180° C. in a ventilated oven.
12- and 20-ply laminates were produced from the prepeg obtained as above by compression for 1 hour at 180° C. under pressure of 40 bars, followed by baking for 24 hours at 200° C.
A 12-ply laminate containing 26.6% by weight of resin and a 20-ply laminate containing 20.9% by weight of resin were thus prepared.
The mechanical properties were determined on the 12-ply laminate and also on a control laminate prepared from the same glass fabric (a satin weighing 300 g/m 2 ) coated using only the prepolymer comprising imide functions (proportion of resin: 28.8% by weight).
The measurements were carried out at 180° C. (ASTM Standard Specification D 790) for various ageing times at 180° C. (Table VI below):
TABLE VI__________________________________________________________________________ AGEING TIME AT 180° C. DETERMIN- 5,000 10,000 15,000 20,000TESTS ATIONS 0 hour hours hours hours hours__________________________________________________________________________12-ply laminate Flexuralwith combination strength 51.9 47.4 45.7 35.8 33.1according to (kg/mm.sup.2)the invention Flexural modulus 2,694 2,654 2,710 2,608 2,445 (kg/mm.sup.2)12-ply laminate Flexural strength 49.7 48.7 39.8 28.3 18.5 (kg/mm.sup.2)Control Flexural modulus 2,389 2,520 2,346 2,215 2,170 (kg/mm.sup.2)__________________________________________________________________________
Measurements carried out at 200° C. on the 12-ply laminate prepared with the combination according to the invention gave the following initial values (time 0):
Flexural strength at 200° C.: 45.1 kg/mm 2
Flexural modulus at 200° C.: 2,685 kg/mm 2 .
Certain electrical properties were also determined on the 20-ply laminate and a second series of measurements of these properties was then carried out after having left the laminate in water for 24 hours (see Table VII below):
TABLE VII______________________________________ After 24 Initial hours inElectrical properties measured values water______________________________________Dielectric strength (in kV/mm) 21 20Volume resistivity Ω cm 1 × 10.sup.15 2 × 10.sup.14Dielectric constant at 1MHz: ε 5 5Tangent of the loss angle at 1MHz 6.1 × 10.sup.-3 6.9 × 10.sup.-3______________________________________
In boiling water, the stability of the 20-ply laminate prepared above was determined by measuring the dimensions and the weight of the sample after residence times of 24 hours, 1,000 hours and 1,700 hours. By way of comparison, a control laminate of the same thickness was prepared on the same support fabric, but using only the prepolymer comprising imide functions, and was subjected to the same tests (see Table VIII below):
TABLE VIII__________________________________________________________________________DIMENSIONAL AND WEIGHT STABILITES(in % variation relative to the initial values)__________________________________________________________________________ After 24 hours After 500 hoursTESTS Δ1 Δw Δt ΔW Δ1 Δw Δt ΔW__________________________________________________________________________21-ply laminatewith the combination 0 0 0 +0.375 0 0 0 +1.25according to theinventionControl laminate ofthe same thickness +0.09 +0.19 +0.14 +0.63 +0.052 +0.16 +1.24 +1.45__________________________________________________________________________ After 1,000 hours After 1,500 hoursTESTS Δ1 Δw Δt ΔW Δ1 Δw Δt ΔW__________________________________________________________________________21-ply laminatewith the combination +0.015 0 +0.25 +1.55 +0.015 0 +0.25 +1.80according to theinventionControl laminate ofthe same thickness +0.10 +0.26 +2.56 +2.04__________________________________________________________________________ Δ1 = Variation in % relative to the initial length Δw = Variation in % relative to the initial width Δt = Variation in % relative to the initial thickness ΔW = Variation in % relative to the initial weight
EXAMPLE 4
30 g of diphenylsilanediol (containing 15.7% by weight of hydroxyl groups) were added to 70 g of prepolymer comprising imide functions prepared as indicated in Examples 1. The combination of these two powders was intimately mixed.
The mixture obtained was placed in a container which was then introduced into a ventilated oven. The oven was then heated for 45 minutes at 165° C. and then for 24 hours at 200° C.
After cooling, the resulting resin was ground until grains having a diameter of less than 100μ were obtained, and was then subjected to thermogravimetric analysis.
The operating conditions of the thermogravimetric analysis were as follows: balance was SETARAM B 60 type; sweep gas was air with a flow rate of 45 ml/minute; heating rate was 5° C./minute. The test consisted of 40 mg of resin.
The results of the analysis were: the resin did not show any loss in weight up to 282° C.; the temperature corresponding to a loss in weight of 5% was 334° C.; and temperature corresponding to a loss in weight of 10% was 362° C.
The resin can therefore withstand high temperatures without suffering substantial damage.
EXAMPLE 5
20 g of diphenylsilanediol (containing 15.7% by weight of hydroxyl groups) were added to 79.8 g of N,N'-4,4'-diphenylmethane-bis-malemide. The combination of these two powders was mixed in a container equipped with a mechanical stirring system.
The mixture was melted by heating it to a temperature of 145° C. and the heating was then continued at 155°-160° C. for 6 minutes, while the mechanical stirring was continued.
The liquid polymer thus obtained was then placed for 5 minutes in an enclosure in which a reduced pressure of 60 mm of Hg was established. The polymer was subsequently cast into an aluminum mold and then introduced into a ventilated oven preheated to 160° C. The polymer was subjected in the oven to the following baking cycle: 30 minutes at 160° C.; then 30 minutes at 170° C.; then 90 minutes at 180° C.; and finally 24 hours at 200° C.
After cooling, the resulting resin was ground until grains having a diameter of less than 100μ were obtained. The ground resin was then subjected to thermogravimetric analysis which showed the good heat stability exhibited by the resin.
The operating conditions at which the thermogravimetric analysis was carried out are those indicated in Example 4. The results of the analysis were: the resin did not shown any loss in weight of 5% was 386° C.; and the temperature corresponding to a loss in weight of 10% was 402° C.
While the invention has been described in terms of various preferred embodiments, the skilled artisan will appreciate that various modifications, substitutions, omissions and changes may be made without departing from the spirit thereof. Accordingly, it is intended that the scope of the present invention be limited solely by the scope of the following claims. | Novel copolymers are comprised of oligo-imide/hydroxylated organosilicon comonomers, or of oligo-imide/polyamine/hydroxylated organosilicon comonomers. Such copolymers are useful in the production of coatings and a variety of shaped articles, e.g., molded and/or foamed shaped articles, laminates and the like. | 2 |
FIELD OF THE INVENTION
This invention is directed to the field of illumination and in particular to the illumination of floral displays.
BACKGROUND OF THE INVENTION
Flowers and floral arrangements have been used throughout history as gifts and to convey sentiments. A single, long-stemmed rose can be an elegant expression of passion, while an elaborate floral bouquet might be used to celebrate a wedding or the birth of a child. The intricate designs and colorful patterns of flowers make them true objects of beauty. Each flower is unique, having its own particular shape and coloring.
Fresh flowers may also produce a pleasant fragrance that adds to the experience when a flower or bouquet is presented. Since the blossoms of flowering plants are typically short-lived, their transitory nature and short life makes them particularly special. While the visual beauty of these flowers is stunning, it can only be enjoyed when illuminated. This is unfortunate, since many of the locations where flowers are used are in areas of reduced lighting such as restaurants or dance venues.
Many attempts have been made to produce artificial flowers that mimic the beauty of live flowers. Often, thin silk or rayon fabrics are employed to fashion facsimiles of real flowers. The fabric is dyed or painted to resemble real flowers. In an attempt to add interest to these artificial flowers, some have been outfitted with electrically powered lighting devices. Even the best of these fakes however, can not compare with the delicate beauty of real flowers. Illuminated artificial flowers are no exception. It is unlikely that an individual would present his or her prom date with an artificial flower, even if illuminated.
Deng, U.S. application US2004/00885758, discloses a means for lighting artificial flowers employing a small light bulb or light emitting diode. In this embodiment a flower is assembled around the lighting means. When power is applied to the lamp, the artificial flower illuminates from within.
Harris, U.S. Pat. No. 5,063,485, discloses an illuminated artificial flower arrangement that includes a container with an electrical terminal block being mounted on the stem support.
Von Kohorn, U.S. Pat. No. 4,616,304, teaches a device for displaying three-dimensional objects to be centripetally viewed such as flower arrangements. The light source is contained in a lower cavity while the flowers are contained in an upper cavity.
Jansen, U.S. Pat. No. 4,646,209, discloses an illuminated standing support for plants which comprises a translucent material, a plant, a flower or other recipient provided in the upper part of said support and a light source installed on said holder for illumination of translucent support.
Kurita et al., U.S. Pat. No. 4,399,439, discloses an illuminated artificial flower ornament in which a miniature bulb is located in the peduncle part of an artificial flower.
Fernandez, U.S. Pat. No. 4,125,462, discloses a method for making a translucent optical diffuser for a flower lamp. A method of chemically treating animal bladders to convert them into diffusers is also disclosed.
Sanford, U.S. Pat. No. 6,076,940, discloses a planter light accessory for illuminating a plant within a container. A cylindrical housing contains a light source that is mounted on the edge of the cylindrical housing for illuminating the plant.
Huang, U.S. Pat. No. 5,947,582, discloses a flower shaped lamp including a mount for an artificial flower. A tubular stem of the artificial flower contains an electric wire that is connected to a bulb that is mounted on the artificial flower.
Kuo, U.S. Pat. No. 5,508,901, discloses a multicolored light-emitting flower decoration that employs chemiluminescent reagents to produce light.
Von Kohorn, U.S. Pat. No. 4,626,968, discloses a device and a system for indirect, substantially glare-free, directional lighting of objects such as plants and outdoor sculptures.
Tang, U.S. Pat. No. 4,325,110, discloses a vase-type illumination device comprising a transparent container, transparent base board, and a supporting stand and illuminating mechanism. The transparent base board can be either movably or immovably mounted on the underside of said container, while the flowers or various kinds of ornaments are inserted in place in the holding hole on the base board.
Dolan, U.S. Pat. No. 3,431,410, discloses an ornamental display having a multiplicity of fiber optic elements held together along a length adjacent one end and transversely unrestrained at the other end. A light source and a rotatable color wheel are positioned between the light source and the fiber bundle.
Wall, U.S. Pat. No. 3,624,385, discloses an adapter, which allows a spray of optical fibers to readily be connected or disposed in proximity to a light source.
Feldman, U.S. Pat. No. 5,951,140, discloses a display unit, typically intended for placement on a table that includes a plurality of flexible elongated electroluminescent sources connected to the individual display elements.
Cooper, U.S. Pat. No. 3,455,622, discloses a lighting device for transmitting light to inaccessible places using a bundle of optical fibers and a means of directing a concentrated column of visible light onto one end of the fibers. A means for substantially eliminating infrared energies from the concentrated column is disclosed.
Sussel, U.S. Pat. No. 4,170,036, discloses an article of jewelry which consists of first and second lengths of electrically conductive wire with a light emitting diode connected across a first set of the free ends of the wire lengths. An oscillator circuit and a low voltage power source are connected across the other free ends of the lengths of wire to provide a flashing circuit for the light emitting diode.
Blackerby, U.S. Pat. No. 4,866,580, discloses an ornamental lighting device which includes a housing defining a chamber therein and a power source disposed in the housing chamber. One or more LEDs are mounted in the housing wall. In one embodiment, the LEDs are provided with light enhancing members that serve to disburse, reflect or otherwise modify the light emitted from the LEDs.
Day et al., U.S. Pat. No. 6,296,364, discloses a light-emitting beaded necklace for ornamental decoration having a plurality of beads on an elongate thread. At lease one light source is enclosed within one of the beads.
Jensen et al., U.S. Application US2003/0035291, discloses an imitation candle having a body made from a translucent material having light transmissive properties similar to paraffin. The body is shaped to resemble a candle that is reduced by burning. An LED or similar high intensity light source is set in a cavity enclosed within this material. The LED emission levels are varied in a pseudo-random manner to simulate the flicker of candle light.
Ostema et al., U.S. Pat. No. 5,253,149, discloses illuminated jewelry connectable to a wearer as an earring, a clothes pendant or the like and includes a light emitting diode connected onto an enlarged flat base member at one end of an elongated stem.
Bae, U.S. Pat. No. 5,497,307, discloses illuminated jewelry that includes a housing containing a mercury switch, a mercury battery, a cap containing a light bulb, a clipping member for clipping to the wearer, whereby anytime the illuminating jewelry is moved, the jewelry illuminates in a blinking manner.
The use of small electric lamps to illuminate artificial flowers is known, but applicant is aware of no teaching that shows a means of illuminating real flowers from within. Indeed, no prior art found even suggests that it might be possible to propagate light through one or more layers of vegetable matter such as petals of a flower, so that a real plant might be illuminated from within for ornamental purposes.
SUMMARY OF THE INVENTION
Disclosed is a light source for internally illuminating live flowers and other products. The light source is formed in the shape of an elongated pin extending from a battery case having controls operatively connected to the light source. The elongated pin includes a sharp penetrating tip that surrounds the light source and is used for insertion within the structure of the plant, typically through the bottom of the flower or it can be concealed by placement through a stem and into the bottom of the flower. The device is of such a size that it can be supported by a plant without deformation of the plant.
Therefore, it is an objective of this invention to illuminate real flowers from within, permitting the beauty of these flowers to be enjoyed in many new venues of low ambient light and provide for an entirely new look for real flowers.
It is another objective of this invention to provide a sufficiently bright lighting means to reveal the internal structure of the flower as light passes through the flower petals, thereby yielding an even more fascinating sight.
It is a further objective of this invention to provide optimal visual effect by adjustably positioning the lighting source within the head of the flower. It is yet another objective of this invention to provide adjustable color and intensity of the light source for the optimal visual appearance of the illuminated flower.
The instant invention provides an economical, compact and effective means to illuminate real flowers from within the flower itself. Because the illumination source is from within the flower and not external to it, the visual effect is both surprising and pleasant.
An unexpected feature of the device of the instant invention is the ability of a single device to not only illuminate a single flower but also to cast significant light on adjacent flowers and thereby illuminates them as well.
While the device can be used with live, growing plants, it is anticipated that it will find most common use in cut flowers and arrangements of cut flowers. Additionally, the device could be used to illuminate food items from within, such as lemon or other fruit wedges or other products as well.
Other objectives and advantages of this invention will become apparent from the following description taken in conjunction with the accompanying drawings wherein are set forth, by way of illustration and example, certain embodiments of this invention. The drawings constitute a part of this specification and include exemplary embodiments of the present invention and illustrate various objects and features thereof.
BRIEF DESCRIPTION OF THE FIGURES
FIG. 1 shows one embodiment of the device of the instant invention;
FIG. 1 a is an exploded view of one embodiment of the device of the instant invention;
FIG. 1 b is a detail view showing relationship of light source to tube and piercing tip;
FIG. 1 c illustrates an embodiment employing integral light source and penetrating tip;
FIG. 2 shows the device of the instant invention in application;
FIG. 3 illustrates a second embodiment of the instant invention with extended leads;
FIG. 4 illustrates a second embodiment of the instant invention with a plurality of tips; and
FIG. 5 shows a third embodiment of the device of the instant invention employing an optical fiber.
DETAILED DESCRIPTION OF THE INVENTION
The device of the instant invention functions by placing a light source comprising a penetrating tip inside the core of the object to be illuminated. The lighting and positioning means must not detract from the overall beauty of the flower and must not cause damage to the flower such that the life of the bloom is significantly shortened. The device must also be of a size and weight that does not cause the flower or the flower stem to deform significantly. Further, the device can be of such a size that it could be used in flowers or flower arrangements in which the flower stem is very short, such as in a corsage or boutonniere.
One embodiment of the device of the instant invention 100 , FIGS. 1 , 1 a and 1 b , comprises case 11 which is attached to tube 12 . The distal end of tube 12 is attached to light source 13 which is contained in penetrating tip 14 . Contained within case 11 which is comprised of mating case members 10 is a power source such as a battery 17 . A first terminal of the power source is electrically connected via spring contact 18 to tube 12 , a second terminal of the power source is electrically connected to an electric wire 30 , which runs inside the hollow tube 12 . A resistor 19 may be employed in series fashion in this circuit to limit current to light source 13 . Light source 13 may be an LED, incandescent lamp or any other suitable source. Now referring to FIG. 1 b , first contact of light source 13 is electrically connected to the distal end of tube 12 , typically by soldering or other suitable method of bonding. A second contact of light source 13 is electrically connected to the free end of electric wire 30 thereby completing the circuit. Tube 12 may comprise a “stepped” end to facilitate bonding of light source 13 to tube 12 while permitting the electric wire to be routed and bonded to the second contact of light source 13 . Pull-tab 15 , which may be a strip of plastic, or other electrical insulator serves as a switch to power the device on. Pull-tab 15 may be placed between the batteries or other electrical contacts of the circuit as illustrated in FIG. 1 a . When pull-tab 15 is removed, the electrical circuit is completed and light source 13 is activated. Other known methods of switching the circuit on and off are anticipated and deemed to be within the scope of the instant invention.
FIG. 1 c illustrates an alternate embodiment in which the penetrating tip 14 comprises a miniature LED or other light source, which light source, is of an appropriate size and shape to function as a penetrating tip.
Now, referring to FIG. 2 , penetrating tip, 14 is inserted into the flower in or near the receptacle, 23 portion of the flower. This portion of the flower is situated between the peduncle and the calyx. If the receptacle is particularly tough or woody, penetrating tip 14 may be inserted directly into the petals 24 just above the upper portion of the receptacle. Case 11 is then manipulated so that penetrating tip 14 is positioned near the center of the flower or elsewhere as may be desired, e.g., within the corolla as illustrated in FIG. 2 .
The exact position of the tip is determined at the time of insertion by observing the illumination pattern of the petals. The illumination focus may be adjusted from a small bright spot when the tip is very near the surface of the top of the flower petals to a larger, less intense area of glow as the tip is positioned more deeply into the corolla. In one version of the device of the instant invention tube 12 is fabricated from a 1/16 inch outside diameter brass tube and penetrating tip 14 was produced from clear acrylic plastic. Any tube and tip materials may be employed in any manner of size and shape so long as they meet the needs of the instant invention. Penetrating tip 14 may be attached to the distal end of tube 12 by means of clear epoxy adhesive or any other suitable method. Penetrating tip 14 is preferably hollow to fit over light source 13 and end of tube 12 . Case 11 may be designed to resemble a leaf 25 or otherwise camouflaged so that it may be hidden in a flower arrangement.
Since the stem of a cut flower continues to provide hydration and some nutrients to the flower, it is desirable that the capillary process, which conveys these nutrients to the flower, not be significantly disturbed, otherwise the “life” of the flower will be compromised. Generally, the fibers and cellular structures, which form part of this nutrient supply system, are oriented longitudinally with respect to the growth direction of the plant. Evidence of this may be found by the manner in which a flower stem will split along its length. To minimize damage to the flower it is desired to sever as few of the capillaries as possible. This may be achieved by using a small penetrating tip 14 to split the flower at the desired point of insertion. Splitting of the flower is preferred as opposed to perforation. Penetrating tip 14 may comprise a sharpened tip for this purpose. An attachment means 16 in the form of a clip or tie may be employed to maintain relative position of flower illumination device 100 relative to flower 200 . Alternately, or in addition, florist's tape may be employed for this purpose.
The overall illumination effect is dependent on the exact nature of the flower to be illuminated as well as the light emitting properties of light source 13 . For example, a rose or carnation will provide a different look when lighted than an orchid. In flowers such as calla lilies the light source may be directly visible if viewed from above the flower. In this example, the flower glows from the outside and appears to have a “bright star” inside of it. The light emitted from the light source may comprise any color or combination of colors as may be desired. The apparent color of the item that is illuminated, for example, a white rose, is a function of not only the color of the item but also the light source. It is anticipated that the light source may be capable of generating a plurality of colors such as may be generated by a multicolored LED which colors may be controlled by an electronic circuit. Further, the light source may be steady or caused to flash or pulse in an interesting manner.
In a second embodiment of the invention as shown in FIG. 3 and FIG. 4 , flexible, electric wires 30 replace tube 12 or a portion of tube 12 . In this embodiment, case 11 may be located a considerable distance from penetrating tip 14 such as in a vase containing a bouquet of flowers. Case 11 may be incorporated into the vase or even made integral to the vase which includes an on-off switch 40 , as illustrated in FIG. 4 . In this arrangement, the length of the penetrating tip may be extended somewhat to form a handle portion and to assist the user in piercing of the flower and manipulation of light source 13 within the flower.
A third embodiment of the invention employs a light conducting member such as an optical fiber 51 to transmit light from a light source integral to case 11 to penetrating tip 14 . In this case penetrating tip 14 may be integral to optical fiber 51 .
The invention disclosed herein is anticipated to be used primarily with flowers however, the device may also be used to provide internal illumination of other products such as fruits or vegetables, for example, lemon, lime, or pineapple slices as may be served with tropical drinks. Similarly the device may be inserted into an olive or a cherry and served with a beverage. Additionally, the device can be inserted into soft cheeses, breads and the like as may be desired to create glowing appetizers.
It is to be understood that while we have illustrated and described certain forms of my invention, it is not to be limited to the specific forms or arrangement of parts herein described and shown. It will be apparent to those skilled in the art that various changes may be made without departing from the scope of the invention and the invention is not to be considered limited to what is shown in the drawings and described in the specification. | A small light source for internally illuminating live flowers and other products is formed in the shape of a pin with a battery case operatively connected to the light source. A sharp penetrating tip surrounds the light source and is fixed to a rigid tube for manipulating the device to insert the light source within the structure of the plant. The device is of such a size that it can be supported by a plant without deformation of the plant. | 5 |
This application has a priority based on a previously filed Provisional Application Ser. No. 60/246,220 filed Nov. 6, 2000.
BACKGROUND OF THE INVENTION
The device as described in the appended application is a device used to assist patients recovering from knee surgery. More particularly, the device is a medical therapy apparatus used to assists patients recover the range of movement in the knee joint after injury or surgery.
Following trauma, such as an injury or surgery, a patient will lose range of motion in the effected joint. Most frequently, the loss of range of movement is a result of trauma to the muscles, tendons, or ligaments. Frequently, the effected body parts must be forcibly stretched to regain the pre-trauma range of movement. The forceful stretching often requires that the joint be moved to or beyond a point of maximum comfortable extension and then either held in that position or moved further to stretch the effected muscles, tendons, or ligaments. The stretching must be controlled, as too great of stretching or too forceful of stretching will at least inhibit healing, if not re-injure the joint.
One of the difficulties of rehabilitation is for the patient to recover the loss of motion that the surgery or illness has taken. In the past, physical therapy has been used to restore the range of motion. However, physical therapy usually requires repetitive movement of the effected joint, often to the limits of motion and beyond, which all too frequently is both painful and time-consuming. So long as a physical therapist is assisting the patient with the prescribed exercises, recovery will proceed. However, when the exercises are not performed or performed improperly, the process of recovery slows or ceases.
An additional problem that may be encountered is that following an injury or surgery the knee joint may become unstable and the exercises are even more difficult to perform due to the instability. When another person assists the patient in performing the exercises, the other person may stabilize the joint so that the movement remains in the correct plane and the correct direction and no additional harm occurs to the joint. However, when the patient is exercising alone they do not have the luxury of the assistant and it becomes more difficult to perform the exercises. As a result, the patient may either not perform the exercises, or perform the exercises incorrectly. The results of either option are not conducive to recovery for the patient. With the reduction of length of hospital stays, and the increase in home health care a need for a simple device used to assist a patient with their therapy to regain the range of movement in the effected joint has become necessary.
Previously, other devices have been developed that attempt to resolve the problems. Some of the devices are complex and expensive and therefore are better suited for hospital use in a physical therapy department. This class of devices is beyond the cost that most patients can incur.
Presently, when the exercises are being done in a home environment, there are no appliances available to assist either the patient or the home health care professional with the therapy necessary to assist the patient in regaining the range of motion that the patient once had.
Without any suitable appliances to assist the patient, the patients must make do with their own ingeniousness, which often means that the patient must bend their body into an uncomfortable position and, from the uncomfortable position, urge their knee into a further bent position without twisting or otherwise moving the knee improperly. This task, all too often proves to be so difficult that the patient does not do the exercises and fails to regain the range of motion that the patients enjoyed before the injury or surgery.
SUMMARY OF THE INVENTION
The leg stretcher, as described herein, is a padded appliance for placement behind the knee and lower leg to support and guide the lower leg as the knee is moved through a range of movement. There is a planet olanar leg support mechanism for supporting the lower leg, having a cushioning mechanism formed on one end. The cushioning mechanism is provided to increase the comfort of the patient during use.
The leg stretcher may be attachable to the patient's leg to provide further comfort and utility. The leg stretcher may be attached using an attachment mechanism, such as flexible straps. The leg stretcher may include a strap that extends around the leg of the patient and the appliance itself allowing the patient to more easily reach the strap. Pulling on the strap will cause increased movement in knee joint without forcing the patient into an unduly uncomfortable position.
A feature of the leg stretcher is to provide an appliance for stabilizing a body limb while exercising to regain the pre-trauma range of motion.
It is another feature of the leg stretcher to provide an appliance that reduces the opportunity to perform prescribed exercises incorrectly.
It is still another feature of the leg stretcher to provide an appliance that enhances a patient's ability to perform prescribed exercises without assistance from another person.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a front elevation view of the leg stretcher.
FIG. 2 is a front perspective view of the leg stretcher with both a strap and a stabilizer attached.
FIG. 3 is a front perspective view of a second embodiment of the leg stretcher showing an alternate mechanism for attaching a strap.
DETAILED DESCRIPTION
The leg stretcher 10 , as shown in FIGS. 1 and 2, includes a leg support mechanism 12 for providing support to a leg, a cushioning mechanism 14 for providing comfort to the leg, and may include a stretching mechanism 16 for self-stretching of an injured knee and/or a stabilizing mechanism 17 for providing more stability to the leg stretcher 10 . These mechanisms 12 , 14 , 16 , 17 are described below more fully.
The leg support mechanism 12 may be of a variety of lengths and widths. The length needs to be long enough to provide stability when placed beneath a patient's lower leg and behind the patient's knee. The length may range from longer than the patient's lower leg to shorter than 17 inches. The preferable length ranges from approximately 16 inches to approximately 20 inches. The width may be slightly wider than the patient's lower leg. The width may range from several inches wider than the patient's lower leg to narrower than 4 inches. The preferable width ranges from approximately 4 inches to approximately 6 inches.
The leg support mechanism 12 may be of a variety of shapes. The preferable shape is approximately rectangular having a first end 18 , a second end 20 , a right side 22 , and a left side 24 . The leg support mechanism 12 may include two right angles located at the first end 18 . The leg support mechanism 12 may include rounded corners for more comfort to the back of the patient's knee. The top end 18 may have a curved portion for providing more comfort to the back of the patient's knee. The second end 20 generally will not be in contact with the patient's leg. The leg support mechanism 12 may be made of any material having sufficient strength and weight. The material needs to avoid degradation so that the leg support mechanism 12 does riot break or crack during use. The weight is not overly important, although the leg support mechanism 12 preferably is sufficiently lightweight to be portable while being sufficiently heavy enough to prevent breakage of the leg support mechanism 12 . Suitable materials include wood, hard polymers, or aluminum or other suitable material having the aforementioned properties.
The cushioning mechanism 14 , for providing comfort to the leg and knee, may be a variety of sizes. The cushioning mechanism 14 needs to be large enough to cover the first end 18 of the leg support mechanism 12 , although the cushioning mechanism 14 should be small enough to remain securely affixed to the first end 18 .
The cushioning mechanism 14 may be made of a variety of materials. The material may be any material that provides a cushion between the leg support mechanism 12 and the patient's knee. The material may be a cloth such as terry cloth, expanded polymer padding, sheepskin covering, vinyl padding, or any other suitable material having the properties of having a cushioning effect and providing sufficient longevity during use. A combination of these materials may be used to form the cushioning mechanism 14 .
The stretching mechanism 16 for self-stretching of an injured knee may include a strap 32 and a plurality of openings 34 defined by the leg support mechanism 12 . The strap 32 may range in length and material. The strap 32 needs to be long enough to be inserted into at least one opening 34 a of the plurality of openings 34 and reinserted into a second opening 34 b creating a loop 36 . The loop 36 may be long enough to allow the patient's ankle, shin, or lower leg to fit within the loop 36 . The length of the strap 32 may range from less than two feet to more than five feet. Preferably, the length of the strap 32 will be approximately three feet. The strap 32 may be made of any flexible material that does not crack or break easily. It is preferred that the strap 32 have sufficient diameter so that the strap 32 will not dig into the leg of the patient during use and create additional unnecessary pain for the patient. The strap 32 may be made of cotton, flexible plastic, or polyester, or other suitable material.
The plurality of openings 34 may be located, in pairs, at varying distances from the first end 18 , although preferably only one pair of openings 34 will be present. The pairs of openings allow the strap 32 to be placed at varying locations to enable multiple patients having varying leg lengths to use the same leg support mechanism 12 . The plurality of openings 34 may be different shapes and sizes. The plurality of openings 34 may be circular, square, rectangular or other shape. Preferably, the plurality of openings 34 are circular. The plurality of openings 34 may range in size from approximately one-half inch to approximately three inches. Preferably, the plurality of openings 34 is approximately one inch in size.
The stabilizing mechanism 17 may be attached to a bottom portion of the leg support mechanism 12 . The stabilizing mechanism 17 may be attached using a hinged mechanism, a temporary attaching mechanism or a permanent attaching mechanism. The stabilizing mechanism 17 may be attached towards the second end 20 or the stabilizing mechanism 17 may be attached towards toward the bottom center of the leg support mechanism 12 .
The stabilizing mechanism 17 may range in length and material. The length may range from a few inches to four or more feet and preferably is six inches to one foot. Different lengths may be used depending upon the patient, location of the patient and preferences of those involved in its use. The material needs to avoid degradation so that the stabilizing mechanism 17 does not break or crack during use. Suitable materials include, but are not limited to wood, hard plastic, or aluminum.
An alternative embodiment of the present invention 10 includes the leg support mechanism 12 , the cushioning mechanism 14 , and may include the stabilizing mechanism 17 as described above. The alternative embodiment of the present invention 10 includes the stretching mechanism 16 . The stretching mechanism 16 , for self-stretching of an injured knee, may include a strap 32 and a plurality of slots 38 defined by the leg support mechanism 12 . The strap 32 may range in length and material. The strap 32 needs to be long enough to be slid into at least one slot 38 a of the plurality of slots 38 on the left side 24 as well as slid into a second slot 38 b on the right side 22 creating a loop 36 . The loop 36 may be long enough to allow the patient's ankle, shin, or lower leg to fit within the loop 36 . The length of the strap 32 may range from less than two feet to more than five feet. Preferably, the length of the strap 32 will be approximately three feet. The strap 32 may be made of any material that does not crack or break easily. The strap 32 may be made of cotton, flexible plastic, or polyester, or other suitable material.
The plurality of slots 38 may be located, in pairs, at varying distances from the first end 18 . The pairs of slots allow the strap 32 to be placed at varying locations to enable multiple patients to use the same leg support mechanism 12 . The plurality of slots 38 may range in length from approximately one-half inch to approximately three inches. Preferably, the plurality of slots 38 is approximately one and one-half inches in length.
In its use, the leg stretcher 10 is easily prepared for use. The leg support mechanism 12 is disposed beneath the lower leg of the patient having a previously traumatized knee. The cushioning mechanism 14 is located adjacent to the injured knee. Once the leg support mechanism 10 is properly positioned, the injured knee may be stretched in one of three procedures.
In the first procedure, the patient may allow the lower portion of their leg to hang so that gravity may assist in stretching the injured knee. In the second procedure, a second person may stabilize the leg support mechanism 10 with one hand and use his/her other hand to apply pressure to the patient's shin or foot to stretch the injured knee. In the third procedure, the stretching mechanism 16 may be used. The strap 32 would be placed through the appropriate at least one openings 34 . The patient would then place the strap 32 over his/her lower leg/shin. Then the patient may pull on the strap 32 to stretch the injured knee.
Although the present invention has been described with reference to preferred embodiments, workers skilled in the art will recognize changes may be made in form and detail without departing from the spirit and scope of the invention. | A medical appliance for assisting in the performance of exercises for regaining lost range of motion in a previously traumatized knee joint of the leg of a patient having a planar leg support with a first end and a second end, the leg support further having a cushion attached on the first end thereof, the cushion surrounding the first end of the planar support and being further adapted for fitment adjacent to and behind the knee joint to support and locate the lower leg for performance of exercises, and an elongate stretcher removably attachable to the to the leg support whereby the patient may apply force to the to the stretcher increasing the range of movement in the previously traumatized knee. | 8 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to integrated circuits for economically and rapidly processing digital information produced in response to optical scanning of bar coded labels.
2. Description of the Prior Art
The size of an integrated circuit, i.e., the "chip size" is an important factor in the ultimate cost of the integrated circuit to the final user. Another important cost is the engineering and design cost. The larger the number of units of the integrated circuit which are manufactured, the smaller is the engineering and design cost per unit. However, the chip size becomes an increasingly dominant factor in the ultimate product cost as the manufacturing volume of the product increases. For state of the art MOS (metal-oxide-semiconductor) large scale integrated (LSI) devices, very large numbers of MOSFETS (metal-oxide-semiconductor field effect transistors) are fabricated on a single monolithic silicon "chip", which is frequently less than 250 mils square. Thousands of conductive lines, some composed of polycrystalline silicon and others composed of aluminum, interconnect the various elements of the MOSFETS. Minimum line widths and spacings between the respective lines and the MOSFETS must be maintained to avoid short circuits and parasitic effects. Yet the length of the interconnecting lines and their associated capacitances must be minimized not only to reduce chip size, but also to achieve maximum circuit operating speeds. A wide variety of trade-offs, including the necessity to minimize chip size, obtain a suitable chip aspect ratio (which enhances integrated circuit chip yield and wire bonding yield), increase circuit operating speed, reduce power comsumption, and achieve acceptable reliability are involved in obtaining an optimum "layout" (arrangement of MOSFETS and interconnection pattern therebetween) in order to obtain a MOSLSI circuit which is both economical and has acceptable operating characteristics. Often, the technical and commercial success of an electronic product utilizing MOSLSI technology may hinge on the ability of the chip designer to achieve an optimum chip topography.
A very high level of creative interaction between the circuit designer and the chip designer or layout draftsman is required to achieve a chip topography or layout which enables the integrated circuit to have acceptable operating speed and power dissipation and yet is sufficiently small to be economically feasible. Months of such interaction resulting in numerous trial layout designs and redesigns and circuit design revisions may be required to arrive at an optimum topography for a single MOSLSI chip. Although the computer aided design (CAD) approach in the past has been attempted in order to generate optimum MOSLSI topography designs, this approach has been only moderately successful, and only to the extent that the CAD approach sometimes provides a rapid chip topography design. However, such a topography design usually has mediocre performance and usually results in unduly large, uneconomical semiconductor chips. It is well established in the integrated circuit industry that CAD approaches to generating MOSLSI chip layouts do not yet come close to achieving the topography design optimization which can be accomplished by human ingenuity applied to the task.
Some of the numerous design constraints faced by the MOSLSI chip designer include specifications for the minimum widths and spacing of diffused regions in the silicon, the minimum size required for contact openings in the insulating field oxide, the spacings required between the edges of contact openings to the edge of diffused regions, minimum widths and spacing of polycrystalline silicon conductors, the fact that such polycrystalline silicon conductors cannot "cross over" diffused regions, the minimum widths and spacings between the aluminum conductors, and the constraint that conductors on the same layer of insulating oxide cannot cross over like conductors. The high amount of capacitance associated with diffused regions and the resistances of both diffused regions and polycrystalline silicon conductors must be carefully considered by the circuit designer and the chip designer in arriving at an optimum chip topography.
For many types of logic circuits, such as those in the present invention, a very large number of conductive lines between sections of the logic circuitry are required. The practically infinite number of possibilities for routing the various conductors and placing the various MOSFETS taxes the skill and ingenuity of even the most skillful chip designers and circuit designers, and is beyond the capability of the most sophisticated computer programs yet available.
Other constraints faced by the chip designer and circuit designer involve the need to minimize cross coupling and parasitic effects which occur between various conductive lines and conductive regions. Such effects may degrade voltages on various conductors, leading to inoperative circuitry or low reliability operation under certain operating conditions.
Accordingly, it is an object of the present invention to provide an integrated circuit chip for formatting digital characters by a pattern recognition array in response to optical scanning of a bar coded label, which integrated circuit has a topography which provides maximum possible circuit operating speed with lowest possible chip size and power dissipation.
SUMMARY OF THE INVENTION
Briefly described, and in accordance with one embodiment thereof, the invention provides topography for integrated circuits for sequentially receiving a plurality of digital character words produced in response to optical scanning of a bar coded label, the integrated circuit having first, second, third and fourth sequentially located edges forming a rectangle. The integrated circuit also sequentially receives a plurality of binary signals corresponding to a plurality of digital character words, the binary signals representing, respectively, validity, scanning direction, and timing of the digital character words. The integrated circuit outputs and transmits formatted character words to a digital processor system coupled to the integrated circuit. The integrated circuit includes input interface circuitry for receiving digital character words and the binary signals and also includes a plurality of shift registers coupled to the input logic circuitry for storing predetermined ones of the digital character words. In the described embodiment of the invention, the integrated circuit includes 12 shift registers arranged in four groups of three each. The character words are routed by means of a four frame state counters and associated control circuitry into the four groups of shift registers, respectively. The integrated circuit includes means for detecting when a valid, properly formatted character is loaded into one of the registers and means for interrupting a processor system when this condition occurs. The processor system transmits commands to the integrated circuit, thereby causing the integrated circuit to transmit the valid, properly formatted character word to an output bus. The input circuitry is located substantially closer to the third and fourth edges than to the first and second edges. The frame counters are located substantially closer to the fourth edge than to the second edge. The four groups of shift registers are located between the frame counters and the second edge. The processor command decoding system is located generally adjacent the second edge.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block diagram illustrating a pattern recognition and scanning system in which the integrated circuit of the present invention is included.
FIGS. 2A and 2B are a block diagram of the frame control array embodied in the integrated circuit of the present invention.
FIG. 3 is a block diagram illustrating the general location of sections of circuitry on the integrated circuit of the present invention.
FIG. 4 is a scale reproduction of a photomask utilized to define the pattern of the source-drain diffused regions and diffused interconnect regions in the integrated circuit of the present invention.
FIG. 5 is a scale reproduction of a photomask used to define the pattern of the ion implanted depletion regions of the integrated circuit of the present invention.
FIG. 6 is a scale reproduction of a photomask utilized to define the contacts made between the polycrystalline silicon conductors and the diffused regions of the integrated circuit of the present invention.
FIG. 7 is a scale reproduction of a photomask utilized to define the pattern of the polycrystalline silicon layer of the integrated circuit of the present invention.
FIG. 7A is identical to FIG. 7 except that major sections of circuitry of the integrated circuit of the present invention have been outlined and identified by reference numerals.
FIG. 8 is a scale reproduction of a photomask utilized to define the patterns of all conductor interconnection contacts in the integrated circuit of the present invention.
FIG. 9 is a scale reproduction of a photomask utilized to define the pattern of the metal interconnection layer of the integrated circuit of the present invention.
FIG. 10 is a scale reproduction of a photomask utilized to define the pattern for the passivation layer of the integrated circuit of the present invention.
FIG. 11 is a diagram illustrating the package and lead configuration of the package in which the integrated circuit of the present invention is ultimately housed.
DESCRIPTION OF THE INVENTION
The invention described herein is closely related to the disclosure in the patent application entitled "Symbol Decoding System", by Gene L. Amacher and Syed Naseem, Ser. No. 043,933 filed May 30, 1979 the patent application entitled "Symbol Processing System", by Denis M. Blanford and Syed Naseem, Ser. No. 043,971 filed May 30, 1979, the patent application entitled "Slot Scanning System", by Gene L. Amacher, Syed Naseem and Denis M. Blanford, Ser. No. 043,928, filed May 30, 1979 and the patent application entitled "Topography For Integrated Circuit Pattern Recognition Array", by Rod Orgill and and Michael Janes, Ser. No. 043,929, filed May 30, 1979, all assigned to the present assignee, all filed on even date herewith, and all incorporated herein by reference.
Referring now to FIGS. 2A and 2B, there is shown a block diagram of the character recognition system in which the present embodiment is utilized including a slot scanner 20 which causes a laser beam to be reflected to produce a scanned pattern above and in front of a slot or opening adjacent the laser. If a UPC tag is placed such that the laser beam crosses the tag, thereby reflecting the light from the bars and spaces which compose the UPC tag, a photodetector receiving the reflected light will transform the reflected light into an electrical signal. A video amplifier (not shown) located in the scanning unit generates, in response to the generated electrical signals, digital pulses STV (Set Video) indicating a space-to-bar transition and RTV (Reset Video) indicating a bar-to-space transition. The time interval between these pulses is a function of the width of the bar or space. The pulse width of the signals STV and RTV can be from 25 nanoseconds to 2 microseconds. Alternate valid signals are never closer together than 350 ns. This means that following a valid STV or RTV, multiple pulses may occur during this 350 ms. time period.
These time intervals are transmitted to a counter control 22 (FIG. 1) in which the intervals are converted to a binary number by an interval counter which is part of a FIFO (First-In, First-Out) IC array. The FIFO time averages the time between intervals to an acceptable period. Either of the signals STV and RTV will stop the interval counter and cause that interval count along with the state of a VIDEO flip-flop (not shown) to be stored in a FIFO shift register (not shown). The VIDEO flip-flop will be true for a bar. The interval counter at this point is reset and the next interval count is started. If the output of the interval counter is greater than 1280 counts (32 us.), a overflow condition is created. In the overflow state, every 800 ns. of the count of 1280 and the last state of the VIDEO flip-flop will be loaded into the FIFO shift register. The occurrence of the next STV or RTV signal will result in the loading of an additional 1280 count into the FIFO shift register. This condition will cause an error signal to be generated which, as will be described more fully hereinafter, will be sensed by the system at this time. Using this error signal, the system will disregard the data that is being generated by the slot scanner unit 20 and the counter control unit 22. The data contained in the FIFO shift registers located in the counter control 22 will be outputted to a decoder chip 24 which is the subject of the present application under the control of clock pulses generated by a 40 Mhz. oscillator 26. The FIFO shift registers will output 11 bits of binary data representing the width of the interval being scanned over bus 23 (FIG. 1) together with a VIDEO signal indicating whether the interval is a bar or a space. Also outputted from the counter control unit 22 to the decoder chip 24 are clock pulses CLK.
The decoder chip 24 (FIG. 1) contains a number of binary adders, comparators, shift registers and discrete logic elements which are used to decode the data being scanned by the slot scanner unit 20. The decoder chip 24 will output a hexadecimal number which includes four BCD bits representing a decimal character in addition to indicating margins, center bands and error. Three additional binary bits are outputted by the decoder chip 24 which represent the signal MARK to indicate the interval is a bar or a space, the signal EQUAL indicating that the current interval taken together with the three previous intervals are either equal or not equal in width to the previous four intervals, and the signal PARITY indicating that the interval is either odd or even parity, thereby locating the interval on the left or right side of the center band.
The output signals from the decoder chip 24 are transmitted to a frame control chip 28 (FIG. 1) which separates the valid data from the invalid data being outputted by the decoder chip 24. The frame control chip 28 filters out this valid data by checking for framing characters, that is, in and out margins, in and out center bands, and character equality to identify the valid characters being decoded by the decoder chip 24. A good segment of valid data is then transmitted over bus 29 to a microprocessor 30 for further processing. The frame control chip 28 functions also as a communication adapter for transmitting data to be sent from the microprocessor through an interface adapter 32 to a host terminal 34 over bus 33. The microprocessor 30 monitors photodetectors in the slot scanner unit 20 to determine when an item is in position to be read by the slot scanner. This data is transmitted to the microprocessor 30 over a bus 36 coupled to a scanner control unit 38. Upon receiving the required control signals, the microprocessor will then start monitoring the frame control chip 28 for information. The microprocessor does correlation analysis and modulo ten check to determine if it has a valid tag. Once a valid tag is assembled, the data is transmitted to the host terminal through the interface adapter 32. Reference should be made to the co-pending application Amacher et al Ser. No. 043,933 and Naseem et al. Ser. No. 043,928 filed on the same date as the present application for a full disclosure of the details of the operation of the frame, that is the control chip 28 and the microprocessor 30, respectively, each assigned to the present assignee of the application.
The basic circuit configuration of the present invention is illustrated in FIGS. 2A and 2B. The input logic interface 80 receives data from the pattern recognition array. The input interface logic 80 includes an input latch, a BCD function decoder, a frame decoder, and a shift register data latch.
Four binary coded hexadecimal data bits plus a parity bit are outputted from the input logic 80 to each of a group of twelve shift registers 82, which are used to "capture" valid data. The capture of the data by the shift registers 82 is controlled by four frame state counters 85. These four counters use the decoded binary coded hexadecimal functions and frames from the input interface logic 80 to detect which segments of data are valid and should be captured. Circuitry associated with the one of shift registers 82 in which the valid data is contained notifies the microprocessor 86 when a valid segment is captured.
The valid data is transmitted over the SR data bus 88 to the command decode logic 90, which also contains bus drivers. Command decode logic 90 sends the valid data to the microprocessor 86 over the microprocessor data bus 92 in response to an appropriate command received by microprocessor 86 (which is not included in the frame control chip 28).
The SR data bus 88 also connects the command decode logic 90 with a host communication interface 94. This interface is necessary to couple the microprocessor with a peripheral device, such as a terminal 96. The terminal is linked to the communication interface 94 via an optically coupled interface adapter (OCIA) 98. When the microprocessor 86 wishes to send data to the terminal 96, the data travels over the DB bus 92 to the host communication interface 94, which signals the terminal 96.
The terminal 96 sends data to the microprocessor in a similar manner. The terminal 96 clocks the data via the OCIA 98 to the host communication interface 94, which notifies the microprocessor 86 that there is data waiting. The microprocessor 86 then transmits a signal which loads the data onto the SR data bus 88. The interface 90 transfers the data from the SR bus 88 to the processor DB bus 92 and sends the data to the microprocessor 86.
The parity of the valid data segment is detected by the parity decode ROM 99. The ROM 99 receives the parity data from the SR bus 88 and sends the decoded information to the command decode logic 90, which sends the information to the processor 86 via the DB bus 92.
It should be noted that microprocessor 86, OCIA 98 and terminal 96 are not included in frame control integrated circuit 28, and are included only to facilitate the foregoing discussion of the operation of frame control chip 28.
Referring now to FIG. 3, frame control chip 28 includes consecutively located edges 111, 112, 113, and 114, which form a rectangle. Input buffer circuitry contained in block 80 of FIG. 2A is contained in section 40, which is positioned along edges 111 and 114. Section 41 includes the registers F3A, F3B, and F3C of FIG. 2A. Section 42 includes shift registers F1A, F1B and F1C of FIG. 2A. Section 43 includes shift registers F2A, F2B and F2C of FIG. 2A. Section 44 contains shift registers F0A, F0B and F0C of FIG. 2A.
The placement of shift registers F0A, F0B, and F0C are indicated by blocks 44C, 44B and 44A, respectively, in FIG. 7A. The placement of shift registers F3C, F3B, and F3A is indicated by reference numerals 41A, 41B, and 41C, respectively, in FIG. 7A. The placement of shift registers in section 42, from left to right, is F1A, F1B, F1C. The position of shift registers in section 43 from left to right is F2C, F2B, and F2A. It was necessary to have parallel outputs from shift registers F0A and F2A. This made it desirable to place shift registers F0A and F2A adjacent to each other, as shown in FIG. 7A. It was also necessary to provide more connections between shift register F0C and circuitry in periodic clock control section 50 than for others in the shift registers. This led to positioning shift register F0C as close as possible to section 50, as subsequently explained. Periodic clock control section 50 was placed near edge 113 partly because this chip area was made available by placement of read only memory 45 along edge 113.
Read only memory 45 was placed along edge 113 to minimize lengths of connections between read only memory 45 and the input/output buffers in section 55, which is located along edge 112 in the upper right hand corner of chip 28.
The foregoing considerations led to arranging of the shift registers in section 43 in a pattern which is the mirror image of the arrangement in section 44. Thus, shift registers F0A and F2A are adjacent. A special shift register cell which allowed providing parallel outputs to the control logic was provided. It should be noted that the original layout plan called for arrangement of the shift registers in the order F0A, F0B, F0C, F1A, F1B, F1C, F2A, F2B, F2C, F3A, F3B, and F3C. It was discovered that this approach would have required a substantially larger chip size.
A read only memory (ROM) (which decodes the order of the character word data received from one of the shift registers before outputting that data to microprocessor 86 of FIG. 2B to produce the PARITY bit which indicates that the bar coded label has been scanned from right to left, rather than from left to right) is located in section 45, adjacent to edge 113.
The above mentioned sections 41, 42, 43, 44 and 45 are located generally closer to edge 112 than to edge 114, but are separated from edge 112 by parallel-to-serial, serial-to-parallel conversion circuitry contained in section 53. The circuitry in section 53 operates to effect communication with host terminal 96 in FIG. 2B and contains circuitry in block 94 of FIG. 2B.
Microprocessor command decode circuitry is located in section 54, which includes the circuitry of block 90 of FIG. 2B, and is located in section 54 adjacent to edge 112. By placing section 54 so that the outputs of the microprocessor command decode logic could be routed through section 17' to the respective shift register contol logic sections 46-49, a minimum capacitance is obtained for the longest output line. The signals on microprocessor bus 92 (FIG. 2B) are received by bonding pads and input buffers in section 55, which is located adjacent to the microprocessor command decode section 54 in order to minimize chip area consumed by routing the outputs of the I/O buffers in section 55 to microprocessor command decode section 54. The placement of parallel-to-serial, serial-to-parallel conversion circuitry in section 55 adjacent to microprocessor command decode section 54 resulted in making efficient use of chip area made available by the above mentioned placement of sections 54 and 55 and effected convenient routing of signals on bus 88 (FIG. 2B) from the various shift registers to the circuitry in section 53 (which corresponds to circuitry in block 94 of FIG. 2B). The original layout plan was to distribute the circuitry in section 53 uniformly across the top of chip 28 as shown in FIG. 3, but for the foregoing reasons involving placement of sections 54 and 55, it became necessary to place section 55 as shown.
A plurality of shift register bits are contained in section 52, which is located along edge 114. A number of shift register buffers located in section 52 provide signals which are utilized in various locations in chip 28, especially in the lower left portion of the chip as shown in FIG. 3. The original layout plan called for placement of the various shift register buffers close to the various circuitry which received signals produced at the outputs of these shift register buffers. Due to the fact that the shift register buffers all receive a common clock signal, it was found that less chip area was required to group all of the shift register buffers in section 52 and route the outputs to the necessary locations than to utilize the initial layout plan for these shift register buffers. The amount of capacitance for the clock line, and consequently the amount of chip area required for the clock generator required to generate the common clock signal, was substantially reduced by grouping all of the subject shift register buffers in section 52.
Buffers for the PARITY, and EQUAL bits and BCD0-BCD3 are contained in section 52, which is located adjacent the lower right hand corner of frame control chip 28 along edges 113 and 114 thereof. The bonding pads and input buffers for the PARITY, EQUAL, BCD0, BCD1, BCD2, and BCD3 inputs are located in section 51 in the lower right hand corner of chip 28 in order to enable the respective bonding pads to be wire bonded to predetermined leads of the package in which chip 28 is housed and to enable the outputs of the corresponding input buffers to be routed to the state counters in sections 56, 57, 58, and 59.
FIG. 7A shows the circuit sections in FIG. 3 superimposed accurately upon the reduced scale reproduction of the photomask used to define the pattern of the polycrystalline silicon layer of frame control chip 28.
Numerous design trade-offs and trial layouts were required to determine the illustrated relative locations of the frame state counters and the associated shift register frame control logic circuitry. The frame control logic circuitry (such as that contained in section 46), includes, for each of the shree shift registers included in each group, priority logic, a frame latch which inhibits clocking of BCD characters into that shift register when a properly formatted BCD character has been loaded therein, a load latch which enables data to be clocked out of the shift register onto the microprocessor data bus, reset logic circuitry which enables the power on reset circuitry or a microprocessor command to reset that register, an enable counter to control enabling shifting of a character into the next shift register of the group, and a shift register clock circuit.
The read only memory in section 45 was placed along the right hand edge 113 of frame control chip 28 rather than in the section 17' between sections 42 and 43. Section 17' contains some vertical polycrystalline silicon conductors and does not utilize the chip area in section 17' for placement of logic circuitry because additional area required for conducting operating power to the read only memory in section 45 and the periodic clock control circuitry in section 50 would result in a larger chip size if these sections were placed between sections 42 and 43. A plurality of metal shorting bars, such as 201, are provided on the metal layer shown in FIG. 9 to reduce voltage drops in the V SS conductors and the V CC conductors. The V SS shorting strip 203 and a V CC shorting strip 202 were provided around read only memory 45 to reduce voltage drops along the respective power supply voltage conductors.
Placement of the clock generator and toggle control circuitry in section 60 between the adjacent frame control circuitry sections permits use of balanced lengths of output lines driving the state counters and shift register control logic. This minimizes RC time delays which would result if particular output lines from the clock generator and toggle circuitry in section 47 were each required to extend across all of sections 46, 47, 48 and 49, rather than only two of of these sections.
A reset driver circuit was included in section 60 for providing reset signals to the respective frame shift register control logic sections 46, 47, 48, and 49 at the appropriate times. The circuitry in section 60 includes circuitry which receives information indicating when a valid character has been clocked into a particular one of the twelve shift registers. As mentioned above, associated with each of the twelve shift registers, respectively is a frame latch and a load latch (not shown in FIG. 2). The respective frame latches and load latches are controlled by adjacent frame shift register control logic. When a particular shift register has received a valid character, its frame latch is set, preventing any further information from being clocked into that shift register. After a valid character has been "captured" by setting of the frame latch for the capturing shift register, the load latch for that shift register is set. The load latch enables the captured character to be transmitted onto bus 88 in FIG. 2. The circuitry in section 60 includes a twelve input NOR gate which receives the outputs from the twelve load latches referred to above. The twelve frame latches and load latches are contained in their respective frame shift register control logic sections 46, 47, 48 and 49. The initial plan for the layout for this section was to provide a distributed NOR gate which included a plurality of input MOSFETS located close to the outputs of the respective load latches. In order to reduce the capacitance of the output of the twelve input NOR gate, it was found to be desirable to instead locate the entire twelve input NOR gate in section 60 and conduct the load latch outputs to the inputs of the twelve input NOR gate. These load signals then are decoded in section 60 to determine whether the present frame count is an even frame count (causing the F0 register group or the F2 register group to be clocked by its corresponding shift register control logic) or an odd frame (causing the F1 or F3 shift register group to be clocked by its corresponding shift register control logic). Location of section 60 midway across the chip, as shown in FIGS. 3 and 7A, facilitated the above described approach to decoding the load latch outputs and enabled convenient routing of signals between microprocessor command decode logic 54 and the respective frame shift register control logic sections. The outputs of circuitry in section 60 are utilized to control the four state counters. Acceptably low output capacitances are achieved by virtue of the central location of section 60.
Numerous trial layouts and much consultation between the chip designer and the circuit designer were required to arrive at a topography which effectively balances the previously mentioned trade-offs to obtain the high performance and minimum area configuration for frame control chip 28 shown in the drawings.
It should be noted that the scale reproductions of the photomask shown in FIGS. 4-10 can be used by one skilled in the art to produce a mask set which can be used to manufacture chip 28 in accordance with well known N-channel MOS manufacturing processes.
While the invention has been described with respect to a particular embodiment thereof, variations in the illustrated topography can be made by those skilled in the art without departing from the true spirit and scope of the invention. | An integrated circuit for sequentially receiving a plurality of digital character words produced in response to optical scanning of a bar coded label and a plurality of corresponding binary signals representing, respectively, validity, scanning direction, and timing of the digital character words includes first, second, third, and fourth sequentially located edges forming a rectangle. The integrated circuit includes input circuitry for receiving the digital character words and corresponding binary signals and further includes twelve shift registers for storing predetermined ones of the digital character words. Four frame counters and associated control circuitry responsive to the binary signals and the character words steer the incoming character words to predetermined ones of the shift registers. The integrated circuit outputs formatted character words to a digital processor system. A command decoder receiving commands from a digital processor system controls the outputting of valid, properly formatted digital character words from predetermined ones of the shift registers in response to an interrupt signal produced when a properly formatted character word is contained in one of the shift registers. The input circuitry is generally located adjacent the corner formed by the third and fourth edges. The frame counters and associated control circuitry are generally located substantially closer to the fourth edge than to the second edge. The twelve groups of shift registers are generally located between the frame state counters with their associated control circuitry and the second edge. The command decode circuitry is located adjacent the second edge. | 7 |
RELATED APPLICATIONS
This application is a continuation-in-part of U.S. patent application No. 08/019,419, filed on Feb. 19, 1993, now U.S. Pat. No. 5,341,970, entitled Acoustic Ceiling Patch Spray.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to surface texture materials, and more particularly to a novel pressurized substance in liquid or semi-liquid form which is storable and dispensable from an air-tight pressurized container to be sprayed onto a drywall or supporting surface so that after subsequent curing and hardening, a matching textured surface is provided with that of surrounding acoustic ceiling areas.
2. Brief Description of the Prior Art
It has been the conventional practice in the procedure of repairing drywall or patching acoustic ceiling areas to remove the damaged portion of the ceiling and subsequently fill any holes, depressions or the like with a prepared patch material. The patch or replacement material is applied by means of a trowel or other flat tool which will press the patch material into the hole or depression and which will prepare and provide a surface area to receive a finish surface coating. After the patch material has cured and adhered to the original support material, a smooth surface is provided which receives the final coating. This coating leaves a smooth surface which is not matched to the surrounding roughened or textured surface.
An acoustic ceiling surface usually presents a surface texture which is bumpy or presents an irregular look and sometimes is referred to as a "Popcorn effect". Such an appearance and surface texture cannot be attained through the use of smoothing tools or patch tools once the patch material has been applied to the damaged or repaired area. Therefore, difficulties and problems have been encountered which stem largely from the fact that the use and application of conventional patching material on acoustic ceiling repairs leaves a surface texture which does not match the surrounding area and which is noticeable after the repair has been completed.
With respect to conventional patch substances, prior means of dispensing such patch substances have included the use of air compressors or hand operated spray pumps of the type used to dispense insect repellant. These are inadequate because they are time consuming in use and require substantial cleanup. Also, two hands are normally required for directional control of the discharge or spray.
Therefore, a long-standing need has existed to provide a material that may be readily applied to a repaired patch or surface so that the repaired surface will match with the surrounding surface texture of an acoustic ceiling. Furthermore, there is a need for a surface texture material which may be applied to a repaired or patched area and which may be contained in a hand-held applicator, requiring only one hand, so that the material may be conveniently stored as well as applied to the repaired area in a simple and convenient manner.
SUMMARY OF THE INVENTION
Accordingly, the above problems and difficulties are obviated by the present invention which provides a novel material which is storable and dispensable from a convenient dispenser including a pressurized container holding a quantity of the acoustic ceiling surface texture material in a liquid or semi-liquid condition so that upon depression of a dispensing nozzle, the material will be discharged and directed to a patch area intended receive the surface texture material. The surface texture material includes a base, a filler, a binder, and at least one of an aggregate, a blowing agent and an expandable material, and an aerosol propellant serving as a carrier medium and a pressure source so that the texture material may be applied by spray and will adhere to the repaired patch and drywall surface.
In one form of the invention, the acoustic ceiling textured material may include: a base or emulsion of water and/or solvent, an adhesive binder made of a natural or synthetic polymer, a pressurized carrier for dispensing of the material such as a solvent/propellant aerosol, a filler made of limestone, mica and clay, and at least one of an aggregate and an expandable material. The expandable material, such as a polymer which is soft and expandable before curing, allows the textured material to expand after being dispensed from the container thereby providing the "popcorn effect".
Therefore, it is an object of the present invention to provide an acoustic ceiling spray patch material which is storable and dispensable from a hand-held dispensing unit for spray-on and direct application of the material in a liquid or semi-liquid form onto a repaired or patched area so that the surrounding surface texture will be visually and mechanically matched.
Another object of the present invention is to provide a material which is storable in and dispensable from an air-tight container such that the dispensing device may include as part of a nozzle a curved dispensing straw for directing the ingredient discharge in an overhead manner while the user is in a confined area with the device being held in a vertical position.
Another object of the present invention to provide an inexpensive, practical and economical means for matching the surface texture of a repaired or patched surface area on an acoustic ceiling with the surrounding acoustic surface texture.
A further object of the present invention is to improve the appearance of acoustic ceiling patched or repaired areas on a ceiling surface by employing a spray-on textured material which covers the patched or repaired areas and visually assumes the surface texture of the surrounding acoustic ceiling surface.
BRIEF DESCRIPTION OF THE DRAWINGS
The features of the present invention which are believed to be novel are set forth with particularity in the appended claims. The present invention may best be understood with reference to the following description, taken in connection with the accompanying drawings in which:
FIG. 1 is a pictorial view illustrating the direct application of the spray-on surface texture material from the dispenser of the present invention for repairing of an acoustic ceiling;
FIG. 2 is a transverse cross-sectional view of the repaired or patched area shown in FIG. 1 illustrating the dissimilarity in surface texture between the original ceiling surface and the surface of the patched areas;
FIG. 3 is a transverse cross-sectional view of the repaired or patched area on an acoustic ceiling and illustrating matching of surface texture between the surface of the patch and the surrounding ceiling surface after use of the novel spray-on surface textured material of the present invention; and
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring in detail to FIGS. 2 and 3, a fragmentary view is shown of a typical ceiling support panel or board and is identified by numeral 10. The panel 10 supports textured acoustic material 11 which has been damaged and a repair to the damaged area which takes the form of a patch 12. After curing, the patch becomes solidified and adheres to the edge marginal region of material 11 and surface of the panel 10 defining the area covered by the patch material. The surface texture of the original material 13 can be seen to be broadly defined as being bumpy, pebbled or presenting a popcorn look.
In FIG. 2, it can be seen that the patch 12 displays a smooth surface 14 usually attained by repeatedly drawing the edge of a hand tool, such as a trowel, across the surface. After drying or curing, the material of the patch 12 becomes hard and the surface 14 remains smooth and unmatched with the surrounding irregular or raised surface 13 carried on the panel 10. Although the surface 14 will accept a variety of coatings such as paint or the like in a conventional situation, the surface texture of the coating will not simulate or blend with the surrounding irregular surface 13 of original material 11. Visually, the flat patch area 14 will always be noticeable and indicate the presence of a repair.
Referring now in detail to FIGS. 1 and 3, the surface textured material 15 discharged from a dispenser 16 is illustrated as being applied to the smooth surface 14 of the patch 12. In this connection, a bumpy and irregular surface is placed on the flat surface 14 so as to be compatible with, blend with and be coextensive with the surrounding ceiling surface area 13. By employment of the present invention, the surface texture of both the patch 12 and the surrounding acoustic ceiling material 13 are substantially identical and matched so that no visual indication is presented or noticeable pertaining to a repair or patch. The material being applied is broadly indicated by numeral 15 which is contained within the dispenser container 16 and applied in the form of a spray in either liquid or semi-liquid condition. Application is achieved by depression of a pump or spray nozzle 17 which permits discharge of the pressurized material carried within the container 16. Such an application of the material occurs directly on the desired area 14 by the user who hand-carries the container 16 and operates the nozzle 17 on site with one hand. Waste and loss of material is avoided since the discharge is under the control of the user through the application of the discharge nozzle 17. Therefore, there is no residue or excess material that is not used which requires disposal. Furthermore, the material 15 is lumpy and, after curing on surface 14, provides an irregular surface compatible and matching the surrounding material surface area. Furthermore, the material in the container is considered a finished product and does not require additives of any kind and the labeling on the container may provide identification numbers and laboratory information.
To control discharge of the material 15 and avoid waste, distribution may be via an elongated, curved or arcuate open-ended hollow straw or tube 19. The user may hold the dispenser container 16 in a vertical or upright orientation with the end of the straw or tube in close proximity to the repair area. The other end of the straw or tube is pressed into an mating fit with the conventional discharge opening of the nozzle 17. Without the use of a curved straw or with a straight straw, the user must hold the container at an awkward angular position since the discharge from the dispenser nozzle is always normal to the longitudinal vertical axis of the dispenser.
Preferably, an example of the material 15 comprises a base material, a filler, an adhesive binder, a propellant and at least one of a blowing agent, an aggregate and an expandable material. The base material may be any aqueous substance such as water and/or a non-aqueous substance such as alcohol, aromatic or aliphatic hydrocarbon, ketone, ester or the like. The filler may be any material that can serve as an extender or bodifier such as limestone, clay or silica, or similar materials, or a mixture thereof. Adhesive binder is an adhesive that may take the form of a natural polymer, such as gums and resins and the like, or a synthetic polymer, such as polyvinyl alcohol, alkyd resins, etc, or a combination thereof. The adhesive binder will serve to keep the material 15 in place once it has cured. The propellant will act to push or propel the material 15 from the container. The propellant may be hydrocarbon, dimethyl ether, carbon dioxide, nitrogen, compressed gas or any combination of the above said propellants or any other propellant used in the aerosol industry such as hydrofluorocarbons. Blowing agent is a material which can be in a solution or in suspension in other materials and which when exposed to atmospheric pressure or high temperatures expands and creates empty spaces within the surrounding materials. The blowing agent may be a low boiling point hydrocarbon and/or solvent. Aggregate can be any material which may be chopped or ground into small pieces and incorporated with the other materials to provide irregular texture to the material 15. The aggregate may be polystyrene foam, cork, sponge, perlite, or oatmeal.
Expandable material serves to provide tensile strength to the material 15. Any material which may add tensile strength such as a polymer, polyurethene and/or any polymeric materials which will be soft and expandable before curing, may be used. The use of the expandable material, for example a polymer, promotes expansion of the material 15 after it has been dispensed from the container 16, while allowing the material 15 to remain in an unexpanded state before dispensing. The expandable material creates the "popcorn effect" and allows the material to match the surrounding acoustic ceiling material. The components of the material which provide the material 15 with the requisite form or body, such as the filler and/or aggregate, must be put into a finer state for storage in an aerosol container and subsequent release through a conventional nozzle. The expandable material or polymer promotes expansion of the finer components to provide the "popcorn effect" as if the components had been prepared and applied in a conventional manner. Therefore, the expandable material makes storage of the material 15 in an airtight aerosol container and dispensing therefrom a desirable alternative to conventional storage and dispensing alternatives.
The material 15 may comprise any one of or any combination of a blowing agent, an aggregate or an expandable material.
By way of an example the hardenable flowable material 15 the present invention may have the following composition by percentage weight:
______________________________________Water/Solvent 25-50%Filler 50-80%Binder 1-4%Aggregate 5-20%Expandable Material 2-10%Blowing Agent 1-5%Liquefied Propellant 5-25%Compressed Gas 0-1%______________________________________
Also by way of a more specific example the hardenable flowable material 15 of the present invention may have the following basic composition by percentage weight:
______________________________________Limestone 48%Mica 7%Clay 1%Polyvinyl Alcohol 1%Perlite 2%acrylic emulsion 2-10%Low Boiling Point Hydrocarbon 1%Dimethyl Ether 9%Water Quantity Sufficient to achieve 100%______________________________________
wherein the limestone, mica and clay are in powder form, the low boiling point hydrocarbon may be a blend in any proportion of isobutane and propane and the acrylic emulsion which is used in the above example constitutes the expandable material and is for example that which is sold under the tradename Neocryl A-639.
Further, the composition of the material 15, as described directly above, may contain a defoaming agent such as silicone (0.10%), a preservative (0.10%), an antifreeze (0.20%), a leveling or "smoothing" agent such as amino methyl propanol (0.07%) and a thickener such as min-ugel (0.2%) and/or methocel (0.15%).
In an alternative embodiment, one component, the polyvinyl alcohol, present in 1% by weight, may serve as both the binder and the expandable material.
Further, in order to adjust the finished appearance of the material 15, acrylic polymer and/or copolymer may be added in an appropriate amount, which will increase the hardness and body. Further, alcohol and/or solvent may be added to effect faster drying times.
As illustrated in FIG. 1, the material 15 is applied directly to the smooth surface 14 and when dried or cured results in an irregular surface having a texture compatible and matched with the surrounding surface texture of the acoustic ceiling. The patch material 12 is dried and cured in preparation for receiving the material 15 and the adhesive binder included in the material 15 insures adhesion of the material to the patch area. Even if small amounts of the material would extend beyond the surface 14 onto the surrounding material, the surface would still be matched and no unsightly patch edges or dissimilar surface texture would be detectable.
The patch material may be applied via a straw 19. The hollow straw 19 may have a curved central longitudinal axis with this axis, at the input end being normal to the central longitudinal axis of the container when the input end is fitted into the mated opening in nozzle 17. If the curved central longitudinal axis associated with the discharge opening at the other end of the straw is essentially parallel to the container longitudinal axis, the user may hold the container in an upright position while distributing the hardenable substance onto an overhead patch area.
While particular embodiments of the present invention have been shown and described, it will be obvious to those skilled in the art that changes and modifications may be made without departing from this invention in its broader aspects and, therefore, the aim in the appended claims is to cover all such changes and modifications as fall within the true spirit and scope of this invention. | An acoustic ceiling patch or textured material in the form of a sprayable composition including a base, a filler and a binder as well as a propellant or carrier storable and dispensable from a pressurized dispenser having a delivery nozzle and a removable dispensing tube. An aerosol system with a spray nozzle is included on the container for selective discharge of the textured material onto a prepared patch area which may be on a drywall or support panel so as to match and blend with the surrounding acoustic ceiling surface area in order to provide a continuous and unbroken coextensive surface texture of mechanically and visually matched material. A distribution straw is included for selectively conducting the textured material in a desired direction while holding the dispenser upright. | 1 |
BACKGROUND OF THE INVENTION
The present invention relates to a sound damping device for damping the sounds produced by sound sources, and more particularly to a muffler for reducing the noise of the combustion and exhaust of an internal combustion engine or the like.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a muffler which can not only damp the combustion and exhaust sounds of the internal combustion engine, but also damp the noise produced in the muffler.
It is another object of the present invention to provide a muffler of which exhaust resistance is small.
According to the present invention, there is provided a muffler which comprises an inner shell having first and second expansion chambers which are coaxially arranged and connected to each other through a communicating passage; an outer shell spacedly covering the inner shell to define therebetween first, second, third and fourth isolated chambers, the first and second isolated chambers surrounding the first expansion chamber, while, the third and fourth isolated chambers surrounding the second expansion chamber; first means connecting the first expansion chamber with the first isolated chamber to allow the latter to show a sound damping effect; second means connecting the first expansion chamber with the second isolated chamber to allow the latter to show a sound damping effect; third means connecting the upstream and downstream portions of the second expansion chamber with the third isolated chamber to allow the latter to show a sound damping effect; fourth means connecting the upstream and downstream portions of the second expansion chamber with the fourth isolated chamber to allow the latter to show a sound damping effect; an inlet means leading to the first expansion chamber to introduce thereinto an exhaust issued from a noise source; and outlet means extending from the second expansion chamber to the open air to discharge the exhaust in the second expansion chamber into the atmosphere.
BRIEF DESCRIPTION OF THE DRAWINGS
Other objects and advantages of the present invention will become clear from the following description when taken in conjunction with the accompanying drawings, in which:
FIG. 1 is a schematic illustration of a conventional muffler;
FIG. 2 is a longitudinally sectioned view of a muffler according to the present invention;
FIG. 3 is a laterally sectioned view of the muffler of the invention, which is taken along the line III--III of FIG. 2; and
FIG. 4 is a laterally sectioned view of a modification of the muffler of FIG. 2, which is taken along a line corresponding to the line III--III of FIG. 2.
DESCRIPTION OF THE PRIOR ART
Prior to describing the muffler of the invention, a conventional muffler for an internal combustion engine will be described with reference to FIG. 1 in order to clarify the invention.
The conventional muffler 10 shown in FIG. 1 comprises generally a shell 12 of which interior is divided into four chambers 14, 16, 18 and 20 by three partition walls 22, 24 and 26. An exhaust gas inlet tube 28 from the exhaust manifold of an internal combustion engine (not shown) leads to the chamber 18, so that the chamber 18 acts as a first expansion chamber. The first expansion chamber 18 and the chamber or resonance chamber 20 are connected through a first communicating pipe 30 supported by the partition wall 26, so that the interior of the pipe 30 and the chamber 20 constitute a so-called Helmholz's resonator 32 which primarily affects low frequency sounds. A second communicating pipe 34 connects the first expansion chamber 18 to the chamber 14 to allow the latter to act as a second expansion chamber. The pipe 34 is formed with a plurality of perforations 36 through which the interior of the pipe 34 and the chamber or resonance chamber 16 are communicated. An exhaust gas outlet pipe 38 extends from the second expansion chamber 14 to the atmosphere, extending across the chambers 16, 18 and 20, as shown. The pipe 38 is formed with a plurality of perforations 40 through which the interior of the pipe 38 is communicated with the resonance chamber 16. The chamber 16 and the perforations 36 thus constitute, as a whole, a resonator 42 which primarily affects high frequency sounds.
However, in practical use, the muffler of the above type has a tendency of producing a considerable noise due to its inherent construction. Experiment has revealed that the noise is caused by vibration of the shell 12 and that the vibration is mainly caused by the pulsating exhaust gas successively rushed into the first expansion chamber 18. In fact, the noise generated by the vibrating shell 12 is freely transmitted to the open air because of absence of any means which suppresses the vibration of the shell 12. One measure to solve this drawback is to increase the mechanical strength of the shell 12 by increasing the thickness thereof. However, this measure induces inevitably a heavier and higher cost construction of the muffler and thus, the measure is not practical.
Furthermore, the muffler of the above-mentioned type exhibits a high exhaust resistance because of looped ways of the exhaust gas in the muffler. As is known, the high exhaust resistance will reduce power and fuel economy of the engine.
DESCRIPTION OF THE INVENTION
Therefore, to solve the above-mentioned drawbacks is an essential object of the present invention.
Referring to FIGS. 2 and 3, especially FIG. 2, there is shown a first embodiment of the present invention. The muffler 44 of this embodiment comprises an elongate inner shell 46 including two elongate dish-shaped plates 48 and 50, each having two swelled portions 48a and 48b (or 50a or 50b). The two plates 48 and 50 are coupled with each other to define in the inner shell 46 thus formed a first communicating passage 52, a first enlarged chamber 54, a second communicating passage 56, a second enlarged chamber 58 and a third communicating passage 60 which are coaxially arranged in this order, as shown. The first enlarged chamber 54 is connected through the first communicating passage 52 to the exhaust manifold of an internal combustion engine (not shown), so that the first enlarged chamber 54 functions as a first expansion chamber. The swelled portions 48a and 50a of the plates 48 and 50 are formed with respective flanged openings 62 and 64 which face each other. The passages thus defined by the respective flanged openings 62 and 64 extend perpendicular to the longitudinal axis of the inner shell 46. The second enlarged chamber 58 connected through the second communicating passage 56 to the first expansion chamber 54 functions as a second expansion chamber. The second expansion chamber 58 is communicated with the atmosphere through the third communicating passage 60.
The inner shell 46 is spacedly and tightly disposed in an elongate outer shell 66 which includes two elongate dish-shaped plates 68 and 70, each having two swelled portions 68a and 68b (or 70a and 70b). As will be understood from FIG. 3, each of the inner and outer shell plates 48, 50, 68 and 70 has a flange (no numeral) throughout the peripheral portion thereof. The coupling between the associated plates is made by mating and welding the associated flanges of them by employing a seam-welding technique. The inwardly recessed portions 68c and 70c of the outer shell plates 68 and 70 contact with the associated portions of the inner shell plates 48 and 50, so that first, second, third and fourth cavities 72, 74, 76 and 78 are defined between the associated swelled portions 68a and 48a, 70a and 50a, 68b and 48b, and 70b and 50b, respectively. The first and second cavities 72 and 74 are communicated with the first expansion chamber 54 through the respective flanged openings 62 and 64, so that the first cavity 72 and the passage of the flanged opening 62 constitute a first resonator 80, while, the second cavity 74 and the passage of the flange opening 64 constitute a second resonator 82. The volume V of each cavity 72 or 74, the sectional area S of each flanged opening 62 or 64 and the axial length l of the same are so determined as to damp sounds having a predetermined low frequency level f (f=(C/2π)√(S/Vl), where; c=sound velocity). The inner shell plate 48 is formed at the second and third communicating passages 56 and 60 with a plurality of perforations 84 and 86 through which the third cavity 76 is communicated with the interior of the inner shell 46. Similar to this, the other inner shell plate 50 is formed at the second and third communicating passages 56 and 60 with a plurality of perforations 88 and 90 through which the fourth cavity 78 is communicated with the interior of the inner shell 46. With this construction, the third and fourth cavities 76 and 78 function as first and second resonance chambers, respectively. The perforations 84 and 86 and the first resonance chaber 76 thus constitute a third resonator 92, and the perforations 88 and 90 and the fourth resonance chamber 78 constitute a fourth resonator 94. The sectional area of each perforation 84 or 86 is different from that of the perforation 88 or 90, so that the third and fourth resonators 92 and 94 affect sounds having different high frequencies.
In the following, operation of the muffler 44 of the invention will be described.
The exhaust gas from the engine (not shown) is, first, introduced or rushed into the first expansion chamber 54 where the gas is suddenly expanded to reduce the vibration energy thereof. The predetermined low frequency sounds are removed or at least reduced by the first and second resonators 80 and 82. The exhaust gas is then introduced through the second communicating passage 56 into the second expansion chamber 58 where the gas is expanded again to reduce the vibration energy thereof to its minimum level. The gas is then discharged into the atmosphere through the third communicating passage 60. During flowing through the second and third communicating passages 56 and 60, the exhaust gas loses the predetermined high frequency sounds by the third and fourth resonators 92 and 94. With this manner, the combustion and exhaust sounds or noises are damped sufficiently.
In the muffler 44 of the present invention, the following desirable effect is achieved which is not expected from the conventional muffler as described hereinabove.
Similar to the conventional muffler, the pulsating and rushing exhaust gas from the engine forces the inner shell plates 48 and 50 to vibrate at a certain level producing a considerable noise at that portion. However, in the invention, such noise is not directly transmitted to the outside of the muffler 44 because of the presence of the chambers 72, 74, 76 and 78 which surround the inner shell 46. In fact, these chambers function as a noise damper.
Referring to FIG. 4, there is shown a modification 44' of the muffler according to the present invention, in which similar parts to those of the above-mentioned muffler 44 are designated by the same numerals. The view of this drawing is taken along a line located at a portion corresponding the portion where the line III--III of FIG. 2 is located. As is seen from the drawing, the muffler 44' of this modification features that the swelled portions 48a and 50a of the inner shell 46 are formed somewhat depressed as compared with those of FIG. 3. With the depressed configuration of them, the stiffness of the muffler 44' against the vibration in the direction of the arrow A is improved. Thus, in this modified muffler 44', the noise damping effect is much more improved.
As is described hereinabove, in the present invention, the inner shell into which the exhaust gas from the engine is rushed is enclosed by a so-called noise damping means which comprises the sound damping chambers 72, 74, 76 and 78. Thus, the noise produced by the vibrating inner shell 46 is not directly transmitted to the outside of the muffler. Furthermore, the aligned arrangement among the first communicating passage 52, the first expansion chamber 54, the second communicating passage 56, the second expansion chamber 58 and the third communicating passage 60 reduces the exhaust resistance of the muffler. | An inner shell having aligned first and second expansion chambers is spacedly disposed in an outer shell in a manner to define therebetween four isolated chambers upstreamly positioned two of which surround the first expansion chamber and downstreamly positioned two of which surround the second expansion chamber. The first expansion chamber is connected through respective flanged openings to the upstreamly positioned isolated chambers to allow these chambers to show a sound damping effect. The upstream and downstream portions of the second expansion chamber are connected through respective groups of perforations to the downstreamly positioned isolated chambers to allow these chambers to show a sound damping effect. | 5 |
CROSS-REFERENCE TO RELATED APPLICATION
This application is a continuation-in-part (CIP) of copending U.S. patent application Ser. No. 09/298,902 filed on Apr. 26, 1999, now abandoned, the entire content of which is expressly incorporated hereinto by reference.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to material suitable for the interior or exterior trim of an automobile (hereinafter simply called an “interior or exterior trim material”) which comprises a thermoplastic elastomer having improved weather resistance due to incorporation of a specific UV absorber; i.e., alkyl benzoate having a specified chemical structure. More particularly, the present invention relates to an interior or exterior trim material having improved weather resistance and resistance to weather-induced coloring.
2. Background Art
Conventionally, vinyl chloride resins have been widely used as interior or exterior trim materials. However, use of vinyl chloride resins has recently been restricted because of concerns in relation to environmental pollution, calling for substitution by non-halogen resins.
One possible substitute may be realized by use of a thermoplastic elastomer having resin properties suitable for an interior or exterior trim material. An interior or exterior trim material is required to have high weather resistance and resistance to weather-induced coloring, because the material is exposed to strong sunshine at high temperature while, for example, the automobile is parked outdoors.
Conventionally, a variety of UV absorbers and photostabilizers have been disclosed, and use method of these compounds has been suggested for imparting weather resistance to polyolefin resins used as polymer materials for general molding. Examples of UV absorbers include benzotriazole UV absorbers, benzophenone UV absorbers, phenoltriazine UV absorbers, and alkyl or aryl benzoate UV absorbers; and examples of photostabilizers include hindered amine photostabilizers.
For example, Japanese Patent Application Laid-Open (kokai) No. 54-21450 discloses a method for improving weather resistance of polyolefin resins by combined use of 3,5-di-tert-butyl-4-hydroxybenzoic acid hexadecyl ester (which is an alkyl benzoate UV absorber), and a benzotriazole UV absorber or a benzophenone UV absorber. Japanese Patent Application Laid-Open (kokai) No. 55-54339 discloses a method for improving weather resistance of polypropylene resins by combined use of the above-mentioned 3,5-di-tert-butyl-4-hydroxybenzoic acid hexadecyl ester and pentaerythritol dialkyldiphosphite. Japanese Patent Application Laid-Open (kokai) No. 56-62835 discloses a method for improving weather resistance of polyolefin by combined use of the above-mentioned 3,5-di-tert-butyl-4-hydroxybenzoic acid hexadecyl ester and a hindered amine photostabilizer.
Regarding the above-mentioned 3,5-di-tert-butyl-4-hydroxybenzoic acid hexadecyl ester, which is an alkyl benzoate UV absorber, Japanese Patent Application Laid-Open (kokai) No. 58-84839 discloses use thereof for pipes made of poly-1-butene; Japanese Patent Application Laid-Open (kokai) No. 1-62360 discloses use of the same for polypropylene resins which are subjected to radiation sterilization and used in the field of medicine, and Japanese Patent Application Laid-Open (kokai) No. 7-188473 discloses use of the same as materials in the agricultural field.
Japanese Patent Application Laid-Open (kokai) No. 7-179719 discloses use of 3,5-di-tert-butyl-4-hydroxybenzoic acid 2,4-di-tert-butylphenyl ester (which is an aryl benzoate UV absorber) as an automobile material.
Thus, a variety of methods have been disclosed for improving weather resistance of polymer materials for general molding. However, no known UV absorbers or photostabilizers provide satisfactory effects. Thermoplastic elastomers which are to be used as substitutes for interior or exterior trim materials are no exception; they also involve the same problems. However, no method for improving properties of thermoplastic elastomers has been known. An object of the present invention is to solve the above problems inherent to thermoplastic elastomers.
SUMMARY OF THE INVENTION
In view of the foregoing, the present inventors have conducted careful studies and have found that, when a 3,5-dialkyl-4-hydroxybenzoic acid alkyl ester is added to a thermoplastic elastomer, there can be obtained an interior or exterior trim material which has excellent weather resistance, and resistance to weather-induced coloring, without causing bleeding or fogging, or contamination, such as plate-out, of processing apparatuses. The 3,5-dialkyl-4-hydroxybenzoic acid alkyl ester is an UV absorber of alkyl benzoate among other benzoate compounds.
Accordingly, in a first aspect of the present invention, there is provided an interior or exterior trim material which comprises a thermoplastic elastomer composition containing 100 parts by weight of a thermoplastic elastomer and 0.001-10 parts by weight of an alkyl benzoate compound represented by the following formula (I):
wherein each of R 1 and R 2 is a hydrogen atom, a C1-C8 alkyl or cycloalkyl group, or a C6-C12 aryl, alkylaryl, or arylalkyl group; and R 3 is a C1-C30 alkyl group.
Preferably, each of R 1 and R 2 in the alkyl benzoate compound represented by formula (I) is a C1-C8 alkyl group.
Preferably, each of R 1 and R 2 in the alkyl benzoate compound represented by formula (I) is a tertiary butyl group or a tertiary amyl group.
Preferably, R 3 in the alkyl benzoate compound represented by formula (I) is a C6-C8 alkyl group.
Preferably, the thermoplastic elastomer is a polyolefin thermoplastic elastomer.
Preferably, the interior or exterior trim material further contains a hindered amine photostabilizer.
Preferably, the hindered amine photostabilizer has a 1,2,2,6,6-pentamethyl-4-piperidyl group.
Preferably, the interior or exterior trim material further contains a phosphorus-containing antioxidant of the following formula in an amount of 0.001-10 parts by weight.
Preferably, the interior or exterior trim material further contains a pigment.
Preferably, the interior or exterior trim material is used as a facing material for a ceiling, seat, or dashboard.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Thermoplastic Elastomers
Examples of thermoplastic elastomers used in the present invention include polyolefin thermoplastic elastomers and block copolymer-type polystyrene thermoplastic elastomers. The polyolefin thermoplastic elastomer comprises polyolefin resins such as polypropylene and polyethylene serving as hard segments and rubber compositions such as EPDM serving as soft segments. The block copolymer-type polystyrene thermoplastic elastomer comprises polystyrene serving as hard segments and polydienes such as polybutadiene or polyisoprene serving as soft segments. Alternatively, a blend of the polyolefin elastomers and the polystyrene elastomers may also be used as the thermoplastic elastomer of the present invention.
The methods for combining soft segments and hard segments in thermoplastic elastomers may be roughly divided into simple blending, implantation by copolymerization, and dynamic cross-linking.
Combinations of segments of polystyrene thermoplastic elastomers include a styrene-butadiene-styrene block copolymer (SBS), a styrene-isoprene-styrene block copolymer (SIS), a styrene-ethylene-butylene-styrene block copolymer (SEBS), a styrene-ethylene-propylene-styrene block copolymer (SEPS), a hydrogenated polymer of any one of the four copolymers, a hydrogenated polymer of random SBR (HSBR), and a blend of polypropylene and one or more arbitrary members selected from among these polymers.
Alkyl Benzoate Compounds Represented by Formula (I)
Examples of alkyl groups represented by R 1 and R 2 in the above formula (I) include alkyl groups such as methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl, tert-butyl, pentyl, tert-pentyl, hexyl, heptyl, octyl, and tert-octyl; cycloalkyl groups such as cyclopentyl and cyclohexyl; aryl groups such as phenyl and naphthyl; alkylaryl groups such as methylphenyl and butylphenyl; and arylalkyl groups such as phenylmethyl, 1-phenylethyl, and cumyl.
Examples of alkyl groups represented by R 3 include methyl, ethyl, propyl, isopropyl, butyl, isobutyl, secondary-butyl, tertiary-butyl, pentyl, tertiary-pentyl, hexyl, heptyl, octyl, tertiary-octyl, 2-ethylhexyl, nonyl, decyl, undecyl, dodecyl, tridecyl, tetradecyl, pentadecyl, hexadecyl, heptadecyl, octadecyl, behenyl, and triacontyl.
More specifically, examples of the alkyl benzoate compounds represented by formula (I) include the following compounds (Nos. 1-5). However, the present invention is in no way limited by the following illustrations.
The thermoplastic elastomer composition of the present invention comprises the aforementioned thermoplastic elastomer (100 parts by weight) and the aforementioned alkyl benzoate compound (0.001-10 parts by weight). When the amount of the alkyl benzoate compound is less than 0.001 parts by weight, sufficient weather resistance required for an interior or exterior trim material cannot be obtained. In contrast, an amount thereof in excess of 10 parts by weight is not preferable, because the compound may bleed from the interior or exterior trim material because of a change in the environment, such as a rise in temperature.
The thermoplastic elastomer composition of the present invention is appropriately used as interior or exterior trim materials; for example, for materials of ceilings, doors, seats, trunks, wipers and bumper, which are formed by use of known methods such as extrusion molding, injection molding, compression molding, or lamination. The thermoplastic elastomers are preferably used as interior trim materials for ceilings, seats, and dashboards.
Hindered amine photo-stabilizers may optionally be added into the thermoplastic elastomer composition of the present invention. The addition of the hindered amine photo-stabilizers advantageously amplifies the effect of aforementioned alkyl benzoate compounds used in the present invention; specifically, enhancement in weather resistance.
In addition, additives such as widely-used antioxidants may be used in combination with the above composition, and examples of the antioxidants include a phosphite compound, a phenol compound, and a sulfur compound.
Ultraviolet absorbers other than the alkyl benzoate compounds of the present invention may be used in combination with the above-described composition.
Examples of the above-described hindered amine photo-stabilizers include 2,2,6,6-tetramethyl-4-piperidyl benzoate, N-(2,2,6,6-tetramethyl-4-piperidyl)dodecylsuccinic imide, 1-[(3,5-di-tert-butyl-4-hydroxyphenyl)propionyloxyethyl]-2,2,6,6-tetramethyl-4-piperidyl(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, bis(2,2,6,6-tetramethyl-4-piperidyl)sebacate, bis(1,2,2,6,6-pentamethyl-4-piperidyl)sebacate, bis(1,2,2,6,6-pentamethyl-4-piperidyl)-2-butyl-2-(3,5-di-tert-butyl-4-hydroxybenzyl)malonate, N,N′-bis(2,2,6,6-tetramethyl-4-piperidyl)hexamethylenediamine, tetra(2,2,6,6-tetramethyl-4-piperidyl)butanetetracarboxylate, bis(2,2,6,6-tetramethyl-4-piperidyl) di(tridecyl)butanetetracarboxylate, bis(1,2,2,6,6-pentamethyl-4-piperidyl) di(tridecyl)butanetetracarboxylate, 3,9-bis[1,1-dimethyl-2-{tris(2,2,6,6-tetramethyl-4-piperidyloxycarbonyloxy)butylcarbonyloxy}-ethyl]-2,4,8,10-tetraoxaspiro[5.5]undecane, 3,9-bis[1,1-dimethyl-2-{tris(1,2,2,6,6-pentamethyl-4-piperidyloxycarbonyloxy)butylcarbonyloxy}ethyl]-2,4,8,10-tetraoxaspiro[5.5]undecane, 1,5,8,12-tetrakis[4,6-bis{N-(2,2,6,6-tetramethyl-4-piperidyl)butylamino}-1,3,5-triazin-2-yl]-1,5,8,12-tetrazadodecane, a 1-(2-hydroxyethyl)-2,2,6,6-tetramethyl-4-piperidinol/dimethyl succinate condensation product, a 2-tert-octylamino-4,6-dichlcro-s-triazine/N,N′-bis(2,2,6,6-tetramethyl-4-piperidyl)hexamethylenediamine condensation product, an N,N′-bis(2,2,6,6-tetramethyl-4-piperidyl)hexamethylenediamine/dibromoethane condensation product, 2,2,6,6-tetramethyl-4-hydroxypiperidin-N-oxy, bis(2,2,6,6-tetramethyl-N-oxylpiperidine)sebacate, tetrakis(2,2,6,6-tetramethyl-N-oxylpiperidyl)butane-1,2,3,4-tetracarboxylate, tetrakis(1,2,2,6,6-pentamethyl-4-piperidyl) 1,2,3,4-butanetetracarboxylate, and 3,9-bis(1,1-dimethyl-2-(tris (2,2,6,6-tetramethyl-N-oxylpiperidyl-4-oxycarbonyl)butylcarbonyloxy)ethyl)-2,4,8,10-tetraoxaspiro[5.5]undecane, especially carboxylic acid esters of 1,2,2,6,6-pentamethyl-4-piperidinol or 2,2,6,6-tetramethyl-4-piperidinol.
The hindered amine photostabilizer is most preferably present in an amount between about 0.10 to about 0.50 part by weight, for example, between about 0.15 to about 0.30 part by weight, based on 100 parts by weight of the thermoplastic elastomer.
Examples of the phosphite antioxidants includes tris(nonylphenyl)phosphite, tris(2,4-di-tert-butylphenyl)phosphite, tris[2-tert-butyl-4-(3-tert-butyl-4-hydroxy-5-methylphenylthio)-5-methylphenyl]phosphite, tridecyl phosphite, octyldiphenyl phosphite, di(decyl)monophenyl phosphite, di(tridecyl)pentaerythritol diphosphite, distearylpentaerythritol diphosphite, di(nonylphenyl)pentaerythritol diphosphite, bis(2,4-di-tert-butylphenyl)pentaerythritol diphosphite, bis(2,6-di-tert-butyl-4-methylphenyl)pentaerythritol diphosphite, bis(2,4,6-tri-tert-butylphenyl)pentaerythritol diphosphite, bis(2,4-dicumylphenyl)pentaerythritol diphosphite, tetra(tridecyl)isopropylidenediphenol diphosphite, tetra(tridecyl)-4,4′-n-butylidenebis(2-tert-butyl-5-methylphenol)diphosphite, hexa(tridecyl)-1,1,3-tris(2-methyl-4-hydroxy-5-tert-butylphenyl)butane triphosphite, 2,2′-methylenebis(4,6-di-tert-butylphenyl)-2-ethylhexyl phosphite, 2,2′-methylenebis(4,6-di-tert-butylphenyl)octadecyl phosphite, 2,2′-ethylidenebis(4,6-di-tert-butylphenyl)fluorophosphite, tetrakis(2,4-di-tert-butylphenyl)biphenylene diphosphonite, 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide, tris(2-[(2,4,8,10-tetrakis(tert-butyl)dibenzo[d,f][1,3,2]dioxaphosphebine-6-yl)oxy]ethyl)amine, and a phosphorous acid ester of 2-ethyl-2-butylpropylene glycol and 2,4,6-tri-tert-butyl phenol. Of these, bis(2,6-di-tert-butyl-4-methylphenyl)pentaerythritol diphosphite represented by the following formula is preferable in that it provides particularly excellent stabilizing effect.
Examples of the phenol antioxidants include 2,6-di-tert-butyl-p-cresol, 2,6-diphenyl-4-octadecyloxyphenol, stearyl(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, distearyl(3,5-di-tert-butyl-4-hydroxybenzyl)phosphonate, thiodiethylene glycol bis[(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], 1,6-hexamethylenebis[(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], 1,6-hexamethylenebis[(3,5-di-tert-butyl-4-hydroxyphenyl)propionic acid amide], 4,4′-thiobis(6-tert-butyl-m-cresol), 2,2′-methylenebis(4-methyl-6-tert-butylphenol), 2,2′-methylenebis(4-ethyl-6-tert-butylphenol), a bis[3,3-bis(4-hydroxy-3-tert-butylphenyl)butyric acid]glycol ester, 4,4′-butylidenebis(6-tert-butyl-m-cresol), 2,2′-ethylidenebis(4,6-di-tert-butylphenol), 2,2′-ethylidenebis(4-sec-butyl-6-tert-butylphenol), 1,1,3-tris(2-methyl-4-hydroxy-5-tert-butylphenyl)butane, bis[2-tert-butyl-4-methyl-6-(2-hydroxy-3-tert-butyl-5-methylbenzyl)phenyl]terephthalate, 1,3,5-tris(2,6-dimethyl-3-hydroxy-4-tert-butylbenzyl)isocyanurate, 1,3,5-tris(3,5-di-tert-butyl-4-hydroxybenzyl)isocyanurate, 1,3,5-tris(3,5-di-tert-butyl-4-hydroxybenzyl)-2,4,6-trimethylbenzene, 1,3,5-tris[(3,5-di-tert-butyl-4-hydroxyphenyl)propionyloxyethyl] isocyanurate, tetrakis[methylene-3-(3′,5′-di-tert-butyl-4′-hydroxyphenyl)propionate]methane, 2-tert-butyl-4-methyl-6-(2-acryloyloxy-3-tert-butyl-5-methylbenzyl)phenol, 3,9-bis[1,1-dimethyl-2-{(3-tert-butyl-4-hydroxy-5-methylphenyl)propionyloxy}ethyl]-2,4,8,10-tetraoxaspiro[5.5]undecane, and triethylene glycol bis[(3-tert-butyl-4-hydroxy-5-methylphenyl)propionate].
Examples of the sulfur-containing antioxidants include dialkyl thiodipropionates such as dilauryl thiodipropionate, dimyristyl thiodipropionate, and distearyl thiodipropionate; and β-alkylmercaptopropionic acid esters of polyol such as pentaerythritol tetra(β-dodecylmercaptopropionate).
Examples of the ultraviolet absorbers other than the alkylbenzoate compounds of the present invention include 2-hydroxybenzophenones such as 2,4-dihydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-octoxybenzophenone, and 5,5′-methylenebis(2-hydroxy-4-methoxybenzophenone); 2-(2′-hydroxyphenyl)benzotriazols such as 2-(2′-hydroxy-5′methylphenyl)benzotriazol, 2-(2′-hydroxy-3′,5′-di-tert-butylphenyl)benzotriazol, 2-(2′-hydroxy-3′,5′-di-tert-butylphenyl)-5-chlorobenzotriazol, 2-(2′-hydroxy-3′-tert-butyl-5′-methylphenyl)-5-chlorobenzotriazol, 2-(2′-hydroxy-5′-tert-octylphenyl)benzotriazol, 2-(2′-hydroxy-3′,5′-dicumylphenyl)benzotriazol, and 2,2′-methylenebis(4-tert-octyl-5-benzotriazolyl)phenol; benzoates such as phenyl salicylate, resorcinol monobenzoate, and 2,4-di-tert-butylphenyl 3′,5′-di-tert-butyl-4′-hydroxybenzoate; substituted oxanilides such as 2-ethyl-2′-ethoxyoxanilide and 2-ethoxy-4′-dodecyloxanilide; and cyanoacrylates such as ethyl α-cyano-β,β-diphenylacrylate and methyl 2-cyano-3-methyl-3-(p-methoxyphenyl)acrylate.
The thermoplastic elastomer composition of the present invent on may also comprise heavy metal deactivators, nucleating agents, metallic soap, hydrotalcites, pigments, organic tin compounds, plasticizers, epoxy compounds, foaming agents, antistatic agents, flame retardants, lubricants, processing aids, and inorganic fillers, such as talc, silica, mica, calcium silicate, calcium carbonate, barium sulfate, zinc oxide, magnesium hydroxide or a mixture thereof. The inorganic filler is incorporated in an amount of not more than 30 parts by weight, based on 100 parts by weight of the thermoplastic elastomer.
Particularly, in the thermoplastic elastomer composition of the present invention, the color of the product is easily adjusted, and various known pigments can be used for the product, since plate-out of pigments from the composition into a processing machine does not occur.
Examples of pigments used in the thermoplastic elastomer composition of the present invention include inorganic pigments, azo pigments, nitro pigments, acine pigments, acidic dye lake pigments, vat dye pigments, isoindolinone pigments, basic dye lake pigments, mordant dye pigments, quinacridone pigments, phthalocyanine pigments, nitroso pigments, daylight fluorescent pigments, metal powder pigments, and polymer coupled pigments.
When the thermoplastic elastomers of the present invention are produced, the methods for addition of alkylbenzoate compounds and other additives thereto are not limited, and additives may be used in the following forms: powder, water dispersions such as emulsions or suspensions, and organic solutions.
Although the types of blenders are not limited, when powder additives are used, a ribbon mixer or a Henschel mixer is useful for dry blending, and a uniaxial or biaxial extruder is useful for kneading. A conventional vertical mixer is sufficient for blending when additives assume the forms of water dispersions or solutions.
Additionally, various processes for addition may be employed in accordance with the forms of additives. For example, powder additives can be added during molding of the thermoplastic elastomer compositions, and adsorption or impregnation of additives into a molded product may be performed by dipping a molded product into an additive solution after molding. As another method for addition during molding, the additives may be kneaded in a final blending process after preparation of a blended master batch of high concentration, or through granulation of powder additives to depress a dust.
The present invention will next be described in more detail by way of examples, which should not be construed as limiting the invention thereto.
EXAMPLE 1
Propylene resin (60 parts by weight), EPR (20 parts by weight), talc (20 parts by weight), titanium oxide (2 parts by weight), calcium stearate (0.05 parts by weight), stearyl (3,5-di-tert-butyl-4-hydroxyphenyl)propionate (0.1 parts by weight), tris(2,4-di-tert-butylphenyl)phosphite (0.05 parts by weight), tetrakis(1,2,2,6,6-pentamethyl-4-piperidyl) 1,2,3,4-butanetetracarboxylate (0.15 parts by weight) and an alkyl benzoate compound (Compound No. 1) (0.1 parts by weight) were blended in a ribbon mixer. The resultant mixture was supplied to a pelletizer and extruded at 250° C., to thereby prepare pellets.
Subsequently, after the above pellets were melted at 250° C., 2-mm thick sheets were prepared by injection molding, so as to serve as an interior or exterior trim material. The sheets were tested for weather resistance (time until occurrence of cracking) and weather coloring (yellowness index after 480 hours) by use of a sunshine weatherometer under the following conditions: black panel temperature: 83° C., 18-minute rain in a 120-minute cycle.
Ten test pieces (25 mm×50 mm×2 mm) of an interior or exterior trim material were placed in an 80° C. oven, and after elapse of one week their surfaces were visually observed for occurrence of bloom, as well as for severity of any bloom found. The results are evaluated as follows. O: no bloom, X: bloom on the entire surface.
A test tube containing 25 grams of a specimen was covered with a glass plate, and heated in a 100° C. oil bath for 48 hours, to thereby check for presence of deposited matter and the degree thereof (fogging) in the same manner as the bloom test. The results are evaluated as follows. O: no deposition over the glass plate, X: deposition over the entire glass surface. The results are shown in Table 1.
COMPARATIVE EXAMPLE 1
The same procedure as in Example 1 was performed, except that no alkyl benzoate compound was used (Comparative Example 1-1), an aryl benzoate compound serving as a UV absorber was used in place of the above compound (Comparative Example 1-2), or a UV absorbing compound other than a benzoate compound was used in place of the above compound (Comparative Example 1-3). The results are shown in Table 1.
TABLE 1
Time at
which
cracking
Yellow-
occurred
ness
UV absorber
(hr)
Index
Bloom
Fogging
Example 1
Compound
2900
2.3
◯
◯
No. 1
Comp Ex. 1-1
None
1000
5.1
◯
◯
Comp Ex. 1-2
Comp.
2100
12.2
X
X
Compound 1 *1
Comp Ex. 1-3
Comp.
1100
4.5
X
X
Compound 2 *2
*1 3,5-di-tert-butyl-4-hydroxybenzoic acid-2,4-di-tert-butylphenyl ester
*2 2-(2′-hydroxy-5′-methylphenyl)-5-chlorobenzotriazole
EXAMPLE 2
The procedure of Example 1 was performed, except that propylene resin (65 parts by weight), EPDM (15 parts by weight), talc (20 parts by weight), titanium oxide (2 parts by weight), Phthalocyanine Blue (1 part by weight), hydrotalcite (0.1 parts by weight), tetrakis[methylene-3-(3′,5′-di-tert-butyl-4′-hydroxyphenyl)propionate]methane (0.1 parts by weight), bis(2,6-di-tert-butyl-4-methylphenyl)pentaerythritol diphosphite (0.1 parts by weight), 3,9-bis[1,1-dimethyl-2-{tris(1,2,2,6,6-pentamethyl-4-piperidyloxycarbonyloxy)butylcarbonyloxy}ethyl]-2,4,8,10-tetraoxaspiro[5.5]undecane (0.2 parts by weight), and alkylbenzoate (Compound No. 1) (0.3 parts by weight) were blended, to thereby prepare pellets. By use of a kneading roller at 240° C., the pellets were molded into a sheet having a thickness of 0.1 mm.
A test piece of 25 mm×50 mm×0.1 mm was prepared from the obtained sheet, and the time at which cracking of the piece initiated was measured under the same conditions as in Example 1, by use of a sunshine weatherometer, to thereby evaluate the weather resistance thereof. Bloom and fogging of the piece were also evaluated in the same manner as in Example 1. The results of evaluation are shown in Table 2.
COMPARATIVE EXAMPLE 2
The procedure of Example 2 was performed, except that no alkylbenzoate was used (Comparative Example 2-1), arylbenzoate was used as an ultraviolet absorber (Comparative Example 2-2), or a compound other than a benzoate compound was used as an ultraviolet absorber (Comparative Example 2-3). The results are shown in Table 2.
TABLE 2
Time at
which
cracking
occurred
UV absorbers
(hr)
Bloom
Fogging
Example 2
Compound No. 1
2700
◯
◯
Comp. Ex.
2-1
None
800
◯
◯
2-2
Comp. Compound 1 *1
1000
X
X
2-3
Comp. Compound 2 *2
1800
X
X
*1 and *2 correspond to the compounds of the same number shown in Table 1.
EXAMPLE 3
The procedure of Example 2 was performed, except that propylene-ethylene copolymer (70 parts by weight), SBS (30 parts by weight), Phthalocyanine Blue (1 part by weight), calcium stearate (0.2 parts by weight), tetrakis[methylene-3-(3′,5′-di-tert-butyl-4′-hydroxyphenyl)propionate]methane (0.2 parts by weight), bis(2,6-di-tert-butyl-4-methylphenyl)pentaerythritol diphosphite (0.2 parts by weight), bis(2,2,6,6-tetramethyl-4-piperidyl)sebacate (0.3 parts by weight), and alkylbenzoate compound (Compound No. 1) (0.3 parts by weight) were blended, to thereby prepare pellets. By use of a kneading roller at 240° C., the pellets were molded into a sheet having a thickness of 0.1 mm.
A test piece was prepared from the sheet in the same manner as in Example 2, and weather resistance and resistance to weather-induced coloring thereof were evaluated by use of a sunshine weatherometer in the same manner as in Example 1 except that rainfall cycling was omitted. Weather resistance was evaluated in terms of degradation time, and resistance to weather-induced coloring was evaluated in terms of yellowness index after 2000 hours.
Transfer of pigments from the piece to the kneading roller resulting from the additives was considered to constitute plate-out. Specifically, after preparation of the aforementioned compounds, a sheet was prepared, by use of a kneading roller, from a vinyl chloride resin containing a white pigment. Blue-coloring of the sheet of vinyl chloride resin was evaluated by visual inspection as follows, X: obvious coloring, Δ: slight coloring, O: no coloring. The results are shown in Table 3.
COMPARATIVE EXAMPLE 3
The procedure of Example 3 was performed, except that arylbenzoate was used as an ultraviolet absorber in place of the alkylbenzoate compound (Comparative Example 3-1), or a compound other than a benzoate compound was used as an ultraviolet absorber (Comparative Example 3-2). The results are shown in Table 3.
TABLE 3
Time until
Yellowing
embrittlement
(resistance
(hr)
to weather-
(weather
Plate-
induced
Test Compound
resistance)
out
coloring)
Example 3
Compound No. 1
3300
◯
4.6
Comp.
Comp. Compound 1 *1
2300
Δ
15.6
Ex. 3-1
Comp.
Comp. Compound 2 *2
1500
X
10.8
Ex. 3-2
1* and 2* correspond to the compounds of the same number shown in Table 1.
EXAMPLE 4
Propylene resin (60 parts by weight), EPR (20 parts by weight), talc (20 parts by weight), titanium oxide (2 parts by weight), calcium stearate (0.05 parts by weight), tetrakis[methylene-3-(3′,5′-di-tert-butyl-4′-hydroxyphenyl)propionate]methane (0.1 parts by weight), tetrakis(1,2,2,6,6-pentamethyl-4-piperidyl) 1,2,3,4-butanetetracarboxylate (0.15 parts by weight), alkylbenzoate compound (Compound No. 1) (0.2 parts by weight), and additives shown in Table 4 (0.1 parts by weight) were blended, and the resultant mixture was extruded at 250° C. to prepare pellets. Subsequently, a sheet having a thickness of 2 mm was prepared from the pellets through injection molding at 250° C., and the yellowness index thereof was measured. Weather resistance and resistance to weather-induced coloring were evaluated by use of a sunshine weatherometer in the same manner as in Example 1, except that rainfall cycling was omitted. Weather resistance was evaluated in terms of time until initiation of cracking, and resistance to weather-induced coloring was evaluated in terms of yellowness index. The results are shown in Table 4.
TABLE 4
Time until
initiation of
Yellowness
Additives
cracking (hr)
Index
Example 4-1
none
1400
10.2
4-2
2112 *3
1400
6.2
4-3
HP-10 *4
1600
5.1
4-4
PEP-36 *5
2200
3.0
*3 tris(2,4-di-tert-butylphenyl) phosphite
*4 2,2′-methylenebis(4,6-di-tert-butylphenyl)-2-ethylhexyl phosphite
*5 bis(2,6-di-tert-butyl-4-methylphenyl)pentaerythritol diphosphite
As clearly seen in the above mentioned detailed description, especially the results of Examples, when improving weather resistance of a thermoplastic elastomer resin, a thermoplastic elastomer containing the alkylbenzoate compound according to the present invention as an ultraviolet absorber exhibits remarkably improved weather resistance and resistance to weather-induced coloring as compared with the case where antioxidants, hindered amine photo-stabilizer, or other ultraviolet absorbers are used. Use of the alkylbenzoate compound yields other improvements, including prevention of blooming, prevention of fogging, prevention of plate-out during processing, and prevention of staining of a processing machine, because pigments which are used are not transferred. | An automobile interior or exterior trim material which is formed of a thermoplastic elastomer composition containing 100 parts by weight of a thermoplastic elastomer and 0.001-10 parts by weight of an alkyl benzoate compound of the following formula (I):
wherein each of R 1 and R 2 is a hydrogen atom, a C1-C8 alkyl or cycloalky; grout, or a C6-C12 aryl, alkylaryl, or arylalkyl group; and R 3 is a C1-C30 alkyl group. The interior or exterior trim material of the invention has improved weather resistance and resistance to weather-induced coloring. | 1 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention generally relates to metal-plated automobile wheels. More specifically, this invention relates to a composite automobile wheel having a permanently attached metal-plated overlay which is formed from a high impact plastic and whose bond strength with the metal plating permits the overlay to be shaped and contoured to closely conform to the shape of the wheel without concern for the deleterious effects of heat and corrosion on the high impact plastic or the integrity of the metal plating bond.
[0003] 2. Description of the Prior Art
[0004] Motor vehicles often include substantial amounts of metal-plated trim elements which provide both decorative and functional purposes. In particular, chrome-plated aluminum wheels have been very popular since the time chromium plating was first introduced, and have recently become particularly fashionable with both sports cars and prestige automobiles. Chrome-plated wheels are often significantly contoured to enhance their effect on the overall appearance of the vehicle by exploiting the highly reflective nature of the chromium surface.
[0005] However, automobile manufacturers have not generally provided chrome-plated cast aluminum wheels as original equipment on their automobiles because the porosity of the cast aluminum makes such wheels very difficult to plate. Moreover, the porosity of cast aluminum wheels results in a somewhat porous chromium plate layer which generally exhibits poor corrosion resistance to the wheel, causing the chromium plating to be susceptible to corrosion. Specifically, it is well known in the art that chrome-plated cast aluminum wheels have been unable to pass the automobile manufacturers' corrosion tests due to the inability of the copper-nickel-chrome layer to effectively cover the porous aluminum cast wheel. As a result, chrome-plated cast aluminum wheels have been provided to the public exclusively by aftermarket suppliers who adapt expensive plating techniques to attempt to save this problem with limited success.
[0006] To obtain better plating results, current plating practices generally entail plating only machined surfaces of a cast aluminum wheel, the machining being intended to “close” the pores in the cast aluminum surface to promote a better subsurface to which the chromium may be plated. However, this approach severely limits the surfaces of a cast aluminum wheel which can be chrome-plated since known machining techniques are incapable of adequately machining deep recesses in cast aluminum wheels, such as the turbine openings formed in “spoke” wheels. Nevertheless, the entire wheel is often chrome-plated, resulting in poor adherence on surfaces which were not machined or inadequately machined, leaving these areas highly susceptible to delamination and corrosion. Chromium plating the entire wheel also incurs up to three pounds of additional weight, which detracts from the weight advantage of cast aluminum wheels.
[0007] In addition to the adverse effects of porosity and resulting corrosion, the adhesive strength of a chromium plating must be sufficient to endure deformation of the wheel as the automobile is driven down the road, or when the automobile is involved in a collision, or strikes road debris, roadway abutments or the like. Such hazards further challenge the ability of the chromium to adhere to the wheel without cracking or delamination. One known approach to avoiding this threat is to provide an ornamental wheel cover which is attached to the wheel so as to partially isolate the wheel cover from wheel deflections. U.S. Pat. No. 3,915,502 to Connell adopts this approach, providing an annular-shaped wheel cover that is permanently attached with double-sided adhesive tape to the wheel midway between the rim and the center hub area of the wheel. The remainder of the wheel cover is spaced apart from the outboard surface of the wheel, presumably to avoid the deleterious effects of heat generated by the tire, the wheel and the brake. However, Connell teachings nothing toward improving the subsurface of a metal-plating to the wheel cover such that the metal-plating might survive an automobile manufacturer's corrosion tests. In addition, the bulky structure taught by Connell almost completely hides or obscures the styling of a wheel, thereby significantly defeating the purpose of using a cast aluminum wheel—that is, the prestigious appeal associated with its appearance.
[0008] As another substitute for directly plating wheels, it is also known in the prior art to use a plastic overlay which is bonded to the outboard surface of the wheel for purposes of appearance and aesthetics. Generally, this approach is taken to allow the wheel to be designed for structural purposes, allowing the wheel's appearance to be determined by the ornamental design of the overlay.
[0009] As taught by U.S. Pat. No. 3,669,501 to Derleth, the ornamental surface of an annular-shaped overlay is a thin plastic cover, preferably formed from acrylonitrile-butadiene-styrene (ABS), which is axially spaced away from the outboard surface of the wheel to provide a cavity between the cover and the wheel into which an adherent polyurethane foam is disposed. Derleth teaches that the polyurethane foam adhesive provides a low-density, semi-resilient reinforcement for the thin gauge plastic cover while also providing sound insulation for tire and wind noise. However, it is understood by those skilled in the art that another reason for spacing the overlay's cover from the wheel surface is to avoid the deleterious effects of heat generated by the wheel and brake which would otherwise distort the plastic cover and delaminate any metal plating applied thereto. This is particularly true in the immediate region of the wheel hub where temperatures tend to be much higher than in the remainder of the wheel. As a result, definite styling and design limitations are associated with the use of the overlay taught by Derleth. Moreover, the styling of the wheel is obscured by the overlay. In addition, Derleth does not teach an overlay with improved adhesion between the overlay and its aesthetic treatments which might successfully pass an automobile manufacturer's corrosion tests.
[0010] Another example of an overlay is taught in U.S. Pat. No. 4,416,926 to Maglio, which discloses adhering a wheel cover to a wheel with a resin matrix containing hollow microspheres. Similar to the teachings of Connell and Derleth, the wheel cover taught by Maglio is also axially spaced away from the wheel to avoid the wheel's potentially high temperatures, particularly near the center of the wheel. U.S. Pat. No. 4,659,148 to Grill emphasizes this concern, teaching an overlay which is attached only to the outer regions of the wheel, while extending radially inward toward the center of the wheel a limited distance. A retainer is provided to space the overlay axially away from the center of the wheel, thus avoiding thermal conduction from the wheel center to the overlay. In contrast to Grill, U.S. Pat. No. 4,682,820 to Stalter teaches a plastic cap which completely covers but is axially spaced from the region of the wheel center. The cap relies upon an interference fit with an annular-shaped overlay to remain attached to the wheel.
[0011] In addition to their styling being significantly limited by the adverse effects of high temperatures, the ornamental plastic overlays of the above prior art all share a common disadvantage in their inability to permanently adhere a metal plating, particularly when exposed to a corrosive environment. Though the prior art fails to emphasize this aspect as a recurring problem, its existence is clear from the fact that automobile manufacturers have not to date provided chrome-plated plastic overlays as original equipment. As with the aforementioned chrome-plated wheels, metal-plated plastic overlays have been unable to pass the automobile manufacturers' corrosion tests, and therefore have been provided to the public exclusively by aftermarket suppliers.
[0012] A wide variety of platable plastics are known. For example, unmodified acrylonirile-butadiene styrene (ABS) has been plated to provide decorative articles such as headlamp surrounds, and plumbing and marine hardware. Unmodified polycarbonate (PC) has been utilized as the substrate for plated motor vehicle door handles. In addition, several other plastics have been successfully plated for various decorative purposes. However, these plastics, even though platable, do not provide a satisfactory substrate if the finished article must be capable of sustaining significant impacts or temperatures. Accordingly, the use of these materials within an automobile is limited. These plated plastics are characterized by a tendency to fail at low energy levels of impact, resulting in the delamination of the chromium plating from its plastic substrate. In addition, as an extreme example, the unmodified ABS may even shatter upon impact. Thus, for a plastic to be suitable as a substrate for a metal-plated wheel cover or overlay, the adhesion between the plating and the substrate must generally have sufficient impact resistance, as well as temperature and corrosion resistance.
[0013] From the above discussion, it can be readily appreciated that the prior art does not disclose a metal-plated cast aluminum wheel whose metal plating is provided uniformly over the surface of the wheel, including the contours and deep recesses of the wheel, while also being capable of passing an automobile manufacturer's corrosion resistance test. In addition, the prior art does not disclose a metal-plated overlay which can be permanently adhered directly to the wheel to closely follow the contours of the wheel while also being resistant to delamination of the metal plating due to corrosion, high temperatures and impact. In effect, the design requirements of such overlays restrict the location of the overlays on the surface of the wheel, while also limiting the appearance of the overlay by requiring that the metal-plated surface be axially spaced and isolated from the outboard surface of the wheel to avoid the adverse effects of the elevated wheel temperatures. Finally, the prior art has not provided a metal-plated overlay which permits the cast aluminum wheel to define the overall styling and structural appearance of the wheel, while the overlay is specifically limited to contributing the reflective character of the wheel for purposes of aesthetics.
[0014] Accordingly, what is needed is a low-cost ornamental metal-plated overlay for an automobile wheel which can be permanently secured directly to the wheel to closely follow the contours of the wheel, without needing to insulate the metal-plated surface of the overlay from the wheel and without needing to drastically limit the location of the overlay such that the overlay is isolated from the center and periphery of the wheel. As a result, styling and design flexibility would be enhanced because the overlay would be capable of closely conforming to the contours of the entire wheel surface. As such, the wheel would be permitted to define the outward styling configuration of the wheel while the overlay provides the aesthetically-pleasing reflective appearance. In addition, a metal plating or colorful paint on such overlay would remain securely adhered to the overlay, even when exposed to adverse physical, chemical and thermal attack.
SUMMARY OF THE INVENTION
[0015] According to the present invention there is provided a method of providing a cast aluminum wheel which has the aesthetic appearance of being metal plated, even in deep recesses in the wheel, wherein the adhesive strength of the metal plating is sufficient to pass an automobile manufacturer's corrosion resistance test. The above appearance is provided by an overlay which is characterized as being a metal-plated plastic panel which is permanently adhered directly to the surface of the wheel and closely follows the contours of the wheel, including deep recesses such as turbine openings in the wheel. The metal plating on the overlay is highly resistant to the adverse thermal environment of the wheel while also providing corrosion and impact resistance which is superior to that of the prior art. Together, the cast aluminum wheel and the metal-plated overlay form a composite metal-plated wheel that can be provided as an integral and permanent unit available as original equipment by automobile manufacturers.
[0016] The metal-plated overlay of the present invention promotes design flexibility in that the overlay is fabricated as a thin panel structure which completely and closely conforms to the contours of a wheel, including the turbine openings in the wheel. The metal-plated exterior surface of the overlay closely follows the contours of the wheel to give the appearance of being the actual surface of the cast aluminum wheel, all without concern for poor adhesion due to porosity of the cast aluminum wheel. In addition, the metal plating is highly resistant to delamination from heat such that there is no need to axially space the metal-plated exterior surface from the outboard surface of the wheel. As a result, the cast aluminum wheel's outboard surface is permitted to define the outward shape and styling of the wheel while the overlay provides the wheel's aesthetically-pleasing reflective appearance without appearing to be a separately formed overlay.
[0017] The composite metal-plated wheel of the present invention includes the typical structure of an automotive wheel, including a central disk portion, or wheel disk, and a rim which circumscribes the disk portion for retaining a tire. The overlay is a metal-plated plastic panel which is attached to the outboard surface of the disk portion. The plastic panel has a pair of oppositely disposed surfaces which form interior and exterior surfaces of the overlay. The interior surface of the overlay mates with the outboard surface of the wheel such that the exterior surface uniformly follows and conforms to the surrounding surface of the wheel surface, including any recesses in the wheel's surface. The thickness of the plastic panel can be as little as about 2 to about 4 millimeters while still providing sufficient impact strength and without concern for the adverse effects that wheel temperatures have on metal plating.
[0018] The plastic panel is preferably formed from a polycarbonate substrate which is modified with less than about 50 percent by weight of acrylonitrile-butadiene-styrene (ABS) and conditioned to increase the amount of exposed ABS at the exterior surface of the plastic panel. The exterior surface is then etched and electrochemically plated with a metal, such as chromium. Due to the thinness of the plastic panel, its metal-plated exterior surface can uniformly and closely follow the contours of the outboard surface of the wheel to provide a pleasing aesthetic effect to the wheel. The material composition of the plastic panel and the preferred plating method permit the exterior surface to be positioned in close proximity to the outboard surface of the wheel while resisiting delamination of the metal plating due to heat.
[0019] According to a preferred aspect of this invention, the metal-plated overlay of the present invention provides an aesthetically pleasing, permanently attached ornamental cover to a cast aluminum wheel without the appearance of being a separately manufactured attachment to the wheel. Because the overlay conforms to the contours of the wheel, the overlay appears to be the actual outboard surface of the cast aluminum wheel. As a result, the aesthetic styling and appeal of the wheel is established by the cast aluminum wheel, whereas the overlay need only contribute the reflective surface to the wheel. Because it is permanently attached and does not appear to be an attachment to the wheel, the overlay is not prone to being stolen or accidentally detached as would be other overlays or conventional wheel covers. Moreover, the wheel can be readily mounted and removed without ever having to tamper with the overlay.
[0020] In addition, the adhesion of the metal plating to the overlay is sufficient to exhibit excellent resistance to both corrosion and heat. Testing has shown that a composite wheel incorporating the overlay of the present invention can successfully pass a typical automobile manufacturer's corrosion test so as to permit its use as an original equipment item. Moreover, the adhesion between the metal plating and the plastic panel exhibits extremely good resistance to high temperatures such that the metal-plated surface need not be spaced away from the surface of the wheel, nor is there a need for an insulating layer of foam between the metal-plated surface and the wheel. Design flexibility of the composite wheel is maximized because of the overlay does not pose any significant styling limitations to the wheel as a consequence of needing to design around the high temperature areas of the wheel.
[0021] Another significant advantage of the present invention is that the overlay can cover substantially the entire visible surface of the wheel, including deep recesses in the surface of the wheel, because the porosity of the cast aluminum wheel is not a factor in the adhesive strength of the metal plating. Whereas in their application due to surface porosity cast aluminum wheels of the prior art were limited as to the coverage of the metal plating or highly susceptible to corrosion and delamination, the overlay of the present invention is able to follow the contours of the wheel, even such features as turbine openings. Yet the overlay adds significantly less weight to the wheel than metal plating the wheel itself, while also being significantly less costly.
[0022] The overlays of the prior art were also unable to provide a closely conforming reflective surface because of the need to carefully provide sufficient spacing or thermal insulation between the metal plating and the surface of the wheel. In contrast, the overlay of the present invention performs well at temperatures which may occur practically anywhere on the surface of the wheel.
[0023] The teachings of the present invention are also applicable to various wheel materials and surface treatments, including steel and magnesium wheels, polished and machined aluminum wheels, textured cast aluminum wheels and painted aluminum wheels. The surface condition of the wheel is not critical as long as an adhesive can form a sufficient bond between the wheel and the overlay.
[0024] Accordingly, it is an object of the present invention to provide an ornamental overlay for a cast aluminum wheel in which the overlay closely conforms to the contours of the wheel, such that the aesthetic styling of the wheel is provided by the cast aluminum wheel while the overlay contributes the reflective surface effect to the wheel.
[0025] It is a further object of the invention that the overlay provide maximum styling and design flexibility as to the locations on the wheel where the overlay can be secured.
[0026] It is still a further object of the invention that the overlay be capable of being permanently secured to the surface of the wheel so as to provide a composite wheel which does not have the appearance of being an assembly of two separately manufactured components.
[0027] It is another object of the invention that the overlay be formed from a suitable material which is both heat and impact resistant, and which can permanently adhere a metal plating.
[0028] It is yet another object of the invention that the overlay can be formed from a thin panel without the need to space or insulate the overlay from the wheel to avoid the adverse effects of high temperatures on the integrity of the ornamental surface.
[0029] It is still another object of the invention that the composite wheel formed with the overlay be suitably reliable in terms of corrosion resistance to be capable of being provided as an original equipment item by automobile manufacturers.
[0030] Other objects and advantages of this invention will be more apparent after a reading of the following detailed description taken in conjunction with the drawings provided.
BRIEF DESCRIPTION OF THE DRAWINGS
[0031] [0031]FIG. 1 is an exploded view of a composite wheel for an automobile, including a hub cover and a metal-plated overlay in accordance with the preferred embodiment of this invention;
[0032] [0032]FIG. 2 is a side view of the composite wheel of FIG. 1;
[0033] [0033]FIG. 3 is a cross-sectional view of the composite wheel along line 3 - 3 of FIG. 2;
[0034] [0034]FIG. 4 is a cross-sectional view of the composite wheel along line 4 - 4 of FIG. 2; and
[0035] [0035]FIG. 5 is a cross-sectional view of a composite wheel in accordance with a second embodiment of this invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0036] With reference to FIG. 1, there is shown an exploded view of a composite wheel 10 for an automobile. The wheel 11 of the composite wheel 10 includes a wheel disk 18 which defines an outboard surface of the composite wheel 10 , a rim 12 which is welded to the perimeter of the wheel disk 18 so as to circumscribe the wheel disk 18 , and a number of recesses, or turbine openings 16 a , through the wheel disk 18 by which a corresponding number of spokes, spiders, or webs 14 a are formed. The wheel 11 may be formed from any suitable material, including steel, magnesium and aluminum. The composite wheel 10 further includes an overlay 20 and a hub cover 13 . The overlay 20 is generally annular-shaped, having a central opening 26 to allow access to a center hub 15 of the wheel 11 . The overlay 20 includes a number of turbine openings 16 b and webs 14 b which correspond to the turbine openings 16 a and webs 14 a in the wheel disk 18 of the wheel 11 .
[0037] As illustrated in FIG. 3, the overlay 20 is preferably a thin gauge panel which is adhered directly to the outboard surface of the wheel disk 18 . Moreover, the overlay 20 corresponds very closely to the contours of the wheel disk 18 . In particular, the webs 14 b and turbine openings 16 b of the overlay 20 closely conform to the webs 14 a and turbine openings 16 a of the wheel 11 , respectively, such that the overlay 20 appears to be integrally formed with the wheel 11 . As such, the wheel 11 defines the structural configuration and styling of the composite wheel 10 , while the overlay 20 provides the visible ornamental affect. In effect, the wheel 11 retains its own aesthetic identity, a particular advantage when the wheel is a commercially popular style, such as a cast aluminum wheel.
[0038] As seen in FIG. 3, the overlay 20 is preferably formed with radially outward and inward, axially-extending flanges 32 and 34 , respectively, which are received in recesses 42 and 44 , respectively, in the surface of the wheel disk 18 . The flanges 32 and 34 and recesses 42 and 44 cooperate to provide a uniform transition from the overlay 20 to the outboard surface of the wheel disk 18 , thereby giving the appearance of a unitary construction. In addition, the overlay 20 is provided with a number of bosses 48 , one of which is located at each web 14 b . Each boss 48 closely engages a corresponding recess 50 formed in the surface of the wheel disk 18 . As shown in FIG. 3, the boss 48 and recess 50 can be secured in cooperative engagement by a fastener 40 , though an adhesive could be used in place of the fastener 40 .
[0039] The bosses 48 and recesses 50 preferably perform two functions. First, two of the bosses 48 serve to locate the overlay 20 in the plane of the wheel disk 18 relative to the center of the wheel disk. Second, the depth of each recess 50 and the length of each boss 48 determine the axial location of the overlay 20 relative to the outer surface of the wheel disk 18 . As a result, the overlay 20 can be accurately positioned on the wheel disk 18 . However, one skilled in the art will recognize alternative methods to locating the overlay 20 relative to the wheel disk 18 , and the teachings of the present invention are not limited to the above method.
[0040] [0040]FIG. 4 illustrates the conformance of the overlay 20 with the webs 14 a of the wheel 11 . The overlay 20 includes side portions 36 which extend axially into the turbine openings 16 a of the wheel 11 . In the preferred embodiment, the ends of the side portions 36 are received in recesses 38 which serve to better secure the overlay 20 within the turbine openings 16 a . However, this tongue-in-groove design can be replaced with intermittent tabs (not shown) which are received in individual slots (not shown) to assist in locating the overlay 20 on the wheel disk 18 .
[0041] The overlay 20 is preferably formed from a thin ABS-modified polycarbonate panel 22 formed by injection molding, though other molding techniques are acceptable. The panel 22 is preferably between about 2 and about 4 millimeters thick to readily blend with the surrounding surface of the wheel disk 18 while affording sufficient strength to the overlay 20 , though one skilled in the art will recognize that greater and lesser thickness will often be acceptable. As can be seen from FIGS. 3 and 4, the overlay's shape and size is specifically designed to correspond to the surface of the wheel 11 to permit the wheel 11 to define the styling of the composite wheel 10 . In that the overlay 20 is not required to be axially spaced from the surface of the wheel 11 , maximum design flexibility can be achieved. The overlay 20 can be permanently adhered directly to the outboard surface of the wheel 11 by a suitable adhesive 30 , such as a silicone or polyurethane adhesive, to form a permanent wheel.
[0042] In the preferred embodiment, the overlay 20 is plated with a suitable decorative treatment, such as a chromium plating 24 . Ideally, the chromium plating 24 is electroplated to the panel 22 such that the overlay 20 is lightweight and has a superior chromium plating-to-plastic bond adhesion. A preferred electroplating process is disclosed in U.S. patent application Ser. No. 07/617,497, filed Nov. 23, 1990, entitled “Method for Electroplating High-Impact Plastics”, and assigned to the assignee of the present invention. The method forms an electroplated ABS-modified polycarbonate article suitable for use in applications which require good impact resistance such as in automotive component applications, wherein the adhesion between an ABS-modified polycarbonate substrate and an electroplated metal is exceptional such that upon impact, the metal plating adheres well without chipping, cracking or delamination from the substrate. In addition, the adhesion between the metal plating and the substrate is highly resistant to temperature and corrosion. While an ABS-modified polycarbonate material is preferred, those skilled in the art will recognize that other polymer materials can also be used, such as unmodified polycarbonate, unmodified ABS, nylon-polycarbonate, polyurethane, and butadiene-loaded ABS.
[0043] In general, the preferred method for forming the chromium plating 24 on the panel 22 is to chemically pretreat or condition an ABS-modified polycarbonate substrate, etch with an acidic solution, electrolessly plate a layer of metal strike, and finally electrochemically deposit the desired chromium plating 24 onto the metal strike. The ABS-modified polycarbonate is a polycarbonate substrate which has been modified with up to about 50 percent by weight of ABS and more preferably between about 15 to about 40 percent by weight.
[0044] The chromium-plated overlay 20 formed according to the preferred method is characterized as having a uniform chromium plating 24 which adheres well to the panel 22 due to the better surface finish obtainable with plastics as compared to cast aluminum. As previously noted, the porosity of aluminum necessitates that an aluminum surface be machined to “close” the exposed pores in order to form an adherent plating. Current machining technology severely limits the ability to obtain a suitable surface quality for plating in such recesses as the turbine openings 16 a and 16 b . This limitation is further complicated by the fact that variations in current density during electroplating causes uneven plating thickness in such deep recesses as the turbine openings 16 a and 16 b . Furthermore, aluminum inherently exhibits variations in surface hardness which prevents the aluminum from being machined to a finish comparable to plastic.
[0045] In contrast, the overlay 20 of the present invention can be formed to provide a surface finish that readily adheres the chromium plating 24 , such that the overlay is highly resistance to impact, corrosion and temperature. The improved adhesion resists delamination from chemical attack by corrosive environments, and particularly the corrosion tests used by automotive manufacturers for purposes of qualifying metal-plated articles for original equipment use. In addition, the overlay 20 is capable of withstanding high temperatures found at the surface of the wheel 11 . As a result, the overlay 20 can be adhered directly to the surface of the wheel 11 , as shown in FIG. 3, without the need to space or insulate the chromium plating 24 from the surface of the wheel 11 to avoid the elevated temperatures associated therewith.
[0046] A second embodiment of the present invention is illustrated in FIG. 5, wherein the overlay 20 is spaced from the outboard surface of the wheel disk 18 , yet is secured to the wheel disk 18 with the fastener 40 as described in the preferred embodiment. The fastener 40 is disposed within a recess 28 formed in the web 14 a of the wheel disk 18 , and the fastener 40 extends through the bosses 48 and 50 to secure the overlay 20 to the wheel 11 . The radially inward and outward flanges 34 and 32 are formed to have extended flanges 46 which abut the bottom of the recess 28 . The recess 28 advantageously reduces the weight of the wheel 11 , while permitting only limited flexing of the overlay 20 relative to the wheel disk 18 . Otherwise, the basic teachings of the preferred embodiment are the same, with the overlay 20 being able to closely conform to the contours of the wheel 11 , including the turbine openings 16 a . The overlay 20 is in intimate contact with the wheel disk 18 at the radially outward and inward flanges 32 and 34 without concern for temperature effects, while the chromium plating 24 is substantially flush with the surface of the wheel disk 18 to give the appearance of a unitary wheel. Accordingly, the overlay 20 of the second embodiment appears to be the outboard surface of the wheel 11 and not an additional attachment.
[0047] A significant advantage of the composite wheel 10 of the present invention is that the overlay 20 can provide an aesthetically pleasing, permanently attached ornamental cover to the wheel 11 without the appearance of being a separately manufactured attachment to the wheel 11 . The overlay 20 closely conforms to the contours of the wheel 11 such that the chromium plating 24 appears to be deposited directly on the wheel disk 18 of the wheel 11 . As a result, the aesthetic styling and appeal of the composite wheel 10 is established by the wheel 11 , whereas the overlay 20 contributes the reflective effect to the composite wheel 10 . The overlay 20 is permanently attached to the wheel 11 and does not appear to be an attachment to the wheel 11 , such that the overlay 20 is not as susceptible to theft or accidental detachment as are prior art overlays and conventional wheel covers. Moreover, because the overlay 20 conforms closely to the wheel 11 , the overlay 20 has a low profile such that the composite wheel 10 can be readily mounted and removed without the overlay 20 being a hindrance.
[0048] In terms of aesthetics and styling, the overlay 20 is preferably formed to closely conform to the contours of the wheel 11 , such as the webs 14 a and turbine openings 16 a illustrated. The good adhesion between the chromium plating 24 and the panel 22 permits the overlay 20 to have intimate contact with the wheel 11 , which facilitates the close conformity desired between the overlay 20 and the wheel 11 . The panel 22 is adhesively bonded directly to the outboard surface of the wheel 11 either with a suitable adhesive 30 as shown, or in any other suitable manner.
[0049] Again, the adhesion between the chromium plating 24 and the panel 22 exhibits extremely good resistance to high temperatures such that no insulating layer of foam is necessary between the chromium plating 24 of the overlay 20 and the wheel 11 , such as that specifically recited by the prior art. This permits the overlay 20 to be formed as the panel 22 which has a low profile and, therefore, does not extend axially outward from the surface of the wheel disk 18 to any significant degree. As a result, the prestige appeal of a cast aluminum wheel can be maintained because the wheel 11 defines the outward shape and styling of the composite wheel 10 while the overlay 20 provides the aesthetically-pleasing reflective appearance. Design flexibility of the composite wheel 10 is then optimized because the overlay 20 does not pose any significant design limitations to the styling of the composite wheel 10 . The chromium plating 24 can be provided near the center hub 15 and deep within the recesses 16 b without concern for high temperatures, improving the appearance and durability of the chromium plating 24 .
[0050] Another significant advantage of the present invention is that the overlay 20 can cover substantially the entire exposed surface of a cast aluminum wheel, including the deep recesses 16 a in the surface of the wheel, because the porosity of the cast aluminum wheel is not a factor in the adhesive strength of the chromium plating 24 . Whereas cast aluminum wheels of the prior art were either limited as to the coverage of the chromium plating 24 or were highly susceptible to corrosion and delamination, the overlay 20 of the present invention is able to follow the contours of the wheel 11 , even such features as the turbine openings 16 a and 16 b.
[0051] While allowing the entire outboard surface of the wheel 11 to have a chrome-plated finish, the overlay 20 of the present invention adds typically less than one pound of weight to the composite wheel 10 , in contrast to the typical two to three pounds added when a metal plating is deposited directly on the wheel 11 itself. The weight of the composite wheel 10 can be further reduced by optimizing the structure of the wheel 11 hidden beneath the overlay 20 , as illustrated in FIG. 5. The plating and material costs according to the teachings of the present invention are also significantly less than that for directly plating a wheel.
[0052] Finally, the adhesion between the chromium plating 24 and the panel 22 is particularly resistant to the temperatures and the corrosive environment associated with automotive applications. Corrosion tests so as to permit its use as an original equipment item sold by automobile manufacturers. Further, as previously noted, the adhesion between the chromium plating 24 and the panel 22 is sufficient such that the panel 22 need not be spaced away from the surface of the wheel disk 18 , nor is there a need for an insulating layer of foam between the panel 22 and the wheel disk 18 . Design flexibility of the composite wheel 10 can be maximized because the overlay 20 does not pose any significant styling limitations to the composite wheel 10 as a consequence of needing to design around the high temperature areas of the wheel 11 .
[0053] Accordingly, the present invention provides a composite wheel which incorporates an overlay that is permanently secured directly to the surface of the wheel such that the overlay appears to be the surface of the wheel and not a separate attachment. As a result, a decorative finish on the overlay appears to be formed on the wheel itself. This is particularly advantageous with hard-to-plate wheel materials, such as cast aluminum. Accordingly, optimization of a wheel's design and styling can be achieved independent of plating limitations.
[0054] While the invention has been described in terms of a preferred embodiment, it is apparent that other forms could be adopted by one skilled in the art. Accordingly, the scope of the invention is to be limited only by the following claims. | A composite vehicle wheel having a disk, a rim circumscribing the disk, and an ornamental metal-plated plastic overlay attached to the outboard surface of the disk. The overlay has a pair of oppositely disposed surfaces which form interior and exterior surfaces of the overlay. The interior surface mates with at least a portion of the outboard surface of the wheel while the exterior surface has metal layer plated thereon. The overlay is formed from a relatively thin plastic panel such that the exterior surface uniformly and closely conforms to the outboard surface of the wheel and the metal layer is substantially flush with the adjacent portions of the outboard surface to provide a pleasing aesthetic effect to the wheel. The integrity of the metal layer is such that the overlay successfully meets corrosion resistance requirements for automobile manufacturers' original equipment. | 1 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims priority of Taiwanese Utility Model Application No. 095219765 filed on Nov. 8, 2006.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] This invention relates to a door lock assembly, more particularly, to a door lock assembly for a fireproof door, which has a cam associated with a handle to transmit movements to a latch operating spindle.
[0004] 2. Description of the Related Art
[0005] According to construction laws, it is required that a fireproof door be installed in a staircase on each floor of a building. In order to prevent fire from moving from one floor to an adjacent floor, the fireproof door is normally closed. However, for emergency exit or safety purposes, the fireproof door is provided with a door latch device which can be readily operated from the inside of the door. Generally, a door latch installed at the inside of the door includes a handle frame installed on the middle of the door. By pressing a handle disposed inside the handle frame, the door can be unlatched and opened. The fireproof door is further provided with a door lock assembly which includes a handle and a key-operated lock. The user may operate the handle and the key-operated lock from the outside of the door to lock or unlock the door. Examples of door lock assemblies for fireproof doors are disclosed in U.S. Pat. Nos. 5,445,423, 5,516,161, 5,658,026, 5,664,816, and 7,181,940.
SUMMARY OF THE INVENTION
[0006] An object of the present invention is to provide a door lock assembly for a fireproof door, which has a simple construction and which can be assembled easily.
[0007] According to one aspect of this invention, a door lock assembly comprises: a housing; a handle connected to the housing; a cam attached to the handle inside the housing and rotatable along with the handle; a rotary drive disposed rotatably in the housing and having a driven part rotated by the cam, and a drive part opposite to the driven part; a latch operator disposed rotatably in the housing and driven by the drive part of the rotary drive; and a latch operating spindle adapted to operate a latch and connected to the latch operator for rotation along with the latch operator.
[0008] According to another aspect of the invention, a door lock assembly comprises: a housing having two aligned support rods; a handle connected to the housing; a latch operating spindle adapted to operate a latch; a cam attached to the handle inside the housing for transmitting rotation of the handle to the latch operating spindle; a key-operated lock unit provided in the housing; a slide plate disposed movably between the cam and the lock unit and movable between a locking position that limits the handle from rotation, and an unlocking position that permits the handle to rotate. The slide plate has two aligned guide holes respectively receiving the support rods in a slidable relationship. A coiled spring is sleeved around one of the support rods and resiliently positions the slide plate.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] Other features and advantages of the present invention will become apparent in the following detailed description of the preferred embodiments of the invention, with reference to the accompanying drawings, in which:
[0010] FIG. 1 is an exploded view of the first preferred embodiment of the present invention;
[0011] FIG. 2 is a perspective view of the first preferred embodiment in which a cover plate is removed;
[0012] FIG. 3 is a plan view of a first preferred embodiment in an unlocking position;
[0013] FIG. 4 is the same view as FIG. 3 , but showing that a cam is rotated;
[0014] FIG. 5 is the same view as FIG. 3 , but showing a locking position of the first preferred embodiment;
[0015] FIG. 6 is an exploded view of the second preferred embodiment in which a slide;
[0016] FIG. 7 is a perspective view of the second preferred embodiment in which a cover plate is removed;
[0017] FIG. 8 is a plan view of the second preferred embodiment in the unlocking position; and
[0018] FIG. 9 is the same view as FIG. 8 , but showing the locking position of the second preferred embodiment.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0019] Before the present invention is described in greater detail, it should be noted that same reference numerals have been used to denote like elements throughout the specification.
[0020] Referring to FIGS. 1 and 2 , there is shown a door lock assembly according to a first embodiment of the present invention, which includes a housing 100 composed of an inner case 1 and an outer case 10 . A cover plate 9 is connected to the inner case 1 . The inner case 1 is provided with two guide rods 11 , two screw rods 12 , two support rods 13 , a handle hole 16 , a passage hole 17 and a tubular flange 19 . The outer case 10 surrounds the inner case 1 , and has a handle hole 102 aligned with the handle hole 16 .
[0021] The door lock assembly further includes a handle 8 , a cam 2 , a rotary drive 3 , a latch operator 4 , a latch operating spindle 5 , a slide 6 , and a key-operated lock unit 7 .
[0022] The handle 8 is connected to the housing 100 , and has a grip portion 84 and a tubular body 85 . The tubular body 85 has one end that is formed with two spaced apart lugs 81 and a groove 82 and that extends through the handle holes 102 and 16 of the outer and inner cases 10 and 1 .
[0023] The cam 2 has two slots 23 for extension of the respective lugs 81 formed at one end of the tubular body 85 . A locking ring 27 is engaged in the groove 82 so that the cam 2 is rotatable along with the handle 8 within the housing 1 . The cam 2 has two opposite tongues 22 extending in an axial direction of the cam 2 . A torsion spring 24 is disposed in the inner case 1 around the tubular flange 19 of the inner case 1 , which in turn extends around the end of the tubular body 85 . The torsion spring 24 has two legs 25 supported on the respective second screw rods 12 . Each leg 25 is engageable with one of the tongues 22 to apply a returning force to the cam 2 . Therefore, when the handle 8 is rotated by an angle, it can return to its original position. A protrusion 21 is formed on a lug portion 20 of the cam 2 .
[0024] The rotary drive 3 is disposed in the housing 100 and has a central hole 31 . The rotary drive 3 is sleeved rotatably around one of the support rods 13 fixed to the inner case 1 substantially in parallel with the latch operating spindle 5 and disposed between the latch operating spindle 5 and the handle 8 . The rotary drive 3 further has a driven part 32 , and a drive part 33 disposed on two sides of the support rod 13 . The driven part 32 overlaps with the lug portion 20 of the cam 2 , and has an engaging groove 320 engaging the protrusion 21 of the cam 2 so that the rotary drive 3 can be rotated by the cam 2 . The drive part 33 also has an engaging groove 330 .
[0025] The latch operator 4 is disposed rotatably in the housing 100 , and is configured as a U-shaped plate having two holes 41 , and a pair of spaced apart lobe portions 40 . The latch operating spindle 5 is fixed in the holes 41 for rotation along with the latch operator 4 . The latch operating spindle 5 passes through a spindle hole 62 in the slide plate 6 , and extends rotatably into the passage hole 17 in the inner case 1 and a first slot 91 in the cover plate 9 . A latch operating end 51 of the latch operating spindle 5 is connected to a latch mechanism (not shown).
[0026] The lobe portions 40 overlap with the drive part 33 of the rotary drive 3 . A protrusion 42 is provided on the lobe portions 40 to engage the engaging groove 330 of the drive part 33 so that the latch operator 4 can be driven by the drive part 33 . Preferably, the protrusion 42 is configured as a pin 42 that has two ends respectively inserted into two holes 43 (only one is shown) in the lobe portions 40 so that the protrusion or pin 42 is held by the lobe portions 40 . The drive part 33 extends inbetween the lobe portions 40 to engage the protrusion or pin 42 .
[0027] The cover plate 9 is further provided with two second slots 92 , and screw holes 96 . The cover plate 9 is secured to the inner case 1 by using screws 94 connected to the respective screw holes 96 and the screw holes in the respective guide rods 11 and screw rods 12 , thereby covering the cam 2 , the rotary drive 3 , the latch operator 4 , and the slide plate 6 . The latch operating end 51 of the latch operating spindle 5 extends through the first slot 91 . Two mounting screw rods 93 extend through the respective second slots 92 and are attached respectively to screw holes in the support rods 13 .
[0028] The housing 100 further has two screw holes 14 (only one is shown), a lock hole 15 and a curve slide hole 18 all of which are formed in the inner case 1 , and a lock hole 101 formed in the outer case 10 . A curve slide hole 95 is formed in the cover plate 9 in alignment with the slide hole 18 .
[0029] The lock unit 7 is disposed in the lock holes 101 and 15 , and has a key plug 71 , a key hole 72 formed in the key plug 71 , two diametrically opposite engaging elements 74 , and a transmitting member 73 rotatable along with the key plug 71 . The transmitting member 73 has a radially projecting transmitting tab 731 . An operating key (not shown) can be inserted into the key hole 72 and a hole 730 of the transmitting member 73 to rotate the key plug 71 and the transmitting member 73 . The engaging elements 74 interlock with respective retaining elements 77 of retaining plates 76 which are secured to the inner case 1 on two sides of the lock hole 15 by means of screws 75 and the screw holes 14 .
[0030] The slide plate 6 is disposed movably between the lock unit 7 and the cam 2 . The slide plate 6 has two aligned guide holes 61 on two sides of the spindle hole 62 . The support rods 13 extend through the respective guide holes 61 such that the slide plate 6 is slidable with respect to the support rods 13 . The spindle hole 62 receives one end of the latch operating spindle 5 . The slide plate 6 further has an engagement part 63 formed on an upper edge thereof, and two abutment parts 64 formed on a lower edge thereof and abutting against the cam 2 .
[0031] The slide plate 6 is resiliently positioned by a coiled spring 54 . The coiled spring 54 is sleeved around the support rod 13 above the latch operator 4 . One end of the coiled spring 54 is in abutment with the cover plate 9 . Another end of the coiled spring 54 has a positioning ring 55 connected thereto. The ring 55 tapers slightly toward the guide hole 61 formed above the spindle hole 62 , and extends partially into the guide hole 61 . The guide hole 61 substantially resembles a figure of eight, and has two inwardly extending projections 611 to engage the positioning ring 55 . The guide rods 11 are disposed on two sides of the slide plate 6 to guide the sliding of the slide plate 6 .
[0032] To place the slide plate 6 in a locking position or an unlocking position, the lock unit 7 controls and moves a pin 78 that extends transversely of the slide plate 6 . The pin 78 has two ends extending movably through the curve slide holes 18 and 95 in the inner case 1 and the cover plate 9 . The slide holes 18 and 95 are proximate to the upper edge of the elide plate 6 . The pin 78 is pushed by the transmitting tab 731 to slide along the slide holes 18 and 95 so as to engage the engagement part 63 of the slide plate 6 (see FIG. 5 ), or to disengage from the engagement part 63 (see FIG. 3 ). When the pin 78 engages the engagement part 63 , the slide plate 6 is in the locking position (see FIG. 5 . When the pin 78 disengages from the engagement part 63 , the slide plate 6 is in the unlocking position (see FIG. 3 ).
[0033] The pin 78 is biased by an elongate spring plate 79 which is disposed in the vicinity of the pin 78 and the slide holes 18 , 95 , and which has two ends respectively supported on the guide rods 11 .
[0034] Referring to FIGS. 3-5 in combination with FIGS. 1 and 2 , when the door lock assembly installed on a door is in its locking position, the key plug 71 and the transmitting member 73 may be rotated by a key (not shown) to push the pin 78 to disengage from the engagement part 63 so that the slide plate 6 permits the cam 2 and the handle 8 to rotate. At this time, the handle 8 can be rotated to move the cam 2 which in turn rotates the driven part 32 of the rotary drive 3 . As a result, the drive part 33 rotates the latch operator 4 and the latch operating spindle 5 as shown in FIG. 4 , thereby unlatching the door and permitting the door to open.
[0035] When the door lock assembly is in an unlocking position, the key plug 71 and the transmitting member 73 may be rotated by the key to push the pin 78 to engage the engagement part 63 (see FIG. 5 ). At this time, because the pin 78 engages the engagement part 63 , the slide plate 6 is limited from moving upward so that the abutment part 64 which is in abutment with the cam 2 prevents the cam 2 and the handle 8 from rotation. As a result, the handle 8 cannot be rotated and the door cannot be unlatched.
[0036] Referring to FIGS. 6-9 , there is shown the second preferred embodiment of the present invention in which the slide plate 6 ′ is used in place of the slide plate 6 of the first preferred embodiment. The slide plate 6 ′ does not have the engagement part 63 and the abutment part 64 . Furthermore, no slide holes 18 and 95 are provided in the inner case 1 and the cover plate 9 . However, the pin 65 is formed on the slide plate 6 ′, and a locking part 66 is provided in the slide plate 6 ′.
[0037] The locking part 66 is configured as a constricted hole section 66 formed in the spindle hole 62 of the slide plate 6 ′. The latch operating spindle 5 further has a detent portion 52 opposite to the latch operating end 51 . The detent portion 52 extends into the spindle hole 62 and is engageable with the constricted hole section 66 . When the lock unit 7 moves the pin 65 , the slide plate 6 ′ is moved between its locking position in which the locking part 66 engages the detent portion 52 (see FIG. 9 ) and its unlocking position in which the locking part 66 disengages from the detent portion 52 (see FIG. 8 ).
[0038] When the door lock assembly is in its unlocking position and when the key plug 71 and the transmitting member 73 are rotated, the transmitting tab 731 moves upward the pin 65 and the slide plate 6 ′ so that the locking part 66 disengages from the detent portion 52 as shown in FIG. 8 . The slide plate 6 ′ is therefore in its unlocking position that permits the latch operating spindle 5 , the latch operator 4 , the rotary drive 3 , the cam 2 and the handle 8 to rotate.
[0039] When the door lock assembly is in its locking position and when the key plug 71 and the transmitting member 73 are rotated, the transmitting tab 731 moves downward the pin 65 and the slide plate 6 ′ so that the locking part 66 engages the detent portion 52 as shown in FIG. 9 . The slide plate 6 ′ is therefore in its locking position that prevents the latch operating spindle 5 , the latch operator 4 , the rotary drive 3 , the cam 2 , and the handle 8 from rotating.
[0040] While the preferred embodiments described hereinbefore are provided with the components, such as, the key-operated lock unit 7 , the pins 78 , 65 and the slide plates 6 , 6 ′, the present invention should not be limited thereto. The present invention may be embodied by dispensing with those components. In this case, the door lock assembly of the present intention is operated without using any key. The latch operating spindle 5 can control a latch (not shown) when operated by the handle 8 through the cam 2 , the rotary drive 3 , and the latch operator 4 .
[0041] While the present invention has been described in connection with what is considered the most practical and preferred embodiments, it is understood that this invention is not limited to the disclosed embodiments but is intended to cover various arrangements included within the spirit and scope of the broadest interpretations and equivalent arrangements. | A door lock assembly includes a cam attached to a handle for rotating a rotary drive in response to rotation of the handle. The rotary drive has a driven part rotated by the cam, and a drive part opposite to the driven part. A latch operator is rotated by the drive part so that a latch operating spindle connected to the latch operator can retract a latch. A slide plate is controlled by a key-operated lock unit to prevent or permit rotation of the cam and the latch operating spindle. The door lock assembly is simple in construction and can be assembled easily. | 8 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation under 35 USC §120 of PCT/EP2008/053766, filed 28 Mar. 2008, which is in turn entitled to benefit of a right of priority under 35 USC §119 from European patent application 07 10 5842.4, filed 10 Apr. 2007. The content of each of the applications is incorporated by reference as if fully recited herein.
TECHNICAL FIELD
[0002] The disclosed embodiments are related to a container unit for the storage and protection of powders and pastes in quantities that are typical for laboratory applications.
BACKGROUND OF THE ART
[0003] In companies with regional or global operations, where new substances are developed and intermediate products as well as samples from production processes are analyzed, a large portion of the time is consumed throughout the entire workflow for the logistics processes that are required in order to dispense these substances in measured doses from source containers into receiving containers at different locations in the laboratory or also in different laboratories that are dispersed worldwide. Particularly in the case of hazardous materials, for example toxic or carcinogenic substances, the required safety measures are very time-consuming and expensive. The cost for a large dosage-dispensing system with an automatic feeder device to move the substance cannot be justified for this kind of application, because such systems are very expensive.
[0004] Therefore, in order to make the workflow more efficient, there is a need for lower-cost dosage-dispensing instruments, so that a larger number of these instruments can be placed in different respective locations. Such dosage-dispensing instruments are particularly advantageous if they are configured as retrofittable units which can be used in high-precision analytical balances. A dosage-dispensing unit is disclosed in French published application 2 846 632 A1 which can be coupled to and uncoupled from an actuating device. The dosage-dispensing device consists in essence of a reservoir container which is connected to the dispensing head. The dispensing head has an outlet opening which can be opened and closed by means of a slider valve. To store the dosage-dispensing unit with the substance contained in it, the entire dispensing head, specifically its openings, can be closed off from the outside with a protective push-on cap. The dosage-dispensing unit as disclosed is suitable for use in so-called compound libraries, i.e. very large substance repositories with defined and controlled climatic conditions.
[0005] However, if the dosage-dispensing units are to be mailed out worldwide, special attention needs to be paid to the protection of the dosage-dispensing unit and the substance contained in it, for example with measures against the penetration of moisture or dirt and to avoid personal accidents which could be caused for example by an unintended escape of toxic substances.
[0006] With the aim of protecting the integrity of the substance and to avoid the risk of personal accidents, the disclosed embodiments therefore have the objective to create a container unit for laboratory substances:
which is safe and simple to handle which protects the substance contained in it from outside influences, for example moisture and contaminants, which prevents personal accidents which could be caused for example by substance escaping from the dosage-dispensing unit, and also prevents unauthorized withdrawals of laboratory substances, and which can be equipped with means to hold information regarding the properties and the condition of the substance contained in the dosage-dispensing unit.
SUMMARY
[0011] The objectives just named are met by a laboratory container unit for the storage and protection of laboratory substances in accordance with the independent device claim.
[0012] A laboratory substance container unit for the storage and protection of laboratory substances includes a protective housing and a dosage-dispensing unit. The dosage-dispensing unit includes a reservoir container and a dispensing head, with the protective housing being releasably connected to the dosage-dispensing unit. For the purposes of transportation and storage, the protective housing encloses at least all of those parts of the dispensing head that are pervious to gas, so that between the dosage-dispensing unit and the protective housing there is an interior space that is sealed off tightly from the outside. To prepare the dosage-dispensing unit for operation, the protective housing can be removed from the dosage-dispensing unit. The protective housing is preferably connected to the dosage-dispensing unit by means of a narrow-pitched screw thread connection, a bayonet coupling with a detent element, or by means of clamp-on closure elements which can be secured with tamper-proof seals. The protective housing has the primary function to form a shield between the surrounding space and the laboratory substance inside the dosage-dispensing unit, in particular to block leak passages in the dispensing head. This barrier is necessary, because it is almost impossible to make the dispensing head permanently air-tight. The potential leak passages which lead through the dispensing head into the reservoir container include in particular the outlet opening as well as bore holes that may be arranged in the dispensing head for the coupling connection to a flow rate control device as well as the connection between the dispensing head and the reservoir container. The protective housing further performs the function of a barrier wall surrounding the dispensing head, so that substance particles which could remain stuck to the outside of the dispensing head in the area of the outlet opening after the dispensing process will remain safely locked away in the interior space of the protective housing and pose no danger to people and the environment.
[0013] In order to make the handling as simple and safe as possible and to provide the required protection for the substance contained inside, there is at least one chamber formed in the protective housing which is filled with a treatment agent. The at least one chamber has a passage opening directed towards the interior space, wherein the passage opening can be closed gas-tight with a chamber closure element. The treatment agent contained in the chamber can preferably be filled into the chamber already during the process of producing the protective housing and can be sealed gas-tight with the chamber closure element.
[0014] The chamber can be configured in the protective housing in such a way that the treatment agent can be filled into the chamber from the outside. The protective housing can also be configured with a plurality of parts. For example chambers that are arranged on the outside of the protective housing and are connected to the interior space by means of passage openings belong likewise to the protective housing.
[0015] While laboratory containers that can be closed gas-tight, wherein for example small bags with desiccant agents are enclosed directly with the substance, are known to be in daily use, the arrangement offers enormous advantages over this conventional storage concept.
[0016] The treatment agent is always spatially separated from the laboratory substance, so that no problems occur with the treatment agent when taking out laboratory substance and in the handling of the laboratory substance container unit. Furthermore, the treatment agent is already in place and in faultless, for example unsaturated condition at the time when the chamber closure element of the protective housing is opened immediately prior to connecting the dosage-dispensing unit with the protective housing, whereby the treatment agent is allowed to take effect. If a chamber closure element in a protective housing is found already open, this would indicate unmistakably that the protective housing was already in use, so that the treatment agent is possibly saturated and therefore no longer effective, and that the inside of the protective housing may possibly be contaminated. It is therefore of advantage if the chamber closure element is designed so that it cannot be closed again. For example, a tear-off tag formed on the protective housing or a tear-off sealing sticker could be used as a chamber closure element.
[0017] Different treatment agents may be employed, depending on the laboratory substance that is to be stored. Substances that are known to be used as treatment agents are for example binding agents such as silica gel, molecular sieve, activated charcoal, and activated clay (potassium bentonite). However, the treatment agent does not necessarily have to be a binding agent. It is also absolutely possible to fill the chamber with treatment agents which for example bind or displace oxygen from the air. When using displacing treatment agents, there is of course an outlet required from the interior space to the outside, for example a pressure relief valve. The treatment agent is preferably present in solid form, but of course it can also be filled into the chamber as a liquid or gas, in which case the chamber closure element and the passage opening has to be designed in accordance with the state of aggregation of the treatment agent. For special solutions it is even conceivable to fill reaction components into the chambers which are intentionally planned to cause a change of the laboratory substance in the reservoir container during the storage time. Such special solutions could be used for example in aging tests, by filling the chamber for example with water or even with an oxygen carrier such as potassium nitrate instead of the treatment agent.
[0018] The passage opening can of course be configured in very different ways. It is preferably designed so that no treatment agent can escape through the passage opening into the interior space, but that the passage opening still allows gas to pass through. When coarse-grain silica gel is used, it is sufficient to use for example a sieve insert, while in the case of finer powders, it is preferred to arrange a gas-permeable membrane or a tissue in the passage opening.
[0019] If the same protective housing is to be used more than once, it can have more than one chamber, with each chamber having its own chamber closure element. In one possible embodiment, each of these chambers can be filled with a different treatment agent, so that the one treatment agent that is specifically suitable for the laboratory substance can be activated by opening the respective chamber closure element. Of course each chamber closure element can be provided with appropriate directions for use. It is of course possible to activate several treatment agents at once by removing more than one chamber closure element.
[0020] To provide a simple way of filling the laboratory substance container unit, specifically its reservoir container, with a laboratory substance, the reservoir container can have a substance-receiving space and a fill opening. The fill opening can be tightly closed with a lid, whereby the substance-receiving space can be tightly sealed against the outside. The connection between the lid and the fill opening is preferably designed so that the lid cannot be opened again, once it has been closed.
[0021] To make it easy to fill the laboratory substance into the container unit, the lid is preferably not part of the protective housing, so that the lid and the protective housing can be connected independently of each other to the dosage-dispensing unit.
[0022] The lid can likewise include at least one lid chamber. The latter has a lid chamber passage opening which in the closed condition of the reservoir container is directed towards the substance-receiving space. The lid chamber passage opening can likewise be closed up gas-tight with a chamber closure element. Everything said herein about a chamber or a plurality of chambers and their chamber closure elements is analogously applicable for the lid chambers.
[0023] Especially in large substance storage systems, the advantage of being able to monitor the stored substances individually cannot be overestimated. In order to make it possible to check the condition of the treatment agent or of the laboratory substance, there can be at least one indicator and/or sensor arranged in the at least one chamber and/or in the interior space and/or, if applicable, in the lid chamber. The sensor can be a humidity sensor, a pressure sensor, a gas sensor, or an optical sensor.
[0024] The at least one sensor preferably has a wireless or wire-bound connection to a monitoring unit that is arranged inside or outside the laboratory substance container unit. The externally arranged monitoring unit can be connected to the substance storage management system. As soon as irregularities occur with a laboratory substance container unit, it is conceivable that for example the robot that is tied into the substance storage management system could automatically be dispatched to fetch the laboratory substance container unit in question and put it into an output or disposal station.
[0025] In case the chamber and, if applicable, the lid chamber is equipped with an observation window and an indicator, the condition of the treatment agent or the conditions existing in the interior space of the laboratory substance container unit can also be verified optically. Such an indicator can be a treatment agent such as for example silica gel, which changes its color from blue to red as soon as it has reached a certain degree of moisture saturation. The monitoring unit described above could in this case monitor the condition of the treatment agent by means of an optical sensor, where the optical sensor would not even need to be arranged in the interior of the laboratory substance container unit, but could register the color change through the observation window. The optical sensor can in this case be permanently installed in the parking location of a laboratory substance container unit.
[0026] Of course, the reservoir container and/or at least a housing component of the dispensing head and/or the protective housing can be made of a transparent material. This provides a problem-free way to check how much substance remains in the laboratory substance container unit. It can further be verified whether the dispensing head is still tightly sealed or whether laboratory substance is already present in the interior space of the protective housing, so that there will be a danger of contamination when the protective housing is removed.
[0027] As a means to protect the laboratory substance filled into the laboratory substance container unit from harmful radiation from the environment, the transparent material can have filter properties for certain wavelengths of light, or it can be coated with a material having such filter properties.
[0028] If the coated material with the filter properties is arranged in the interior space, it can also have the properties of an indicator. For example, if the relative air humidity in the interior space is too high, the coating material could change color as a result of the humidity or it could even loose its transparency. The coating material itself can also absorb part of the humidity and can thus serve as a treatment agent.
[0029] In an advantageous embodiment, the reservoir container further has scale markings, so that the substance quantity in the reservoir container can be verified by simple visual observation.
[0030] To facilitate handling, the protective housing preferably has a flat bottom which forms a stable base for the laboratory substance container unit to stand on. The stable standing base makes it safe and easy to fill the reservoir container with a laboratory substance.
[0031] The reservoir container and the dispensing head of the dosage-dispensing unit do not necessarily have to be connected in a way that allows them to be separated from each other. If a lid and a fill opening are provided, the reservoir container and the dispensing head can also be integrally connected in one piece.
[0032] In addition to the chambers, the protective housing can have at least one gas inlet and/or a vacuum connection which is equipped with a check valve and can be connected to a gas supply source or a vacuum pump. The connection of the protective housing to the gas supply source or the vacuum pump can be maintained during an initial storage period or can be in place for only a short period for filling or evacuating. With the gas supply or the vacuum pump, the interior space of the protective housing can be filled with either a gas atmosphere or with a sub-ambient atmospheric pressure, which also propagates through the dispensing head into the reservoir container and replaces the air in the dosage-dispensing unit. This allows for example the useful life of the treatment agent in the at least one chamber to be influenced. A sub-ambient atmospheric pressure or partial vacuum in the protective housing and in the dosage-dispensing unit can function as an additional safety measure, because in case of a leak, air will penetrate into the laboratory substance container unit, but no substance will be able to escape to the outside. A hermetic (gas-tight) closure is necessary in order to be able to maintain the gas atmosphere or the partial vacuum in the interior of the container unit. The container unit as well as the reservoir container will of course have to be designed to have sufficient strength to withstand the pressure.
[0033] In addition to or instead of the gas connection, the protective housing can further contain at least one gas cartridge which can be actuated from the outside to flood the interior space with gas. The actuation from the outside implies that the dosage-dispensing unit is first covered with the protective housing, and the valve of the gas cartridge is operable for example through a push button or rotary knob that is accessible from the outside. Depending on its design, the valve of the gas cartridge can be opened irreversibly, or it can be capable of being closed again. If the valve of the gas cartridge can be closed again, this makes it possible that when the protective housing is removed more than once, the interior space can be flooded with gas again each time after the laboratory substance container unit has been reassembled. As an advantageous feature, there should be an opening with a check valve, so that the air displaced by the gas of the cartridge can escape from the interior space to the outside. Such an opening can also be represented by the connection between the protective housing and the dosage-dispensing unit if the housing expands under the inside pressure to such an extent that during a short time a leak will occur through the connection, so that the excess pressure in the interior space can be released through this leak.
[0034] In a further embodiment, there can be a means of identification arranged on the reservoir container and/or on the dispensing head and/or on the protective housing. This identifier means is preferably an RFID tag, a barcode or matrix code label, or a printed or handwritten adhesive label.
[0035] As a further safety element, the laboratory substance container unit can be sealed with a tamper-proof security label or tamper-proof seal, which is designed so that it has to be visibly broken in order to remove the dosage-dispensing unit from the protective housing.
[0036] If the protective housing has a cup-shaped configuration, the dosage material which may stick to the outside of the dispensing head will collect particularly in the interior space. If this is the case, an insert which holds the laboratory substance particles back may be arranged in the interior space of the protective housing. Such an insert could be for example a felt insert or a micro fiber insert which electrostatically attracts the laboratory substance particles. Of course, one could also use other kinds of inserts such as a moist sponge, a suction device, rotating cleaning brushes and the like.
[0037] Of course, the handling of the laboratory substance container unit described above can be automated by means of a laboratory robot. To implement this concept, the laboratory robot could perform the processes that will now be described.
[0038] In a method to fill, transport and store a laboratory substance container unit:
the reservoir container of the dosage-dispensing unit to which the protective housing is connected as a standing base and whose fill opening at the top is open, is filled with a laboratory substance; if applicable, the chamber closure element of the lid chamber passage opening is removed or opened, and the fill opening is closed with the lid; the laboratory substance container unit is appropriately identified, possibly sealed, and put into storage or sent to its destination.
[0042] In a method to dispense substance from a filled laboratory substance container:
the protective housing is removed from the dosage-dispensing unit, while the fill opening at the top remains closed with the lid; the dosage-dispensing unit is connected to an actuating device and is moved into position above a receiving container; the dosage-dispensing process is started; after the prescribed one or more substance quantities have been dispensed into one or more receiving containers, the dosage-dispensing unit is removed from the actuating device, the chamber closure element of at least one chamber is removed or opened, and the dosage-dispensing unit is connected again to the protective housing; and the laboratory substance container unit is returned to storage or is disposed of.
[0048] As has been described farther above, there can be a monitoring unit for the surveillance of one or more laboratory substance container units. A method to monitor a laboratory substance container unit which has been filled and put into storage can have the following steps:
a measurement signal connection from the sensor to the monitoring unit is maintained continually or periodically, or is initialized by way of a user input; measurement signals delivered continually or periodically or at one time by the sensor are received and registered by the monitoring unit; at least one measurement signal received by the monitoring unit, or a measurement value obtained from the measurement signal, is compared to at least one threshold value that is stored in the monitoring unit; if the threshold value is found to be exceeded, a warning signal is transmitted to an output unit that belongs to the monitoring unit, or to the indicator.
[0053] As can be concluded from the preceding description, the indicator is not necessarily a substance which indicates a change for example by a turn in color. An indicator can also be an electronic component which includes a monitoring unit and an output unit as well as possibly a sensor. The threshold value represents a border of a kind where the laboratory substance contained in the laboratory substance container unit can be negatively affected when the value is exceeded. For example, it is possible that in a certain pulverous laboratory substance a relative humidity of 0% to 15% in the interior space has no influence on the ability of the substance to flow freely, but that individual powder particles will begin to stick together as soon as a value of 15% is exceeded. The threshold value in this example would thus be 15%.
[0054] As a further possibility, a limit value could be defined, for example a maximally permissible temperature, where the total destruction of the laboratory substance will have to be assumed if the limit has been exceeded. As a second example if a threshold value is set at a lower temperature than the limit value at which the laboratory substance begins to break up, it would be possible to calculate the remaining useful lifetime for the laboratory substance by keeping track of multiple incidents when the threshold value was exceeded and for how long, and by keeping a running cumulative total of the time during which the temperature was above the threshold.
BRIEF DESCRIPTION OF THE DRAWINGS
[0055] Details of the laboratory substance container unit will become apparent from the description of the embodiments illustrated in the drawings, wherein identical parts are identified with identical reference numerals and wherein:
[0056] FIG. 1 is a three-dimensional view of a laboratory substance container unit, wherein the dosage-dispensing unit is partially pulled out of the protective housing;
[0057] FIG. 2 shows an empty laboratory substance container unit in sectional view in the assembled state, with a chamber that is filled with a treatment agent and closed up;
[0058] FIG. 3 shows a filled laboratory substance container unit in sectional view in the assembled state, ready for storage or for transportation, wherein the lid has a lid chamber;
[0059] FIG. 4 shows a filled laboratory substance container unit in sectional view, which is substantially analogous to the laboratory substance container unit of FIG. 3 , but is equipped with an automatic chamber closure element;
[0060] FIG. 5 shows a filled laboratory substance container unit in sectional view, which is substantially analogous to the laboratory substance container unit of FIG. 3 , but is equipped with a first embodiment of a rotatable chamber closure element; and
[0061] FIG. 6 shows a filled laboratory substance container unit in sectional view, which is substantially analogous to the laboratory substance container unit of FIG. 3 , but is equipped with a second embodiment of a rotatable chamber closure element.
DETAILED DESCRIPTION OF THE EMBODIMENTS
[0062] FIG. 1 illustrates a laboratory substance container unit 1 according to a first embodiment. A dosage-dispensing unit 2 with a reservoir container 3 and a dispensing head 5 is shown partially pulled out of a protective housing 15 . The reservoir container 3 , which looks like a small storage hopper for pourable bulk materials and which has a cylindrical upper part 8 and a funnel-shaped bottom part 9 , consists preferably of a transparent material and has scale markings 50 , so that the quantity of laboratory substance in the reservoir container 3 can be estimated easily.
[0063] In reference to the spatial orientation of the laboratory substance container unit 1 or one of its components, expressions such as “upper part”, “bottom part”, “above”, “below”, etc. always relate to the orientation of the dosage-dispensing unit in its operation-ready state for the dispensing of a substance, where the reservoir container is on top and the dispensing head is at the bottom.
[0064] A lid 11 over the top of the reservoir container 3 closes off a wide fill opening 10 . In the illustrated example, the lid 11 has an internal thread, which engages a first external thread 4 on the reservoir container 3 . The lid 11 can further contain a seal ring (not shown) or another suitable means to hermetically seal the reservoir container 3 from the outside environment. At its lower end, the reservoir container 3 is connected to the dispensing head 5 by way of a second external thread 12 which engages an internal thread in the dispensing head 5 . Of course, the dispensing head 5 and the reservoir container 3 can also be integrally connected with each other as one piece. The reservoir container 3 has a protruding shoulder 13 and a third external thread 14 at the transition from the cylindrical upper part 8 to the funnel-shaped lower part 9 . The protective housing 15 , with a matching internal thread 16 , can be screwed tightly against the shoulder 13 . To form a hermetic seal between the dosage-dispensing unit 2 and the protective housing 15 , a seal ring (as shown in FIGS. 2 and 3 ) could be inserted between the shoulder 13 and the rim of the cup-shaped protective housing 15 . The protective housing 15 could also be equipped with a gas- or vacuum connection 51 , whereby a gas supply source (not shown) or a vacuum pump could be connected by way of a valve, in order to create inside the protective housing 15 either a gas atmosphere or a sub-ambient pressure level, which would spread through the gas-permeable passages in the dispensing head 5 all the way into the reservoir container 3 .
[0065] The gas-permeable passages in the dispensing head 5 are in particular caused by the closure element 6 which is movably constrained in the housing of the dispensing head 5 and which serves to variably regulate the orifice aperture of an outlet opening.
[0066] As a means to uniquely identify the dosage-dispensing unit, the latter can be equipped with an identifier means 19 , for example a barcode label or an RFID tag. As a preferred concept however, all separable components such as the dispensing head 5 , the reservoir container 3 , the lid 11 and the protective housing 15 carry an identifier means 19 , so that they can be identified unambiguously as belonging to each other, and that no dangerous cross-contamination can occur as a result of mix-ups.
[0067] The protective housing 15 further contains a chamber 17 , which is indicated with a broken line. The interior of the chamber 17 can be viewed from the outside, as the protective housing 15 has a transparent window 18 in the area of the chamber 17 .
[0068] FIG. 2 shows an empty laboratory substance container unit 21 in sectional view in the assembled state. The laboratory substance container unit 21 represents a second embodiment which is nearly identical with the laboratory substance container unit of FIG. 1 , however with the important exception that the reservoir container 23 is closed at the top. The advantage provided is that there is neither a fill opening nor a lid and therefore the risk of an atmospheric leak at the lid or an unintentional lifting of the lid is avoided. On the other hand, however, the process of filling the laboratory substance into the reservoir container 23 is more complicated than with the container unit of FIG. 1 . For the filling process, the dosage-dispensing unit 22 has to be separated from the protective housing 35 and turned upside down, the dispensing head 5 has to be taken off, and the laboratory substance has to be filled through the smaller and less practical opening at the bottom.
[0069] FIG. 2 makes the leak passages or ring gaps between the housing of the dispensing head 5 and the closure element 6 even more evident than FIG. 1 .
[0070] The protective housing 35 includes the chamber 17 which has already been described in the context of FIG. 1 . Between the interior space 28 of the protective housing 35 and the chamber 17 , there is a passage opening 29 which is closed up gas-tight with a chamber closure element 30 . The chamber closure element 30 shown in FIG. 2 is a foil sticker which covers and seals all of the holes of the sieve-like passage opening 29 . The chamber 17 is filled with a treatment agent 52 , for example the desiccant silica gel. By simply tearing off the chamber closure element 30 , the passage opening 29 is set free, so that the effect of the treatment agent 52 can spread into the interior space 28 and through the leaks of the dispensing head into the dosage-dispensing unit 22 . The tearing-off or opening of the chamber closure element 30 does not necessarily have to be performed manually, but with a suitable design configuration it can also occur automatically in the process of joining the protective housing 35 to the dosage-dispensing unit 22 . For example a hook (not shown in the drawing) formed on the dispensing head 5 could serve to tear off a foil sticker or lift off a cover lid. Through the transparent window 18 , it is possible to check whether the desiccant silica gel, which is mentioned here as an example, has turned color, i.e., whether or not it is saturated with moisture. Of course it is also possible, depending on the treatment agent 52 , to add specific indicators (not shown in FIG. 2 ) to the treatment agent. In laboratory substances that release acidic vapors, the treatment agent 52 could for example be a calcium-containing substance, while the indicator is for example a litmus paper strip.
[0071] Of course, as an alternative or in addition to the transparent window 18 , one could use at least one sensor 55 and at least one monitoring unit 56 which is connected to the sensor 55 . The locations where the sensor 55 and the monitoring unit 56 are arranged are irrelevant. The sensor 55 only has to meet the requirement that it can detect the condition that is of interest in the interior of the laboratory substance container unit 21 , more specifically that it can measure the parameter that is indicative of said condition, for example the relative humidity. The sensor 55 can be arranged for example inside the reservoir container 23 or inside the protective housing 35 and can be connected to the monitoring unit 56 , which is arranged outside, by way of a physical connection 57 or a wireless connection 57 . Furthermore, the sensor 55 can also be arranged on the outside, for example in the vicinity of the transparent window 18 , to detect for example the fill level of the treatment agent 52 contained in the chamber 17 or a color change of the indicator. Of course, the sensor 55 as well as the monitoring unit 56 can be incorporated in the protective housing 35 .
[0072] The bottom 27 of the protective housing 35 is preferably flat, in order to form a stable standing base or foot for the laboratory substance container unit 21 . Of course, the protective housing 35 can include mechanical and electrical coupling elements, for example connector sockets or coupling projections. By means of these coupling elements, the laboratory substance container unit 23 can be connected conveniently and safely with other laboratory apparatus such as a multi-unit receiving rack for laboratory substance container units 21 or with a handling system such as a laboratory robot.
[0073] FIG. 3 shows a laboratory substance container unit 101 in sectional view in the assembled state, ready for storage or transportation. The reservoir container 123 of the dosage-dispensing unit 102 is filled with a laboratory substance 150 . As in FIG. 1 , the reservoir container 123 has a fill opening which is closed with a lid 111 . A lid chamber 131 is formed in the lid 111 . Between the lid chamber 131 and the inside of the lid 111 , there is a lid chamber passage opening 134 , which is sealed gas-tight by means of a lid closure element 135 . Arranged in the lid chamber 131 are a pouch 133 which is filled with a treatment agent and is gas-permeable, and an indicator 132 . Due to the fact that the lid 111 is made of transparent plastic, the indicator 132 can be conveniently observed from the outside.
[0074] In the protective housing 115 two chambers 117 , 118 are formed, each of which has a passage opening 129 . One chamber 118 is still sealed gas-tight by means of a chamber closure element 130 , while the other chamber 117 is open towards the interior space 128 of the protective housing 115 . In addition, to allow the chambers 117 , 118 to be filled in a simple manner, each of the chambers 117 , 118 also has a fill opening which is sealed gas-tight with a seal plug 119 . This seal plug 119 can also be bonded with an adhesive or welded to the protective housing 115 , so that it cannot be opened.
[0075] The protective housing 115 may contain an insert 155 which binds the laboratory substance particles. Such an insert 155 could be for example a felt insert or a micro fiber insert which electrostatically attracts the laboratory substance particles.
[0076] FIG. 4 shows a filled laboratory substance container unit 201 in sectional view, with a dosage-dispensing unit 102 that is identical to the dosage-dispensing unit shown in FIG. 3 , so that is does not need to be described again in detail. The protective housing 215 shown in FIG. 4 has an automatic chamber closure element with a valve body 242 . A ring-shaped chamber 218 is formed in the floor area of the protective housing 215 and filled with a treatment agent 252 . Several passage openings 229 extend radially from the chamber towards the center of the protective housing 215 . Arranged in the middle of the ring-shaped chamber 218 is the valve body 242 , which is slidable within a range of linear movement that is limited by end stops formed on the valve body 242 . The valve body 242 is pushed by a spring 241 against the direction in which the dosage-dispensing device 102 is installed in the protective housing 215 . The valve body 242 has several windows 243 , 244 which are configured and matched to the passage openings 229 in such a way that the gaseous medium in the interior space 228 can freely circulate between the chamber 218 and the interior space 228 as soon as the dosage-dispensing unit 102 is firmly connected to the protective housing 215 . The reason why this is possible is that the valve body 242 can be pushed by a part of the dosage-dispensing unit 102 , for example the dispensing head, against the biasing force of the spring 241 . As soon as the protective housing 215 is removed from the dosage-dispensing unit, the spring 241 will push the valve body 215 into a closed position, where the passage openings 229 of the chamber 218 are covered by wall portions of the valve body 242 . Of course, leakage paths in the form of ring-shaped gaps between the chamber and the valve body can be sealed gas-tight by means of appropriate sealing means such as O-rings.
[0077] Preferably, there is a first indicator 245 arranged in the chamber 218 , to indicate the condition of the treatment agent 252 . A second indicator 246 provides the capability to monitor the interior space 228 . If the two indicators 245 , 246 of an assembled laboratory substance container unit 201 indicate different conditions after an extended storage period, it is safe to assume that the valve body 242 is not functioning correctly so that the treatment agent cannot have its intended effect.
[0078] FIG. 5 shows a filled laboratory substance container unit 301 in sectional view, with a dosage-dispensing unit 102 that is identical to the dosage-dispensing unit shown in FIG. 3 . The protective housing 315 illustrated in FIG. 5 is equipped with a first embodiment of a rotatable chamber closure element that is manually operable from the outside. Inside the protective housing 315 , a chamber 318 is formed which is of cylindrical shape. Passage openings 329 are arranged between the chamber 318 and the interior space 328 of the protective housing 315 . The chamber 318 is accessible from the outside in one area of the protective housing 315 , meaning that the cylindrical shape of the chamber 318 extends to the circumference of the protective housing 315 . In the cylindrical chamber 318 , a cup-shaped shell 340 is arranged so that it can be turned between a closed position and an open position. The shell 340 has several windows 343 which are configured and matched to the passage openings 329 in such a way that the gaseous medium in the interior space 328 can freely circulate between the chamber 318 and the interior space 328 as soon as the shell 340 has been turned to the open position by means of a handle 341 . The shell 340 is filled with a treatment agent 352 .
[0079] The first advantage of a chamber closure element that can be operated form the outside is that the activation of the treatment agent 352 to take effect can be delayed at the discretion of the work user until after the laboratory substance container unit 301 has been assembled. The second advantage of this embodiment is that treatment agent 352 can be exchanged without having to separate the dosage-dispensing unit 102 from the protective housing 315 . The shell 340 can be pulled out of the chamber 318 for this purpose, the treatment agent 352 can be exchanged, and the shell 340 can be set back into the chamber 318 . Of course, leakage paths in the form of ring-shaped gaps between the chamber and the shell 340 can be sealed gas-tight by means of appropriate sealing means such as O-rings, and the shell 340 can be secured in the protective housing 315 .
[0080] FIG. 6 shows a filled laboratory substance container unit 401 in sectional view, with a dosage-dispensing unit 102 that is identical to the dosage-dispensing unit shown in FIG. 3 . The protective housing 415 illustrated in FIG. 6 is equipped with a second embodiment of a rotatable chamber closure element that is manually operable from the outside. Inside the protective housing 415 , more specifically in the area of the floor, a ring-shaped chamber 418 is formed which is open from below. A cassette 440 of ring-shaped configuration fits into the ring-shaped chamber 418 and is rotatable about its central axis between a closed position and an open position. The ring-shape cassette 440 has several cavities 445 that are filled with a treatment agent 452 . The cassette 440 is held in the chamber 418 of the protective housing 415 by means of a spring 451 and a rotary bearing 455. Passage openings 429 are arranged in at least a sector of the ring-shaped border surface between the chamber 418 and the interior space 428 of the protective housing 415 . The ring-shaped cassette 440 has several windows 443 which are configured and matched to the passage openings 429 in such a way that the gaseous medium in the interior space 428 can freely circulate between the chamber 418 , more specifically at least one of the cavities 445 , and the interior space 428 , as soon as the cassette 440 has been turned to the open position by means of a handle 441 .
[0081] Although the invention has been presented though specific examples of embodiments, there are obviously numerous further variations that could be created from a knowledge of the present invention, for example by combining the features of the individual embodiments with each other and/or by exchanging individual functional units of the embodiments against each other. For example, the monitoring unit shown in FIG. 2 as well as the sensor associated with it, or possibly several sensors, which are used to measure different parameters of the atmosphere in the interior space, such as relative humidity, temperature, pressure and the like, can also be used in all of the other laboratory substance container units. Further embodiments of the dosage-dispensing head or further chamber closure elements are conceivable as well as different possible form-locking connections between the dosage-dispensing unit and the protective housing. | A container unit for the storage and protection of laboratory substances includes a protective housing and a dosage-dispensing unit. To make the dosage-dispensing unit ready for use, the protective housing is removable. As a means to optimize the simplicity and safety of handling the unit and to achieve the required protection for the laboratory substance contained in it, at least one chamber is formed in the protective housing and filled with a treatment agent. The at least one chamber has a passage opening directed towards the interior space, with a chamber closure element allowing the passage opening to be closed gas-tight. The treatment agent inside the chamber can preferably be filled into the chamber and sealed off gas-tight with the chamber closure element already during the process of manufacturing the protective enclosure. | 1 |
BACKGROUND OF THE INVENTION
This invention relates to coating compositions, and more particularly to water based silicone coating compositions that offer superior coating properties, resistance to high temperatures and to the effects of corrosive environments and durability. The present invention provides water based silicone coating compositions, methods for producing such compositions, as well as high temperature heat exchangers whose surfaces are coated with such water based silicone coating compositions.
Silicone resins are known to demonstrate endurance towards environmental conditions such as weathering and extreme heat and cold. For this reason these resins have been found to be particularly useful in the paint industry.
Previously, silicone resins were made available to formulators in organic solutions. In particular, the resin consisted of so many parts by weight of silicone solids in an organic solvent such as xylene or toluene. However, due to increased concerns regarding: the suspected health hazards to persons exposed to such solvents; environmental considerations and the mandatory use of costly and burdensome pollution abatement procedures and equipment; and escalating costs for organic materials, the use of such organic solvents has been discouraged. As a result, suppliers of these silicone resins have worked towards developing silicone resin systems that are water based and therefore not dependent upon organic solvents.
Yet, such silicone resins which have been found to be particularly useful in the paint industry have often been found to be immiscible or otherwise incompatible with aqueous coating compositions. For those silicone resins which can be made part of water based emulsions which can then form the basis of a paint or coating composition, the ability of these coatings to generally match the performance (e.g., coating properties) of other temperature-resistant protective coatings is oftentimes not realized. Moreover, such compositions do not serve to adequately protect the underlying substrate from the effects of corrosive environments.
For devices such as high temperature aluminum heat exchangers which have an intricate network of passages therethrough and which are oftentimes subjected to corrosive environments, the deficiencies of prior art water based coating compositions take on significant proportions.
It is, therefore, an object of the present invention to provide water based silicone coating compositions that offer superior coating properties and resistance to high temperatures.
It is another object of the present invention to provide novel coating compositions that exhibit durability and resistance to the effects of a corrosive environment.
It is yet another object to provide a process for producing such water based silicone coating compositions.
It is still another object of the present invention to provide a high temperature heat exchanger whose surfaces are coated with such water based silicone coating compositions.
SUMMARY OF THE INVENTION
The present invention therefore relates to a high temperature coating composition. The coating composition is comprised of: a silicone resin emulsion; a non-water reactive filler material having a laminar structure; a water soluble nonionic surfactant; and water.
The present invention also relates to a process for producing a high temperature coating composition as described above.
The present invention further relates to a high temperature heat exchanger whose external and intricate internal surfaces are coated with a coating composition as described above.
The foregoing and other features and advantages of the present invention will become more apparent from the following description.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The coating compositions of the present invention are useful in a wide variety of applications, including use as high temperature protective coatings for aluminum parts used in the transportation industry, such as high temperature aluminum heat exchangers.
The inventive coating compositions generally will have a total weight percent solids content of approximately 30.4 to 55.7%; a pH range of 6.0 to 8.0; a viscosity of approximately 20 to 40 seconds as measured by a No. 1 Zahn Cup; a density of approximately 1.08 to 1.18 grams per cubic centimeter (g/cm 3 ); a volatile organic compounds content of less than 200 grams/liter; and a filler material (e.g. pigment) to resin solids (e.g. binder) ratio of approximately 1.0 to 2.2 through 1.0 to 4.2. The filler material to resin solids ratio indicates the quantity by weight of resin used with a specified amount of a particular filler material.
In general, the coating compositions of the present invention contain a silicone resin emulsion; a non-water reactive filler material having a laminar structure; a water soluble nonionic surfactant; and water.
The emulsion functions as a high heat resistant binder for the filler material and generally will have a total silicone resin solids content of approximately 38 to 82% by weight. The silicone resin emulsion is comprised of 100 parts by weight of (i) at least one silicone resin having one or more organic side groups attached such as phenyl, methyl, trifluoropropyl and/or vinyl moieties; (ii) an anionic surfactant effective for dispersing the resin in a water based emulsion and for binding the resin or particulate phase and the water or continuous phase; and (iii) an amount of water effective for providing a preselected silicone resin solids content by weight of the emulsion. The emulsion might also contain trace amounts of volatile organic compounds such as xylene and/or toluene present as a result of the manufacturing process.
Silicone resins, which may be used in the emulsion of the present inventive coating composition, include optionally crosslinked resins comprising units selected from the group consisting of R x SiO y where x is 3, 2 or 1 and y is 0.5, 1.0 or 1.5 respectively, and where the R groups are phenyl, methyl, trifluoropropyl and/or vinyl. A typical number average molecular weight and weight average molecular weight of such resins are 420 and 2190, respectively. Preferred silicone resins include lightly crosslinked or soft phenylmethyl silicone resins and moderately to highly crosslinked or medium-hard phenylmethyl silicone resins. The most preferred silicone resin is medium-hard phenylmethyl silicone resin where an increase in the hardness and fluid resistance of the cured inventive coating composition has been observed when this moderately to highly crosslinked resin is used.
Anionic surfactants suitable for use in the silicone resin emulsion of the present inventive coating include sodium lauryl sulfate, sodium linear alkyl benzene sulfonate, triethanol amine linear alkyl benzene sulfonate, sodium alpha olefin sulfonate, ammonium alkyl phenol ethoxylate sulfate, ammonium lauryl ether sulfate, ammonium alkyl ether sulfate, dialkyl ester of sodium sulfosuccinic acid, sodium cumene sulfonate, and ammonium xylene sulfonate. The preferred anionic surfactant is sodium lauryl sulfate.
It will be recognized by those skilled in the art that the water used in the silicone resin emulsion of the present inventive coating is preferably distilled or deionized water.
The preferred silicone resin emulsion is comprised of (i) from 48 to 72 wt. % soft or medium-hard phenylmethyl silicone resin; (ii) from 0.01 to 1.0 wt. % sodium lauryl sulfate; and (iii) from 52 to 27 wt. % water, based on the total weight of the emulsion. The average viscosity of the preferred silicone resin emulsion is from about 40 to about 180 centipoises as measured in accordance with Method B of ASTM D 1084 using a Brookfield LVF. The preferred silicone resin emulsions are available from Dow Corning Corporation, Midland, Mi., under the product designations Dow Corning® 1-0468 resin emulsion and Dow Corning® 1-0469 resin emulsion.
The non-water reactive filler material of the present inventive coating has a laminar structure and functions to form a barrier from corrosive elements thereby protecting the substrate and serves to improve coating properties. Filler materials contemplated by the present invention include pigments in the form of a paste containing flake metal or mineral and a dispersant. These pigments in addition to functioning as a barrier from corrosive elements and improving coating properties also impart color to the coating composition and include such substances as inhibited aluminum leafing pigment dispersed in a hydrocarbon distillate such as mineral spirits, inhibited aluminum leafing pigment dispersed in a hydrophilic media such as isopropanol, and leafing mica dispersed in water. The preferred filler material is comprised of from about 78 to about 82% by weight inhibited aluminum leafing pigment dispersed in mineral spirits and is available from Siberline Manufacturing Co., Inc., Lincoln Drive, Tamaqua, Pa., under the product name Aquapaste 205-5. The most preferred filler material is comprised of from about 66 to about 70% by weight inhibited aluminum leafing pigment dispersed in isopropanol and is available from Siberline Manufacturing Co. under the product designation L-1959-PA.
The water soluble nonionic surfactant of the present inventive coating composition improves the wetting of the coating composition thereby helping filler material or pigment dispersion and inhibiting foam. These surfactants are also useful for reducing surface tension in the coating. Examples of suitable surfactants are acetylenic glycol, octylphenol ethoxylate, as well as many other surfactants which are well known in the coatings art. The preferred surfactant is a water soluble, liquid, nonionic octylphenol ethoxylate available from Union Carbide Chemicals and Plastics Company, Inc., Danbury, Ct. under the product name Triton® Nonionic Surfactant X-100. The most preferred surfactant is a water soluble nonionic acetylenic glycol available from Air Products and Chemicals, Inc., Performance Chemicals, 7201 Hamilton Boulevard, Allentown, Pennsylvania, under the product name Surfynol 465.
Those skilled in the art will recognize that the water used as the solvent in the present inventive coating composition is preferably distilled or deionized water.
The preferred coating composition of the present invention comprises (i) from 39.6 to 67.3% by weight of a phenylmethyl silicone resin emulsion having a total weight percent silicone resin solids content of approximately 48 to 72%; (ii) from 8.3 to 19.2% by weight of inhibited aluminum leafing pigment dispersed in either mineral spirits or isopropanol; (iii) from 0.05 to 3.0% by weight of water soluble nonionic acetylenic glycol; and (iv) from 10.5 to 52.0% by weight water, and has a total weight percent solids content of approximately 34.4 to 50.0 %.
The most preferred coating composition comprises (i) from 53.4 to 59.0% by weight of a phenylmethyl silicone resin emulsion having a total weight percent silicone resin solids content of approximately 58 to 62%; (ii) from 14.6 to 16.2% by weight of inhibited aluminum leafing pigment dispersed in either mineral spirits or isopropanol; (iii) from 0.3 to 0.5% by weight of water soluble nonionic acetylenic glycol; and (iv) from 24.3 to 31.7% by weight water, and has a total weight percent solids content of approximately 43.7 to 48.3%.
In addition to the above components, the present inventive coating composition may advantageously contain some or all of the following ingredients, including antifoams, pH buffers, anti-rust agents, biocides, fungicides, antifreeze agents, etc. However, some such additives may have an adverse effect on the coating's durability, corrosion resistance, coating properties and/or resistance to high temperatures.
In preparing the coating composition of the present invention, water and surfactant are blended together and the surfactant is allowed to dissolve for at least thirty (30) minutes. A filler material is then added to the resulting water solution. Dispersion of the filler material in the water solution is achieved by gentle agitation of the solution with a paddle to break apart the large agglomerates. This is followed by ensuring that the filler material is completely covered by the water solution and allowing the filler material to fully disperse by soaking for approximately 24 to 72 hours. During this period, the dispersion is agitated at least twice per day. A letdown is then prepared by blending a silicone resin emulsion and water for approximately 15 to 20 minutes. The letdown is allowed to fully dissolve for approximately 24 to 72 hours. The dispersion is then added to the letdown and thoroughly blended. The resulting admixture is then allowed to fully disperse for at least 24 hours. As can be well understood by those skilled in the art, excessive stirring during preparation of the coating composition of the present invention is to be avoided.
In addition to the above description, the coating compositions of the present invention are further developed by reference to the illustrative, but not limiting, examples set forth below.
SPECIFIC EMBODIMENT
In the working examples set forth below, the following components were used:
Emulsion--an anionic water emulsion of a soft phenylmethyl silicone resin obtained from Dow Corning® Corporation and having a product designation Dow Corning® 1-0468 resin emulsion.
Filler--a water dispersible, inhibited aluminum leafing pigment having a fine particle size obtained from Siberline Manufacturing Co. and having a product name Aquapaste 205-5.
Surfactant--a water soluble nonionic acetylenic glycol with inherent low foaming characteristics obtained from Air Products and Chemicals, Inc. and having a product name Surfynol 465.
Water--deionized water.
COATING COMPOSITION PREPARATION
The inventive coating composition was prepared according to the following method: 76.7 grams (g.) of Water and 2.2 g. of Surfactant were blended and the Surfactant allowed to dissolve for about 30 minutes to form a water solution. 76.7 g. of Filler was then added to the water solution and the resulting dispersion gently agitated with a spatula to break apart the large agglomerates. Care was taken to ensure that the Filler was completely covered by the water solution and then the Filler was allowed to fully disperse by allowing it to soak for 24 hours, minimum. During this period, the dispersion was agitated twice per day. 281.5 g. of Emulsion and 63 g. of Water were then blended together for about 15 to 20 minutes to form the letdown. The dispersion was then added to the letdown, thoroughly blended, and allowed to fully disperse for approximately 24 hours.
The inventive coating composition prepared by the above procedure had the following approximate physical properties:
Filler to Resin Solids ratio: 1.0 to 2.7
Percent Solids: 46.0
pH at 25° C.: 6.8
Density: 1.13 g/cm 3
Viscosity (ASTM D 4212; No. 1 Zahn Cup): 32 sec.
EXAMPLES 1 TO 6
The coating composition prepared by the above procedure was then applied to test panels. The test panels were aluminum alloy panels having the commercial designations Al Alloy 3003-0 and Al Alloy 6061-T6, and measuring either 0.032×2.0×4.0 inch or 0.125×4.0×4.0 inch. The test panels were conversion treated prior to coating by dipping or immersing each test panel into a no rinse chromate conversion coating consisting of a combination of hexavalent and/or trivalent chromium, mineral acids, and organic or inorganic binding agents and available from Betz Metchem, Inc., 200A Precision Drive, Horsham, Pa. under the product name Permatreat 1900; blowing off the excess coating with an air jet; and curing the coating 2 hours, minimum at 121±14° C. The inventive coating composition was then applied to the cured conversion coated test panels by dipping or immersing the panels in the coating composition; allowing the excess coating to drain from the panels; and curing the coating composition 45±10 minutes at 300°±25° F., and then 60±10 minutes at 350°±25° F., and then 90±10 minutes at 550°±25° F.
The test panels were then subjected to a variety of tests, the identity of which and the results obtained therefrom, as set forth below in Table I.
TABLE I__________________________________________________________________________SUMMARY OF EXAMPLES 1 TO 6 Al ALLOYEXAMPLE TEST PANEL PROPERTY TEST METHOD/DESCRIPTION RESULTS__________________________________________________________________________1 3003-0* Thickness Total thickness less substrate 0.0002 to 0.0004 inch thickness Hardness ASTM D 3363 Pencil hardness of F Adhesion ASTM D 3359, Test Method A except 5A, i.e., no peeling or parallel and 1/4 inch apart. (Ref. removal STD-141. Method 6301)2 3003-0* Fluid Appearance after exposure to Skydrol No wrinkling, roughening, Resistance 500B-4 and TT-S-735, Type III at blistering, checking or temperature for 168 hours crazing3 3003-0* Corrosion ASTM B 117, for 168 hours (Ref. No evidence of corrosion Resistance STD-810, Method 509)4 3003-0* Thermal Appearance, weight loss, and No evidence of flaking, Stability flexibility after exposure to air crazing, or cracking after 450° and 600° F. for 168 hours (Ref ASTM exposure and 90° bend D 522, Test Method A, for resistance weight loss = 5.7% (450° F.) cracking) weight loss = 17.2% (600° F.)5 3003-0* Heat and Appearance after exposure to air No evidence of cracking, Corrosion 500° F. for 72 hours followed by blistering, flaking, Resistance to salt spray, per ASTM B 117, for crazing, corrosion, or hours. deterioration6 6061-T6** Abrasion FED-STD-141, Method 6192, using Wear Index = 27 mg/100 Resistance gram load and CS-10 abrasive wheel. cycles__________________________________________________________________________ *Test panel measured 0.032 × 2.0 × 4.0 inch **Test panel measured 0.125 × 4.0 × 4.0 inch
The above-referenced Examples demonstrate that the coating composition of the present invention displays clearly acceptable properties for the intended application or uses thereof. In particular, the coating composition displays minimum thickness and viscosity so as to preclude core passage blockage of high temperature aluminum heat exchangers. Moreover, the composition displays abrasion resistance satisfactory to preclude sand and dust erosion and displays acceptable levels of heat and corrosion resistance.
Although this invention has been shown and described with respect to the specific embodiment thereof, it will be understood by those skilled in the art that various changes may be made without departing from the spirit and scope of the claimed invention. | Water based silicone coating compositions are provided that offer superior coating properties, durability and resistance to high temperatures and to the effects of corrosive environments. These coating compositions are especially useful for coating the external and intricate internal surfaces of high temperature aluminum heat exchangers. | 8 |
FIELD OF THE INVENTION
The present invention relates to rockets and more particularly to an autophage self-consuming rocket wherein the rocket casing becomes consumed during flight thereby decreasing the rocket weight.
BRIEF DESCRIPTION OF THE PRIOR ART
In order to minimize the effects of weight which limit the performance of a rocket, large air-breathing aircraft consist of complex mechanisms. One contemporary air-breathing aircraft of this type includes a first stage operating with: (1) a turbojet-propelled take-off mode, followed by (2) after burning acceleration to approximately Mach 3.0, and then (3) supersonic combustion ram jet propulsion to Mach 5.0-8.0 (using liquid hydrogen fuel), and finally (4) by fuse rocket into low Earth orbit. It is our contention that such an air-breathing rocket first stage is inordinately expensive and involves considerable reliability problems.
Better use can be made of the rather low specific impulse (I sp ) of available storable monopropellant liquid rocket fuels if one pays specific attention to the mass fraction of a launch vehicle system which may be considered as the ratio of total vehicle hardware weight as a fraction of total launch pad weight (including fuel).
The prior art has developed a concept of an autophage rocket which produces self consumption of the rocket casing during flight in an area of the casing corresponding to expended fuel.
The most relevant prior art is U.S. Pat. No. 3,127,739 issued to Miller on Apr. 7, 1964. This patent is directed to the physics of discarding inert weight as a rocket vehicle accelerates without dropping boosters. The patented device is directed to a solid propellant rocket which comprises a casing wall 20 having inner and outer wall members 22 and 24 filled with a solid propellant material 20 to ensure that the metal burns. The great disadvantage of the Miller device is the utilization of a double-walled container having wall members 22, 24 which adds greatly to the inert weight of the rocket. Accordingly the patented rocket design is of limited utility.
BRIEF DESCRIPTION OF THE PRESENT INVENTION
The present invention is an improvement over the prior art and of particular importance is the construction of a single-walled rocket casing from a material which is self consuming (does not require contact with a solid propellant) and still has the required structural strength. The preferred material of the present invention is non-metallic and therefore does not conduct heat nearly as fast as a metal casing which ensures that the burning surface will be only at the rocket exhausts, and not destructively forward of that point.
The present invention permits the utilization of the principle of ram-rocket (air-breathing when in air) and a secondary nozzle to expand the combustion products of the casing, as they are consumed, for additional impulse.
The present invention further includes a multiplicity of rocket motors which provide an inter-motor space for permitting the insertion of struts therebetween which are required to carry the secondary nozzle. The struts further provide a convenient place for mounting vanes which permits steering and stabilization of the vehicle. By individually controlling the multiplicity of rocket motors, an alternate form of controlled rocket movement may be effected.
BRIEF DESCRIPTION OF THE FIGURES
The above-mentioned objects and advantages of the present invention will be more clearly understood when considered in conjunction with the accompanying drawings, in which:
FIG. 1 is a diagrammatic cross-sectional view illustrating the basic internal components of an autophage rocket, in accordance with the present invention;
FIG. 2 is a bi-directional diagrammatic sectional view taken along a plane passing through section line 2--2 of FIG. 1;
FIG. 3 is a diagrammatic sectional view of an autophage rocket utilized as a booster for a manned space vehicle;
FIG. 4 is a detailed diagrammatic view of the aft end of the autophage rocket in accordance with the present invention;
FIG. 5 is a diagrammatic perspective view of the present invention utilizing skewed nozzles to achieve vehicle spin;
FIG. 6 is a plot of maximum vehicle velocity as a function of mass ratio;
FIG. 7 is a plot of maximum vehicle velocity as a function of effective exhaust velocity.
DETAILED DESCRIPTION OF THE INVENTION
It is a primary contention of the inventors that better use can be made of the rather low specific impulse (I sp ) of today's storable monopropellant rocket fuels, if specific attention is paid to the mass fraction of a launch vehicle system. The plots of FIGS. 6 and 7 illustrate the interrelationship between effective rocket exhaust velocity (which can be equated to I sp , the mass fraction or ratio (ε) of the total vehicle system metallic or "hardware" weight as a fraction of the total launch pad weight, and desired orbital velocity which, for example, may nominally be 25,000 ft./second referenced to zero Earth surface velocity. The plots demonstrate that, if it is possible to achieve a mass fraction of 95% (i.e., 95% fuel out of 100% launch pad weight), then one can achieve orbital velocity in a single-stage vehicle with a single propulsion system as opposed to a multiple propulsion system. This would be so even if the I sp is as low as 220 seconds which is typical of monopropellants. However, this is not possible without consuming a large part of the tank or casing weight during the ascent phase and having the consumption of this tank weight become a significant addition to the thrust of the system. In the prior art previously explored, the rocket casing is consumed but, due to the utilization of a metallic wall, objectionable dead weight must be overcome at the outset of flight.
FIG. 1 schematically illustrates a cross-sectional view of a rocket employing an improved autophage system. As the outer casing 12 of rocket 10 is "pulled down" over a nest of four rocket motors 24, 26 and 28, 30 (FIG. 2), the tubular casing 12 forming the rocket tank is consumed by the rocket motor exhausts. Thus, the amount of mass being accelerated by the rocket is continuously decreasing and at burnout the forward dome portion 16 of the casing will be positioned in overlying relation with the rear dome portion 18. Of course, the higher the fineness ratio of the tubular tank (length divided by diameter), more of the casing is consumed by the exhausts thereby increasing the final mass fraction.
A central tube 20 having a rack gear machined therein draws down dome portion 16 into confronting proximity with dome portion 18. The rate of this "draw down" depends upon the consumption of liquid fuel contained within the storage volume 14 of casing 12. In order to seal the propellant within casing 12, O-ring seals 19 and 21 each respectively form a fluid seal with the dome portion 18.
FIG. 4 illustrates in greater detail the components located in the aft end of the rocket. Outwardly of the exhaust end 31 of each motor is a space 35 where combustion of the tubular casing end occurs as the casing is "drawn down." As will be clearly shown in FIG. 4, gear teeth 23 are machined into the surface of the central tube 20 and are engaged by pin gear 22 which displaces central tube 20 from left to right, as viewed in FIG. 4. The sealing characteristics of the drive are increased by preferably having a plastic (polymer) coating over the central tube such that it can be drawn through seal 21 smoothly.
A high internal pressure in the monopropellant tank (typically 300 psi) is created without the use of gas pressure, and a controllable feed rate is established, such that the rate of consumption of the tubular portion of the tank exactly matches the rate at which that portion of the tank is being consumed at the rocket exhausts. Additional impulse for the rocket is gained by channelling the exhaust from the burned casing through an annular expansion nozzle 36 which is supported by four perpendicularly oriented struts 32, 34, 38 and 40 as shown in FIG. 2. Thus, the annular nozzle supported by the struts directs the thrust developed by consumption of fuel and casing into the main body of rocket 10. Attitude control vanes such as 42 and 44 may be connected to the aft edge of each strut in order to control the position of the rocket in flight.
By carefully considering FIGS. 2 and 4, it will be noted that the design of the present invention involves the ram-rocket principle when the vehicle is operated within the sensible atmosphere (up to 80,000 feet altitude) and, therefore, a ram inlet 58 is provided at the forward end of the circumferential expansion nozzle 36. The inclusion of a ram-rocket structure and an expansion nozzle to expand the products of casing combustion provides additional impulse which is highly desirable.
By utilizing a single propellant fuel system, disadvantages of bipropellant fuel systems are avoided since the latter unnecessarily complicates the number of tanks, feed pipes, and seals leading to a larger fixed (metallic) weight, thus reducing the mass fraction, although the I sp may be higher.
FIG. 3 illustrates a typical utilization of the present autophage rocket as a booster. As is indicated in the figure, a manned space vehicle generally indicated by reference numeral 46 is connected at its rearward portion to the forward dome portion 16 of rocket 10. Toward the burnout period of flight, the two dome portions 16 and 18 of rocket 10 will confront each other in overlying relation and at that point the rocket 10 may be separated from the space vehicle 46 at junction 48. It is to be emphasized that the invention resides in the rocket construction and not the utilization of the rocket with a manned space vehicle. Unlike the metallic casing and components utilized in prior art autophage rockets, the present invention preferably utilizes composite materials wherever possible. It is extremely important that casing 12 be fabricated from a relatively lightweight and strong material which is itself combustible. In a preferred embodiment of the invention, KEVLAR-epoxy is utilized since it contains about 30% resin, which is quite combustible. A further advantage of this KEVLAR-epoxy material is that it does not conduct heat nearly as fast as metals do, so that the burning surface will be at the rocket exhausts, and not destructively forward of that point. The utilization of KEVLAR-epoxy in rocketry has been explored by the Hercule's Powder Company, which has employed the material as a solid rocket case for the Space Shuttle Solid Rocket Booster. However, the present invention is the first known attempt to employ such a casing as a combustible, expendable rocket housing in accordance with the autophage principle.
An important consideration in the selection of casing material is to choose a material which has an intrinsic heat of combustion, which in combination with the proper monopropellant mixture ratio will actually add the casing's heat of reaction to the total energy of the system. If KEVLAR is employed as the casing material, it is preferable to dissolve ammonium perchlorate (NH 4 ClO 4 ) in an ethylene oxide monopropellant (C 2 H 4 O). Then there could be sufficient excess oxygen to "burn" the outer casing even outside the atmosphere. Hydrazine is an alternate acceptable fuel. While in the presence of the atmosphere, the aerodynamic expansion nozzle 36 forming a shroud around the four rocket motors 24, 26, 28 and 30 will provide sufficient oxygen to "burn" the outer casing 12, expand its exhaust products, and produce additional thrust, as in a ram-rocket.
Accordingly, in addition to the propellant, there are three additional sources of thrust which can reduce the mass fraction sensitivity of an autophage rocket. They are: (1) the addition of a miscible oxidizer in the monopropellant fuel so as to raise the fuel's I sp ; (2) the heat of combustion of the outer casing composite material can be augmented by including a small percentage of oxidizer in its epoxy binders; and (3) the additional impulse (I sp ) which can be obtained from the sensible oxygen in the atmosphere (up to 80,000 feet) as the rocket rises from sea level to that altitude by relying upon the aerodynamic expansion nozzle 36 and the ram-rocket principle.
Because the present rocket structure is consumable after each flight, the parts must be fabricated at the least possible cost. For this reason, cryogenic propellants have not been considered, nor have storable bipropellants been considered. Rather, enriched storable monopropellants have been selected. The present design also avoids the expense of turbopumps and gas pressurization systems. A simple drive, such as the discussed rack and pinion "pull-down" drive forces the monopropellant into respective rocket engine exhausts in a satisfactory manner. In addition, the present design may avoid expensive gimbaled rocket nozzles. The present invention permits the utilization of simple vanes such as 42 and 44 (FIG. 4) in relatively cool monopropellant exhaust streams. By virtue of the present design, it is possible to exclude regenerative cooling of rocket components since high performance composites such as carbon-carbon composite may be employed.
Considering the rocket motors in detail (as shown in FIG. 4), each of the motors 24, 26, 28 and 30 includes a number of monopropellant spray nozzles 50, 54 and 56 which are preferably in the nature of burst diaphragm closures that inject monopropellant into the rocket motors. Catalyst beds such as 27 and 29 are located in each of the rocket motors and they are typically platinum coated for maximizing combustion efficiency for monopropellant fuel.
Since the present invention is a zero pressure storage system, it can be kept in space without danger of leakage for as long as the life of the batteries permit.
In continued consideration of FIG. 4, the control vanes such as 42 and 44, respectively connected to struts 32 and 34, may be removed in favor of installing a conventional micro-metering valve, such as 52, on each of the monopropellant spray nozzles 50, 54 and 56 because with a spinning missile the timing of side force application with spin rate is very critical. Controlling propellant injection is far less wasteful of chemical energy than the few degrees of lateral control which can be achieved with the control vanes. An additional design consideration may be the inclusion of a side exhaust port (not shown) adjacent to each of the motors 24, 26, 28 and 30 to obtain more lateral reaction forces on the vehicle than is possible with unequal flow through the expansion nozzle 36.
In the alternate embodiment shown in FIG. 5, a separate dome 74 is installed within the casing of the illustrated rocket 60. The embodiment of FIG. 5 differs from that of FIG. 4 in that four skewed nozzles 62, 64, 68 and 70 are employed to spin the vehicle which enhances thrust vector control. The dome 74 is drawn down toward dome 72 by an illustrated conductor wire mounted on motor driven winch 86 within nose section 76. Thus, the means for drawing down the domes toward one another, as fuel is consumed, may take a number of forms. The winch motor 82 is powered by batteries 84, all of which are enclosed within the fore portion 80 of nose section 76.
When the rocket is to operate outside the atmosphere, the ram-rocket inlet 58 (FIG. 4) is closed as indicated by dotted lines over the lower inlet, in which case the outer casing 12 would continue to neatly slide into the exhausts of the four rocket motors when combustion of the casing occurs prior to final expansion through nozzle 36.
The preferable use of composite materials may be extended to other rocket parts. The central draw down tube 20 is preferably fabricated from a boron composite material with rack teeth machined into it and the aerodynamically shaped expansion nozzle 36 would preferably be fabricated from a carbon-carbon composite material.
It should be understood that the invention is not limited to the exact details of construction shown and described herein for obvious modifications will occur to persons skilled in the art. | An autophage rocket has its casing constructed from KEVLAR-epoxy material which is itself combustible and stores liquid propellant. As the propellant is consumed during flight, the casing is combusted so that the pressure within the casing remains constant. A secondary nozzle is mounted to the outlet end of the rocket and cooperates with a ram-rocket construction to achieve additional impulse. A multiplicity of rocket motors are fed from a single stage tank to enable controlled motion of the rocket. | 5 |
This is a division, of application Ser. No. 656,909 filed Feb. 10, 1976, now U.S. Pat. No. 4,173,567.
FIELD OF THE INVENTION
This invention relates to new organic isocyanates, to a process for their production and to their use as reactants for compounds containing isocyanate-reactive hydrogen atoms.
BACKGROUND OF THE INVENTION
German Offenlegungsschrift No. 2,329,300 relates to heterocyclic polyisocyanates obtained by reacting diisocyanates with hydrocyanic acid. In addition to hydrocyanic acid, compounds which eliminate hydrocyanic acid, such as, for example, the addition products of hydrocyanic acid with aldehydes or ketones (cyanhydrins), are also recommended as starting materials. The structure of the polyisocyanates obtained by the process according to DT-OS No. 2,329,300 is independent of whether hydrocyanic acid or the above-mentioned hydrocyanic acid derivatives are used as starting material (Example 10 of DT-OS No. 2,329,300). This discovery can be attributed to the fact that the authors of DT-OS No. 2,329,300 used reaction conditions under which the hydrocyanic acid adducts with aldehydes or ketones decomposed into their constituents, hydrocyanic acid and aldehyde or ketone, before reaction with the diisocyanate.
It has now surprisingly been found that new isocyanates having advantageous properties by comparison with the isocyanates of the above-mentioned prior art can be obtained by carrying out the reaction between diisocyanate and cyanhydrins in a first reaction stage under such mild conditions that the cyanhydrin is not decomposed into hydrocyanic acid and carbonyl compound, but instead a simple adduct of the cyanhydrin with the diisocyanate is initially formed. The action of heat on this intermediate product in the presence of excess quantities of starting diisocyanate results in the formation of new heterocyclic isocyanates corresponding to general formula (I) below (n=O, Y=--O--). These new isocyanates are distinguished from the isocyanates according to DT-OS No. 2,329,300 obtained from the corresponding starting materials in particular by their much lower viscosity and by the better lacquer properties of the polyurethane lacquers produced from them.
According to the invention it has also been found that isocyanates which are largely similar in structure and properties, and which, in particular, have valuable lacquer properties, are formed from organic diisocyanates by a similar reaction with α-aminonitriles, β-hydroxy or β-aminonitriles.
SUMMARY OF THE INVENTION
Accordingly, the present invention relates to new isocyanates corresponding to the formula: ##STR1##
The invention also relates to a process for the production of the compounds of formula (I) wherein an organic diisocyanate corresponding to the formula:
OCN--R--NCO (II)
is reacted with a compound corresponding to the formula: ##STR2## to form an adduct corresponding to the formula: ##STR3## and the adduct thus formed is subsequently converted into the required end product (I) by the heating in the presence of excess quantities of the diisocyanate of formula (II).
The invention also relates to the use of the preferred polyisocyanates described in more detail below, obtainable by the process according to the invention, as reactants for compounds containing at least two isocyanate-reactive hydrogen atoms in the production of polyurethane plastics by the isocyanate polyaddition process known per se.
In the above formulae and hereinafter, R, R 1 , R 2 , X, Y, Z and n have the following meanings:
R represents an aliphatic hydrocarbon radical having 2 to 12 carbon atoms, a cycloaliphatic hydrocarbon radical having 4 to 15 carbon atoms, an aromatic hydrocarbon radical having 6 to 15 carbon atoms or an araliphatic hydrocarbon radical having 7 to 15 carbon atoms optionally substituted by halogen, C 1 -C 4 -alkyl, methoxy, nitro, and/or C 1 -C 4 -carbalkoxy groups. R preferably represents an aliphatic hydrocarbon radical having 4 to 8 carbon atoms or a cycloaliphatic hydrocarbon radical having 5 to 10 carbon atoms.
R 1 and R 2 are the same or different and represent hydrogen an aliphatic hydrocarbon radical having 1 to 17 carbon atoms, a cycloaliphatic hydrocarbon radical having 4 to 15 carbon atoms, an aromatic hydrocarbon radical having 6 to 15 carbon atoms or an araliphatic hydrocarbon radical having 7 to 15 carbon atoms optionally substituted by halogen, C 1 -C 4 -alkyl, methoxy, nitro or C 1 -C 4 -carbalkoxy groups, or together with the ring carbon atom form a cycloaliphatic ring having 4 to 8 carbon atoms. R 1 and R 2 preferably represent an optionally olefinically unsaturated aliphatic hydrocarbon radical having 1 to 4 carbon atoms or, together with the ring carbon atom, a cycloaliphatic hydrocarbon radical having 5 to 6 carbon atoms.
X represents hydrogen or --CO--NH--R--NCO. X preferably represents --CO--NH--R--NCO.
Y represents --O-- or --N(R 3 )--, where R 3 is hydrogen, an aliphatic hydrocarbon radical having 1 to 4 carbon atoms, a cycloaliphatic hydrocarbon radical having 5 to 6 carbon atoms, a phenyl radical or --CO--NH--R--NCO. Y preferably represents --O--.
Z represents --O-- or a radical --N(R 4 )--, where R 4 is hydrogen, an aliphatic hydrocarbon radical having 1 to 4 carbon atoms or a cycloaliphatic hydrocarbon radical having 5 to 6 carbon atoms or a phenyl radical. Z preferably represents --O--.
n=0 or 1, preferably 0.
DETAILED DESCRIPTION OF THE INVENTION
In the process according to the invention, diisocyanates of formula (II) are reacted with hydroxy or aminonitriles of formula (III) at a temperature in the range from about -25° C. to +200° C. and preferably at a temperature in the range from about 0° C. to 180° C., preferably in the presence of suitable catalysts. The process according to the invention may be carried out, for example, by initially introducing the reactants in admixture and initiating the reaction by adding the catalyst. However, it may also be carried out by initially introducing the diisocyanate and catalyst, followed by addition of the hydroxy or aminonitrile. The process according to the invention probably passes through an intermediate stage of formula (IV) which is cyclized at elevated temperature into compounds of formula (I) (X=H, Y=--O-- or --N(R 4 )--). If desired the diisocyanates or triisocyanates (I) according to the invention, in which X represents --CO--NH--R--NCO and Y represents --O-- or --N(R 3 )-- (R 3 =--CO--NH--R--NCO), are then formed by a secondary reaction with excess diisocyanate (II) with the group ═NX with the group --NR 4 -- (R 4 =H). Especially in cases where the α-hydroxy nitriles, which represent particularly preferred starting compounds (III) for the process according to the invention, are used, it is important to ensure, by careful temperature treatment at the beginning of the reaction, that the addition reaction between (II) and (III) takes place before the hydroxy nitrile (III) decomposes into its constituents HCN and ##STR4## In practice, this result is achieved by carrying out the primary reaction between (II) and (III) to form the intermediate product (IV) at a temperature in the range from about -25° C. to +80° C. and preferably at a temperature in the range from about +15° C. to +25° C. It is advisable to carry out the first step of the reaction at the same temperature in those cases where α-aminonitriles are used as starting materials. The temperature of the first reaction step is, however, less critical in the case where β-hydroxynitriles or β-aminonitriles are used as starting materials. In these cases the first reaction step can be carried out within above wide range from about -25° C. to +200° C. preferably from about 0° C. to 180° C. In order subsequently to cyclize the intermediate product (IV), the reaction mixture is then heated to elevated temperatures this means to about 40° to 160° C. preferably 60° to 120° C.
In general, from about 5 to 15 mols of diisocyanate (II) are preferably used per mol of compound (III) in the process according to the invention. The primary reaction between (III) and (II) to form (IV) is over when the heat effect observed when the reactants are combined with the catalyst abates. The end of the cyclization reaction is indicated by the disappearance of the nitrile edge in the infra red spectrum.
If desired, unreacted diisocyanate may be removed on completion of the reaction, for example, by thin-layer or rotary distillation or by extraction with solvents, for example, cyclohexane, hexane or petroleum ether. However, the solutions of the new polyisocyanates in the diisocyanates used as starting compounds, obtainable in the process according to the invention, are also suitable for numerous applications which are mentioned in more detail hereinafter. As already mentioned, the formation of diisocyanates corresponding to the above general formula may be controlled by varying temperature. The formation of triisocyanates is possible not only in cases where Y=--NH, but may also be obtained in cases where Y=--O-- by a secondary reaction, i.e. by reacting the excess diisocyanate used as starting material with the diisocyanate according to the invention (reaction of the diisocyanate with the group --CO--NH--R--). In addition, heating the reaction mixture to elevated temperatures for several hours results in the formation of mixtures which, in addition to diisocyanates and triisocyanates, contain homologues of higher molecular weight. At elevated temperatures, polyisocyanates containing uretdione, biuret or isocyanurate groups can also be expected to be formed in addition to the homologues of higher molecular weight. In the formation of these secondary products is undesirable, it is advisable to carry out the process according to the invention at low temperatures in the range from about 0° C. to 80° C., in which case the reaction mixture is heated to this temperature for about 30 to 120 minutes. monoisocyanates are formed if the reaction temperature is kept below 80° C. Above secondary reaction leading to di- and triisocyanates take place at temperatures of above 80° C. as e.g. 80°-200° C. The degree of diisocyanate and/or triisocyanate formation by said secondary reactions can be determined by controlling the NCO-content of the reaction mixture.
Providing these precautionary measures are taken, removal of the excess starting diisocyanate leaves and products of which at least about 70% and preferably at least about 90% consist of the mono-, di- and tri-isocyanates corresponding to general formula (I) above.
The catalysts used, which are mentioned hereinafter, may generally remain in the reaction products without any adverse effect upon the stability of the end products in storage. In cases where the catalysts used in accordance with the invention are harmful in the production of plant protection agents, PU-plastics, PU-lacquers and PU-films, they are removed by filtration, centrifuging or decanting (insoluble catalysts) or are deactivated by alkylation, acylation or salt formation.
Any organic diisocyanates corresponding to the general formula R(NCO) 2 , where R is as defined above, may be used in the process according to the invention. Preferred aliphatic or cycloaliphatic diisocyanates are, for example, tetramethylene diisocyanate, pentamethylene diisocyanate, hexamethylene diisocyanate, 1,3-cyclopentylene diisocyanate, 1,4-cyclohexylene diisocyanate, 1,2-cyclohexylene diisocyanate, hexahydroxylylene diisocyanate, 4,4'-dicyclohexyl diisocyanate, 1,2-di-(isocyanatomethyl)-cyclobutane, 1,3-bis-(isocyanatopropyl)-2-methyl-2-propyl propane, 1-methyl-2,4-diisocyanatocyclohexane, 1-methyl-2, 6-diisocyanatocyclohexane, bis-(4-isocyanatocyclohexyl)-methane, 1,4-diisocyanatocyclohexane and 1,3-diisocyanatocyclohexane or 3,3,5-trimethyl-5-isocyanatomethyl cyclohexyl isocyanate ("isophorone diisocyanate"). In addition to aliphatic and cycloaliphatic diisocyanates of this kind, it is also possible in the process according to the invention to use aromatic diisocyanates such as, for example, 2,4-diisocyanatotoluene, 2,6-diisocyanatotoluene or 4,4'-diisocyanatodiphenyl methane, araliphatic diisocyanates, such as m- or p-xylylene diisocyanate, or diisocyanates containing ester groups such as 2,6-diisocyanato caproic acid esters, β-isocyanatoethyl esters and γ-isocyanatopropyl esters of isocyanato caproic acid.
Hydroxy and aminonitriles (III) suitable for use in the process according to the invention are the following:
(1) α-hydroxy nitriles such as, for example, the cyanhydrins of formaldehyde, acetaldehyde, propionaldehyde, butyraldehyde, isobutyraldehyde, acetone, methylethyl ketone, isopropyl methyl ketone, monochloracetone, benzaldehyde, o-nitrobenzaldehyde, m-nitrobenzaldehyde, p-nitrobenzaldehyde, o-chlorobenzaldehyde, m-chlorobenzaldehyde, p-chlorobenzaldehyde, o-methoxy benzaldehyde, p-methoxy benzaldehyde, m-methyl benzaldehyde, p-methyl benzaldehyde, benzyl methyl ketone, β-phenyl ethyl ketone, β-phenyl propyl ketone, cyclopentanone, cyclohexanone, isopropyl phenyl ketone, cyclohexyl phenyl ketone, 2-methyl cyclohexanone, 3-methyl cyclohexanone, 4-methyl cyclohexanone, cycloheptanone, chloral, acrolein, crotonaldehyde and acetoacetic acid ethyl ester.
(2) α-aminonitriles such as, for example, α-aminoacetonitrile, α-aminopropionitrile, α-amino-α-methyl propionitrile, α-(N-methyl amino)-propionitrile, α-aminobutyronitrile, α-aminoisobutyronitrile, α-amino-α-methyl propionic acid nitrile, α-amino-α-methyl isobutyronitrile, α-methyl aminoisobutyronitrile, α-butyl aminoisobutyronitrile, α-cyclohexyl aminoisobutyronitrile, α-phenyl aminoisobutyronitrile, α-1-cyclohexyl amino-1-cyanocyclohexane and (α-amino-α-phenyl acetic acid nitrile).
(3) β-hydroxy nitriles such as, for example, β-hydroxy propionitrile, β-hydroxy-α-methyl propionitrile, β-hydroxy-β-methyl propionitrile, β-hydroxy-β-cyclohexyl propionitrile and β-hydroxy-β-phenyl propionitrile.
(4) β-aminonitriles such as, for example, β-aminopropionitrile, β-methyl aminopropionitrile, β-hexyl aminopropionitrile, β-cyclohexyl aminopropionitrile, β-amino-α-methyl propionitrile and β-methyl amino-β-methyl propionitrile.
It is, of course, also possible in the process according to the invention to use any mixtures of the compounds (III) mentioned by way of example in (1) to (4) above, more especially for controlling the service properties of the end products. The cyanhydrins of the unsubstituted aliphatic or cycloaliphatic aldehydes or ketones mentioned in (1) above are particularly preferred for the process according to the invention.
Compounds accelerating the isocyanate polyaddition reaction, known per se from polyurethane chemistry, are used as catalysts in the process according to the invention. Compounds of this kind are, in particular, tertiary amines such as, for example, triethyl amine, diaza-bicyclo-(2,2,2)-octane, 1,5-diaza-bicyclo-(4,3,0)-non-5-ene, 1,8-diaza-bicyclo-(5,4,0)-undec-7-ene, dimethyl aniline, dimethyl benzyl amine, pyridine, 2-, 3-, 4-picoline, N,N-diethyl aniline, quinoline, N-methyl piperidine, N-methyl dicyclohexyl amine, N,N-dimethyl cyclohexyl amine, N-cyclohexyl piperidine, N-cyclohexyl morpholine and 2,6-, 2,4-lutidine; organic zinc compounds, such as, for example, those of 2-ethyl caproic acid, organic tin compounds such as, for example, dibutyl tin dilaurate, bis-(tributyl tin)-oxide, dibutyl tin-bis-(2-ethyl hexoate) or tetrabutyl tin. Other suitable catalysts are lead compounds, such as, trimethyl lead acetate or N-(tri-n-butyl lead)-imidazole or phosphorus compounds, such as, triphenyl phosphine or tributyl phosphine, and basic salts of hydrocyanic acid, such as sodium cyanide or potassium cyanide. The catalysts mentioned by way of example are used in quantities of from about 0.01 to 3 mol % and preferably in quantities of from about 0.05 to 1 mol %, based on compound (III), in the process according to the invention. Further suitable catalysts are disclosed in Polyurethanes: Chemistry and Technology, Part I, by Saunders and Frisch, Interscience Publishers, 1964.
The process according to the invention may be carried out either in the absence or even in the presence of an inert organic solvent. Suitable inert solvents are, for example, aliphatic and cycloaliphatic hydrocarbons, halogencontaining hydrocarbons such as methylene chloride, chloroform, di- and tri-chlorethylene, aromatic hydrocarbons, such as benzene, toluene, xylene, halogenated aromatic hydrocarbons such as chlorobenzene, dichlorobenzene, and trichlorobenzene, dioxane, ethyl acetate, ethyl glycol acetate, acetone, acetonitrile, dimethyl formamide and mixtures of these solvents.
The polyisocyanates (I) according to the invention represent a new class of organic polyisocyanates. The fact that they are compounds having the general structure indicated above is apparent from molecular weight determination and from infrared (Makromol. Chem. 78, 191 (1964), nuclear resonance and mass spectroscopic data. The new compounds are suitable for use as intermediate products in the production of plant-protection agents and in particular represent valuable starting materials for the production of polyurethane plastics. In particular, the polyisocyanates according to the invention having aliphatically bound isocyanate groups are valuable starting materials for the production of light-stable polyurethane lacquers and films. The new polyisocyanates are readily soluble in conventional lacquer solvents and are highly compatible with pigments. They are particularly suitable for low-solvent lacquer systems owing to their low viscosity. Their greatly reduced vapor pressure by comparison with the corresponding diisocyanates used as starting materials, and their resulting physiological acceptability, are of considerable practical significance.
EXAMPLE 1
2016 g of hexamethylene diisocyanate (12 mols) and 1 ml of triethyl amine are initially introduced into a three-necked flask, followed by the dropwise addition over a period of 30 minutes at room temperature of 68.4 g of glycol nitrile (1.2 mols). The mixture is then slowly heated to 160° C. and, after 10 minutes at that temperature, is cooled to room temperature. The catalyst is destroyed by means of benzoyl chloride and the reaction product freed from excess hexamethyl diisocyanate by thin-layer distillation.
Yield: 530 g of a diisocyanate having the following idealized structure: ##STR5##
NCO found: 21.3%
NCO calculated: 21.4%
η 25 ° C.: 440 cP
Analysis: calculated: C 54.95, H 6.92, N 17.80, O 20.33. found: C 55.1, H 7.00, N 18.1, O 20.3.
EXAMPLE 2
2523 g of hexamethylene diisocyanate (15 mols) are reacted with 157 g of isobutyraldehyde cyanhydrin (1.5 mols) in the presence of 2 g of diaza-bicyclo-(2,2,2)-octane in the same way as in Example 1. Removal of the excess hexamethylene diisocyanate by extraction with cyclohexane leaves 772 g of a diisocyanate having the following idealized structure: ##STR6##
η 25 ° C.: 2080 cP
NCO calculated: 19.3%
NCO found: 19.1%
Analysis: calculated: C 57.91, H 7.64, N 16.08, O 18.37. found: C 57.8, H 7.7, N 16.3, O 13.3.
EXAMPLE 3
53 g (0.5 mol) of benzaldehyde (freshly distilled) and 0.5 ml of triethylamine are combined in a stirrer-equipped vessel and 20 ml of hydrocyanic acid (0.5 mol) added dropwise at such a rate that the temperature does not exceed 40° C. After stirring for 60 minutes at room temperature, 841 g of hexamethylene diisocyanate (5 mols) and 0.5 ml of the zinc(II)salt of 2-ethyl caproic acid are added. The further procedure is then as described in Example 1.
Removal of the monomer leaves 180 g of a diisocyanate having the following idealized structure: ##STR7##
η 25 ° C.: 1050 cP
NCO found: 17.5%
NCO calculated: 17.92%
Analysis: calculated: C 61.39, H 6.66, N 14.92, O 17.04. found: C 60.9, H 6.5, N 14.9, O 17.0.
EXAMPLE 4
841 g of hexamethylene diisocyanate (5 mols) are reacted with 41.5 g of acrolein cyanhydrin (0.5 mol) in the presence of 0.5 ml of quinoline and 1 g of pyrocatechol in the same way as in Example 1. The reaction mixture obtained is subject to thin-layer distillation twice at 180° C. in an oil pump vacuum.
Yield: 190 g of a diisocyanate having the following idealized structure: ##STR8##
η 25 ° C.: 715 cP
NCO calculated: 20.0%
NCO found: 19.9%
Analysis: calculated: C 57.26, H 6.97, N 16.70, O 19.07. found: C 57.2, H 7.2, N 16.7, O 19.3.
EXAMPLE 5
3360 g of hexamethylene diisocyanate (20 mols), 186.9 g of cyclohexanone cyanhydrin (1.5 mols), 1 ml of tin octoate and 1 ml of triethyl amine, are reacted as described in Example 1. Removal of the monomer leaves 782 g of a polyisocyanate having the following idealized structure: ##STR9##
η 25 ° C.: 1770 cP
NCO calculated: 18.2%
NCO found: 17.9%
Analysis: calculated: C 59.85, H 7.64, N 15.17, O 17.33. found: C 59.8, H 7.8, N 15.4, O 17.3.
EXAMPLE 6
3364 g of hexamethylene diisocyanate (20 mols) and 2 mols of acetaldehyde cyanhydrin (142 g) are mixed under nitrogen in a 5 liter capacity stirrer-equipped apparatus. Following the addition of 1 ml of zinc octoate, a weakly exothermic reaction begins, being over after 30 minutes. Following the addition of 1 ml of triethyl amine, the mixture is stirred for 15 minutes at room temperature, quickly heated to 160° C. and kept at that temperature for 15 minutes. The reaction mixture is freed from excess hexamethylene diisocyanate by thin-layer distillation.
Yield: 952 g of a polyisocyanate having the following idealized structure: ##STR10##
η 25 ° C.: 480 cP
NCO calculated: 20.6%
NCO found: 20.3%
Analysis: calculated: C 56.0, H 7.17, N 17.09, O 19.63. found: C 55.8, H 7.3, N 17.0, O 20.0.
EXAMPLE 7
2523 g of hexamethylene diisocyanate (15 mols) and 127 g of propionaldehyde cyanhydrin are reacted in the presence of 1 ml of zinc octoate and 1 ml of triethylamine in the same way as described in Example 6.
Yield: 821 g of polyisocyanate having the following idealized structure: ##STR11##
η 25 ° C.: 720 cP
NCO calculated: 19.95%
NCO found: 19.7%
Analysis: calculated: C 56.99, H 7.41, N 16.62, O 18.98. found: C 56.7, H 7.2, N 16.8, O 19.0.
EXAMPLE 8
841 g of hexamethylene diisocyanate (5 mols) are mixed at room temperature with 78.5 g of acetoacetic ester cyanhydrin (0.5 mol), 0.5 ml of zinc octoate and 0.5 ml of triethylamine in a stirrer-equipped vessel. The mixture is then heated for 10 minutes to 160° C. and the catalyst neutralized with 0.5 ml of acetyl chloride. The reaction product is subjected to thin-layer distillation twice at 180° C. in an oil pump vacuum and all but 0.1% of the monomer, (hexamethylene diisocyanate), removed.
Yield: 195 g of a polyisocyanate having the following idealized structure: ##STR12##
η 25 ° C.: 5200 cP
NCO calculated: 17.05%
NCO found: 16.8%
Analysis: calculated: C 55.97, H 7.15, N 14.19, O 22.69. found: C 55.7, H 6.93, N 14.5, O 22.8.
EXAMPLE 9
42.5 g of acetone cyanhydrin (0.5 mol) and 0.5 g of diazabicyclo-(2,2,2)-octane are added to 1250 g of 4,4'-di-isocyanatodiphenyl methane (5 mols), followed by heating for 60 minutes to 160° C. After 30 minutes at that temperature, the reaction mixture is left to cool. 1240 g of a polyisocyanate having the following idealized structure: ##STR13## in 3 mols of 4,4'-diisocyanatodiphenyl methane are obtained. The monomer-free polyisocyanate may be freed from the monomer by extraction.
NCO calculated: 14.86%
NCO found: 14.5%
Analysis: calculated: C 69.73, H 4.65, N 11.96, O 13.66. found: C 69.5, H 4.4, N 12.1, O 13.8.
EXAMPLE 10
870 g of 2,4-diisocyanatotoluene (5 mols) are combined while stirring in a reaction vessel with 0.5 g of 1,5-diazabicyclo-(4,3,0)-non-5-ene, 0.5 g of dibutyl tin dilaurate and 42.5 g of acetone cyanhydrin (0.5 mol), followed by heating for 2 hours to 150° C. After another 30 minutes, the reaction mixture is left to cool and, providing the reaction mixture is not directly used for further reactions, is extracted with cyclohexane until the monomer has been removed. 285 g of a polyisocyanate having the following idealized structure: ##STR14## in the form of a white solid melting at approximately 195° C. are obtained.
NCO calculated: 19.4%
NCO found: 19.1%
Analysis: calculated: C 60.96, H 4.42, N 16.16, O 18.46. found: C 60.7, H 4.6, N 16.3, O 18.2.
EXAMPLE 11
841 g of hexamethylene diisocyanate (5 mols), 50 g of methyl ethyl ketone cyanhydrin, 0.5 g of triethylamine and 0.5 ml of zinc octoate are reacted in the same way as described in Example 1. On cooling, the triethylamine is blocked by the addition of 0.6 g of p-toluene sulphonic acid chloride.
The mixture is introduced cold into the thin-layer distillation apparatus in which it is subjected to thin-layer distillation at 180° to 185° C./0.05 Torr (oil pump).
Yield: 218 g of a polyisocyanate having the following idealized structure: ##STR15##
η 25 ° C.: 3200 cP
NCO calculated: 19.3%
NCO found: 19.5%
Analysis: calculated: C 57.91, H 7.64, N 16.08, O 18.34. found: C 58.2, H 7.81, N 15.9, O 18.1.
EXAMPLE 12
In a stirrer-equipped apparatus, 20 ml of hydrocyanic acid (0.5 mol) are added to 85 g (0.5 mol) of undecanone-(2) in the presence of 0.5 ml of triethylamine, followed by stirring for 30 minutes at 40° C. 841 g of hexamethylene diisocyanate (5 mols) and 0.5 ml of tin octoate are introduced into the cooled mixture. After heating for 60 minutes to 160° C., the mixture is stirred for 30 minutes at that temperature. After cooling, a polyisocyanate having the following idealized structure can be isolated by thin layer distillation in a yield of 293 g: ##STR16##
η 25 ° C.: 3650 cP
NCO calculated: 15.75%
NCO found: 16.1%
Analysis: calculated: C 63.01, H 8.88, N 13.12, O 14.99. found: C 63.2, H 8.91, N 13.1, O 14.7.
EXAMPLE 13
Following the procedure described in Example 1, 3364 g of hexamethylene diisocyanate (20 mols) and 170 g of acetone cyanhydrin (2 mols) are mixed with catalytic quantities of zinc octoate and triethylamine and, after the exothermic reaction has abated, the reaction mixture is heated to 160° C. and kept at that temperature for 10 minutes. The cooled reaction mixture can be obtained free from monomer by countercurrent extraction in a column with cyclohexane or petroleum ether.
Yield: 1042 g of a polyisocyanate having the following idealized structure: ##STR17##
η 25 ° C.: 1720 cP
NCO calculated: 19.9%
NCO found: 19.6%
Analysis: calculated: C 56.99, H 7.41, N 16.62, O 18.98. found: C 57.1, H 7.12, N 16.9, O 18.7.
EXAMPLE 14
Following the procedure of Example 1, 222 g of isophorone diisocyanate (1 mol), 8.5 g of acetone cyanhydrin (0.1 mol), 0.1 mol of zinc octoate and 0.1 ml of triethylamine are heated for 1 hour to 160° C. and subsequently subjected to thin-layer distillation at 180° C./0.2 Torr. 47 g of a resin-like polyisocyanate having the following idealized structure are obtained: ##STR18##
NCO calculated: 15.9%
NCO found: 15.7%
Analysis: calculated: C 63.49, H 8.18, N 13.22, O 15.10. found: C 63.2, H 8.0, N 13.4, O 15.3.
EXAMPLE 15
673 g of hexamethylene diisocyanate (4 mols) and 174 g of 2,4-diisocyanatotoluene (1 mol) are reacted with 42.5 g of acetone cyanhydrin (0.5 mol) in the presence of 0.5 ml of triethylamine. After the weakly exothermic reaction has abated, the reaction mixture is heated for 1 hour to 160° C. A clear, low-viscosity reaction product is obtained after cooling and may be freed from the monomer by extraction with ether. The monomer-free polyisocyanate has the following idealized structure: ##STR19##
NCO calculated: 19.65%
NCO found: 19.3%
Analysis: calculated: C 59.0, H 5.90, N 16.39, O 18.72. found: C 58.8, H 5.81, N 16.40, O 18.8.
EXAMPLE 16
841 g of hexamethylene diisocyanate (5 mols) are reacted with 42.5 g of acetone cyanhydrin (0.5 mol) in the presence of 0.2 ml of triethylamine and 0.2 ml of zinc octoate by stirring the reaction mixture for 3 hours at 70° C. The unreacted hexamethylene diisocyanate is then removed from the reaction product by extraction with petroleum ether. 130 g of a reaction product essentially consisting of a monoisocyanate having the following idealized structure are obtained: ##STR20##
NCO calculated: 16.6%
NCO found: 16.9%
Analysis: calculated: C 56.90, H 7.56, N 16.59, O 18.95. found: C 57.0, H 7.71, N 16.3, O 18.8.
EXAMPLE 17
In a stirrer-equipped apparatus, 336 g of hexamethylene diisocyanate (2 mols) are reacted for 2 hours at 40° C. with 21.3 g of acetaldehyde cyanhydrin (0.3 mol). 0.1 g of diaza-bicyclo-(2,2,2)-octane and 0.01 g of tin octoate are used as catalyst. The reaction product is obtained free from monomer by extraction with cyclohexane/petroleum ether. 75 g of a reaction product essentially consisting of a monoisocyanate having the following idealized structure are obtained: ##STR21##
NCO calculated: 17.6%
NCO found: 17.9%
Analysis: calculated: C 55.21, H 7.16, N 17.56, O 20.06. found: C 55.30, H 7.42, N 17.3, O 19.7.
EXAMPLE 18
To prepare a lacquer, 154 parts by weight of a polyester, prepared from phthalic acid anhydride and trimethylol propane, OH-number 260, in the form of a 65% solution in ethyl glycol acetate, 8.40 parts by weight of zinc octoate (8% of Zn) in the form of a 10% solution in xylene, 105.30 parts by weight of titanium dioxide and 141.80 parts by weight of ethyl glycol acetate, are mixed with 110.50 parts by weight of the polyisocyanate of Example 5.
The mixture has a viscosity of about 25 seconds, as determined in a 4 mm DIN cup (DIN 53 211). This viscosity makes the mixture suitable for spraying, although it may be adjusted to the required level by adding, or reducing the quantity of, ethyl glycol acetate. This lacquer mixture has a processing time of 2 hours. Properties of the lacquer film: 7.5 mm Erichsen indentation DIN 53 156, pendulum hardness (according to Konig) DIN 53 157, 218 seconds. The lacquer is dried for 30 minutes at 120° C.
EXAMPLE 19
To prepare a lacquer, 154 parts by weight of a 65% solution of a polyester prepared from phthalic acid and trimethylol propane (8% OH) in ethyl glycol acetate, 8 parts by weight of zinc octoate (8% of Zn) in the form of a 10% solution in xylene, 100.1 parts by weight of titanium dioxide and 119.8 parts of ethyl glycol acetate, are mixed with 100.1 parts by weight of the polyisocyanate of Example 6.
The lacquer thus prepared has a viscosity of 25 seconds, as measured in a 4 mm DIN cup (DIN 53 211), for a solids content of 62.3%. The viscosity may be adjusted by the quantity of ethyl glycol acetate used for roll coating, two-component hot spraying or for conventional spread-coating and spray-coating techniques. The lacquer has a processing time of about 5 hours. The lacquer is dried for up to 30 minutes at 120° C.
Properties of the lacquer film:
Erichsen indentation DIN 53 156 8 mm
pendulum hardness (according to Konig) DIN 53 157 - 210 seconds.
EXAMPLE 20
In a 1.5 liter capacity stirrer-equipped apparatus, 1682 g of hexamethylene diisocyanate (10 mols) and 84 g of α-aminoisobutyronitrile (1 mol) are slowly heated to 160° C. in the presence of 1 ml of triethylamine. After stirring for 10 minutes at that temperature, the excess hexamethylene diisocyanate is removed by thin-layer distillation at 180° C./0.2 Torr.
577 g of a polyisocyanate having the following idealized structure are obtained: ##STR22##
η 25 ° C. : 11,320 cP
NCO calculated: 21.4%, found: 21.6%.
EXAMPLE 21
2523 g of hexamethylene diisocyanate (15 mols) and 126 g of α-aminoisobutyronitrile (1.5 mols) are reacted with one another in the same way as described in Example 20, but in the absence of a catalyst. Thin-layer distillation gives 603 g of a reaction product having the following idealized structure: ##STR23##
η 25 ° C..: 5850 cP
NCO calculated: 20.0%, found: 20.1%
EXAMPLE 22
98 g of β-methyl aminoisobutyronitrile (1 mol) are added dropwise at 40° C. to 1680 g of hexamethylene diisocyanate (10 mols). After the exothermic reaction has abated, the reaction mixture is briefly heated to 160° C. and, after cooling, is subjected to thin-layer distillation at 180° C./0.2 Torr in order to remove the monomeric hexamethylene diisocyanate. 430 g of a polyisocyanate having the following idealized structure are obtained: ##STR24##
η 25 ° C. : 15,400 cP
NCO calculated: 19.3%, found: 18.8%
EXAMPLE 23
11.2 g of α-ethyl aminoisobutyronitrile (0.1 mol), containing 0.1 ml of triethylamine and 0.1 ml of zinc octoate, are added dropwise at room temperature to 168 g of hexamethylene diisocyanate (1 mol). After the exothermic reaction has abated, the mixture is briefly heated to 140° C. and subsequently subjected to thin-layer distillation at 170° C./0.1 Torr. 41 g of polyisocyanate having the following idealized structure are obtained: ##STR25##
η 25 ° C. : 21,200 cP
NCO calculated: 18.7%, found: 18.4%.
EXAMPLE 24
840 g of hexamethylene diisocyanate (5 mols) and 62 g of 1-amino-1-cyanocyclohexane are reacted in the same way as described in Example 21 and the reaction product freed from the excess monomer by thin-layer distillation. 218 g of a polyisocyanate having the following idealized structure are obtained: ##STR26##
η 25 ° C. : 16,700 cP
NCO calculated: 18.2%, found: 18.4%.
EXAMPLE 25
840 g of hexamethylene diisocyanate (5 mols) and 69 g of 1-methyl amino-1-cyanocyclohexane (0.5 mol) are mixed and, after the exothermic reaction has abated, briefly heated to 150° C. After cooling, the excess hexamethylene diisocyanate is removed by repeated extraction with cyclohexane. 225 g of a polyisocyanate having the following idealized structure are obtained: ##STR27##
η 25 ° C. : 25,000 cP
NCO calculated: 17.7%, found: 17.3%.
EXAMPLE 26
0.1 ml of triethylamine and 0.1 ml of zinc octoate are added to 840 g of hexamethylene diisocyanate (5 mols), followed by the gradual dropwise addition at room temperature 103 g of 1-cyclohexyl amino-1-cyanocyclohexane (0.5 mol). After the exothermic reaction has abated, the reaction mixture is heated for 10 minutes to 160° C., followed by the addition of 0.5 ml of benzoyl chloride. After cooling, the reaction product is extracted with cyclohexane and petroleum ether. 253 g of a polyisocyanate having the following idealized structure are obtained: ##STR28##
η 25 ° C. : 34,000 cP
NCO calculated: 15.5%, found: 16.0%.
EXAMPLE 27
1680 g of hexamethylene diisocyanate (10 mols) are introduced into a 3 liter capacity three-necked flask, followed by the dropwise addition over a period of 30 minutes of 84 g of 3-methyl aminopropionitrile. The internal temperature rises to 52° C. After the exothermic reaction has abated, 1 g of diazabicyclooctane and 1 ml of zinc octoate are introduced into the reaction mixture, followed by heating for 1 hour to 160° C. Removal of the monomeric hexamethylene diisocyanate by thin-layer distillation gives 380 g of a polyisocyanate having the following idealized structure: ##STR29##
η 25 ° C. : 1950 cP
NCO calculated: 20%, found: 19.6%.
EXAMPLE 28
841 g of hexamethylene diisocyanate (5 mols) are reacted with 35.5 g of β-aminopropionitrile (0.5 mol) in the same way as described in Example 27. 329 g of a polyisocyanate having the following idealized structure are obtained by way of the urea stage: ##STR30##
η 25 ° C. : 3852 cP
NCO calculated: 20.7%, found: 20.4%.
EXAMPLE 29
504 g of hexamethylene diisocyanate (3 mols) are reacted with 46.8 g of N-cyanoethyl aminoacetic acid ethyl ester (0.3 mol) in the same way as described in Example 27. Before thin-layer distillation, the catalysts are blocked by the addition of 0.5 ml of acetyl chloride. 150 g of a polyisocyanate having the following idealized structure are obtained. ##STR31##
η 25 ° C. : 460 cP
NCO calculated: 17.6%, found: 17.4%.
It is to be understood that any of the components and conditions mentioned as suitable herein can be substituted for its counterpart in the foregoing examples and that although the invention has been described in considerable detail in the foregoing, such detail is solely for the purpose of illustration. Variations can be made in the invention by those skilled in the art without departing from the spirit and scope of the invention except as it may be limited by the claims. | The present invention relates to a new organic heterocyclic isocyanate which is the reaction product of an organic diisocyanate and an amino or hydroxy nitrile. The invention also relates to a process of producing such isocyanates by reacting an excess of the diisocyanate with the nitrile under conditions under which the nitrile will not decompose and then maintaining the reaction mixture at an elevated temperature until the isocyanate nitrile adduct cyclizes. The reaction may be carried out in the presence of a catalyst for isocyanate addition reactions. Additionally, the invention relates to a process for the production of polyurethane by the reaction of the heterocyclic isocyanates with compounds carrying at least two isocyanate reactive hydrogen atoms per molecule. | 2 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a national phase filing under 35 U.S.C. §371 and claims priority to International Application No. PCT/EP2005/007274 which has an International filing date of Jul. 6, 2005, and which designated the United States of America and which claims priority to German Application No. 10 2004 034 141.9, filed Jul. 15, 2004, the entire disclosures of which are hereby incorporated herein by reference.
BACKGROUND OF THE INVENTION
This invention relates to the use of certain fatty alcohol sulfates for cleaning boreholes, drilling equipment and drill cuttings and to processes for cleaning boreholes, drilling equipment and drill cuttings.
In the drilling and development of oil and gas occurrences, cleaning steps have to be introduced at various stages to ensure problem-free drilling and production. Thus, after the actual drilling process, the borehole has to be prepared for the production of oil or gas (completion). To this end, an outer tube or casing has to be introduced and cemented in place to stabilize the borehole. The cement is passed through the casing in an aqueous liquid form, emerges at the lower end of the casing and hardens between the borehole wall and the casing. To guarantee optimal cementing, the borehole wall and the casings have to be freed from adhering residues of the drilling mud and adhering fine-particle solids. If this is not done, the layer of concrete is in danger of developing voids or channels which reduce the stability of the concrete. In addition, residues of the drilling mud and the cement together can form a gelatinous mass which prevents the cement from setting so that the stability of the cement jacket is further reduced.
After the casing has been introduced into the borehole, the actual production tube, which is smaller in diameter than the casing, is installed. In addition, a sealing fluid (or packer fluid as it is also known) is introduced between the production tube and the inner wall of the casing. Before this packer fluid is introduced, the annular space between the casing and the production tube is cleaned. In particular, all fine-particle solids still adhering to the wall of the casing or production tube have to be removed to guarantee the performance of the packer fluid.
The choice of the cleaning composition to perform the functions mentioned above is also determined by the nature of the drilling mud used. In principle, drilling muds are divided into water-based types and oil-based types. Oil-based drilling muds are mainly used today either as so-called “true oil muds”, i.e. muds which contain little if any dispersed water, or as so-called invert muds which contain between 5 and 45% by weight of water as dispersed phase, i.e. which form a w/o emulsion. In addition, there are water-based o/w emulsions which contain a heterogeneous finely disperse oil phase in a continuous aqueous phase. Petroleum products, such as mineral or diesel oils, are normally used as the oil phase. However, increasingly more stringent ecological requirements have recently led to the development of synthetic oil phases, for example containing esters of certain fatty acids. Drilling muds based on such ester oils are described, for example, in European patents 386 636, 374 671 and 374 672 and show distinctly improved behaviour compared with petroleum products in regard to their biological degradability and toxicity. Where drilling muds based on synthetic esters are used, the formation of tacky residues on metal surfaces and on the borehole wall are occasionally observed and can also lead to troublesome deposits.
In the same way as the cement used for the cementing process, the cleaning compositions are pumped downwards through the drill pipe in liquid form, emerge at the bottom of the borehole and are forced upwards through the annular space between the tube and the borehole wall. They detach residues of the drilling muds and solid particles adhering to the surfaces and remove them from the borehole. One such process is described in detail, for example, in WO 94/29570. The compositions are normally used in the form of aqueous or non-aqueous solutions or dispersions. However, they may also be added to the drilling mud in concentrated, solid or liquid form. Cleaning compositions for the functions described above may be, for example, mixtures of citric acid, pyrophosphate and potassium salts used in solid or dissolved form. These compositions are suitable both for true oil muds and for invert muds.
WO 95/17244 describes a composition for cleaning surfaces soiled with oil which contain surfactants with HLB values of at least 8 in combination with an oil. Ethoxylated sorbitan fatty acid esters are mentioned as preferred surfactants. Now, although compositions based on ethoxylated sorbitan fatty acid esters develop a favourable cleaning effect, their biological degradability and toxicity do not meet all the requirements of increasingly more stringent environmental legislation.
WO 98/19043 discloses specific soya polyol alkoxylates as highly effective cleaning agents for boreholes and drilling equipment. However, there remains a constant need to improve the environmental compatibility of cleaning compositions and, in particular, to reduce their toxicity and to improve their biodegradability while at the same time increasing their cleaning performance.
Accordingly, the problem addressed by the present invention was to provide cleaning compositions for boreholes, drilling equipment or drill cuttings which would show improved ecological compatibility, above all reduced toxicity, in relation to known compositions for at least the same cleaning performance.
BRIEF SUMMARY OF THE INVENTION
It has been found that specific fatty alcohol sulfates solve the problem stated above. In a first embodiment, the present invention relates to the use of compounds corresponding to general formula (I): R—O—SO 3 − Li + , in which R is a saturated, unsaturated, branched or linear alkyl group containing 8 to 22 carbon atoms, for cleaning boreholes, drilling equipment and drill cuttings. The key element of the present technical teaching is the limitation to lithium salts because it is only lithium salts which have the required properties.
DETAILED DESCRIPTION OF THE INVENTION
Alkyl and/or alkenyl sulfates, which are often also referred to as fatty alcohol sulfates, are understood to be the sulfation products of primary alcohols which correspond to formula (I). Fatty alcohol sulfates are, generally, a group of anionic surfactants with the general formula: R—O—SO 3 X which are obtained, for example, by reaction of fatty alcohols with conc. sulfuric acid, gaseous sulfur trioxide, chlorosulfonic acid or amidosulfonic acid. Fatty alcohol sulfates show good solubility in water, little sensitivity to hardness and—given an adequate chain length—high washing performance. Typical examples of alkyl sulfates which may be used in accordance with the invention are the sulfation products of caproic alcohol, caprylic alcohol, capric alcohol, 2-ethyl hexyl alcohol, lauryl alcohol, myristyl alcohol, cetyl alcohol, palmitoleyl alcohol, stearyl alcohol, isostearyl alcohol, oleyl alcohol, elaidyl alcohol, petroselinyl alcohol, arachyl alcohol, gadoleyl alcohol, behenyl alcohol and erucyl alcohol and the technical mixtures thereof obtained by high-pressure hydrogenation of technical methyl ester fractions or aldehydes from Roelen's oxo synthesis. Alkyl sulfates based on C 8-16 and, more particularly, C 8-14 fatty alcohols are particularly preferred. Both pure compounds and mixtures, including technical mixtures, of different compounds corresponding to formula (I) may be used in accordance with the invention.
Fatty alcohols which have C 12 alkyl chains, i.e. which are based on dodecyl alcohol (trivial name: lauryl alcohol), are particularly preferred. Compounds of formula (I), in which at least 50% by weight of the substituent R has a C 12 chain, are particularly preferred. Compounds in which the percentage content of C 12 is greater than 50% by weight are most particularly preferred. In principle, however, the substituents R in formula (I) may also be unsaturated and/or branched.
The lithium salts are used in the form of aqueous solutions. In a preferred embodiment, the solutions contain the salts of formula (I) in quantities of 1 to 35% by weight and preferably in quantities of 5 to 25% by weight. The quantity may vary and is adapted to the nature and extent of the soiling/contamination.
The lithium salts of the fatty alcohol sulfates are used in particular for cleaning boreholes. More particularly, the walls of the borehole itself or even production tubes or casing walls can be cleaned using the compounds according to the invention. Drilling equipment in the context of the invention includes, for example, pipelines and tools which are used in drilling operations and which come into contact with other drilling muds and/or crude oil. In addition, the lithium salts may also be used for cleaning drill cuttings. Drill cuttings accumulate during the drilling process and, in the case of offshore drilling, have to be dumped on the seabed in the vicinity of the drilling platform which can lead to the large-scale introduction of mineral oil into the environment. In order largely to avoid ecological damage to the sea, the cuttings are cleaned and freed beforehand from residues of the drilling mud.
The compositions according to the invention may be used in all cleaning processes known to the expert which are involved in geological drilling both offshore and on land. These cleaning processes include, in particular, the removal of paraffin deposits from borehole walls. Boreholes are normally cleaned by a cleaning fluid being pumped under pressure through the borehole and the deposits being removed from the walls of the borehole by the cleaning fluid. The deposits are then transported from the borehole with the fluid. Accordingly, the present invention also relates to a process for cleaning boreholes in which one of the compositions according to the invention is pumped through the borehole by the method described above.
The compositions may also be used for cleaning preferably oil-covered articles, such as tools, pipelines or drill cuttings which accumulate in geological drilling. To this end, an aqueous solution according to the invention is sprayed onto or applied to the surfaces of the articles or the articles to be cleaned are immersed in the compositions. The oil and other soil types are thus removed from the surfaces. The surfaces are then contacted with water so that the compositions are removed with the soils. For example, the surfaces are sprayed with a jet of water.
Accordingly, the present invention also relates to a process for cleaning the surfaces of drilling equipment or drill cuttings in which the surfaces are first contacted with a cleaning fluid and are then sprayed with water, the lithium salts described above in the form of aqueous solutions being used as the cleaning fluid.
EXAMPLES
The following examples are illustrative of the invention and should not be construed as limiting the scope thereof.
Example 1
Comparing Lithium and Sodium Salts
Measuring the Cleaning Effects
Tests were conducted with the lithium salts according to the invention and the corresponding sodium salts. To this end, quantities of 8 g of a drilling fluid were applied with a brush to the inside of a measuring beaker weighed beforehand. 200 ml of the 5% by weight aqueous cleaning solution were then poured into the beaker, followed by shaking by hand for 3 minutes.
The glass beaker was then placed upside down on a filter paper for 2 minutes. The weight of the measuring beaker was then determined. The reduction in weight is a measure of the cleaning effect. If, theoretically, the measuring beaker reached the weight before the measurement, this would be evaluated as 100% cleaning performance.
The drilling fluid had the following composition:
Ester oil C 8-14 fatty acid-2-ethylhexyl ester
250
ml
Emulsifier (amidoamine)
10
g
Fluid loss additive (hydrophobicized lignite)
10
g
Lime
1.2
g
CaCl 2 •2H 2 O
27
g
Weighting agent (calcium carbonate)
100
g
BaSO 4
100
g
Hymond Prima Clay
43
g
Water
84
g
The oil/water ratio was 75:25. The drilling fluid was aged for 16 h at 200° F. (93° C.). The results of the test are set out in Table 1.
TABLE 1
Comparing Lithium and Sodium Salts
Name
Product
Performance in %
V1
Na lauryl sulfate C12/14, 90% (active
75
substance content)
V2
Na lauryl sulfate C12, 95% (active
62
substance content)
E1
Lithium lauryl sulfate, C8-12, 30% (active
88
substance content)
The products were used as 5% aqueous solutions. The lithium salts according to the invention show a distinctly increased cleaning performance for a reduced input of active substance.
Example 2
Comparing Cleaning Effect of Lithium Lauryl Sulfate v. Soya Polyol Ethoxylate and C8-10 Alkyl-1,5-Glucoside
In another test similar to that described above, the lithium salts according to the invention were tested for cleaning performance in comparison with soya polyol ethoxylates (according to WO 98/19043) and commercially available alkyl polyglycosides. The results are set out in Table 2.
TABLE 2
Cleaning Effect of Lithium Lauryl Sulfate v. Soya Polyol
Ethoxylate And C8-10 Alkyl-1,5-Glucoside
Name
Product
Performance in %
V3
Soya polyol ethoxylate (5% active
58
substance)
V4
C8-10 alkyl-1,5-glucoside (63% active
62
substance)
E1
Lithium lauryl sulfate, C8-12, 30% in water
88
Example 3
Comparing Toxicity of Lithium Lauryl Sulfate v. Soya Polyol Ethoxylate and C8-10 Alkyl-1,5-Glucoside
Toxicity Measurements
The toxicity of products V3, V4 and the salt E1 according to the invention was measured on Skeletonema costatum (to ISO 10253 1988) and Corophium volutator (to OSPRACOM Guidelines (1995)—A Sediment Bioassay Using an Amphipod). An aerobic degradation test was also carried out (Marine Bodies ISO/TC 147/SC 5/WG 4 N 141).
The results are set out in Table 3.
TABLE 3
Toxicity of Lithium Lauryl Sulfate v. Soya Polyol Ethoxylate
And C8-10 Alkyl-1,5-Glucoside
Corophium
Aerobic
Skeletonema
volutator
degradation
Cleaner
72 h EC 50 (mg/l)
10 d, LC 50 (mg/kg)
(28 d) in %
V3
16
1888
36
V4
20
None after 433
38
E1
33
6585
98 | The invention relates to a process of cleaning boreholes, boring equipment and borings with an aqueous cleaning of one more lithium salts of alkyl sulfates of formula (I):
R—O—SO 3 − Li + (I)
in which R is a saturated, unsaturated, branched or linear alkyl group containing 8 to 22 carbon atoms, preferably the lithium salts of alkyl sulfates are comprised of a mixture of those in which R is a saturated, linear alkyl groups having 8 to 14 carbon atoms. | 2 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims the benefit of U.S. Provisional Patent Application No. 60/451,060 filed Feb. 26, 2003.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to integrated circuit semiconductor diodes and transistors.
[0004] 2. Prior Art
[0005] Semiconductor devices tend to be divided into discrete components and integrated circuits. The discrete devices include single function components such as bipolar transistors, junction field effect transistors, surface field effect transistors, silicon controlled rectifiers, etc. and some integrated components such as insulated gate bipolar transistors. One characteristic that is common to all the discrete components is the lack of external power supply requirements.
[0006] Recently a new form of discrete circuit has entered the market; a highly efficient diode made from surface field effect transistors, an integrated circuit diode (ICD). This circuit in its present form (passive form) does not utilize any on-chip drive circuitry; however, with the addition of either external or internal power, these circuits can improve their performance dramatically by utilizing on-chip circuitry to actively drive the transistor gates (active form).
[0007] Utilizing external power for this purpose tends to be less attractive because of the added circuit board complexity. However, it does have the advantage of not altering the external signal while drawing the charge needed for the onboard supply voltage. In most applications, the added convenience of the self-powered circuit would be advantageous.
[0008] In typical semiconductor diodes, conduction in the forward direction is limited to leakage current values until the forward voltage bias reaches a characteristic value for the particular type of semiconductor device. By way of example, silicon pn junction diodes don't conduct significantly until the forward bias voltage is approximately 0.6 to 0.7 volts. Many silicon Schottky diodes, because of the characteristics of the Schottky barrier, can begin to conduct at lower voltages, such as 0.4 volts. Germanium pn junction diodes have a forward conduction voltage drop of approximately 0.3 volts at room temperature. However, the same are rarely used, not only because of their incompatibility with silicon integrated circuit fabrication, but because of temperature sensitivity and other undesirable characteristics thereof.
[0009] In some applications, diodes are used not for their rectifying characteristics, but rather to be always forward biased to provide their characteristic forward conduction voltage drop. For instance, in integrated circuits, diodes or diode connected transistors are frequently used to provide a forward conduction voltage drop substantially equal to the base-emitter voltage of another transistor in the circuit.
[0010] In circuits that utilize the true rectifying characteristics of semiconductor diodes, the forward conduction voltage drop of the diode is usually a substantial disadvantage. By way of specific example, in a DC to DC step-down converter, a transformer is typically used wherein a semiconductor switch controlled by an appropriate controller periodically connects and disconnects the primary of the transformer with a DC power source. The secondary voltage is connected to a converter output, either through a diode for its rectifying characteristics, or through another semiconductor switch. The controller varies either the duty cycle or the frequency of the primary connection to the power source as required to maintain the desired output voltage. If a semiconductor switch is used to connect the secondary to the output, the operation of this second switch is also controlled by the controller; one form of this switch configuration circuit is called a synchronous rectifier.
[0011] Use of a semiconductor switch to couple the secondary to the output has the advantage of a very low forward conduction voltage drop, and has the disadvantage of requiring careful timing control throughout the operating temperature range of the converter to maintain the efficiency of the energy transfer from primary to secondary. Timing of the switching action for the primary versus the secondary is critical and must take into account the phase delays of the transformer and other elements. These circuits are obviously very costly.
[0012] The use of a semiconductor diode for this purpose has the advantage of eliminating the need for control of a secondary switch, but has the disadvantage of imposing the forward conduction voltage drop of the semiconductor diode on the secondary circuit. This has at least two very substantial disadvantages. First, the forward conduction voltage drop of the semiconductor diode device can substantially reduce the efficiency of the converter. For instance, newer integrated circuits commonly used in computer systems are designed to operate using lower power supply voltages, such as 3.3 volts, 3 volts and 2.7 volts. In the case of a 3 volt power supply, the imposition of a 0.7 volt series voltage drop means that the converter is in effect operating into a 3.7 volt load, thereby limiting the efficiency of the converter to 81%, even before other circuit losses are considered.
[0013] Second, the efficiency loss described above represents a power loss in the diode, resulting in the heating thereof. This limits the power conversion capability of an integrated circuit converter, and in many applications requires the use of a discrete diode with a heat sink of adequate size, increasing the overall circuit size and cost. Obviously any improvement in the forward voltage drop will have a major impact on the overall circuit performance.
[0014] Another commonly used circuit for AC to DC conversion is the full wave bridge rectifier usually coupled to the secondary winding of a transformer having the primary thereof driven by the AC power source. Here two diode voltage drops are imposed on the peak DC output, making the circuit particularly inefficient using conventional diodes, and increasing the heat generation of the circuit requiring dissipation through large discrete devices, heat dissipating structures, etc. depending on the DC power to be provided.
[0015] Therefore, a semiconductor diode having a low forward conduction voltage drop would be highly advantageous to use as a rectifying element in circuits wherein the diode will be subjected to both forward and reverse bias voltages from time to time. While such a diode may find many applications in discrete form, it would be further desirable for such a diode to be compatible with integrated circuit fabrication techniques so that the same could be realized in integrated circuit form as part of a much larger integrated circuit. Further, while reverse current leakage is always undesirable and normally must be made up by additional forward conduction current, thereby decreasing circuit efficiency, reverse current leakage can have other and more substantial deleterious affects on some circuits. Accordingly, it would also be desirable for such a semiconductor diode to further have a low reverse bias leakage current.
[0016] The ICD in its passive form provides lower forward voltages than Schottky diodes, with enhanced reliability at a competitive price. They also provide an attractive alternative for the higher voltage portion of the synchronous rectifier market; however, they are not able to replace the entire synchronous rectifier market.
BRIEF SUMMARY OF THE INVENTION
[0017] The present invention provides circuits and methods that, when integrated into an IC, will provide an on-chip power source to run control circuits on the IC. It draws its power from the applied signal during the “off” portion of the IC's cycle. For example, in the case of an IC behaving as a rectifier, the circuit will utilize the large reverse voltage during the off state of the rectifier to draw power for the supply. In the case of an IC behaving as a transistor, which does not have a reversal of the applied potential, the power supply will draw its power during the “off” state when a large bias is formed across the IC.
[0018] During the “on” state of these IC's, the power supply will provide power to drive the control circuits which can be used to generate a more conductive “on” state, and a lower leakage “off” state. In the case of an ICD, the forward voltage can be significantly reduced, to a level equivalent to or better than that of a synchronous rectifier. In the case of a surface field effect transistor IC, the gate drive can be substantially enhanced, providing a reduced “on resistance” which equates to forward voltage reduction.
BRIEF DESCRIPTION OF THE DRAWINGS
[0019] [0019]FIG. 1 is a schematic drawing of the prior art ICD. “Signal 1 ” (Cathode) and “Signal 2 ” (Anode) are the normal input signals, such as a sine wave or square wave, to the diode. The “Passive ICD” is an n-channel MOSFET device that behaves as a diode.
[0020] [0020]FIG. 2 presents the addition of a capacitor and diode to the ICD chip. This allows the capacitor to charge and act as a battery, powering the control circuitry to run the ICD gate.
[0021] [0021]FIG. 2A presents the same concept as FIG. 2 except the diode is moved to the other side of the capacitor. This inverts the polarity of the sense signal, hence the − and + signs in FIGS. 2 and 2A.
[0022] [0022]FIG. 3 presents the same concept except driving a metal oxide semiconductor field effect transistor. This Integrated Circuit MOSFET (ICM) device has external inputs corresponding to the source, drain, and gate.
[0023] [0023]FIGS. 4 and 4A present control circuits used with the + and − sense configurations, respectively.
[0024] [0024]FIG. 5 presents the same type of drive circuitry as in FIGS. 4 and 4A except as modified for an n-channel MOSFET.
[0025] [0025]FIG. 6 presents a sample control circuit for a p-channel MOSFET.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0026] Referring to FIG. 1, a prior art schematic diagram of an ICD (integrated circuit diode) is presented. This device acts as a low forward voltage diode because of the gate connections, and the depletion threshold voltage. It is specifically designed to handle alternating polarities. It is obvious that the addition of an external power supply and control logic would greatly enhance the functionality of this device by allowing the gate to be driven well above the drain potential when conducting.
[0027] The device shown in FIG. 1 is an n-channel device. Normally, in a conventional field effect device, the body or backgate is connected to the source of the charge carriers when the device is turned on. In that regard, the source and drain labels, as used herein refer to the source being that region which is the source of the charge carriers when the device is turned on or conducting, and with the drain being the other region of the same conductivity type. Therefore, the charge carriers flow from the source through the channel to the drain during conduction. In the case of the ICD of FIG. 1, conduction occurs when signal 2 is a higher voltage than signal 1 . Since the Figure depicts an n-channel device, and with the foregoing definition of source and drain, it will be noted that in the case of the passive integrated circuit diode (ICD), the body or backgate of the ICD is connected to the drain, not the source. Also an ICD characteristically has a slightly negative threshold. Thus, for an ICD, when the source and drain are at the same voltage, the channel is somewhat conductive, though the current is zero because the source and drain are at the same voltage. For an n-channel ICD, when the drain voltage is raised above the source voltage, the conduction along the channel will cause an IR drop in the channel, with the channel close to the source having a voltage close to the source voltage. Thus the gate-channel voltage increases in that region of the channel, reducing the channel resistance. The effect is progressive along the channel, so that most of the channel becomes closer to the source voltage and thus more highly conductive. Consequently the overall channel resistance becomes lower and lower as the drain voltage increases, supporting high current levels with a relatively low forward voltage conduction drop. On the other hand, when the source voltage is above the drain voltage, conduction in the channel causes the channel voltage next to the source to be close to that of the source, and thus to have a gate channel voltage which causes a high channel resistance in that area. Thus while leakage will increase with an increasing reverse bias voltage on the ICD, the resistance of the channel will be high, and resistance of the channel will increase with increasing reverse bias voltage, thereby increasing the resistance of the channel with increasing reverse bias voltage, thereby limiting the rise in the leakage current with increasing reverse bias voltage. This is the standard Id/Vds behavior of a MOSFET with a constant gate potential.
[0028] In usual diode terms, the Anode of a diode is the positive terminal during forward conduction, and the Cathode is the negative terminal. For the n-channel ICD the forward conduction Drain corresponds to the Anode, and the Source which is the n-type substrate to the Cathode. If one were to build a p-channel ICD the Anode would correspond to the Source which is the p-type substrate, and the Cathode to the Drain. Due to carrier mobility differences, our discussion of the ICDs will focus on the n-channel device with the understanding that changing material types and circuit polarities would produce a p-channel ICD.
[0029] For those skilled in the art, it is apparent that a JFET could be substituted for the MOSFET to form the ICD and the ICM could also be made in a JFET flavor.
[0030] In the disclosure to follow, passive n-channel ICDs and active n-channel and p-channel ICMs are referred to, the active devices being three terminal devices with separate gate connections. These devices assume a MOSFET design and have the body or backgate of the ICDs connected to the drain for the ICDs and the source for the ICMs.
[0031] The use of discrete MOSFETs driven by control logic circuitry is well known in the art; for example, synchronous rectifiers. The addition of the control logic to an IC is also well known, as is the integration of on chip power supplies such as the back gate power supplies on IC's which provide a negative potential to the substrate to control transistor thresholds; however, the integration of a selfcontained power supply into an IC without external power supply connections is new to the art. The present invention incorporates circuitry to the IC for the purpose of on-chip charge storage, acting as an effective battery to power the control logic. The energy stored in the battery is extracted from the actual signal lines during the “off” state of the IC.
[0032] [0032]FIG. 2 is a schematic representation of an active ICD utilizing control circuitry to power its gate electrode. The energy to drive the control circuitry is extracted from the signal lines by the addition of a capacitor and a diode. The diode allows the capacitor to charge during the reverse bias condition for the ICD (off state, no current flow but high reverse voltage) and prevents a discharge of the capacitor when the potential across the ICD drops below the charging potential, whether or not the polarity actually reverses.
[0033] As can be seen, if there is an alternating voltage across the diode and a load (load is not shown) the peak to peak voltage will be stored on the capacitor with the positive potential at the signal 1 side, and the negative potential at the signal 2 side. This effectively acts as a half wave rectifier circuit. Also, note that the control circuitry will require a sense line to synchronize its control activity with the applied signal. This sense line must be isolated from the charge storage device. In the case of FIG. 2, the diode serves as the isolation, allowing the sense potential to follow signal 2 independently of the capacitor.
[0034] [0034]FIG. 2A presents the configuration of FIG. 2 except the diode and capacitor are reversed in position. This moves the sense connection to signal 1 ; however, the polarity across the capacitor is not reversed. This configuration is arbitrarily identified with a “− sense” notation relative to FIG. 2 with a “+ sense” notation. The function of the finished ICD to the external circuit is the same for both the − and + sense configurations. It is only an internal design difference which distinguishes the two senses.
[0035] It is apparent that if a standard MOSFET is substituted into this circuit, implying that there is no change in the polarity of the signal voltage, the diode can be reversed so that it will charge the capacitor during the off state of the transistor. See FIG. 3 compared to FIG. 2. This will reverse the polarity on the capacitor, requiring appropriate modification to the control circuitry. This configuration would allow a MOSFET transistor with no additional power connections to function with a very low apparent gate drive; utilizing that drive to trigger a much larger drive from the control circuitry. One of the design problems associated with power MOSFETs is providing adequate drive current for their large gate structures. The ICM eliminates this concern.
[0036] The control circuit may take many forms. The examples presented here are for demonstrating the application of the invention rather than a specific control circuitry. FIGS. 4 and 4A use identical control circuitry. Because of the different configuration of the diode and capacitor, the supply lines are routed differently, and the sense line has the polarity reversed. FIG. 4 uses the +sense configuration of FIG. 2 while FIG. 4A uses the − sense configuration of FIG. 2A.
[0037] The control circuit is designed to take the sense input, and use it to control the potential applied to the N-channel MOSFET gate. Resistors R 3 and R 4 and transistors M 1 and M 2 form a bistable latch. The state of the latch is determined by the potential of the sense signal (trigger signal in FIGS. 4 and 4A). Resistors R 3 and R 4 are pull-up resistors that provide power to maintain the state of the latch, while limiting the charge drain on the internal power supply. In FIG. 4, a positive trigger signal turns on transistor M 1 , which in turn turns off transistor M 2 . This causes the resistor R 4 -transistor M 2 node to go toward V+. The Zener diode limits the extent of this voltage excursion to its rated zener voltage. This positive voltage turns on transistor M 3 , whose source is connected to the gate of the active ICD. When the potential of the source rises to the zener potential, the charge transfer stops, limiting the positive potential applied to the active ICD gate to the zener voltage plus a small delta.
[0038] The configuration of transistor M 3 with the zener diode prevents excessive voltage on the gate of the ICD that could potentially cause a gate oxide rupture. When the trigger signal changes polarity, the state of the latch is reversed so that the gate of transistor M 3 is driven negative, at the same time, the gate of transistor M 4 is driven positive so that the gate of the ICD, and the source of transistor M 3 are pulled negative.
[0039] As can be seen, the gate of the active ICD is driven between an off signal (V−), and a positive voltage set by the zener diode. This allows the on state of the ICD to have a much lower voltage drop than it would in the passive state of FIG. 1. Looking at FIGS. 4 and 4A, it can be seen that in both cases the V+ and V− signals are routed to the same points within the control circuit, the V+ goes to the resistor side of the latch, and the V− to the MOSFET side of the latch. The sense signal, however, is routed to the opposite latch polarity. In FIG. 4 it goes to the drain of transistor M 2 , while in FIG. 4A, it goes to the drain of transistor M 1 . This is due to the polarity reversal of the sense signal. In both circuits, the forward condition (ICD gate turned on) corresponds to Signal 1 being negative with respect to Signal 2 .
[0040] While the shaping characteristics of the latch are convenient, in many cases the full latch is not required for the circuit to function correctly. For example, in FIG. 4A, if resistor R 3 and transistor M 1 were eliminated, the circuit would still behave properly with a well behaved input signal.
[0041] [0041]FIG. 5 demonstrates the same control circuit with an N-channel MOSFET. Note that the diode has been reversed so that the voltage across the ICM while it is off will charge the capacitor. The sense signal is now the gate input electrode.
[0042] [0042]FIG. 6 demonstrates the same control circuit, except for a p-channel MOSFET device. Note that all the MOSFETs are now p-channel devices and the polarity of the voltage to the control circuit is reversed.
[0043] In the ICM of FIGS. 5 and 6, the control circuit receives a gate control signal and provides an enhanced gate control signal to the field effect transistor. That enhanced signal may be enhanced in terms of voltage swing (larger swing), or in current drive to rapidly charge and discharge the transistor gate capacitance, particularly in the case of power transistors, in speed of the gate drive transition for increasing the speed of turn on and turn off, or any combination of these or other parameters. Also, the ICM may be used in a larger integrated circuit, or may be packaged as a three terminal device and used in place of a conventional FET for its improved performance.
[0044] While certain preferred embodiments of the present invention have been disclosed and described herein, it will be understood by those skilled in the art that various changes in form and detail may be made therein without departing from the spirit and scope of the invention. | A technique, for drawing power from the external signal circuit to power on-chip elements for an integrated circuit diode (ICD), utilizes an integrated diode and capacitor. The capacitor is charged by the external applied voltage during the time the ICD blocks the external current flow. The charged capacitor then acts as a battery to power the on-chip circuits to provide active control for the ICD function. This ICD could be provided as a two terminal discrete diode, or integrated onto a larger IC. This same technique can be utilized for a “self powered” MOSFET IC (ICM), utilizing a low power logic signal to trigger an internal circuit which would provide a much larger gate drive than the logic signal could provide. This could also be provided as discrete three terminal components, or integrated into a larger IC. | 7 |
TECHNICAL FIELD
The invention relates to a process for the production of an optically active alcohol.
BACKGROUND ARTS
Asymmetric ruthenium complexes, rhodium complexes and iridium complexes, which take sulfonyl diamine as a ligand, are useful asymmetric reducing catalysts. These are employed for the asymmetric reduction of a ketone substrate for an efficient production of an optically active alcohol (Patent Literatures 1 and 2).
In Non-patent Literature 1,2-propanol is used as a hydrogen source. This reaction is a reversible equilibrium reaction that gives an optically active alcohol and acetone from ketone substrate and 2-propanol. Therefore, an (S,S) catalyst, for example, reduces acetophenone to give (S)-phenylethanol in a ratio of 99:1 ((S):(R)). However, this reaction preferentially dehydrogenates (S)-phenylethanol in a ratio of 99:1 to give acetophenone, compared to (R)-phenylethanol. Therefore, at initial phase of the reaction, when the concentration of the hydrogen source 2-propanol is high, (S)-phenylethanol and (R)-phenylethanol are produced in the reaction system in a ratio of 99:1. However, when the reaction proceeds and the concentration of (S)-phenylethanol is increased, the reverse reaction will reduce the composition ratio (optical purity) of (S)- and (R)-phenylethanols in the reaction system; their ratio will be reduced to 97:3 at 75% conversion. As being such an equilibrium reaction, in a reaction system where 2-propanol is employed as hydrogen source, in order to obtain an optically active alcohol in high optical purity, there have been problems that there must be a large excessive amount of the hydrogen source 2-propanol than the product optically active alcohol; and that the reaction must be carried out under the condition where the concentration of the ketone substrate is as low as approximately 0.1M.
In order to solve these problems, in Non-patent Literature 2, formic acid is used as the hydrogen source. In this method, formic acid is eliminated from the system as carbon dioxide after providing hydrogen, rendering the reaction irreversible and increasing the optical purity of the produced optically active alcohol. Although using this method, the optical purity and the S/C ratio (substrate/catalyst molar ratio) of the optically active alcohol were improved compared to the reaction using 2-propanol as the hydrogen source, there still is a necessity of improvement, such as in the S/C ratio (substrate/catalyst molar ratio).
Then Non-patent Literature 3 suggested a method to use sodium formate as the hydrogen source under a condition of a two-phase reaction system where water is employed as the solvent. In this method, although there is a large increase in the reaction rate and an improvement in the S/C ratio (substrate/catalyst molar ratio) compared to the reaction using formic acid, the optical purity of the alcohol is decreased. For example, a reaction of an acetophenone gives phenylethanol at 97% ee using formic acid, whereas a two-phase reaction system gives phenylethanol at 95% ee.
Meanwhile, a high catalytic activity of the two-phase reaction system is interpreted to be an effect exhibited by water (Non-patent Literatures 3 and 4), and therefore, in Non-patent Literature 5, many of the approaches for achieving a high optical purity were focused on the structural optimization of the catalyst and the development of an aqueous catalyst, while leaving the condition unchanged that water is present. On the other hand, Non-patent Literature 6 reported as an approach to improve the reacting conditions, a homogenous reaction system in which potassium formate in polyethyleneglycol is used as a hydrogen source. This approach, however, is focused on the recycle of catalyst by retaining the catalyst in polyethyleneglycol phase, and there is no mentioning about any suppressive effect on the racemization of the produced alcohol by the homogenous reaction.
CITATION LIST
Patent Literatures
[Patent Literature 1] JP B No. 2962668
[Patent Literature 2] JP B No. 4090078
Non-patent Literatures
[Non-patent Literature 1] S. Hashiguchi, A. Fujii, J. Takehara, T. Ikariya, R. Noyori, J. Am. Chem. Soc. 1995, 117, 7562
[Non-patent Literature 2] A. Fujii, S. Hashiguchi, N. Uematsu, T. Ikariya, R. Noyori, J. Am. Chem. Soc. 1996, 118, 2521
[Non-patent Literature 3] X. Wu, X. Li, W. Hems, F. Hems, F. King, J. Xiao, Org. Biomol. Chem. 2004, 2, 1818
[Non-patent Literature 4] X. Wu, C. Wang, J. Xiao, Platiunm Metals Rev. 2010, 54, 3
[Non-patent Literature 5] C. Wang, X. Wu, J. Xiao, Chem. Asian, J. 2008, 3, 1750
[Non-patent Literature 6] H. F. Zhou, Q. H. Fan, Y. Y. Huang, L. Wu, Y. M. He, W. J. Tang, L. Q. Gu, A. S. C. Chan, J. Mol. Catal. A: Chem. 2007, 275, 47
SUMMARY OF THE INVENTION
Problems to be Solved by the Invention
Accordingly, an object of the present invention is to solve the problems in the prior arts, and to find a more improved reaction conditions for suppressing the racemization of the product and obtaining an optically active alcohol at a high optical purity.
Means for Solving the Problems
In view of the present circumstances as above, the inventors, through an intensive study for solving above problems, focused not on the tuning of a catalyst but on the optimization of reaction conditions, because changing ligand structure would increase the cost of the catalyst. The inventors then focused on the fact that the optical purity was decreased to 95% ee in the two-phase reaction system of the Non-patent Literature 3 above compared to 97% ee of the Non-patent Literature 2, and then sought for the meanings of this small decrease in optical purity, which was of little interest at the time. Accordingly, the inventors actually carried out reactions using various ketone substrates, and from the results reached the recognition that the type of ketone is a important problem in a two-phase reaction system because the optical purity is decreased by more than 5% ee depending on the type of ketone.
Under this recognition, the inventors further pursued the study and reached the speculation that the reduction in the optical purity of the optically active alcohol produced in a two-phase reaction system is caused as follows: because the produced optically active alcohol and catalyst are in an organic phase whereas the hydrogen source is present in an aqueous phase, the hydrogen source supplied to the catalyst is insufficient during the later reaction, accelerating the dehydrogenation of the optically active alcohol that present nearby the catalyst, resulting in the decrease in the optical purity according to the reaction mechanism described as above. Such an speculation was consistent with the increase in the rate of the racemization when decreasing the stirring rate. Thus, the inventors considered that the problem of the racemization of the optically active alcohol in the two-phase reaction system may be solved, if we could make an asymmetric catalyst and hydrogen source exist in the same phase using a solvent system that is capable of resolving both the formate salt and the asymmetric catalyst, and as a result of further researches completed the invention.
Namely, the present invention is a process for producing an optically active alcohol by reacting a ketone substrate in a solvent(s) using a hydrogen source in the presence of an asymmetric catalyst, wherein:
the asymmetric catalyst is a metal complex represented by the following general formula (I):
wherein,
R 1 and R 2 may be identical or different to each other, and is a hydrogen atom, an alkyl group, a phenyl group which may have one or more substituents, a naphthyl group which may have one or more substituents or a cycloalkyl group which may have one or more substituents, or R 1 and R 2 are bound together to form an alicyclic ring which is unsubstituted or have one or more substituents, R 3 is an alkyl group, a perfluoroalkyl group, a naphthyl group which may have one or more substituents, a benzyl group which may have one or more substituents, a phenyl group which may have one or more substituents or a camphor group which may have one or more substituents, R 4 is a hydrogen atom or an alkyl group, Ar is a benzene which may have one or more substituents or a cyclopentadienyl group which may have one or more substituents, X is an anionic group, M is ruthenium, rhodium or iridium, n denotes 0 or 1, where X is not present when n=0, * denotes an asymmetric carbon;
the hydrogen source is a formate salt; and
the solvent(s), which is(are) capable of dissolving the asymmetric catalyst and the formate salt, is(are) (1) an organic solvent(s) (except polyethylenglycol) and/or (2) an organic solvent(s) (except polyethyleneglycol) and/or a water-miscible aprotic solvent(s), and water.
The invention further relates to said process for producing the optically active alcohol, wherein the organic solvent(s) is(are) a protic solvent(s).
The invention also relates to said process for producing the optically active alcohol, wherein the organic solvent(s) is(are) an alcohol having 1 to 5 carbon atoms.
The invention further related to said process for producing the optically active alcohol, wherein the organic solvent(s) is(are) methanol and/or ethanol.
The invention also related to said process for producing the optically active alcohol, wherein the aprotic solvent(s) is(are) DMF (dimethylformamide) and/or DMSO (dimethylsulfoxide).
The invention further relates to said process for producing the optically active alcohol, wherein the solvent(s) comprise(s) an organic solvent(s) (excluding polyethyleneglycol) and water.
The invention also related to said process for producing the optically active alcohol, wherein the solvent(s) comprise(s) an organic solvent(s) (excluding polyethyleneglycol) and an aprotic solvent(s).
The invention further relates to said process for producing the optically active alcohol, wherein the solvent(s) comprise(s) water and a water-miscible aprotic solvent(s).
The invention also relates to said process for producing an optically active alcohol, wherein the solvent(s) comprise(s) an organic solvent(s) (except polyethyleneglycol), water-miscible aprotic solvent(s) and water.
The invention further relates to said process for producing the optically active alcohol, wherein the formate salt is potassium formate and/or sodium formate.
The invention also related to said process for producing the optically active alcohol, wherein the ketone substrate is a cyclic ketone, a ketone having an olefin moiety, a ketone having an acetylene moiety, a ketone having a hydroxyl group, a ketone having a halogen atom, a diketone, a ketoester or a ketoamide.
The invention further relates to said process for producing the optically active alcohol, wherein the reaction is performed in a homogenous phase.
Also, the invention may be, in one of its embodiments, a process for producing an optically active alcohol by reacting a ketone substrate in a solvent(s) using a hydrogen source in the presence of an asymmetric catalyst, wherein
the asymmetric catalyst is metal complex represented by the following general formula (1):
wherein,
R 1 and R 2 may be identical or different to each other, and is a hydrogen atom, an alkyl group, a phenyl group which may have one or more substituents, a naphthyl group which may have one or more substituents or a cycloalkyl group which may have one or more substituents, or R 1 and R 2 are bound together to form an alicyclic ring which is unsubstituted or have one or more substituents, R 3 is an alkyl group, a perfluoroalkyl group, a naphthyl group which may have one or more substituents, a benzyl group which may have one or more substituents, a phenyl group which may have one or more substituents or a camphor group which may have one or more substituents, R 4 is a hydrogen atom or an alkyl group, Ar is a benzene which may have one or more substituents or a cyclopentadienyl group which may have one or more substituents, X is an anionic group, M is ruthenium, rhodium or iridium, n denotes 0 or 1, where X is not present when n=0. * denotes an asymmetric carbon,
the hydrogen source is a formate salt, and
the solvent(s), which is(are) capable of dissolving the asymmetric catalyst and the formate salt, is (1) an organic solvent(s) (except polyethyleneglycol) and/or (2) water and a water-miscible aprotic solvent(s).
Effects of the Invention
The present invention can solve the problems in the prior arts, suppress the racemization of the product, asymmetrically reduce various ketone substrates at a high efficiency, and give an optically active alcohol at a high purity. The present invention can further facilitate the purification of the produced optically active alcohol without requiring any complicated steps. The present invention can also give an extremely high purity of an optically active alcohol by known methods for purification, without using any special procedures for purification. Note that the aim of using a solvent(s) that is capable of resolving an asymmetric catalyst and a formate salt is to allow the asymmetric catalyst and the hydrogen source to be present within the same phase (existing as a homogenous phase), but not to use it as a hydrogen source.
Specifically, according to the invention, an optically active cyclic alcohol (reducing asymmetrically a cyclic ketone), an optically active alcohol having an olefin moiety or an acetylene moiety (reducing asymmetrically a ketone having an olefin moiety or an acetylene moiety (in particular, a ketone in which α,β-linkage is an olefin moiety or an acetylene moiety)), an optically active alcohol having a hydroxyl group (reducing asymmetrically a ketone having a hydroxyl group), an optically active alcohol having a halogen atom (reducing asymmetrically a ketone having a halogen atom (in particular, a ketone having a halogen atom at α-position)), an optically active chromanol (reducing asymmetrically a chromanone derivative), an optically active diol (reducing asymmetrically a diketone), an optically active hydroxy ester (reducing asymmetrically a ketoester), an optically active hydroxy amide (reducing asymmetrically a ketoamide) can be produced.
DESCRIPTION OF EMBODIMENTS
The process according to the invention to produce an optically active alcohol by reacting a ketone substrate in a solvent(s) using a hydrogen source in the presence of an asymmetric catalyst is to be performed in a solvent(s) that is capable of resolving the asymmetric catalyst and the formate salt.
The asymmetric catalyst used in the method according to the invention is not particularly limited as long as it is capable of asymmetrically reducing a ketone substrate to an optically active alcohol, though it typically is represented by the following general formula (1):
In the general formula (1), R 1 and R 2 are, for example, a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an unsubstituted phenyl group, a phenyl group having an alkyl group having 1 to 5 carbon atoms, a phenyl group having a halogen atom, a phenyl group having an alkoxy group, a naphthyl group which may have one or more substituents and a cycloalkyl group having 3 to 10 carbon atoms, or R 1 and R 2 are bound to each other to form an alicyclic ring which either is unsubstituted or has one or more substituents.
The alkyl group having 1 to 10 carbon atoms is such as, for example, a methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, sec-butyl group and tert-butyl group.
The phenyl group having an alkyl group having 1 to 5 carbon atoms is such as, for example, a 4-methylphenyl group and 3,5-dimethylphenyl group.
The phenyl group having a halogen atom is such as, for example, a 4-fluorophenyl group, 4-chlorophenyl group and 4-trifluoromethylphenyl group.
The phenyl group having an alkoxy group is such as, for example, 4-methoxyphenyl group, 4-ethoxyphenyl group, 4-methoxymethylphenyl group, 3-methoxyphenyl group, 3-ethoxyphenyl group, 3-methoxymethylphenyl group, 2-methoxyphenyl group, 2-ethoxyphenyl group and 2-methoxymethylphenyl group.
The naphthyl group which may have one or more substituents is such as, for example, an unsubstituted naphthyl group, 5,6,7,8-tetrahydro-1-naphthyl group and 5,6,7,8-tetrahydro-2-naphthyl group.
The cycloalkyl group having 3 to 10 carbon atoms is such as, for example, a cyclopropyl group, a cyclopentyl group and a cyclohexyl group.
The alicyclic ring which R 1 and R 2 are bound together to form a ring and which is unsubstituted or have one or more substituents is such as, for example, a cyclopentane ring or a cyclohexane ring which is formed by R 1 and R 2 bound together to form a ring.
Among these, from the viewpoint of being readily-synthesized and commercially available, the substituents for R 1 and R 2 is preferably a hydrogen atom, a phenyl group which may have one or more substituents, a cyclohexane ring formed by R 1 and R 2 bound together to form a ring, more preferably R 1 and R 2 are both phenyl groups or bound together to form a cyclohexane.
In the general formula (1), R 3 is such as, for example, an alkyl group having 1 to 10 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, a benzyl group which may have one or more substituents, a naphthyl group which may have one or more substituents, a phenyl group which may have one or more substituents, and a camphor group which may have one or more substituents.
The alkyl group having 1 to 10 carbon atoms is such as, for example, a methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, sec-butyl group, and tert-butyl group, and the alkyl group may further have one or more substituents, such as, for example, one or more fluorine atoms as a substituent. The alkyl group comprising one or more fluorine atoms is such as, for example, a fluoromethyl group, difluoromethyl group, trifluoromethyl group and a pentafluoroethyl group.
The cycloalkyl group having 3 to 10 carbon atoms is such as, for example, a cyclopropyl group, a cyclopentyl group and a cyclohexyl group.
The benzyl group which may have one or more substituents is such as, for example, an unsubstituted benzyl group and 2,6-dimethylbenzyl group.
The naphthyl group which may have one or more substituents is such as, for example, an unsubstituted naphthyl group, 5,6,7,8-tetrahydro-1-naphthyl group, and 5,6,7,8-tetrahydro-2-naphthyl group.
The phenyl group which may have one or more substituents is such as, for example, an unsubstituted phenyl group, a phenyl group having an alkyl group such as a 4-methylphenyl group, 3,5-dimethylphenyl group, 2,4,6-trimethylphenyl group and 2,4,6-triisopropylphenyl group, a phenyl group having a halogen atom such as a 4-fluorophenyl group, 4-chlorophenyl group and 2,4,6-trichlorophenyl group, a phenyl group having an alkoxy group such as a 4-methoxyphenyl group, and a camphor group which may have one or more substituents.
In the general formula (1), R 4 is such as, for example, an alkyl group having 1 to 5 carbon atoms such as a methyl group and an ethyl group, and a hydrogen atom.
Among these, from the viewpoint of obtaining a high catalytic activity, R 4 is preferably a methyl group or a hydrogen atom, more preferably a hydrogen atom.
In the general formula (1), Ar is such as, for example, an unsubstituted benzene, a benzene having an alkyl group, and a cyclopentadienyl group which may have one or more substituents.
The benzene having an alkyl group is such as, for example, toluene, o—, m— and p-xylene, o—, m—and p-cymene, 1,2,3-, 1,2,4-, and 1,3,5-trimethylbenzene, 1,2,4,5-tetramethylbenzene, 1,2,3,4-tetramethylbenzene, pentamethylbenzene, and hexamethylbenzene.
The cyclopentadienyl group which may have one or more substituents is such as, for example, a cyclopentadienyl group, methylcyclopentadienyl group, 1,2-dimethylcyclopentadienyl group, 1,3-dimethylcyclopentadienyl group, 1,2,3-trimethylcyclopentadienyl group, 1,2,4-trimethylcyclopentadienyl group, 1,2,3,4-tetramethylcyclopentadienyl group and 1,2,3,4,5-pentamethylcyclopentadienyl group.
Among these, from the viewpoint of giving a high asymmetric yield and the availability of the ingredient materials, Ar is preferably a p-cymene, 1,3,5-trimethylbenzene, 1,2,4,5-tetramethylbenzene, hexamethylbenzene or 1,2,3,4,5-pentamethylcyclopentadiene, and more preferably a p-cymene, 1,3,5-trimethylbenzene or 1,2,3,4,5-pentamethylcyclopentadiene.
In the general formula (1), X is, for example an anionic group, and an anionic group herein includes a halogen atom.
The anionic group is such as, for example, fluorine atom, chlorine atom, bromine atom, iodine atom, tetrafluoroborate group, tetrahydroborate group, tetrakis[3,5-bis(trifluoromethyl)phenyl]borate group, acetoxy group, benzoyloxy group, (2,6-dihydroxybenzoyl)oxy group, (2,5-dihydroxybenzoyl)oxy group, (3-aminobenzoyl)oxy group, (2,6-dimethoxybenzoyl)oxy group, (2,4,6-triisopropylbenzoyl)oxy group, 1-naphthalene carboxylic acid group, 2-naphthalene carboxylic acid group, trifluoroacetoxy group, trifluoromethanesulfoxy group and trifluoromethanesulfonimide group.
Among these, from the viewpoint of the availability of the ingredient materials, an anionic group is preferably a chlorine atom, bromine atom, iodine atom or trifluoromethanesulfoxy group, more preferably a chlorine atom or trifluoromethanesulfoxy group.
In the general formula (1), M is such as, for example, ruthenium, rhodium and iridium.
Among these, in view of the cost, M is preferably ruthenium or iridium.
The metal complex represented by the general formula (1) has a structure in which a bidentate ligand, ethylenediamine derivative or cyclohexanediamine derivative, (a ligand of the general formula (1): R 3 SO 2 NHCHR 1 CHR 2 NHR 4 ) is coordinated to ruthenium, rhodium or iridium. Because the structure of the ligand that gives a high reactivity or asymmetric yield varies depending on the structure of the substrate, an optimum ethylenediamine derivative or cyclohexanediamine derivative may be selected in accordance with the structure of the substrate.
The ethylenediamine derivative is, though not particularly limited, such as, for example, TsDPEN(N-(p-toluenesulfonyl)-1,2-diphenyl ethylenediamine), MsDPEN (N-methanesulfonyl-1,2-diphenyl ethylenediamine), N-(benzylsulfonyl)-1,2-diphenyl ethylenediamine, N-(cyclohexanesulfonyl)-1,2-diphenyl ethylenediamine, N-(2,5-dimethylbenzylsulfonyl)-1,2-diphenyl ethylenediamine, N-(iso-butylsulfonyl)-1,2-diphenyl ethylenediamine, N-methyl-N′-(p-toluenesulfonyl)-1,2-diphenyl ethylenediamine, N-(p-methoxyphenylsulfonyl)-1,2-diphenyl ethylenediamine, N-(p-chlorophenylsulfonyl)-1,2-diphenyl ethylenediamine, N-trifluoromethanesulfonyl-1,2-diphenyl ethylenediamine, N-(2,4,6-trimethylbenzenesulfonyl)-1,2-diphenyl ethylenediamine, N-(2,4,6-triisopropylbenzenesulfonyl)-1,2-diphenyl ethylenediamine, N-(4-tert-butylbenzenesulfonyl)-1,2-diphenyl ethylenediamine, N-(2-naphthylsulfonyl)-1,2-diphenyl ethylenediamine, N-(3,5-dimethylbenzenesulfonyl)-1,2-diphenyl ethylenediamine, N-pentamethylbenzenesulfonyl-1,2-diphenyl ethylenediamine, N-(10-camphorsulfonyl)-1,2-diphenyl ethylenediamine, N-(benzylsulfonyl)-1,2-ethanediamine and N-(sec-butylsulfonyl)-1,2-ethanediamine.
These ethylenediamine derivatives are selected according to the structure of the ketone substrate. They are preferably, from the viewpoint of the general use, TsDPEN and MsDPEN, and from the viewpoint of obtaining a relatively high asymmetric yield in reactions of various ketones, ethylenediamine derivatives, such as N-(benzylsulfonyl)-1,2-diphenylethylenediamine, N-(cyclohexanesulfonyl)-1,2-diphenylethylenediamine, N-(2,5-dimethylbenzylsulfonyl)-1,2-diphenylethylenediamine, and N-(iso-butylsulfonyl)-1,2-diphenylethylenediamine.
The cyclohexanediamine derivative is, though not particularly limited, such as, for example, TsCYDN(N-(p-toluenesulfonyl)-1,2-cyclohexanediamine), MsCYDN (N-(p-methanesulfonyl)-1,2-cyclohexanediamine), N-(benzylsulfonyl)-1,2-cyclohexanediamine, N-(cyclohexanesulfonyl)-1,2-cyclohexanediamine, N-(cyclohexanesulfonyl)-1,2-cyclohexanediamine, N-(2,5-dimethylbenzylsulfonyl)-1,2-cyclohexanediamine, N-(iso-butylsulfonyl)-1,2-cyclohexanediamine, N-methyl-N′-(p-toluenesulfonyl)-1,2-cyclohexanediamine, N-(p-methoxyphenylsulfonyl)-1,2-cyclohexanediamine, N-(p-chlorophenylsulfonyl)-1,2-cyclohexanediamine, N-trifluoromethanesulfonyl-1,2-cyclohexanediamine, N-(2,4,6-trimethylbenzenesulfonyl)-1,2-cyclohexanediamine, N-(2,4,6-triisopropylbenzenesulfonyl)-1,2-cyclohexanediamine, N-(4-tert-butylbenzenesulfonyl)-1,2-cyclohexanediamine, N-(2-naphthylsulfonyl)-1,2-cyclohexanediamine, N-(3,5-dimethylbenzenesulfonyl)-1,2-cyclohexanediamine, N-pentamethylbenzenesulfonyl-1,2-cyclohexanediamine, N-(p-toluenesulfonyl)-1,2-cyclohexanediamine, and N-(10-camphorsulfonyl)-1,2-cyclohexanediamine.
These cyclohexanediamine derivatives are selected according to the structure of the ketone substrate. They are preferably, from the viewpoint of the general use, TsCYDN and MsCYDN, and from the viewpoint of obtaining a relatively high asymmetric yield in reactions of various ketones, ethylenediamine derivatives, such as N-(benzylsulfonyl)-1,2-cyclohexanediamine, N-(iso-butylsulfonyl)-1,2-cyclohexanesulfonyl)-1,2-cyclohexanediamine, and N-(2,5-dimethylbenzylsulfonyl)-1,2-cyclohexanediamine are preferred.
The ruthenium compound that is used as a starting material of the ruthenium complex represented by the general formula (1) is such as, for example, an inorganic ruthenium compound such as ruthenium (III) chloride hydrate, ruthenium (III) bromide hydrate and ruthenium (III) iodide hydrate; a ruthenium complex in which a diene is coordinated such as [ruthenium dichloride (norbornadiene)] poly-nuclear complex, [ruthenium dichloride (cycloocta-1,5-diene)] poly-nuclear complex and bis(methylallyl) ruthenium (cycloocta-1,5-diene); a ruthenium complex in which an aromatic compound is coordinated such as [ruthenium dichloride (benzene)] poly-nuclear complex, [ruthenium dichloride (p-cymene)] poly-nuclear complex, [ruthenium dichloride (trimethylbenzene)] poly-nuclear complex and [ruthenium dichloride (hexamethylbenzene)] poly-nuclear complex; a ruthenium complex in which a phosphine is coordinated such as dichlorotris(triphenylphosphine) ruthenium, as well as ruthenium dichloride (dimethylformamide) 4 , and chlorohydride tris(triphenylphosphine) ruthenium.
In addition, a ruthenium complex is not particularly limited to the above as long as it has a ligand that is capable of being substituted with an optically active diphosphine compound or optically active diamine compound. For example, various ruthenium complexes described in COMPREHENSIVE ORGANOMETALLIC CHEMISTRY II Vol. 7 p 294-296 (PERGAMON) may be used as a starting material.
Similarly, a rhodium compound that can be used as a starting material for the rhodium complex represented by the general formula (I) is, for example, an inorganic rhodium compound such as rhodium (III) chloride hydrate, rhodium (III) bromide hydrate and rhodium (III) iodide hydrate, as well as [pentamethylcyclopentadienyl rhodium dichloride] poly-nuclear complex, [pentamethylcyclopentadienyl rhodium dibromide] poly-nuclear complex and [pentamethylcyclopentadienyl rhodium diiodide] poly-nuclear complex. An iridium compound that can be used as a starting material for the iridium complex represented by the general formula (I) is, for example, an inorgaganic iridium compound such as iridium (III) chloride hydrate, iridium (III) bromide hydrate and iridium (III) iodide hydrate, as well as [pentamethylcyclopentadienyl iridium dichloride] poly-nuclear complex, [pentamethyl cyclopentadienyl iridium dibromide] poly-nuclear complex and [pentamethyl cyclopentadienyl iridium diiodide] poly-nuclear complex.
The reaction of the stating material ruthenium, rhodium or iridium compounds with the ligand is performed in one or more solvents selected from the group consisting of aromatic hydrocarbon solvents such as toluene and xylene, aliphatic hydrocarbon solvents such as pentane and hexane, halogen-containing hydrocarbon solvents such as methylene chloride, ether solvents such as diethyl ether and tetrahydrofuran, alcoholic solvents such as methanol, ethanol, 2-propanol, butanol and benzylalcohol, and organic solvents containing heteroatoms such as acetonitrile, DMF (dimethylformamide), N-methylpyrrolidone and DMSO (dimethylsulfoxide), at a reaction temperature between 0° C. to 200° C. A metal complex which is an asymmetric catalyst to be used in the method according to the invention, can be obtained by the above reaction.
In order to obtain an optically active alcohol it is necessary that the two asymmetric carbons in the metal complex represented by the general formula (1) used as an asymmetric catalyst in the method according to the invention are either both (R) enantiomers or both (S) enantiomers. Selecting either of these (R) enantiomer and (S) enantiomer enables a high selectivity for the optically active alcohol of desired absolute configuration. These metal complexes may be used alone or in combination of two or more.
The amount of the metal complex used in the method according to the invention represented by the general formula (1) may be in the range from 10 to 20,000 S/C, as expressed by the molar ratio of the ketone substrate to that of the metal complex, i.e., S/C (wherein S indicates the substrate and C indicates the catalyst). Within this range, from the viewpoint of reaction efficiency and economic efficiency, it is preferably in the range from 100 to 10,000, more preferably in the range from 1,000 to 10,000.
The solvent(s) used in the method according to the invenntion that is capable of resolving the asymmetric catalyst and formate salt is not limited to its type, as long as the solvent(s) is capable of resolving the metal complex, i.e., an asymmetric catalyst, and the formate salt, and is, for example, organic solvents such as a protic solvent(s), an organic acid and an ionic liquid except polyethylene glycol, and a mixed solvent of water and an water-miscible aprotic solvent(s). The organic solvent(s) may further comprise water and an water-miscible aprotic solvent(s).
The protic solvent(s) is(are) such as aliphatic alcohols, multivalent alcohols and organic acids, among which a protic solvent(s) having 1 to 5 carbon atoms is(are) preferred. These protic solvents may also be used alone or in a combination of two or more.
The aliphatic alcohol is such as, for example, methanol, ethanol, 2-propanol, n-propyl alcohol, 2-methyl-2-propanol and 2-methyl-2-butanol. Among these, from the viewpoint of high reactivity due to high solubility of the formate salt, preferred is an alcohol having 1 to 5 carbon atoms, and more preferred is methanol or ethanol, and most preferred is methanol.
The polyalcohol is such as, for example, ethylene glycol, glycerin and propylene glycol.
The organic acid is such as, formic acid, acetic acid, propionic acid and trifluoroacetic acid.
The ionic liquid is, such as, an ionic liquid comprising an imidazolium as a cation such as 1-ethyl-3-methylimidazolium bromide, 1-ethyl-3-methylimidazolium hexafluorophosphate and 1-butyl-3-methylimidazolium trifluoromethane sulfonate, an ionic liquid comprising a pyridinium as a cation such as 1-ethylpyridinium bromide and 1-hexylpyridinium tetrafluoroborate, an ionic liquid comprising a quaternary ammonium as a cation such as N,N,N-trimethyl-N-propylammonium bis(trifluoromethane sulfonyl)imide, and an ionic liquid comprising phosphonium as a cation such as (1-naphthyl)triphenylphosphonium chloride.
The water-miscible aprotic solvent(s) is(are) not limited to its type, as long as it is(they are) a solvent(s) miscible with water and capable of resolving the metal complex, i.e., the asymmetric catalyst, and the formate salt, and is such as, for example, DMF (dimethylformamide), DMSO (dimethylsulfoxide), THF (tetrahydrofuran), 1,4-dioxane, acetonitrile and pyridine. These aprotic solvents may be used alone or in combination of two or more.
The ketone substrate used in the method according to the invention is such as, for example, a cyclic ketone, a ketone having an olefin moiety, a ketone having an acetylene moiety, a ketone having a hydroxyl group, a ketone having a halogen atom, a diketone, a ketoester and a ketoamide, which may have one or more substituents having a it (pi) electron, for example an aromatic ring, a heteroaromatic ring, a carbon-carbon triple bond, a carbon-carbon double bond, nearby the carbonyl group, or other substituents including a carboxylic acid group, an ester group, a carboxylic amide group, a carbonyl group, an amino group, an amide group, a cyano group, a nitro group, a chlorine group, a bromine group, an iodine group, a trifluoromethyl group, a hydroxyl group, an alkoxy group, a thiol group, a trimethylsilyl group, a tert-butyldimethylsilyl group, and other substituents comprising heteroatoms.
The process for producing an optically active alcohol described in the present invention is effective for the reaction of ketone substrates having various substituents. There is no need for particularly limiting the structure of a ketone substrate, though it is such as, for example, as an aromatic ketone, acetophenone, propiophenone, 3′-chloroacetophenone, 2′-trifluoromethylacetophenone, 3′,5′-bis(trifluoromethyl)acetophenone and 3′-hydroxyacetophenone. A cyclic ketone is such as 4-chromanone, 1-indanone and 1-tetralone. A ketone having other functional groups is phenacyl chloride, α-hydroxyacetophenone, benzoin, α-nitroacetophenone, α-cyanoacetophenone, α-azideacetophenone, α-(methoxycarbonyl)acetophenone, α-(ethoxycarbonyl)acetophenone, 1-(tert-butyldimethylsilyl)-1-butyn-3-one and 1-(trimethylsilyl)-1-butyn-3-one.
The formate salt used as a hydrogen source to supply hydrogen atoms to a ketone substrate is such as, for example, a salt of formic acid and an alkali metal or an alkali earth metal, which may be used alone or in combination of two or more.
The salt of formic acid and an alkali metal or an alkali earth metal is such as, for example, lithium formate, sodium formate, potassium formate, cesium formate, magnasium formate and calcium formate. Among these, from the viewpoint of a high reactivity, a salt of formic acid and an alkali metal or an alkali earth metal is preferably potassium formate or sodium formate, more preferably potassium formate.
Furthermore, in the method according to the inventino, an acid or base may be added as required. An acid to be added is, though not particularly limited, for example, organic acids such as formic acid and acetic acid. A base is inorganic basic compounds such as potassium hydroxide, sodium hydroxide, potassium carbonate, sodium carbonate, potassium hydrogencarbonate and sodium hydrogencarbonate, or organic basic compounds such as triethylamine and DBU. These acids and bases may be used alone or in combination of two or more, and the mixture thereof may be used for the asymmetric reduction reaction of a ketone substrate.
The reaction temperature is, though not particularly limited, in view of the economic efficiency, preferably in the range from 0 to 70° C., more preferably from 20 to 60° C.
The reaction time varies depending on the reaction conditions such as the types, concentration or S/C of the reacting substrates or temperature, or the type of the catalyst. Therefore, the various conditions may be determined so as to allow the reaction to be finished in several minutes to several days, preferably, in particular, in 5 to 24 hours.
The purification method of the reaction product, i.e., optically active alcohol, is not particularly limited. For instance, a known method such as column chromatography, distillation and recrystallization may be employed.
The asymmetric reduction reaction of the ketone substrate in the process of the present invention may also be performed in a reaction type of either a batch type or continuous type.
EXAMPLES
The followings describe the working examples and comparative examples of the present invention to illustrate the present invention in more detail, though the present invention is not limited by these working examples.
In the working examples below, the solvent(s) used for the reactions was(were) purchased reagents. The identification of the product was performed by nuclear magnetic resonance (NMR) spectroscopy using JNM-LA400 (400 MHz, JEOL Ltd.). Tetramethylsilane (TMS) was used as an internal standard substance for the measurement by 1 HNMR, and its signal was determined as δ=0 (6 is a chemical shift). The optical purity was measured by gas chromatography (GC) or high-performance liquid chromatography (HPLC). Chirasil-DEX CB (0.25 mm×25 m, DF=0.25 μm) (CHROMPACK, Inc.) was used for GC, and CHIRALCEL OD (0.46 cm×25 cm), CHIRALCEL OJ (0.46 cm×25 cm), CHIRALCEL OB-H (0.46 cm×25 cm) and CHIRALCEL OJ-H (0.46 cm×25 cm) (DAICEL CHEMICAL INDUSTRIES, LTD.) were used for HPLC.
Working Example 1
A ruthenium complex RuCl[(R,R)-Tsdpen] (p-cymene) (6.4 mg, 0.01 mmol), potassium formate (1.0 g, 12 mmol) and 4-chromanone (1.48 g, 10 mmol, substrate/catalyst ratio=1,000) were set in a 20 mL glass Schlenk-type reaction tube under an argon atmosphere. Methanol (6 mL) was added thereto and stirred at 50° C. After reacting for 3 hours, the yield of (R)-4-chromanol was 99%, and the optical purity was 99% ee. The reaction was allowed to further continue to give, after 6 hours, a yield of 100% and optical purity of 99% ee. After 24 hours, (R)-4-chromanol was produced at 100% yield and 99% ee optical purity.
This confirmed that the racemization of (R)-4-chromanol did not proceed over time in this reaction system.
Comparative Example 1
A ruthenium complex RuCl[(R,R)-Tsdpen] (p-cymene) (6.4 mg, 0.01 mmol), TBAB (tetrabutylammonium bromide) (32.2 mg, 0.1 mmol), potassium formate (1.0 g, 12 mmol) and 4-chromanone (1.48 g, 10 mmol, substrate/catalyst ratio=1,000) were set in a 20 mL glass Schlenk-type reaction tube under an argon atmosphere. Water (2 mL) and toluene (2 mL) were added thereto and stirred at 50° C. After reacting for 3 hours, the yield of the product (R)-4-chromanol was 90%, and the optical purity was 92% ee. The reaction was allowed to further continue to give, after 6 hours, a yield of 99% and optical purity of 92% ee. After 24 hours, (R)-4-chromanol was produced at 99% yield and 90% ee optical purity.
This confirmed that the racemization of (R)-4-chromanol proceeded over time in the two-phase reduction reaction system.
Comparative Example 2
Argon was introduced into a 20 mL Schlenk-type reaction tube and bathed in an ice bath, then triethyl amine (3.6 mL, 26 mmol), formic acid (1.2 mL, 31 mmol), 4-chromanone (1.48 g, 10 mmol, substrate/catalyst ratio=500) and ruthenium complex RuCl[(R,R)-Tsdpen] (p-cymene) (12.7 mg, 0.02 mmol) were set therein, stirred at 30° C. for 24 hours. On its course, samples were collected after 3 hours for 1 HNMR and HPLC analyses of the product. The conversion rate after 3 hours was 66%, and the optical purity was 99% ee. The reaction was allowed to further continue, and after 24 hours, (R)-4-chromanol was produced at 100% yield of and 99% ee optical purity.
This confirmed that the reaction efficiency was low, though the racemization of (R)-4-chromanol did not proceed over time in the formic acid reaction system.
Working Examples 2-7
The reaction was performed to synthesize (R)-4-chromanol under similar conditions to those of Working Example 1 at 50° C. and for 24 hours, except changing the solvent(s) and the types of the hydrogen source, i.e., formate salt. The results are summarized in Table 1.
TABLE 1
Working
Formate
Yield
Optical purity
Example
Solvent(s)
salt
(%)
(% ee)
2
4 mL methanol
—
potassium
100
98.6
2 mL water
formate
3
4 mL methanol
—
sodium
100
98.8
2 mL water
formate
4
5 mL methanol
DMF
potassium
100
99.1
1 mL
formate
5
6 mL methanol
—
potassium
100
98.4
2 mL water
formate
6
2 mL water
DMSO
potassium
100
97.8
5 mL
formate
7
2 mL water
DMF
potassium
100
97.8
5 mL
formate
Working Examples 8-13
The reaction was performed to synthesize (R)-4-chromanol under a similar conditions to those of Working Example 1 at 50° C. and for 24 hours, except using RuCl[(R,R)-Tsdpen] (p-cymene) to perform the reaction at a higher S/C, or changing the catalyst to be used. The results are summarized in Table 2. Note that, in Working Example 9, the reaction solvent was a mixed solvent of 4 mL methanol and 2 mL water.
TABLE 2
Working
Optical purity
Example
S/C
Catalyst
Yield (%)
(% ee)
8
5000
RuCl[(R,R)-
86
99.2
Tsdpen](p-cymene)
1.3 mg (0.002 mmol)
9
5000
RuCl[(R,R)-
95
98.6
Tsdpen](p-cymene)
1.3 mg (0.002 mmol)
10
1000
Ru(OTf)[(R,R)-
100
95.9
Tscydn](p-cymene)
6.5 mg (0.01 mmol)
11
1000
Ru(OTf) [(R)-Cs-(R,R)-
100
99.5
dpen](mesitylene)
7.9 mg (0.01 mmol)
12
1000
Cp*Ir(OTf)[(S,S)-
100
99.7
Msdpen]
7.6 mg (0.01 mmol)
13
1000
Cp*RhCl[(S,S)-
100
99.9
Msdpen]
5.6 mg (0.01 mmol)
Working Example 14
A ruthenium complex RuCl[(R,R)-Tsdpen] (p-cymene) (6.4 mg, 0.01 mmol), potassium formate (1.0 g, 12 mmol) and acetophenone (1.20 g, 10 mmol, substrate/catalyst ratio=1000) were set in a 20 mL glass Schlenk-type reaction tube under an argon atmosphere. Methanol (6 mL) was added thereto and stirred at 50° C. for 24 hours to give (R)-1-phenylethanol at 100% yield and 96.2% ee optical purity.
Working Examples 15-20
The reaction was performed to synthesize each optically active alcohol under a similar condition to those of Working Example 14 except changing the ketone substrate. The results are summarized in Table 3. Note that, in Working Example 15, the reaction temperature was set at 30° C., and, in Working Example 19, the reaction was performed for 16 hours.
TABLE 3
Working
Optical purity
Example
R
Yield (%)
(% ee)
15
CH 2 Cl
99
97.8
1.55 g (10 mmol)
16
CH 2 OH
100
94.6
1.36 g (10 mmol)
17
CH 2 CN
91
95.4
1.45 g (10 mmol)
18
CH(OH)Ph
74
100
2.12 g (10 mmol)
19
CH 2 CO 2 CH 3
100
96.5
1.78 g (10 mmol)
20
(CH 2 ) 2 OH
59
93.4
1.52 g (10 mmol)
Working Example 21
A ruthenium complex RuCl[(R,R)-Tsdpen] (mesitylene) (2.1 mg, 0.0033 mmol), potassium formate (1.0 g, 12 mmol), formic acid (138 mg, 3 mmol) and 3′-chloroacetophenone (1.55 g, 10 mmol, substrate/catalyst ratio=3000) were set in a 20 mL glass Schlenk-type reaction tube under an argon atmosphere. Methanol (6 mL) was added thereto and stirred at 50° C. for 24 hours to give (R)-1-(3′-chlorophenyl)ethanol at 100% yield and 96.5% ee optical purity.
Working Example 22
A ruthenium complex RuCl[(S,S)-BnSO 2 dpen] (mesitylene) (1.2 mg, 0.002 mmol), potassium formate (1.0 g, 12 mmol), formic acid (138 mg, 3 mmol) and 3′-chloroacetophenone (1.55 g, 10 mmol, substrate/catalyst ratio=5000) were set in a 20 mL glass Schlenk-type reaction tube under an argon atmosphere. Methanol (6 mL) was added thereto and stirred at 50° C. for 24 hours to give (S)-1-(3′-chlorophenyl)ethanol at 85% yield and 96.5% ee optical purity.
Working Example 23
A ruthenium complex Ru(OTf)[(S,S)-iso-BuSO 2 dpen] (p-cymene) (1.4 mg, 0.002 mmol), potassium formate (1.0 g, 12 mmol), and 3′,5′-bis(trifluoromethyl)acetophenone (2.56 g, 10 mmol, substrate/catalyst ratio=5000) were set in a 20 mL glass Schlenk-type reaction tube under an argon atmosphere. Methanol (6 mL) was added thereto and stirred at 50° C. for 24 hours to give (S)-1-[3′,5′-bis(trifluoromethyl)phenyl]ethanol at 100% yield and 87.7% ee optical purity.
Accordingly, the effect of the present invention is that it suppresses the racemization of the product while maintaining the high reactivity of the two-phase reaction system to give an optically active alcohol at a high optical purity. | The object of the present invention is to solve the problems in the prior arts, and to find more improved reaction conditions for suppressing the racemization of the product and obtaining an optically active alcohol at a high optical purity. The inventors achieved to solve the above problems by using a solvent system that is capable of resolving both an asymmetric catalyst and a formate salt, allowing the hydrogen source and the asymmetric catalyst to be present in the same phase. | 2 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to bumpers for doors and fenders for vehicles and more particularly pertains to a new vehicle door and fender protection assembly for preventing vehicle doors and fenders from being nicked, scratched, and dented.
2. Description of the Prior Art
The use of bumpers for doors and fenders for vehicles is known in the prior art. More specifically, bumpers for doors and fenders for vehicles heretofore devised and utilized are known to consist basically of familiar, expected and obvious structural configurations, notwithstanding the myriad of designs encompassed by the crowded prior art which have been developed for the fulfillment of countless objectives and requirements.
Known prior art includes U.S. Pat. Nos. 4,708,380; 5,129,695; 5,956,918; 5,112,092; 5,149,166; and U.S. Pat. No. Des. 308,848.
While these devices fulfill their respective, particular objectives and requirements, the aforementioned patents do not disclose a new vehicle door and fender protection assembly. The inventive device includes padded members being adapted to attach to doors and fenders of a vehicle; and also includes shell members being adapted to cover the padded members; and further includes a vehicle attachment assembly for attaching the padded members and the shell members to the vehicle.
In these respects, the vehicle door and fender protection assembly according to the present invention substantially departs from the conventional concepts and designs of the prior art, and in so doing provides an apparatus primarily developed for the purpose of preventing vehicle doors and fenders from being nicked, scratched, and dented.
SUMMARY OF THE INVENTION
In view of the foregoing disadvantages inherent in the known types of bumpers for doors and fenders for vehicles now present in the prior art, the present invention provides a new vehicle door and fender protection assembly construction wherein the same can be utilized for preventing vehicle doors and fenders from being nicked, scratched, and dented.
The general purpose of the present invention, which will be described subsequently in greater detail, is to provide a new vehicle door and fender protection assembly apparatus and method which has many of the advantages of the bumpers for doors and fenders for vehicles mentioned heretofore and many novel features that result in a new vehicle door and fender protection assembly which is not anticipated, rendered obvious, suggested, or even implied by any of the prior art bumpers for doors and fender s for vehicles, either alone or in any combination thereof.
To attain this, the present invention generally comprises padded members being adapted to attach to doors and fenders of a vehicle; and also includes shell members being adapted to cover the padded members; and further includes a vehicle attachment assembly for attaching the padded members and the shell members to the vehicle.
There has thus been outlined, rather broadly, the more important features of the invention in order that the detailed description thereof that follows may be better understood, and in order that the present contribution to the art may be better appreciated. There are additional features of the invention that will be described hereinafter and which will form the subject matter of the claims appended hereto.
In this respect, before explaining at least one embodiment of the invention in detail, it is to be understood that the invention is not limited in its application to the details of construction and to the arrangements of the components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments and of being practiced and carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein are for the purpose of description and should not be regarded as limiting.
As such, those skilled in the art will appreciate that the conception, upon which this disclosure is based, may readily be utilized as a basis for the designing of other structures, methods and systems for carrying out the several purposes of the present invention. It is important, therefore, that the claims be regarded as including such equivalent constructions insofar as they do not depart from the spirit and scope of the present invention.
Further, the purpose of the foregoing abstract is to enable the U.S. Patent and Trademark Office and the public generally, and especially the scientists, engineers and practitioners in the art who are not familiar with patent or legal terms or phraseology, to determine quickly from a cursory inspection the nature and essence of the technical disclosure of the application. The abstract is neither intended to define the invention of the application, which is measured by the claims, nor is it intended to be limiting as to the scope of the invention in any way.
It is therefore an object of the present invention to provide a new vehicle door and fender protection assembly apparatus and method which has many of the advantages of the bumpers for doors and fenders for vehicles mentioned heretofore and many novel features that result in a new vehicle door and fender protection assembly which is not anticipated, rendered obvious, suggested, or even implied by any of the prior art bumpers for doors and fenders for vehicles, either alone or in any combination thereof.
It is another object of the present invention to provide a new vehicle door and fender protection assembly which may be easily and efficiently manufactured and marketed.
It is a further object of the present invention to provide a new vehicle door and fender protection assembly which is of a durable and reliable construction.
An even further object of the present invention is to provide a new vehicle door and fender protection assembly which is susceptible of a low cost of manufacture with regard to both materials and labor, and which accordingly is then susceptible of low prices of sale to the consuming public, thereby making such vehicle door and fender protection assembly economically available to the buying public.
Still yet another object of the present invention is to provide a new vehicle door and fender protection assembly which provides in the apparatuses and methods of the prior art some of the advantages thereof, while simultaneously overcoming some of the disadvantages normally associated therewith.
Still another object of the present invention is to provide a new vehicle door and fender protection assembly for preventing vehicle doors and fenders from being nicked, scratched, and dented.
Yet another object of the present invention is to provide a new vehicle door and fender protection assembly which includes padded members being adapted to attach to doors and fenders of a vehicle and also includes shell members being adapted to cover the padded members; and further includes a vehicle attachment assembly for attaching the padded members and the shell members to the vehicle.
Still yet another object of the present invention is to provide a new vehicle door and fender protection assembly that intercepts objects such as doors of other vehicles and carts from damaging the doors and fenders of one's vehicle.
Even still another object of the present invention is to provide a new vehicle door and fender protection assembly that can be easily and quickly attached to the doors and fenders of one's vehicle.
These together with other objects of the invention, along with the various features of novelty which characterize the invention, are pointed out with particularity in the claims annexed to and forming a part of this disclosure. For a better understanding of the invention, its operating advantages and the specific objects attained by its uses, reference should be made to the accompanying drawings and descriptive matter in which there are illustrated preferred embodiments of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will be better understood and objects other than those set forth above will become apparent when consideration is given to the following detailed description thereof. Such description makes reference to the annexed drawings wherein:
FIG. 1 is a perspective view of a new vehicle door and fender protection assembly according to the present invention and shown mounted to a vehicle.
FIG. 2 is a top plan view of the present invention mounted to a vehicle.
FIG. 3 is a cross-sectional view of the present invention.
FIG. 4 is a perspective view of a belt of the present invention.
FIG. 5 is a side elevational view of the belt of the present invention mounted to a vehicle.
FIG. 6 is a side elevational view of a second embodiment of the present invention.
FIG. 7 is perspective view of a third embodiment of the present invention.
FIG. 8 is an exploded perspective view of the present invention.
FIG. 9 is another side elevational view of the present invention mounted to a vehicle.
FIG. 10 are side elevational views of different embodiments of fender padded members of the present invention.
FIG. 11 is a schematic sectional view of the fender padded member and fender shell member taken along line 11 — 11 of FIG. 10 .
DESCRIPTION OF THE PREFERRED EMBODIMENT
With reference now to the drawings, and in particular to FIGS. 1 through 11 thereof, a new vehicle door and fender protection assembly embodying the principles and concepts of the present invention and generally designated by the reference numeral 10 will be described.
As best illustrated in FIGS. 1 through 11, the vehicle door and fender protection assembly 10 generally comprises padded members 11 , 12 being adapted to attach to doors 30 and fenders 31 of a vehicle 29 . The padded members 11 , 12 include door padded members 11 and fender padded members 12 which have ends which are removably attached to ends of the door padded members 11 . Shell members 14 , 15 are adapted to conventionally cover the padded members 11 , 12 . The shell members 14 , 15 include door shell members 14 and fender shell members 15 which are removably attached to ends of the door shell members 14 . The padded members 11 , 12 and the shell members 14 , 15 are contoured and adapted to the shapes of the doors 30 and fenders 31 of the vehicle 29 . Each of the padded members 11 , 12 and the shell members 14 , 15 are tapered toward an end thereof.
A vehicle attachment assembly for attaching the padded members 11 , 12 and the shell members 14 , 15 to the vehicle 29 includes, as a first embodiment, length-adjustable elastic belts 16 each having fastening members 17 , 18 securely and conventionally attached at ends thereof and being detachably connected to one another, and also includes hook and loop fasteners 20 being conventionally disposed upon and along outer sides 19 of the length-adjustable elastic belts 16 . The length-adjustable elastic belts 16 are adapted to fasten about doors 30 of a vehicle 29 with the hook and loop fasteners 20 being conventionally disposed on an outside of the vehicle 29 and facing away from the vehicle 29 . The padded members 11 , 12 are attachable to the hook and loop fasteners 20 . The vehicle attachment assembly also includes strips of hook and loop fasteners 24 having a ridged spine 34 and being conventionally attached along edges of the ends of the door padded members 11 and the fender padded members 12 to substantially secure the fender padded members 12 to the door padded members 12 . Each of the length-adjustable elastic belts 16 includes a notch 22 being disposed in a bottom edge 21 thereof near one of the fastening members 17 , 18 and being adapted to receive a portion of the door 30 , and also includes a rigid sleeve 23 being conventionally disposed thereupon near one of the fastening members 17 , 18 . The vehicle attachment assembly also includes an elastic strap 25 having a hook member 26 securely and conventionally disposed at one end and a loop member 27 being securely and conventionally disposed at another end. The hook member 26 is adapted to hook about an edge of a door 30 . The loop member 27 is adapted to receive one of the length-adjustable elastic belts 16 therethrough. The elastic strap 25 further having hook and loop fasteners 20 being securely and conventionally disposed upon and along an outer side thereof and being adapted to fasten to one of the door padded members 11 .
As a second embodiment, the vehicle attachment assembly includes a plurality of suction cup members 28 being spaced about and being securely and conventionally attached to back sides 13 of the padded members 11 , 12 for attaching the padded members 11 , 12 to the doors 30 and fenders 31 of the vehicle 29 . The vehicle attachment assembly further includes anti-theft strap members 33 being spaced apart and being attached to the padded members 11 , 12 .
As a third embodiment, the vehicle attachment assembly includes a magnetic sheet 32 being attached to the padded members 11 as shown in FIG. 8 and being attachable to the vehicle 29 .
In use, the user fastens the elastic belts 16 horizontally about the doors 30 of the vehicle 29 and attaches the padded members 11 , 12 to the elastic belts 16 to protect the doors 30 and fenders 31 of the vehicle 29 .
As to a further discussion of the manner of usage and operation of the present invention, the same should be apparent from the above description. Accordingly, no further discussion relating to the manner of usage and operation will be provided.
With respect to the above description then, it is to be realized that the optimum dimensional relationships for the parts of the invention, to include variations in size, materials, shape, form, function and manner of operation, assembly and use, are deemed readily apparent and obvious to one skilled in the art, and all equivalent relationships to those illustrated in the drawings and described in the specification are intended to be encompassed by the present invention.
Therefore, the foregoing is considered as illustrative only of the principles of the invention. Further, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described, and accordingly, all suitable modifications and equivalents may be resorted to, falling within the scope of the invention. | A vehicle door and fender protection assembly for preventing vehicle doors and fenders from being nicked, scratched, and dented. The vehicle door and fender protection assembly includes padded members being adapted to attach to doors and fenders of a vehicle; and also includes shell members being adapted to cover the padded members; and further includes a vehicle attachment assembly for attaching the padded members and the shell members to the vehicle. | 8 |
BACKGROUND
The invention relates generally to providing an apparatus for electrochemical removal of metal on products made from metals. More particularly, the invention relates to an apparatus for the electrochemical treatment of medical devices made of titanium, stainless steel, tungsten, nickel-titanium, tantalum, cobalt-chromium-tungsten, cobalt-chromium, and the like to form a more hemodynamically compatible device.
While a wide range of products or devices can be made from the listed metal alloys for use with the present invention, medical devices are particularly suitable due to the biocompatible characteristics of these alloys. Thus, for example, implantable medical devices or devices that are used within the human body are particularly suitable and can be made from these alloys that have been electrochemically treated in accordance with the present invention. More particularly, and as described in more detail herein, intravascular stents can be made from the listed alloys that have been electrochemically treated according to the invention. Thus, while the description of prior art devices and of the invention herein refers mainly to intravascular stents, the invention is not so limited to medical products or intravascular stents.
Stents are generally metallic tube shaped intravascular devices which are placed within a blood vessel to structurally hold open the vessel. The device can be used to maintain the patency of a blood vessel immediately after intravascular treatments and can be used to reduce the likelihood of development of restenosis. Expandable stents are frequently used as they may travel in compressed form to the stenotic site generally either crimped onto an inflation balloon or compressed into a containment sheath in a known manner.
Metal stents can be formed in a variety of expandable configurations such as helically wound wire stents, wire mesh stents, weaved wire stents, metallic serpentine stents, or in the form of a chain of corrugated rings. Expandable stents, such as wire mesh, serpentine, and corrugated ring designs, for example, do not possess uniformly solid tubular walls. Although generally cylindrical in overall shape, the walls of such stents are perforated often in a framework design of wire-like elements or struts connected together or in a weave design of cross threaded wire.
Expandable stents formed from metal offer a number of advantages and are widely used. Metallic serpentine stents, for example, not only provide strength and rigidity once implanted they also are designed sufficiently compressible and flexible for traveling through the tortuous pathways of the vessel route prior to arrival at the stenotic site. Additionally, metallic stents may be radiopaque, thus easily visible by radiation illumination techniques such as x-ray film.
It is highly desirable for the surface of the stent to be extremely smooth so that it can be inserted easily and experience low-friction travel through the tortuous vessel pathway prior to implantation. A roughened outer surface may result in increased frictional obstruction during insertion and excess drag during travel to the stenotic site as well as damaging the endothelium lining of the vessel wall. A rough surface may cause frictional resistence to such an extent as to prevent travel to desired distal locations. A rough finish may also cause damage to the underlying inflation balloon. A less rough finish decreases thrombogenicity and increases corrosion resistance.
Stents have been formed from various metals including stainless steel, tantalum, titanium, tungsten, nickel-titanium which is commonly called Nitinol, and alloys formed with cobalt and chromium. Stainless steel has been extensively used to form stents and has often been the material of choice for stent construction. Stainless steel is corrosion resistant, strong, yet may be cut into very thin-walled stent patterns.
Cobalt-chromium alloy is a metal that has proven advantages when used in stent applications. Stents made from a cobalt-chromium alloy may be thinner and lighter in weight than stents made from other metallic materials, including stainless steel. Cobalt-chromium alloy is also a denser metal than stainless steel. Additionally, cobalt-chromium stents are nontranslucent to certain electromagnetic radiation waves, such as X-rays, and, relative to stainless steel stents, provide a higher degree of radiopacity, thus being easier to identify in the body under fluoroscopy.
Metal stents, however, suffer from a number of disadvantages. They often require processing to eliminate undesirable burrs, nicks, or sharp ends. Expandable metal stents are frequently formed by use of a laser to cut a framework design from a tube of metal. The tubular stent wall is formed into a lattice arrangement consisting of metal struts with gaps therebetween. Laser cutting, however, typically is at high temperature and often leaves debris and slag material attached to the stent. Such material, if left on a stent, would render the stent unacceptable for implantation. Treatment to remove the slag, burrs, and nicks is therefore required to provide a device suitable for use in a body lumen.
Descaling is a first treatment of the surface in preparation for further surface treatment such as electropolishing. Descaling may include, for example, scraping the stent with a diamond file, followed by dipping the stent in a hydrochloric acid or an HCl mixture, and thereafter cleaning the stent ultrasonically. A successfully descaled metal stent should be substantially slag-free in preparation for subsequent electropolishing
Further finishing is often accomplished by the well known technique of electropolishing. Grinding, vibration, and tumbling techniques are often not suited to be employed on small detailed parts such as stents.
Electropolishing is an electrochemical process by which surface metal is dissolved. Sometimes referred to as “reverse plating,” the electropolishing process actually removes metal from the surface desired to be smoothed. The metal stent is connected to a power supply (the anode) and is immersed in a liquid electrolytic solution along with a metal cathode connected to the negative terminal of the power supply. Current is applied and flows from the stent, causing it to become polarized. The applied current controls the rate at which the metal ions of the anodic stent are generally removed and diffused through the solution to the cathode.
The rate of the electrochemical reaction is proportional to the current density. The positioning and thickness of the cathode in relation to the stent is important to make available an even distribution of current to the desired portion of the stent sought to be smoothed. For example, some prior art devices have a cathode in the form of a flat plate or a triangular or single wire loop configuration, which may not yield a stent or other medical device with a smooth surface on all exposed surfaces. For example, the prior art devices do not always provide a stent having a smooth surface on the inner tubular wall of the stent where blood flow will pass.
What is needed is an apparatus and a process for treating a product or device made of a metal alloy to remove metal from the product to create a more streamlined shape to enhance hemodynamic flow. The present invention satisfies this need.
SUMMARY OF THE INVENTION
The invention is directed to an improved apparatus and method for the electrochemical treatment of an intravascular stent formed from a metal alloy. The invention is directed to an apparatus and method for electrochemically treating the struts of an intravascular stent in order to remove a portion of the stent struts to form an airfoil shape. More particularly, the cross-section of one more struts of the stent have a shape that resembles an airfoil or a hydrofoil which will reduce turbulent blood flow in the vasculature in which the stent is implanted, thereby improving clinical outcome. In one embodiment, an electrical fixture holds a stent within an electrolitic bath. Preferably, the stent is held stationary within the electrical fixture while an electrolyte is flowed through the inner lumen of the stent. The stent is energized by subjecting it to a direct voltage or by applying a voltage to the fixture that contacts the stent. These contacts can be made by leads that are in electrical communication with a power source. A cathode is positioned within the stent to create an electrical current directed toward the inner lumen and inner diameter of the stent. When the stent is energized with a different electrical potential than that of the cathode, the material of the stent will begin to dissolve into the electrolyte. The electrolyte is constantly flowing through the inner lumen of the stent and as the metallic material of the stent dissolves, it will be swept out of the stent inner lumen by the flow of electrolytic.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 an elevational view, partially in section, of a stent of the present invention mounted on a rapid exchange delivery catheter and positioned within an artery.
FIG. 2 is an elevational view, partially in section, similar to that in FIG. 1 , wherein the stent is expanded within the artery, so that the stent embeds partially within the arterial wall.
FIG. 3 is an elevational view, partially in section, showing the expanded stent implanted within the artery after withdrawal of the rapid exchange delivery catheter.
FIG. 4 is a cross-sectional view of a prior art stent in which the stent struts have a rectangular cross-section thereby causing turbulent flow of blood through the artery.
FIG. 5 is a plan view of a flattened stent of one embodiment of the invention which illustrates a pattern of rings and links.
FIG. 6 is a partial plan view of the stent of FIG. 5 which has been expanded to approximately 4.0 mm inside diameter.
FIG. 7 is a cross-sectional view taken along lines 7 - 7 depicting a rectangular cross-section of a stent strut of FIG. 6 .
FIG. 8 is an elevational view, partially in section, of an assembly for pumping an electrolytic solution through the inner diameter of the stent to remove metal from the stent struts.
FIG. 9 is an end view of the assembly of FIG. 8 .
FIGS. 10A-10D are a series of cross-sectional views of a single strut of the stent of the invention as electrolytic solution passes over the stent and progressively removes metal from the stent strut.
FIG. 11 is a transverse cross-sectional view of an airfoil-shaped stent strut partially imbedded in an artery wall.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The present invention stent improves on existing stents by providing a longitudinally flexible stent having a uniquely designed pattern and novel interconnecting members. In addition to providing longitudinal flexibility, the stent of the present invention also provides radial rigidity and a high degree of scaffolding of a vessel wall, such as a coronary artery. The design of the highly flexible interconnecting members and their placement relative to an adjacent U-shaped member provides for a tightly compressed stent onto a catheter while maintaining a high degree of flexibility during delivery.
Turning to the drawings, FIG. 1 depicts a prior art stent 10 mounted on a conventional catheter assembly 12 which is used to deliver the stent and implant it in a body lumen, such as a coronary artery, peripheral artery, or other vessel or lumen within the body. The catheter assembly includes a catheter shaft 13 which has a proximal end 14 and a distal end 16 . The catheter assembly is configured to advance through the patient's vascular system by advancing over a guide wire by any of the well known methods of an over the wire system (not shown) or a well known rapid exchange catheter system, such as the one shown in FIG. 1 .
Catheter assembly 12 as depicted in FIG. 1 is of the well known rapid exchange type which includes an RX port 20 where the guide wire 18 will exit the catheter. The distal end of the guide wire 18 exits the catheter distal end 16 so that the catheter advances along the guide wire on a section of the catheter between the RX port 20 and the catheter distal end 16 . As is known in the art, the guide wire lumen which receives the guide wire is sized for receiving various diameter guide wires to suit a particular application. The stent is mounted on the expandable member 22 (balloon) and is crimped tightly thereon so that the stent and expandable member present a low profile diameter for delivery through the arteries.
As shown in FIG. 1 , a partial cross-section of an artery 24 is shown with a small amount of plaque that has been previously treated by an angioplasty or other repair procedure. Stent 10 is used to repair a diseased or damaged arterial wall which may include the plaque 26 as shown in FIG. 1 , or a dissection, or a flap which are sometimes found in the coronary arteries, peripheral arteries and other vessels.
In a typical procedure to implant stent 10 , the guide wire 18 is advanced through the patient's vascular system by well known methods so that the distal end of the guide wire is advanced past the plaque or diseased area 26 . Prior to implanting the stent, the cardiologist may wish to perform an angioplasty procedure or other procedure (i.e., atherectomy) in order to open the vessel and remodel the diseased area. Thereafter, the stent delivery catheter assembly 12 is advanced over the guide wire so that the stent is positioned in the target area. The expandable member or balloon 22 is inflated by well known means so that it expands radially outwardly and in turn expands the stent radially outwardly until the stent is apposed to the vessel wall. The expandable member is then deflated and the catheter withdrawn from the patient's vascular system. The guide wire typically is left in the lumen for post-dilatation procedures, if any, and subsequently is withdrawn from the patient's vascular system. As depicted in FIGS. 2 and 3 , the balloon is fully inflated with the stent expanded and pressed against the vessel wall, and in FIG. 3 , the implanted stent remains in the vessel after the balloon has been deflated and the catheter assembly and guide wire have been withdrawn from the patient.
The stent 10 serves to hold open the artery after the catheter is withdrawn, as illustrated by FIG. 3 . Due to the formation of the stent from an elongated tubular member, the undulating components of the stent are relatively flat in transverse cross-section. When the stent is expanded, it is pressed into the wall of the artery, however, portions of the rectangular cross-section may protrude into the artery lumen and may interfere with the blood flow through the artery. The stent is pressed into the wall of the artery and will eventually be covered with endothelial cell growth which will minimize blood flow interference. The undulating portion of the stent provides good tacking characteristics to prevent stent movement within the artery. Furthermore, the closely spaced cylindrical elements at regular intervals provide uniform support for the wall of the artery.
Referring to FIG. 4 , a portion of an artery 24 is shown in cross-section with a typical prior art stent at least partially embedded in the artery wall. The stent is comprised of rectangular-shaped stent struts 27 that have an inner surface 28 that faces the blood flow. In FIG. 4 , the blood is flowing from left to right in the artery. Because of the rectangular-shaped stent struts 27 having a vertical surface impeding blood flow, there is some turbulent blood flow in and around the stent struts as shown by the diagrammatic arrows in FIG. 4 . These localized areas of turbulent blood flow produce adverse vascular reactions such as the proliferation of restenosis and the formation of plaque 26 . Typically, the rectangular-shaped stent struts 27 will have rounded corners due to electropolishing, however, even though the corners have been rounded there is still turbulent blood flow that may produce the adverse vascular reactions.
Referring to FIG. 5 , stent 30 is shown in a flattened condition so that the pattern can be clearly viewed, even though the stent is in a cylindrical form in use. The stent is typically formed from a tubular member.
As shown in FIGS. 5-6 , stent 30 is made up of a plurality of cylindrical rings 40 which extend circumferentially around the stent when it is in a tubular form (see FIG. 3 ). Each cylindrical ring 40 has a cylindrical ring proximal end 46 and a cylindrical ring distal end 48 . Typically, since the stent is laser cut from a tube there are no discreet parts such as the described cylindrical rings and links. However, it is beneficial for identification and reference to various parts to refer to the cylindrical rings and links and other parts of the stent as follows.
Each cylindrical ring 40 defines a cylindrical plane 50 which is a plane defined by the proximal and distal ends 46 , 48 of the ring and the circumferential extent as the cylindrical ring travels around the cylinder. Each cylindrical ring includes cylindrical outer wall surface 52 which defines the outermost surface of the stent, and cylindrical inner wall surface 53 which defines the innermost surface of the stent. Cylindrical plane 50 follows the cylindrical outer wall surface.
An undulating link 54 is positioned within cylindrical plane 50 . The undulating links connect one cylindrical ring 40 to an adjacent cylindrical ring 40 and contribute to the overall longitudinal flexibility to the stent due to their unique construction. The flexibility of the undulating links derives in part from curved portion 56 connected to straight portions 58 wherein the straight portions are substantially perpendicular to the longitudinal axis of the stent. Thus, as the stent is being delivered through a tortuous vessel, such as a coronary artery, the curved portions 56 and straight portions 58 of the undulating links will permit the stent to flex in the longitudinal direction which substantially enhances delivery of the stent to the target site. The number of bends and straight portions in a link can be increased or decreased from that shown, to achieve differing flexibility constructions. With the straight portions being substantially perpendicular to the stent longitudinal axis, the undulating link acts much like a hinge at the curved portion to provide flexibility. A straight link that is parallel to the stent axis typically is not flexible and does not add to the flexibility of the stent.
Referring to FIGS. 5-6 , the stent 30 can be described more particularly as having a plurality of first peaks 60 , second peaks 61 , and valleys 62 . Although the stent is not divided into separate elements, for ease of discussion references to peaks and valleys is appropriate. The number of peaks and valleys can vary in number for each ring depending upon the application. Thus, for example, if the stent is to be implanted in a coronary artery, a lesser number of peaks and valleys are required than if the stent is implanted in a peripheral artery, which has a larger diameter than a coronary artery. As can be seen for example in FIG. 6 , peaks 60 , 61 are in phase 63 , meaning that the peaks 60 , 61 point in the same direction and are substantially aligned along the longitudinal axis of the stent. It may be desirable under certain circumstances to position the peaks so that they are out of phase (not shown), that is, the peaks of one ring would be circumferentially offset from the peaks of an adjacent ring so that the apex of adjacent peaks pointed toward each other. As shown in FIGS. 5-6 , the peaks are circumferentially offset 64 from the valleys and from the undulating link 54 . Positioning the peaks, valleys, and undulating links in this manner, provides a stent having uniform expansion capabilities, high radial strength, a high degree of flexibility, and sufficient wall coverage to support the vessel.
As shown in FIG. 7 , a rectangular-shaped stent strut 80 is shown in a transverse cross-sectional configuration from one of the peaks 69 from FIG. 6 . More specifically, during a typical laser cutting of a thin metallic tube, the resulting transverse cross-sectional shape of all of the stent struts are generally a rectangular-shaped stent strut 80 like that shown in FIG. 7 . Further processing including electropolishing will remove the sharp corners so that the basic overall rectangular shape remains, only with rounded corners so as to have a less invasive impact on the arterial wall when the stent is delivered and implanted. As previously described with respect to the rectangular-shaped stent struts in FIGS. 4 and 7 , such a cross-sectional shape likely will result in turbulent blood flow and the adverse affects resulting therefrom. While FIG. 7 illustrates a rectangular-shaped stent strut, other cross-sectional configurations will benefit from the present invention as well. Thus, for example, a square cross-section, or any other cross-section having a leading edge that will disrupt blood flow, will benefit from the present invention.
As shown in FIGS. 8-10D , the stent of the present invention is placed in a chamber in which electrolytic solution flows through an inner lumen of the stent in order to remove metal from the stent struts and shape certain of the struts into an airfoil or hydrofoil shape. More specifically, those stent struts that are substantially perpendicular to the longitudinal axis of the stent and thereby the flow of the electrolytic solution, will be formed into a cross-sectional shape of a hydrofoil, in which the leading edge of the strut is thicker than the trailing end of the strut. When in use, as blood flows along the strut surface, it will maintain a laminar flow without disturbing the adjacent vasculature as much as if the stent strut were rectangular shaped thereby causing turbulent blood flow. While the stent struts of the present invention may not be a perfect airfoil shape or hydrofoil shape where the trailing edge would be relatively sharp, the trailing edge thickness is reduced compared to the leading edge thickness, but still has sufficient thickness to provide radial strength to hold the stent open and to avoid mechanically scoring or otherwise damaging the tissue of the vessel wall.
In keeping with the invention, as shown in FIGS. 8-11A , a chamber 82 has a longitudinal bore 84 extending therethrough and is configured for receiving a stent 30 . The diameter of the longitudinal bore is configured to be slightly greater than the outer diameter of the stent 30 so that the stent 30 can be placed in the longitudinal bore without pushing on or having an interference fit that may damage the stent struts. The chamber 82 optionally has an end cap (not shown) that can be secured to the chamber by any conventional means such as screw threads (not shown) or a ratcheting lock, both of which are known in the art. A longitudinal axis 88 extends through the longitudinal bore 84 of the chamber. The chamber has a first end 90 and a second end 92 defining the overall length of the chamber, which can vary depending upon the length of the stent that is inserted therein.
As shown in FIG. 8 , the stent 30 is mounted or inserted into the longitudinal bore 84 and the outer diameter of the stent is just slightly less than the diameter of the longitudinal bore 84 . In this embodiment, the stent 30 is held in place in the longitudinal bore by a flange or ridge 94 which will ensure that the stent does not move longitudinally as the electrolytic solution flows past the stent and removes metal. In this embodiment, a second longitudinal bore 96 is formed near the second end 92 of the chamber 82 wherein the second longitudinal bore has a diameter that is less than the outer diameter of the stent and less than the diameter of the longitudinal bore 84 in order to form the flange 94 .
The longitudinal bore 84 has a diameter that is greater than the outer diameter of the stent 30 . It is intended that different sized chamber 82 having different diameter longitudinal bores 84 be used for stents having different outer diameters. For example, a typical coronary artery stent in the manufactured configuration can have an outer diameter from between 2 mm to 3.5 mm, and have a length between 8 mm and 30 mm. More typically, a coronary stent has an outer diameter of about 3 mm and length of about 20 mm. The longitudinal bore 84 has a diameter that is greater than the outer diameter of the stent so that the stent can be easily inserted into the chamber 82 and into longitudinal bore 84 without scraping or damaging the stent struts. After the stent is inserted into the longitudinal bore 84 , the optional end cap is secured to the chamber 82 so that the end cap abuts one end of the stent 30 , but does not force the stent against the flange 94 or ridge which is at the opposite end of the longitudinal bore from the end cap. Thus, after the end cap is secured to the chamber, the stent should have substantially no longitudinal movement within the longitudinal bore 84 , and just have a slight amount of clearance between the diameter of the longitudinal bore and the outer diameter of the stent. The end cap will have a lumen or bore to allow the flow of electrolytic solution into the chamber.
With further reference to FIGS. 8 and 9 , the stent 30 is positioned inside the longitudinal bore 84 so that an electrolytic solution 100 can flow over the stent and dissolve metal from the stent by a process known as electrolytic machining. Electrolytic machining involves the application of an electrical current to the workpiece, in this case the stent 30 , while flowing an electrolytic solution over the stent surface. The stent acts as an anode and is dissolved into the electrolytic solution toward the cathode of the system. The rate at which metal is dissolved from the surface of the stent struts will vary depending on the velocity of the electrolyte at any surface location on the stent struts. This is due to the speed at which material can be swept away from the surface of the stent struts. In the embodiment shown in FIGS. 8 and 9 , the stent is the anode (+) 120 and a wire 122 that extends through the longitudinal bore 84 is a cathode 124 . A power source 126 provides a current that flows from the anode 120 , thereby polarizing the anode, and encouraging metal ions on the surface of the stent to diffuse through the electrolytic solution 100 toward the cathode 122 . The composition of the electrolytic solution 100 is well known in the art and can vary depending upon the type of metal used to form the stent. The current density is greatest at the high points on the inner surface of the stent and lowest at lower points on the stent which are the outer surface of the stent. The rate of the electrochemical reaction is directly proportional to the density and the flow rate of the electrolytic solution so that increased current density at the raised points causes the anodic metal to dissolve faster at these points as metal dissolves from the surface of the stent. Further factors that affect the rate at which metal is removed from the stent struts are the current density, the duration of the applied current, the flow rate of the electrolytic solution 100 , and the temperature of the electrolytic solution.
The wire 122 forming the cathode 124 can typically be formed of numerous configurations such as 90% platinum and 10% iridium clad over a niobium core. Other types of wires for use as cathodes are well known in the art.
One of the factors that determines the amount of metal and the rate of removal of metal from the stent struts is the flow rate of the electrolytic solution 100 . In one embodiment, the flow rate of the electrolytic solution 100 is in the range of 0.2 mL per second to 50.0 mL per second. These flow rates are by way of example only, and can be varied depending upon numerous factors including the type of metal from which the stent is formed, the size of the stent, and the transverse cross-sectional shapes of the stent struts. The pump used to pump the electrolytic solution through the chamber 82 is not shown, and is well known in the art.
In further keeping with the invention, and referring to FIGS. 10A-10D , an electrolytic solution 100 flows over the stent struts 102 of stent 30 . The electrolytic solution 100 enters the chamber 82 (through a lumen or bore in the end cap) and flows through the longitudinal bore 84 of the chamber. As can be seen in FIGS. 10A-10D , as the electrolytic solution flows over the stent struts 102 , which typically have a rectangular cross-section as shown in FIG. 7 , the first edge 106 of the stent strut becomes rounded and metal is removed from the first edge at a greater rate than at the second edge 108 . In other words, the first edge 106 of the stent strut 102 is directly in the flow of the electrolytic solution 100 and metal will dissolve from the first edge at a rate faster than metal being dissolved from the second edge 108 on the downstream side of the electrolytic solution. As the electrolytic solution 100 travels over the stent strut 102 , it dissolves less metal from second edge 108 since that edge is not directly in line with the flow of electrolytic solution. Thus, the second edge 108 will have a thickness that is greater than the thickness of first edge 106 , and both the first edge and the second edge will be curved, thereby taking the shape of an airfoil or hydrofoil. It is noted that first edge 106 does not have so much metal removed that it resembles a knife edge, like a typical airfoil or hydrofoil, but some metal is removed so that the first edge 106 has less thickness than the second edge 108 , yet the stent strut 102 still has enough cross-sectional area so as to not compromise the structural integrity of the stent. In other words, after processing with the electrolytic solution 100 , the stent 30 still will have the structural integrity to hold open a vessel, such as a coronary artery, yet will have the benefit of the stent struts having an airfoil shaped cross-section in order to reduce turbulent blood flow.
More specifically, the strut radial thickness of stent 30 for a coronary artery stent typically is about 0.0032 inch. It will be appreciated, however, that the strut radial thickness can be thicker or thinner, depending on the stent design and where it is implanted. Thus, the strut radial thickness can be in the range from 0.060 inch to 0.002 inch. The present invention reduction in radial thickness of the struts can range from about 5% to about 20% at the first edge 106 and from about 3% to about 15% at the second edge 108 . Preferably, the radial thickness of the first edge 106 is reduced by 20% and radial thickness of the second edge is reduced by 5%. As an example, for a stent strut that has a radial thickness of 0.0032 inch, the first edge 106 will be 20% thinner, or about 0.0026 inch and the second edge 108 will be 5% thinner, or about 0.003 inch. Further, the strut surface extending between the first edge 106 and second edge 108 may be straight or slightly curved and essentially form a taper, gradually getting thicker going from the first edge toward the second edge.
Referring to FIGS. 8-10D , it will be appreciated that those stent struts 102 that will benefit the most from the use of the electrolytic solution 100 in chamber 82 are those stent struts that are perpendicular to the flow of the electrolytic solution. Thus, for example, referring to FIG. 6 , peak 69 and straight portions 58 are stent struts that are substantially perpendicular to the longitudinal axis of the stent and thus are perpendicular to the flow of the electrolytic solution 100 . It is expected that these stent struts will have a cross-sectional shape that resembles an airfoil or hydrofoil as previously discussed. Those stent struts that are not substantially perpendicular to the direction of the flow of the electrolytic solution 100 , also benefit from the present invention in that the transverse cross-section may not have a perfect airfoil-shaped cross-section, however, the first edge 106 of such stent struts will generally have more metal removed than the second edge 108 of such stent struts.
The stent 30 of the present invention can be mounted on a balloon catheter similar to that shown in FIG. 1 . The stent is tightly compressed or crimped onto the balloon portion of the catheter and remains tightly crimped onto the balloon during delivery through the patient's vascular system. When the balloon is expanded, the stent expands radially outwardly into contact with the body lumen, for example, a coronary artery. When the balloon portion of the catheter is deflated, the catheter system is withdrawn from the patient and the stent remains implanted in the artery. Similarly, if the stent of the present invention is made from a self-expanding metal alloy, such as nickel-titanium or the like, the stent may be compressed or crimped onto a catheter and a sheath (not shown) is placed over the stent to hold it in place until the stent is ready to be implanted in the patient. Such sheaths are well known in the art. Further, such a self-expanding stent may be compressed or crimped to a delivery diameter and placed within a catheter. Once the stent has been positioned within the artery, it is pushed out of the catheter or the catheter is withdrawn proximally and the stent held in place until it exits the catheter and self-expands into contact with the wall of the artery. Balloon catheters and catheters for delivering self-expanding stents are well known in the art.
It is important to note that the airfoil shape of the stent strut 102 as shown for example in FIG. 10D , has a second edge 108 that is thicker than a first edge 106 . When the stent 30 is implanted in a vessel, such as a coronary artery 24 shown in FIG. 11 , it is more likely that blood in the artery will flow from the second edge 108 toward the first edge 106 much like the airflow over the airfoil of an airplane wing. In other words, the leading edge (second edge 108 ) of the stent strut 102 is thicker than the trailing edge (first edge 106 ), and as blood flows along the strut surface as shown by arrow A, it maintains a laminer flow without disturbing the adjacent vasculature as much as if the stent strut were more rectangular-shaped. Further, the present invention using electrolytic machining may also form a stent strut that has a tapered shape rather than an airfoil shape, and still be beneficial in the reduction of blood flow turbulence.
Electrolytic machining processing can be performed by companies such as Kennemetal Extrude Hone, Grand Rapids, Mich.
While the invention has been illustrated and described herein, in terms of its use as an intravascular stent, it will be apparent to those skilled in the art that the stent can be used in other body lumens. Other modifications and improvements may be made without departing from the scope of the invention. | An apparatus and method for electrochemically treating the struts of an intravascular stent is disclosed. An intravascular stent is mounted in a chamber and is electrochemically treated in order to remove a portion of the stent struts in order to form an airfoil shape. The airfoil-shaped stent struts will reduce turbulent blood flow in the vasculature in which the stent is implanted thereby improving clinical outcome. | 2 |
PRIORITY STATEMENT
[0001] This application claims the benefit of U.S. Provisional Application 61/335,258 filed Jan. 4, 2010.
FIELD OF THE INVENTION
[0002] The present invention relates to vent tubes incorporating one or more detectors or indicators for use in conjunction with a filling machine during container filling operations to increase the safety of the filling operation and reduce the associated cost and time when a malfunction occurs. In particular, the present invention relates to food or beverage vent tubes incorporating a Radio Frequency Identification (RFID) tag and can incorporate other types of tags or traceable material allowing for a quicker and more accurate detection of an intrusion (and the location) of a food or beverage vent tube that has become detached from a filling machine during filling operations.
BACKGROUND OF THE INVENTION
[0003] In the food and beverage industry there is a need for efficient and reliable manufacturing processes to quickly and safely manufacture and package the food and beverage product. Most food and beverage plants across the United States run continuously, 24 hours a day and 7 days a week, to meet the ever increasing demands. With these stringent demands on their machines as well as personnel, most food and beverage plants have implemented some form of process control or automation. By using programmable logic controllers (PLCs) and various other logic controlling devices, elementary applications that used to require manual attention can now be done with machines.
[0004] In particular, the demand today for beverage containers filled with product, such as cola and beer, is greater than it has ever been and continues to grow. These containers can be glass bottles, aluminum cans or any type of canister that can store, for example, consumable beverages, automobile product, hair and skin care product, and any other liquid or semi-liquid product that is packaged and distributed in such a container. These container packages can be any size and shape, such as those found in 12 ounce cola or beer cans and bottles, and the various bottles containing hair care product. These containers can be made from many different materials, such as glass, plastic, aluminum, tin among others, and are enclosed, after being filled with product, using a type of cap or top attached by screwing onto the container, crimping, pressing or heat sealing, or in other ways to enclose the product in the container.
[0005] In order to meet this demand for liquid and semi-liquid product, high speed, automatic filling machines are incorporated in the filling process. These automatic machines can load, fill, enclose, and box up thousands of these containers each minute in a high-speed operation. These automatic filling machines load the empty containers onto a conveyor and move the bottles into a location on the machines where the containers come in contact with the filling machine and are filled with product. Once filled, the containers are enclosed or sealed and are quickly moved away from the filling station, and boxed up or packaged along with other filled containers to be shipped or distributed to retail centers and the like.
[0006] In such a high-speed operation, when an accident or mistake occurs, hundreds or thousands of containers may inadvertently be filled before the filling machine or process can be halted. In these situations, the hundreds or thousands of containers filled after the accident may need to be discarded, wasting time and money to determine which bottles were filled after the accident.
[0007] The fill process will vary depending on the product being filled, and various factors, such as the temperature and viscosity of the product, the beverage gas, the effect of those gases and related pressure characteristics during the filling process. Accordingly, the filling process and related conditions can be optimized and maximized monitoring and controlling these factors. For purposes of this application and for simplicity, most of the examples herein will refer to a carbonated beverage filling process, although the apparatus, system and methods described herein relate to any similar type of filling process.
[0008] Further, the filling process can not alter the food or beverage being filled. Thus, when planning a filling system it is important to match the appropriate filling steps to the beverage characteristics and container. The steps of the filling process include some or all of the following: evacuation of the container, flushing the container with gas, pressurizing the container with gas, filling the container with one or multiple speeds, fill level correction (in certain cases), and settling the product.
[0009] Evacuation is used mostly on rigid containers in which a vacuum process removes upwards of 90% of the air content in the container prior to pressurizing with gas. Evacuation becomes more important when the contents being filled are oxygen sensitive and the may be repeated at other times throughout the filling process. Additionally or alternatively, the container may be flushed with gas. This is done mostly with flexible containers, such as PET bottles and aluminum cans, which may not be able to withstand a vacuum. The flushing step takes place at the time that the fill valve is located at the container and usually uses gas from the filling ring bowl until both pressures are the same.
[0010] Next, filling takes place when the fill valve opens and the product flows over and around the vent tube and into the container. As the container fills, gas in the containers is displaced by the product and flows through the vent tube and out of the container into the filler ring bowl, until the container is full. As an example, the vent tube may contain an electronic probe to detect product and stop filling. Accordingly, the vent tube vents the gases being used while filling the container with fluid. The process needs to be extremely accurate, and as a result most vent tubes are designed at specific lengths to achieve each specific fill level per filling machine.
[0011] Fill level correction may be incorporated when the cost of product is high to save product. In the most commonly used fill level correction step, the container is first overfilled with product and then the product is extracted using a vacuum through the vent tube. Finally, by settling, the pressure in the container is lowered and the beverage is allowed to settle as it is lowered from the fill valve.
[0012] The vent tubes used in the filling process described above usually are configured with an elongated, hollow, cylindrical tube extending the length of the tube which allows the vent tube to enter the container opening during the fill process without touching the container. As described above and in U.S. Pat. No. 3,736,966, which is incorporated by reference herein, the product can flow over the vent tube into the container. The lower tip of the vent tube is usually closed and one or more holes are provided so that any gas or air in the container can be displaced through the vent tube during the filling process, minimizing or eliminating the possibility of a container exploding during filling
[0013] Traditionally, filling machines for glass containers use a vent tube made of stainless steel or a stainless food-grade plastic hybrid. For filling aluminum containers, the vent tube is usually made from some form of food-grade plastic, such as Delrin®. Vent tubes can also use a ball and cage system as described in U.S. Publication No. US20050199314 A1, which is incorporated by reference herein.
[0014] Due to the high speeds and constant use of these filling machines, occasionally a vent tube may detach from the filling machine and fall into the product container. When this event occurs there are minimal systems in place to halt the filling process, locate the detached vent tube, repair the filling machine and begin the process again. Each minute that the process is halted equates to thousands of unfilled containers, as filling machines can run at speeds of 1650 cans per minute. Further, the longer the process continues, the more filled containers that will have to be examined to find the detached vent tube. In many situations, the containers filled with product that were boxed up or packaged after the vent tube became detached are merely discarded, increasing the costs of the accident.
[0015] Some of the current systems used to check for detached stainless steel vent tubes include the use of inductive or capacitive sensors, vision systems or other ultrasonic inline systems. Additionally, systems for determining when a vent tube has become detached and fallen into the container include the electromagnetic detection fields or X-ray based technologies. Some of the manufactures of these technologies include Omron Corporation, Industrial Dynamics Company, and the Fortress Technology Inc, among others.
[0016] However, most of these inspection systems need to have direct access to each and every container after it has been filled with product, and are used as a way to detect the vent tube by examining each container. This process either slows down the filling line because each and every container must be examined, or takes longer time than necessary to find the container in which the vent tube has fallen if each container has not been examined.
[0017] Further, some of the systems work better with metal vent tubes, while other systems work better with plastic vent tubes creating inconsistencies, or the need for additional equipment when changing to different vent tubes. For example, when a plastic vent tube falls into a can made of aluminum at a filling plant, the inductive and capacitive technologies cannot detect the plastic vent tube (foreign) object through the aluminum can.
[0018] There is currently no apparatus, system or method that incorporates an indicator, such as an RFID tag, into a vent tube for use during filling operations, that increases the safety of the filling operation and reduces the costs and time when a malfunction occurs, such as when a vent tube detaches from the filling machine and falls into the container. There is also no apparatus, system or method relating to vent tubes incorporating an RFID tag that allows for a quicker and more accurate determination of the location of a vent tube that has become detached from a filling machine during filling operations. The present invention satisfies these needs.
SUMMARY OF THE INVENTION
[0019] In order to solve the above-mentioned shortcomings in filling operations, the present invention utilizes apparatus, system and/or methods for determining the location of a vent tube when it malfunctions and becomes detached from a filling machine and, in special cases, falls or intrudes into a container being filled. In particular, the invention utilizes a vent tube modified with a traceable material, such as an RFID tag, and can incorporate a system and methods for scanning a filling machine, as well as food or beverage containers, using sensing technologies, such as RFID technology.
[0020] The present invention solves the problems facing the packaging industry, and in particular, the beverage filling industry as described above. The present invention incorporates a solution for consistent detection of vent tube intrusion into a container, which exceeds the current standards at specific beverage manufacturing plants.
[0021] At large automated beverage manufacturing plants, aluminum cans are a commonly used container for product. As described above, when a plastic vent tube falls into aluminum can as it is being filled, the inductive and capacitive technologies normally used to detect metal vent tube, cannot detect the plastic foreign object through the aluminum can. As a result expensive X-ray systems used or product is considered waste.
[0022] The present invention solves this inherent problem by incorporating or implementing an RFID tag into each vent tube and associated monitoring systems. The incorporated RFID tag can be used on metal, metal-plastic hybrid, ball cage, and plastic vent tubes with the same result. By placing an in-line identification gate or RFID scanner or reader after the filling process occurs, and a continuous monitoring system on the filling machine any such vent tube can be reliably tracked if it becomes detached from the filling machine during the filling process.
[0023] By tagging the vent tube with an RFID transponder or other tagging technologies, routine consistency checks will not have to be performed. Further, other materials may now be considered as containers for the packaging side of the manufacturing facilities.
[0024] The vent tube detection system used in conjunction with the present invention has several components, such as chips, tags, readers and antennas. By incorporating an RFID tag or transponder or other tagging technology into the vent tube, the vent tube can be tracked using the same transponder or tag reading system as described above. Since the transponder is created by attaching a small silicon chip to a small flexible antenna, the chip can be used to record and store information. To read the transponder and locate the specific vent tube, the RFID reader sends out a radio signal to be absorbed by the antenna and reflected back as a return signal delivering information from the transponder chip memory.
[0025] In use, the container filling machine operates in its normal manner with empty containers sent down a conveyor to the filling section of the system. The vent tube is then lowered (or the empty container is raised) to come in contact or near contact with the container. The container is filled with the product as described above, and the vent tube is separated from the filled container. The filled container is then covered and/or sealed. This filling process fills thousands of containers each minute.
[0026] If, during these high-speed operations, a vent tube malfunctions (i.e., detaches or sheers from the filling machine, and falls into the container), the RFID transponder incorporated into the vent tube will likewise fall into the filled container. Using the vent tube detection system, the system can have immediate information that the vent tube has detached from the filling system and precisely which container the vent tube is located. The reader can be anywhere from 1 foot to 20 to 30 feet from the location of the container or filling machine depending on the type of RFID tag used. Further, handheld RFID tag readers can be used at the time of the malfunction to assist in finding the broken vent tube.
[0027] The vent tube detection system can be set up at various locations in the filling plant in order to make sure that a vent tube has not been accidentally been misplaced into a filled container before the container is shipped out of the plant.
[0028] These and other aspects, features, and advantages of the present invention will become more readily apparent from the attached drawings and the detailed description of the preferred embodiments, which follow.
DRAWINGS
[0029] The preferred embodiments of the invention will be described in conjunction with the appended drawings provided to illustrate and not to the limit the invention, where like designations denote like elements, and in which:
[0030] FIG. 1 illustrates a filling machine in accordance with one embodiment of the present invention;
[0031] FIG. 2 illustrates an inspection system for inspecting empty and full containers in accordance with the present invention;
[0032] FIGS. 3A and 3B illustrate a vent tube incorporating indicators in accordance with an embodiment of the present invention; and
[0033] FIG. 4 illustrates an exemplary indicator detection system in accordance with an embodiment of the present invention.
DETAILED DESCRIPTION
[0034] As described herein, product, such as cola or beer, is transferred from the production, brewing or fabrication stage to the packaging stage to be individually packaged for sale. This transfer process is known as the fill or filling process and utilizes automatic high-speed filling equipment to fill and seal thousands of containers each minute. Often, these automatic filling machines are of the rotary filler type, which may vary in size from 40, 60, 72, 100, 120 or 180 fill valves and vent tubes per machine, allowing for the filling of thousands of containers each minute that the machine is in use.
[0035] FIG. 1 shows a typical rotary bottle or can filler 10 , such as one manufactured by KHS AG, which incorporates vent tubes 12 in the filling (and venting) process. In general terms and as described in more detail herein, a vent tube 12 come in contact or near contact with a container 14 prior to filling the container 14 with the product (not shown). Once a container 14 is in the correct position, product can be transferred to the container 14 with air or gas in the container displaced through the vent tube 12 . The container is then sealed or seamed (not shown).
[0036] For glass containers 14 , the vent tube 12 is usually made of stainless steel, but can be made of a food grade plastic, stainless steel hybrid. For aluminum containers, the vent tube 12 is usually made of a food grade plastic material. In a ball cage vent tube, a food grade plastic ball is used to start and stop the flow of gas.
[0037] Due to the high speeds where thousands and tens of thousands of containers are filled each minute, and due to the constant use of these filling machines 10 , occasionally a vent tube 12 may detach from the filling machine 10 and fall into the product container 14 . If and when this event occurs there are a few primitive systems in place to locate the vent tube 12 and halt the filling process before thousands of additional containers are filled, making it more difficult to locate the container 14 with the broken vent tube 12 .
[0038] FIG. 2 shows a typical container inspection machine 20 , such as from the manufacturer Industrial Dymnamics/filtec, in which each filled container must pass before each container can be packaged and distributed. As described herein, these inspection machines 20 utilize various technologies to sense imperfections in the filling process, including when a foreign material, such as a vent tube, falls into a container. The technologies include using inductive and capacitive sensors, vision systems or other ultrasonic inline systems. However, in most of these systems, each container must be individually scanned or tested. For example, the vision system utilizes a light shined through each container (assuming glass or some other translucent material) and a video/vision camera that compares the viewed filled container against a table for any discrepancies. These systems generally slow down the filling process, are expensive and do not always detect a vent tube 12 that has inadvertently detached from the filling machine.
[0039] In accordance with the present invention, the vent tube used in the fill process is configured to incorporate a traceable material, such as an RFID tag, a magnet, or in some cases, both. A scanning system and/or method can then be incorporated to check for malfunctions in the filling process and also in which container a malfunctioning vent tube has landed. Further, other types of traceable materials can be used without deviating from the scope of the invention.
[0040] FIGS. 3A and 3B show an exploded view and an assembled view of a vent tube 16 containing a traceable material, respectively. The vent tube 16 comprises an RFID tag 18 , a magnet 22 , a vent tube head 24 , a hollow cylindrical body 26 and indentations 28 for assisting in connecting to the filling machine.
[0041] As described herein and in the preferred embodiment, the vent tube 16 incorporates an RFID tag 18 for detection when the vent tube detaches from the filling machine 10 . The vent tube 16 can be manufactured from material that will be determined by the standards of the food and beverage industry for each application. The RFID tag 18 can be attached to, or housed or enclosed in, the vent tube 16 through a machining or injection molding process as understood by one having ordinary skill in the art, such that in the preferred embodiment the RFID tag 18 is attached to, or housed or enclosed in, the vent tube head 24 .
[0042] The vent tube may also incorporate a magnet 22 for additional detection purposes. In some instances, the vent tube only uses a magnet 22 and not the RFID tag 18 . In accordance with the present invention, an RFID tag or other traceable material 18 can be placed on any type of vent tube used in the filling process, including ball cage vent tubes. Similar to the RFID tag above, the magnet 22 can be attached to the vent tube 16 in the same manner. The present invention can utilize the RFID tag 18 alone or in conjunction with the magnet 22 .
[0043] RFID systems have several components, such as chips, tags, readers and antennas, which can be used to determine the location of an RFID tag (and any item that the tag is attached to) from a distance away. In its simplest form, a small silicon chip is attached to a small flexible antenna to create a tag. The chip is used to record and store information and when a tag is to be read, the RFID reader or scanner send out a radio signal. The tag absorbs some of the RF energy from the reader signal and reflects it back as a return signal delivering information from the tag's memory.
[0044] The RFID tags 18 do not require a battery, as the power is supplied by the identification gate as understood by one having ordinary skill in the art. Any type of RFID tag 18 can be used in the present invention, Ultra-High Frequency (UHF), High Frequency (HF), and Low Frequency (LF), each providing its own advantages and disadvantages. The higher the frequency, the longer the range for detection; while the lower the frequency, the less power that is needed for the tag to operate. Ranges of 20 to 30 feet are obtainable for the UHF RFID tags, while the HF and LF RFID tags operate at approximate distances of 1 meter and 1 foot, respectively.
[0045] As an example, UHF tags operate within the 800 and 900 MHz band and provide a response from a range of 20-30 ft. RFID tags operating in the UHF range can transfer data much faster than RFID tags operating in the HF and LF bands. However, UHF RFID tags require more power than those operating at the HF and LF bands, and are suited more for applications when sensing through low density materials.
[0046] RFID tags operating in the HF range primarily operate at 13.56 MHz. These tags require a read distance typically of about 1 meter, and work well when sensing through metal and liquids. RFID tags operating in the LF band have an operating frequency of 125 kHz and work well sensing through product or materials with a high concentration of water. These LF tags must be read with equipment within about a one foot range. However, these LF RFID tags require the least amount of power of the three RFID tags described herein.
[0047] RFID readers or scanners are generally composed of a computer and a radio. The computer manages communications with the network or through the Programmable Logic Controller (PLC). The radio controls communication with the RFID tag, typically using a language dictated by a published protocol, such as the EPC Class 1 specification.
[0048] When the vent tube 16 of the present invention, containing the RFID tag 18 , is used in the filling process, an inspection system, such as an RFID reader, can be incorporated into the filling line or in numerous other locations to continuously check for vent tubes 16 that have detached from the filling machine 10 . As soon as a vent tube 16 containing an RFID tag 18 detaches from the filling machine 10 , the RFID reader determines that the vent tube 16 is no longer in the correct location and can be used to find the container 14 in which the vent tube 16 is located. This entire inspection and determination procedure takes seconds and can be incorporated into the filling system to immediately shut down the filling process as understood by one having ordinary skill in the art before many more containers are filled.
[0049] In the preferred embodiment, the system and methods of the present invention comprise incorporating or housing an RFID tag or transponder in a stainless steel vent tube, for use in glass bottle filling for example, and a plastic vent tube, for use in aluminum can filling for example. The vent tube may also incorporate a magnet along with the RFID transponder. Using an additional traceable material, such as a magnet, increases the detection of the vent tube in certain situations such as when the vent tube falls into an aluminum can and is sealed attenuating the signal.
[0050] The preferred embodiment of the system 40 and method is shown in FIG. 4 , in which there are three points of detection or identification of the vent tubes 16 during the filling process. The first point of detection 42 takes place while the vent tubes 16 are attached to the filler machine 10 . An RFID reader 42 is placed close to the filler 44 in a section where no containers 14 are present. As the filler 44 rotates in operation the reader 42 continuously reads the RFID tags 18 that are imbedded in the vent tubes 16 to ensure one or more has not become detached during the filling process. This section 42 of the system 40 will alert the operator if a vent tube 16 becomes detached from the filler 44 and will also provide data indicating the specific filler vent tube 16 position.
[0051] The second point of detection 46 takes place on the line after the container 14 has been seamed or sealed. This section 46 of the system 40 utilizes magnetic and inductive sensor technologies to detect the imbedded magnet 22 in the vent tube 16 (or the stainless steel vent tube). This section 46 of the system 40 provides an output to the operator that can be used in an auto reject system or at the operator's discretion.
[0052] The third point of detection utilizes a handheld RFID reader 48 . After the first 42 or second 46 detection process has identified a vent tube detachment, the operator can now scan the specific can or bottle with the handheld scanner 48 in order to verify the location of the detached vent tube 16 .
[0053] The present invention does not have to incorporate each of these detection points, and the system can use one or any combination of these detection points to detect and locate a malfunctioning vent tube or a vent tube that has broken off of the filling machine.
[0054] The first point of detection, the RFID reader 42 , which incorporates an antenna, can be integrated (i.e., through an RFID hardware and/or software integrator) into a local network at the filling site, or it can be connected through a global communications network, such as the Internet, to a remote site as understood by one having ordinary skill in the art. As such, the information received by the reader 42 at the antenna can be transmitted to a number of locations for informational purposes such as record keeping. Further, the second 46 and third 48 points can also be integrated into the system as a whole. Additionally, the system is not limited to three detection points, as the system is scalable and additional detection points can be added for other filling lines and for other scanning purposes, such as to make sure that none of the filled containers being loaded onto a truck have a broken vent tube located inside.
[0055] Also, each of the detection points can utilize one or more of the detection methodologies. So for example, the first point of detection 42 may only read RFID tags, while the handheld scanner 48 may be configured to scan for both RFID tags and the magnet.
[0056] Other embodiments for determining a malfunction in the filling process 10 , such as a vent tube 16 detaching from a filling machine 10 and falling into a container 14 , include determining the temperature variant in the bottle as the temperature will change quickly when a vent tube 16 falls into the container 14 filled with product. This embodiment employs measuring the temperature variant in the bottle 14 to detect if a vent tube 16 is present. In a similar manner, determining the change in bottle 14 capacitance, whereby the system measures the capacitance and/or change in capacitance in the bottle 14 , can be used to detect an inadvertent vent tube 16 . In this embodiment, a charge is applied to the bottle 14 and the system measures charge or discharge time.
[0057] Another embodiment for detecting a detached vent tube 16 include utilizing an inductive sensor, where a ferrous material 22 is injection molded inside or into the vent tube 16 , or a Hall Effect sensor, where a magnet 22 is injected molded inside or into a vent tube 16 . Additional sensors can be used to detect a modified vent tube 16 using Ultra Sonic, Infrasonic or Infrared sensors, or with the use of vision sensors.
[0058] It will be understood that the embodiments of the present invention which have been described are illustrative of some of the applications of the principles of the present invention. Numerous modifications may be made by those skilled in the art without departing from the true spirit and scope of the invention. | The present invention is directed to a vent tube apparatus, system and methods incorporating a traceable material such as a Radio Frequency Identification (RFID) tag for use in conjunction with a filling machine during container filling operations for a quicker and more accurate detection of the location of the vent tube after it has become detached from a filling machine during filling operations, and to increase the safety of the filling operation and reduce costs and time when a malfunction occurs. | 1 |
BACKGROUND
[0001] Because of the ongoing miniaturisation, precision mechanics is becoming more and more important and this requires very high precision tools. High-speed cutting is one of the best ways to get a very high precision. Another advantage of very high-speed cutting is the fact that from a certain speed cutting forces and temperatures decrease as stated by Salomon in his Salomon curves. Another advantage of very high-speed cutting is that there is no need for using cutting fluids, which makes very high-speed cutting environmentally attractive. With environmental legislation becoming more and more severe high-speed cutting becomes more and more attractive.
[0002] The problem with high-speed cutting is that high-speed machines they are difficult to build. It is known that high-speed cutting technology is subject to the conflict of combining high processing/machining speed and high precision. This invention contributes to the construction of high speed and high precision rotating machines in general and cutting tools in particular.
[0003] A possible solution would be that a high speed and high precision cutting tool like a grinding wheel is made monolithic with its shaft, otherwise the high surface speed (which is the objective to be reached) will cause bursting of the rotating device/tool/blade owing to centrifugal forces. The problems with employing a monolithic rotating device/tool/blade are that, with the classical bearing systems, (i) replacing the rotating device, for instance the cutting tool, e.g. for the purpose of re-coating or revising in general, becomes very difficult; (ii) it would be very difficult to achieve good centricity of the axis of rotation, and (iii) Owing to the small (ball) bearing bores needed to achieve high speeds, the shaft has to be made small, which can lead to rotor dynamic instabilities. This makes it impossible to implement high-speed cutting with a monolithic cutting tool in an industrial environment where tool replacements are executed regularly. In general machinery wherein rotating device has to achieve a very high tip velocity, which is mainly a function of spindle speed and cutter size, are characterised in that they have above mentioned problems.
[0004] The present invention, however, overcomes these problems. With this new bearing system which uses the sides of the rotating device, e.g. the sides of a cutting tool as a counter-surface for the bearings it is possible to use the advantages of a monolithic cutting tool on an industrial scale because it is easy to change the cutting tool. It was proven with a prototype of this invention that after exchanging the cutting tool the machine is as accurate as before.
SUMMARY OF THE INVENTION
[0005] This invention solves a fundamental problem of high-speed rotating devices. In order to have sufficient strength against bursting, the rotating device (e.g. cutting tool or milling wheel) has to be made monolithic with its shaft. Problems of the difficulty to provide effective bearing system to the rotating devise such that will ensure a stable, smooth and precise running and at the same time enable easy tool exchange has been overcome by a new bearing system. The invention provides an enhanced fluid film bearing system for high speed rotating tools, preferably cutting tools. The new bearing system allows higher precision and higher speeds combined with fast tool changing. The high precision and higher attainable speeds are the result of the fact that both journal and thrust bearing are placed close to the cutting tool which results in a very stiff construction and of the fact that the cutting tool is monolithic with its shaft. The fast tool changing is made possible by having one end of the bearing system removable. After this is done, the whole axis with the cutting tool can be removed. This is only possible because the sides of the cutting tool are used as a thrust bearing surfaces.
ILLUSTRATIVE EMBODIMENTS OF THE INVENTION
BRIEF DESCRIPTION OF THE DRAWINGS
[0006] FIG. 1 is a cross-sectional view of an embodiment of a rotating device, for instance a rotating wheel or a cutting tool and preferably a grinding wheel. A possible application is high speed cutting, high speed grinding or High Speed Chipping (HSCh). Motor and rotating device, rotating wheel or grinding wheel are on different axes.
[0007] FIG. 2 is a detail of FIG. 1 illustrating the present invention.
[0008] FIG. 3 is a view of the monolithic tool-shaft illustrating the thrust bearing surfaces on the sides of the rotating device.
[0009] FIG. 4 is a cross-sectional view of an embodiment of a grinding wheel according to the present invention. The application is grinding. Motor and rotating device (e.g. grinding wheel or cutting tool) are on the same axis.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0010] FIG. 1 illustrates an embodiment of the invention, as it was build by the inventors. It is a high speed rotating device, preferably a grinding spindle or a cutting tool, with a motor on a separate axis. The rotating device (e.g. grinding wheel or cutting tool) 1 is monolithic with its shaft. Monolithic as defined in this application, does not mean that the rotating device (e.g. grinding wheel or cutting blade) and the shaft have necessarily to be made from a single material. The shaft-disc combination may indeed be fabricated from a combination of materials or composites, using a variety of techniques such as gluing, welding or shrink fitting. Therefore, the term monolithic in this application means that the shaft-disc combination is fabricated as one whole, in a suitable way so as to withstand the high stresses that are induced by centrifugal forces upon rotation, and that it is not practical to dismantle them after fabrication. The motor 2 is mounted on a separate axis. The two axes are joined with a coupling 3 that allows easy mounting and dismounting.
[0011] FIG. 2 illustrates better the bearing system. In this embodiment it is a fluid bearing system, preferably a gas bearing system. However, it may be any fluid bearing of the hydrostatic and/or the hydrodynamic type, or it may be a magnetic bearing. The tool 1 , in this embodiment a grinding wheel, is supported by a fixed thrust and journal bearing 2 at one side and a removable thrust bearing 3 and journal bearing 4 at the other side of the cutting tool. The thrust bearings 2 and 3 use the sides, i.e. the faces, of the monolithic tool-shaft 1 as a bearing surface. The said sides or faces are flat in a preferred embodiment. But, it may have any shape of a surface of revolution, e.g. spherical (concave or convex) or conical. The thrust-and-journal bearing 2 is fixed in the housing 5 . The thrust bearing 3 and the journal bearing 4 are mounted in the cover 6 with bolts 9 . The cover 6 together with bearings 3 and 4 can be dismounted from the housing 5 . Then the monolithic wheel-shaft 1 can be dismounted. A new axis unit can be mounted and the cover 6 together with bearings 3 and 4 is mounted again. Guiding Dowel pins 7 ensure that the cover 6 and radial bearing 4 are replaced in the exact same radial position as before. The springs 8 position bearing 3 and set the thrust bearing force by turning bolts 10 . The shaft is provided on each side with (tap) holes 11 for dynamic balancing.
[0012] With the construction presented above high precision bearing system are obtainable that can be easily dismounted for tool revision/up-hauling.
[0013] FIG. 3 shows the monolithic shaft-tool combination of FIGS. 1 and 2 in detail. It demonstrates the journal and thrust bearing surfaces. The journal bearing surfaces are on both sides of the cutting tool, the thrust bearing surfaces are located on the faces of the cutting tool. It is also possible to combine the radial and thrust action of on both sides by making journal and thrust surfaces, on each side, one continuous surface, e.g. conical or spherical, or any other suitable surface of revolution.
[0014] FIG. 4 shows another embodiment of the invention. In FIG. 4 the rotor of the motor 1 is mounted on the same axis 2 as the rotating device (e.g. cutting tool or grinding wheel). This makes a very compact construction possible and overcomes problems with the coupling. A special and very compact construction is obtained by embedding the rotor of the motor 1 inside the shaft of the tool, or in the tool (disc), and the stator 7 into the radial bearing or the thrust bearing respectively. It is important to note, in this regard, that the motor may be an electric A.C. or D.C. motor, or it can be a turbine or a viscous (laminar) motor that are driven by a fluid (i.e. liquid or gas). The bearings used are one fixed journal-and-thrust bearing combination 3 at the left side and at the right side one floating thrust bearing 4 combined with a journal bearing 5 . Bearings 4 and 5 are fixed in the cover 6 . The tool change is done in the same way as in the first embodiment.
[0015] Present invention involves an apparatus comprising a rotating tool or a rotating blade, preferably a milling wheel or a cutting tool that is monolithic with a shaft and a fluid film bearing system wherein the fluid film bearing system comprises two thrust bearings (axial bearings) at both coaxial surfaces of the blade and further comprising two journal bearings (radial bearings) positioned at the shaft. Such apparatus may be designed for balanced high-speed rotation. It may be a high-speed rotation apparatus, wherein said rotating tool is a disc. The rotating tool of this apparatus maybe a wheel, a disc, a rotor, a cutter, a blade or a drum.
[0016] Moreover the rotating tool may comprises magnets, an illumination source, or one or more sensor for high-speed detection or high-speed imaging.
[0017] In one embodiment of present invention the rotating tool is allowed to rotated at at least 10,000 rpm, preferably at 20,000 to 100,000 rpm and most preferably at 40,000 to 100,000 rpm. The apparatus may comprise a rotating tool that can be rotated at a surface speed of above between 1 km/min, preferably at a surface speed of above 10 km/min, and most preferably at a surface speed 10 km/min to 30 km/min.
[0018] The apparatus of present invention can comprise a high-speed cutting tool or a high-speed imaging tool. It can be an apparatus used for high-speed cutting. Or it can be an apparatus used for high-speed photography.
[0019] The apparatus of present invention can be designed in that during rotation better process stability is achieved than with conventional machinery or that during rotation better precision and process reliability is achieved than with conventional machinery.
[0020] In one embodiment a motor mounted on a different axis drives the apparatus. In another embodiment a motor mounted on the same axis drives the apparatus. In yet another embodiment the apparatus is driven by an electric motor and in yet another embodiment of present invention a turbine drives the apparatus.
[0021] A further embodiment of present invention comprises a high precision and high speed rotation device, comprising 1) a fluid (gas or liquid) bearing system which is a combined journal bearing and thrust bearing and 2) a blade which is monolithic with a shaft, wherein the thrust bearing uses the sides of the blade as a thrust bearing surfaces and journal bearings uses the shaft as journal bearing surface and wherein the blade is positioned between the two thrust bearings.
[0022] Yet another embodiment of present invention comprises a fluid bearing system for stabilising high speed rotation, characterised in that said bearing system is a combined journal and thrust bearing system, that the thrust bearing uses the sides of the rotating tool as a bearing surface, that the rotating tool being positioned between to two bearings and that the rotating tool is monolithic with the shaft. This bearing system may be used with a combination of self acting and externally fed fluid film bearings, with magnetic bearings, with specially designed rolling element bearings. The bearings of this system may combine both bearing and motor function. | A solution is presented for high speed rotating devices, in particular cutting tools, whereby the said rotating device ( 1 ) is made monolithic with its shaft and the bearing system, needed to support it during rotation, uses the surfaces of the rotating device ( 1 ) as bearing surfaces. In the preferred embodiment, the fluid film bearing system includes two journal bearings ( 2,4 ) on both sides of the cutting tool and two thrust bearings ( 2,3 ), which use the faces of the cutting tool ( 1 ) as bearing surfaces | 5 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a valve stem assembly in internal combustion engines.
2. Description of the Prior Art
Heretofore various means have been developed for the purpose of attaching a valve spring retainer to the distal end of the valve stem.
One prior means utilizes two wedge-shaped key members. Each key member includes a projection for extending into a recess in the distal end of the valve stem to accurately position each key member on the distal end of the valve stem with the upper portion of each key member being substantially flush with the tip of the distal end of the valve stem. However, this device is disadvantageous since, for example, a normal cup-shaped lash cap cannot be used therewith.
A similar prior means of attaching a valve stem to a valve spring retainer is one developed by Chrysler Corporation for use in its 426 Hemi engine and is composed of two key members similar to the above means but the top of each key member is removed to accomodate a cup-shaped lash cap in a recess then formed between the side of the distal end of the valve stem and the inner edge of the valve stem retainer. One purpose of the lash cap is to present an enlarged bearing surface for the rocker arm to contact as will be apparent to those skilled in the art. However, this means is disadvantageous in that when the upper portion of the key members is removed the lock will lose a great deal of strength making it disadvantageous for use in certain conditions.
Another prior means was developed by Crane Cams and is similar in that each of the two key members (identified by the Crane Cams part number 99093) has a projection for extending into a groove in the distal end of the valve stem and the upper portion of each wedge-shaped key member is again removed for receiving the lash cap, but the upper portion of these key members is thicker than the above described key members. Each of these key members is also longer than the Chrysler Corporation key members because Crane Cams extended the lower portion down the side of the valve stem. However, due to the inherent weakness caused by the loss of the upper portion this device is still disadvantageous in extreme conditions.
Heretofore, various patents have been issued relating generally to the present invention. See, for example: Engemann, U.S. Pat. No. 2,827,891; Cousino, U.S. Pat. No. 3,021,593; Bush, U.S. Pat. No. 3,077,874; Thompson, U.S. Pat. No. 3,298,337; Iskenderian, U.S. Pat. No. 3,853,101; and Toth, U.S. Pat. No. 3,978,830. None of the above patents disclose or suggest the present invention.
SUMMARY OF THE INVENTION
The present invention is directed towards overcoming the problems and disadvantages of prior means for locking or attaching a valve spring retainer and a valve stem together. The concept of the present invention is to provide such a lock means which allows a cup-shaped lash cap to be utilized in conjunction with the valve spring retainer and valve stem and which includes means for being wedged between the valve spring retainer and the valve stem to lock the valve spring retainer and the valve stem together, and for receiving a portion of the lash cap.
Preferably, the valve lock means of the present invention includes two wedge-shaped key members for being wedged between the valve spring retainer and the valve stem. Each key member preferably includes a cavity for receiving a portion of the lash cap. Further, the improved valve lock means has substantial advantanges such as increased strength in that the valve assembly is much less likely to fail under extreme conditions. The improved valve lock means also has an enlarged surface area capable of receiving a roller or a conventional type rocker arm. The improved valve lock means also is designed for use with a standard valve stem and lash cap so that these parts do not need to be modified. Further objects and advantages of the present invention will become apparent to those skilled in the art from the following detailed description made with reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side elevational view of the valve lock means of the present invention shown associated with a valve assembly.
FIG. 2 is an enlarged sectional view of a portion thereof as taken from line II--II of FIG. 1.
FIG. 3 is a top plan view of a portion of the valve lock means of the present invention.
FIG. 4 is a side elevational view thereof.
FIG. 5 is a sectional view of a portion of the valve lock means as taken from line V--V of FIG. 2.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The valve lock means 11 of the present invention is for use in a valve assembly of a high performance internal combustion motor or engine such as commonly used in the sport of automobile racing to lock or attach a valve spring retainer 13 to the distal end 15' of a valve stem 15 in such a manner that a typical cup-shaped lash cap 17 can be positioned or placed over the tip T of the distal end 15' of the valve stem 15 (see, in general, FIGS. 1 and 2). The purpose and operation of the valve spring retainer 13, valve stem 15 and lash cap 17 is not affected or changed by the valve lock means 11 of the present invention and is well known to those skilled in the art. In general, the valve lock means 11 of the present invention includes means for being wedged between the valve spring retainer 13 and the valve stem 15 to thereby lock or attach the valve spring retainer 13 and the valve stem 15 together as will be apparent to those skilled in the art, and for receiving a portion of the lash cap 17 (see, in general, FIG. 2).
Preferably, the valve lock means 11 of the present invention includes a first wedge-shaped key member 19 and a second wedge-shaped key member 21 for being wedged between the valve spring retainer 13 and the valve stem 15 as shown in FIGS. 2 and 5 to lock or attach the valve spring retainer 13 and the valve spring 15 together. Each key member 19, 21 preferably has a cavity or cavity-like portion 23 for receiving a portion of the lash cap 17. More specifically, a first end 19a, 21a of each key member 19, 21 is preferably provided with an offset consisting of a shoulder portion 25 and a wall portion 27 located conterminous with and substantially perpendicular to one another as clearly shown in FIGS. 2 and 4 so as to define the cavity-like portions 23 as will hereinafter become apparent.
The lash cap 17 includes a cup-like cavity 17' substantially the same shape and size as the distal end 15' of the valve stem 15 for allowing the lash cap 17 to be positioned or placed over the tip T of the valve stem 15 as shown in FIG. 2. The lash cap 17 includes an annular rim 17" which, when the lash cap 17 is positioned or placed over the tip T of the valve stem 15, extends downward past the tip T of the valve stem 15 (see FIG. 2). The rim 17" of the lash cap 17 extends into the cavity-like portions 23 of the key member 19, 21 as clearly shown in FIG. 2 with the rim 17" of the lash cap 17 substantially contacting the shoulder portions 25 of the cavity-like portions 23 and with a portion of the outer wall 17'" of the lash cap 17 contacting the wall portions 27 of the cavity-like portions 23.
Each key member 19, 21 preferably is in the form of or has the cross-sectional shape of substantially half a circular ring so that when the key members 19, 21 are placed substantially together they will form a substantially complete circular ring so as to substantially completely enclose the valve stem 15 as clearly shown in FIG. 5. The outer walls 19b, 21b of each key member 19, 21 preferably slopes inwardly from the first ends 19a, 21a thereof towards the second ends 19c, 21c thereof relative to the inner walls 19d, 21d thereof so that the key members 19, 21 will function as wedges to lock or attach the valve spring retainer 3 and the valve stem 15 together (see, for example, FIG. 2). The angle of the outer walls 19b, 21b of the key members 19, 21 is preferably substantially the same as the angle of the inner wall 13' of the valve spring retainer 13. The inventor has determined that optimum strength is obtained when the outer walls 19b, 21b of the key members 19, 21 and the inner wall 13' of the valve spring retainer 13 are at an angle of substantially 10° relative to the longitudinal axis of the valve stem 15.
The inner walls 19d, 21d of the first and second key members 19, 21 preferably include a projection 29 for coacting with a groove 31 provided in the distal end 15' of the valve stem 15 remote from the tip T thereof (see FIG. 2) to allow, among other things well known to those skilled in the art, the key members 19, 21 and, therefore, the valve spring retainer 13 to be properly positioned relative to the tip T of the valve stem 15.
The key members 19, 21 of the valve lock means 11 are preferably constructed of titanium steel or the like in any manner apparent to those skilled in the art. The other components of the valve assembly may be constructed in any typical manner and of any typical material as now practiced and as well known to those skilled in the art. However, it should be noted that the angle of the inner wall 13' of the valve spring retainer 13 should be substantially complementary with the angle of the outer walls 19b, 21b of the key member 19, 21 and that, as heretofore mentioned, these angles should be substantially 10° relative to the longitudinal axis of the valve stem 15 for optimum strength.
The use of the valve lock means 11 of the present invention is quite simple. The assembly procedures of the valve assembly utilizing the valve lock means 11 of the present invention is substantially identical to those of any typical prior valve assembly and will be apparent to those skilled in the art. For example, the first step is to compress the valve spring 33 and insert the valve spring retainer 13 over the distal end 15' of the valve stem 15. Next, the key members 19, 21 are placed about the distal end 15' of the valve stem 15 with the projections 21 extending into the groove 31. When the valve spring 33 is released, it will force the valve spring retainer 13 upward and into wedgeable engagement with the key members 17, 21 to thereby lock or attach the valve spring retainer 13 and the valve stem 15 together. It should be noted that they key members 19, 21 and the valve spring retainer 13 are shown spaced apart from one another in FIG. 2 for the sake of clarity. Next, the lash cap 17 is positioned or placed over the tip T of the valve stem 15 so that the rim 17" and a portion of the outer wall 17'" thereof will extend into an annular cavity-like portion defined by the exterior of the valve stem 15 and the shoulder portion 25 and the wall portion 27 of the key members 19, 21. Such a valve assembly, when used in a high performance internal combustion engine in conjunction with a roller-type rocker arm 35 or the like, is extremely secure from failure caused by movement of the valve spring retainer 13 relative to the valve stem 15.
As thus constructed and used, the present invention provides an improved valve lock means and an improved valve assembly which is extremely strong even when a lash cap is utilized therewith since the wedge-like key members of the lock means extend above the rim of the lash cap and surround or receive a portion of the body of the lash cap.
Although the present invention has been described and illustrated with respect to a preferred embodiment thereof it is not to be so limited since changes and modifications may be made therein which are within the full intended scope of the invention. | A device for attaching a valve stem to a valve spring retainer. The device includes two wedge-like key members for wedgably locking the valve spring retainer to the valve stem. Each key member has a cavity for receiving a portion of a cup-shaped lash cap which is mounted on the distal end of the valve stem. | 5 |
BACKGROUND OF THE INVENTION
The present invention relates to articulated seabed mattresses for the protection and stabilisation of seabed installations such as pipelines.
The use of articulated mattresses in offshore coastal and marine engineering is well known for stabilisation, protection and scour prevention of pipelines, flowline umbilicals, seabed templates, steel and concrete platforms and the like. These mattresses are particularly useful in areas of high bottom current where hydro-dynamic forces are considerable. Thus, for example, a seabed pipeline can be covered with such a mattress so that the pipeline is stabilised by the weight of the blanket thereon and also the adjacent seabed is protected against erosion. Examples of articulated mattresses and their use are given for example in European patent specification 152232A. Generally, these mattresses comprise concrete or similar elements joined together to allow relative articulation.
Subsea stabilisation mattresses can be relatively massive, eg. a mat of 5 m×2 m would weigh (in air) over 2.5 tons. However, even so, when they are laid over a seabed pipeline, for example, they can still be prone to movement during a storm or tidal surge. While, in theory, greater stability could be obtained by increasing the mat weight, we have found another way of dealing with this problem.
Further, in addition to stability in extreme storm conditions, a stabilisation mattress should desirably also be capable of withstanding the impact thereon of anchors or trawlboards travelling laterally, or dropped objects travelling largely vertically.
We have now devised a new design of sub-sea mattress which can provide substantial advantages in use over prior known mattresses.
In accordance with one aspect of the present invention, there is provided an articulated mattress for laying on a seabed or the like, which comprises a plurality of concrete or like members articulated together, characterised in that the mattress has a relatively thick region from which its thickness tapers to at least one side edge.
In a simple embodiment, a mattress of the invention is generally wedge-shaped. That is to say, when laid on a horizontal surface, its transverse sectional shape is roughly that of a right-angle triangle. More usually, however, mattresses of the invention will have a shape generally similar to that of a ridge tent, i.e. with a central elongate thick region tapering down on each side to a side edge of the mattress. Another possibility is to have a generally pyramidal shape, i.e. a central thick region tapering down on all sides to the edge(s). In all cases, the upper sloping surface(s) may be generally flat, or generally curved, eg. concave or convex as desired. Whilst the commonest mattress shape in plan is generally rectangular, in fact the mattresses can be of any desired plan shape as required in practice.
By providing the mattress with its own taper from a thin edge to a much thicker region, improved stability can be achieved and also improved ability to withstand lateral impact by dragged anchors or trawlboards, for example, and by dropped objects descending vertically.
The mattresses of the invention taper in thickness from a relatively thick region to at least one side edge. Normally, the tapering extends through at least two of the constituent elements of the mattress.
Conventionally, when a sea-bed pipeline or other object is to be protected, a subsea mattress is laid thereover. In accordance with a highly preferred feature of the present invention, the underside of a mattress is provided with a recessed region in which the object to be protected is received. Such a recessed region is most advantageously provided in the thick region of the mattress. This gives excellent protection to the object and also allows certain further preferred features of the invention to be adopted (described hereinafter).
The mattresses of the invention are constructed from massive elements formed from concrete or other weighty material. The concrete can be adjusted to have a low specific gravity, 1.5 t/m 3 for high conditions where seabed soils have little bearing strength, up to 4.7 t/m 3 for high current applications where additional weight is required to cope with extreme seabed currents which can be as high as 10 m/s. The mattress elements are connected by rope, hinge, geotextile or other flexible connection mechanism so that the mattress folds during deployment and the joints between the elements allow sufficient flexibility to accommodate normal seabed discontinuities.
In the mattresses of the invention, the relatively thick region will normally be made of correspondingly thick concrete (or the like) elements with gradually thinner elements being used towards the edges to give the desired taper. the outermost elements will most preferably be shaped to give protection against scour.
In a much preferred arrangement of the invention, the thick region of the mattress (which will normally be constituted by one element, although a group of two or more can be used) has on its underside a recess to receive the object to be protected, eg. part of a pipeline. Thus, such a mattress is placed over the pipeline which is received in the recessed region. This region of the pipeline is preferably encapsulated and so protected against environmental and damage loads. The pipeline need not necessarily touch the mattress at all. Thus, the thick recessed region of the mattress can straddle the pipeline without contacting it.
For certain applications where thermal expansion may be substantial and considerable movement within the recess is anticipated, or the recess is required to bear directly onto the pipeline, and when the pipeline has a special coating such as an insulating coating, the recess is preferably coated with a suitable anti-abrasion coating which could for example be a high build paint, or sheet of material such as polypropylene or polyester suitably attached to the inner surface of the recess.
At the bottom of the mattress, at the edge of any recess, there is preferably a cusp to ensure that the pipeline is retained within the recess regardless of the extent of any lateral movement. This cusp may be extended for certain applications so that it penetrates the seabed locally to enhance its ability to retain the pipeline within the recess.
The individual mattress elements can, for example, incorporate a contoured underside to increase the frictional resistance of the seabed and thereby provide additional lateral restraint.
The individual mattress elements are preferably slab-sided to ensure that adjacent matteress elements do not fold or buckle upward when a lateral force is applied. The upper surfaces of the individual elements can be contoured to reduce the hydro-dynamic lift on the elements when they lie in a lateral current flow. This flow would tend to destabilise and move the mattress in extreme water particle velocity conditions. The overall profile of the mattresses of the invention, i.e. progressive tapering from the thick region (preferably central) to the edge(s), enhances the stability of the mattress by providing a positive pressure build up on the upstream face which enhances the frictional effects which resist lateral movements and counteract the lift effects produced on the downstream face.
In recent times, it has become important to be able to pass hot materials through seabed pipelines without large heat losses. In order to achieve this, it has been necessary to use insulated pipes (which are expensive) and to locate the pipelines in trenches dug in the seabed. This is a very expensive installation and, moreover, suffers certain other disadvantages. In particular, pipelines which carry hot materials suffer substantial thermal expansion and contraction, and this has resulted in buckling of the pipelines in trenches and in damage to the pipelines themselves. We have now found, in accordance with a preferred feature of the present invention, that the mattresses of the present invention with a tunnel in their thick region, are excellent for protecting high-temperature pipelines. Use of such mattresses can obviate completely the necessity for trenches. The tunnels allow for lateral movement of the pipelines, to take up thermal dimensional changes. Also, the tunnel itself provides some small amount of thermal insulation.
In accordance with a further preferred feature of the invention, the tunnel can be filled with a heat insulant to further protect the pipeline against thermal losses. Thus, the insulation is provided to the pipeline on the seabed after the mattress has been laid on the pipeline. When a mattress of the invention is laid on a pipeline with the latter in the mattress tunnel, the space between the pipe and the mattress can be filled, or partly filled, with an insulating material. A preferred insulating material is a cementitious grout which can be flowed into the space between the pipe and the mattress, and allowed to set.
In many (but not all) cases, it is preferred to provide a flexible bag or other container for the insulation material, between the pipe and the mattress, for example to receive and contain a fluid grout in position while it cures. The container will normally be positioned in the tunnel to lie between the mattress and the pipe during installation of the mattress, and may thereafter be filled with insulant. Alternatively, and usually far less preferably, the container can sometimes be positioned after installation of the mattress.
Conveniently, the container will include at least one inlet accessible from outside the overlying mattress, for introduction of insulant into the container. A preferred form of container is a flexible bag, but other types of container can be used.
The principal function of any bags or other containers is to hold the grout or other insulant in position, especially during any curing thereof. The container is flexible to allow the insulant to conform to the shape of the pipe and so form a coating thereover. Another function of the containers can be to assist in relieving thermal stresses. Thus, as the temperature of a pipeline varies, so it expands and contracts. We have found, in accordance with a preferred feature of the invention, that by using a container of woven, rubber or another compressible material, the material itself (sandwiched between the insulation and pipeline) can absorb or reduce the effect of thermal stresses on the insulation coating.
In order that the invention may be more fully understood, various embodiments thereof will now be described, by way of example only, with reference to the accompanying drawings, wherein:
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an orthogonal view of a first embodiment of mattress of the invention.
FIG. 1A is a schematic end elevation of a second embodiment of mattress of the invention.
FIG. 2 is a schematic sectional view of a third embodiment of mattress of the invention laid over a seabed pipeline.
FIG. 3 is an orthogonal view of a fourth embodiment of mattress of the invention.
FIG. 4 is a top plan view of the mattress of FIG. 3.
FIG. 5 shows the mattress of FIG. 3 in folded condition.
FIG. 6 is part of FIG. 5 on a larger scale to show a detail.
FIG. 7 schematically illustrates in section a modified element for a mattress of the invention.
FIG. 8 illustrates the mattress of FIG. 3 laid over a seabed pipeline.
FIGS. 9-11 are schematic cross-sectional views of the general arrangement of FIG. 8 but showing the provision of insulation.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to the drawings, the mattress of FIG. 1 comprises three elongate concrete members or elements 1,2 and 3, lying side-by-side. Member 1 is the thickest, and the thickness tapers down via member 2 to the side edge 4 of the member 3. (In this specification, thickness means the vertical distance from the bottom of a mattress to the top when it is lying on a flat surface.) Ropes or cables 5 are embedded in the members to link them together. At side edge 4, the ropes 5 can be formed into external loops 6 for securing the mattress, for example. The adjacent upper edges 7,8,9 and 10, of the three members 1,2 and 3, are relieved or chamfered, and the ropes 5 extend between the adjacent elements close to these edges, so that the mat can articulate. Thus, as drawn, members 2 and 3 can pivot on an axis close to their respective edges 9,10, and likewise members 1 and 2 can pivot about an axis close to their edges 7,8.
As can be seen, the end elevation of the mattress of FIG. 1 is that of a right-angled triangle with member 1 including the right-angle (11). Overall, the mattress tapers in thickness from member 1 to the side edge 4 of member 3.
The embodiment of FIG. 1A is a five-member mattress, comprising an elongate central thick member 15, having on each of its sides two further members 16,16' and 17,17' which respectively taper to opposed side edges 18,18'. The members are joined together with embedded ropes or cables 19 as in FIG. 1 and have relieved upper edges 20 to permit articulation.
FIG. 2 shows a third embodiment of mattress of the invention, in use with a seabed pipeline 20. The mattress itself is made up essentially of two of the mattresses of FIG. 1 joined with the thickest elements adjacent. Thus, in FIG. 2, the mattress comprises three elongate concrete elements 21,22 and 23 on one side of the pipeline 20, and three similar elements 24,25 and 26 on the other side. Each group of three elements forms a wedge shape tapering from the thickest element 21,24 outwardly to the edge 27 or 28 of the outer elements 23,26. The elements 21-26 are held together by embedded ropes or the like 29 and have chamfered corners 30 to allow articulation (as in FIG. 1). The two thickest elements 21,24 are spaced apart to seat each side of pipeline 20, with the interconnecting ropes 29 straddling the pipeline 20. Thus, the height of the thickest elements 21,24 is about the same as that of pipeline 20.
FIG. 3 shows a fourth embodiment of mattress of the invention. As shown, the mattress comprises five elongate shaped concrete (or the like) elements 31-35 lying in parallel. Overall, the end elevation is generally that of an obtuse-angled triangle, the obtuse angle being at the top of central element 33. Each side of this element, the thickness of the mat tapers down to a side edge 36,37. As in FIGS. 1,1A and 2, the top edges of the elements are chamfered as at 38, to permit articulation, the elements being joined by embedded ropes.
FIG. 4 is a top plan view of the mattress of FIG. 3, and like numerals indicate like parts. The embedded ropes 40 can provide loops 41 (only four shown) at the opposed side edges 36,37 if desired. A typical size of this mattress might be width 2 m, length 5 to 6 m, and thickness 1/2 m.
FIG. 6 illustrates the junction between elements 32 and 33, showing embedded rope 40 and the chamfered top edges to permit relative pivoting about the interlinking rope sections 41.
FIG. 7 illustrates simply, by way of example, a concrete member such as one of those of FIG. 3, provided with a profiled base 70 to improve grip on the seabed. The normal planar base surface has been modified to increase frictional resistance against lateral movement of the mattress when placed on the seabed. Various shapes can be employed on the base for this purpose.
FIG. 5 shows the mattress of FIG. 3 but in a folded condition for transport. It will be observed that the outer members 31,32 have been folded back over central member 33, as have outer members 34,35, thus making a compact substantially rectangularly profiled unit which facilitates stacking for storage and transport. It is noted in this connection that, as drawn, members 31,32,34 and 35 are all of the same width equal to a quarter of the width of central member 33. However, other different relative preparations can be used. For example, if the central member is 60% of the mat width, folding will result in the apex of the member extending upwardly, but it can be received in the tunnel of another such folded mat stacked on top. FIG. 5 also shows the presence of elongate reinforcing elements 50 running longitudinally within each concrete member 31-35 to provide strengthening thereof.
An important feature of the mattress of FIGS. 3 to 6 is the provision of a tunnel 60 in the underside of the central member 33. This tunnel extends the full length of the member and can if desired have an anti-abrasion coating (now shown) on the walls thereof. The tunnel 60 is to receive one or more seabed pipelines 70 as shown, for example, in FIG. 8. As illustrated, the outer diameter of the pipeline 70 is about the same as the height of the tunnel 60, so that the top 61 of the tunnel bears down on the pipeline 70 to positively stabilise it. The width of the tunnel 60 is greater than the diameter of the pipeline 70 to allow lateral movement of the latter as desired. It is not essential for the tunnel height ot equal the diameter of the pipeline. In can be greater so that the mattress does not bear down upon the pipeline.
FIGS. 9 to 11 illustrate a further preferred feature of the invention, namely the provision of an insulating material in tunnel 60 of the mattress of the general type shown in FIG. 3, when in use on the seabed. FIG. 9 shows the same mattress/pipeline arrangement as in FIG. 8. However, on each side of the pipeline 70 in tunnel 60 there is provided an insulation bag 90,91 which (as shown) is filled with an insulating material 92. The insulant 92 can be a cement grout or more preferably a material which does not set hard, so still permitting some movement of the pipeline. Containment of the insulant in bags 90,91 prevents loss and confines the material around the pipeline 70 where it is needed.
FIGS. 10 and 11 illustrate one way of providing insulation material in the tunnel 60 of a mattress of the invention. These Figures illustrate the case where pipeline 70 has a diameter smaller than the height of the tunnel. As shown, the central member 33 of the mattress has one or more inlet channels 100 therein passing from the upper face 101 of the member 33 to the tunnel 60, and communicating with bags 90,91 for receiving insulant. There is one bag on each side of pipeline 70. A vent channel 102 can also be provided to allow fluid to be displaced from the tunnel 60 as the bags 90,91 are filled.
In order to provide the insulation in the tunnel, insulant material 92 is pumped through channel 100 into the bags 90,91 to expand and fill them. The bags conform to the outer surface of pipeline 70 so providing a close thermal insulation there around.
In use of the mattresses of the invention, they provide excellent stability and protection to seabed installations such as (but not only) seabed pipelines. The mattresses of the type shown in FIG. 1 can, for example, be laid on the seabed with the thickest element 1 abutting an installation. This is to provide substantial protection of the installation especially if the installation height is about the same as the height (or thickness) of element 1. This sort of use is illustrated in FIG. 2, although here there are (in effect) two mattresses of FIG. 1.
The mattress of FIGS. 3 to 6 is especially designed to be laid over a seabed installation (such as a pipeline) to provide substantial stabilisation and protection. The mattress is especially useful for pipelines carrying hot materials. Such pipelines need protection, but also must be allowed to expand and contract without damage. By locating these pipelines in a tunnel of a mattress of the invention, they are not only protected but are also permitted lateral movement (to take up thermal expansion/contraction) without damage. Furthermore, if necessary, insulation can be provided around the pipeline in the tunnel to minimise heat losses. | A concrete or like articulated mattress for protection of seabed installations comprises a plurality of concrete elements (31, 32, 33, 34, 35) articulated together, the mattress having a relatively thick central block (33) from which its thickness tapers through side blocks (31, 32, 34, 35) to side edges (36, 37). In the central block (33) a tunnel (60) is provided to accomodate a seabed installation such as a pipeline to be protected. Prior to installation on a seabed, the side blocks (31, 32, 34, 35) may be folded over and stored on the top of the central block (33). | 5 |
FIELD OF THE INVENTION
This invention relates to data recovery procedures in hierarchical, demand/response direct access storage device (DASD) subsystems and, more particularly, for managing status reporting to a host operating system as the attached DASD subsystem resolves detected anomalies.
DESCRIPTION OF RELATED ART
The disclosure is initiated with definitions relating to fault and failure, and continues with a brief discussion of hierarchical storage management systems. The section ends with discussions of the prior art modes of managing faults and failures in storage subsystems actively and passively where nesting failures upward can prematurely cause applications at hosts to abort.
Nomenclature of Faults, Failures, and Fault Tolerance
It is to be appreciated that in an information handling system, a "fault" is defined as a malfunction due to any one of several causes. In this regard, a fault may occur on either a transient, intermittent, or permanent basis. Also, a fault may be classified as either a "fail-silent fault" or a "Byzantine fault". Relatedly, a fail-silent fault is that type of malfunction wherein a component just terminates its performance, while a Byzantine fault is an undetected fault condition caused by hardware, software, or both. Technically, a system is said to "fail" when its behavior or activities do not conform to a specification. The same may be said for a "subsystem failure" or a "device failure".
"Fault tolerance" is the degree to which an information handling system, subsystem, device, or component can continue to operate notwithstanding the occurrence of one or more faults or failures. Fault tolerance is attained through the use of information, time, and physical redundancy.
Information redundancy uses additional information to detect, correct, or derive a bounded maximum of information in error, erasure, or unavailability. Time redundancy involves repeating actions otherwise incomplete without altering the system state. One example of time redundancy is "atomic transactions". An atomic transaction comprises a series of steps invoked by a process such that any interruption or failure to complete the series causes the system to return to its prior information state. Lastly, physical redundancy involves replacement of one portion of a physical computing, storage, or control layer with its performance clone.
Parenthetically, in this specification, the term "synchronous system" will be taken to mean a system having the property of always responding to a message within a known finite bound (T seconds). This includes time to process n repeat requests. Also, the term's "disk storage device", "direct access storage device", and the acronym DASD are used synonymously.
Aspects of Hierarchical Demand/Response
Storage Subsystems and RAID 5 Arrays
In the period spanning 1970 through 1985, IBM developed large-scale multiprogramming, multitasking computers, S/360 and S/370 running under an MVS operating system. A description of the architecture and that of the attached storage subsystem may be found in Luiz et al., U.S. Pat. No. 4,207,609, "Method and Means for Path Independent Device Reservation and Reconnection in a Multi-CPU and Shared Device Access System", issued Jun. 10, 1980. Such systems were of the hierarchical and demand/responsive type. That is, an application running on the CPU would initiate read and write calls to the operating system. These calls were, in turn, passed to an input/output processor or its virtual equivalent (called a channel) within the CPU. The read or write requests and related accessing information would be passed to an external storage subsystem. The subsystem would responsively give only status (availability, completion, and fault) and pass the requested data to or from the CPU.
The architecture of hierarchical demand/response storage subsystems such as the IBM 3990/3390 Model 6 and the EMC Symmetrix 5500 is organized around a large cache with a DASD-based backing store. This means that read requests are satisfied from the cache. Otherwise, the data satisfying those requests are staged up from the DASDs to the cache. Write updates result in data being sent from the CPU to the cache or to a separate nonvolatile store (NVS), or both. This is the case with the IBM 3990 Model 6. The NVS stored data is then destaged or written out to the DASDs on a batched basis asynchronous to processing the write requests. The term "demand/response" connotes that a new request will not be accepted from a higher echelon until the last request is satisfied by a lower echelon, and a positive indication is made by the lower to the higher echelon.
In order to minimize reprogramming costs, applications executing on a CPU (S/390) and the attendant operating system (MVS) should communicate with invariant external storage architecture even though some components may change. Relatedly, the view of storage associated with an MVS operating system requires that data be variable length formatted (CKD) and stored on an external subsystem of attached disk drives (IBM 3390) at addresses identified by their disk drive cylinder, head, and sector location (CCHHSS). Requested variable length formatted data is staged and destaged between the CPU and the storage subsystem as so many IBM 3390 disk drive tracks worth of information.
It well appreciated that an improved disk storage facility can be attached to a subsystem if the new facility is emulation compatible with the unit it has replaced. Thus, a RAID 5 storage array of small disk drives can be substituted for a large disk drive provided there is electrical and logical interface compatibility. Illustratively, the IBM 3990 Model 6 storage control unit can attach an IBM 9394 RAID 5 array DASD and interact with it as if it were several IBM 3390 large disk drives. Data is staged and destaged to and from the RAID 5 array formatted as CKD formatted 3390 disk drive tracks. The RAID 5 array in turn will reformat the tracks as one or more fixed-block formatted strings and write them out to disk.
Active Fault Management
An active strategy in anticipation of fault, failure, and error would be to continuously monitor all data handling and component performance. Indeed, such systems are described in Glider et al., U.S. Pat. No. 5,214,778, "Resource Management in a Multiple Resource System", issued May 25, 1993, and in Idleman et. al., U.S. Pat. No. 5,274,645, "Disk Array System", issued Dec. 28, 1993.
Glider discloses a method and means for managing both subsystem control code (CC) and an active fault management system (FMS) competing for a disk-based storage subsystem resource access. In Glider, a subsystem uses resource availability states as semaphores to ensure serialization where the FMS and the CC compete for access to the same resource. Significantly, the subsystem requires continuous availability monitoring for all resources for any changes.
Idleman describes a storage subsystem having a pair of two-level, cross-connected controllers providing a first and second failure-independent path to each DASD in a plurality of RAID 3 arrays of DASDs. Data is "striped" to support a parallel read or a parallel write across N+P+Q DASDs, where P and Q are redundancy bytes calculated over the N data bytes. That is, data is moved (parallel read or write) between controllers and a RAID 3 array using on-the-fly transverse redundancy error detection/correction and any-to-any switching between N+P+Q sources and sinks. As with prior art RAID 3, the redundancy blocks are bound to designated redundancy DASDs.
Passive Fault Management
In contrast to the Glider and Idleman references, a passive strategy can be used in a hierarchical, demand-responsive DASD storage subsystem exemplified by the IBM 3990/3390 Model 6. In a word, rather than hunt for fault or failure, the fault management is reactive. That is, the storage subsystem system relies on the presence of at least two failure-independent paths to a data storage location and the invocation of data recovery procedures (DRPs). The DRPs are invoked only upon the detection of error, fault, or failure in signals and data as they are read back or staged from a storage location.
Illustratively, a distorted modulated signal readback from a DASD track over a multibyte extent might cause a pointer to be generated at a signal processing level. It might also appear as a nonzero syndrome set at the ECC digital string reading level. At this point, an FMS would invoke DRPs to resolve the situation. Recovery actions might assume any one of a set of nested causes. The recovery actions themselves might range from a repetition of the read operation with or without a performance adjustment. For example, if the track/head misregistration was an assumed cause, then adjusting the head position relative to the track might be required. On the other hand, if thermal asperities were the assumed burst error cause, then ECC recovery from the syndrome set and the generated pointer might be the DRP of choice, etc.
Subsystem Complexity and Premature
Termination of Recovery Actions
Where a hierarchical demand/response storage system attaches one or more RAID 5 DASD arrays in addition or instead of conventional DASDs, the likelihood of a RAID 5 array becoming incapacitated by a single storage element (HDD) failure resulting in system failure is remote. This derives from the fact that RAID 5 arrays have sufficient information and physical redundancy to fault tolerate at least one failure. This is also the case for even RAID 1 (mirrored pairs of IBM 3390 DASDs) and RAID 3 or RAID 4 array configurations.
In RAID 5 as described in Clark et al., U.S. Pat. No. 4,761,785, "Parity Spreading to Enhance Storage Access", issued Aug. 2, 1988, a parity group of n-1 fixed-size data blocks plus a parity block are written over n DASDs. The blocks of the parity groups are spread such that no single DASD has two blocks from the same parity group and no DASD has all of the parity blocks written thereon. In the event that a single DASD should fail, then the RAID 5 array can laboriously recover data from a referenced parity group by logically combining n-1 blocks from the remaining DASDs. Any additional DASD failure would result in a permanent failure for the array. Thus, restoration of both fault tolerance and reasonable response time requires rebuilding the data stored on the failed DASD and writing out to a spare DASD within the array. But the time required for rebuilding data on a spare varies under conditions of load on the remaining DASDs. This fact is well articulated in Ng et. al., U.S. Pat. No. 5,278,838, "Recovery from Errors in a Redundant Array of Disk Drives", issued Jan. 11, 1994.
Passive fault management has heretofore been designed to resolve well-defined faults or errors within relatively narrow bounds. For instance, if j repeated read accesses of a given DASD yields j repeated ECC errors over a variety of DRPs, then the DASD may be declared dead, i.e., treated as a failure. However, complex devices such as a RAID 5 array of small DASDs substituting for a single large DASD or admixed with them is unlikely to appear to the host or 3990 SCU as a hard disk failure. This means that the inflexible mode of status reporting and handling is more likely to result in frequent and premature termination of host-level applications. These are a subsystem reporting a device as having failed when it in fact did not, or correlatively reporting a device or operation as being successful when in fact it had either failed or was aborted.
SUMMARY OF THE INVENTION
It is accordingly an object of this invention to devise a method and means for flexibly scheduling the report to a host CPU of fault and error conditions detected in an attached hierarchical demand/responsive storage subsystem in order to minimize premature terminations of applications and other host-based catastrophic actions.
It is a related object that said method and means facilitate such flexible scheduling in a storage subsystem having a diverse attachment of storage elements or devices such as RAID arrays and stand-alone DASDs.
It is yet another object that said method and means operably perform even where the subsystem has significantly different ways of responding to error, fault, and failure conditions.
It was unexpectedly observed that if the subsystem, upon the occurrence of fault or failure, provided a long device busy signal to the host for up to a finite maximum duration and isolated the storage device from any host inquiry, then the variable duration data recovery procedures executed at the subsystem and device levels, especially those involving RAID 5 rebuild, could be executed. This would avoid premature declarations of hard faults, failures, and errors.
Restated, the foregoing objects are believed satisfied by a method and means for detecting and correcting a defective operating state or condition of a hierarchical demand/responsive storage subsystem attaching a host CPU. The subsystem includes a plurality of cyclic, tracked storage devices, an interrupt-driven, task-switched control logic, and circuits responsive to the control logic for forming at least one path of a set of paths coupling the host to at least one device. The host enqueues one or more read and write requests against the subsystem. Responsively, the subsystem control logic interprets each request and establishes a path to an addressed storage device.
The method steps of the invention include detecting any anomaly in the read back or staging of data from the device and executing a retry of the counterpart request by active or passive querying of said addressed device. In the event that the detected anomaly persists, a long busy status signal is presented to the host CPU by the control logic. In this regard, the long busy signal is an indication that the counterpart request has yet to be completed by the subsystem. Next, access to the device is inhibited by the control logic for no more than a predetermined time interval. The method then ascertains whether the inhibited device has returned to an operational state. In the event the detected anomaly is resolved, an attention interrupt is set in the control logic by the device and the device long busy signal is terminated in the host CPU by the control logic. In the event that the time interval has been exceeded and the anomaly is not resolved, one or more data recovery procedures are invoked, including resetting the device by the control logic. Since the device has been driven into a final state, its status is then reported to the host CPU and the next request processed.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 shows a logical block diagram of an IBM 3990/3390 illustrative of a hierarchical, demand/responsive storage subsystem.
FIG. 2 depicts the subsystem of FIG. 1 but is modified to set out the attachment of a RAID 5 DASD array as a logical 3390 DASD in addition to the attachment of real 3390 DASDs.
FIG. 3 illustrates the method of the invention as it initially responds to the detection of any anomaly in the read back or staging of data from a storage device whether a single large device or as the logical equivalent formed from an array of small devices.
FIG. 4 sets forth the method of the invention after a determination that the error is not one correctable after retry and only one path to the device path is available.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to FIG. 1, there is shown a functional block diagram depiction of the IBM 3990/3390 Disk Storage Subsystem exemplifying a host-attached, hierarchical, demand/response storage subsystem. This subsystem is shown driven from first and second multiprogramming, multitasking hosts CPU 1 and 3, such as an IBM System/390 running under the IBM MVS operating system. The subsystem is designed such that data stored on any of the DASD storage devices 37, 39, 41, and 43 can be accessed over any one of at least two failure-independent paths from either one of the CPU's 1 or 3. The system as shown provides four failure-independent paths. Illustratively, data on devices 37 or 39 can be reached via 3390 controller 33 over any one of paths 21, 23, 25, or 27. The same holds for data stored on devices 41 or 43 via controller 35. A full description of this principle is to be found in the aforementioned U.S. Pat. No. 4,207,609, herein incorporated by reference.
The 3990 storage control unit consists of at least two storage directors 17 and 19. These are microprocessors and attendant local memory and related circuitry (not shown) for interpreting control information and data from the CPUs, establishing logical and physical paths to the storage devices, and managing fault and data recovery at the subsystem level. The read and write transfer directions are separately tuned. That is, read referencing is first made to cache 29, and read misses causes data tracks to be staged from the devices as backing stores. Write referencing either as a format write or an update write is made in the form of track transfers from the host to a nonvolatile store 31. From NVS 31, it is destaged to the devices through their sundry controllers.
Typically, an application executing on a host 1 or 3 requests to read a file, write a file, or update a file. These files are ordinarily stored on a large bulk 3990/3390 DASD storage subsystem 6. The MVS host (S/390) is responsive to any read or write call from the application by invoking an access method. An access method, such as VSAM, is a portion of the OS for forming an encapsulated message containing any requested action. This message is sent to an input/output (I/O) portion of the host, and ultimately the storage subsystem. Typically, the message includes the storage action desired, the storage location, and the data object and descriptor, if any. This "message" is turned over to a virtual processor (denominated a logical channel). The function of the logical channel is to send the message to the storage subsystem over a physical path connection (channels 5, 7, 9, 11). The storage subsystem control logic (director 17 or 19) then interprets the commands. First, a path to the designated storage device is established and passes the interpreted/accessing commands and data object to the storage device location on a real time or deferred basis. The sequence of commands is denominated "channel command words" (CCWs). It should be appreciated that the storage device may be either "logical" or "real". If the device is "logical", then device logic at the interface will map the access commands and the data object into a form consistent with the arrangement of real devices. Thus, a RAID 5 array of small DASDs substitutes for one or more IBM 3390 large DASDs.
The "access method" portion of the MVS operating system, when processing data objects in the form of variable length ECKD records, also will ascertain either a "new address" or an old (update in place) address. The access method assumes that external storage includes actual physical DASDs, etc. devices. It generates addresses on a DASD device, cylinder, head, and record (CCHHRR) basis. Significantly, the data objects are ordinarily aggregated on a 3380/3390 DASD track basis. That is, when an application requests one or more records, the access method determines what would be an efficient unit of staging, i.e., record staging or track staging between the S/390 and the 3990 SCU. Accordingly, the access method modifies the CCW chain and address extent occasionally from a track to a record. In turn, the logical channel will cause a string of CCWs, together with "track-formatted" data, to be destaged to a 3990 storage control unit (SCU). An IBM 3990 storage control unit (SCU) "interprets" the CCWs and batches the writes in the nonvolatile store 31 (NV write buffer) for later destaging to one or more 3390 logical or physical DASDs 37, 39, 41, 43. If a track is written out to a real 3390 DASD, then it will perform ECC processing as discussed subsequently. Originally, an access method comprised a set of protocols for moving data between a host main memory and physical input/output devices. However, today it is merely a mapping to a logical view of storage, some of which may be physical storage.
Referring now to FIG. 2, there is depicted the subsystem of FIG. 1 but modified to set out the attachment of a RAID 5 DASD array 213 as a logical 3390 DASD, in addition to the attachment of real 3390 DASDs. In this regard, the IBM 3990 SCU Model 6 (FIG. 2/6) utilizes a large cache (up to 2 gigabytes) (FIG. 2/29). The data is always staged and destaged in the form of 3380/3390 tracks. This occurs when staging data between a plurality of logical (FIG. 2/213) or real 3390 DASDs (FIG. 2/35, 41, 43) and the 3990 cache (FIG. 2/29) and destaging data between an NV write buffer (FIG. 2/31) and the logical or real 3390 DASDs.
When track-formatted data is written out to the DASDs at the physical device, an ECC check byte is calculated over any destaged tracks and stored with the track. Upon any subsequent read access, an ECC calculation over the staged tracks is again made and a comparison match between the stored values and the calculated values. Any mismatch is indicative of error. Restated, upon read back or staging of the data from a DASD, detection of any nonzero syndrome is an indication of random or burst error in the data.
Referring again to FIG. 2, there is depicted a RAID 5 array 213 of small DASDs 211 attached to the control logic 17, 19 of the IBM 3990 storage control unit 6 over the plurality of paths 21, 23, 25, and 27 via device adapters (DAs) 201. One implementation of RAID 5 arrays is to be found in the IBM RAMAC Array DASD attaching one or more Enterprise System (S/390) ECKD channels through an IBM 3990 Model 3 or 6 storage control unit. The RAMAC Array DASD comprises a rack with a capacity between 2 to 16 drawers. Each drawer 213 includes four disk drives HDD0-HDD3, cooling fans, control processor 207, ancillary processors 203, and a nonvolatile drawer cache 205. It is configured as a track staging/destaging to three DASDs' worth of data space and one DASD's worth of parity in a RAID 5 DASD array. Each drawer emulates between two to eight IBM 3390 Model 3 volumes.
Functionally, the DAs 201 provide electrical and signal coupling between the control logic 17 and 19 and one or more RAID 5 drawers. As tracks are staged and destaged through this interface, they are converted from variable length CKD format to fixed-block length FBA format by the ancillary processors 203. In this regard, drawer cache 205 is the primary assembly and disassembly point for the blocking and reblocking of data, the computation of a parity block, and the reconstruction of blocks from an unavailable array of DASDs. In this embodiment, three DASDs are used for storing parity groups, and the fourth DASD operates as a hot spare. If a dynamic (hot) sparing feature is used, then the spare must be defined or configured a' priori. Space among the three operational arrays is distributed such that there exists two DASDs' worth of data space and one DASD's worth of parity space. It should be pointed out that the HDDs 211, the cache 205, and the processors 203 and 207 communicate over an SCSI-managed bus 209. Thus, the accessing and movement of data across the bus between the HDDs 211 and the cache 205 is closer to an asynchronous message-type interface.
Since passive fault management is used, it should be pointed out that ECC correction is applied only to data as a serial stream read or staged from a given array storage device. The parity block is used only in recovery mode to reconstruct data from an unavailable or failed one of the array DASDs. The recovery takes the form of computing the unavailable block by a modulo 2 addition of the n-1 remaining blocks of a given parity group. Although DASDs in the array can suffer both hard as well as Byzantine faults, the worst case is to treat an array DASD as a hard failure and rewrite the data on the spare DASD, time permitting.
Referring now to FIG. 3, there is shown the initial subsystem response to the detection of any anomaly in the read back or staging of data from a storage device, whether a single large device or as the logical equivalent formed from an array of small devices. More particularly, the IBM 3990 senses or detects an error or performance anomaly in step 301. This occurs either by control logic 17, 19 polling any of the storage devices (FIG. 2/213, 41, or 43), any of the devices setting an interrupt in the control logic, or failure to respond. Relatedly, steps 303-315 ascertain whether the detected anomaly is of a type or nature for which the device long busy recovery procedure 315 should be invoked. Thus, if the anomaly is a hard device failure or a hard failure in the only path to a device as indicated in step 303, then a long busy recovery process of step 315 will be invoked. Otherwise, as two or more paths to the device associated with the anomaly are operable, then resolution will be attempted without invoking step 315. Clearly, steps 305, 307, and 311 determine whether such multiple paths to a device are available. Parenthetically, for purposes of the method of this invention, a RAID 5 array is considered as a single device. As mentioned in the discussion of the embodiment in FIGS. 1 and 2, a hierarchical subsystem of the IBM 3990/3390 type includes at least two failure-independent paths to each device. However, since paths may be unavailable for a variety of reasons on a permanent or intermittent basis, such a test is necessary for efficient subsystem use of fault management resources.
Referring now to FIG. 4, there is shown the method of the invention after a determination that the error is not one correctable after retry and only one path to the device path is available. The correction may involve a variable duration recovery time. The recovery starts in step 315 with the presentation of a device long busy status signal to the host CPU 1, 3 by the control logic 17, 19. In steps 401 and 403. the control unit isolates the device by inhibiting two forms of access through suspension of read and write requests (step 401) and pinning the destaging of tracks in NVS 31 for up to a maximum predetermined duration. In current practice, a maximum time interval/delay in the order of 90 seconds has proven effective. The control in step 405 passes to the device for invoking one or more recovery procedures for resolving the anomaly. It should also be appreciated that when a device operates in a recovery mode, it operates from a linear list of nested DRPs ordered on statistical assumptions as to causes of the anomaly.
The recovery procedures at the device level include correcting an error or erasure in a binary data stream of linear cyclic codewords using only nonzero syndromes, an erasure locator polynomial, and pointers. Also, the list of DRPs may include conditional branches to DRPs otherwise lower in list order such as where detection of a possible erasure or burst sets an interrupt in the device microprocessor.
While the invention has been described with respect to an illustrative embodiment thereof, it will be understood that various changes may be made in the method and means herein described without departing from the scope and teaching of the invention. Accordingly, the described embodiment is to be considered merely exemplary and the invention is not to be limited except as specified in the attached claims. | A method and means within a hierarchical, demand/response DASD subsystem of the passive fault management type in which, upon the occurrence of fault, error, or erasure, a long device busy signal of finite duration is provided to a host CPU. Any DASD storage device subject to the anomaly is isolated from any host inquiry during this interval. These measures permit retry or other recovery procedures to be implemented transparent to the host and the executing application. This avoids premature declarations of faults, errors, or erasures and consequent host application aborts and other catastrophic measures. If the detected anomaly is not resolved within the allotted time, then other data recovery procedures can be invoked including device reset, the status reported to the host, and the next request processed. | 6 |
CROSS-REFERENCE TO RELATED APPLICATIONS
Not Applicable.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
Not Applicable.
INCORPORATION BY REFERENCE OF MATERIAL SUBMITTED ON A COMPACT DISC
Not Applicable.
COPYRIGHTED MATERIAL
Not Applicable.
BACKGROUND OF THE INVENTION
1. Field of the Invention (Technical Field)
The present invention relates to a single stage micro- or mini-sized valve comprising a direct drive actuator, capable of rapid opening/closing transient time, and capable of working at high frequency.
2. Description of Related Art
For some applications, a rapid high-flow valve is necessary, such as for steering space vehicles and controlling equipment that requires a fast response. Conventional fluid valves are usually either fast but low-flow or slow and high-flow. One possibility is to use multistage valves with at least two stages. Unfortunately this class of valves solves the frequency problem by operating on the slave valve (pilot stage) at reduced flow and therefore higher frequency. Under these conditions the opening and closing transient time suffers an intrinsic delay that even in the case of two stages can severely limit the final obtainable frequency, as in U.S. Pat. No. 6,830,229, to Wetzel, et al.
The present invention achieves maximum operating speed and maximum frequency by using a single stage valve controlled by a fast direct-coupled actuator. An appropriate such actuator is disclosed in U.S. Pat. No. 6,774,539, to Guida.
BRIEF SUMMARY OF THE INVENTION
The present invention is of a valve and concomitant method of controlling flow of a fluid with a valve, comprising: isolating a fluid path from a valve stem with a diaphragm in a valve body; blocking the fluid path with a plunger having a stroke of less than approximately 500 micrometers; driving the plunger with an actuator; and operating the valve at a frequency of at least approximately 20 Hz but with a flow of at least approximately 5.0E-04 kg/sec. In the preferred embodiment, the valve provides a flow of at least approximately 1.0E-03 kg/sec. A dome shaped recess within the body accommodates the diaphragm, is conformal to the shape of the diaphragm when in an open state, and has a depth of approximately 50% of total diaphragm swing. A stem conditioner may be employed to limit down stroke of the plunger, and may be a spring, one or more valves controlling recovery time, and/or a stem with an upper and lower portion capable of telescoping operation (most preferably including a smaller valve operating only in one direction and a larger valve operating only in the other direction)
Objects, advantages and novel features, and further scope of applicability of the present invention will be set forth in part in the detailed description to follow, taken in conjunction with the accompanying drawings, and in part will become apparent to those skilled in the art upon examination of the following, or may be learned by practice of the invention. The objects and advantages of the invention may be realized and attained by means of the instrumentalities and combinations particularly pointed out in the appended claims.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
The accompanying drawings, which are incorporated into and form a part of the specification, illustrate one or more embodiments of the present invention and, together with the description, serve to explain the principles of the invention. The drawings are only for the purpose of illustrating one or more preferred embodiments of the invention and are not to be construed as limiting the invention. In the drawings:
FIG. 1 is a cross-section view of the entire valve of the invention;
FIG. 2 is a more detailed view of the bottom valve body;
FIG. 3 is a bottom block top view;
FIG. 4 is a top block cross-section view;
FIG. 5 is a cross-section view of the stroke length conditioner;
FIG. 6 is a cross-section view of the stroke speed conditioner;
FIG. 7 is an alternative embodiment of the conditioner; and
FIG. 8 is a cross-section view of the self-adjusting stem length device.
In the drawings, the following reference numerals are employed:
11 Bottom valve body 12 Top valve body 13 Valve inlet 14 Valve outlet Isolation diaphragm 16 Plunger 17 Valve seat 18 Stem 19 Stem conditioner 20 Actuator 21 Bottom block 22 Valve seat 23 Inlet port 24 Outlet port 25 Bottom inlet chamber 31 Bottom valve block 32 Flat valve seat 33 Valve inlet. 34 Inlet chamber 35 Seat step 41 Top valve block 42 Upper inlet chamber 43 Diaphragm positioning and holding recess 44 Isolation diaphragm 45 Dome shaped diaphragm stop. 46 Valve Stem 47 Stem access hole 48 Plunger 51 Plunger 52 Valve main body 53 Down stroke travel stopper 54 Valve upper body 55 Stem 56 Diaphragm 61 Conical spring 62 Top valve body 63 Stem spring collar 64 Stem 65 Plunger 66 Diaphragm conformal stop 67 Inlet chamber 71 Spring 72 Stem 73 Plunger 81 Container 82 Fluid 83 Piston 84 Valve stem 85 Conical Spring 86 One-way fast port 87 One way slow port 88 Stem aligner and stopper 89 Stroke length adjust gap
DETAILED DESCRIPTION OF THE INVENTION
The present invention is of a valve comprising a minimum of basic parts, thereby rendering it simple, reliable, and robust. The valve and its preferred components are illustrated in FIG. 1 . Main body 11 serves as support to hold all other parts. Top plate 12 operates as the valve cover. Diaphragm 15 isolates the fluid path from the valve stem. Plunger 16 physically blocks the flow in conjunction with valve seat 17 , stem 18 operates the plunger 16 , actuator 20 drives the stem 18 according to the valve specifications. Stem stroke conditioner 19 can be included to match the system requirements and/or improve performance.
FIG. 2 is a cross-section of main body 11 , with 21 being the bulk valve body made of metal, ceramic, or composed material depending on the operation and performance required. Built into the body 21 is an inlet hole 23 for the incoming fluid to be controlled, and an outlet channel 24 that serves as the fluid exit. Concentrically to inlet port 23 is plunger seat 22 , and a chamber 25 machined in the body 21 for the double function of creating the fluid path once the valve is in open position, and permitting the motion of plunger 16 and diaphragm 15 . The chamber should be as small as possible to avoid time delay during the valve opening, but large enough to ensure an unrestricted fluid flow path. The valve seat can be shaped as round, conical, or flat depending on the application. A round seat as illustrated in 22 has the advantage of self alignment and providing a high pressure contact point.
FIG. 3 is a cross-section of a flat shaped valve seat, where 31 is the main valve body, 33 is the valve inlet, 34 the valve outlet, 35 is a step defining the contact surface between plunger and seat which in turn determines the closing pressure capability of the valve. (Pressure=Force/Area). 32 is the flat sealing area of the valve seat. The valve seat can be machined, cast in bulk, or added as an insert, in which case it is interchangeable.
The valve top body illustrated in FIG. 4 comprises a bulk plate 41 in which there is a trough hole 47 for stem 46 to reach plunger 48 . A dome shaped recess 45 accommodates diaphragm 44 during the opening cycle. The shape of dome 45 is designed to reduce excessive stress in the diaphragm by acting as a uniform stop. To do so it must be conformal to the diaphragm shape in the open condition. To reduce the diaphragm stress, the depth of dome 45 should be about 50% of the total diaphragm swing. A shallow step 43 can be machined to recess dome 45 for the purpose of self-aligning and position-retaining diaphragm 44 .
FIG. 5 shows one application of stem conditioner 19 . In this instance, stem 55 is provided with a hard stop 53 that limits the down stroke of plunger 55 by reaching top valve body 54 . This may be required to avoid damage to plunger 51 and seat 32 , or in the case of flat seat 32 without plunger, damage to diaphragm 56 .
FIG. 6 is another application of stem conditioner 19 . In this instance a spring 61 is placed between stop 63 and top valve body 62 , which has the effect of speeding up the opening of the valve in case of an unbalanced actuator action, or if so needed in special operations. Spring 61 can be cylindrical or, to reduce space, conical as in 61 . Obviously, this spring if positioned on the other end of the stem produces the opposite action (i.e., speeding up of the closing cycle).
Another important use of conditioner 19 is considered in FIG. 7 . In this instance spring 71 is located along stem 72 , with or without any stop, and provides a damping action by absorbing any excess down stroke otherwise applied directly to plunger 73 .
FIG. 8 shows a self-adjusting stroke amplitude application of a conditioning device 19 . In this instance spring 85 is placed inside a closed container 81 , which acts like a hydraulic damper of the same kind used with cars or door closing. Valve 87 , which controls the recovery time, is preferably sized in such a way as to recover only a small fraction of the stem length at a given frequency. The length of the stem is practically self adjusted during the first downward valve cycle because the extra length is reduced by means of upper stem portion 89 moving inside bottom stem portion 88 . This is a fast adjustment due to large one-way valve 86 . Successively during the up worth steam motion the spring 85 tries to expand back, but the amount of expansion is limited by small valve 87 preventing fluid 82 from returning to the upper part of the container 81 .
The overall operation of the valve of the invention is straightforward: actuator 20 keeps the valve closed by pushing on plunger 16 via stem 18 with or without the help of conditioner 19 . When actuator 20 retracts, the pressure of the fluid coming in through inlet 13 pushes upward first plunger 16 and then diaphragm 15 , permitting fluid flow through chamber 67 and out to valve outlet 14 . The stem conditioner is not necessary for the valves functioning, but may be employed to accommodate special valve applications. Plunger 16 can be conical, spherical or flat, in which case it can entirely be replaced by diaphragm 15 assuming that it can stand the compression stress imposed by stem 18 .
The present invention provides flow up to more then ten times greater than prior art valves operating at high frequency, i.e., >20 Hz. This provides the ability to closely match load requirements (maximum efficiency) if used in conjunction with a high pressure high speed actuator as discussed above Table 1 provides a comparison between a prior art fast valve (as disclosed in U.S. Pat. No. 6,830,229) and the valve of the present invention:
TABLE 1
Prior Art
Valve of the Present Invention
Valve
High Pres.
Long Stroke
Units
Actuator Force
5
2000
10
N
Pressure
1500
1309878
2911
K(Pa)
Stroke
40
40
377
μm
Orifice Diameter
2
2
3
mm
Orifice Area
3.14
3.14
7.07
mm 2
Flow area
0.251
0.251
3.553
mm 2
Flow
1.0E−04
>10X
>10X
kg/sec
Note: Frequency and flow are directly dependent. Moreover, the flow is a function of fluid density, fluid viscosity, and pressure, and therefore if the working conditions are not known it is difficult to specify exact valve performance. Only the ranges can be calculated.
In summary, the present invention provides the advantages of simple construction, small number of parts, relatively low fabrication cost, very high performance as to speed, pressure, temperature, and full flow path isolation, and the ability to customize performance.
Although the invention has been described in detail with particular reference to these preferred embodiments, other embodiments can achieve the same results. Variations and modifications of the present invention will be obvious to those skilled in the art and it is intended to cover in the appended claims all such modifications and equivalents. The entire disclosures of all references, applications, patents, and publications cited above are hereby incorporated by reference. | A valve and concomitant method of controlling flow of a fluid with a valve comprising isolating a fluid path from a valve stem with a diaphragm in a valve body, blocking the fluid path with a plunger having a stroke of less than approximately 500 micrometers, driving the plunger with an actuator, and operating the valve at a frequency of at least approximately 20 Hz but with a flow of at least approximately 5.0E-04 kg/sec. | 5 |
FIELD OF THE INVENTION
This invention relates to the viewing of data in multi-channel electronic acquisition instrument displays, and more particularly to a method of selectively processing a subset of acquired data for inclusion in a multi-channel electronic acquisition instrument display.
CROSS-REFERENCE TO RELATED APPLICATIONS
[Not applicable]
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH AND DEVELOPMENT
[Not applicable]
BACKGROUND OF THE INVENTION
Historically, users have been able to display a subset of the channels for which data was acquired, masking out the data associated with channels that are not presently of interest to the user. This form of data suppression selects which channels of data are of interest. Individual channels and groups of channels can be selected for display or hidden from view, according to user preference. These decisions can be made before or after data is acquired. Whenever these decisions are made, they serve to mask channels of data from view.
In the past the most common way to suppress samples is to reduce the number of samples stored in the instrument at the time data was acquired. This had the problem that if the operator needed more samples to evaluate he had to increase memory depth and re-acquire data. This is time consuming and expensive if the problem being analyzed is hard to reproduce.
Historically, other forms of filtering have also been available along the sample or time axis. The data filtering along this axis has been, in one manner or another, filtering in accordance with some sort of dependence on the data acquired. Individual bits are examined to determine if the sample is to be displayed or suppressed. This is known as “data qualification”, and it can be applied during the acquisition process or after the data is acquired. The latter is known as “post-processing”.
A more complex form of post-processing is “disassembly. Assembly is the conversion of microprocessor code, that language used by the programmer, into the specific patterns of 1's and 0's that are understood by a particular type of microprocessor. Disassembly is the reverse process, converting 1's and 0's used by the microprocessor back into assembly language that can be understood by the programmer. This process requires examining large amounts of acquired data and converting it to processor mnemonics.
A variety of data simplifications can be applied during the display of Disassembled data in the instrument. Hardware cycles can be suppressed, leaving only the software execution operations available in a clear and concentrated form. Program control flow strips out all samples except for those that caused a branch, subroutine call subroutine return or interrupt call or return during processor execution. Alternatively, only program subroutine entrance and exit cycles can be shown, creating an outline-like view of the software subroutines that have been executed.
“State-based” filtering is another form of general purpose filtering. The operator-supplied filter examines acquired data one sample at a time and controls, which samples are to be presented for display. (State machines generally examine the state of old data and new data and go to a corresponding next state.) State based filters are powerful tools, but they also require a lot of processing time to read and evaluate data before it can be displayed. This type of filter is known as “state-based” because each acquired sample is dealt with according to the prior data state as well as the current state data, much like a trigger state machine (or the generic state machine described above).
Over the years, as the price of memory has gone way down and the length of the data records captured by multi-channel electronic acquisition instruments has gone way up, relatively huge memory depths have become increasingly common. As acquisition memories become longer, more time consuming to acquire, and unwieldy to analyze, new methods for focusing operator attention into the most relevant portions of the data are increasingly valuable.
Ideally, a tool for accomplishing this filtering would not add overhead to the display process, as manipulating very large data records already requires a lot of time. It is expected that this filtering tool is used in conjunction with other types of filters. In other words, this data filter supplements other types of filters, rather than replacing them.
BRIEF SUMMARY OF THE INVENTION
In accordance with the present invention, arbitrary sets of samples may be suppressed from display and analysis. The resulting record may then be saved in its full form, i.e., unsuppressed and suppressed, or abbreviated, unsuppressed only, form. Such a record may also be retrieved and arbitrarily partially suppressed a second or third time, making a series of smaller and less complete acquisition histories. Each of these records may be saved with or without suppressed samples and may be later redisplayed, reliably showing those samples originally saved and their attributes, such as the time the sample was stored and its original sample number). Records saved without suppressed samples are permanently lost.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS
FIG. 1 is a conceptual illustration of how a virtual view is constructed from portions of the complete acquired memory record.
FIG. 2 is an illustration of the virtual view management dialog box.
FIG. 3 is a waveform (time axis) overview of a portion of the virtual view.
FIG. 4 is a listing (state table) perspective on a portion of a virtual view.
DETAILED DESCRIPTION OF THE INVENTION
Sample suppression according to the present invention gives the operator arbitrary control over which instrument samples are available for display and analysis. This control may be thought of as “arbitrary” because the operator can pick any instrument sample and decide to display (show) or suppress (hide) that sample. This choice is independent of whether the sample is associated with hardware or software activity, or whether it occurs (or doesn't) in connection with any other criteria.
This type of sample suppression permits the operator to be the “judge”, determining which samples will be part of the display and which will be suppressed. This is useful because not all samples collected in a particular acquisition are important and worth analysis. Moreover, the perceived value and importance of retained samples can change with different levels of scrutiny. Thus, the as the operator learns more about his acquired and saved data, further suppression decisions may be desired as part of the continuing analysis process.
FIG. 1 is a conceptual illustration of how a virtual view is constructed from portions of the acquired memory. Samples of data (voltage level, state value, time of measurement, etc.) that pass through a sample suppression process can best be described as a “virtual view” or “virtual image”. All data windows display their data from this virtual view. The user has controls that allow samples (individual or blocks of samples) to be added or removed from this image without acquiring new data. This provides the operator with complete control over which samples to display, analyze and eventually save to disk.
The number and size of these blocks of samples is limited only by the number of samples originally acquired. Each sample of Instrument Memory can only appear once in the virtual image. The order of samples in the virtual image must be monotonic order (i.e. actual sample 5 cannot appear before actual sample 4 in the virtual image).
Data windows receive samples from the instrument's virtual image. As in this example each view can display the same or different portions of the virtual view. If the operator adds instrument samples to the virtual view these will be displayed by all instrument views.
Referring next to FIG. 2, there is shown an illustration of the virtual view management dialog box. This dialog box allows the operator to control how much data is initially delivered to the data view. The instrument acquires and fills all memory, but only the samples so defined in this dialog box are displayed or analyzed. After data acquisition the operator can, at his discretion, show or suppress more samples using direct manipulation through the listing or waveform views.
FIG. 3 is a waveform (time axis) overview of a portion of the virtual view. Where data has been suppressed, dashed lines mark the location of the data that is missing. All remaining samples are displayed in typical timing diagram format. Suppression of samples does not compress the display horizontally, as doing so would change the time relationship of data on the screen, violating the operator's expectations. By removing data that is not relevant, the user can focus on those samples that are most relevant.
Referring now to FIG. 4, this is an illustration of is a listing (state table) perspective on a portion of a virtual view. The gray horizontal lines in the sample column show where gaps are located due to sample suppression. Through the use of suppression the user can directly control how much data is visible and thereby concentrate on only the data that is relevant to his measurement needs. Notice that this display removes the suppressed samples completely and thereby allows the display to be compressed. This consolidation helps the operator focus in on the important part of the data. The operator can show or suppress samples through a waveform or listing window using direct manipulation of controls, such as a mouse or keyboard. The user selects a sample or block of samples, and then indicates whether they are to be shown or suppressed. Returning then to FIG. 4 and the sample above, the operator can see those acquired samples that are visible (e.g., samples 16334 through 16345 and 16360 through 16369 ) and those which are suppressed (Samples 0 through 16333 , 16346 through 16359 ). In this way the listing window gives very detailed information on how sample suppression currently effects the display of data.
Sample suppression can be added to other forms of data filters (state based, disassemblers, data qualification, etc.). This gives the operator control over how much of the data in the instrument memory is to be analyzed by other software filters. This allows the operator to scroll back and forth through the data during the analysis process much faster because these other software analysis tools no longer have to spend time analyzing those areas of memory that have been suppressed. Any suppressed samples can later be recovered and added back into the analysis process if desired. The ability to unsuppress samples is very important capability. However, saving without suppressed samples causes them to be permanently deleted. The user can no longer un-suppress those samples.
The beauty of this approach is that the process of suppressing data does not have to be a careful, or even thoughtful, process, based on knowledge of the content of the data. Instead, data can be arbitrarily manipulated after an acquisition and before the operator has meaningful understanding of which data is which. Almost all filters in the past have been designed to evaluate a very specific kind of data. They operate by examining data stored by the instrument, according to acquisition and display algorithms. These tools tend to be application specific and therefore do not work in all circumstances. Even a general purpose state-based filter works by examining data samples and their context.
The instrument can keep track of the virtual view using a bitmap or some other means, such as a list of samples or sample ranges. A bit map index is the functional equivalent of adding a single bit data extension to the existing memory contents. These bits can have either sense, signifying either data to be suppressed or data to be displayed and analyzed. This bit map approach is most efficient when the number of fragmentary (range of samples) is expected to be large. A list can contain a pair of sample numbers identifying a range of samples to show or suppress. Such a list-based approach is more efficient when the number of fragments (ranges of samples) is expected to be small.
Alternatively, a separate address list can identify samples to be suppressed and samples to be displayed, each address acting as either an entry point or exit point with respect to the active or suppressed samples. Alternatively, the virtual view can be maintained via a dual interleaved list of sample numbers or identifying addresses. One set signifies starting points of suppressed or displayed data, while the other set signifies starting points for the complementary type of location (displayed or suppressed). It should be noted that a sample, the item pointed to by a sample number or sample address, may contain any instrument measurement result, such as state value, voltage value, or time value, and any other auxiliary information associated with that sample.
One optional feature of sample suppression is the ability to save only those samples in the virtual view. When the operator opens and displays this file the product should know that the missing samples are no longer available for display. It should also allow all remaining samples to be suppressed or shown without restriction. This requires that the list keep track of which suppressed samples are currently saved and which are not. This can be done by providing a property in the list indicating whether the sample is currently stored and available for display.
In a preferred embodiment of this filter, there are some properties of the acquired data that it would be best not to change. For instance, usually, samples should not be renumbered. Each sample has a unique number that identifies its original storage location in acquisition memory, and it is best not to change that. Also, the display order will generally not be changed. Changing the sample suppression list should generally never cause the display order of two samples to be different. There may be cases where processing by another algorithm (disassembler or state based filter) overrides this general rule. Changes in sample suppression or inclusion status should not cause the same sample to appear twice on the display.
Usually there is one single suppression list per instrument. In that type of implementation, all data windows display data that pass through this common suppression filter. Another possibility is to provide a separate suppression filter for each data window. The operator then has a choice of several different displays that show different portions of the acquired data.
While a preferred embodiment of the present invention has been shown and described, it will be apparent to those skilled in the art that many changes and modifications may be made without departing from the invention in its broader aspects. The claims that follow are therefore intended to cover all such modifications as are permitted by the patent laws of any countries in which this patent is granted. | Arbitrary sets of samples may be suppressed from display and analysis. The resulting record may then be saved in its abbreviated form or discarded. Such a record may also be retrieved and arbitrarily partially suppressed a second or third time, making a series of smaller and less complete acquisition histories. Each of these records may be saved with or without suppressed samples and may be later redisplayed reliably showing those samples originally saved. | 6 |
CONTINUING APPLICATION DATA
[0001] The present application claims priority to U.S. provisional application Ser. No. 60/812,078, filed on Jun. 9, 2006, and incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to sodium channel blockers possessing beta-adrenergic receptor agonist activity. The present invention also includes a variety of methods of treatment using these inventive sodium channel blockers/beta-adrenergic receptor agonists.
[0004] 2. Description of the Background
[0005] The mucosal surfaces at the interface between the environment and the body have evolved a number of “innate defenses”, i.e., protective mechanisms. A principal form of such an innate defense is to cleanse these surfaces with liquid. Typically, the quantity of the liquid layer on a mucosal surface reflects the balance between epithelial liquid secretion, often reflecting anion (Cl − and/or HCO 3 − ) secretion coupled with water (and a cation counter-ion), and epithelial liquid absorption, often reflecting Na + absorption, coupled with water and counter anion (Cl − and/or HCO 3 − ). Many diseases of mucosal surfaces are caused by too little protective liquid on those mucosal surfaces created by an imbalance between secretion (too little) and absorption (relatively too much). The defective salt transport processes that characterize these mucosal dysfunctions reside in the epithelial layer of the mucosal surface.
[0006] One approach to replenish the protective liquid layer on mucosal surfaces is to “re-balance” the system by blocking Na + channel and liquid absorption and simultaneously activating beta-adrenergic receptors thereby causing liquid secretion. The epithelial protein that mediates the rate-limiting step of Na + and liquid absorption is the epithelial Na + channel (ENaC). ENaC and beta-adrenergic receptors are positioned on the apical surface of the epithelium, i.e. the mucosal surface-extermal environment interface. Therefore, to inhibit ENaC mediated Na + and liquid absorption, an ENaC blocker of the amiloride class (which blocks from the extracellular domain of ENaC) must be delivered to the mucosal surface and, importantly, be maintained at this site, to achieve therapeutic utility. The present invention describes diseases characterized by too little liquid on mucosal surfaces and “topical” sodium channel blockers containing beta-adrenergic receptor agonist activity designed to exhibit the increased potency, reduced mucosal absorption, and slow dissociation (“unbinding” or detachment) from ENaC and the beta-adrenergic receptor required for therapy of these diseases.
[0007] Chronic bronchitis (CB), including the most common lethal genetic form of chronic bronchitis, cystic fibrosis (CF), are diseases that reflect the body's failure to clear mucus normally from the lungs, which ultimately produces chronic airways infection. In the normal lung, the primary defense against chronic intrapulmonary airways infection (chronic bronchitis) is mediated by the continuous clearance of mucus from bronchial airway surfaces. This function in health subjects effectively removes from the lung potentially noxious toxins and pathogens. Recent data indicate that the initiating problem, i.e., the “basic defect,” in both CB and CF is the failure to clear mucus from airway surfaces. The failure to clear mucus reflects an imbalance between the amount of liquid and mucin on airway surfaces. This “airway surface liquid” (ASL) is primarily composed of salt and water in proportions similar to plasma (i.e., isotonic). Mucin macromolecules are organized into a well defined “mucus layer” which normally traps inhaled bacteria and are transported out of the lung via the actions of cilia which beat in a watery, low viscosity solution termed the “periciliary liquid” (PCL). In the disease state, there is an imbalance in the quantities of mucus and ASL on airway surfaces. This imbalance results in a relative reduction in ASL which leads to mucus concentration, a reduction in the lubricant activity of the PCL, and a failure to clear mucus via ciliary activity to the mouth. The reduction in mechanical clearance of mucus from the lung leads to chronic bacterial colonization of mucus adherent to airway surfaces. It is the chronic retention of bacteria, the failure of local antimicrobial substances to kill mucus-entrapped bacteria on a chronic basis, and the consequent chronic inflammatory responses of the body to this type of surface infection, that lead to the syndromes of CB and CF.
[0008] The current afflicted population in the U.S. is 12,000,000 patients with the acquired (primarily from cigarette smoke exposure) form of chronic bronchitis and approximately 30,000 patients with the genetic form, cystic fibrosis. Approximately equal numbers of both populations are present in Europe. In Asia, there is little CF but the incidence of CB is high and, like the rest of the world, is increasing.
[0009] There is currently a large, unmet medical need for products that specifically treat CB and CF at the level of the basic defect that cause these diseases. The current therapies for chronic bronchitis and cystic fibrosis focus on treating the symptoms and/or the late effects of these diseases. Thus, for chronic bronchitis, inhaled β-agonists, steroids, anti-cholinergic agents, and oral theophyllines and phosphodiesterase inhibitors are all in current use. However, none of these drugs alone effectively treat the fundamental problem of the failure to clear mucus from the lung. Similarly, in cystic fibrosis, the same spectrum of pharmacologic agents are used. These strategies have been complemented by more recent strategies designed to clear the CF lung of the DNA (“Pulmozyme”; Genentech) that has been deposited in the lung by neutrophils that have futilely attempted to kill the bacteria that grow in adherent mucus masses and through the use of inhaled antibiotics (e.g. “TOBI”) designed to augment the lungs' own killing mechanisms to rid the adherent mucus plaques of bacteria. A general principle of the body is that if the initiating lesion is not treated, in this case mucus retention/obstruction, bacterial infections become chronic and increasingly refractory to antimicrobial therapy. Thus, a major unmet therapeutic need for both CB and CF lung diseases is an effective means of re-hydrating airway mucus (i.e., restoring/expanding the volume of the ASL) and promoting its clearance, with bacteria, from the lung.
[0010] R. C. Boucher, in U.S. Pat. No. 6,264,975, describes the use of pyrazinoylguanidine sodium channel blockers for hydrating mucosal surfaces. These compounds, typified by the well-known diuretics amiloride, benzamil, and phenamil, are effective. However, these compounds suffer from the significant disadvantage that they are (1) relatively impotent, which is important because the mass of drug that can be inhaled by the lung is limited; (2) rapidly absorbed, which limits the half-life of the drug on the mucosal surface; and (3) are freely dissociable from ENaC. The sum of these disadvantages embodied in these well known diurectics produces compounds with insufficient potency and/or effective half-life on mucosal surfaces to have therapeutic benefit for hydrating mucosal surfaces.
[0011] Clearly, what is needed are drugs that are more effective at restoring the clearance of mucus from the lungs of patients with CB/CF. The value of these new therapies will be reflected in improvements in the quality and duration of life for both the CF and the CB populations.
[0012] Other mucosal surfaces in and on the body exhibit subtle differences in the normal physiology of the protective surface liquids on their surfaces but the pathophysiology of disease reflects a common theme, i.e., too little protective surface liquid. For example, in xerostomia (dry mouth) the oral cavity is depleted of liquid due to a failure of the parotid sublingual and submandibular glands to secrete liquid despite continued Na + (ENaC) transport mediated liquid absorption from the oral cavity. Similarly, keratoconjunctivitis sira (dry eye) is caused by failure of lacrimal glands to secrete liquid in the face of continued Na + dependent liquid absorption on conjunctional surfaces. In rhinosinusitis, there is an imbalance, as in CB, between mucin secretion and relative ASL depletion. Finally, in the gastrointestinal tract, failure to secrete Cl— (and liquid) in the proximal small intestine, combined with increased Na + (and liquid) absorption in the terminal ileum leads to the distal intestinal obstruction syndrome (DIOS). In older patients, excessive Na + (and volume) absorption in the descending colon produces chronic constipation and diverticulitis.
SUMMARY OF THE INVENTION
[0013] It is an object of the present invention to provide compounds that have both sodium channel blocking activity and beta-adrenergic receptor agonist activity in the same molecule.
[0014] It is an object of the present invention to provide compounds that are more potent and/or absorbed less rapidly from mucosal surfaces, and/or are less reversible as compared to known compounds.
[0015] It is another aspect of the present invention to provide compounds that are more potent and/or absorbed less rapidly and/or exhibit less reversibility, as compared to compounds such as amilorde, benzamil, and phenamil. Therefore, the compounds will give a prolonged pharmacodynamic half-life on mucosal surfaces as compared to known compounds.
[0016] It is another object of the present invention to provide compounds which are (1) absorbed less rapidly from mucosal surfaces, especially airway surfaces, as compared to known compounds and; (2) when absorbed from mucosal surfaces after administration to the mucosal surfaces, are converted in vivo into metabolic derivatives thereof which have reduced efficacy in blocking sodium channels and beta-adrenergic receptor agonist activity as compared to the administered parent compound.
[0017] It is another object of the present invention to provide compounds that are more potent and/or absorbed less rapidly and/or exhibit less reversibility, as compared to compounds such as amiloride, benzamil, and phenamil. Therefore, such compounds will give a prolonged pharmacodynamic half-life on mucosal surfaces as compared to previous compounds.
[0018] It is another object of the present invention to provide methods of treatment that take advantage of the pharmacological properties of the compounds described above.
[0019] In particular, it is an object of the present invention to provide methods of treatment which rely on rehydration of mucosal surfaces.
[0020] Any of the compounds described herein can be a pharmaceutically acceptable salt thereof, and wherein the above compounds are inclusive of all racemates, enantiomers, diastereomers, tautomers, polymorphs and pseudopolymorphs thereof. Polymorphs are different physical forms—different crystal forms that have differing melting ranges, show differing differential scanning calorimetry (DSC) tracings and exhibit different X-Ray powder diffraction (XRPD) spectra. Pseudopolymorphs are different solvated physical forms—different crystal forms that have differing melting ranges as solvates, show differing differential scanning calorimetry (DSC) tracings as solvates and exhibit different X-Ray powder diffraction (XRPD) spectra as solvates.
[0021] The present invention also provides pharmaceutical compositions which contain a compound described above.
[0022] The present invention also provides a method of promoting hydration of mucosal surfaces, comprising:
[0023] administering an effective amount of a compound represented by formula (I) to a mucosal surface of a subject.
[0024] The present invention also provides a method of restoring mucosal defense, comprising:
[0025] topically administering an effective amount of compound represented by formula (I) to a mucosal surface of a subject in need thereof.
[0026] The present invention also provides a method of blocking ENaC and exerting beta-adrenergic receptor agonism comprising:
[0027] contacting sodium channels and at the same time activating beta-adrenergic receptors (beta agonists) with an effective amount of a compound represented by formula (I).
[0028] The objects of the resent invention may be accomplished with a class of pyrazinoylguanidine compounds representing a compound represented by formula (I):
[0000]
[0000] wherein
[0029] X is hydrogen, halogen, trifluoromethyl, lower alkyl, unsubstituted or substituted phenyl, lower alkyl-thio, phenyl-lower alkyl-thio, lower alkyl-sulfonyl, or phenyl-lower alkyl-sulfonyl;
[0030] Y is hydrogen, hydroxyl, mercapto, lower alkoxy, lower alkyl-thio, halogen, lower alkyl, unsubstituted or substituted mononuclear aryl, or —N(R 2 ) 2 ;
[0031] R 1 is hydrogen or lower alkyl;
[0032] each R 2 is, independently, —R 7 , —(CH 2 ) m —OR 8 , —(CH 2 ) m —NR 7 R 10 , —(CH 2 ) n (CHOR 8 )(CHR 8 ) n —CH 2 OR 8 , —(CH 2 CH 2 O) m —R 8 , —(CH 2 CH 2 O) m —CH 2 CH 2 NR 7 R 10 , —(CH 2 ) n —C(═O)NR 7 R 10 , —(CH 2 ) n —Z g —R 7 , —(CH 2 ) m —NR 10 —CH 2 (CHOR 8 )(CHOR 8 ) n —CH 2 OR 8 , —(CH 2 ) n —CO 2 R 7 , or
[0000]
[0033] R 3 and R 4 are each, independently, hydrogen, a group represented by formula (A), lower alkyl, hydroxy lower alkyl, phenyl, phenyl-lower alkyl, (halophenyl)-lower alkyl, lower-(alkylphenylalkyl), lower (alkoxyphenyl)-lower alkyl, naphthyl-lower alkyl, or pyridyl-lower alkyl, with the proviso that at least one of R 3 and R 4 is a group represented by formula (A):
[0000] —(C(R L ) 2 ) O - x -(C(R L ) 2 ) P —CR 5 R 6 R 6 (A)
[0034] wherein each R L is, independently, —R 7 , —(CH 2 ) n —OR 8 , —O—(CH 2 ) m —OR 8 , —(CH 2 ) n —NR 7 R 10 , —O—(CH 2 ) m —NR 7 R 10 , —(CH 2 ) n (CHOR 8 )(CHOR 8 ) n —CH 2 OR 8 , —O—(CH 2 ) m (CHOR 8 )(CHOR 8 ) n —CH 2 OR 8 , —(CH 2 CH 2 O) m —R 8 , —O—(CH 2 CH 2 O) m —R 8 , —(CH 2 CH 2 O) m —CH 2 CH 2 NR 7 R 10 , —O—(CH 2 CH 2 O) m —CH 2 CH 2 NR 7 R 10 , —(CH 2 ) n —C(═O)NR 7 , R 10 , —O—(CH 2 ) m —C(═O)NR 7 R 10 , —(CH 2 ) n —(Z) g —R 7 , —O—(CH 2 ) m —(Z) g —R 7 , —(CH 2 ) n —NR 10 —CH 2 (CHOR 8 )(CHOR 8 ) n —CH 2 OR 8 , —O—(CH 2 ) m —NR 10 —CH 2 (CHOR 8 )(CHOR 8 ) n —CH 2 OR 8 , —(CH 2 ) n —CO 2 R 7 , —O—(CH 2 ) m —CO 2 R 7 , —OSO 3 H, —O-glucuronide, —O-glucose,
[0000]
[0035] each o is, independently, an integer from 0 to 10;
[0036] each p is an integer from 0 to 10;
[0037] with the proviso that the sum of o and p in each contiguous chain is from 1 to 10;
[0038] each x is, independently, O, NR 10 , C(═O), CHOH, C(═N—R 10 ), CHNR 7 , R 10 , or represents a single bond;
[0039] wherein each R 5 is, independently,
Link —(CH 2 ) n —CR 11 R 11 -CAP, Link —(CH 2 ) n (CHOR 8 )(CHOR 8 )—CR 11 R 11 -CAP, Link —(CH 2 CH 2 O) m —CH 2 —CR 11 R 11 -CAP, Link —(CH 2 CH 2 O) m —CH 2 CH 2 — CR 11 R 11 -CAP, Link —(CH 2 ) n —(Z) g —CR 11 R 11 -CAP, Link —(CH 2 ) n (Z) g —(CH 2 ) m —CR 11 R 11 -CAP, Link —(CH 2 ) n —NR 13 —CH 2 (CHOR 8 )(CHOR 8 ) n —CR 11 R 11 -CAP, Link —(CH 2 ) n —(CHOR 8 ) m —CH 2 —NR 13 —(Z) g —CR 11 R 11 -CAP, Link —(CH 2 ) n NR 13 —(CH 2 ) m (CHOR 8 ) n CH 2 NR 13 —(Z) g —CR 11 R 11 -CAP, Link —(CH 2 ) m —(Z) g —(CH 2 ) m —CR 11 R 11 -CAP, Link NH—C(═O)—NH—(CH 2 ) m —CR 11 R 11 -CAP, Link —(CH 2 ) m —C(═O)NR 13 —(CH 2 ) m —CR 11 R 11 -CAP, Link —(CH 2 ) n —(Z) g —(CH 2 ) m —(Z) g —CR 11 R 11 -CAP, Link —Z g —(CH 2 ) m -Het-(CH 2 ) m —CR 11 R 11 -CAP.
[0041] wherein Link is, independently,
—O—, (CH 2 ) n —, —O(CH 2 ) m —, —NR 13 —C(═O)—NR 13 , —NR 13 —C(═O)—(CH 2 ) m —, —C(═O)NR 13 —(CH 2 ) m , —(CH 2 ) n —Z g —(CH 2 ) n , —S—, —SO—, —SO 2 —, SO 2 NR 7 —, SO 2 NR 10 —, -Het-.
[0043] wherein each CAP is, independently,
[0000]
each R 6 is, independently, —R 7 , —OR 7 , —OR 11 , —N(R 7 ) 2 , —(CH 2 ) m —OR 8 , —O—(CH 2 ) m —OR 8 , —(CH 2 ) n —NR 7 , R 10 , —O—(CH 2 ) m —NR 7 R 10 , —(CH 2 ) n (CHOR 8 )(CHOR 8 ) n —CH 2 OR 8 , —O—(CH 2 ) m (CHOR 8 )(CHOR 8 ) n —CH 2 OR 8 , —(CH 2 CH 2 O) m —R 8 , —O—(CH 2 CH 2 O) m —R 8 , —(CH 2 CH 2 O) m —CH 2 CH 2 NR 7 R 10 , —O—(CH 2 CH 2 O) m —CH 2 CH 2 NR 7 R 10 , —(CH 2 ) n —C(═O)NR 7 R 10 , —O—(CH 2 ) m —C(═O)NR 7 R 10 , —(CH 2 ) n —(Z) g —R 7 , —O—(CH 2 ) m —(Z) g —R 7 , —(CH 2 ) n —NR 10 —CH 2 (CHOR 8 )(CHOR 8 ) n —CH 2 OR 8 , —O—(CH 2 ) m —NR 10 —CH 2 (CHOR 8 )(CHOR 8 ) n —CH 2 OR 8 , —(CH 2 ) n —CO 2 R 7 , —O—(CH 2 ) m —CO 2 R 7 , —OSO 3 H, —O-glucuronide, —O-glucose,
[0000]
[0045] where when two R 6 are —OR 11 and are located adjacent to each other on a phenyl ring, the alkyl moieties of the two R 6 may be bonded together to form a methylenedioxy group; with the proviso that when at least two —CH 2 OR 8 are located adjacent to each other, the R 8 groups may be joined to form a cyclic mono- or di-substituted 1,3-dioxane or 1,3-dioxolane,
[0046] each R 7 is, independently, hydrogen lower alkyl, phenyl, or substituted phenyl;
[0047] each R 8 is, independently, hydrogen, lower alkyl, —C(═O)—R 11 , glucuronide, 2-tetrahydropyranyl, or
[0000]
[0048] each R 9 is, independently, —CO 2 R 13 , —CON(R 13 ) 2 , —SO 2 CH 2 R 13 , or —C(═O)R 13 ;
[0049] each R 10 is, independently, —H, —SO 2 CH 3 , —CO 2 R 7 , —C(═O)NR 7 R 9 , —C(═O)R 7 , or —(CH 2 ) m —(CHOH) n —CH 2 OH;
[0050] each Z is, independently, CHOH, C(═O), —(CH 2 ) n —CHNR 13 R 13 , C═NR 13 , or NR 13 ;
[0051] each R 11 is, independently, hydrogen, lower alkyl, phenyl lower alkyl or substituted phenyl lower alkyl;
[0052] each R 12 is independently, —(CH 2 ) n —SO 2 CH 3 , —(CH 2 ) n —CO 2 R 13 , —(CH 2 ) n —C(═O)NR 13 R 13 , —(CH 2 ) n —C(═O)R 13 , —(CH 2 ) n —(CHOH) n —CH 2 OH, —NH—(CH 2 ) n —SO 2 CH 3 , NH—(CH 2 ) n —C(═O)R 11 , —NH—C(═O)—NH—C(═O)R 11 , —C(═O)NR 13 R 13 , —OR 11 , —NH—(CH 2 ) n —R 10 , —Br, —Cl, —F, —I, SO 2 NHR 11 , —NHR 13 , —NH—C(═O)—NR 13 R 13 , NH—(CH 2 )—SO 2 CH 3 , NH—(CH 2 ) n —C(═O)R 11 , —NH—C(═O)—NH—C(═O)R 11 , —C(═O)NR 13 R 13 , —OR 11 , —(CH 2 ) n —NHR 13 , —NH—C(═O)—NR 13 R 13 , or —NH—(CH 2 ) n —C(═O)—R 13 ;
[0053] each R 13 is, independently, hydrogen, lower alkyl, phenyl, substituted phenyl, —
[0000]
[0000] with the proviso that NR 13 R 13 can be joined on itself to form a group represented by one of the following:
[0000]
[0054] each Het is independently, —NR 13 , —S—, —SO—, —SO 2 —; —O—, —SO 2 NR 13 —, —NHSO 2 —, —NR 13 CO—, or —CONR 13 —;
[0055] each g is, independently, an integer from 1 to 6;
[0056] each m is, independently, an integer from 1 to 7;
[0057] each n is, independently, an integer from 0 to 7;
[0000]
[0000] with the proviso that when V is attached directly to a nitrogen atom, then V can also be, independently, R 7 , R 10 , or (R 11 ) 2 ;
wherein for any of the above compounds when two —CH 2 OR 8 groups are located 1,2- or 1,3- with respect to each other the R 8 groups may be joined to form a cyclic mono- or di-substituted 1,3-dioxane or 1,3-dioxolane; wherein any of the above compounds can be a pharmaceutically acceptable salt thereof, and wherein the above compounds are inclusive of all racemates, enantiomers, diastereomers, tautomers, polymorphs and pseudopolymorphs thereof.
[0060] The present invention also provides pharmaceutical compositions which contain a compound described above.
[0061] The present invention also provides a method of promoting hydration of mucosal surfaces, comprising:
[0062] administering an effective amount of a compound represented by formula (I) to a mucosal surface of a subject.
[0063] The present invention also provides a method of restoring mucosal defense, comprising:
[0064] topically administering an effective amount of compound represented by formula (I) to a mucosal surface of a subject in need thereof.
[0065] The present invention also provides a method of blocking ENaC, comprising:
[0066] contacting sodium channels with an effective amount of a compound represented by formula (I).
[0067] The present invention also provides a method of promoting mucus clearance in mucosal surfaces, comprising:
[0068] administering an effective amount of a compound represented by formula (I) to a mucosal surface of a subject.
[0069] The present invention also provides a method of treating chronic bronchitis, comprising:
[0070] administering an effective amount of a compound represented by formula (I) to a subject in need thereof.
[0071] The present invention also provides a method of treating cystic fibrosis, comprising:
[0072] administering an effective amount of compound represented by formula (I) to a subject in need thereof.
[0073] The present invention also provides a method of treating rhinosinusitis, comprising:
[0074] administering an effective amount of a compound represented by a formula (I) to a subject in need thereof.
[0075] The present invention also provides a method of treating nasal dehydration, comprising:
[0076] administering an effective amount of a compound represented by formula (I) to the nasal passages of a subject in need thereof.
[0077] In a specific embodiment, the nasal dehydration is brought on by administering dry oxygen to the subject.
[0078] The present invention also provides a method of treating sinusitis, comprising:
[0079] administering an effective amount of a compound represented by formula (I) to a subject in need thereof.
[0080] The present invention also provides a method of treating pneumonia, comprising:
[0081] administering an effective amount of a compound represented by formula (I) to a subject in need thereof.
[0082] The present invention also provides a method of preventing ventilator-induced pneumonia, comprising:
[0083] administering an effective compound represented by formula (I) to a subject by means of a ventilator.
[0084] The present invention also provides a method of treating asthma, comprising:
[0085] administering an effective amount of a compound represented by formula (I) to a subject in need thereof.
[0086] The present invention also provides a method of treating primary ciliary dyskinesia, comprising:
[0087] administering an effective amount of a compound represented by formula (I) to a subject in need thereof.
[0088] The present invention also provides a method of treating otitis media, comprising:
[0089] administering an effective amount of a compound represented by formula (I) to a subject in need thereof.
[0090] The present invention also provides a method of inducing sputum for diagnostic purposes, comprising:
[0091] administering an effective amount of compound represented by formula (I) to a subject in need thereof.
[0092] The present invention also provides a method of treating chronic obstructive pulmonary disease, comprising:
[0093] administering an effective amount of a compound represented by formula (I) to a subject in need thereof.
[0094] The present invention also provides a method of treating emphysema, comprising:
[0095] administering an effective amount of a compound represented by formula (I) to a subject in need thereof.
[0096] The present invention also provides a method of treating dry eye, comprising:
[0097] administering an effective amount of a compound represented by formula (I) to the eye of the subject in need thereof.
[0098] The present invention also provides a method of promoting ocular hydration, comprising:
[0099] administering an effective amount of a compound represented by formula (I) to the eye of the subject.
[0100] The present invention also provides a method of promoting corneal hydration, comprising:
[0101] administering an effective amount of a compound represented by formula (I) to the eye of the subject.
[0102] The present invention also provides a method of treating Sjögren's disease, comprising:
[0103] administering an effective amount of compound represented by formula (I) to a subject in need thereof.
[0104] The present invention also provides a method of treating vaginal dryness, comprising:
[0105] administering an effective amount of a compound represented by formula (I) to the vaginal tract of a subject in need thereof.
[0106] The present invention also provides a method of treating dry skin, comprising:
[0107] administering an effective amount of a compound represented by formula (I) to the skin of a subject in need thereof.
[0108] The present invention also provides a method of treating dry mouth (xerostomia), comprising:
[0109] administering an effective amount of compound represented by formula (I) to the mouth of the subject in need thereof.
[0110] The present invention also provides a method of treating distal intestinal obstruction syndrome, comprising:
[0111] administering an effective amount of compound represented by formula (I) to a subject in need thereof.
[0112] The present invention also provides a method of treating esophagitis, comprising:
[0113] administering an effective amount of a compound represented by formula (I) to a subject in need thereof.
[0114] The present invention also provides a method of treating constipation, comprising:
[0115] administering an effective amount of a compound represented by formula (I) to a subject in need thereof. In one embodiment of this method, the compound is administered either orally or via a suppository or enema.
[0116] The present invention also provides a method of treating chronic diverticulitis comprising:
[0117] administering an effective amount of a compound represented by formula (I) to a subject in need thereof.
BRIEF DESCRIPTION OF THE FIGURES
[0118] FIG. 1 shows the baseline activity of sodium channels before and after blockade with arniloride.
[0119] FIG. 2 shows the activity of sodium channels before and after the addition of a beta-agonist.
[0120] FIG. 3 shows the mechanism underlying the additivity of a Na channel blocker and a beta-agonist.
[0121] FIG. 4 shows the tautomers of the compounds of formula I.
DETAILED DESCRIPTION OF THE INVENTION
[0122] The present invention is based on the discovery that the compounds of formula (I) also possess both sodium channel blocking activity and beta agonist activity in the same molecule.
[0123] The present invention is also based on the discovery that the compounds of formula (I) are more potent and/or, absorbed less rapidly from mucosal surfaces, especially airway surfaces, and/or less reversible from interactions with ENaC as compared to compounds such as amiloride, benzamil, and phenamil. Therefore, the compounds of formula (I) have a longer half-life on mucosal surfaces as compared to these compounds.
[0124] The present invention is also based on the discovery that certain compounds embraced by formula (I) are converted in vivo into metabolic derivatives thereof that have reduced efficacy in blocking sodium channels and acting as beta-adrenergic receptor agonists as compared to the parent administered compound, after they are absorbed from mucosal surfaces after administration. This important property means that the compounds will have a lower tendency to cause undesired side-effects by blocking sodium channels and activating beta-receptors located at other untargeted locations in the body of the recipient, e.g., in the kidneys and heart. . . .
[0125] Mono drug therapy leaves most major diseases such as chronic bronchitis and cystic fibrosis inadequately treated. It is therefore often necessary to discover and develop novel drugs or combination of drugs which treat and modulate multiple targets simultaneously (polypharmacology) with the goal of enhancing efficacy or improving safety relative to single target drugs. There are three possible ways to achieve this. 1) Combining therapeutic “cocktails” of two or more individual drugs; the benefits of this approach are often lessened by poor patient compliance. 2). A multiple component drug (“fixed combination” or multiple component drug) that contains two or more agents in a single tablet, liquid formulation, inhaler or dry powder device. This can sometimes improve patient compliance versus multiple component drugs but adds the complexity of carefully dosing so as to minimize multiple metabolic pathways. 3). A single molecular entity which can simultaneously modulate multiple drug targets (designed multiple ligands). The advantage of a multiple ligand over the first two approaches is that it improves compliance, enhances efficacy, it targets a known set of deficiencies in multiple systems with a single new chemical entity, it often lacks the unpredictable differences in the pharmacokinetic and pharmacodynamic variability between patients, it is often easier to formulate and potentially lowers the risk of drug-drug interactions compared to drug cocktails and multiple component drugs. It was therefore our goal to discover multiple ligands that have both sodium channel blocking activity as well as beta agonist activity.
[0126] The addition of beta-adrenergic receptor agonist activity to a sodium channel blocker will significantly increase the capacity to hydrate airway surfaces in subjects in need of hydration for therapeutic purposes. The mechanism by which beta-agonist activity adds to the hydration capacity of Na channel blockers alone, or beta-agonists alone, is described in the following diagrams that describe the electrochemical gradients for ion flows and the net secretion that results from these forces in airway epithelia.
[0127] As shown in FIG. 1 , under baseline conditions human airway epithelia absorb NaCl and H 2 O. Active Na − absorption drives this process. Cl − is absorbed passively with Na + to preserve electroneutrality. As there is no net driving force for Cl − to move across the apical cell membrane, Cl − is absorbed paracellularly in response to the transepithelial electric potential. Water moves cellularly and paracellularly in response to the osmotic gradients generated by NaCl absorbtion.
[0128] Application of a Na + channel blocker (as an example amiloride is shown) inhibits the entry of Na + into the cell which: (1) abolishes Na + absorption and (2) hyperpolarizes the apical cell membrane (Va). The hyperpolarization of Va generates an electrochemical driving force favoring Cr secretion (Na + now follows in the secretory direction via the paracellularpath). The rate of Cl − secretion is proportional to the activity of the apicalmembrane Cl − channels which are typically 30-50% maximally active under basal conditions. In summary, application of a Na + channel blocker inhibits Na + absorption and triggers a modest amount of Cl − secretion. Note again that water will follow transcellularly in response to the secreted NaCl.
[0129] In contrast, as depicted in FIG. 2 , addition of a beta-agonist (as an example isoproterenol is shown) alone to human airway epithelia produces no changes in Na + absorption or Cl − secretion. The reason for this absence of effect is that there is no electrochemical driving force for Cl − to move across the cell (See the following references: Intracellular Cl− activity and cellular Cl− pathways in cultured human airway epithelium. Am J Physiol. 1989 May; 256(5 Pt 1):C1033-44. Willumsen N J, Davis C W, Boucher R C Cellular Cl− transport in cultured cystic fibrosis airway epithelium. Am J Physiol. 1989 May; 256(5 Pt 1):C1045-53. Willumsen N J, Davis C W, Boucher R C Activation of an apical Cl− conductance by Ca2+ ionophores in cystic fibrosis airway epithelia. Am J Physiol. 1989 February; 256(2 Pt 1):C226-33. Willumsen N J, Boucher R C). Thus, a beta-agonist mediated activation of an apical membrane Cl − channel, usually CFTR via changes in cAMP, produces no change in the rate of movement of Cl − across the barrier and, hence, no change in transepithelial sodium chloride or water secretion.
[0130] However, when a Na channel blocker is administered with a beta-agonist, additivity between these two classes of compounds is achieved with the result being accelerated Cl − (and Na + , H 2 O) secretion. The mechanism underlying the additivity is shown in FIG. 3 . In the presence of a Na channel blocker, an electrochemical gradient for Cl − secretion is generated (also see FIG. 1 ). Now when a beta-agonist is present, it converts the apical membrane CFTR from −30% basal activity to ˜100% activity via beta-agonist induced increase in cAMP that ultimately activates CFTR via PKA (protein kinase A). Because there is an electrochemical driving force favoring Cl − secretion as a result of ENaC blockade, the increase in Cl − channel activity translates into increasing Cl − (and Na + , H 2 O) secretion. Thus, the hydration capacity of the epithelia is greatly enhanced by the presence of both Na + channel blocker and beta-adrenergic receptor agonist activities in the environment bathing the human airway epithelia as compared to just Na + channel blocker or beta-adrenergic receptor agonist by themselves. A discovery of this invention is that administration of both activities contained within the same molecule to the epithelium is at least as effective as sequential administration of a Na channel blocker followed by a beta-agonist and therefore has the advantages cited earlier.
[0131] The compounds of formula I exist primarily as a combination of the three tautomers shown in FIG. 4 . The compounds of formula I exist primarily as a combination of the three tautomers shown in FIG. 4 . FIG. 4 shows the three tautomers represented in formula I that exist in solution. Previous studies (R L Smith et. Al. Journal of the American Chemical Society, 1979, 101, 191-201) have shown that the free base exists primarily as the acylimino tautomer, whereas the physiologically active species exists as the protonated form of the acylamino. These structural representations have been used to represent amiloride and its analogs in both the patent and scientific literature. We use both the acylamino and acylimino representations for convenience throughout this patent with the understanding that the structures are in reality a hybrid of the three forms with the actual amount of each dependent on the pH, the cite of action and the nature of the substituents.
[0132] In the compounds represented by formula (I), X may be hydrogen, halogen, trifluoromethyl, lower alkyl, lower cycloalkyl, unsubstituted or substituted phenyl, lower alkyl-thio, phenyl-lower alkyl-thio, lower alkyl-sulfonyl, or phenyl-lower alkyl-sulfonyl. Halogen is preferred.
[0133] Examples of halogen include fluorine, chlorine, bromine, and iodine. Chlorine and bromine are the preferred halogens. Chlorine is particularly preferred. This description is applicable to the term “halogen” as used throughout the present disclosure.
[0134] As used herein, the term “lower alkyl” means an alkyl group having less than 8 carbon atoms. This range includes all specific values of carbon atoms and subranges there between, such as 1,2, 3, 4, 5, 6, and 7 carbon atoms. The term “alkyl” embraces all types of such groups, e.g., linear, branched, and cyclic alkyl groups. This description is applicable to the term “lower alkyl” as used throughout the present disclosure. Examples of suitable lower alkyl groups include methyl, ethyl, propyl, cyclopropyl, butyl, isobutyl, etc.
[0135] Substituents for the phenyl group include halogens. Particularly preferred halogen substituents are chlorine and bromine.
[0136] Y may be hydrogen, hydroxyl, mercapto, lower alkoxy, lower alkyl-thio, halogen, lower alkyl, lower cycloalkyl, mononuclear aryl, or —N(R 2 ) 2 . The alkyl moiety of the lower alkoxy groups is the same as described above. Examples of mononuclear aryl include phenyl groups. The phenyl group may be unsubstituted or substituted as described above. The preferred identity of Y is —N(R 2 ) 2 . Particularly preferred are such compounds where each R 2 is hydrogen.
[0137] R 1 may be hydrogen or lower alkyl. Hydrogen is preferred for R 1 .
[0138] Each R 2 may be, independently, —R 7 , —(CH 2 ) m —OR 8 , —(CH 2 ) m —NR 7 R 10 , —(CH 2 ) n (CHOR 8 )(CHOR 8 ) n —CH 2 OR 8 , —(CH 2 CH 2 O) m —R 8 , —(CH 2 CH 2 O) m —CH 2 CH 2 NR 7 R 10 , —(CH 2 ) n —C(═O)NR 7 R 10 , —(CH 2 ) n —Z g —R 7 , —(CH 2 ) m —NR 10 —CH 2 (CHOR 8 )(CHOR 8 ) n —CH 2 OR 8 , —(CH 2 ) n —CO 2 R 7 , or
[0000]
[0139] Hydrogen and lower alkyl, particularly C 1 -C 3 alkyl are preferred for R 2 . Hydrogen is particularly preferred.
[0140] R 3 and R 4 may be, independently, hydrogen, a group represented by formula (A), lower alkyl, hydroxy lower alkyl, phenyl, phenyl-lower alkyl, (halophenyl)-lower alkyl, lower-(alkylphenylallyl), lower (alkoxyphenyl)-lower alkyl, naphthyl-lower alkyl, or pyridyl-lower alkyl, provided that at least one of R 3 and R 4 is a group represented by formula (A).
[0141] Preferred compounds are those where one of R 3 and R 4 is hydrogen and the other is represented by formula (A).
[0142] In formula (A), the moiety —(C(R L ) 2 ) o -x-(C(R L ) 2 ) p — defines an alkylene group. The variables o and p may each be an integer from 0 to 10, subject to the proviso that the sum of o and p in the chain is from 1 to 10. Thus, o and p may each be 0, 1, 2, 3, 4, 5, 6, 7 , 8, 9, or 10. Preferably, the sum of o and p is from 2 to 6. In a particularly preferred embodiment, the sum of o and p is 4.
[0143] The linking group in the alkylene chain, x, may be, independently, O, NR 10 , C(═O), CHOH, C(═N—R 10 ), CHNR 7 R 10 , or represents a single bond;
[0144] Therefore, when x represents a single bond, the alkylene chain bonded to the ring is represented by the formula —(C(R L ) 2 ) o+p —, in which the sum o+p is from 1 to 10.
[0145] Each R L may be, independently, —R 7 , —(CH 2 ) n —OR 8 , —O—(CH 2 ) m —OR 8 , —(CH 2 ) n —NR 7 , R 10 , —O—(CH 2 ) m —NR 7 R 10 , —(CH 2 ) n (CHOR 8 )(CHOR 8 ) n —CH 2 OR 8 , —O—(CH 2 ) m (CHOR 8 )(CHOR 8 ) n —CH 2 OR 8 , —(CH 2 CH 2 O) m —R 8 , —O—(CH 2 CH 2 O) m —R 8 , —(CH 2 CH 2 O) m —CH 2 CH 2 NR 7 R 10 , —O—(CH 2 CH 2 O) m —CH 2 CH 2 NR 7 R 10 , —(CH 2 ) n —C(═O)NR 7 R 10 , —O—(CH 2 ) m —C(═O)NR 7 R 10 , —(CH 2 ) n —(Z) g —R 7 , —O—(CH 2 ) m —(Z) g —R 7 , —(CH 2 ) n —NR 10 —CH 2 (CHOR 8 )(CHOR 8 ) n —CH 2 OR 8 , —O—(CH 2 ) m —NR 10 —CH 2 (CHOR 8 )(CHOR 8 ) n —CH 2 OR 8 , —(CH 2 ) n —CO 2 R 7 , —O—(CH 2 ) m —CO 2 R 7 , —OSO 3 H, —O-glucuronide, —O-glucose,
[0000]
[0146] The preferred R L groups include —H, —OH, —N(R 7 ) 2 , especially where each R 7 is hydrogen.
[0147] In the alkylene chain in formula (A), it is preferred that when one R L group bonded to a carbon atoms is other than hydrogen, then the other R L bonded to that carbon atom is hydrogen, i.e., the formula —CHR L —. It is also preferred that at most two R L groups in an alkylene chain are other than hydrogen, where in the other R L groups in the chain are hydrogens. Even more preferably, only one R L group in an alkylene chain is other than hydrogen, where in the other R L groups in the chain are hydrogens. In these embodiments, it is preferable that x represents a single bond.
[0148] In another particular embodiment of the invention, all of the R L groups in the alkylene chain are hydrogen. In these embodiments, the alkylene chain is represented by the formula —(CH 2 ) o -x-(CH 2 ) p —.
Each R 5 is, independently, Link —(CH 2 )—CR 11 R 11 -CAP, Link —(CH 2 ) n (CHOR 8 )(CHOR 8 ) n —CR 11 R 11 -CAP, Link —(CH 2 CH 2 O) m —CH 2 —CR 11 R 11 -CAP, Link —(CH 2 CH 2 O) m —CH 2 CH 2 —CR 11 R 11 -CAP, Link —(CH 2 ) n —(Z) g —CR 11 R 11 -CAP, Link —(CH 2 ) n (Z) g —(CH 2 ) m —CR 11 R 11 -CAP, Link —(CH 2 )—NR 13 —CH 2 (CHOR 8 )(CHOR 8 ) n —CR 11 R 11 -CAP, Link —(CH 2 ) n —(CHOR 8 ) m —CH 2 —NR 13 —(Z) g —CR 11 R 11 -CAP, Link —(CH 2 ) n NR 13 —(CH 2 ) m (CHOR 8 ) n CH 2 NR 13 —(Z) g —CR 11 R 11 -CAP, Link —(CH 2 ) m —(Z) g —(CH 2 ) m —CR 11 R 11 -CAP, Link NH—C(═O)—NH—(CH 2 ) m —CR 11 R 11 -CAP, Link —(CH 2 ) m —C(═O)NR 13 —(CH 2 ) m —CR 11 R 11 -CAP, Link —(CH 2 ) n —(Z) g —(CH 2 ) m —(Z) g —CR 11 R 11 -CAP, or Link —Z g —(CH 2 ) m -Het-(CH 2 ) m —CR 11 R 11 -CAP. Each Link is, independently, —O—, (CH 2 ) n —, —O(CH 2 ) m , —NR 13 —C(═O)—NR 13 , —NR 13 —C(═O)—(CH 2 ) m —, —C(═O)NR 13 —(CH 2 ) m , —(CH 2 ) n —Z g —(CH 2 ) n , —S—, —SO—, —SO 2 —, SO 2 NR 7 —, SO 2 NR 10 —, -Het-. Each CAP is, independently,
[0000]
Each R 6 is, independently, —R 7 , —OR 7 , —OR 11 , —N(R 7 ) 2 , —(CH 2 ) m —OR 8 , —O—(CH 2 ) m —OR 8 , —(CH 2 ) n —NR 7 , R 10 , —O—CH 2 ) m —NR 11 R 10 , —(CH 2 ) n (CHOR 8 )(CHOR 8 ) n —CH 2 OR 8 , —O—(CH 2 ) m (CHOR 8 )(CHOR 8 ) n —CH 2 OR 8 , —(CH 2 CH 2 O) m —R 8 , —O—CH 2 CH 2 O) m —R 8 , —(CH 2 CH 2 O) m —CH 2 CH 2 NR 7 R 10 , —O—(CH 2 CH 2 O) m —CH 2 CH 2 NR 7 R 10 , —(CH 2 CH 2 O) m —R 8 , —(CH 2 CH 2 O) m —CH 2 CH 2 NR 7 R 10 , —O—(CH 2 ) m —C(═O)NR 7 R 10 , —(CH 2 ) n —C(═O)NR 7 R 10 , —(CH 2 ) n —NR 10 —CH 2 (CHOR 8 )(CHOR 8 ) n —CH 2 OR 8 , —O—(CH 2 ) m —NR 10 —CH 2 (CHOR 8 )(CHOR 8 ) n —CH 2 OR 8 , —(CH 2 ) n —CO 2 R 7 , —O—(CH 2 ) m —CO 2 R 7 , —OSO 3 H, —O-glucuronide, —O-glucose,
[0000]
[0155] Each R 7 is, independently, hydrogen lower alkyl, phenyl, or substituted phenyl.
[0156] Each R 8 is, independently, hydrogen, lower alkyl, —C(═O)—R 11 , glucuronide, 2-tetrahydropyranyl, or
[0000]
[0157] Each R 9 is, independently, —CO 2 R 13 , —CON(R 13 ) 2 , —SO 2 CH 2 R 13 , or —C(═O)R 13 .
[0158] Each R 10 is, independently, —H, —SO 2 CH 3 , —CO 2 R 7 , —C(═O)NR 7 R 9 , —C(═O)R 7 , or —(CH 2 ) m —(CHOH) n —CH 2 OH.
[0159] Each Z is, independently, CHOH, C(═O), —(CH 2 )—, CHNR 13 R 13 , C═NR 13 , or NR 13 .
[0160] Each R 11 is, independently, hydrogen, lower alkyl, phenyl lower alkyl or substituted phenyl lower alkyl.
[0161] Each R 12 is independently, —(CH 2 ), —SO 2 CH 3 , —(CH 2 ), —CO 2 R 13 , —(CH 2 ) n —C(═O)NR 13 R 13 , —(CH 2 ), —C(═O)R 13 , —(CH 2 ) n —(CHOH) n —CH 2 OH, —NH—(CH 2 ) n —SO 2 CH 3 , NH—(CH 2 ) n —C(═O)R 11 , NH—C(═O)—NH—C(═O)R 11 , —C(═O)NR 13 R 13 , —OR 11 , —NH—(CH 2 ) n —R 10 , —Br, —Cl, —F, —I, SO 2 NHR 11 , —NHR 13 , —NH—C(═O)—NR 13 R 13 , NH—(CH 2 ), —SO 2 CH 3 , NH—(CH 2 ) n —C(═O)R 11 , —NH—C(═O)—NH—C(═O)R 11 , —C(═O)NR 13 R 13 , —OR 11 , —(CH 2 ) n —NHR 13 , —NH—C(═O)—NR 13 R 13 , or —NH—(CH 2 ) n —C(═O)—R 13 ;
[0162] Each R 13 is, independently, hydrogen, lower alkyl, phenyl, substituted phenyl, —
[0000]
[0000] with the proviso that NR 13 R 13 can be joined on itself to form a group represented by one of the following:
[0000]
[0163] Each Het is independently, —NR 13 , —S—, —SO—, —SO 2 —; —O—, —SO 2 NR 13 —, —NHSO 2 —, —NR 13 CO—, —CONR 13 —.
[0164] Each g is, independently, an integer from 1 to 6.
[0165] Each m is, independently, an integer from 1 to 7.
[0166] Each n is, independently, an integer from 0 to 7.
[0000]
with the proviso that when V is attached directly to a nitrogen atom, then V can also be, independently, R 7 , R 10 , or (R 11 ) 2 .
[0168] In any of the compounds of the present invention, when two —CH 2 OR 8 groups are located 1,2- or 1,3- with respect to each other the R 8 groups may be joined to form a cyclic mono- or di-substituted 1,3-dioxane or 1,3-dioxolane.
[0000]
[0169] In another embodiment, when two R 6 are —OR 11 and are located adjacent to each other on a phenyl ring, the alkyl moieties of the two R 6 may be bonded together to form a methylenedioxy group.
[0170] In still another embodiment of the invention, when at least two —CH 2 OR 8 are located adjacent to each other, the R 8 groups may be joined to form a cyclic mono- or di-substituted 1,3-dioxane or 1,3-dioxolane.
[0171] In addition, one of more of the R 6 groups can be one of the R 5 groups which fall within the broad definition of R 6 set forth above.
[0172] As discussed above, R 6 may be hydrogen. Therefore, 1, 2, 3, or 4 R 6 groups may be other than hydrogen. Preferably at most 3 of the R 6 groups are other than hydrogen.
[0173] Each g is, independently, an integer from 1 to 6. Therefore, each g may be 1, 2, 3, 4, 5, or 6.
[0174] Each m is an integer from 1 to 7. Therefore, each m may be 1, 2, 3, 4, 5, 6, or 7.
[0175] Each n is an integer from 0 to 7. Therefore, each n may be 0, 1, 2, 3, 4, 5, 6, or 7.
[0176] More specific examples of suitable groups represented by formula (A) are shown in formula below:
[0000] —(C(R L ) 2 ) O - x -(C(R L ) 2 ) P —CR 5 R 6 R 6 (A)
[0177] in which each RL is hydrogen and where o, x, p, R 5 , and R 6 , are as defined above.
[0178] In a preferred embodiment of the invention, Y is —NH 2 .
[0179] In another preferred embodiment, R 2 is hydrogen.
[0180] In another preferred embodiment, R 1 is hydrogen.
[0181] In another preferred embodiment, X is chlorine.
[0182] In another preferred embodiment, R 3 is hydrogen.
[0183] In another preferred embodiment, R L is hydrogen.
[0184] In another preferred embodiment, o is 4.
[0185] In another preferred embodiment, p is 0.
[0186] In another preferred embodiment, the sum of o and p is 4.
[0187] In another preferred embodiment, x represents a single bond.
[0188] In another preferred embodiment, R 6 is hydrogen.
[0189] In another preferred embodiment, at most one Q is a nitrogen atom.
[0190] In another preferred embodiment, no Q is a nitrogen atom.
[0191] In a preferred embodiment of the present invention:
[0192] X is halogen;
[0193] Y is —N(R 7 ) 2 ;
[0194] R 1 is hydrogen or C 1 -C 3 alkyl;
[0195] R 2 is —R 7 , —OR 7 , CH 2 OR 7 , or —CO 2 R 7 ;
[0196] R 3 is a group represented by formula (A); and
[0197] R 4 is hydrogen, a group represented by formula (A), or lower alkyl;
[0198] In another preferred embodiment of the present invention:
[0199] X is chloro or bromo;
[0200] Y is —N(R 7 ) 2 ;
[0201] R 2 is hydrogen or C 1 -C 3 alkyl;
[0202] at most three R 6 are other than hydrogen as described above;
[0203] at most three R L are other than hydrogen as described above
[0204] In another preferred embodiment of the present invention:
[0205] Y is —NH 2 ;
[0206] In another preferred embodiment of the present invention:
[0207] R 4 is hydrogen;
[0208] at most one R L is other than hydrogen as described above; and
[0209] at most two R 6 are other than hydrogen as described above.
[0210] In addition, one of more of the R 6 groups can be one of the R 5 groups which fall within the broad definition of R 6 set forth above.
[0211] As discussed above, R 6 may be hydrogen. Therefore, 1 or 2 R 6 groups may be other than hydrogen. Preferably at most 3 of the R 6 groups are other than hydrogen.
[0212] Each g is, independently, an integer from 1 to 6. Therefore, each g maybe 1, 2, 3, 4, 5, or 6.
[0213] Each m is an integer from 1 to 7. Therefore, each m may be 1, 2, 3, 4, 5, 6, or 7.
[0214] Each n is an integer from 0 to 7. Therefore, each n maybe 0, 1, 2, 3, 4, 5, 6, or 7.
[0215] In a preferred embodiment of the invention, Y is —NH 2 .
[0216] In another preferred embodiment, R 2 is hydrogen.
[0217] In another preferred embodiment, R 1 is hydrogen.
[0218] In another preferred embodiment, X is chlorine.
[0219] In another preferred embodiment, R 3 is hydrogen.
[0220] In another preferred embodiment, R L is hydrogen.
[0221] In another preferred embodiment, o is 4.
[0222] In another preferred embodiment, p is 2.
[0223] In another preferred embodiment, the sum of o and p is 6.
[0224] In another preferred embodiment, x represents a single bond.
[0225] In another preferred embodiment, R 6 is hydrogen.
[0226] In a preferred embodiment of the present invention:
[0227] X is halogen;
[0228] Y is —N(R 7 ) 2 ;
[0229] R 1 is hydrogen or C 1 -C 3 alkyl;
[0230] R 2 is —R 7 , —OR 7 , CH 2 O 7 , or —CO 2 R 7 ;
[0231] R 3 is a group represented by formula (A); and
[0232] R 4 is hydrogen, a group represented by formula (A), or lower alkyl;
[0233] In another preferred embodiment of the present invention:
[0234] X is chloro or bromo;
[0235] Y is —N(R 7 ) 2 ;
[0236] R 2 is hydrogen or C 1 -C 3 alkyl;
[0237] at most three R 6 are other than hydrogen as described above; and
[0238] at most three R L are other than hydrogen as described above;
[0239] In another preferred embodiment of the present invention:
[0240] Y is —NH 2 ;
[0241] In another preferred embodiment of the present invention:
[0242] R 4 is hydrogen;
[0243] at most one R L is other than hydrogen as described above; and
[0244] at most two R 6 are other than hydrogen as described above;
[0245] In another preferred embodiment of the present invention the compound of formula (1) is represented by the formula:
[0000]
[0246] In another preferred embodiment of the present invention the compound of formula (1) is represented by the formula:
[0000]
[0247] In another preferred embodiment of the present invention the compound of formula (1) is represented by the formula:
[0000]
[0248] In another preferred embodiment of the present invention the compound of formula (1) is represented by the formula:
[0000]
[0249] In another preferred embodiment of the present invention the compound of formula (1) is represented by the formula:
[0000]
[0250] In another preferred embodiment of the present invention the compound of formula (1) is represented by the formula:
[0000]
[0251] In another preferred embodiment of the present invention the compound of formula (1) is represented by the formula:
[0000]
[0252] In another preferred embodiment of the present invention the compound of formula (1) is represented by the formula:
[0000]
[0253] In another preferred embodiment of the present invention the compound of formula (1) is represented by the formula:
[0000]
[0254] In another preferred embodiment of the present invention the compound of formula (1) is represented by the formula:
[0000]
[0255] In another preferred embodiment of the present invention the compound of formula (1) is represented by the formula:
[0000]
[0256] In another preferred embodiment of the present invention the compound of formula (1) is represented by the formula:
[0000]
[0257] In another preferred embodiment of the present invention the compound of formula (1) is represented by the formula:
[0000]
[0258] In another preferred embodiment of the present invention the compound of formula (1) is represented by the formula:
[0000]
[0259] In another preferred embodiment of the present invention the compound of formula (1) is represented by the formula:
[0000]
[0260] In another preferred embodiment of the present invention the compound of formula (1) is represented by the formula:
[0000]
[0261] In another preferred embodiment of the present invention the compound of formula (1) is represented by the formula:
[0000]
[0262] In another preferred embodiment of the present invention the compound of formula (1) is represented by the formula:
[0000]
[0263] In another preferred embodiment of the present invention the compound of formula (1) is represented by the formula:
[0000]
[0264] In another preferred embodiment of the present invention the compound of formula (1) is represented by the formula:
[0000]
[0265] The compounds of formula (I) may be prepared and used as the free base. Alternatively, the compounds may be prepared and used as a pharmaceutically acceptable salt. Pharmaceutically acceptable salts are salts that retain or enhance the desired biological activity of the parent compound and do not impart undesired toxicological effects. Examples of such salts are (a) acid addition salts formed with inorganic acids, for example, hydrochloric acid, hydrobromic acid, sulfuric acid, phosphoric acid, nitric acid and the like; (b) salts formed with organic acids such as, for example, acetic acid, oxalic acid, tartaric acid, succinic acid, maleic acid, fumaric acid, gluconic acid, citric acid, malic acid, ascorbic acid, benzoic acid, tannic acid, palmitic acid, alginic acid, polyglutamic acid, naphthalenesulfonic acid, methanesulfonic acid, p-toluenesulfonic acid, naphthalenedisulfonic acid, polygalacturonic acid, malonic acid, sulfosalicylic acid, glycolic acid, 2-hydroxy-3-naphthoate, pamoate, salicylic acid, stearic acid, phthalic acid, mandelic acid, lactic acid and the like; and (c) salts formed from elemental anions for example, chlorine, bromine, and iodine.
[0266] It is to be noted that any of the above compounds can be a pharmaceutically acceptable salt thereof, and wherein the above compounds are inclusive of all racemates, enantiomers, diastereomers, tautomers, polymorphs and pseudopolymorphs thereof. Polymorphs are different physical forms—different crystal forms that have differing melting ranges, show differing differential scanning calorimetry (DSC) tracings and exhibit different X-Ray powder diffraction (XRPD) spectra. Pseudopolymorphs are different solvated physical forms—different crystal forms that have differing melting ranges as solvates, show differing differential scanning calorimetry (DSC) tracings as solvates and exhibit different X-Ray powder diffraction (XRPD) spectra as solvates.
[0267] Without being limited to any particular theory, it is believed that the compounds of formula (I) function in vivo as sodium channel blockers and beta receptor agonists. By blocking epithelial sodium channels by activating beta adrenergic receptors present in mucosal surfaces, the compounds of formula (I) reduce the absorption of water by the mucosal surfaces. This effect increases the volume of protective liquids on mucosal surfaces, rebalances the system, and thus treats disease.
[0268] The present invention also provides methods of treatment that take advantage of the properties of the compounds of formula (I) discussed above. Thus, subjects that may be treated by the methods of the present invention include, but are not limited to, patients afflicted with cystic fibrosis, primary ciliary dyskinesia, chronic bronchitis, chronic obstructive airway disease, artificially ventilated patients, patients with acute pneumonia, etc. The present invention may be used to obtain a sputum sample from a patient by administering the active compounds to at least one lung of a patient, and then inducing or collecting a sputum sample from that patient. Typically, the invention will be administered to respiratory mucosal surfaces via aerosol (liquid or dry powders) or lavage.
[0269] Subjects that may be treated by the method of the present invention also include patients being administered supplemental oxygen nasally (a regimen that tends to dry the airway surfaces); patients afflicted with an allergic disease or response (e.g., an allergic response to pollen, dust, animal hair or particles, insects or insect particles, etc.) that affects nasal airway surfaces; patients afflicted with a bacterial infection e.g., staphylococcus infections such as Staphylococcus aureus infections, Hemophilus influenza infections, Streptococcus pneumoniae infections, Pseudomonas aeuriginosa infections, etc.) of the nasal airway surfaces; patients afflicted with an inflammatory disease that affects nasal airway surfaces; or patients afflicted with sinusitis (wherein the active agent or agents are administered to promote drainage of congested mucous secretions in the sinuses by administering an amount effective to promote drainage of congested fluid in the sinuses), or combined, Rhinosinusitis. The invention may be administered to rhino-sinal surfaces by topical delivery, including aerosols and drops.
[0270] The present invention may be used to hydrate mucosal surfaces other than airway surfaces. Such other mucosal surfaces include gastrointestinal surfaces, oral surfaces, genito-urethral surfaces, ocular surfaces or surfaces of the eye, the inner ear and the middle ear. For example, the active compounds of the present invention may be administered by any suitable means, including locally/topically, orally, or rectally, in an effective amount.
[0271] The compounds of the present invention are also useful for treating a variety of functions relating to the cardiovascular system. Thus, the compounds of the present invention are useful for use as antihypertensive agents. The compounds may also be used to reduce blood pressure and to treat edema. In addition, the compounds of the present invention are also useful for promoting diuresis, natriuresis, and saluresis. The compounds may be used alone or in combination with beta blockers, ACE inhibitors, HMGCoA, reductase inhibitors, calcium channel blockers and other cardiovascular agents to treat hypertension, congestive heart failure and reduce cardiovascular mortality.
[0272] The compounds of the present invention are also useful for treating airborne infections. Examples of airborne infections include, for example, RSV. The compounds of the present invention are also useful for treating an anthrax infection.
[0273] The present invention is concerned primarily with the treatment of human subjects, but may also be employed for the treatment of other mammalian subjects, such as dogs and cats, for veterinary purposes.
[0274] As discussed above, the compounds used to prepare the compositions of the present invention may be in the form of a pharmaceutically acceptable free base. Because the free base of the compound is generally less soluble in aqueous solutions than the salt, free base compositions are employed to provide more sustained release of active agent to the lungs. An active agent present in the lungs in particulate form which has not dissolved into solution is not available to induce a physiological response, but serves as a depot of bioavailable drug which gradually dissolves into solution.
[0275] Another aspect of the present invention is a pharmaceutical composition, comprising a compound of formula (I) in a pharmaceutically acceptable carrier (e.g., an aqueous carrier solution). In general, the compound of formula (I) is included in the composition in an amount effective to inhibit the reabsorption of water by mucosal surfaces.
[0276] The compounds of the present invention may also be used in conjunction with a P2Y2 receptor agonist or a pharmaceutically acceptable salt thereof (also sometimes referred to as an “active agent” herein). The composition may further comprise a P2Y2 receptor agonist or a pharmaceutically acceptable salt thereof (also sometimes referred to as an “active agent” herein). The P2Y2 receptor agonist is typically included in an amount effective to stimulate chloride and water secretion by airway surfaces, particularly nasal airway surfaces. Suitable P2Y2 receptor agonists are described in columns 9-10 of U.S. Pat. No. 6,264,975, U.S. Pat. No. 5,656,256, and U.S. Pat. No. 5,292,498, each of which is incorporated herein by reference.
[0277] Bronchodiloators can also be used in combination with compounds of the present invention. These bronchodilators include, but are not limited to, anticholinergic agents including but not limited to ipratropium bromide, as well as compounds such as theophylline and aminophylline. These compounds may be administered in accordance with known techniques, either prior to or concurrently with the active compounds described herein.
[0278] Another aspect of the present invention is a pharmaceutical formulation, comprising an active compound as described above in a pharmaceutically acceptable carrier (e.g., an aqueous carrier solution). In general, the active compound is included in the composition in an amount effective to treat mucosal surfaces, such as inhibiting the reabsorption of water by mucosal surfaces, including airway and other surfaces.
[0279] Ionic and organic osmolytes can also be used in combination with compounds of the present invention. Ionic osmolytes useful include any salt consisting of a pharmaceutically acceptable anion and a pharmaceutical cation. Organic osmolytes include, but are not limited to, sugars, sugar alcohols and organic osmolytes. Detailed examples of ionic and non-ionic osmolytes are given in U.S. Pat. No. 6,926,911 incorporated herein by reference. A particularly useful ionic osmolyte is hypertonic sodium chloride or sodium nitrite. A particularly useful organic osmolyte is the reduced sugar mannitol.
[0280] The active compounds disclosed herein may be administered to mucosal surfaces by any suitable means, including topically, orally, rectally, vaginally, ocularly and dermally, etc. For example, for the treatment of constipation, the active compounds may be administered orally or rectally to the gastrointestinal mucosal surface. The active compound may be combined with a pharmaceutically acceptable carrier in any suitable form, such as sterile physiological or dilute saline or topical solution, as a droplet, tablet or the like for oral administration, as a suppository for rectal or genito-urethral administration, etc. Excipients may be included in the formulation to enhance the solubility of the active compounds, as desired.
[0281] The active compounds disclosed herein may be administered to the airway surfaces of a patient by any suitable means, including as a spray, mist, or droplets of the active compounds in a pharmaceutically acceptable carrier such as physiological or dilute saline solutions or distilled water. For example, the active compounds may be prepared as formulations and administered as described in U.S. Pat. No. 5,789,391 to Jacobus, the disclosure of which is incorporated by reference herein in its entirety.
[0282] Solid or liquid particulate active agents prepared for practicing the present invention could, as noted above, include particles of respirable or non-respirable size; that is, for respirable particles, particles of a size sufficiently small to pass through the mouth and larynx upon inhalation and into the bronchi and alveoli of the lungs, and for non-respirable particles, particles sufficiently large to be retained in the nasal airway passages rather than pass through the larynx and into the bronchi and alveoli of the lungs. In general, particles ranging from about 1 to 5 microns in size (more particularly, less than about 4.7 microns in size) are respirable. Particles of non-respirable size are greater than about 5 microns in size, up to the size of visible droplets. Thus, for nasal administration, a particle size in the range of 10-500 μm may be used to ensure retention in the nasal cavity.
[0283] In the manufacture of a formulation according to the invention, active agents or the physiologically acceptable salts or free bases thereof are typically admixed with, inter alia, an acceptable carrier. Of course, the carrier must be compatible with any other ingredients in the formulation and must not be deleterious to the patient. The carrier must be solid or liquid, or both, and is preferably formulated with the compound as a unit-dose formulation, for example, a capsule, that may contain 0.5% to 99% by weight of the active compound. One or more active compounds may be incorporated in the formulations of the invention, which formulations may be prepared by any of the well-known techniques of pharmacy consisting essentially of admixing the components.
[0284] Compositions containing respirable or non-respirable dry particles of micronized active agent may be prepared by grinding the dry active agent with a mortar and pestle, and then passing the micronized composition through a 400 mesh screen to break up or separate out large agglomerates.
[0285] The particulate active agent composition may optionally contain a dispersant which serves to facilitate the formulation of an aerosol. A suitable dispersant is lactose, which may be blended with the active agent in any suitable ratio (e.g., a 1 to 1 ratio by weight).
[0286] Active compounds disclosed herein may be administered to airway surfaces including the nasal passages, sinuses and lungs of a subject by an suitable means know in the art, such as by nose drops, mists, etc. In one embodiment of the invention, the active compounds of the present invention and administered by transbronchoscopic lavage. In a preferred embodiment of the invention, the active compounds of the present invention are deposited on lung airway surfaces by administering an aerosol suspension of respirable particles comprised of the active compound, which the subject inhales. The respirable particles may be liquid or solid. Numerous inhalers for administering aerosol particles to the lungs of a subject are known.
[0287] Inhalers such as those developed by Inhale Therapeutic Systems, Palo Alto, Calif., USA, may be employed, including but not limited to those disclosed in U.S. Pat. Nos. 5,740,794; 5,654,007; 5,458,135; 5,775,320; and 5,785,049, each of which is incorporated herein by reference. The Applicant specifically intends that the disclosures of all patent references cited herein be incorporated by reference herein in their entirety. Inhalers such as those developed by Dura Pharmaceuticals, Inc., San Diego, Calif., USA, may also be employed, including but not limited to those disclosed in U.S. Pat. Nos. 5,622,166; 5,577,497; 5,645,051; and 5,492,112, each of which is incorporated herein by reference. Additionally, inhalers such as those developed by Aradigm Corp., Hayward, Calif., USA, may be employed, including but not limited to those disclosed in U.S. Pat. Nos. 5,826,570; 5,813,397; 5,819,726; and 5,655,516, each of which is incorporated herein by reference. These apparatuses are particularly suitable as dry particle inhalers.
[0288] Aerosols of liquid particles comprising the active compound may be produced by any suitable means, such as with a pressure-driven aerosol nebulizer or an ultrasonic nebulizer. See, e.g., U.S. Pat. No. 4,501,729, which is incorporated herein by reference. Nebulizers are commercially available devices which transform solutions or suspensions of the active ingredient into a therapeutic aerosol mist either by means of acceleration of compressed gas, typically air or oxygen, through a narrow venturi orifice or by means of ultrasonic agitation. Suitable formulations for use in nebulizers consist of the active ingredient in a liquid carrier, the active ingredient comprising up to 40% w/w of the formulation, but preferably less than 20% w/w. The carrier is typically water (and most preferably sterile, pyrogen-free water) or dilute aqueous alcoholic solution. Perfluorocarbon carriers may also be used. Optional additives include preservatives if the formulation is not made sterile, for example, methyl hydroxybenzoate, antioxidants, flavoring agents, volatile oils, buffering agents and surfactants.
[0289] Aerosols of solid particles comprising the active compound may likewise be produced with any solid particulate medicament aerosol generator. Aerosol generators for administering solid particulate medicaments to a subject produce particles which are respirable, as explained above, and generate a volume of aerosol containing predetermined metered dose of medicament at a rate suitable for human administration. One illustrative type of solid particulate aerosol generator is an insufflator. Suitable formulations for administration by insufflation include finely comminuted powders which may be delivered by means of an insufflator or taken into the nasal cavity in the manner of a snuff. In the insufflator, the powder (e.g., a metered dose thereof effective to carry out the treatments described herein) is contained in capsules or cartridges, typically made of gelatin or plastic, which are either pierced or opened in situ and the powder delivered by air drawn through the device upon inhalation or by means of a manually-operated pump. The powder employed in the insufflator consists either solely of the active ingredient or of powder blend comprising the active ingredient, a suitable powder diluent, such as lactose, and an optional surfactant. The active ingredient typically comprises of 0.1 to 100% w/w of the formulation. A second type of illustrative aerosol generator comprises a metered dose inhaler. Metered dose inhalers are pressurized aerosol dispensers, typically containing a suspension or solution formulation of active ingredient in a liquified propellant. During use, these devices discharge the formulation through a valve adapted to deliver a metered volume, typically from 10 to 150 μl, to produce a fine particle spray containing the active ingredient. Suitable propellants include certain chlorofluorocarbon compounds, for example, dichlorodifluoromethane, trichlorofluoromethane, dichlorotetrafluoroethane and mixtures thereof. The formulation may additionally contain one of more co-solvents, for example, ethanol, surfactants, such as oleic acid or sorbitan trioleate, antioxidants and suitable flavoring agents.
[0290] The aerosol, whether formed from solid or liquid particles, may be produced by the aerosol generator at a rate of from about 10 to 150 liters per minute, more preferable from 30 to 150 liters per minute, and most preferably about 60 liters per minute. Aerosols containing greater amounts of medicament may be administered more rapidly.
[0291] The dosage of the active compounds disclosed herein will vary depending on the condition being treated and the state of the subject, but generally may be from about 0.01, 0.03, 0.05, 0.1 to 1, 5, 10 or 20 mg of the pharmaceutic agent, deposited on the airway surfaces. The daily dose may be divided among one or multiple unit dose administrations. The goal is to achieve a concentration of the pharmaceutic agents on lung airway surfaces of between 10 −9 -10 4 M.
[0292] In another embodiment, they are administered by administering an aerosol suspension of respirable or non-respirable particles (preferably non-respirable particles) comprised of active compound, which the subject inhales through the nose. The respirable or non-respirable particles may be liquid or solid. The quantity of active agent included may be an amount of sufficient to achieve dissolved concentrations of active agent on the airway surfaces of the subject of from about 10 −9 , 10 −8 , or 10 −7 to about 10 −3 , 10 −2 , 10 −1 moles/liter, and more preferably from about 10 −9 to about 10 4 moles/liter.
[0293] The dosage of active compound will vary depending on the condition being treated and the state of the subject, but generally may be an amount sufficient to achieve dissolved concentrations of active compound on the nasal airway surfaces of the subject from about 10 −9 , 10 −8 , 10 −7 to about 10 −3 , 10 −2 , or 10 −1 moles/liter, and more preferably from about 10 −7 to about 10 −4 moles/liter. Depending upon the solubility of the particular formulation of active compound administered, the daily dose may be divided among one or several unit dose administrations. The daily dose by weight may range from about 0.01, 0.03, 0.1, 0.5 or 1.0 to or 20 milligrams of active agent particles for a human subject, depending upon the age and condition of the subject. A currently preferred unit dose is about 0.5 milligrams of active agent given at a regimen of 2-10 administrations per day. The dosage may be provided as a prepackaged unit by any suitable means (e.g., encapsulating a gelatin capsule).
[0294] In one embodiment of the invention, the particulate active agent composition may contain both a free base of active agent and a pharmaceutically acceptable salt to provide both early release and sustained release of active agent for dissolution into the mucus secretions of the nose. Such a composition serves to provide both early relief to the patient, and sustained relief over time. Sustained relief, by decreasing the number of daily administrations required, is expected to increase patient compliance with the course of active agent treatments.
[0295] Pharmaceutical formulations suitable for airway administration include formulations of solutions, emulsions, suspensions and extracts. See generally, J. Nairn, Solutions, Emulsions, Suspensions and Extracts, in Remington: The Science and Practice of Pharmacy, chap. 86 (19 th ed. 1995), incorporated herein by reference. Pharmaceutical formulations suitable for nasal administration may be prepared as described in U.S. Pat. Nos. 4,389,393 to Schor; 5,707,644 to Illum; 4,294,829 to Suzuki; and 4,835,142 to Suzuki, the disclosures of which are incorporated by reference herein in their entirety.
[0296] Mists or aerosols of liquid particles comprising the active compound may be produced by any suitable means, such as by a simple nasal spray with the active agent in an aqueous pharmaceutically acceptable carrier, such as a sterile saline solution or sterile water. Administration may be with a pressure-driven aerosol nebulizer or an ultrasonic nebulizer. See e.g. U.S. Pat. Nos. 4,501,729 and 5,656,256, both of which are incorporated herein by reference. Suitable formulations for use in a nasal droplet or spray bottle or in nebulizers consist of the active ingredient in a liquid carrier, the active ingredient comprising up to 40% w/w of the formulation, but preferably less than 20% w/w. Typically the carrier is water (and most preferably sterile, pyrogen-free water) or dilute aqueous alcoholic solution, preferably made in a 0.12% to 0.8% solution of sodium chloride. Optional additives include preservatives if the formulation is not made sterile, for example, methyl hydroxybenzoate, antioxidants, flavoring agents, volatile oils, buffering agents, osmotically active agents (e.g. mannitol, xylitol, erythritol) and surfactants.
[0297] Compositions containing respirable or non-respirable dry particles of micronized active agent may be prepared by grinding the dry active agent with a mortar and pestle, and then passing the micronized composition through a 400 mesh screen to break up or separate out large agglomerates.
[0298] The particulate composition may optionally contain a dispersant which serves to facilitate the formation of an aerosol. A suitable dispersant is lactose, which may be blended with the active agent in any suitable ratio (e.g., a 1 to 1 ratio by weight).
[0299] The compounds of formula (I) may be synthesized according to procedures known in the art. A representative synthetic procedure is shown in the scheme below (scheme 1):
[0000]
[0000] These procedures are described in, for example, E. J. Cragoe, “The Synthesis of Amiloride and Its Analogs” (Chapter 3) in Amiloride and Its Analogs, pp. 25-36, incorporated herein by reference. Other methods of preparing the compounds are described in, for example, U.S. Pat. No. 3,313,813, incorporated herein by reference. See in particular Methods A, B, C, and D described in U.S. Pat. No. 3,313,813. Other methods useful for the preparation of these compounds, especially for the preparation of the novel HNR 3 R 4 fragment are described in, for example, U.S. Pat. No. 6,858,614, U.S. Pat. No. 6,858,615, and U.S. Pat. No. 6,903,105, incorporated herein by reference.
[0300] Scheme 1-2 are representative of, but not limited to, procedures used to prepare the Sodium Channel Blockers/Beta Adrenergic Agonists described herein.
[0000]
[0000]
[0301] Several assays may be used to characterize the compounds of the present invention. Representative assays are described below.
[0302] 1. In Vitro Measure of Epithelial Sodium Channel Block and Beta Agonist Activity
[0303] To assess the potency of epithelial sodium channel block and beta agonist activity each compound was tested using two separate experimental procedures with similar methodology.
[0304] To assess epithelial sodium channel blocker potency the compounds of the present invention involves the determination of lumenal drug inhibition of airway epithelial sodium currents measured under short circuit current (I SC ) using airway epithelial monolayers mounted in Ussing chambers. Cells obtained from freshly excised human, or dog airways are seeded onto porous 0.4 micrometer Transwell® Permeable Supports (Corning Inc. Acton, Mass.), cultured at air-liquid interface (ALI) conditions in hormonally defined media, and assayed for sodium transport activity (I SC ) while bathed in Krebs Bicarbonate Ringer (KBR) in Ussing chambers. All test drug additions are to the lumenal bath with approximately half-log dose additions (from 1×10 −11 M to 6×10 −5 M), and the cumulative change in I SC (decreases) recorded. All drugs are prepared in dimethyl sulfoxide as stock solutions at a concentration of approximately 1×10 −2 and stored at −20° C. Six preparations are typically run in parallel; one preparation per run incorporates 552-02 as a positive control. Before the start of the concentration-effect relationship propranolol, a non-selective beta agonist blocker, was applied to the lumenal bath (10 μM) to inhibit the beta agonist component of the designer multiple ligand (DML). All data from the voltage clamps are collected via a computer interface and analyzed off-line.
[0305] Concentration-effect relationships for all compounds are considered and analyzed Using GraphPad Prism version 3.00 for Windows, GraphPad Software, San Diego Calif. USA. IC 50 values, maximal effective concentrations, are calculated and compared to the 552-02 potency as a positive control.
[0306] To assess beta agonist activity the compounds of the present invention involves the determination of lumenal drug addition to promote airway epithelial anion currents measured under short circuit current (I SC ) using airway epithelial monolayers mounted in Ussing chambers. Cells obtained from freshly excised human, dog, or sheep airways are seeded onto porous 0.4 micron Transwell®Permeable Supports (Corning), cultured at air-liquid interface (ALI) conditions in hormonally defined media, and assayed for anion secretion (I SC ) while bathed in Krebs Bicarbonate Ringer (KBR) in Ussing chambers. All test drug additions are to the lumenal bath with approximately half-log dose additions (from 8×10 −10 M to 6.5×10 −5 M), and the cumulative change in I SC (excitation) recorded. All drugs are prepared in dimethyl sulfoxide as stock solutions at a concentration from 1×10 −1 to 1×10 −2 M and stored at −20° C. Six preparations are typically run in parallel; one preparation per run incorporates either formoterol, salmeterol, or another well recognized beta agonists as a positive control depending on the analog incorporated in the compound being tested. Before the start of the concentration-effect relationship 552-02 a potent sodium channel blocker was applied to the apical surface (1 μM) to eliminate changes in Isc caused by sodium absorption. All data from the voltage clamps are collected via a computer interface and analyzed off-line.
[0307] Concentration-effect relationships for all compounds are considered and analyzed Using GraphPad Prism version 3.00 for Windows, GraphPad Software, San Diego Calif. USA. EC 50 values, maximal effective concentrations, are calculated and compared to either formoterol or salbutamol as the positive control.
[0308] 2. In Vitro Assay of Compound Absorption and Biotransformation by Airway Epithelia
[0309] Airway epithelial cells have the capacity to metabolize drugs during the process of transepithelial absorption. Further, although less likely, it is possible that drugs can be metabolized on airway epithelial surfaces by specific ectoenzyme activities. Perhaps more likely as an ecto-surface event, compounds may be metabolized by the infected secretions that occupy the airway lumens of patients with lung disease, e.g. cystic fibrosis. Thus, a series of assays are performed to characterize any compound biotransformation (metabolism or conjugation) that results from the interaction of test compounds with human airway epithelia and/or human airway epithelial lumenal products.
[0310] In the first series of assays, the interaction of test compounds in KBR as an “ASL” stimulant are applied to the apical surface of human airway epithelial cells grown in the Transwell® Permeable Supports (Corning), insert system. For most compounds, metabolism or conjugation (generation of new species) is tested for using high performance liquid chromatography (HPLC) to resolve chemical species and the endogenous fluorescence properties of these compounds to estimate the relative quantities of test compound and novel metabolites. For a typical assay, a test solution (1 mL KBR, containing 100 μM test compound) is placed on the epithelial lumenal surface. Sequential 5 to 600 μl samples are obtained from the lumenal and serosal compartments respectively for HPLC analysis of (1) the mass of test compound permeating from the lumenal to serosal bath and (2) the potential formation of metabolites from the parent compound. From the HPLC data, the rate of and/or formation of novel metabolite compounds on the lumenal surface and the appearance of test compound and/or novel metabolite in the basolateral solution is quantitated based on internal standards. The data relating the chromatographic mobility of potential novel metabolites with reference to the parent compound are also quantitated.
[0311] To analyze the potential metabolism of test compounds by CF sputum, a “representative” mixture of expectorated CF sputum obtained from 10 CF patients (under IRB approval) has been collected. The sputum has been be solubilized in a 1:5 mixture of KBR solution with vigorous vortexing, following which the mixture was split into a “neat” sputum aliquot and an aliquot subjected to ultracentrifugation so that a “supernatant” aliquot was obtained (neat=cellular; supernatant=liquid phase). Typical studies of compound metabolism by CF sputum involve the addition of known masses of test compound to “neat” CF sputum and aliquots of CF sputum “supernatant” incubated at 37° C., followed by sequential sampling of aliquots from each sputum type for characterization of compound stability/metabolism by HPLC analysis as described above. As above, analysis of compound disappearance, rates of formation of novel metabolities, and HPLC mobilities of novel metabolites are then performed.
EXAMPLES
[0312] Having generally described this invention, a further understanding can be obtained by reference to certain specific examples which are provided herein for purposes of illustration only and are not intended to be limiting unless otherwise specified.
Preparation of Sodium Channel Blockers with Beta Agonist Activity
[0313] Materials and Methods. All reagents and solvents were purchased from Aldrich Chemical Corp. and used without further purification. NMR spectra were obtained on either a Bruker WM 360 ( 1 H NMR at 360 MHz and 13 C NMR at 90 MHz) or a Bruker AC 300 ( 1 H NMR at 300 MHz and 13 C NMR at 75 MHz). Flash chromatography was performed on a Flash Eluteθ system from Elution Solution (PO Box 5147, Charlottesville, Va. 22905) charged with a 90 g silica gel cartridge (40M FSO-0110-040155, 32-63 μm) at 20 psi (N 2 ). GC-analysis was performed on a Shimadzu GC-17 equipped with a Heliflex Capillary Column (Alltech); Phase: AT-1, Length: 10 meters, ID: 0.53 mm, Film: 0.25 micrometers. GC Parameters: Injector at 320° C., Detector at 320° C., FID gas flow: H 2 at 40 ml/min., Air at 400 ml/min. Carrier gas: Split Ratio 16:1, N 2 flow at 15 ml/min., N 2 velocity at 18 cm/sec. The temperature program is 70° C. for 0-3 min, 70-300° C. from 3-10 min, 300° C. from 10-15 min.
[0314] HPLC analysis was performed on a Gilson 322 Pump, detector UV/Vis-156 at 360 nm, equipped with a Microsorb MV C8 column, 100 A, 25 cm. Mobile phase: A=acetonitrile with 0.1% TFA, B=water with 0.1% TFA. Gradient program: 95:5 B:A for 1 min, then to 20:80 B:A over 7 min, then to 100% A over 1 min, followed by washout with 100% A for 11 min, flow rate: 1 ml/min.
Example 1
Synthesis of (R)-3,5-diamino-6-chloro-N—(N-{11-[2-(3-formamido-4-hydroxyphenyl)-2-hydroxyethylamino]undecyl}carbamimidoyl)pyrazine-2-carboxamide (15) (Scheme 1)
[0315]
1-(4-Benzyloxy-3-nitrophenyl)ethanone (2)
[0316] A mixture of 1-(4-hydroxy-3-nitrophenyl)ethanone (50.00 g, 276 mmol), sodium iodide (20.00 g, 133.4 mmol), potassium carbonate (115.00 g, 832.00 mmol), and benzyl bromide (43.00 mL, 362.00 mmol) in acetone (120 mL) was stirred under reflux for 16 h. The solids were removed by filtration and the filtrate concentrated by rotary evaporation. After this time the resulting residue was diluted with dichloromethane and insoluble inorganics were removed by filtration. The filtrate was concentrated in vacuo and the resulting residue was dissolved in hot chloroform. Hexanes were added to form a precipitate. The solids were collected by filtration to give benzyl ether 2 as a white solid (65.60 g, 87%): 1 H NMR (500 MHz, CDCl 3 ) δ 2.60 (s, 3H), 5.32 (s, 2H), 7.18 (d, 1H), 7.41 (m, 5H), 8.12 (dd, 1H), 8.44 (d, 1H).
1-(4-Benzyloxy-3-nitrophenyl)-2-bromoethanone (3)
[0317] Phenyltrimethylammonium tribromide (109.00 g, 290.00 mmol) was added to a solution of 1-(4-benzyloxy-3-nitrophenyl)ethanone (2) (65.60 g, 242.00 mmol) in anhydrous THF (600 mL) in three portions, and the reaction mixture was stirred at rt for 12 h. The solids were then collected by filtration and the filtrate concentrated. The product was precipitated from chloroform upon the addition of hexanes, then collected by filtration and dried under vacuum to give bromo ketone 3 as a light yellow solid (63.33 g, 75% yield): 1 H NMR (500 MHz, CDCl 3 ) δ 4.37 (s, 3H), 5.35 (s, 2H), 7.21 (d, 1H), 7.40 (m, 5H), 8.15 (dd, 1H), 8.49 (d, 1H).
1-(4-Benzyloxy-3-nitrophenyl)-2-bromo-1-(R)-ethanol (4)
[0318] A solution of BH 3 .THF in THF (1 M, 108.00 mL, 108.00 mmol) was added to a solution of 1-(4-benzyloxy-3-nitrophenyl)-2-bromoethanone (3) (63.30 g, 180.00 mmol) and R-methyl-CBS-oxazoborolidme (1 M in toluene, 36.00 mL, 36.00 mmol) in anhydrous THF (500 mL). The resulting reaction mixture was stirred at rt for 16 h. Methanol (250 mL) was then slowly added to quench the reaction. After removal of solvent by rotary evaporation, the resulting residue was purified by column chromatography (silica gel, a gradient of 70:30 to 100:0 dichloromethane/hexanes) to give the desired bromo alcohol 4 as a yellow, viscous oil (36.80 g, 75% yield): 1 H NMR (500 MHz, CDCl 3 ) δ 2.72 (d, 1H), 3.48 (dd, 1H), 3.59 (dd, 1H), 4.89 (m, 1H), 5.21 (s, 2H), 7.11 (d, 1H), 7.39 (m, 5H), 7.50 (dd, 1H), 7.87 (d, 1H).
N-[2-Benzyloxy-5-(2-bromo-1-(R)-hydroxyethyl)phenyl]formamide (5)
[0319] A Parr hydrogenator was charged with PtO 2 and 1-(4-benzyloxy-3-nitro-phenyl)-2-bromo-1-(R)-ethanol (4) (3.60 g, 10.22 mmol) dissolved in a mixed solvent of THF (25 mL) and toluene (25 mL); and the mixture shaken under an atmosphere of hydrogen at 55 psi at rt for 14 h. The hydrogen pressure was then released. To the mixture was added directly a mixture of formic acid (0.65 mL, 17.23 mmol) and acetic anhydride (1.10 mL, 11.65 mmol). The newly resulting mixture was stirred at rt for an additional 16 h. The catalyst was removed by filtration through a Celite pad and the filtrate was concentrated by rotary evaporation. The resulting residue was purified by column chromatography (silica gel, a gradient of 30:70 to 50:50 ethyl acetate/hexanes) to give the desired formamide 5 as a white solid (3.62 g, >99% yield): 1 H NMR (300 MHz, CDCl 3 ) δ 2.95 (s, 1H), 3.52 (m, 1H), 3.60 (m, 1H), 4.85 (m, 1H), 5.08 (s, 2H), 6.96 (d, 1H), 7.13 (dd, 1H), 7.39 (m, 5H), 7.88 (br s, 1H), 8.37 (dd, 1H).
tert-Butyl 11-aminoundecylcarbamate (7)
[0320] Using a syringe pump, a solution of di-tert-butyl dicarbonate (2.50 g, 11.45 mmol) in methanol (50 mL) was added to a stirred solution of undecane 1,11-diamine (6) (3.00 g, 16.10 mmol) and diisopropylethylamine (2.90 mL, 16.60 mmol) in methanol (200 mL) over 10 h, and the resulting reaction mixture was stirred at rt for 12 h. The reaction was then concentrated to a white solid. Purification by column chromatography (silica gel, 10:90 methanol/dichloromethane, then 20:80 (10% concentrated ammonium hydroxide in methanol)/dichloromethane) afforded the protected amine 7 (2.19 g, 67% yield) as a white solid: 1 H NMR (300 MHz, CD 3 OD) δ 1.30 (br s, 14H), 1.43 (br s, 13H), 2.61 (t, 2H), 3.00 (t, 2H).
Benzyl 11-(1-tert-butylamino)undecyl carbamate (8)
[0321] Benzylchloroformate (1.30 mL, 9.14 mmol) was added to a mixture of tert-butyl 11-aminoundecylcarbamate (7) (2.19 g, 7.65 mmol) in dichloromethane (40 mL) and 25% sodium carbonate in water (20 mL), and the resulting reaction mixture was stirred at ambient temperature for 3 h. After this time the reaction was extracted with dichloromethane (2×50 mL). The organic extracts combined, concentrated and placed under vacuum. Purification by column chromatography (silica gel, 10:90 methanol/dichloromethane, followed by a gradient of 5:95 to 10:90 (10% concentrated ammonium hydroxide in methanol)/dichloromethane) gave the desired diamine 8 (2.88 g, 92% yield) as a white solid: 1 H NMR (500 MHz, CDCl 3 ) δ 1.25-1.28 (m, 14H), 1.43-1.55 (m, 13H), 3.09-3.18 (m, 4H), 4.51 (br s, 1H), 4.70 (br s, 1H), 5.09 (s, 2H), 7.22-7.34 (m, 5H); m/z (ESI) 411 [C 26 H 38 N 2 O 2 +H] + .
Benzyl 11-aminoundecylcarbamate (9)
[0322] Diamine 8 (1.00 g, 2.45 mmol) was dissolved in methanolic hydrogen chloride (10 M, 10 mL) and stirred at ambient temperature for 2 h. After removal of solvent by rotary evaporation, the residue was dissolved in dichloromethane/methanol (2:1, v/v) and triethylamine (0.40 mL, 2.84 mmol) was added. The solution was stirred for 30 min, and then the solvent was removed under vacuum. The residue was carried into the next reaction without purification or characterization.
Benzyl 11-(benzylamino)undecylcarbamate (11)
[0323] Benzaldehyde 10 (0.25 mL, 2.47 mmol) was added to a mixture of carbamate 23 (0.76 g, 2.36 mmol), sodium sulfate (100 mg) and ethereal hydrogen chloride (1 M, 2 drops) in dichloroethane (25 mL). The reaction was stirred at ambient temperature for 14 h, then sodium triacetoxyborohydride (0.75 g, 3.54 mmol) was added and stirring continued for an additional 1 h. The reaction was quenched by the addition of saturated aqueous sodium bicarbonate and extracted with dichloromethane (3×25 mL). The combine organics were concentrated under vacuum, then purified by column chromatography (silica, 10:90 (10% concentrated ammonium hydroxide in methanol)/dichloromethane) to give benzylamine 11 (0.44 mg, 59% yield) as a white solid: 1 H NMR (500 MHz, CD 3 OD) δ 1.29 (m, 14H), 1.46-1.55 (m, 2H), 2.61 (t, 2H), 3.09 (t, 2H), 3.78 (s, 2H), 4.59 (s, 1H), 5.05 (s, 2H), 7.22-7.34 (m, 10H); m/z (ESI) 411 [C 26 H 38 N 2 O 2 +H] + .
(R)-Benzyl 11-(benzyl{2-[4-(benzyloxy)-3-formamidophenyl]-2-hydroxyethyl}-amino)undecylcarbamate (12)
[0324] Benzylamine 11 (0.32 g, 0.79 mmol) was added to a suspension of bromoalcohol 19 (0.33 g, 0.95 mmol) and potassium carbonate (0.27 g, 1.98 mmol) in isopropanol (7 mL). The suspension was heated to 83° C. for 40 h. After this time the mixture was cooled, the solid was removed by vacuum filtration and the filtrate was concentrated under vacuum. The resulting yellow solid was subjected to column chromatography (silica, a gradient of 20:80 to 50:50 ethyl acetate/hexanes) to afford the desired product 12 (0.28 g, 52% yield) as a clear oil: 1 H NMR (300 MHz, CD 3 OD) δ 1.19-1.72 (m, 18H), 2.48-2.73 (m, 2H), 3.04-3.08 (m, 2H), 3.61-3.84 (m, 2H), 4.66 (t, 1H), 5.04 (br s, 2H), 5.18 (br s, 2H), 6.99-7.67 (m, 18H), 8.22-8.32 (m, 1H);
(R)—N-{5-[2-(11-Aminoundecylamino)-1-hydroxyethyl]-2-hydroxyphenyl}formamide (13)
[0325] Aminoalcohol 12 (028 g, 0.41 mmol) was dissolved in ethanol (10 mL). Following the standard hydrogenation procedure, palladium dihydroxide (20% on carbon, 50% wet) was added. The reaction mixture was stirred for 48 h at ambient temperature under atmospheric hydrogen pressure. The catalyst was removed by filtration through diatomaceous earth and the filtrate was concentrated. Drying under vacuum gave 27 (0.12 g, 77% yield) as an orange oil: 1 H NMR (300 MHz, CD 3 OD) δ 1.19-1.72 (m, 18H), 2.58-2.89 (m, 4H), 3.51-3.72 (m, 1H), 4.74 (m, 1H), 6.72-6.81 (m, 1H), 6.91-7.06 (m, 1H), 8.02-8.08 (m, 1H), 8.29 (br, 1H).
(R)-3,5-Diamino-6-chloro-N—(N-{11-[2-(3-formamido-4-hydroxyphenyl)-2-hydroxyethylamino undecyl}carbamimidoyl)pyrazinecarboxamide (15)
[0326] Diisopropylethylamine (0.07 mL, 0.40 mmol) and 1-(3,5-diamino-6-chloropyrazine-2-carbonyl)-2-methylisothiourea hydriodide (125 mg, 0.32 mmol) were sequentially added to a solution of amine 14 (116 mg, 0.32 mmol) in ethanol (5 mL). The reaction mixture was heated to 75° C. for 3.5 h. After this time it was cooled and concentrated under vacuum. The resulting residue was purified by column chromatography (silica, a gradient of 10:90 to 80:20 (10% concentrated ammonium hydroxide/methanol)/dichloromethane) affording the crude product. Further purification by prep HPLC [10 to 90% acetonitrile in water (both with 0.01% TFA added) over 40 minutes] and then prep TLC (silica, 10:90 to 30:70 (10% concentrated ammonium hydroxide/methanol)/dichloromethane gave product 15 (26 mg, 14%) as a brown solid: mp 112-116° C.; 1 H NMR (500 MHz, CD 3 OD) δ 1.27-1.49 (m, 15H), 1.61-1.74 (m, 4H), 2.91-3.08 (m, 4H), 6.85-6.87 (m, 1H), 7.02-7.05 (m, 1H), 8.01-8.02 (m, 1H), 8.31 (br s, 1H); m/z (ESI) 578 [C 26 H 40 ClN 9 O 4 +H] + .
Example 2
[0327] Compound 15, ENaC blocking Activity, IC50(nM)=27.8 (39× Amiloride)
Beta Agonist Activity, EC50(nM)=206 (fomoterol=5.3)
Example 3
[0328] Compound 16 ENaC blocking Activity, IC50(nM)=6.5(158× Amiloride)
[0000]
Synthesis of 3,5-diamino-6-chloro-N—(N—((S)-1-(R)-2-(3-formamido-4-hydroxyphenyl)-2-hydroxyethylamino)dodecyl)carbamimidoyl)pyrazine-2-carboxamide di-L-lactate [26a and 26b] (Scheme 2)
[0329]
11-(Benzyloxycarbonylamino)undecanoic acid (18)
[0330] To a suspension of 11-aminoundecanoic acid (17) in 1:1 water/dioxane (160 mL total) was added K 2 CO 3 (10.28 g, 74.51 mmol) followed by the slow addition over 30 min of benzylchloroformate (CbzCl, 4.55 mL, 32.29 mmol), and the mixture was stirred at room temperature for 2 h. The solid was then removed by filtration, washed with water (3×30 mL) and dried in a vacuum oven at 40° C. for 72 h to afford a white solid 18 (2.91 g, 35% yield): 1 H NMR (500 MHz, CD 3 OD) δ 1.36 (m, 12H), 1.50 (m, 2H), 1.62 (m, 2H), 2.18 (m, 2H), 3.08 (m, 2H), 5.14 (s, 2H), 7.38 (m, 511H); m/z (ESI) 336 [M+H] + .
Methyl 11-(benzyloxycarbonylamino)undecanoate (19)
[0331] A suspension of 18 (2.91 g, 8.68 mmol), Cs 2 CO 3 (4.25 g, 13.02 mmol) and DMF (anhydrous, 40 mL) was stirred at room temperature for 1.5 h. To the mixture was then added methyl iodide (0.83 mL, 13.02 mmol), and stirring was continued for an additional 3 h at the ambient temperature. The mixture was then partitioned between water (150 mL) and dichloromethane (150 mL), aqueous layer was separated and washed with dichloromethane (3×300 mL).
[0332] Organics were combined, dried over anhydrous Na 2 SO 4 , concentrated and further dried under high vacuum overnight to afford the desired methyl ester 19 (3.41 g, quant yield): 1 H NMR (500 MHz, CDCl 3 ) δ 1.26 (m, 12H), 1.47 (m, 2H), 1.52 (m, 2H), 2.28 (m, 2H), 3.16 (m, 2H), 3.66 (s, 3H), 5.10 (s, 2H), 7.32 (m, 5H); m/z (ESI) 350 [M+H] + .
Benzyl 11-(methoxy(methyl)amino)-11-oxoundecylcarbamate (20)
[0333] A solution of 19 (2.25 g, 6.44 mmol), methyl methoxyamine hydrochloride (1.26 g, 12.88 mmol) and THF (anhydrous, 30 mL) was cooled to −15 to −20° C. with an ice/methanol bath containing a few pieces of dry ice. To this cold solution was added dropwise i-PrMgCl (3M solution in pentane, 11.27 mL, 22.54 mmol) over 15 min and temperature was then raised to −10° C. and stirring continued at the temperature for additional 2 h. After this time the reaction was quenched by the slow addition of saturated aqueous NH 4 Cl (50 mL). The aqueous layer was separated and washed with dichloromethane (2×50 mL). Organics were combined, dried over anhydrous Na 2 SO 4 , concentrated and further dried under high vacuum overnight to afford the desired product 20 (2.04 g, 84% yield) as a colorless, viscous oil: 1 H NMR (300 MHz, CDCl 3 ) δ 1.27 (m, 12H), 1.48 (m, 2H), 1.60 (m, 2H), 2.40 (m, 2H), 3.18 (m, 5H), 3.68 (s, 3H), 5.09 (s, 2H), 7.34 (m, 5H); m/z (ESI) 379 [M+H] + .
Benzyl 11-oxododecylcarbamate (21)
[0334] To a solution of 20 (1.11 g, 2.94 mmol) in THF (anhydrous, 10 mL) and cooled in an ice bath was added dropwise MeMgCl (3 M solution in diethyl ether, 3.92 mL, 11.75 mmol) over 10 min, and stirring continued at 0° C. for 6 h. The reaction was quenched by the slow addition of methanol (10 mL), and then concentrated under vacuum. The residue was chromatographed (silica gel, a gradient of 0:100 to 18:82 ethyl acetate/hexanes) to afford the desired product 21 (0.78 g, 80% yield) as a white solid: 1 H NMR (300 MHz, CDCl 3 ) δ 1.26 (m, 12H), 1.49-1.57 (m, 4H), 2.13 (s, 3H), 2.41 (m, 2H), 3.19 (m, 5H), 5.09 (s, 2H), 7.34 (m, 5H); m/z (ESI) 334 [M+H] + .
(R)-Benzyl 11-(2-(3-formamido-4-hydroxyphenyl)-2-hydroxyethylamino)dodecyl-carbamate (23)
[0335] A solution containing compound 19 (0.43 g, 1.29 mmol) and (R)—N-(5-(2-amino-1-hydroxyethyl)-2-benzyloxy)phenyl)formamide 22 (0.27 g, 1.35 mmol) in methanol (anhydrous, 6 mL) was stirred at room temperature for 4 h. To this solution was then added NaCNBH 3 (0.24 g, 3.87 mmol) in one portion, and the mixture was continuously stirred at room temperature overnight. After this time, the mixture was concentrated and the residue was subjected to chromatography (a gradient of 0:100 to 10:90 methanol/dichloromethane) to afford the desired product 23 (0.54 g, 82% yield): 1 H NMR (300 MHz, CD 3 OD) δ 1.31 (m, 15H), 1.48-1.58 (m, 4H), 1.75 (m, 2H), 3.10 (m, 5H), 4.83 (m, 1H), 5.09 (s, 2H), 6.89 (d, 1H), 7.04 (d, 1H), 7.34 (m, 6H), 8.12 (s, 1H), 8.32 (s, 1H); m/z (ESI) 514 [M+H] + .
(R)—N-(5-(2-(12-Aminododecan-2-ylamino)-1-hydroxyethyl)-2-hydroxyphenyl)-formamide (24)
[0336] A mixture of compound 23 (0.54 g, 1.05 mmol) dissolved in methanol (30 mL) and palladium catalyst (0.15 g, 10% Pd on carbon, 50% we) was stirred overnight at room temperature under one atmospheric hydrogen pressure. The catalyst was removed by filtration and washed with methanol (3×10 mL). The filtrate and washings were combined and concentrated under vacuum to complete dryness, affording the desired product 24 (0.40 g, 91% yield) as an off-white solid: 1 H NMR (300 MHz, CD 3 OD) a 1.31 (m, 15H), 1.48-1.58 (m, 4H), 1.75 (m, 2H), 260-2.80 (m, 5H), 4.66 (m, 1H), 5.09 (s, 2H), 6.82 (d, 1H), 7.00 (d, 1H), 8.02 (s, 1H), 8.30 (s, 1H); m/z (ESI) 380 [M+H] + .
3,5-Diamino-6-chloro-N—(N—((R)-1-((R)-2-(3-formamido-4-hydroxyphenyl)-2-hydroxyethylamino)dodecyl)carbamimidoyl)pyrazine-2-carboxamide (25a) and 3,5-Diamino-6-chloro-N—(N—((S)-11-(R)-2-(3-formamido-4-hydroxyphenyl)-2-hydroxyethylamino)dodecyl)carbamimidoyl)pyrazine-2-carboxamide (25b)
[0337] A suspension of compound 24 (0.40 g, 1.05 mmol), Hunig's base (0.89 mL, 5.27 mmol) and ethanol (14 mL) was heated at 70° C. for 30 min, and then 1-(3,5-diamino-6-chloropyrazine-2-carbony)-2-methylisothiourea hydriodide (, 0.43 g, 1.17 mmol) was added. The resulting solution was continuously stirred at that temperature for an additional 3 h before it was cooled to room temperature. The un-dissolved solid was removed by filtration, and the filtrate was concentrated. The resulting residue was subjected to column chromatography eluting with a mixture of methanol (0-16%), concentrated ammonium hydroxide (0-1.6%) and dichloromethane (100-83.4%) to afford a mixture of 25a and 25b (0.12 g total, 20% overall yield): 1 H NMR (500 MHz, CD 3 OD) δ 1.12 (m, 6H), 1.38-1.50 (m, 30H), 1.57 (m, 4H), 1.73 (m, 4H), 2.72-2.90 (m, 6H), 3.33 (m, 4H), 4.60-4.70 (m, 2H), 6.84 (d, 2H), 7.04 (d, 2H), 8.10 (s, 2H), 8.30 (s, 2H); m/z (ESI) 592 [M+H] + . This material was subjected to further chromatography by prep TLC plates eluting several times with a mixture of methanol (0-22%), concentrated ammonium hydroxide (0-2.2%) and dichloromethane (100-75.8%) to afford 25a (42 mg) and 25b (56 mg), respectively, both as yellow solids. The stereochemistry of the chiral methyl groups in 68a and 69a were arbitrarily assigned.
3,5-Diamino-6-chloro-N—(N—((R)-11-(R)-2-((3-formamido-4-hydroxyphenyl)-2-hydroxyethylamino)dodecyl)carbamimidoyl)pyrazine-2-carboxamide di-L-lactate [26a]
[0338] L-lactic acid (13.7 mg, 0.14 mmol) was added to a suspension of compound 25a (42 mg, 0.15 mmol) in absolute ethanol (3 mL). The mixture was stirred at room temperature for 1 h and turned to a clear solution. The solution was then concentrated under vacuum and completely dried to afford 26a (46 mg, quant yield) as a brown, viscous oil: 1 H NMR (500 MHz, DMSO-d 6 ) δ 1.18-1.24 (m, 21H), 1.40-1.75 (m, 6H), 2.96 (m, 2H), 3.07 (m, 1H), 3.28 (m, 2H), 4.10 (m, 2H), 4.82 (m, 1H), 6.08 (br s, 1H), 6.84 (d, 1H), 7.04 (d, 1H), 7.48 (br s, 2H), 8.16 (s, 1H), 8.30 (s, 1H), 8.88-9.10 (br s, 2H), 9.66 (s, 1H), 9.96 (br s, 1H); m/z (ESI) 592 [M+H] + .
3,5-Diamino-6-chloro-N—(N—((S)-11-(R)-2-((3-formamido-4-hydroxyphenyl)-2-hydroxyethylamino)dodecyl)carbamimidoyl)pyrazine-2-carboxamide di-L-lactate [26b]
[0339] Compound 26b (44 mg, quant yield), a brown solid, was prepared from 25b in a similar method to 68a: mp 86-88° C. (decomposed); 1 H NMR (500 MHz, DMSO-d 6 ) δ 1.11 (d, 3H), 1.20 (s, 6H), 1.28-1.36 (m, 12H), 1.48-1.70 (m, 6H), 2.78-3.26 (m, 5H), 3.92 (m, 2H), 4.64 (m, 1H), 6.72-6.82 (br s, 2H), 6.84 (d, 1H), 6.92 (d, 1H), 8.09 (s, 1H), 8.28 (s, 1H), 9.59 (br s, 1H); m/z (ESI) 592 [M+H] + .
Methods
Pharmacological Effects and Mechanism of Action of the Drug in Animals
[0340] The effect of compounds for enhancing mucociliary clearance (MCC) can be measured using an in vivo model described by Sabater et al., Journal of Applied Physiology, 1999, 87(6) pp. 2191-2196, incorporated herein by reference.
Animal Preparation.
[0341] Adult ewes up to 75 Kg were placed in a restraint and positioned upright using a specialized body harness. The heads of the animals were immobilized, and local anesthesia of the nasal passage was provided (2% lidocaine) prior to nasal intubation (7.5 mm-I.D. endotracheal tube (ETT) (Mallinckrodt Medical, St. Louis, Mo.). The cuff of the ETT was placed just below the vocal cords. After intubation, the animals were allowed to equilibrate for approximately 20 min before MCC measurements began.
Sheep MCC In Vivo Measurement:
[0342] Aerosols of sulfur colloid radiolabled with technetium ( 99m Tc—SC 3.1 mg/mL, ˜10-15 mCi) were generated by a Raindrop Nebulizer (Nellcor Puritan Bennett, Pleasanton, Calif.) which produces a median aerodynamic droplet diameter of 3.6 μm. The nebulizer was connected to a dosimeter system consisting of a solenoid valve and a source of compressed air (20 psi). The output of the nebulizer was directed into a T piece, with one end attached to a respirator (Harvard apparatus, South Natick, Mass.). The system was activated for 1 second at the onset of the respirator's inspiratory cycle. The tidal volume was set at 300 mL, with an inspiratory-to-expiratory ratio of 1:1, and a rate of 20 breaths/min, to maximize central airway deposition. The sheep breathed the 99m Tc—SC aerosol for up to 5 min. Following tracer deposition, a gamma camera was used to measure the clearance of 99m Tc—SC from the airways. The camera was positioned above the animal's back with the sheep in its natural upright position in the harness. The field of the image was perpendicular to the animal's spinal cord. External radiolabled markers were placed on the sheep to facilitate proper alignment of the gamma camera. A region of interest was traced over the image corresponding to the right lung of the sheep and counts were recorded. The counts were corrected for decay and expressed as a percentage of radioactivity present in the baseline image. The left lung was excluded from the analysis because the outline of the lung was superimposed over the stomach and counts could be affected by swallowed 99m Tc—SC-labeled mucus. All deposition images were stored on a computer interfaced to the gamma camera. The protocol included a baseline deposition image obtained immediately post radio-aerosol administration. After acquisition of baseline images, either 4 mL of H 2 O (vehicle), formoterol (3 mM), or novel chemical entity (3 mM) were aerosolized using the Pari LC JetPlus nebulizer to free-breathing sheep using two separate protocols. Protocol 1, acquired data immediately after dosing (time 0 to 1 hour), and indicated the immediate physiological response ‘short-term efficacy’ protocol 2, acquired data 4 hours post dosing indicated compound durability and ‘long-term efficacy’. The nebulizer had a flow rate of 8 L/min and the time to deliver the solution was 10-12 min. On the completion of compound administration, the animal was immediately extubated to prevent false elevations in counts due to aspiration of excess 99m Tc—SC-labeled mucus from the ETT. Serial measurements of 99m Tc—SC retained in the lung were obtained over a 1 hour period at 5 min intervals. A washout period of at least 7 days (half life of 99m TC=6 h) separated studies with the different agents.
Statistical Analysis:
[0343] Data from the in vivo sheep MCC assays were analyzed using a two way ANOVA with repeated measures, followed by slope analysis of the linear regression of the retention vs time plot using an ANOCOVA to compare slopes, and if needed a multiple comparison test (Newman-Keuls). The percent activity retained (post 4 hours) was calculated by dividing the slope value from protocol 2 by the slope value obtained in protocol 1 and multiplying by 100%.
Animal Preparation:
[0344] Adult ewes (ranging in weight from 25 to 35 kg) were restrained in an upright position in a specialized body harness adapted to a modified shopping cart. The animals' heads were immobilized and local anesthesia of the nasal passage was induced with 2% lidocaine. The animals were then nasally intubated with a 7.5 mm internal diameter endotracheal tube (ETT). The cuff of the ETT was placed just below the vocal cords and its position was verified with a flexible bronchoscope. After intubation the animals were allowed to equilibrate for approximately 20 minutes prior to initiating measurements of mucociliary clearance.
Administration of Radio-Aerosol:
[0345] Aerosols of 99m Tc-Human serum albumin (3.1 mg/ml; containing approximately 20 mCi) were generated using a Raindrop Nebulizer which produces a droplet with a median aerodynamic diameter of 3.6 t m . The nebulizer was connected to a dosimetry system consisting of a solenoid valve and a source of compressed air (20 psi). The output of the nebulizer was directed into a plastic T connector; one end of which was connected to the endotracheal tube, the other was connected to a piston respirator. The system was activated for one second at the onset of the respirator's inspiratory cycle. The respirator was set at a tidal volume of 500 mL, an inspiratory to expiratory ratio of 1:1, and at a rate of 20 breaths per minute to maximize the central airway deposition. The sheep breathed the radio-labeled aerosol for 5 minutes. A gamma camera was used to measure the clearance of 99m Tc-Human serum albumin from the airways. The camera was positioned above the animal=s back with the sheep in a natural upright position supported in a cart so that the field of image was perpendicular to the animal=s spinal cord. External radio-labeled markers were placed on the sheep to ensure proper alignment under the gamma camera. All images were stored in a computer integrated with the gamma camera. A region of interest was traced over the image corresponding to the right lung of the sheep and the counts were recorded. The counts were corrected for decay and expressed as percentage of radioactivity present in the initial baseline image. The left lung was excluded from the analysis because its outlines are superimposed over the stomach and counts can be swallowed and enter the stomach as radio-labeled mucus.
Treatment Protocol (Assessment of Activity at T-Zero):
[0346] A baseline deposition image was obtained immediately after radio-aerosol administration. At time zero, after acquisition of the baseline image, vehicle control (distilled water), positive control (amiloride), or experimental compounds were aerosolized from a 4 ml volume using a Pari LC JetPlus nebulizer to free-breathing animals. The nebulizer was driven by compressed air with a flow of 8 liters per minute. The time to deliver the solution was 10 to 12 minutes. Animals were extubated immediately following delivery of the total dose in order to prevent false elevations in counts caused by aspiration of excess radio-tracer from the ETT. Serial images of the lung were obtained at 15-minute intervals during the first 2 hours after dosing and hourly for the next 6 hours after dosing for a total observation period of 8 hours. A washout period of at least 7 days separated dosing sessions with different experimental agents.
[0000] Treatment Protocol (Assessment of Activity at t−4 Hours):
[0347] The following variation of the standard protocol was used to assess the durability of response following a single exposure to vehicle control (distilled water), positive control compounds (amiloride or benzamil), or investigational agents. At time zero, vehicle control (distilled water), positive control (amiloride), or investigational compounds were aerosolized from a 4 ml volume using a Pari LC JetPlus nebulizer to free-breathing animals. The nebulizer was driven by compressed air with a flow of 8 liters per minute. The time to deliver the solution was 10 to 12 minutes. Animals were restrained in an upright position in a specialized body harness for 4 hours. At the end of the 4-hour period animals received a single dose of aerosolized 99m Tc-Human serum albumin (3.1 mg/ml; containing approximately 20 mCi) from a Raindrop Nebulizer. Animals were extubated immediately following delivery of the total dose of radio-tracer. A baseline deposition image was obtained immediately after radio-aerosol administration. Serial images of the lung were obtained at 15-minute intervals during the first 2 hours after administration of the radio-tracer (representing hours 4 through 6 after drug administration) and hourly for the next 2 hours after dosing for a total observation period of 4 hours. A washout period of at least 7 days separated dosing sessions with different experimental agents.
Statistics:
[0348] Data were analyzed using SYSTAT for Windows, version 5. Data were analyzed using a two-way repeated ANOVA (to assess overall effects), followed by a paried t-test to identify differences between specific pairs. Significance was accepted when P was less than or equal to 0.05. Slope values (calculated from data collected during the initial 45 minutes after dosing in the t-zero assessment) for mean MCC curves were calculated using linear least square regression to assess differences in the initial rates during the rapid clearance phase.
[0349] Obviously, numerous modifications and variations of the present invention are possible in light of the above teachings. It is therefore to be understood that within the scope of the appended claims, the invention may be practiced otherwise than as specifically described herein. | The present application provides sodium channel blockers exemplified by the following structure:
The compounds of the invention useful for treating chronic bronchitis, cystic fibrosis, sinusitis, vaginal dryness, dry eye, Sjogren's disease, distal intestinal obstruction syndrome, dry skin, esophagitis, dry mouth (xerostomia), nasal dehydration, ventilator-induced pneumonia, asthma, primary ciliary dyskinesia, otitis media, chronic obstructive pulmonary disease, emphysema, pneumonia, constipation, and chronic diverticulitis, for example. | 2 |
BACKGROUND
[0001] In the imaging industry, there is a growing market for the remanufacture and refurbishing of various types of replaceable imaging components such as toner cartridges, ink cartridges, and the like. Imaging cartridges, once spent, are unusable for their originally intended purpose. Without a refurbishing process, these cartridges would simply be discarded, even though the cartridge itself may still have potential life. As a result, techniques have been developed to remanufacture imaging cartridges. These processes may entail, for example, the disassembly of the various structures of the cartridge, replacing toner or ink, cleaning, adjusting or replacing any worn components and reassembling the cartridge.
[0002] Some imaging cartridges may include a chip having a memory device which is used to store data related to the cartridge or an imaging device, such as a printer, for example. The printer reads this data to determine certain printing parameters and communicate information to the user. For example, the memory may store the model number of the cartridge so that the printer may recognize the cartridge as one which is compatible with that particular printer. Additionally, by way of example, the cartridge memory may store the number of pages that can be expected to be printed from the cartridge during a life cycle of the cartridge and other useful data. The printer may also write certain data to the memory device, such as the amount of ink or toner remaining in the cartridge. Other data stored in the cartridge may relate to the usage history of the imaging cartridge.
[0003] It is often necessary to provide a replacement chip in order to remanufacture an imaging cartridge. Remanufacturers have developed “dedicated” replacement chips, i.e. chips that mimic an original equipment manufacture's (OEM) chip and are designed to be used for a specific imaging cartridge. Remanufactures have also developed “universal” chips which are chips that may be used with different imaging cartridges of different models. Additionally, remanufactures have developed “multibrand” chips which may be used on imaging cartridges sold by different manufacturers. Remanufacturers have also developed “multiregion” chips which are chips that work in more than one geographic region even though the OEM has regionalized printers.
[0004] It is desirable for the remanufacturer to test chips before placing them onto imaging cartridges. This allows the remanufacturer to verify that chip is suitable for the cartridge type. Also, this allows the remanufacturer to verify the maker of the chip and whether the chip contains virgin data or non-virgin data. U.S. Pat. No. 7,971,497 discloses a chip verifier that enables a remanufacturer to verify if the new ink jet chips attached to the remanufactured ink jet cartridges are new ink jet chips, if the new ink jet chips attached to the remanufactured ink jet cartridges were manufactured by a predetermined manufacturer of new ink jet chips, if the new ink jet chips attached to the remanufactured ink jet cartridges are functional, and if the new ink jet chips attached to the remanufacture ink jet cartridges are a predetermined type of new ink jet chip. This patent is incorporated by reference.
SUMMARY
[0005] The present method and system allows for a chip to be verified by a potential user. The chip may be a replacement intended to be used on a remanufactured imaging component. Alternatively the chip may be any other type of semiconductor chip and may be intended to be used on a newly manufactured imaging component.
[0006] The method includes verifying a chip by receiving a read command, receiving a write command, writing data to a test area in response to the write command, and transmitting data in response to the read command. The transmitted data is used to validate the chip as a proper chip.
[0007] By implementing this method a chip can be verified to determine if it is suitable for its intended use. For example, a chip can be verified as a suitable replacement chip for a remanufactured imaging cartridge.
[0008] In another embodiment the method includes verifying a chip by sending a a sync signal to the chip, sending a dummy word having a valid read command to the chip, sending a first value to the chip, sending a second value to the chip, sending a third value to the chip, sending a fourth value to the chip, and checking for a response from the chip. The chip responds with a sync signal and four values if the chip has been verified and the chip does not respond if it has not been verified.
[0009] The methods can be performed using a standalone chip verifier. Alternatively, the methods can be performed within the imaging device or by another suitable means or device.
[0010] These and other features and objects of the invention will be more fully understood from the following detailed description of the embodiments, which should be read in light of the accompanying drawings.
[0011] In this regard, before explaining at least one embodiment of the invention in detail, it is to be understood that the invention is not limited in its application to the details of construction and to the arrangements of the components set forth in the description or illustrated in the drawings. The invention is capable of other embodiments and of being practiced and carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein, as well as the abstract, are for the purpose of description and should not be regarded as limiting.
[0012] As such, those skilled in the art will appreciate that the conception upon which this disclosure is based may readily be used as a basis for designing other structures, methods, and systems for carrying out the several purposes of the present invention. It is important, therefore, that the claims be regarded as including such equivalent constructions insofar as they do not depart from the spirit and scope of the present invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] The accompanying drawings, which are incorporated in and form a part of the specification, illustrate embodiments of the present invention and, together with the description, serve to explain the principles of the invention;
[0014] FIG. 1 shows a perspective view of a prior art inkjet remanufacturing chip verifier and exemplary inkjet chips in accordance with the present invention; and
[0015] FIG. 2 shows a functional block diagram of a prior art inkjet remanufacturing chip verifier in accordance with the present invention.
DETAILED DESCRIPTION
[0016] The following detailed description of preferred embodiments refers to the accompanying drawings which illustrate specific embodiments of the invention. In the discussion that follows, specific systems and techniques for repairing or remanufacturing an inkjet cartridge including a memory element are disclosed. Other embodiments having different structures and operations for the repair of other types of replaceable imaging components and for various types of imaging devices do not depart from the scope of the present invention.
[0017] FIG. 1 illustrates a perspective view of an inkjet remanufacturing chip verifier 100 in accordance with the present invention. Also shown in FIG. 1 are exemplary remanufactured inkjet cartridges 150 and 160 . The inkjet cartridge 150 includes an inkjet chip 152 held in a recess. The inkjet chip 152 includes contacts 154 for communicating with a printer. The inkjet cartridge 160 includes an inkjet chip 162 having contacts 164 . The inkjet chip 162 is held in a slot 166 when attached to the inkjet cartridge 160 . These new inkjet chips are placed on the used inkjet cartridges 150 and 160 by a remanufacturer when the inkjet cartridges are refilled with ink and refurbished. The new inkjet chips typically include memory and other circuitry to control communication. The data stored in memory of the inkjet chips may include cartridge ink color, cartridge type, date manufactured, cartridge install date, cartridge expiration date, manufacturer name, and ink usage data, for example.
[0018] The inkjet remanufacturing chip verifier 100 includes a housing 102 enclosing circuitry described in greater detail below. A user interface may include a one or more input devices 104 that are utilized by a user to control the operation of the inkjet remanufacturing chip verifier 100 , or enter data, commands and the like. The input devices 104 may include switches, buttons, a keypad, a microphone, a data input port and the like. The user interface may also include one or more output devices 106 that are utilized to communicate with the user. The output devices 106 may include a display, light emitting diodes (LED), a speaker, data output port and the like. For inkjet chips which communicate directly using one or more contacts or pads (such as inkjet chips 150 and 160 ), the inkjet remanufacturing chip verifier 100 includes one or more contacts 108 which are used to communicatively connect to the contacts of the inkjet chip in order to transmit data to and receive data from the inkjet chip. Contacts 108 are disposed along a probe tip 114 of the inkjet remanufacturing chip verifier 100 and are adapted for engaging the contacts 164 of the inkjet chip 162 when the inkjet chip is disposed in the slot 166 . An extension element 112 including extension pins 110 may be attached to the probe tip 114 to allow the inkjet remanufacturing chip verifier 100 to access the contacts of inkjet chips which are held in a recess, such as contacts 154 of inkjet chip 152 .
[0019] For inkjet chips which communicate utilizing radio frequency (RF), an RF antenna, rather than contacts 108 , may be used in conjunction with appropriate circuitry to allow the inkjet remanufacturing chip verifier 100 to communicate with such devices.
[0020] FIG. 2 shows a functional block diagram of the inkjet remanufacturing chip verifier 100 in accordance with the present invention. The inkjet remanufacturing chip verifier 100 includes processing circuitry 200 or controller communicatively connected to chip input/output (I/O) circuitry 202 and a user interface 204 . The user interface 204 preferably comprises an output device 208 , such as a display or LED, for example, and an input device 206 , such as a keypad, for example.
[0021] The processing circuitry 200 includes memory 210 which may suitably comprise both volatile memory and nonvolatile memory for storing data and programming code controlling the operation of the inkjet remanufacturing chip verifier 100 . The input/output (I/O) circuitry 202 is communicatively connected to external contacts 212 and provides the appropriate components and electronic interface to allow the processing circuitry 200 to communicate with the cartridge memory element through the contacts 212 . Electrical power for the operation of the inkjet remanufacturing chip verifier 100 may be suitably provided by one or more batteries, a connection to an external DC source and/or a connection to an AC power source.
[0022] The processing circuitry 200 controls the operation of the inkjet remanufacturing chip verifier 100 and performs a variety of operations, as described in greater detail below. The processing circuitry 200 may be suitably implemented as a custom or semi-custom integrated circuit, a programmable gate array, a microprocessor executing instructions from memory, a microcontroller, or the like, for example. The processing circuitry 200 controls the reading of data from the inkjet chip and analysis of that data. The processing circuitry 200 controls the user interface 204 , receiving commands and data from the input devices 206 and outputting data, such as analysis results, on the output device 208 .
[0023] The inkjet remanufacturing chip verifier 100 may be used as a part of a remanufacturing production line in which used inkjet cartridges are refurbished, filled with ink and provided with a new inkjet chip. At the end of the remanufacturing line (after the new inkjet chip has been attached to the remanufactured inkjet cartridge), the inkjet remanufacturing chip verifier 100 may be used to verify certain characteristics of the new inkjet chips, thereby insuring, among other things, that the correct inkjet chip was attached to the remanufactured inkjet cartridge. A user of the inkjet remanufacturing chip verifier 100 may use the input device 206 of the user interface 204 to select a particular type of chip to verify.
[0024] By reading data from the memory of the inkjet chip and comparing that read inkjet chip data to reference inkjet chip data stored in the memory 210 , the processing circuitry 200 of the inkjet remanufacturing chip verifier 100 may verify, for example, if the inkjet chip is new chip and has not been used, if the inkjet chip was manufactured by a particular manufacturer of inkjet chips, if the inkjet chip is functional and if the inkjet chip is a particular type of inkjet chip. The reference inkjet chip data stored in the memory 210 may include inkjet chip data for a plurality of inkjet chip types, allowing the user to instruct the inkjet remanufacturing chip verifier 100 to determine whether or not a particular chip is present, or determine based the plurality of reference inkjet chip data, what type of chip is present. The reference inkjet chip data may suitably comprise a copy of the data expected to be stored in the memory of the inkjet chips.
[0025] The processing circuitry of the inkjet remanufacturing chip verifier 100 may further reject during the process of remanufacturing the ink jet cartridges: ink jet chips attached to remanufactured ink jet cartridges which have been previously used, ink jet chips attached to remanufactured ink jet cartridges which produced by manufacturers other than a particular manufacturer of ink jet chips, ink jet chips attached to remanufactured inkjet cartridges which are not functional, and inkjet chips attached to remanufactured inkjet cartridges which are not a particular type of new inkjet chips.
[0026] After the processing circuitry 200 completes the verification and rejection techniques described above, the processing circuitry 200 communicates with the user interface 204 to indicate the verification or rejection of the new ink jet to the user during the process of remanufacturing. For example, if the inkjet chip does not meet certain criteria, the user interface may indicate that status with a light or sound. Alternatively, the details of the type of inkjet chip may be displayed on a display of the user interface 204 .
[0027] Next, methods of verifying chips will be described. The methods will be described as being performed by the chip verifier. But, these methods can be performed by using any applicable equipment. Furthermore, the methods described are useful for any type of chip having a memory and are not limited to imaging chips or inkjet chips.
[0028] The chip verifier determines the chip type by performing a query on the chip presented to it. The return from the query identifies the printer type that the chip is presently pointing to. If the chip identified is possibly part of a universal chip, a multi-brand chip, or a multi-region chip, then the chip verifier starts to remarry the chip to see what other printer types (brands, or regions) it will answer to. The chip verifier can determine what chip type it is. The chip verifier will then re-marry the tag to the original printer data set that was found.
[0029] If the chip is determined to be a dedicated tag then the chip verifier tries to re-marry the chip to a predetermined chip. For example, the chip can by re-married to an chip whose data set should not be in the chip, but the data set is stored in one of the memory slots within the dedicated chips. If the marry is successful the chip is verified and gets reported as such. Otherwise, the chip does not get verified (i.e. it is an OEM chip or a competitor chip) the chip verifier reports “no use.”
[0030] When the chip verifier sees a data set (from an original read) it will also read other chip locations to verify that the data set is still virgin. If the data set is found to be non-virgin a “no use” is reported.
[0031] In one embodiment, the chip verification is performed by a sequence. A sync signal, a dummy word, and four values are sent to the chip. If the sequence is transmitted correctly, the chip responds by sending a sync command and four words of data. If the sequence is not transmitted correctly the chip does not respond. It is desirable to allow the chip verifier to test the chip without marrying it to a printer. Therefore, when the chip verifier Read command is successful, the UCAM lock bits do not increment when a Validation command is given (UCAM match successful). This mode is cleared when a CRC error is received or the chip is powered down.
[0032] For example, the chip verifier sends: a sync command (0x5695), a dummy word (bit 15 low), 0xE687, 0xD632, 0x2453, and 0x1FB7. A valid chip responds by sending a sync command and four words of data. The first word of data contains the reset count and configuration register data. The second through fourth words of data or identification data (ID 1 , ID 2 , ID 3 ). The ID 1 , ID 2 and ID 3 words are values that are set when the chip is programmed. They do not change and their only use is to inform the chip checker what tag was programmed. The programming software sets these values as: ID 1 μ000x, where x is first (MSN) nibble of serial number; ID 2 —yyyy, where yyyy is the lower 4 nibbles of serial number; and ID 3 —zzzz, where zzzz is the type code. The type code indicates which type of imaging device the chip is designed to operate in. Also, the type code indicates if the chip is a universal chip, a multi-brand chip, or a multi-region chip.
[0033] In another embodiment, chip check commands are used to verify the chip. The chip check commands are intended to be executed by an external device capable of driving the chip and executing the command protocols (for example the chip verifier). A chip check command can be executed at any time.
[0034] The chip check command is similar to a standard read or write command except the sync value. For example, the chip check command uses a sync value of 0x4e. The upper bits, which are normally unused in the command field are used to decode the chip check command. The command fields are defined as follows:
[0000]
TABLE 1
Sync
Command
Address
Data
CRC
Sync
Test
0x4e
0xa0
0x4
x
Y
0x1b
Read
Test
0x4e
0xa2
0x4
bits[31:0]
Y
0x1b
Write
Change
0x4e
0xd2
0x4
bits[47:32]
Y
0x1b
Type
bits[31:16]
View
0x4e
0xd0
bits[5:0]
x
Y
0x1b
Text
View
0x4e
0xf0
x
x
Y
0x1b
CSR
[0000]
TABLE 2
Sync
Command
Address
Data
CRC
Sync
Test
0x4e
0xa0
0x4
x
Y
0x1b
Read
Test
0x4e
0xa2
0x4
bits[31:0]
Y
0x1b
Write
Change
0x4e
0xd2
0x4
bits[31:24]
Y
0x1b
Type
bits[15:00]
View
0x4e
0xd0
bits[4:0]
x
Y
0x1b
Text
View
0x4e
0xf0
x
x
Y
0x1b
CSR
[0035] The read and write test commands are used to validate successful read and write sequences as well as testing internal data buses and memory control functions. The test write command transfers data to the memory test area while the test read command reads from this area.
[0036] The view text command accesses a four byte buffer that contains ASCII information about the selected chip type. These locations are accessed by bits 0:1 of the address field. Bits 5:2 of the address field select the text area. Note that bit 5 is inverted, ie, a value of 0x7 selects the last text field ( 15 ) while a value of 0xf selects text field 7 .
[0037] The view CSR command displays the CSR bits (47:40) in response bits [31:24] which indicates the selected chip type as well as other control information. It also displays CSR bits (39:16) in response bits [23:0].
[0038] The change type command writes bits [47:40] of the control and status register. This write occurs successfully if the transaction count is greater than 0. Only these eight bits are written by this command.
[0039] Such testing of the inkjet chip allows the remanufacturer to verify the operation of the inkjet chip without subjecting the remanufactured inkjet cartridge to some type of print testing. Print testing is generally not practical with inkjet chips as the inkjet chip would interpret the test as the first installation, causing the inkjet to store an incorrect installation date in chip memory and possibly limiting the warranty period.
[0040] The many features and advantages of the invention are apparent from the detailed specification. Thus, the appended claims are intended to cover all such features and advantages of the invention which fall within the true spirits and scope of the invention. Further, since numerous modifications and variations will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation illustrated and described. Accordingly, all appropriate modifications and equivalents may be included within the scope of the invention.
[0041] Although this invention has been illustrated by reference to specific embodiments, it will be apparent to those skilled in the art that various changes and modifications may be made which clearly fall within the scope of the invention. The invention is intended to be protected broadly within the spirit and scope of the appended claims. | Disclosed is a system and method for verifying a chip having a memory. Remanufacturers of imaging devices, such as inkjet printers or electrostatic printers, often have to use a replacement chip in order to reuse an imaging cartridge. It is desirable to have a system and method for determining if the replacement chip is suitable for use with a specific imaging cartridge. Also, it may be desirable to confirm that the chip was manufactured by a specific manufacturer. The disclosed system and method allow the remanufacturer a reliable and efficient way to verify chips. | 1 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application claims priority to U.S. Provisional Patent Application No. 61/613,327 filed Mar. 20, 2012, the content of which is incorporated herein by reference in its entirety.
FEDERALLY SPONSORED RESEARCH
This invention was made with government support under contract number W31P4Q-09-C-0028 awarded by the U.S. Army Contracting Command. The government has certain rights in the invention.
BACKGROUND
The present invention relates to heat transfer.
More specifically, the present invention relates to an apparatus and method for improving heat transfer from a heat source to a fluid flow. The rate of heat transfer from a heat transfer surface, such as a heat sink, to a fluid, such as air, is affected by flow conditions at the surface. Turbulent flow generally results in a higher heat transfer rate than laminar flow.
SUMMARY
In one embodiment, the invention provides a heat transfer apparatus. A surface exchanges heat from a heat source to a fluid. A first fluid driver drives a first portion of the fluid along the surface in a first direction. A second fluid driver drives a second portion of the fluid along the surface in a second direction. A third fluid driver drives a third portion of the fluid along the surface in a third direction. Each of the first direction, the second direction, and the third direction are substantially non-parallel to one another.
In another embodiment, the invention provides a heat transfer apparatus. A first wall of the apparatus has a first base portion, a first end portion, and a first surface extending between the first base portion and the first end portion. A second wall has a second base portion, a second end portion, and a second surface extending between the second base portion and the second end portion. The first surface and the second surface at least partially define a channel for heat exchange with a heat source. The heat source is thermally coupled to the first wall and the second wall, and a fluid. A first fluid driver drives a first portion of the fluid through the channel in a first direction. A second fluid driver drives a second portion of the fluid through the channel in a second direction. A third flow fluid driver driving a third portion of the fluid through the channel in a third direction. Each of the first direction, the second direction, and the third direction are substantially non-parallel.
In another embodiment, the invention provides a method for heat transfer from a surface to a fluid. The method includes directing a first fluid flow towards the surface in a first direction and directing a second fluid flow towards the surface in a second direction. The first and second fluid flows cooperate to cool the surface.
In another embodiment the invention provides a method for heat transfer from a surface to a fluid. The method includes driving a first portion of the fluid along the surface on a first axis that is substantially parallel to the surface. A second portion of the fluid is agitated with an agitator reciprocating on a second axis that is substantially non-parallel with the first axis. A third portion of the fluid is injected along a third axis that is substantially non-parallel with the first axis and second axis.
In another embodiment, the invention provides a heat transfer surface. A substrate has. A plurality of surface modification members are coupled to the surface. The surface modification members include a body structure projecting from the surface. The body structure has a base end and a distal end. The base end is coupled to the substrate and the distal end is wider than the base end.
In another embodiment, the invention provides a heat transfer surface. A substrate has a surface. An array of surface modification members are coupled to the surface. The surface modification members include a cylindrical body with a base end and a distal end. The base end is coupled to the substrate. A dome-shaped end-cap is coupled to the distal end.
In another embodiment, the invention provides a method of fabricating surface modification members on a substrate. The method includes depositing a titanium layer over the substrate and applying a photoresist over the titanium layer. The photoresist is selectively exposed to cure the selected portions of the photoresist. Uncured portions of the photoresist are removed. Portions of the titanium layer exposed when removing the uncured portions of the photoresist are removed, thereby exposing the substrate in a desired pattern. The exposed substrate is plated to form surface modification members. The remaining portions of photoresist and titanium are removed to exposed the surface modifications members.
Other aspects of the invention will become apparent by consideration of the detailed description and accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a heat transfer apparatus according to one aspect of the invention.
FIG. 2 is a perspective view of a heat transfer apparatus according to another aspect of the invention.
FIG. 3 is a perspective view of a heat sink of the heat transfer apparatus of FIG. 2 .
FIG. 4 is a perspective view of an agitator assembly of the heat transfer apparatus of FIG. 2 .
FIG. 5 is a perspective view of an agitator actuator of the heat transfer apparatus of FIG. 2 .
FIG. 6 is a side view of the agitator actuator of FIG. 5 .
FIG. 7 is a perspective view of a synthetic jet assembly of the heat transfer apparatus of FIG. 2 .
FIG. 8 is a cross-sectional view of a portion of the synthetic jet assembly of FIG. 7 .
FIG. 9 is a planar view of various nozzle configurations of a synthetic jet assembly.
FIG. 10 is a perspective view of a heat transfer apparatus according to another aspect of the invention.
FIG. 11 is a detailed cutaway view of a portion of FIG. 10 .
FIG. 12 is a perspective view of a dual heat transfer apparatus according to another aspect of the invention.
FIG. 13 is a perspective view of a heat transfer apparatus according to another aspect of the invention.
FIG. 14 is an exploded view of the heat transfer apparatus of FIG. 13 .
FIG. 15 is a cross-sectional view of a heat transfer apparatus according to another aspect of the invention.
FIG. 16 is a detailed view of a portion of FIG. 15 .
FIG. 17 is a cross-sectional view of a heat transfer apparatus according to another aspect of the invention.
FIG. 18 is a detailed perspective view of a portion of FIG. 3 .
FIG. 19 is a detailed view of a portion of FIG. 11 .
FIG. 20 is a perspective view of an array of surface modification members according to one aspect of the invention.
FIG. 21 is a perspective view of an array of surface modification members according to another aspect of the invention.
FIG. 22 illustrates a process for manufacturing surface modification members on a substrate.
DETAILED DESCRIPTION
Before any embodiments of the invention are explained in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the following drawings. The invention is capable of other embodiments and of being practiced or of being carried out in various ways.
In various embodiments, the invention includes methods and apparatus for improving heat transfer from a surface. The methods and apparatus include modifications of the surface as well as the use of multiple directions of fluid flaw in a cooperating manner to improve heat transfer. Without being limited as to theory, the methods and apparatus disclosed herein are believed to improve heat transfer by interfering with laminar flow at the surface, for example by inducing turbulent air flow.
FIG. 1 shows an embodiment of the invention in which multiple cooperating air flows are used to improve heat transfer from a surface. More specifically, FIG. 1 illustrates the combined, simultaneous operation of a first fluid driver (e.g., a bulk air mover such as a fan or blower), a second fluid driver (e.g., an agitator assembly), and a third fluid driver (e.g., a synthetic jet assembly) around a pair of heat transfer surfaces 12 defining a primary flow channel 16 . The first fluid driver causes a bulk airflow 20 to flow along (e.g. substantially parallel to) a primary flow axis 24 . The second fluid driver generates secondary flow 28 along a secondary flow axis 32 that is different from (e.g. substantially perpendicular to) the primary flow axis 24 . The third fluid driver generates tertiary airflow 36 along axes 40 that are different from (e.g. substantially perpendicular to) the primary flow axis 24 and the secondary flow axis 32 .
As stated above, it is believed that the secondary flow 28 and tertiary flow 36 over the heat transfer surfaces 12 increase heat transfer to the bulk airflow 20 along the primary flow axis 24 by substantially reducing laminar flow conditions along the heat transfer surfaces 12 . In various alternative embodiments, the first, second, and third axes may be at varying angles with respect to one another, for example in a range of 45-90 degrees apart, although the three axes do not have to all be at the same angle with respect to the others.
Referring to FIG. 2 , a heat transfer apparatus 44 is illustrated. The heat transfer apparatus 44 includes a heat sink assembly 48 , an agitator assembly 52 , synthetic jet assemblies 56 , and a blower 60 .
The heat sink assembly 48 includes a base wall 64 having an engagement surface 68 . The base wall 64 is oriented along a base plane 72 . The engagement surface 68 may be coupled to a heat source, such as a printed circuit board (PCB), a micro-processor, a flat-screen display, or other device that generates heat during operation.
Referring to FIG. 5 , opposite the engagement surface 68 , a plurality of fin walls 76 extend from the base wall 64 in cantilever fashion. Each fin wall 76 extends from a base end 80 , coupled to the base wall 64 , to a distal end 84 . Heat transfer surfaces 88 are defined between the base end 80 and the distal end 84 on two sides of each fin wall 76 . Each fin wall 76 further defines a first agitator cutout 90 , a second agitator cutout 92 , and a central cutout 96 disposed between the first agitator cutout 90 and the second agitator cutout 92 . The first agitator cutouts 90 of the fin walls 76 are substantially aligned, and define a first agitator channel 102 . The second agitator cutouts 92 of the fin walls 76 are substantially aligned, and define a second agitator channel 106 . The central cutouts 96 are substantially aligned, and collectively define central cavity 110 .
The central cavity 110 divides the fin walls 76 into two opposing groups 114 and 118 . Primary airflow channels 122 are defined between adjacent fin walls 76 of each group 114 and 118 , with opposing directions of airflow corresponding to the opposing groups. The primary airflow 122 channels terminate in the central cavity 110 . In some embodiments, a flow director may be disposed within the central cavity 110 for redirecting flow from the primary airflow channels 122 towards the blower assembly 60 ( FIG. 2 ).
Referring back to FIG. 2 , the blower assembly 60 draws bulk airflow 126 through the heat sink assembly 48 along the primary airflow channels 122 defined between the fin walls 76 . In the central cavity 110 ( FIG. 3 ), the bulk airflow is redirected along a blower axis 130 ( FIG. 2 ) that is substantially perpendicular to the primary airflow channels 122 . The blower assembly 60 may be an axial-type blower or a centrifugal-type blower or other mechanism for inducing bulk air flow. While the illustrated embodiments show the blower pulling bulk air flow 126 through the fin assembly, in some embodiments, hulk air flow may be pushed through the fins.
FIG. 4 illustrates the agitator assembly 52 . The agitator assembly 52 includes an agitator carrier 134 , an agitator actuator 138 , a first group of agitator members 142 , and a second group of agitator members 146 . The agitator carrier 134 includes a first carrier arm 150 and a second carrier arm 154 . Referring to FIG. 2 , the carrier arms 150 and 154 are spaced apart a distance 158 corresponding to a separation distance between the first agitator channel 102 and the second agitator channel 106 , respectively, such that the carrier arms 150 and 154 may reciprocate without interference from the fin walls 76 of the heat sink assembly 48 . Referring to FIG. 4 , the first and second carrier arms 150 and 154 are coupled to a connecting portion 162 . The connecting portion 162 is coupled to the agitator actuator 138 .
The first group of agitator members 142 is coupled to the first carrier arm 150 , and the agitator members 142 are spaced along the first carrier arm 150 to reciprocate between adjacent fin walls 76 of the heat sink 48 ( FIGS. 2 and 3 ). Referring to FIG. 4 , the second group of agitator members 146 is coupled to the second carrier arm 154 , and the agitator members 146 are spaced to reciprocate between adjacent fin walls 76 of the heat sink 48 ( FIGS. 2 and 3 ). Each agitator member 142 or 146 includes a substantially rectangular body 160 , although other shapes are also possible, for example square, curved, triangle, or other shapes that promote movement of gas (e.g. air). In some embodiments, the body 160 of the agitator member 142 or 146 is approximately the same size and shape as the fin walls 76 (e.g. FIG. 3 ) while in other embodiments the body 160 is smaller (e.g. FIG. 4 ). In the latter case, the body 160 may be placed at a location where air or other gas enters the space between adjacent fin walls 76 to disrupt laminar air flow as air enters the space, where the disrupted flow pattern continues downstream of the body 160 .
Referring to FIG. 5 , the agitator actuator 138 , includes a piezo stack 164 . The piezo stack 164 is disposed within an amplification body 166 . Referring to FIG. 6 , the amplification body 166 includes an oval loop shell 170 having a primary displacement axis 176 and an agitation axis 180 that is substantially perpendicular to the primary displacement axis. A support leg 184 and an actuation leg 188 are substantially aligned with the agitation axis 180 . The support leg 184 is fixedly coupled to a rigid support 192 . The rigid support 192 may be the heat sink assembly 48 ( FIG. 2 ), a surrounding cabinet, bulkhead, or other fixed structure. The actuation leg 188 is fixedly coupled to the connecting portion of the agitator carrier 150 ( FIG. 4 ).
Referring to FIG. 6 , expansion and contraction of the piezo stack 164 along the primary displacement axis 176 results in an amplified displacement along the agitation axis 180 . Reciprocating displacement of the agitator carrier 134 ( FIG. 4 ) along the agitation axis 180 results in the agitator members 142 , 146 reciprocating between their corresponding, adjacent fin walls 76 ( FIG. 2 ), generating secondary flow similar to that illustrated in FIG. 1 . Other means for moving the agitators could also be used, including, for example, a rotating cam driving a piston or a linear actuator.
Synthetic jets are generated by creating a closed chamber with a flexible diaphragm and one or a limited number of openings to act as a nozzle when the diaphragm is moved, moving air through the nozzle(s). Several different mechanisms can be used to move the flexible diaphragm, as described below. Referring to FIG. 7 , the synthetic jet assembly 56 includes a jet actuator 194 , a diaphragm 196 , and a jet body 198 . The jet actuator 194 includes a piezo stack 202 disposed within an amplification body 204 . The amplification body 204 includes an oval shell 206 having a primary displacement axis 210 and jet axis 214 that is substantially perpendicular to the primary displacement axis 210 . A support leg 218 and an actuation leg 222 are substantially aligned with the jet axis 214 . The support leg 218 is fixedly coupled to a rigid support, such as the blower assembly 60 ( FIG. 2 ), a surrounding cabinet, bulkhead, or other fixed structure. The actuation leg 222 is fixedly coupled to the flexible diaphragm 196 . Expansion and contraction of the piezo stack 202 along the primary displacement axis 210 results in an amplified displacement of the amplification body 204 along the jet axis 214 . Other means for driving the synthetic jet diaphragm 196 could also be used, including, for example, a rotating cam driving a piston or a linear actuator.
Referring to FIG. 8 , the jet body 198 includes a diaphragm surface 226 and a nozzle surface 230 . A cavity 234 is defined within the jet body 192 between the diaphragm surface 226 and the nozzle surface 230 . An array of nozzles 238 is defined by the nozzle surface 230 . Referring to FIG. 9 , in various embodiments the nozzles 238 can have an opening with one or more shapes including circular, square, plus- or star-shaped.
Referring to FIGS. 7 and 8 , when the amplification body 204 expands and contracts, the diaphragm 196 reciprocates along the jet axis 214 . Movement of the diaphragm 196 at the diaphragm surface 226 creates pressure transients with the cavity 234 , causing air or other fluids to be rapidly drawn into the cavity 234 and ejected from the cavity 234 through the nozzles 238 in a direction substantially parallel to the jet axis 214 . The nozzles 238 are spaced apart such that the airflow is discharged upon the distal ends 84 of the fin walls 76 ( FIG. 5 ), in a manner similar to the tertiary flow illustrated in FIG. 1 .
FIG. 10 illustrates a heat transfer apparatus 242 according to another embodiment of the invention. The heat transfer apparatus 242 includes a heatsink 246 with a base wall 250 and fin walls 254 extending from the base wall 250 . The base wall 250 is coupled to a heat spreader 258 . A microchip 262 is sandwiched between a chip carrier 266 and the heat spreader 258 .
Agitator plates 270 are disposed between the fin walls 254 . The agitator plates 270 are coupled to an agitator carrier 274 . The agitator carrier 274 is coupled to an agitator actuator 278 including a piezo stack 282 . Referring to FIG. 11 , a synthetic jet assembly 286 includes a jet body 290 and a diaphragm 294 . The jet body 290 includes a diaphragm surface 298 and a nozzle surface 302 . An array of cavities 306 are defined within the jet body 290 between the diaphragm surface 298 and the nozzle surface 302 , with a corresponding array of nozzles 310 (one per cavity 306 ) defined by the nozzle surface 302 . The diaphragm 294 includes an array of piezo bender actuators 314 , with one piezo bender actuator 314 substantially aligned with each cavity 306 . When the piezo bender actuators 314 expand and contract, the diaphragm 294 reciprocates over cavities 306 . This diaphragm movement creates pressure transients with the cavities 306 , causing air or other fluids to be rapidly drawn into the cavity 306 and ejected from the cavity 306 upon the fin walls 254 .
FIG. 12 illustrates a dual heat transfer apparatus 318 according to another aspect of the invention. The dual heat transfer apparatus 318 includes a first heat sink 322 and a second heat sink 326 , a first agitator assembly 330 and a second agitator assembly 334 , a first synthetic jet assembly 338 and a second jet assembly 342 , and a first blower 346 and a second blower 350 . Each of the first and second synthetic jet assemblies 338 and 342 includes a diaphragm 354 oriented substantially perpendicular to a synthetic jet body 358 . Manifolds 362 fluidly connect each diaphragm 354 to its corresponding synthetic jet body 358 .
FIGS. 13-14 illustrate a heat transfer apparatus 366 according to another aspect of the invention in which the heat transfer surface (e.g. one or more fins) is an outer wall of a heat pipe. The heat transfer apparatus 366 includes a blower assembly 370 , an agitator and synthetic-jet assembly 374 , and a heat pipe heat sink 378 . The heat pipe 378 includes a base portion 382 and rib portions 386 (e.g. fins) extending from the base portion 382 . The base portion 382 and rib portions 386 define a vapor chamber 390 .
A heat pipe vapor chamber is a heat-transfer device that combines the principles of both thermal conductivity and phase transition. A liquid within the vapor chamber turns into a vapor by absorbing heat from a first surface (e.g. at the base portion). The vapor condenses back into a liquid at a cold surface (e.g., at the ribs), releasing the latent heat. The liquid then returns to the hot interface through capillary action where it evaporates once more and repeats the cycle. In addition, the internal pressure of the heat pipe can be set or adjusted to facilitate the phase change depending on the demands of the working conditions of the thermally managed system.
FIGS. 15-16 illustrates a heat transfer apparatus 394 according to another aspect of the invention. The heat transfer apparatus 394 includes a heat pipe 398 with a vapor chamber 402 , similar to that described with respect to the heat transfer apparatus of FIG. 13 . The heat transfer apparatus 394 includes a synthetic jet assembly 406 including piezo agitators 410 . The piezo agitators 410 extend from a synthetic jet body 414 , between adjacent nozzles 418 of the synthetic jet body 414 .
FIG. 17 illustrates a heat transfer apparatus 422 according to yet another aspect of the invention. The heat transfer apparatus 422 includes a heat sink 426 with a base portion 430 and fin walls 434 extending from the base portion 430 . The fin walls 434 have an inlet end 438 and an outlet end 442 , with flow channels 446 defined between the fin walls 434 from the inlet end 438 to the outlet end 442 . A blower assembly 450 includes a blower housing 454 and a centrifugal blower 458 . The blower housing 454 includes a blower inlet 462 that receives air from the fin wall outlet end 442 . When in operation, the centrifugal blower 458 draws air or other fluids through the flow channels 446 of the heat sink 426 , from the inlet end 438 to the outlet end 442 . The air is then redirected through the blower inlet 462 and into the centrifugal blower 458 .
Referring to FIGS. 18 and 19 , the heat transfer surfaces in some embodiments (e.g., FIG. 3 ) include an array of surface modification members 466 or pin fins. As discussed above, the surface modification members 466 are believed to disrupt or substantially reduce laminar flow across the heat transfer surface and are sized and shaped for optimal use with gases (in particular air) as the fluid for heat removal.
FIGS. 20 and 21 illustrate two embodiments of the surface modification members. FIG. 19 illustrates the surface modification members in a cylindrical pin fin configuration 470 . Although cylindrical (i.e. having a circular cross-section) pin fins 470 are illustrated, the pin fins 470 can have a variety of shapes, for example having cross-sections that are oval, triangular, square, or other regular or irregular polygon or curved shapes. The cylindrical pin fins 470 include a cylindrical body 474 with a base end 478 and a distal end 482 . The base end 478 is coupled to the heat transfer surface 88 (the substrate). The cylindrical pin tins have a height from the substrate of H 1 and diameter of the cylindrical body D 1 . In one embodiment, the diameter D 1 is approximately 500 micrometers, with a height H 1 of approximately 250 micrometers. In another embodiment, the diameter D 1 is approximately 75 micrometers, with a height H 1 of 150 micrometers.
The spacing of the pin fins can influence the heat removal performance of the surface to which the pin fins are attached. The cylindrical pin fins 470 are separated from each other by a distance S 1 . A ratio of the separation distance S 1 to the diameter D 1 (i.e., S 1 :D 1 ) is approximately 6:1.
FIG. 21 illustrates the surface modification members in which the pin fins have an overall shape resembling a mushroom. The mushroom-shaped pin fins 486 include a cylindrical body 490 with a base end 494 and a distal end with a dome-shaped end-cap 498 . The base end 494 is coupled to the heat transfer surface 88 (the substrate). Although the end-caps 498 are shown as being dome-shaped, other end-cap shapes are possible including a pin fin with an overall tapered shape, with the general property that the distal ends of the pin fins have a larger width than the width of the base. The end-cap 498 has a height H 2 from the substrate and a maximum diameter (at the end cap) D 2 and a base diameter (at the base end) of D 3 . In one embodiment, the diameter D 2 is approximately 500 micrometers, the diameter D 3 is approximately 50-65 micrometers, with a height H 2 of approximately 250 micrometers. In another embodiment, the diameter D 2 is approximately 75 micrometers, the diameter D 3 is approximately 50-65 micrometers, with a height of 150 micrometers. A ratio of the separation distance S 2 to the diameter D 2 (i.e., S 2 :D 2 ) is approximately 6:1.
FIG. 22 illustrates a method of fabricating surface modification members 466 on a first surface and a second surface of a copper substrate 506 (e.g., a copper fin wall). First, a titanium (Ti) layer 510 is deposited over the fin wall 506 . Next, a high contrast, epoxy based photo resist 514 (e.g., KMPR®) is applied over the Ti layer 510 . The photo resist 514 is selectively cured to establish a mold pattern 518 , and the unexposed photo resist 514 is washed away. After removal of the unexposed photo resist 514 , the Ti layer 514 is washed away from mold areas 522 , selectively exposing the copper substrate 506 in the mold pattern. Copper plating 526 is then applied to the exposed copper substrate 506 , thereby forming the surface modification members 466 . Finally, the remaining cured photo resist 514 and titanium 510 is washed away, leaving only the copper substrate 506 and surface modifications 466 .
Thus, the invention provides, among other things, a heat transfer apparatus. Various features and advantages of the invention are set forth in the following claims. | A method is provided for heat transfer from a surface to a fluid. The method includes directing a first fluid flow towards the surface in a first direction and directing a second fluid flow towards the surface in a second direction. The first and second fluid flows cooperate to cool the surface. | 5 |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.