description stringlengths 2.98k 3.35M | abstract stringlengths 94 10.6k | cpc int64 0 8 |
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BACKGROUND OF INVENTION
[0001] 1. Field of Invention
[0002] The field of invention relates generally to toilet design, toilet accessories, and in particular the invention relates to liftable toilet seat design.
[0003] 2. Description of Prior Art
[0004] Since the invention of the modem toilet, there have been improvements to its design and function. While this field of invention is not considered glamorous, it is an essential component of our society's sanitary handling of bodily waste. The invention of the liftable toilet seat was a noted improvement of the design, allowing for more sanitary use of the toilet from both standing and sitting positions. However, in order to lift the common toilet seat, one has to use their hands to do so. From an ease of use standpoint and from a sanitary standpoint, it is the goal of the foot liftable toilet seat to improve upon the standard toilet seat.
[0005] Toilet Seat Lifting devices have been patented since the 1970's [R35] and there have been numerous designs. Most of these designs have failed to gain wide spread acceptance and use. In order to understand why, one must first look at the designs to see what design flaws might have contributed to this. The patents listed in the references fall into one of three catagories:
Attachable handle designs. [R1, R4, R5, R6, R9, R13, R24, R25, R34, R35] Mechanical lift designs. [R2, R3, R7, R10, R11, R12, R14, R16, R19, R20, R21, R23, R26, R27, R28, R29, R30, R31, R32, R33] Handicap assist lift designs. [R8, R15, R17, R18, R22]
[0009] The last of the three, handicap assist lift designs, are typically larger and more mechanically complex. This is in part due to the design requirement that they assist the individual from the sitting to the standing position, thus the need to perform load bearing operations. The handicap assist lift designs perform an important function in society, but this function is considered a niche market in the toilet industry and is not the intended sector of the Foot Liftable Toilet Seat. Thus, this type of design will not further be discussed.
[0010] Mechanical lift designs come in a variety of types ranging from purely mechanical advantage lever based designs to much more complicated mechanical hydraulic, mechanical pneumatic, or mechanical electric designs. Most of these designs are intended to be aftermarket devices that are fitted onto or around an existing standard toilet. These mechanical lift designs have two primary inhibitors to wide spread acceptance. First, they have a fairly complex design, which leads to cost concerns. Second, the same mechanical complexity often involves a large number of exposed parts which is more difficult to keep clean.
[0011] Attachable handle designs are typically simple in devices that are attached to the underside of an existing toilet seat, either through the use of adhesives or screws. Various designs exist ranging from simple knobs, to custom handles such as miniature baseball bats. While acceptable for household use, these designs lack the ruggedness that is required for widespread acceptance in public restrooms. They are too prone to breakage and vandalism for public restroom use, which is one of the primary markets that the Foot Liftable Toilet Seat is intending to pursue. In addition, some of the designs are also more difficult to clean than the Foot Liftable Toilet Seat.
BRIEF SUMMARY OF THE INVENTION
[0012] The invention consists of a standard toilet seat whose shape has been modified to include one or more foot liftable protrusions that extend past the side or front of the toilet bowl. It provides hands free raising and lowering of the seat via one's foot, thereby allowing for more sanitary use of the toilet. A foot liftable protrusion is defined as a feature of the toilet seat (either integral or added on) that extends past the toilet bowl and allows the user to raise and lower the toilet seat with their foot. These foot liftable protrusions can be located anywhere along the toilet seat (from back to front). This foot liftable toilet seat can be attached to any standard toilet.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] The following is a brief description of the drawings enclosed in this document. For a complete understanding of the content of these drawings and the objects of the invention, please refer to the detailed description of the invention in this document.
[0014] The accompanying drawings are:
Example Foot Liftable Toilet Seat Schematic Drawings
[0015] FIG. 1 . is a top view schematic of an example design for a closed front foot liftable toilet seat.
[0016] FIG. 2 . is a top view schematic of an example design for an open front foot liftable toilet seat.
Example Closed Front Foot Liftable Toilet Seat 3D Sketches
[0017] FIG. 3 . is a top view rendering of an example design for a closed front foot liftable toilet seat.
[0018] FIG. 4 . is a right view rendering of an example design for a closed front foot liftable toilet seat.
[0019] FIG. 5 . is a front view rendering of an example design for a closed front foot liftable toilet seat.
[0020] FIG. 6 . is an isometric view rendering of an example design for a closed front foot liftable toilet seat.
Example Open Front Foot Liftable Toilet Seat 3D Sketches
[0021] FIG. 7 . is a top view rendering of an example design for an open front foot liftable toilet seat.
[0022] FIG. 8 . is a right view rendering of an example design for an open front foot liftable toilet seat.
[0023] FIG. 9 . is a front view rendering of an example design for an open front foot liftable toilet seat.
[0024] FIG. 10 . is an isometric view rendering of an example design for an open front foot liftable toilet seat.
DETAILED DESCRIPTION OF THE INVENTION
[0025] The invention, the foot liftable toilet seat, aims to address various sanitary and usage concerns that standard toilet seats have. First, the standard toilet seat in some situations (for example in public restrooms) often experiences the scenario where the user was either too lazy to lift the seat or was unwilling to lift the seat with their hands. What typically happens is that the toilet seat is left down and urine gets on the seat. Toilet seat paper sanitary barriers attempt to address this problem. However, the sanitary barrier dispensers are often empty. What is preferable is to offer the user a simple way of lifting the seat with their foot, thus avoiding any direct skin contact with the toilet seat. In addition, the foot liftable toilet seat is more ergonomic because it doesn't require the user to bend over to pick it up. [R36, R37]
[0026] The two example designs shown in FIG. 1 and FIG. 2 illustrate both closed and open front foot liftable toilet seat designs. The toilet bowl (C 02 ) and reservoir basin (C 01 ) are standard toilet designs found in home settings. It should be noted that the foot liftable toilet seat is able to be installed on or adapted to use on any toilet, residential or commercial. The foot liftable toilet seat is mountable via the standardized mounting brackets for toilet seats (C 05 ).
[0027] The closed front foot liftable toilet seat (C 03 ) is an example design that would more typically be found in (but not limited to) residential settings. It consists of a standard liftable toilet seat whose shape has been modified to include one or more foot liftable protrusions (C 04 ) that extend past the side of the toilet bowl (C 02 ). A foot liftable protrusion is defined as a feature of the toilet seat (either integral or added on) that extends past the toilet bowl and allows the user to raise and lower the toilet seat with their foot. These foot liftable protrusions can be located anywhere along the contour of the toilet seat (from back to front). The example design shows the foot liftable protrusions (C 04 ) at the front of the liftable toilet seat (C 03 ) to minimize required lifting force.
[0028] The open front foot liftable toilet seat (C 06 ) is an example design that would more typically be found in (but not limited to) public restroom settings. It consist of a standard open front liftable toilet seat whose shape has been modified to include one or more foot liftable protrusions (C 07 ) that extend past the side of the toilet bowl (C 02 ). The open front design has a primary difference from the closed front design in that its front is discontinuous (C 08 ). This opening provides favorable sanitary and cleaning conditions particular to male public bathrooms. Often in male public restrooms, the toilet stalls are used as capacity overflow urinals and the ability to easily lift or lower the toilet seat with one's foot would be advantageous.
[0029] The operation of the foot liftable toilet seat is simple and ergonomic. The user simply places their foot beneath the foot lift protrusion (C 04 & C 07 ), also known as the foot lift tab, and lifts the toilet seat up. Conversely, to lower the toilet seat, the user extends their leg and hooks their foot under the foot lift tab and then pulls their leg back and gently lowers the seat to the sitting position.
[0030] While the invention has been described with reference to an example embodiment, it will be understood by those skilled in the art that a variety of modifications, additions, and deletions are within the scope of the invention as defined by the following claims. | A toilet seat that is easily liftable and lowerable with the user's foot is described. This foot liftable toilet seat can be attached to any standard toilet. It provides hands free raising and lowering of the seat allowing for more sanitary use of the toilet. | 0 |
FIELD OF THE INVENTION
This invention relates to hydraulic expansion tubes which may be used in mining, construction and excavation.
BACKGROUND OF THE INVENTION
In mining, construction and excavation operations it is often necessary to break apart large portions of solid rock. Traditionally, surface pieces of rock could be broken away using rock chisels and/or hammers. In order to break apart larger portions of rock a wedge may be used to split the rock apart. However, these methods are both labour intensive and time consuming.
Since the advent of explosives, dynamite has often been used to break apart larger portions of rock. Typically, the dynamite is inserted into a bore hole that is drilled into the rock. When the dynamite explodes the pressure generated by the explosion or blast inside the bore hole splits the rock apart. Such explosions may be used alone or in conjunction with each other to break apart large portions of rock in a short period of time.
However, the explosive nature of dynamite makes it very dangerous to work with. Extensive safety precautions must be employed in the storage, transportation and use of dynamite. Additionally, when dynamite explodes it destroys itself, the detonating caps and much of the detonating wire. Accordingly, these components are non-reusable and must be replaced with each new use. Furthermore, the explosion of dynamite creates a shockwave that is both loud and potentially damaging to sensitive structures. As such, dynamite blasting is often prohibited in urban areas.
SUMMARY OF INVENTION
In accordance with an aspect of the present invention there is provided an expander, comprising a support shaft, a pair of sleeves received on the support shaft proximate either end of the support shaft, an expandable tube disposed about the support shaft and the sleeves, a pair of end caps proximate either end of the support shaft surrounding the expandable tube such that proximate each end of the support shaft an end cap and a sleeve sandwich said expandable tube so as to make an interference fit with the expandable tube, and a port for porting hydraulic fluid between said support shaft and said expandable tube.
In accordance with another aspect of the present invention there is provided an expander an described above further comprising an expandable sheath disposed about said expandable tube at each said end cap for minimizing expansion of said expandable tube over said end cap.
The present invention may be inserted into a bore hole to split apart rock. An advantage of the present invention is that is it quiet, reusable and does not generate an explosive shock wave. The absence of an explosion makes the present invention safer to use and better suited for use in urban areas.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention will be further understood from the following detailed description, with reference to the drawings in which:
FIG. 1 illustrates in cross-section a side view of an unexpanded expander in accordance with an embodiment of the present invention.
FIG. 2 illustrates in cross-section an enlarged side view of the left hand end of the unexpanded expander shown in FIG. 1 .
FIG. 3 illustrates an exploded view of the expander in FIG. 1 absent the sheathes and with a portion of the expandable tube cut away to expose the support shaft inserted there through.
FIG. 4 illustrates in cross-section an enlarged side view of the support shaft shown in FIG. 1 .
FIG. 5 illustrates in cross-section a side view of an expander of FIG. 1 when expanded and confined by a bore hole.
FIG. 6 illustrates in cross-section a side view of an unexpanded expander in accordance with a second embodiment of the present invention.
FIG. 7 illustrates in cross-section a side view of the expander of FIG. 6 when expanded and not confined by a bore hole.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referencing FIGS. 1 to 4 , an expander 10 comprises a support shaft 12 with a pair of sleeves 14 a , 14 b received thereon proximate either end 15 a , 15 b of the shaft. An expandable tube 16 is disposed about the support shaft and the sleeves 14 a , 14 b . The tube is preferably elastic, being preferably formed of rubber, and most preferably nitrile rubber. A pair of sheathes 18 a , 18 b near each end of the support shaft 12 surround the rubber tube and a pair of end caps 20 a , 20 b proximate each end of the shaft surround the rubber tube and a portion of the sheathes 18 a , 18 b . The sheathes have some elasticity, but are preferably less elastic than the rubber tube. The sheathes may be made of nylon. The ends of the support shaft are threaded and receive end nuts 24 a , 24 b . Nut 24 a has a tab 26 with an opening 28 therein.
The support shaft has an hydraulic port 30 through end 15 a which connects with an input conduit 32 a that ends in radial stub conduits 34 a which open to the outside of the shaft. The end 15 b of the shaft 12 has a bleed port 38 connected to a bleed conduit 32 b which ends in radial stub conduits 34 b which open to the outside of the shaft. A bleed end cap 40 seals the bleed port 38 . A series of O-rings 42 provide seals against hydraulic fluid leakage.
As best seen in FIG. 2, a portion 46 of the exterior of each sleeve 14 is threaded and a portion 48 of the interior of each end cap 20 is also threaded. The sleeve and end cap are configured so that these threaded portions mate so that the sleeve may be threaded to the end cap. A further portion 50 of the end cap 20 is threaded with a thread opposite in orientation to that of the threaded portion 46 of the sleeve, and it will be noted that each end of the rubber tube is sandwiched between an end cap and sleeve at their threaded portions 46 , 50 , respectively, in order that the grip on the tube by the end cap and sleeve combination is enhanced.
The end cap 20 terminates in an apical unthreaded lip portion 52 with a rounded edge 53 under which the sheath 18 extends. The outside surface of the end cap 20 tapers from a wide apex 54 at lip portion 52 to a narrow base 56 . The end cap also has a shoulder 58 .
The sleeve 14 has a basal flange 60 which abuts against shoulder 58 of the end cap and an apical interior radially stepped portion 62 . The sleeve 14 is spaced from the shaft 12 along portion 62 and portion 62 extends over the radial stub conduits 34 of the shaft. The sleeve 14 also has a shoulder 68 which abuts a corresponding shoulder 70 of shaft 12 .
Turning to FIG. 5, in operation, expander 10 may be inserted in a bore hole through rock. Pressurised hydraulic fluid is then injected into the expander through port 30 . The fluid squirts through conduit 32 a and stub conduits 34 a exiting the support shaft 12 at portion 62 of sleeve 14 a . Portion 62 of the sleeve redirects the fluid flow so that the pressurised fluid does not squirt directly onto the rubber tube 16 (which could damage the tube). The fluid fills the annular space 66 between the support shaft and the rubber tube and the fluid pressure forces the medial section of the rubber tube between the end caps 20 a , 20 b to expand against the sides of the borehole. It has been found that pressures of 2,000 to 10,000 psi are typically required to fracture the rock through which such a borehole extends. Once the rock fractures, the pressure quickly drops as the rubber tube is freed to expand; this pressure drop may be used as a feedback signal to cut off the hydraulic fluid supply. It is also contemplated that several expanders 10 may be connected in series (by coupling the bleed port 38 of one expander to the hydraulic port of the next through a suitable coupling) to extend the operational length.
While the rubber tube 20 expands, each sheath 18 a , 18 b acts to minimize expansion of the expandable tube 16 over the outside surface of the end cap 20 a , 20 b with which it is associated. This greatly reduces fatigue of the rubber and therefore prolongs the life of the rubber tube 16 .
After the rock has been fractured and the hydraulic fluid cut off, the expander 10 may be removed from the borehole by a suitable hook received through opening 28 in tab 26 .
When expander 10 is first hooked up to an hydraulic supply, the expander will contain air rather than hydraulic fluid. Pressurising this air to the working pressures of the expander could result in dangerous failure. Consequently, after first hooking the expander to an hydraulic supply, bleed end cap 40 is removed and low pressure fluid is introduced into the expander. This forces the air out of the expander through bleed conduit 32 b . Once fluid begins to emerge from bleed port 38 , the bleed end cap 40 may be reinserted to close bleed port 38 .
The size of the bore hole is such that the wide apex 54 of the end caps makes a close tolerance fit with the sides of the bore hole. This further assists in ensuring that the rubber of the tube does not expand around the outside of the end caps. Lip 52 is provided with a rounded edge 53 to prevent sheaths 18 and expandable tube 16 from being pinched and damaged during expansion. The end caps are tapered from their wide apices to ease manipulation of the expander in the borehole.
The interference fit that the threaded end cap and sleeve portions make with the ends of the rubber tube provides a strong bite on the rubber tube which minimized its creep away from the base 56 of the end caps with repeated use.
The expander may be assembled as follows. First the end caps 20 a , 20 b are turned while they are pressed against the ends of the rubber tube so that they “screw” onto the tube. Next the support shaft is inserted through the rubber tube. After this, each sleeve 14 a , 14 b is screwed into its end cap 20 a , 20 b until the shoulder 68 of the sleeve abuts the shoulder 70 of the shaft 12 . This pinches the rubber tube between the sleeves and end caps. Lastly the end nuts 24 a , 24 b are threaded to the threaded ends 15 a , 15 b of the shaft 12 . When it is necessary to replace a fatigued rubber tube 16 , this process is reversed.
Optionally, the bleed end cap 40 may be replaced by a spring loaded valve which may be opened by a user applying external pressure. Optionally, instead of tapering the end caps, they may simply have an enlarged apical lip.
The nylon sheathes have the disadvantage that they may slowly break down in a caustic environment. Optionally, therefore, the nylon sheathes may be replaced with a coil spring or by a flat steel spring. Further, the sheathes may optionally not be overlapped by the end caps but, instead, terminate at the apical edge of the end caps. This option is not preferred, however, as sheathes so positioned provide less protection against the rubber tube expanding over the outside of the end caps.
A simplified embodiment of an expander made in accordance with this invention is illustrated in FIG. 6 . Turning to FIG. 6, wherein like parts have been given like reference numerals, expander 100 has sleeves 114 a , 114 b which are not threaded. Each sleeve abuts basal portion 156 of an end cap 120 a , 120 b . The end caps 120 a , 120 b are also not threaded. And no sheathes are employed in expander 100 . Expander 100 is assembled by placing sleeves 114 a , 114 b over the end portions of the support shaft 12 until the shoulders 68 of the sleeves abut the shoulders 70 of the shaft 12 , pushing the rubber tube 16 onto the shaft 12 then forcing on the end caps 120 a , 120 b . In forcing an end cap overt the rubber tube, air will become trapped between the end of the rubber tube and the basal portion 156 of the end cap. To avoid this potential problem, preferably a bleed conduit (not shown) is provided through the base of the end cap to allow this air to escape. After the end caps are in place, the end nuts 24 a , 24 b may be threaded to the assembly.
Referencing FIG. 7, after assembly, hydraulic fluid may then be injected into port 30 . The fluid will squirt through stub conduits 34 a and be redirected by apical portion 162 of sleeve 114 a . The fluid in annular space 66 will then cause the rubber tube 16 to expand. The tight interference fit between the sleeves 114 a , 114 b and the end caps 120 a , 120 b minimizes creep of the tube away from the basal portions 156 of the end caps.
Other modifications will be apparent to those skilled in the art. | An hydraulic expansion tube is provided which may be inserted into bore holes and expanded to break apart rock. An expandable tube is secured at its ends with end caps and sleeves which are carried on a support shaft. The end caps and sleeves form a tight interference fit with the ends of the expandable tube. Hydraulic fluid is ported through the support shaft into the interior of the expandable tube. The end caps and sleeves may be provided with threads to better grip the expandable tube and prevent it from pulling away from the end caps after repeated expansion. Additionally, an expandable sheath may be provided to surround the ends of the expandable tube to limit the expandable tube from flowing around the end caps when pressurized. | 4 |
CROSS REFERENCE TO RELATED APPLICATION
This application is a continuation-in-part of U.S. patent application Ser. No. 11/052,261 filed Feb. 7, 2005, now U.S. Pat. No. 7,102,451, claiming priority to U.S. Provisional Application No. 60/545,359, filed on Feb. 18, 2004, and this application claims priority to U.S. Provisional Application No. 60/630,024, filed on Nov. 22, 2004, the disclosure of each application is hereby incorporated by reference in its entirety.
STATEMENT OF GOVERNMENT FUNDED RESEARCH
This work was supported by the Air Force Office Scientific Research FA9550-04-1-0199. Accordingly, the Government has certain rights in this invention.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to the field of optically pumped atomic clocks, optically pumped atomic magnetometers, pulse laser systems, and more particularly to a laser that is self-modulated by alkali-metal vapor at 0-0 atomic-clock frequency by using light of alternating polarization referred to as push-pull optical pumping technique.
2. Description of the Related Art
Gas-cell atomic clocks and magnetometers use optically pumped alkali-metal vapors. Atomic clocks are applied in various systems that require extremely accurate frequency measurements. Atomic magnetometers are utilized in magnetic field detection with extremely high sensitivity. For example, atomic clocks are used in GPS (global positioning system) satellites and other navigation systems, as well as in high-speed digital communication systems, scientific experiments, and military applications. Magnetometers are used in medical systems, scientific experiments, industry and military applications.
A vapor cell used in atomic clocks or magnetometers contains a few droplets of alkali metal, such as potassium, rubidium, or cesium. A buffer gas, such as nitrogen, other noble gases, or a mixture thereof, is required to be filled inside the cell to match the spectral profile of the pumping light, suppress the radiation trapping, and diminish alkali-metal atoms diffusing to the cell wall. The gas cell is heated up to above room temperature to produce sufficient alkali-metal vapor. The resonances of alkali-metal ground-state hyperfine sublevels are especially useful for atomic clocks and atomic magnetometers. The hyperfine resonance is excited by rf (radio frequency) fields, microwave fields, or modulated light (CPT: coherent population trapping method). The resonance is probed by the laser beam. As shown in FIG. 1 , hyperfine 0-0 resonance, ν 00 , is particularly interesting for atomic clocks because of its insensitivity of the magnetic field at low field regime; hyperfine end resonance, ν end , can be used either for atomic clocks and magnetometers; the Zeeman end resonance, ν z , is usually used for a magnetometer because of its high sensitivity of the magnetic field. Besides the three illustrative resonances, other resonances of different hyperfine sublevels can also be used for atomic clocks and magnetometers. The resonance signal is reflected on the probing beam as a transmission dip or a transmission peak when the frequency is scanned through the resonance frequency. Conventionally, an atomic clock or a magnetometer measures the frequency at the maximum response of the atomic resonance. A local oscillator is required to generate the oscillation signal and excite the resonance. For a passive-type atomic clock, the frequency of the local oscillator is locked to the peak resonance as shown in FIG. 2 . A precise clock ticking signal is therefore provided by the output of the local oscillator.
The development of atomic clocks and magnetometers is heading in the direction of low power consumption and compact size. To reduce the size and the complexity of the atomic clocks, the CPT method has been introduced for the atomic clock to get rid of microwave cavity. The conventional CPT method with fixed circularly polarized light and FM modulation suffers from the effects of population dilution and high buffer-gas pressure. Accordingly, it has a very small resonance signal. As for the power consumption of a conventional passive atomic clock, the local oscillator and the microwave circuitry can be a major draining source because of the complexity of the microwave circuitry and feedback loops of the passive-type atomic clocks. For a portable atomic-clock device, relatively high power consumption can reduce the battery lifetime and therefore decrease the utility of the miniature atomic clock.
It is desirable to provide an improved method and system for reducing complexity and power consumption of an atomic clock or magnetometer.
SUMMARY OF THE INVENTION
The problem of conventional CPT has been solved by Push-Pull pumping technique. Push-pull pumping can boost up the CPT signal by a significant factor and therefore effectively improve the performance of CPT atomic clocks. The present invention provides a method and apparatus for operating atomic clocks or magnetometers without a local oscillator and without an electronic feed-back loop for stabilizing the local-oscillator frequency. The atomic-clock signal is directly obtained from self-modulated laser light. The method and system is based on the physics of a push-pull optical pumping technique using an alkali-metal vapor cell placed inside a laser cavity to modulate the laser light at the frequency of the hyperfine resonance. In the laser cavity, a photonic gain medium, such as laser diodes or other kinds, can amplify the photon flux at different optical frequencies. Depending on the cavity configuration, optics may be needed to control the light polarization and the optical bandwidth. A fast photodetector can convert the modulated light into the clock ticking signal in electrical form with some optics.
A laser is a positive feedback amplifier of photons. An alkali-vapor cell inside the laser cavity operates similar to a photonic filter and converter to generate a special lasing mode, which produces the light modulation. Generally, a laser tends to lase in an optical mode, which has the maximum gain or the minimum loss of photons from their round-trip inside the cavity. Without the vapor cell, the lasing spectrum is determined by the characteristics of the laser cavity and the gain profile. With a vapor cell inside the cavity, a steady lasing point is met while the lasing spectrum produces the maximum efficiency of push-pull optical pumping, which makes the vapor cell become the most transparent. At this point, the output laser light is modulated at hyperfine frequency. If a 0-0 hyperfine resonance is chosen for light modulation, the output laser light serves as an atomic-clock signal. If other magnetic field dependent resonances for light modulation are chosen, the output laser light serves as a magnetometer signal.
Preferably, push-pull optical pumping can be used with D 1 light of alkali-metal atoms, since D 1 pumping light has better efficiency for CPT excitation of ground-state hyperfine coherence of alkali-metal atoms. Push-pull pumping tends to excite the electron spin oscillation at the hyperfine frequency. The oscillation of the electron spin of the alkali-metal vapor can modulate the light intensity. In a closed-loop laser cavity, the light modulation from the vapor can be amplified by the gain medium, and it generates a steady push-pull pumping light. The initial excitation of spin oscillation can be produced by the laser noise, laser instability, and the like. Spontaneous push-pull pumping is generated if the round-trip gain of the push-pull pumping light is greater than one, thereby providing a self-modulated laser system.
The invention will be more fully described by reference to the following drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic diagram of the ground-state hyperfine energy levels of a representative alkali-metal atom with nuclear spin I=3/2.
FIG. 2 is a schematic diagram of a prior art passive, gas-cell, atomic clock system.
FIG. 3 is a flow diagram of a method for operating an atomic clock or magnetometer using a push-pull pumping technique.
FIG. 4 is a flow diagram of a method for operating a self-modulated laser in accordance with the teachings of the present invention.
FIGS. 5A-5C are illustrative diagrams of hyperfine coherence as electron spin oscillation, the format of the push-pull pumping light at time domain, and the light absorption of the atomic vapor modulated by the spin oscillation.
FIG. 6 is an illustrative diagram of the spectrum of push-pull pumping light inside the vapor cell and the spectral response of the entire laser system.
FIGS. 7A-7D are schematic diagrams of embodiments of cavity configurations for a laser modulated at hyperfine frequency.
FIG. 8 is a plot of simulation result of a diode-laser not modulated by the 87 Rb cell using the configuration of FIG. 7A when the gas cell has insufficient vapor density.
FIG. 9 is a plot of the simulation result of a diode-laser modulated by the 87 Rb cell using the configuration of FIG. 7A when the gas cell has sufficient vapor density.
FIG. 10 is a plot of the simulation result of a diode-laser modulated by the 133 CS cell using the configuration of FIG. 7A when the gas cell has sufficient vapor density.
FIG. 11 is an illustrative animation of the laser intensity and electron spin of alkali-metal atoms when the laser is steadily modulated by the vapor cell.
FIG. 12 is a plot of the simulation result of a polarization-diverse laser diode modulated by the 85 Rb cell using the configuration of FIG. 7D .
DETAILED DESCRIPTION
Reference will now be made in greater detail to a preferred embodiment of the invention, an example of which is illustrated in the accompanying drawings. Wherever possible, the same reference numerals will be used throughout the drawings and the description to refer to the same or like parts.
FIG. 3 is a flow diagram of a method for operating an atomic clock or magnetometer 10 using a push pull pumping technique in accordance with the teachings of the present invention. In block 11 , atoms are generated in a vapor phase or in an atomic beam, their ground state split by the electron-nuclear hyperfine interaction. The atomic vapor can be mixed with a buffer gas or gases, such as nitrogen or any of the noble gases, or a mixture thereof. A weak external magnetic field is needed to define the quantization direction at the location of the atoms. The quantum numbers F and m are used to label the ground-state sublevels of the alkali-metal atom. Here F is a quantum number of the total spin, electron plus nuclear, of the atom, and m, is the azimuthal quantum number, the projection of the total spin along the direction of the magnetic field. The possible values of F are F=I+1/2=a or F=I−1/2=b, and the possible values of m are m=F, F−1, F−2, . . . −F.
In block 12 , to excite coherent population trapping (CPT) 0-0 resonances in alkali-metal vapors, the alkali-metal atoms in the ground state are optically pumped with light of alternating polarization. The light of alternating polarization provides photons having spin that alternates its direction at a hyperfine frequency of the atoms at the location of the atoms. Light of alternating polarization is defined within the scope of this invention as an optical field, the electric field vector of which or some component thereof at the location of the atoms alternates at a hyperfine frequency of the atoms between rotating clockwise and rotating counter-clockwise in the plane perpendicular to the magnetic field direction. In one embodiment, the polarization of the light interacting with the atoms alternates from magnetic right circular polarization (mRCP) to magnetic left circular polarization (mLCP). mRCP light is defined as light for which the mean photon spin points along the direction of the magnetic field so that an absorbed photon increases the azimuthal angular momentum of the atom by 1 (in units of h ). mLCP is defined as light for which the mean photon spin points antiparallel to the direction of the magnetic field so that an absorbed photon decreases the azimuthal angular momentum of the atom by 1 (in units of h ). For light beams propagating antiparallel to the magnetic field direction, mRCP and mLCP definitions are equivalent to the commonly used RCP and LCP definitions, respectively. However, for light beams propagating along the magnetic field direction, mRCP is equivalent to LCP, and mLCP is equivalent to RCP. In one embodiment, block 12 is performed by intensity or frequency modulating right circularly polarized (RCP) light at a repetition frequency equal to the frequency of the 0-0 resonance and combining it with similarly modulated left circularly polarized (LCP) light which is shifted or delayed relative to the RCP light by a half-integer multiple of the repetition period. Alternatively, the light of alternating polarization is generated by combining two beams of mutually perpendicular linear polarizations, wherein optical frequencies of the beams differ from each other by a hyperfine frequency of the atoms. Alternatively, the light of alternating polarization is generated by two counter-propagating beams that produce the electrical field vector at the location of the atoms which alternates at a hyperfine frequency of the atoms between rotating clockwise and rotating counter-clockwise in the plane perpendicular to the light propagation. Alternatively, the light of alternating polarization is generated by a system of spectral lines, equally spaced in frequency by a hyperfine frequency of the atoms wherein each spectral line is linearly polarized and the polarizations of adjacent lines are mutually orthogonal. Alternatively, the light of alternating polarization is generated by generating a sinusoidal intensity envelope of right circularly polarized light combined with a sinusoidal intensity envelope of left circularly polarized light that is shifted or delayed with respect to the right circularly polarized light by a half-integer multiple of a hyperfine period of the atoms.
In block 14 , detection of transmission of the light through the alkali-metal vapor is measured. For example, a photo detector can be used to measure transmission of the light through a glass cell containing the alkali-metal vapor and a buffer gas. Alternatively, fluorescence of the alkali-metal vapor is measured. Alternatively, atomic state of the alkali-metal atoms in an atomic beam is analyzed using standard methods. Push-pull optical pumping can be used to improve performance of gas-cell atomic clocks, atomic beam clocks, atomic fountain clocks and magnetometers.
FIG. 4 is a flow diagram of a method of operating a self-modulated laser 20 in accordance with the teachings of the present invention. In block 22 , one or more photonic gain media and a vapor cell are provided within a laser cavity. Example gain mediums include electronic pumped semiconductors, such as an edge-emitting laser diode or a vertical cavity surface emitting laser diode, or optically pumped gain media, such as a dye or a crystal. Necessary optics can be provided for controlling light polarization and optic bandwidth. Optics can include wave plates, polarization filters, and optical filters. In block 24 , hyperfine transitions of atoms within the vapor cell are excited by pumping them with light from said laser modulated at a hyperfine frequency. A method and system for operating an atomic clock or magnetometer can include providing the self-modulated laser comprising gain media and vapor cell within a laser cavity and exciting hyperfine transitions within the vapor cell by pumping them with light from the laser modulated at a hyperfine frequency.
FIGS. 5A-5C is an illustration of how electron spin interacts with the D 1 pumping light, how the electron spin oscillation or precession is synchronized by the push-pull pumping, and how the electron spin modulates the light absorption of the alkali-metal vapor. The D 1 pumping light tends to align the orientation of electron spin shown in FIG. 5A with the orientation of the photon spin, s shown in FIG. 5B . Push-pull pumping has light pulses interlaced by s=1 and s=−1 pulse, and the time interval between the two adjacent pulses is equal to the half period of the hyperfine cycle, 1/(2ν 00 ). The pulse width of push-pull pumping light is determined by the buffer-gas pressure inside the vapor cell. By setting the push-pull pumping beam parallel to the magnetic field (z-direction), a strong 0-0 coherence is excited, which is observed as electron spin oscillation along the z-direction. The electron spin oscillation also causes the time-dependent light absorption of the alkali-metal vapor for different photon spins as shown in FIG. 5C . FIGS. 5A-5C illustrate that there is maximum transparency of the vapor cell by employing push-pull pumping.
FIG. 6 describes the spectrum of push-pull pumping light at the frequency domain and also the spectral response of the self-modulated laser system. The push-pull pumping light of 0-0 coherence can be described as an optical comb in the spectrum. The optical comb refers to a plurality of peaks separated by ν 00 . The spacing of optical comb 30 is equal to the 0-0 hyperfine frequency. Each optical peak of optical comb 30 is linearly polarized and orthogonal to the adjacent peaks. The bandwidth of optical comb 30 is limited by the buffer-gas pressure inside vapor cell 31 and the gain bandwidth. For a self-modulated laser system, the spectral response due to different causes is summarized in FIG. 6 . Generally, the gain bandwidth is controlled by Bragg mirror 32 or alternative band-selected optical filters. An initial very small 0-0 hyperfine coherence can be excited by laser instability. Because of the presence of the hyperfine coherence, the alkali-metal vapor can scatter photons from original frequency ν o to new optical frequency ν o ±ν 00 . With favorable conditions, scattered photons with a new frequency can be increased by the photonic gain medium 33 , such as the laser diode. Therefore, an optical comb of push-pull pumping light grows inside the gain bandwidth 35 . The growth of the optical comb represents increased push-pull pumping light. A stronger push-pull pumping light generates stronger hyperfine coherence. Eventually, the laser is steadily modulated at the hyperfine frequency. It is advantageous for the spacing of the optical comb to be commensurate with the cavity mode. For laser modulating at other field-dependent hyperfine frequency, a similar optical comb is generated, but the polarization pattern of the optical comb can be different.
The optical comb generated by the self-modulated laser has comb spacing locked by the hyperfine frequency. Unlike the optical comb produced by regular comb laser, the comb spacing has to be locked to an external reference. An extended application of the alkali-vapor self-modulated laser is to produce a stable optical frequency as the optical clock. To produce a stable optical frequency of the laser light, the spectral position of the optical comb has to be locked. For an optical clock, the optical frequency of one of the comb peaks can be locked to the multiple of the hyperfine frequency by feedback controlling of the laser cavity. The optical frequency, f n , of the comb peak is stabilized by the step of feedback controlling the laser cavity to obtain f n =nν h , wherein n is an integer number, and ν h is the hyperfine frequency. Usually the optical frequency is about 10 14 -10 15 Hz and the hyperfine frequency is about 10 9 -10 10 Hz. Hence the integer number n is a value between 10 4 and 10 6 . Therefore a stable optical frequency light source is generated. Such stable light source can have a great application in any kinds of precision measurements.
FIGS. 7A-7D show possible embodiments of cavity configurations for self-modulated laser systems 40 - 70 . Four representative cavity configurations are described as examples with only one gain medium in the laser cavity. It is understood that two or more gain media are able to be incorporated inside the cavity. Self-modulated laser system 40 uses polarization gain medium 42 , such as an electronically pumped semiconductor, for example, quantum well heterojunction edge-emitting laser diode (ELD). Polarization gain medium 42 outputs light with linear polarization. In order to generate the alternation of photon spin, two quarter wave plates 43 a , 43 b are used inside laser cavity 41 . Vapor cell 44 is positioned, where the laser beam has the maximum alternation of the light polarization, between quarter wave plates 43 a , 43 b . Bragg mirror 45 and output coupler 46 recombine beams so that they emerge as a single beam of alternating circular polarization. The transmission of light through external cavity 41 is measured with photodiode 48 . In this embodiment, the cavity mode is used to achieve push-pull pumping. The effective round-trip time of push-pull pumping light is about the multiple of the hyperfine period. The laser cavity operates as a resonator to excite the self modulation. Hence, the cavity pulling effect needs to be considered. Generally, the frequency shift of the modulation frequency due to the change of the cavity length is small. For example, let Δν be the shift of the modulation frequency, and let Δf be the shift of the first harmonic cavity frequency, then it is found that Δν=αγT c Δf, where γ is the hyperfine linewidth, T c is the cavity round-trip time, and α is a factor determined by the length of the vapor cell and the vapor density.
Self-modulated laser system 50 uses polarization-diverse gain medium 52 . Light with any polarization can be amplified by this type of gain medium. Polarization diverse gain medium can be made by electronically pumped semiconductors, such as, for example, ELDs and vertical cavity surface emitting laser (VCSEL) diodes. Accordingly, this embodiment does not use quarter wave plates on either side of the vapor cell to achieve the light pumping pattern as shown in FIG. 6 . The combination of a quarter wave plate and a linear polarizer is for the photodetector to detect light with the photon spin of only s=1 or only s=−1. The commensuration of the cavity mode to the hyperfine frequency is used.
Self-modulated laser system 60 uses ring cavity 61 . In this embodiment, photons are moving to one direction. Polarization-diverse gain medium 62 is used for generating the pumping pattern shown in FIG. 6 . Narrow band optical filter 64 inside cavity 61 operates in a similar manner as the Bragg mirror described above for other configurations. Only the laser light in the frequency range of narrow band optical filter 64 is allowed to circulate in ring cavity 61 . The cycling period of ring cavity 61 is about a multiple of the hyperfine period. This embodiment has the advantage of having the least cavity-pulling effect, since the alkali-metal vapor is filled inside the entire cavity.
Self-modulated laser system 70 uses gain medium 42 , vapor cell 44 , Bragg mirror 45 , and output coupler 46 compacted together. The cavity length is much shorter so that the round-trip time is much less than the hyperfine period. In this embodiment, the generation of the push-pull pumping light relies on the intrinsic property of the gain medium. For example, by using a four-level diagram to describe the optical transitions of the gain medium, the amplifications of σ+ and σ− light depend on two different optical transitions, which have the difference of azimuthal quantum number Δm=+1 and Δm=−1. By a proper design of the relaxation properties of the spin-dependent quantum levels of the gain medium, the spontaneous push-pull pumping can be established. An advantage of this embodiment is the very compact size of the self-modulated laser system, since the cavity length is not limited by the hyperfine frequency. With a proper design of the semiconductor gain medium and the miniature laser cavity, a millimeter or sub-millimeter scale photonic clock (without local oscillator) can be achieved.
It is appreciated that the cavity configurations shown in FIGS. 7A-7D are only for examples. Other types of cavity design that realize the self modulation of the laser beam into the optical comb by using alkali-metal vapor cell is considered to be within the teachings of the present invention.
FIG. 8 , FIG. 9 , and FIG. 10 , show the results of computer simulations of the self-modulated laser system of FIG. 7A . There are three panels for each figure, and the horizontal axis is the increase of time. The top panel shows the relative carrier density inside the EDL as a function of time. The middle panel shows the laser intensity inside the cavity as a function of time. The bottom panel shows the electron-spin amplitude due to the 0-0 hyperfine coherence along the z-direction as a function of time. For FIG. 8 , it is assumed that the vapor cell contains 87 Rb with 3 atm buffer-gas pressure. The gain bandwidth is about 66 GHz. The beam diameter is 3 mm. The purity of photon spin is 90%. The loss from the output coupler is 30%. The vapor cell has optical thickness of 0.1 e-folding. Initially, a small spin oscillation is observed in the scale of 10 −8 due to the stepping up laser intensity when laser just turns on. The spin oscillation cannot maintain and die away because of the insufficient vapor density. By increasing the optical thickness of the vapor cell to 0.25 and remaining other conditions the same, it was found that a strong spin oscillation building up in about a millisecond after turning on the laser, and the light is also modulated at the hyperfine frequency as shown in FIG. 9 . FIG. 10 shows one of the simulation results for 133 CS. Cesium has high nuclear spin than rubidium. It requires high vapor density to generate spontaneous push-pull pumping inside the cavity. If the optical thickness is increased to 0.5, e-folding, and the beam diameter is reduced to 1 mm. Spontaneous push-pull pumping starts in about 0.1 millisecond after turning on the laser. For all simulations described above, the tolerance of the mismatching between the cavity mode and the hyperfine frequency is about 0.5%. Beyond the tolerance, spontaneous push-pull pumping cannot be produced.
FIG. 11 illustrates the intensity pattern along the cavity axis at different time points when a steady self modulation is built up. In this simulation, the round-trip time of the cavity is equal to three times hyperfine period. The vapor cell is placed at the center of the laser cavity. It is shown that each time the light pulse hits the vapor cell, there is maximum spin magnitude. The laser continuously outputs light pulse repeating at the hyperfine frequency. The light pulse signal can be easily converted into an electrical ticking signal as a clock. For using the self-modulated laser as the atomic clock, the gain medium and the vapor cell have to be temperature stabilized; the ambient magnetic field of the laser cavity has to be stabilized; the cavity length also has to be stabilized. The stabilization of magnetic field and the temperature can be achieved by using a magnetic-field sensor and a temperature sensor with two feedback loops to compensate the changes of those two quantities. The cavity length can be stabilized by a feedback adjustment of the cavity length to obtain a maximum light modulation.
FIG. 12 shows results of a computer simulation of the self-modulated laser system 70 of FIG. 7D . The vapor cell is assumed to have 85 Rb. The effective cavity round-trip time is 5 ps, which is much shorter than the hyperfine period, ˜330 ns, of 85 Rb. It is shown in FIG. 12 that the self-modulated laser light is alternating between σ+ polarization (solid line) and σ-polarization (dotted line). The generation of spontaneous push-pull pumping inside the vapor cell strongly depends on some physical parameters of the laser diode, such as the differential gain, the carrier lifetime, the excited-state spin relaxation rate of the gain medium, and the carrier pumping rate.
It is to be understood that the above-described embodiments are illustrative of only a few of the many possible specific embodiments, which can represent applications of the principles of the invention. Numerous and varied other arrangements can be readily devised in accordance with these principles by those skilled in the art without departing from the spirit and scope of the invention. | The present invention provides a method and apparatus for making atomic clocks or atomic magnetometers as self-modulated laser systems based on the physics of push-pull optical pumping. An atomic vapor cell is required to be in the laser cavity. With proper conditions, spontaneous push-pull optical pumping can occur inside the laser cavity. This causes the laser beam to be modulated at hyperfine-resonance frequency. With a fast photodetector, the modulated laser signal can be converted into the electrical signal, which serves as the atomic clock ticking signal or magnetometer signal. The self-modulated laser system does not use any local oscillator and the microwave circuit to lock the oscillator frequency to the hyperfine-resonance frequency, and therefore can consume less power and become more compact than conventional systems. This invention will benefit applications of time measurements and magnetic-field measurements. | 6 |
FIELD OF THE INVENTION AND RELATED ART
The present invention relates to an extruder, used for extruding materials such as aluminum alloy by an extrusion press, which can eliminate air trapped between a container and a billet to the outside of the container after a fixed dummy block or an extrusion stem is closed by a two-piece seal block and before the billet is extruded, thereby providing an end product without a blow hole of air and reducing the time.
After a billet the diameter of which is slightly smaller than the inner diameter of a container is inserted into the container, the billet is pressed against a die with an extruding stem from the rear side of the container which is called as "upsetting" so that the billet is pressed to be deformed to compress air trapped between the container and the billet. For eliminating the compressed air, the extruding stem and the container are slightly backed to release the compressed air to the atmosphere from a space between the die and the container. After that, the extrusion is started by advancing the container and the extruding stem to the original positions. The deaeration step for eliminating compressed air as mentioned above is referred to as a "verp cycle" which causes a waste of time in the extrusion cycle.
Moreover, this process remains air in a small space like a film at atmospheric pressure between the inner surface of the container and the outer surface of the billet when the container is pressed against the die after the deaeration of the verp cycle. That is, the sufficient deaeration can not be obtained by this process. This may produce blisters in an extruded product. Such an extruded product including blisters should be removed, thereby reducing the yield of end products.
Therefore, there is a method as disclosed in JPB S48-25315 to enable residual air to be easily and securely eliminated for extrusion of a billet. In this process, the residual air is eliminated by providing metallic bellows to form a sealed chamber between a container and an extruding stem, sealing by metallic packing between one end of the bellows and the container and between the other end and the extruding stem by metallic packing, and pressing the metallic packing from the outside by a cylinder using air or fluid to eliminate air in the sealed chamber to the outside.
Further, JPA S52-47556 discloses a method of vacuum deaeration from a container through a space between a dummy block and the container with the inside of the container being sealed with sealing material, through a supporting member being sealingly in contact with disc-like supporting plates, arranged in suitable positions of an extruding stem with carbon sealing material, elastically by a spring disposed between the rear wall of the container and the supporting plates.
Furthermore, JPB (utility) S55-19605 discloses an extruder provided with a two-piece seal block allowed to open and close in a direction perpendicular to the axial direction of a container. In this extruder, the inner surface of the seal block comes into close contact with the outer surface of an extruding stem when the seal block closes.
Such a two-piece seal block opens and closes along a guide plate fixed to upper and lower portions of an end face of the container at the extruding stem side. In addition, sealing members for sealing the container from the extruding stem are arranged between a cover plate and the seal block and between the extruding stem and the inner surface of the seal block, respectively. The container is provided with a deaerating groove at an upper portion thereof at the extruding stem side, thereby facilitating deaeration.
Moreover, JPA H5-245533 discloses a device comprising a rim, coming into contact with an end face of a container at an extruding stem side, and an elastic member of telescopic type sealed by edges thereof which are slidable against the extruding stem to keep a hermetically sealed enclosure to be pressed against the end face of the container over the full stroke of the extruding press device. Air within the container is vacuumed after sealed by bringing the rim into contact with the end face of the container by stretching the elastic member of the telescopic type.
In addition, there is an extruder as disclosed in U.S. Pat. No. 5,678,442 which is provided with a two-piece seal block allowed to open and close in a direction perpendicular to the axial direction of a container so that a sealing member comes into close contact with the outer surface of a ring-like projection fixed to the container and the outer surface of an extruding stem at the same time when the seal block closes.
The structures disclosed in JPB S48-25315, JPA S52-47556, JPA H5-245533, and U.S. Pat. No. 5,678,442 have following problems.
(1) Since the flexible sealing device such as a metallic bellows, a spring, or an elastic member of telescopic type, which is expandable from the extruding stem side toward the rear end of the container, is used to seal the container to completely eliminate the residual air in the container for the extrusion of the billet, it necessitates a larger deaerating space and a longer deaerating time, and the atmosphere is easily entered into the container because of insufficient sealing thereby causing the degree of vacuum lower.
(2) The sealing device is backed to a ram (a base portion of the extruding stem) side during loading the billet into the container and then the inside of the container is sealed by advancing the sealing device after the billet is completely loaded by the forward movement of the extruding stem so as to vacuum air in the container, thereby making the idle time longer for the operation of the sealing device.
(3) Since the flexible sealing device is stretched from the backmost position of the base of the extruding stem to the end face of the container, the front portion of the seal device is deformed due to the dead weight so as to make a space between the end face of the container and the seal device, thereby deteriorating the sealing performance.
(4) It needs large pressure to press the sealing device from the ram side to the container so that the container comes in sufficiently contact with the end face of the container, thereby making the structure complex.
(5) In a condition that the flexible sealing device is compressed at the backmost position, the extruding press device is longer than the conventional extruding stem (conventionally, the extending stem necessitates a length sufficiently for extruding the billet loaded in the container) for the size of the sealing device in the compressed state, thereby increasing the whole length of the extruding press and thus necessitating a wider area for installing the extruding press.
(6) According to JPA S52-47556 or JPA H05-245533, the sealing device moves relatively to the extruding stem with the sealing device being always in contact with the extruding stem, thereby easily wearing sealing materials and the contact surfaces between the sealing device and the extruding stem and decreasing their lives.
(7) In the case of (6), the front portion of the sealing device is deformed due to the dead weight, so that the sealing device easily interferes with the extruding stem, thereby further decreasing there lives.
There are following problems related to JPB (utility) S55-19605.
(8) The two-piece seal block opens and closes along the guide plate disposed on the end face of the container. The sealing members disposed between the seal block and the guide plate receive heat from the container during opening and closing of the seal block, and is exposed to high temperature (for example more than 300° C.) by holding heat in air heated in the container and moreover rubs against the guide plate, therefore significantly deteriorating the sealing members and decreasing the lives.
(9) When the extruding stem is backed to the original position after completion of extrusion of the billet, for scrapping off aluminum residues stuck to the inner surface of the container liner by the outer surface of the fixed dummy block fixed to the end of the extruding stem, the scrapped aluminum residues enter into a groove of the guide plate so that the seal block is difficult to open and close, thereby deteriorating sealing performance.
(10) Since a deaerating groove is formed in the inner surface of the container, i.e. the upper portion of the inner surface of the container liner at the extruding stem side, such a container is not allowed to be used in a general purpose extruder because of the limitation so that the container liner must be exchanged with another one without deaerating groove whenever used for another purpose, thereby taking a lot of time for exchanging container liners.
(11) The container liner is exerted with large external force during upsetting the billet so that a portion where the deaerating groove is formed is exerted with concentrated load, thereby decreasing the mechanical strength.
(12) There are many kinds of sealing methods previously improved. One of the most recently known methods is disclosed in U.S. patent application Ser. No. 656,523. In this method, a container and an extruding stem separately move relative to each other and a two-piece seal block is attached to the container. An outer sealing member of a ring-like projection and an stem sealing member are both integrally fixed to the two-piece seal block to seal the container and the stem in the same direction, respectively. Therefore, a minute space may be generated in a portion sealed by one of the sealing members so that the sealing members can not come in sufficient contact with the container or the stem, thereby making sealing performance lower.
OBJECT AND SUMMARY OF THE INVENTION
The present invention is achieved in consideration of the problems of prior art as mentioned above. It is an object of the present invention to completely eliminate air within a container by sealing the container before extruding a billet out of a die, thereby providing an extruding cycle without a step of deaerating before extruding the billet from a die, called as the verp cycle, and providing an extruder which can prevent the inclusion of air into the billet and thus prevent the deterioration of the quality and yield of end products.
For achieving the objects mentioned above, according to a first aspect, an extruder comprises an end face, at an extruding stem side, of a container having a container liner in which a billet is loaded; a two-piece seal block allowed to be opened or closed in a direction perpendicular to the axial direction of the extruding stem; and a press member. When the seal block is closed, the seal block is brought sealingly in contact with the end face of the container and the outer surface of the extruding stem simultaneously by sealing members fixed to the seal block. The press member is arranged to be moved in a direction of pressing the sealing members of the seal block against the end face of the container.
According to a second aspect, the seal block comprises base pieces and sealing material holding blocks and the sealing material holding blocks are capable of performing vacuum aspiration by engaging to a fixed dummy block or the extruding stem and is arranged slidably in the lateral direction and detachably relative to said base pieces. The sealing material holding blocks are fixed to the base pieces with engaging pins each having a stopping plate which is engaged to an engaging portion by turning the stopping plate.
The billet in the container is pressed from the rear side against the die by the extruding stem so that the billet is squeezed and air trapped between the container and the billet is compressed. The compressed air must be vacuumed form the rear side of the container before the billet is extruded from the die. In addition, air must be vacuumed from the container just before the end of the billet comes into contact with the die. According to the present invention, the air in the container is forcibly vacuumed at the extruding stem side before the billet is compressed by the extruding stem, thereby omitting the step for eliminating compressed air after the billet is compressed by the extruding stem, called as a breathing process.
Air in the container is vacuumed with the container being sealed by the seal block having a press member arranged to press the seal block against the end face of the container at the extruding stem side. For smoothly removing the air in the container, container is provided with a ring-like deaerating groove at the entrance thereof at the extruding stem side, the diameter of which is greater than that of the fixed dummy block, so that a ring-like space is formed between the inner surface of the container and the outer surface of the fixed dummy block when the billet is loaded into the container. Therefore, air trapped between the container and the billet can be easily eliminated to the outside of the container, thereby preventing the inclusion of blister and thus significantly improving the yield of the end products.
Moreover, according to the present invention, the extruding stem is sealed around the outer surface thereof while the container is sealed at the end face in the traveling direction of the extruding stem so that the end face of the container is sealed by friction force between the extruding stem and the sealing materials, thereby further ensuring the seal contact.
Since the seal block and the sealing material holding blocks are formed as separate parts and loosely fixed to each other, the sealing material holding blocks can be sealingly in contact corresponding to any misalignment of the container and the extruding stem. As a result of this, the degree of vacuum is improved so as to be 30 Torr or less, thereby preventing the inclusion of blister in an extruded product.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a system diagram of one preferred embodiment according to the present invention;
FIG. 2 is a view taken along a line 2--2 of FIG. 1;
FIG. 3 is an enlarged partial view of FIG. 2;
FIG. 4 is a plan view of a container provided with a two-piece seal block;
FIG. 5 is an enlarged partial front view of the seal block piece;
FIGS. 6a and 6b are views illustrating comparison between a case of seal block pieces in which both surfaces are glued with sealing materials, respectively and a case without sealing materials;
FIGS. 7a and 7b are views for explaining the conditions of scrapping off aluminum residues stuck on the inner surface of the container liner;
FIG. 8 is a front view of a billet loader;
FIG. 9 is a sectional view taken along a line 9--9 of FIG. 2;
FIG. 10 is a sectional view taken along a line 10--10 of FIG. 5;
FIG. 11 is a sectional view taken along a line 11--11 of FIG. 5;
FIGS. 12a and 12b are views for explaining the conditions of bringing sealing members to or out of an end face of the container at the protrusion side by press members;
FIG. 13 is an enlarged sectional view of an inlet portion of the container;
FIGS. 14a and 14b are enlarged sectional views illustrating various kinds of configurations for the inlet portion of the container;
FIG. 15 is a flow chart showing controlling procedure with time;
FIGS. 16a, 16b, 16c, and 16d are views for explaining the conditions of pushing and extruding the billet loaded into the container;
FIG. 17 is a front view of the seal block piece;
FIG. 18 is a side view taken along a line 18--18 of FIG. 17;
FIG. 19 is a front view of a sealing material holding block;
FIG. 20 is a side view taken along a line 20--20 of FIG. 19; and
FIG. 21 is a front view taken along a line 21--21 of FIG. 20.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Hereinafter, an embodiment of an extruder according to the present invention will be described with reference to the attached drawings.
As shown in FIG. 1, an end platen 32 is provided with container cylinders 33 for allowing the sliding of a container 1 comprising a container liner 1a, a container tier 2, and a container holder 1c. Reference numeral 36 designates a cylinder tube which is a part of a cylinder body, 37 designates a piston, and 38 designates a piston rod.
A die 3 is inserted and held in a die ring 5 in such a manner that the die 3 can slide to the inner surface of the die ring 5. Reference numeral 31 designates a space, as a deaeration space to be deaerated, between the inner surface of the container and the outer surface of a billet 13.
An extruding stem 14 for extruding the billet 13 is provided with a fixed dummy block 70 at the tip end thereof which can be in close contact with the inner surface of the container 1.
The description will now be made as regard to a vacuum aspirator 60 for aspirating residual air from the deaeration space 31.
The vacuum aspirator 60 for deaerating the deaeration space 31 from the extruding stem 14 side in the container 1 has a seal block which is the combination of two seal block pieces 40R and 40L arranged on the end face of the container 1 at the extruding stem 14 side. The seal block as the combination of the seal block pieces 40R and 40L has a substantially square shape as shown in FIGS. 2 and 3 and has an opening of substantially the same diameter as the extruding stem 14 at the center thereof. The rear ends of the seal block pieces 40R and 40L are fixed to tips of piston rods 43Ra and 43La of cylinders 43R and 43L, respectively.
According to the stroke of the piston rods 43Ra and 43La, the seal block pieces 40R and 40L move in a direction perpendicular to the axial direction of the container 1 along guide rods 42UR, 42UL and 42DR, 42DL which are disposed above and below the seal block.
The seal block pieces 40R and 40L are provided with upper guide legs 62R and 62L disposed above the seal block pieces, respectively. The guide rods 42UR and 42UL are fixed to upper guide legs 62R, 62L, respectively. Through pipes 64UR and 64UL are slidably inserted onto the guide rods 42UR and 42UL, respectively.
The seal block pieces 40R and 40L are also provided with lower guide legs 63R and 63L disposed beneath the seal block pieces, respectively. The guide rods 42DR and 42DL are fixed to the lower guide legs 63R and 63L, respectively. Through pipes 64DR and 64DL are slidably inserted onto the guide rods 42DR and 42DL, respectively. The through pipes 64UL and 64DL function for the seal block piece 40L while the through pipes 64UR and 64DR function for the seal block piece 40R.
For preventing air infiltration between the contact surfaces 40A of the seal block pieces 40R and 40L when the seal block pieces 40R and 40L come in contact with each other i.e. the seal block is closed, the contact surfaces 40A are provided with sealing members 46 (sheet-like sealing materials) attached thereon as shown in FIG. 6a.
For example, the sealing members 46 are preferably sponge-like sealing materials, having heat resistance and resiliency, made of silicon rubber or fluoro-rubber.
When the seal block is closed, the sealing members 46 attached to the contact surfaces 40A of the seal block pieces 40R and 40L come in sealing contact with each other. As shown in FIGS. 9 through 12a and 12b, sealing members 41 disposed on the surfaces of the seal block pieces 40R, 40L at the container 1 side come in sealing contact with the end face 51 of the container liner 1a and sealing members 44 come into sealing contact with an outer surface of the fixed dummy block 70 or the extruding stem 14.
The sealing members 41 and 44 are preferably made of heat resistant and high deformable material, such as relatively hard string-like silicone rubber and string-like fluoro-rubber. Though the sealing members 41 and 44 are each disposed doubly, not single, with a space therebetween as shown in FIGS. 9 through 12a and 12b in order to prevent air infiltration from the outside during the vacuum aspiration, the invention is not limited thereto so that the sealing members may be each disposed triply or more, thereby providing perfect deaeration.
In case where the seal block pieces 40R, 40L are not provided with the sealing members 46 as shown in FIG. 6b, as bringing the seal block pieces 40R and 40L close to each other, the sealing members 44 first come into contact with the fixed dummy block 70 or the extruding stem 14, then the seal block pieces 40R and 40L are further close to each other, and come into sealing contact with each other. During this process, the sealing members 44 are pressed against the outer surface of the fixed dummy block 70 or the extruding stem 14 and move in the direction of arrows of FIG. 6b. Therefore, the sealing members 44 are deformed as shown in FIG. 6b due to the friction exerted from the outer surface of the fixed dummy block 70 or the extruding stem 14 so that spaces S are formed between the contact surfaces of the sealing members 44.
In case where the sealing members 46 made of sponge-like soft rubber (each 3 mm in thickness) are attached to the contact surfaces 40A of the seal block pieces 40R and 40L as shown in FIG. 6a, the sealing members 46 prevent the formation of the spaces S between the contact surfaces when the seal block is closed.
The description will now be made as regard to the structure of an operating device 140. The operating device 140 comprises the seal block pieces 40R and 40L, base pieces 142R, 142L (FIGS. 3, 5), press members 144 (FIGS. 9, 12a, 12b), and engaging pins 158 (FIG. 9). As shown in FIG. 5, the base pieces 142R and 142L, each having a configuration like a half of octagon, are surrounding the seal block pieces 40R and 40L as also shown in FIG. 9.
As shown in FIGS. 2, 3, and 9, the base pieces 142R, 142L are fixed to the upper guide legs 62R, 62L and the lower guide legs 63R, 63L, respectively. As shown in FIG. 3, each base piece 142R, 142L are provided with press cylinders 148UR and 148DR, 148UL and 148DL disposed on an upper portion and a lower portion thereof, respectively. As shown in FIG. 9, each press member 144 is threaded onto the tip of a cylinder rod 149 of each press cylinder. Each press member 144 comprises a base block 144a, a small-diameter portion 144b, and a press portion 144c.
As shown in FIG. 17, each of the base pieces 142L and 142R constituting the seal block body has a substantially C-like configuration and is provided with cylinder beds 170 at the upper and lower portions thereof. The base pieces 142L and 142R are also each provided with pin mounting beds 172 each adjacent to the cylinder beds 170 as shown in FIG. 18. Sealing material holding blocks 58L, 58R (FIG. 19) are attached to the base pieces 142L, 142R, respectively by sliding them in the lateral direction. The engaging pins 158 each having a stopping plate 160 (FIG. 9) fixed on the end thereof are inserted into through holes 168a formed in the holding blocks 58L, 58R and holes 168b formed in the base pieces 142L, 142R and then turned by 90°, thereby engaging the stopping plates 160 to engaging portions 162 (FIG. 9) of the base pieces 142R, 142L. In this manner, the sealing material holding blocks 58L, 58R are fixed to the base pieces 142L, 142R.
As shown in FIGS. 19 through 21, the sealing material holding blocks 58R, 58L are provided with grooves 174, 176 for mounting the sealing members 41, 44. Fitted in the grooves 174 are the sealing members 44 and fitted in the grooves 176 are the sealing members 41. Arranged on the sealing material holding blocks 58R, 58L are sealing material beds 182R, 182L each formed in a semicircular configuration fit to the outer surface of the fixed dummy block 70 or the extruding stem 14.
The sealing material holding blocks 58R, 58L are provided with notches 150 (FIGS. 9, 19) formed in both end portions thereof. For attaching and detaching the sealing material holding blocks 58L. 58R relative to the base pieces 142L, 142R in a short time, the small-diameter portions 144b of the press members 144 are engageable to the notches 150, respectively. As shown in FIGS. 12a, 12b, the press member 144 is exerted with pressure F developed by air pressure supplied and exhausted in the press cylinder 148 so that the base block 144a presses the seal block piece 40R, 40L to press the sealing members 41 against the end 51 of the container liner 1a, thereby providing high sealing performance.
Guide liners 154 are disposed for allowing the press members 144 to reciprocate smoothly between the base pieces 142R, 142L and the sealing material holding blocks 58R, 58L.
The sealing material holding blocks 58R, 58L and the base pieces 142R, 142L essentially constituting the seal block pieces 40R, 40L can be easily disassembled by pulling off the engaging pins 158. The replacing of the sealing material holding blocks 58R, 58L with spare ones is particularly frequently needed due to damage or wearing of the sealing members 41, 44, 46. Since the replacing of the sealing material holding blocks 58R, 58L can be completed, for example, only 3-4 minutes and then the extrusion can be successively proceeded, the yield of end products is little reduced.
As shown in FIG. 11, for eliminate residual air in the space formed between the billet 13 and the container liner 1a to the outside the container when the billet 13 is loaded into the container 1, each seal block piece 40R, 40L is provided with a deaerating hole 45 in which a coupler 164 is arranged. A flexible pipe line 8a (FIGS. 1, 2) can be attached to the coupler 164. Reference numeral 166 designates a blind plug disposed on the way of the deaeration hole 45.
When the seal block pieces 40R, 40L return to the backmost positions thereof as shown by solid lines in FIG. 2, a billet loader 111 (described later) can move out and in with the billet 13 being placed thereon.
The deaerating hole 45 can communicate with a vacuum tank 20 through the flexible pile line 8a, an electromagnetic switch valve 90, and a fixed pile line 8b.
As shown in FIG. 9 and FIGS. 12a, 12b, the container tier 2 is provided with a circular concave portion 50 concentric with the container liner 1a, into which a donut-like heat insulator 47 is fitted. The heat insulator 47 has a function for reserving heat of the container. Since the sealing for the end face of the container 1 is achieved by a method of bringing the sealing members into sealingly contact with the end face of the container liner 1a, the seal block can be easily mounted to general purpose press machines.
As shown in FIG. 13, the inner diameter Y of a loading opening 126 of the container is larger than the inner diameter X of the container liner 1a.
Even when a tip large portion 49 of the fixed dummy block 70 is increased in diameter by aluminum residues adhering on the outer surface of the tip large portion 49 during extrusion so as to, for instance, have the same diameter as the inner diameter X of the container liner 1a, air within the container 1 can be easily eliminated because of an annular space formed between X-Y.
The entrance of the end face 51 of the container liner 1a is tapered in such a manner that its diameter is increased toward the end face so that the tip large portion 49 of the fixed dummy block 70 can smoothly pass and press the billet 13 into the container 1 from the end face of the extruding stem 14.
As shown in FIGS. 14a and 14b, the inner surface of the entrance of the container liner 1a at the end face 51 may be provided with protrusions 80a.
There is no cover plate nor guide rail for the close/open motion of the seal block pieces 40R, 40L. This is because the seal block pieces 40R, 40L are opened with the guide rods 42U, 42D being guided by the through pipes 64UL, 64UR, 64DL, 64DR.
The above structure facilitates the exchange of the container tire 2 and the container liner 1a. In addition, in case of scrapping off aluminum residues stuck on the inner surface of the container liner 1a by the outer surface of the fixed dummy block 70 when the extruding stem 14 returns to the original position after extruding the billet 13, the scrapped aluminum residues just fall down from the end face 51 of the container liner 1a as shown in FIG. 7. The residues do not enter into a groove of the guide plate as the prior art. Therefore, the close motion of the seal block pieces 40R, 40L is always well and the sealing performance is also well.
The description will be made as regard to the billet loader 111 with reference to FIG. 2 and FIG. 8.
The billet loader 111 shown in FIG. 2 and FIG. 8 comprises a first billet loader 111a and a second billet loader 111b for supplying the billet 13 as an extrusion material to the loading opening 126 of the container 1. The billet 13 sent by a billet carrier (not shown) disposed at either side of the extruder is clamped one by one and lifted to the level of the loading opening 126.
The billet loader 111 is disposed to face the billet carrier and is provided with a swing arm 128 which is pivotable along a plane perpendicular to the extruding axis of the extruder.
One end of the swing arm 128 is pivotally mounted to a central shaft 130 disposed outside a lower tight rod 129 of the extruder. The swing arm 128 is bent in a V-like shape with a high angle to prevent interference with the tight rod 129 during swinging and extends from a position below the lower tight rod 129 toward a lower portion of the container 1. The other end of the swing arm 128 reciprocates between the board (not shown) of the billet carrier and the loading opening 126 of the container 1 by the pivotal movement of the swing arm 128.
The swing arm 128 is connected to a hydraulic cylinder 132 which drives the swing arm 128 by its rectilinear motion.
The other end of the swing arm 128 is provided with a billet holder 133 for clamping the billet 13. The billet holder 133 has beds 134 for supporting the bottom of the billet 13 in a loading position.
As for the structure of the extruding stem 14, there are two cases: where the fixed dummy block 70 and the extruding stem 14 are connected through a bayonet block 72, that is, "bayonet connection" and where the fixed dummy block 70 is directly connected to the extruding stem 14 by screwing.
The bayonet connection is employed in this embodiment.
The fixed dummy block 70 is fixed to the front surface of the extruding stem 14 and slidably disposed in the container 1. The rear end of the extruding stem 14 is fixed to a cross head 75 through a stem holder 73 and a pressure ring 74 as shown in FIG. 1.
The bayonet block 72 is disposed on the front surface of the extruding stem 14. The tip of a connection rod 76 having a circular section is screwed into the rear half of the bayonet block 72. The rear end of the connection rod 76 is a large-diameter portion 76a which is fixed to a hole formed in the rear end portion of the extruding stem 14 in such a manner that tapered surface therebetween are engaged each other.
Hereinafter, the deaerating method will be described with reference to FIG. 15 and FIGS. 16a-16d. As shown in FIG. 1, the piston 37 is first moved in the left direction by supplying pressure oil to a rod side of the container cylinder 33 to advance the container 1, which is now spaced apart from the die 3, so that the container 1 comes into contact with the die 3.
After that, the billet loader 111, on which the billet 13 is now placed, rises up to hold the billet 13 at the central position. As the extruding stem 14 is advanced ((1) of FIG. 15, FIG. 16a), the billet 13 is pressed into the container 1 (FIG. 16b). The inside of the vacuum tank 20 is already vacuum state, e.g. 0-5 Torr, by the vacuum pump 21. The billet 13 is pressed into the container 1 according to the advance of the extruding stem 14. The extruding stem 14 stops for a moment where the tip large portion 49 of the fixed dummy block 70 reaches the large-diameter portion of the entrance of the container liner 1a.
At the same time when the extruding stem 14 stops for a moment ((2) of FIG. 15), the cylinders 43 are actuated to start the advance movement of the seal block pieces 40L, 40R ((3) of FIG. 15). The seal block pieces 40L, 40R are advanced to the forward-most positions so as to bring the sealing members 44 into contact with the outer surface of the extruding stem 14. In this state, the close motion of the seal block pieces 40L, 40R is performed ((4) of FIG. 15, FIG. 16c). The sealing members 41 are strongly pressed against the end face 51 of the container liner 1a by the press members 144, thereby sealing the container 1 relative to the extruding stem 14. The deaeration space 31 between the container 1, the die 3, and the billet 13, therefore, communicates with the vacuum aspirator 60 ((5) of FIG. 15).
The deaeration is not started simultaneously with the sealing. The vacuum aspirator 60 is actuated after Tu seconds (about 0.2 seconds) from the sealing by using a timer (not shown) to excite the electromagnetic switch valve 90, thereby starting the vacuum aspiration in a state allowing the communication between the inside of the container 1 and the vacuum tank 20 ((6) of FIG. 15). Air in the sealed space flows through the deaerating holes 45 of the seal block pieces 40L, 40R and is vacuumed into the vacuum tank 20 through the pipe line 8a, the electromagnetic switch-valve 90, and the pipe line 8b. Once the electromagnetic switch valve 90 is excited, residual air in the container 1 is vacuumed by the vacuum tank 20 and, just after 0.2-0.5 seconds, the inside of the container 1 becomes 5-30 Torr. In this manner, the residual air in the container can be quickly and sufficiently exhausted.
The extruding stem 14, which has been stopped, is advanced again ((7) of FIG. 15) after Tr seconds (about 0.2-0.3 seconds) from the start of the vacuum aspiration by the vacuum aspirator 60, using the timer (not shown). The re-advance of the extruding stem 14 causes the billet 13 loaded in the container 1 to be pressed so that the distal end of the billet 13 comes into contact with the die 3. When the hydraulic pressure in the side cylinder becomes a predetermined value, the press working changed to a main cylinder (not shown). Thus, the upsetting is completed (FIG. 16d). The rear end of the billet 13 is squeezed because the advance of the billet 13 is blocked by die 3. Following that the extrusion will be started.
The pressure in the container 1 rises up until the completion of the upsetting. As the pressure in the container 1 exceeds the preset pressure of the pressure switch PS (not shown) ((8) of FIG. 15), the timer (not shown) starts to count Ts seconds (about 5-6 seconds) and after Ts seconds the vacuum aspiration in the container 1 by the vacuum aspirator 60 is stopped ((9) of FIG. 15). After stopping the vacuum aspiration, the timer starts to count Tv seconds (about 0.2 seconds). After Tv seconds, the press members 144, which strongly press the sealing members 41 arranged on the end face of the seal block pieces 40R, 40L against the end face of the container liner 1a with the protrusions 80, is moved backward to cancel the sealing between the extruding stem 14 and the container 1 ((10) of FIG. 15).
At the same time of the backward movement of the press members 144, the seal block pieces 40R, 40L are started to be returned ((11) of FIG. 15). The seal block pieces 40R, 40L are returned to the original positions and are stopped ((12) of FIG. 15).
During this operation, the forward movement of the extruding stem 14 is continued without stopping so that the billet 13 is squeezed. After that, the extrusion by the extruding stem 14 is still continued. Upon completion of the extrusion, the extruding stem 14 is returned to start a next extrusion cycle.
When the sealing members 41, 44, 46 are damaged or wear away so that they can not provide predetermined degree of vacuum, the sealing material holding blocks 58R, 58L should be quickly replaced with spare ones. In this case, each stopping plate 160 is turned to the position, where it can be removed from the engaging portion 162, and then took away. After that, the sealing material holding block 58R (or 58L) damaged is removed and a spare sealing material holding block 58R (or 58L) is inserted in such a manner that the sealing material holding block 58R (or 58L) is superposed on the base plate 142R (or 142L). Then, each engaging pin 158 is inserted and each stopping plate 160 is turned to be engaged to the engaging portion 162. In this manner, the extrusion of billet 13 by advance of the extruding stem 14 can be started again.
As apparent also from the above description, the present invention has the following effects.
(1) The two-piece seal block arranged on the end face, at the extruding stem side, of the container is closed in a direction perpendicular to the axial direction of the extruding stem and the press member further strongly presses the sealing material against the end face of the protrusion of the container, thereby making the sealing performance higher and providing sufficient deaeration, without making the whole length of the extruder longer.
(2) The inside of the container can be sufficiently deaerated before the extrusion, thereby providing end products without blow hole of air and thus improving the quality and yield of end products.
(3) The sealing by the seal block is performed in a short time, thereby reducing the idle time.
(4) The seal block is spaced apart from the ring-like protrusion and the extruding stem until the time immediately before the seal block is closed, thereby making the lives of the sealing members longer.
(5) Even when aluminum residues are scrapped off by the outer surface of the fixed dummy block when the extruding stem is returned to the original position after extruding the billet, the scrapped aluminum residues just fall down out of the container, not enter into such a groove along which the two-piece block is opened as the prior arts, thereby keeping the higher sealing performance.
(6) This structure does not require the verp cycle as the prior art, thereby reducing the idle time.
(7) Even when the sealing members for keeping the degree of vacuum are damaged or wear away and are thus needed to be replaced, time for replacing them is short, thereby preventing the deterioration of the yield of end products. | An extruder is formed of a container having a container liner for receiving a billet therein, an extrusion stem situated near the container for disposing the billet into the container, and a two-piece seal block installed between the container and the extrusion stem for sealing therebetween. The seal block is formed of two seal block sections for sandwiching the extrusion stem therebetween. Each seal block section includes a base piece having a press member, and a holding block detachably attached to the base piece to be moved by the press member and having a first sealing member facing the extrusion stem and a second sealing member facing the container. A moving device is attached to the seal block sections for moving the seal block sections relative to the extrusion stem. The holding block is urged to the extrusion stem by the moving device, and to the container by the press member to thereby seal between the container and the extrusion stem. | 1 |
RELATED APPLICATIONS
[0001] This patent application is a continuation of International Application No. PCT/JP2010/057121, filed on Apr. 22, 2010, entitled, “Device and Method for Recovering Lithium,” the contents and teachings of which are hereby incorporated by reference in their entirety.
FIELD
[0002] The present invention relates to a lithium recovery apparatus for recovering lithium and a method for such a recovery, and especially to a lithium recovery apparatus, which permits an effective separation recovery of lithium with high purity, as well as an apparatus for such a recovery.
BACKGROUND
[0003] Lithium is rare non-ferrous metal, which has been widely used in a secondary battery, a special glass, a single-crystal oxide, an aircraft, a spring material, etc. Global demands for lithium have recently increased along with demand expansion of information technology devices. Demands for the lithium will further increase. Producing countries of the lithium are concentrated, and it is therefore desirable to recover the lithium in a stable manner in countries having no mineral resources for lithium.
[0004] As a conventional lithium recovery method, there is for an example a method in which adsorption and desorption of lithium ion in an aqueous solution are carried out by using manganese oxide electrodes, which have been obtained by condensing lithium or magnesium from lithium-bearing manganese oxide or magnesium-bearing manganese oxide, respectively, and varying an applied voltage (see Japanese Patent Provisional Publication No. H06-088277). In addition, as a conventional lithium recovery method, there is for an example a method comprising the steps of bringing an adsorbent, which has been prepared from raw materials of β-diketone, neutral organic phosphorous compound and vinyl monomer having a cyclic structure, into contact with an aqueous solution containing at least lithium, sodium and calcium, in a pH value of 7 or more of the solution to cause metallic components in the solution to be adsorbed on the above-mentioned adsorbent, and then bringing them into contact with water having a pH value of 4±1.5 to desorb the lithium (see Japanese Patent Provisional Publication No. 2009-161794).
SUMMARY
[0005] However, the conventional lithium recovery method has a problem of an increased cost required for a scale-up operation on an industrial basis in case of applying an electrochemical technique. In addition, the conventional lithium recovery method has a problem of low purity of lithium, due to an existence of organic substances with the lithium as recovered in case of utilizing an organic solvent.
[0006] An object of the present invention, which was made to solve the above-mentioned problems, is to provide a lithium recovery apparatus, which permits to recover effectively lithium having a high purity upon a separation recovery of lithium and to perform an easy scale-up operation on an industrial basis to save costs, as well as a method for such an recovery.
[0007] A lithium recovery apparatus according to the present invention comprises: an adsorption unit that causes a lithium solution containing lithium to flow into a column comprising a bioabsorbable membrane and/or manganese oxide to cause the lithium to adsorb on the column; an elution unit that causes hydrochloric acid to flow into the column to elute the lithium adsorbed on the column, to prepare a lithium elution liquid containing the hydrochloric acid and lithium chloride; a condensing unit that subjects the lithium elution liquid prepared by the elution unit to a heating treatment and a hydrochloric acid solution removing treatment in a cyclic manner to condense a lithium chloride solution obtained by the treatments; and a collecting unit that causes sodium carbonate to be added to the lithium chloride solution obtained by the condensing unit, to collect the lithium in a form of a solution of a condensed lithium precipitation containing lithium carbonate and sodium chloride.
[0008] According to the lithium recovery apparatus of the present invention, the condensing unit subjects the lithium elution liquid prepared by the above-mentioned elution unit to the heating treatment in a cyclic manner to vaporize the hydrochloric acid and causes the vapor to be condensed to prepare the lithium chloride solution in condensation, and the collecting unit causes the sodium carbonate to be added to the lithium chloride solution obtained by the condensing unit as mentioned above, and permits to collect the lithium in a form of precipitate containing the lithium carbonate and the sodium chloride. It is therefore possible to condense the lithium in a multilayer process, thus separating and recovering the lithium having a high purity in an easy manner.
[0009] The lithium recovery apparatus according to the present invention comprises may further comprise where appropriate: a hydrochloric acid recycling unit that subjects a residual liquid of the lithium chloride solution condensed by said condensing unit to a cooling treatment to recycle the hydrochloric acid obtained through said cooling treatment as the hydrochloric acid as flown in said elution unit. In the lithium recovery apparatus according to the present invention, the hydrochloric acid recycling unit causes the residual liquid of the lithium chloride solution condensed by the condensing unit as described above to vapor, causes the vapor as obtained through this vaporization to cool and condense to create hydrochloric acid, and causes the hydrochloric acid obtained from the residual liquid as mentioned above to be recycled as the hydrochloric acid as flown in the elution unit as mentioned above. It is therefore possible to control an amount of the hydrochloric acid as initially supplied, thus leading to reduction in costs associated with the hydrochloric acid and effective utilization of the sources.
[0010] The lithium recovery apparatus according to the present invention comprises may further comprise where appropriate: a supply unit that causes any one of seawater, salt lake water, geothermal water or a waste-dissolved solution, which contains the lithium, to pass through a filter membrane to prepare the lithium solution in the adsorption unit. In the lithium recovery apparatus according to the present invention, the supply unit causes any one of the seawater, the salt lake water, geothermal water or the waste-dissolved solution, which contains the lithium, to pass through the filter membrane to prepare the lithium solution in the adsorption unit. It is therefore possible to enhance the adsorption efficiency of the lithium in the above-mentioned adsorption unit, thus performing the adsorption of the lithium in higher concentration.
[0011] The lithium recovery apparatus according to the present invention comprises may further comprise where appropriate: a cleaning unit that washes the column, with water, in which the lithium has been eluted with the hydrochloric acid in the elution unit. In the lithium recovery apparatus according to the present invention, the cleaning unit washes the column, with water, on which the lithium has been adsorbed by the above-mentioned adsorption unit. It is therefore possible to enhance the adsorption efficiency of the lithium in the above-mentioned adsorption unit by maintaining the adsorption capability of the column, thus performing the adsorption of the lithium in higher concentration.
[0012] The lithium recovery apparatus according to the present invention comprises may further comprise where appropriate: a lithium solution mixing unit that causes a pure lithium carbonate solution to be added to the condensed lithium solution prepared by the collecting unit. In the lithium recovery apparatus according to the present invention, the lithium solution mixing unit causes the pure lithium carbonate solution to be added to the condensed lithium solution prepared by the collecting unit. It is therefore possible to increase further the concentration of the lithium from the condensed lithium solution, thus performing recovery of the lithium in further high concentration.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] FIG. 1 is a schematic descriptive view of a lithium recovery apparatus according to the present invention; and
[0014] FIG. 2 is a flowchart of the lithium recovery method according to the present invention.
DETAILED DESCRIPTION
[0015] Now, description will be given below of an embodiment of the lithium recovery method of the present invention with reference to FIGS. 1 and 2 . FIG. 1 is a schematic descriptive view of the lithium recovery apparatus according to the present invention and FIG. 2 is a flowchart of the lithium recovery method according to the present invention.
[0016] The lithium recovery apparatus according to the present invention includes a supply unit 1 that causes any one of seawater, salt lake water, geothermal water or a waste-dissolved solution, which contains the lithium, to pass through a filter membrane to prepare a lithium solution containing the lithium; an adsorption unit 2 that causes the lithium solution to flow into a column made of manganese oxide to cause the lithium to adsorb on this column; an elution unit 3 that causes hydrochloric acid to flow into this column to elute the lithium adsorbed on the column, to prepare a lithium elution liquid containing the hydrochloric acid and lithium chloride; a cleaning unit 4 that washes the column, with water, in which the lithium has been eluted with the hydrochloric acid in the elution unit 3 ; a condensing unit 5 that subjects the lithium elution liquid prepared by the elution unit 3 to a heating treatment to vapor the hydrochloric acid in a cyclic manner to condense the vapor to prepare a lithium chloride solution through condensation; a collecting unit 6 that causes sodium carbonate to be added to the lithium chloride solution obtained by the condensing unit 5 , to collect the lithium in a form of a solution of a condensed lithium precipitation containing lithium carbonate and sodium chloride; and a hydrochloric acid recycling unit 7 that subjects a residual liquid of the lithium chloride solution condensed by the condensing unit 5 to a cooling treatment to recycle the hydrochloric acid obtained through the cooling treatment as the hydrochloric acid as flown in the elution unit 3 , as shown in FIG. 1 .
[0017] The supply unit 1 is provided with a storage tank 11 , which is made of a stainless steel to store seawater, salt lake water, geothermal water or a waste-dissolved solution, as a lithium containing solution, and a filter 12 having a multiple structure. This filter 12 has at least the two-layer structure and is capable of removing impurities, which are included in the lithium containing solution and have a large particle size.
[0018] The adsorption unit 2 is provided with a plurality of column adsorption tanks 21 , which are made of a stainless steel and filled with a bioabsorbable membrane and/or manganese oxide on which the lithium adsorbs selectively. The column adsorption tanks 21 are described as a plurality of tanks to reduce an amount of treatment by each tank. However, a single tank may be used. As material with which the column adsorption tank 21 is filled, there may be used various kinds of material having a particle size of from 100 μm to 1 mm in the form of fine particles or membranes. It is preferable to use, as the column adsorption tank 21 , a column, which is filled with a λ-type manganese oxide (in the form of fine particles or membranes) having a high lithium adsorption capability, and there may be used a lithium adsorbent as disclosed for example in Japanese Patent No. 3937865.
[0019] The elution unit 3 is provided with a hydrochloric acid tank 31 for storing hydrochloric acid and an elution liquid tank 32 for storing a solution for elution from the column adsorption tank 21 . The cleaning unit 4 is provided with a pure water manufacturing plant 41 for manufacturing pure water and a pure water tank 42 for storing the pure water manufactured by the pure water manufacturing plant 41 . As such a pure water manufacturing plant 41 , there may be used various kinds of general pure water manufacturing plants, and there may be used for example a water supply/treatment system disclosed by the present inventor (Japanese Patent Provisional Publication No. 2010-029750).
[0020] The condensing unit 5 includes a condensing tank 51 , which is made of a stainless steel and stores the elution liquid from the elution liquid tank 32 , a drain separator 52 for separating/removing the hydrochloric acid solution contained in the vapor from a stock solution of this condensing tank 51 , a liquid phase tank 53 , which is made of a stainless steel and stores the hydrochloric acid solution in liquid phase as separated/removed through the drain separator 52 , and a heating section 54 to heat the stock solution of the condensing tank 51 and cause it to flow back into the condensing tank 51 . As the drain separator 52 , there may be used one of various kinds of drain separators as offered commercially. However, there may be used an in-line type drain separator, which is incorporated between a compressor and a piping, or a drain separator in which a baffle plate is placed in the piping to remove the hydrochloric acid solution, which flows into a trap from a branching tubule. The heating section 54 may conduct a heating step utilizing a surface seawater having a high temperature in addition to function of a boiler, thus constituting an apparatus with reduced costs and environmental load by utilizing seawater as an immediate inexhaustible source.
[0021] The collecting unit 6 is provided with a soda ash tank 61 , which is made of a stainless steel and stores sodium carbonate (Na 2 CO 3 ), a filter 63 for filtering the above-mentioned hydrochloric acid solution in liquid phase to which the above-mentioned sodium carbonate has been added, and a collecting tank 62 , which is made of a stainless steel and stores a lithium solution, which is obtained through reaction with the sodium carbonate as filtered. The hydrochloric acid recycling unit 7 is provided with a condenser 71 for condensing the hydrochloric acid solution, a cooling section 72 for conducting the cooling step, and a hydrochloric acid tank 73 for storing hydrochloric acid obtained from the above-mentioned condenser 71 . As the above-mentioned cooling section 72 , there may be used a deep seawater having a low temperature of the seawater. In this case, this may constitute an apparatus with reduced costs and environmental load by utilizing the seawater.
[0022] Now, description will be given below of the lithium recovery method according to the embodiment with the structure as described above. FIG. 2 shows a flow of the lithium recovery method according to the present invention.
[0023] Supply Step
[0024] As shown in FIG. 2 , a lithium containing solution containing lithium (for example, any one of seawater, salt lake water, geothermal water or a waste-dissolved solution) is stored in the storage tank 11 (S 1 ). The lithium containing solution as stored is caused to pass through the filter 12 (S 2 ). This filter 12 can remove impurities having a large particle size.
[0025] Adsorption Step
[0026] The lithium containing solution, which has passed through the filter 12 , is caused to flow into a vacant column adsorption tank 21 of the plurality of column adsorption tanks 21 (S 3 ). Such a flow causes the lithium contained in the lithium containing solution to adsorb specifically selectively on the column. In case where an amount of inflow does not reach a predetermined value and a predetermined period of time does not lapse (S 4 ) concerning the flowing step, the system returns to Step S 3 to cause this lithium containing solution to continuously flow into the column adsorption tank 21 . In case where an amount of inflow has reached the predetermined value or the predetermined period of time lapsed (S 4 ) concerning the flowing step, the flowing step is halted (S 5 ).
[0027] Elution Step
[0028] The hydrochloric acid in an amount of 1 mol/L is flown from the hydrochloric tank storing it into the column adsorption tank 21 to elute the lithium (S 6 ). This Step S 6 causes the lithium adsorbed on the column adsorption tank 21 to react with the hydrochloric acid, as shown by Formula 1 as indicated below, to elute an elution liquid as a mixed solution of lithium chloride (LiCl) and the hydrochloric acid (HCl). The thus obtained elution liquid is stored in the elution liquid tank 32 (S 7 ). In case where the whole amount of the lithium containing solution stored in the storage tank 11 is not discharged from the column adsorption tank 21 even after completion of Step S 1 (S 8 ), the system returns to Step 7 as mentioned above again to store continuously it into the elution liquid tank 32 .
[0000] Li + +HCl→LiCl+H + (Formula 1)
[0029] Cleaning Step
[0030] In case where the whole amount of the lithium containing solution is discharged from the column adsorption tank 21 (S 8 ), the cleaning step and the condensation step are carried out simultaneously. First, in the cleaning step, the column placed in the column adsorption tank 21 is washed with pure water (S 9 ). This cleaning step can be carried out by storing the pure water, which has been manufactured by the pure water manufacturing plant 41 , in the pure water tank 42 and flowing it into the column adsorption tank 21 . After completion of the cleaning step, one of the plurality of columns as washed is selected (S 10 ) and the system returns to Step S 3 as mentioned above and the step in S 3 and the subsequent step are repeated. The combination of the plurality of columns in this manner permits to use the column, which is always kept clean through the cleaning step with pure water.
[0031] Condensation Step
[0032] In case where the whole amount of the lithium containing solution is discharged from the column adsorption tank 21 in Step S 8 , the lithium chloride containing solution as prepared is stored in the condensation tan k 51 , and then heated at a temperature of 90° C. with the use of the heating section 54 under a reduced pressure of about 0.8 atmospheres, and then flown back into the condensation tank 51 to circulate the lithium chloride containing solution (S 11 ) in the condensation step. The solution stored in this condensation tank 51 is supplied into the drain separator 52 to remove the hydrochloric acid solution, and the resultant in liquid phase is stored as the lithium containing solution in the liquid phase tank 53 (S 12 ).
[0033] Collecting Step
[0034] In case of the liquid phase as separated by the drain separator 52 through Step S 11 (S 13 ), soda ash from the soda ash tank 61 , which stores the soda ash (sodium carbonate (Na 2 CO 3 )), is added into the lithium containing solution stored as the liquid phase in the liquid phase tank 53 (S 14 ). The solution with it as added is passed through the filter 63 for filtration (S 15 ). The adding step in Step S 14 causes lithium carbonate (Li 2 CO 3 ) to precipitate mainly in the solution after the filtration and sodium chloride (NaCl) to coprecipitate partially therein. The lithium containing solution containing such precipitates is collected in the collecting tank 62 (S 16 ).
[0035] Hydrochloric Acid Recycling Step
[0036] In case of the gas phase as separated by the drain separator 52 in Step S 13 as described above, the gas containing the hydrochloric acid is subjected to depressurization by the condenser to about 0.8 atmospheres for cooling condensation (S 17 ). A concentrated hydrochloric acid solution as prepared through this fooling condensation is flown back to the hydrochloric acid tank 31 , which has been used in the elution step (S 18 ). It is preferable to maintain the concentration of the hydrochloric acid in the hydrochloric acid tank 31 of about 1 mol/l, as the concentration in which the lithium adsorbed on the column is apt to elute effectively. After the flowing back, the system returns to Step S 6 as described above and the step in S 6 and the subsequent step are repeated. Such a flowing back in Step S 18 makes it possible to control an amount of the hydrochloric acid as initially supplied, which is required for the hydrochloric acid tank 31 , thus leading to reduction in costs associated with the hydrochloric acid and effective utilization of the sources.
[0037] In Step S 14 as described above, it is possible to prepare lithium carbonate (Li 2 CO 3 ) with increased concentration by mixing a pure (100%) lithium carbonate (Li 2 CO 3 ) solution with the lithium containing solution collected in the collecting tank 62 .
[0038] In the above description, there are used the supply unit 1 , the cleaning unit 4 and the hydrochloric acid recycling unit 7 . However, even in case where these units are not used, it is possible to perform recovery of lithium with higher purity in comparison with the conventional known lithium recovery method, although the recovery concentration of the lithium is decreased and a cost for the hydrochloric acid increases.
[0039] Results of experiments, which were made in accordance with the present invention, will be described below as an example. However, this example does not limit the scope of the present invention.
Example
[0040] The recovery of the lithium was made for seawater taken in the coast of the Japan Sea with the use of the lithium recovery apparatus according to the present invention, having the same structure as described above and shown in FIG. 1 . The lithium containing solution with the concentration of 90% was collected in the collecting tank 62 as described above. In addition, a pure (100%) lithium carbonate (Li 2 CO 3 ) solution was mixed with this lithium containing solution to prepare lithium carbonate (Li 2 CO 3 ) with the concentration of 95%. This reveals that according to the lithium recovery apparatus of the present invention, it is possible to achieve the higher lithium recovery rate than the conventional in this manner.
Reference Signs List
[0041] 1 supply unit
[0042] 11 storage tank
[0043] 12 filter
[0044] 2 adsorption unit
[0045] 21 column adsorption tank
[0046] 3 elution unit
[0047] 31 hydrochloric acid tank
[0048] 32 elution liquid tank
[0049] 4 cleaning unit
[0050] 41 pure water manufacturing plant
[0051] 42 pure water tank
[0052] 5 condensing unit
[0053] 51 condensing tank
[0054] 52 drain separator
[0055] 53 liquid phase tank
[0056] 54 heating section
[0057] 6 collecting unit
[0058] 61 soda ash tank
[0059] 62 collecting tank
[0060] 63 filter
[0061] 7 hydrochloric acid recycling unit
[0062] 71 condenser
[0063] 72 cooling section | The apparatus for recovering Lithium comprises: a supply unit ( 1 ) in which lithium-containing water is passed through a filter membrane to yield lithium solution; an adsorption unit ( 2 ) in which said solution adsorb the lithium in a column; an elution unit ( 3 ) by which hydrochloric acid elute the lithium in the column, yielding a lithium elute containing hydrochloric acid and lithium chloride; a cleaning unit ( 4 ) by which the column is washing; a condensing unit ( 5 ) in which the lithium elute is circularly vaporized, and the vapor is condensed to yield concentrated lithium chloride solution; a collecting unit ( 6 ) in which sodium carbonate is added to lithium chloride solution to collect the lithium as concentrated lithium solution; and a hydrochloric acid recycling unit ( 7 ) in which the residue from lithium chloride solution is cooled to yield the hydrochloric acid as used in the elution unit ( 3 ). | 8 |
BACKGROUND OF THE INVENTION
This invention relates to switching apparatus for low current switching, e.g. microprocessor level signals. More particularly, this invention relates to such apparatus having a detent structure which provides tactile feedback to the operator. Still more particularly, the invention pertains to improved detent apparatus wherein the tactile feedback can readily be varied during manufacture to assimilate that of power current switch apparatus.
The increasing use of computers has made multiplexing attractive in many consumer applications, and as a result, a need exists for switches interfaceable with microprocessor level signals. An automotive passenger car provides a good example of such application, although the switching apparatus of this invention is not limited to that application. Convenience functions in passenger cars such as the adjustment of windows, seats, mirrors, etc., are controlled by multiple switches ganged within a single package commonly located in the arm rest of a door. Such switches are designed to switch power directly to the actuators such as motors and solenoids for these items and require large, heavy cable harnesses to pass through the passenger door hinge area to be routed throughout the chassis and into other doors.
The state of the art passenger car has on-board computers for the monitoring and control of several operational functions of the engine and related components. Since the computer is already on-board, it is desirable to incorporate multiplexing of the convenience function controls with the computer. However, it is preferred to maintain the heavy duty feel, i.e. size, shape and detent characteristics, of the state of the art power switches presently being used, particularly in certain regions of the car such as the door arm rest. It is also desirable to provide such switch designs which can be readily and predictably varied during manufacture as to the tactile feedback provided in operation to meet varying specifications of the automobile manufacturers. Another feature to be considered is the capability for back lighting within the switch package that can provide a common look with the styling in other regions of the car. These features must be incorporated in a package that does not increase the footprint, i.e. the square inch surface area, and in many cases the depth and/or volume over present switches and that may be assembled at a competitive cost with present power switches which have been refined over a long time for mass production at low cost.
SUMMARY OF THE INVENTION
This invention provides low current switching apparatus having a detent for providing a tactilely discernible reduction-in-force feel to the operator, which detent can be readily and predictably changed during manufacture to provide greater or lesser force versus displacement reaction upon operation. The switching apparatus of this invention may comprise a single switch or a plurality of switches arranged in a unitary housing, assembled by stacking components in a layered manner. The switch contacts comprise spaced conductive elements of a printed circuit or the like which are bridged by a block of conductive rubber compressed thereagainst into a current conducting relationship upon switch operation. The detent structure comprises a modular block having opposed angular slots for firmly receiving the ends of one or more flat beam leaf springs to fixedly position the spring(s) in a bowed shape over a hole in an intermediate portion of the block. A separate detent support plate is provided with locating means for positioning a plurality of such modular detent blocks over respective switch contacts and in corresponding alignment with switch actuating means mounted in the cover of the unit. The force versus displacement characteristics may be predictably changed by providing alternative detent block and spring combinations wherein the parameters of spring material, thickness per beam, width, length, number of beams, clamp angle of the ends of the spring(s) and the initial arc height of the springs vary. By readily substituting the detent block assembly during assembly of the switch, more or less tactile feedback may be provided. Another parameter that can vary the tactile feedback is the travel path of the portion of the actuator that bears upon the spring. A light pipe member constitutes still another layer disposed between the interior of the cover and the detent support plate, the light pipe also functioning as a bearing support member, if necessary, for switch actuators. These and other features and advantages of this invention will become more readily apparent when reading the following description and appended claims in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a plan view of a multiple switch low current switching apparatus constructed in accordance with this invention;
FIG. 2 is a cross sectional view taken substantially along the line 2--2 in FIG. 1;
FIG. 3 is a bottom view of the cover and switch actuators of the apparatus shown in FIG. 1;
FIG. 4 is an exploded isometric view of components of the switching apparatus of this invention which are assembled in a layered arrangement;
FIG. 5 is a cross sectional view through one switching element taken along the line 5--5 in FIG. 1 and drawn to an enlarged scale;
FIGS. 6, 7 and 8 are semi-schematic views of the switch, detent and a portion of the actuator as viewed in FIG. 5, but drawn to a still greater scale, sequentially depicting actuation of the switch;
FIG. 9 is a side elevation view of an alternate detent block assembly incorporating a plurality of flat beam leaf springs stacked upon each other;
FIG. 10 is a side elevation view of another alternate detent block assembly similar to FIG. 9 incorporating stub springs stacked at each end of a full beam spring;
FIG. 11 is a force versus displacement graph for the operator of the switching apparatus of this invention;
FIG. 12 is a schematic view of the beam spring and end supports of this invention illustrating certain parameters utilized in the construction of the detent assembly thereof; and
FIG. 13 is a flow chart diagram representing the process for designing and changing the detent assembly to produce different tactile feedback characteristics thereof.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
By way of example, the low current switching apparatus of this invention is described in a convenience package switch embodiment for use in a passenger car door arm rest or the like, although it is to be understood that such switching apparatus may be used in other low current switching applications. With particular reference to FIGS. 1-3 and 5 of the drawings, a convenience switch package 2 comprises a molded insulating cover 4 to which actuator/operator assemblies for five switches 6-14 are pivotally attached. Switch 6 is a two-position lockout switch which, when the switch package 2 is used as a window control, may be operated to prevent local operation of remote door windows. The particular detent structure for the two-position switch 6 is different from the detent structure to be described in conjunction with this invention, and therefore switch 6 is not described in detail herein. The switches 8-14 are identical and therefore only switch 14 will be described in detail.
Referring particularly to FIGS. 3 and 5, an actuator 16 having trunnions 18 is pivotally supported in semicylindrical bearing journals 20 formed on the interior of cover 4, the journals 20 being open to the bottom. Actuator 16 has a peg 16a projecting through an opening 4a in cover 4. A rocker button 22 has a hollow stem 22a which is pressed onto peg 16a to assemble button 22 to actuator 16. As seen in FIG. 2, the lower lateral edges of rocker button 22 rest upon a crowned formation 4b on cover 4 for rocking movement thereon in conjunction with pivoting of the actuator 16 within the journal 20. Actuator 16 has a hole 16b extending therethrough transversely to the axis of trunnions 18 through which a leaf spring 24 may extend as seen in FIG. 3 and in dot-dash line in FIG. 5. Spring 24 functions to maintain actuator 16 in its center position. As will be noted hereinafter, the detent structure of this invention functions to bias actuator 16 to the center position and therefore spring 24 is not necessary. Actuator 16 also comprises a pair of fingers 16c and 16d extending in opposite directions from the axis of trunnions 18 and from opposite lateral sides of the actuator as seen in FIG. 3. As thus far described, the cover and actuator/operator assemblies represent a state of the art structure used in higher current switches which switch power directly to the window motors.
The switching apparatus of this invention is particularly designed to switch microprocessor level signals. The contacts for the respective switches comprise spaced conductive elements of a printed circuit which are bridged by pressing a conductive elastomer block thereagainst. Referring particularly to FIG. 4, the switch components for all five switches of convenience switch package 2 are provided on common elements which constitute a layered assembly of the switch of this invention. A molded insulating base 26 provides a support layer. A printed circuit is embodied in a planar switch 28 which rests upon a flat upper surface of base 26. The printed circuit is formed on a flexible substrate such as a Mylar sheet 30 and is covered by an insulator film 32 which may be a discrete element or applied directly to the printed circuit and Mylar sheet. Insulator 32 is provided with a plurality of openings 32a, 32b arranged in pairs aligned with the respective switches 8-14 and a single opening 32c at the left-hand end as seen in FIG. 4, which is in alignment with switch 6. Each of the openings 32a, 32b and 32c expose spaced conductive elements of the printed circuit which comprise stationary contacts of the respective switches. Planar switch 28 has a flexible ribbon conductor 28a extending therefrom having a multiple pin connector 28b attached at the end thereof.
Bridging contact elements of the switching apparatus of this invention comprise a conductive elastomer block disposed over the conductive switch contact elements on planar switch 28 and compressed thereagainst to effect current conduction. The conductive elastomer comprises a polymer or rubber material which incorporates a high concentration of filamentary conductive material into the otherwise electrical insulating material. The electrical properties of these materials are usually defined in terms of volume and surface resistivity. Such properties rely on the meshwork of conductive material and the pressure applied thereon. The conductive bridging contact may be formed as a molded sheet of rubber or polymer 34 which has a plurality of pairs of bosses 34a and 34b aligned with the switch contacts defined by the respective openings 32a, 32b of the planar switch 28. The entire sheet 34 may be made of conductive rubber or polymer or it may be made of an electrically insulating rubber or polymer coated at the undersurface of the bosses 34a and 34b with the aforementioned conductive rubber or polymer. Alternatively, any conductive material could be bonded to the undersurface of bosses 34a and 34b. Still another alternative is to provide individual blocks of conductive rubber or polymer positioned over the respective switch contacts. A single boss 34c is formed at the left-hand end as viewed in FIG. 4 and is aligned with the contacts defined by opening 32c on the planar switch.
A molded plastic detent support plate 36 is disposed on the elastomer sheet 34. Support plate 36 is provided with a plurality of pairs of offset rectangular apertures 36a, 36b into which the respective bosses 34a, 34b of elastomer sheet 34 project. The left-hand end of support plate 36 has a hole 36c into which boss 34c projects. The opposite ends of rectangular apertures 36a, 36b are provided with recessed shelves 36d which combine with the rectangular outline of the respective aperture to locate modular detent blocks 38 therein. The detent blocks 38, only one of which is shown in FIG. 4, are molded of insulating material and have a rectangular outline complementary to the shape of apertures 36a, 36b and are positioned therein with the opposite ends resting on the shelves 36d. The block 38 is provided with a depending central portion 38a which is disposed between the shelves 36d within the respective apertures. It is also provided with a hole 38b which extends upward through the center of the block to surround the respective boss 34a, 34b of elastomer sheet 34. The upper surface of the intermediate portion of detent block 38 is recessed to provide a pair of opposed upstanding surfaces which have slots 38c formed therein. The slots 38c are formed at opposite angles which converge over the intermediate portions of the detent block to define an obtuse angle therebetween. A flat beam leaf spring 40 is assembled to the detent block 38 in a bowed condition by sliding the opposite ends of the spring 40 into the respective slots 38c. The relative dimensions of the slot and spring thickness are preferably selected to permit the spring to be slid into the slot from the side to minimize stress in the spring at the entry point while maintaining a firm fit between these members. Each of the apertures 36a, 36b receives a detent block 38 and leaf spring 40 assembly therein. As will be discussed hereinafter, the angle of the slots 38c, the distance between the ends of those slots, and the length, thickness, width, material and number of springs are parameters which may be varied as well as the path of the operator/actuator to produce individual detent block assemblies which provide different tactile feedback qualities to the operator.
The multi-layer assembly comprising base 26, planar switch 28 having insulator 32 integral therewith, conductive rubber sheet 34, detent support plate 36 and the respective assemblies comprising detent blocks 38 and springs 40, is snapped into place within cover 4 by tabs 26a on base 26 which snap into rectangular holes 4c (FIG. 2) in cover 4. Base 26 is provided with a peripheral step 26b which engages a complementary shoulder 4d (FIG. 3) within cover 4 to positively locate base 26 to the cover 4. When so assembled, fingers 16c and 16d bear upon the leaf springs 40 of the respective detent blocks 38, the leaf springs supplying an initial bias of the actuator 16 to its center position and holding the trunnions 18 within the journals 20. Support plate 36 is also provided with four upstanding bearing posts 36e which align with the journals 20 in the peripheral wall of cover 4 to close off the open side of the respective journals 20. The heights of posts 36e may be closely dimensionally controlled with respect to the depth of shelves 36 d for precisely positioning the detent blocks 38 and springs 40 with respect to the actuator 16. Moreover, the engagement of actuator fingers 16c and 16d with springs 40 holds the detent block assemblies firmly in place within the respective apertures in support plate 36.
It will be noted in FIG. 4 that no upstanding posts similar to 36e are provided in the center portion of support plate 36 to cooperate with the respective journals 20 at the center of cover 4. This area is intentionally left open to permit the switching apparatus to be appropriately back lit where desired. As will be described in greater detail hereinafter, a light pipe 42 or a bearing block 44 are trapped between the interior of the cover 4 and support plate 36. Light pipe 42 is provided with a rectangular recess 42a and bearing block 44 is provided with a rectangular recess 44a in their respective upper surfaces adjacent the cover 4 to overlie the respective center journals 20, thereby closing off the open sides of the journals.
Convenience switch packages such as the package 2 of this invention, particularly when utilized in a passenger car, are preferably illuminated to indicate the function or location of the respective switches. It is preferable that the illumination be in the form of back lighting which can be readily matched to the instrumentation lighting scheme within the respective vehicle. To this end, the switch apparatus of this invention provides windows such as 4e and 4f in cover 4 and a molded transparent light pipe 42 having transverse bars 42b and 42c (FIGS. 2 and 3) aligned with the windows 4e and 4f, respectively. Indicia bearing films 46 and 48 are positioned between the cover and the cross bars 42b, 42c to be visible in the respective windows 4e and 4f. The central body of light pipe 42, which extends longitudinally between switches 8 and 10, has a hole 42d formed therein for receiving a lamp or LED 50 to provide illumination to the light pipe. The lamp 50 is provided on a microprocessor board 52 which will be described hereinafter and projects upwardly through hole 26c in base 26, hole 28c in planar switch 28, hole 34a in conductive rubber sheet 34 and hole 36e in detent support plate 36, all of which are aligned with hole 42d in light pipe 42. The opposite ends of the light pipe are provided with V-shaped notches 42e and 42f to reflect light rays within the central body of the light pipe outwardly along transverse bars 42b and 42c, respectively. The lower surfaces of the transverse bars are provided with serrations for evenly dispersed diffraction of the light within the respective transverse bars.
When illumination is desired at the right-hand side of switches 12 and 14, the light pipe 42 may be made to extend along the full length of the cover 4. However, in the embodiment illustrated, illumination at the right-hand side of switches 12 and 14 is not required and therefore a bearing block 44 is secured between the interior surface of cover 4 and support plate 6 solely for the purpose of closing off the open bottom of journals 20 and providing a bottom bearing surface for the trunnions 18 of actuators 16 associated with switches 12 and 14.
As seen in FIG. 2, the sides and one end wall of cover 4 extend downwardly beyond the base 26 to provide a skirt area for mounting and protecting the microprocessor board 52. Referring to FIGS. 2 and 4, the microprocessor board has a plurality of components affixed on both the upper and lower surfaces, the lower surface having a microprocessor 54, various chips for functions such as sensors, relay drivers and power supply protection and filtering, multi-pin connectors such as 60 and 62, and the like affixed thereto while the upper surface has various resistors and capacitors surface mounted thereon. The lamp 50 has its leads connected in the circuitry of the microprocessor board and projects upwardly therefrom to extend through the aforementioned aligned holes into the light pipe 42. Board 52 has a plurality of lateral tabs 52a which extend into corresponding holes 4g in the side walls of cover 4 to secure the microprocessor board 52 in place. The connection between planar switch 28 and microprocessor board 52 is made through the ribbon conductor 28a which extends between the side wall of cover 4 and base 26 and microprocessor board 52 out the bottom of the switch assembly and is then rolled upwardly and plugged into the multi-pin connector 62 on board 52. It should be recognized that the printed circuit of planar switch 28 could be applied directly to the upper surface of base 26 and the circuitry and components of microprocessor board 52 could be incorporated directly on the lower surface of base 26, connecting the switching printed circuit to the microprocessor printed circuit directly by vias or plated through holes when the same can be justified by economy of scale.
Referring next to FIGS. 5-8, the conductive rubber block in the form of boss 34a shown in FIG. 5, is offset upwardly from the bottom surface of rubber sheet 34 to provide a small space over conductive elements 28d and 28e forming the switch contacts. Boss 34a extends upwardly through hole 38b in detent block 38 which is disposed within aperture 36a of detent support plate 36. The slots 38c fix the opposite ends of leaf spring 40 at a predetermined angle such that it spans the intermediate recessed portion of block 38, the spring being bowed upwardly, spaced from the conductive rubber block 34a a predetermined amount. Finger 16c of actuator 16 bears upon the upper surface of spring 40 substantially at the crest of its bowed area, but somewhat offset from the true center. Similarly, finger 16d bears upon the upper surface of the spring 40 of detent block 38 which is disposed within aperture 36b located in the background as viewed in FIG. 5. Inasmuch as the switches 8-14 are double pole, double throw switches, springs 40 bias actuator 16 to its center position and the centering springs 24 may be omitted.
As the actuator 16 is pivoted from its center position shown in FIG. 5 to a second position such as clockwise as shown in FIGS. 6 and 7, the tip of finger 16c translates arcuately downward and to the left along the upper surface of spring 40 to deflect the intermediate portion of that spring from an upwardly bowed, convex condition to a reversed, downwardly bowed, concave condition as can be seen to be starting in FIG. 6 and is shown successively in FIGS. 7 and 8. The spring 40 is driven into engagement with the upper surface of boss 34a (FIG. 7) and thereafter compresses the boss 34a against the stationary contact elements 28d, 28, (FIG. 8), establishing bridging current conduction (switching) therebetween. As indicated previously, spring 40 applies a return bias to actuator 16, resisting the movement of actuator 16 from the center position (FIG. 5) to the clockwise second position (FIG. 8). This movement is also opposed by the rubber boss 34a after it is engaged by finger 16c through spring 40. The force of spring 40 resisting this movement increases throughout approximately the first half of travel of operator button 22 and changes to a decreasing force at a point in the actuator travel preceding, but substantially concurrent with, the establishment of current conduction (switching) between contact elements 28d and 28e. The resistive force applied to the operator 22 through actuator 16 by spring 40 and rubber boss 34a is depicted at curve 64 in the force versus displacement graph shown in FIG. 11. As can be seen, the changeover point B from an increasing force to a decreasing force occurs at approximately 1.5 millimeters in operator/actuator travel. The point at which current conduction is established between elements 28d and 28e (switching point) is a band S at between 1.7 and 1.9 millimeters in travel. It is desirable to have the force changeover point B slightly precede or be concurrent with the switching point so that the operator can sense actuation of the window.
The use of an elastomer as a switch making and breaking element contacted by the actuator also provides cushioning and sound deadening for the switching apparatus. No audible clicks occur from the mechanism as a result of the spring 40 changing from a convex to concave condition or the actuator finger 16c sliding along the surface of the spring 40. The resiliency of boss 34a creates little or no sound as spring 40 abuts the upper surface, and as the boss engages the contacts 28d and 28e. The travel of actuator 16 is positively limited by abutment of the right-hand end of rocker button 22 with cover 4, at which time the external force on the button increases steeply as shown at T on the curve. The slope of this portion of the curve can be made to be a more gentle slope by decreasing the stiffness of the rubber. If the rubber boss 34a is sufficiently stiff, for example, it can arrest actuator movement before the rocker button 22 strikes cover 4, eliminating noise of such impact.
A major advantage of this invention is the ability to readily redesign the detent block 38 and/or spring 40 to obtain a desired force versus displacement curve, therefor satisfying changing specifications. Using standard beam analysis such as in Marks Engineering Handbook-Mechanical Engineering sections or following the Bernoulli-Euler Law and assuming thin beam approximation, i.e. the length of the beam remains constant throughout its movement, simple design relationships can be derived to relate a change in geometric parameter to a desired affect on the force versus displacement curve. With reference to FIG. 12, the following parameters are utilized in the beam design:
______________________________________material (Young's modulus)l = length (length along beam between supports)d = distance (between supports)w = width (dimension into paper)t = thickness (of the individual beam)h = height (initial arc height)θ1,θ2 = clamp angles (beam ends)n = number of beamsp = actuator travel path (arcuate, normal, cammed)______________________________________
Also considered in the overall design of the detent structure are certain parameters of the rubber block, e.g. boss 34a, that is compressed on the conductive segments 28d, 28e to effect switching. The Young's modulus of the rubber, Poisson's ratio, pressure required to achieve current conduction between the conductive segments 28d, 28e, the dimensions of the block, its location with respect to spring 40 and the constraints that position it above the conductive segments 28d, 28e, are each such parameter.
With reference to FIGS. 11 and 13, the design is determined with an elastic analysis software program such as ANSYS (trademark of Swanson Analysis Systems, Inc.), a self-contained general purpose finite element analysis program. Due to the simplicity of the configuration, it is recognized that simpler software tools can be developed specifically dedicated to this task, but such development is not dealt with herein. The design is initiated by defining a target force versus displacement curve F/D such as 64 using the specifications, switching point S and tolerances provided by the customer. The materials of the rubber (block 34a) and the beam (spring 40) are selected. The rubber is measured to determine its Young's modulus and the force necessary to effect switching. Parameters of the rubber, namely, the aforementioned dimensions and location, are inputted to the elastic analysis program. The location of the upper surface of the rubber block is defined by the earliest allowable closure (switching) point in the travel. The dimensions of the rubber block are selected from Young's modulus, the force required to effect closure (switching), the latest allowable closure point in the travel, and the desired rubber restoring force that combines to the overall F/D curve. Also inputted to this program are the beam parameters defined above in conjunction with the defined F/D curve. Certain of the beam parameters are given. Using scaling equations developed from simple beam spring theory, reasonable choices to one skilled in the art are selected for the unknown or unestablished parameters. The program produces outputs that are compared to the F/D curve for compliance with the permitted tolerances. If not, it cycles to a redesign mode for changes in selected parameters. Another output of the analysis program compares the maximum stress of the beam to the working stress known from the selected material to determine that the maximum stress is less than the working stress. If not, the program cycles to the redesign mode.
If yes answers are obtained from both output comparisons, a physical model of the switch and detent structure are fabricated. The physical model is tested and compared to the F/D curve, and if it does not meet the tolerances of the curve, redesign is required. If it does fall within the F/D curve, it is then checked to determine that switching point S is within the tolerances. If these tolerances are not met, the dimensions and/or location of the rubber block are re-analyzed, changes selected and new parameters of the rubber block are again fed into the program. When yes answers are obtained to both of the latter comparisons, the switch and detent structure are subjected to cycle life tests to finalize the design.
When the basic design is established, new designs to meet different F/D curves can be readily accomplished by variations in one or a few of the parameters. As mentioned hereinabove, the Bernoulli-Euler Law which states that
E·I·Curvature = Σ moments
at all points along the beam where
E=Young's modulus
I=Area moment of inertia about the neutral axis of the beam ##EQU1## Scaling laws general to any beam clamped in some manner can be developed from the foregoing, and used in practical design tradeoffs.
Assume, for example, an initial design has been developed and some change is required to increase the force. In general, a force is specified by the customer in terms of specific travel. This is equivalent to specifying a stiffness (force÷travel). The scaling laws for beams of uniform width and thickness are: ##EQU2## where: E=Young's modulus
W=beam width
n=number of beams
t=beam thickness
l=beam length ##EQU3## As an example, if it is desired to reduce stress and increase force for the same amount of travel and same beam material, then ##EQU4## Substituting (6) into (5): ##EQU5## resulting in ##EQU6## This method trades-off either the width w, length l or number of beams n to achieve desired results. In the resulting equation above, thickness was eliminated from the initial solution. Therefore, thickness must subsequently be calculated from the formula. Alternately, length could have been eliminated to calculate thickness t in which case l would need to be subsequently calculated from the equation: ##EQU7## Thus, the thickness t of the spring 40 may be changed, the length l may be changed giving rise to an increased height h of the arc, etc. As seen in FIG. 9, one or more additional spring 40' may be used, with the thickness of the slots 38c' correspondingly increased. To avoid an inventory of blocks having different thickness slots 38c', the slots can be standardized to accommodate the multiple thickness and shims such as stub springs 40" (FIG. 10).
The low current switching apparatus described hereinabove provides the size, shape and feel of state of the art power current switching devices for similar applications, but switches signals at microprocessor levels to enable the switch to be used in a multiplexing application, thereby providing the OEM customer the advantages of multiplexing. The modular detent enables the tactile feedback of the switch to be changed readily and quickly during manufacture, to satisfy varying requirements. The switching apparatus incorporates a layered assembly concept for economic advantage in assembly, including a light pipe layer where specified. Although the switch has been shown in a preferred embodiment, it is to be understood that it is susceptible of various modifications without departing from the scope of the appended claims. | Pivotal movement of a switch actuator drives a finger projecting from the actuator against a convexly bowed leaf spring, depressing an intermediate portion of the leaf spring to an unstable concave condition. The leaf spring resists the actuator movement, initially with an increasing force but changing to a decreasing force at a predictable point in actuator movement to provide tactile feedback at an operator affixed to the actuator. The leaf spring is a flat beam. The spring foce and point of changeover can be readily and predictably varied during manufacture by selecting springs having different widths, thicknesses or other variable parameters. A modular block holds the spring in the bowed condition and is positioned relative to the actuator finger by a support plate. The actuator finger drives the spring against a conductive rubber block, compressing the block against spaced conductors on a printed circuit to complete the circuit. A plurality of such switches are made in a common package by layering a printed circuit, insulator sheet, conductive rubber sheet with raised bosses, detent support plate and a plurality of detent blocks with bowed springs, between a base and a cover. Back lit illumination is provided by a light pipe trapped against the cover as an additional layer. A microprocessor board, connected to the internal printed circuit, is attached to the switch housing exteriorly of the base. | 7 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a manufacturing method and apparatus of a fiber reinforced composite member, in which a plurality of products can simultaneously be manufactured.
2. Description of the Related Art
In order to raise the performance of a rocket engine using NTO/N 2 H 4 , NTO/MMH, and the like as impelling agents, heat-resistant temperature of a combustor (thrust chamber) is requested to be raised. For this purpose, a coated niobium alloy having a heat-resistant temperature of about 1500° C. has heretofore been used as a chamber material for many rocket engines. However, this material is disadvantageously heavy because of its high density, low in high-temperature strength, and has a short coating life.
On the other hand, since ceramic is high in heat resisting properties but disadvantageously brittle, a ceramic matrix composite member (hereinafter abbreviated as CMC) has been developed by reinforcing the ceramic with ceramic fiber. Specifically, a ceramic matrix composite member (CMC) comprises ceramic fiber and ceramic matrix. Additionally, in general the CMC is indicated as ceramic fiber/ceramic matrix by its material (e.g., when both are formed of SiC, SiC/SiC is indicated). Additionally, the ceramic matrix composite member (CMC) will be described hereinafter in detail, but the present invention is not limited to this, and can similarly be applied also to carbon-based composite members such as C/C, C/SiC and SiC/C.
Since CMC is light-weight and high in high-temperature strength, it is a remarkably prospective material for the combustor (thrust chamber) of the rocket engine, further a fuel piping in a high-temperature section, a turbine vane of a jet engine, a combustor, an after-burner component, and the like.
However, the conventional CMC cannot hold its hermetic properties and is disadvantageously low in resistance to thermal shock. Specifically, for the conventional CMC, after a predetermined shape is formed of ceramic fibers, a matrix is formed in a gap between the fibers in so-called chemical vapor infiltration (CVI) treatment. However, a problem is that it takes an impractically long time (e.g., one year or more) to completely fill the gap between the fibers by the CVI. Moreover, in a high-temperature test or the like of the conventional CMC formed as described above, when a severe thermal shock (e.g., temperature difference of 900° C. or more) acts, the strength is drastically lowered, and the CMC can hardly be reused.
Therefore, the conventional ceramic matrix composite member (CMC) cannot substantially be used in the combustor (thrust chamber), the fuel piping or another component requiring the hermetic properties and resistance to thermal shock.
In order to solve the aforementioned problem, the present inventor et al. have created and filed a patent application, “Ceramic-based Composite Member and its Manufacturing Method” (Japanese Patent Application No. 19416/1999, not laid yet). The Ceramic-based Composite Member can largely enhance the hermetic properties and thermal shock resistance and it can be for practical use in the thrust chamber, and the like. In the invention, as schematically shown in FIG. 1, after subjecting the surface of a shaped fabric to CVI treatment to form an SiC matrix layer, PIP treatment is performed to infiltrate and calcine a gap of the matrix layer with an organic silicon polymer as a base.
In a manufacture process shown in FIG. 1, from a braiding process ( 1 ) to a CVI process ( 3 ), a jig or mandrel, for example, of carbon or the like is used to form a fabric 1 in a periphery and subsequently, the CVI treatment is performed. Since matrix is formed in the gap of the fabric 1 by the CVI treatment and a shape is held, in this stage, the mandrel is detached, and subsequent PIP treatment ( 4 ) and machining ( 5 ) are performed in a conventional art. Additionally, in the braiding process, as schematically shown in FIG. 2, for example, braid weave is used in which a braided thread is alternately and obliquely woven into a middle thread.
In the manufacture process, however, products (hereinafter referred to as CMC product) of the ceramic matrix composite member have heretofore been manufactured individually one by one. In this case, particularly, in the braiding process, when fiber is wound onto the mandrel, the fiber is wound onto an engaging allowance to a textile weaving loom and a portion of the mandrel other than a product portion. Therefore, as compared with the fiber used in the product portion, there are a large proportion of finally wasted fiber, much fiber loss, and the like, and this raises cost. For example, although ceramic fiber used in the CMC product is expensive, in the conventional art, even with a relatively large CMC product (thrust chamber or the like), a fiber effective utilization ratio is only around 20%, and about 80% results in loss.
Moreover, even in the braiding process and the subsequent CVI treatment, PIP treatment and machining, the products are individually treated one by one in the conventional art. Therefore, particularly in the small-sized CMC product, there is a problem that much labor is required for setting/preparation or the like to the apparatus and that productivity is low.
SUMMARY OF THE INVENTION
The present invention has been developed to solve the problem. Specifically, an object of the present invention is to provide a manufacturing method and apparatus of a fiber reinforced composite member, which can simultaneously manufacture a plurality of products, remarkably reduce fiber loss, and enhance productivity.
According to the present invention, there is provided a manufacturing method of a fiber reinforced composite member comprising steps of: connecting a plurality of mandrels to one another to constitute an integral mandrel; forming a fabric on the surface of the integral mandrel; and infiltrating the formed fabric with matrix.
In addition according to the present invention, there is provided a manufacture apparatus of a fiber reinforced composite member for forming a fabric on the surface of a mandrel, and infiltrating the formed fabric with matrix, and the manufacture apparatus comprises a connection segment for connecting a plurality of mandrels to one another.
According to the method and apparatus of the present invention, since the integral mandrel obtained by connecting the plurality of mandrels to one another is used to manufacture a ceramic matrix composite member, a plurality of products can simultaneously be manufactured on the surface of the plurality of mandrels.
Moreover, for fiber loss generated in a braiding process for winding onto an engaging allowance to a loom and a portion of the mandrel other than a product portion, even when the integral mandrel is used, an absolute amount is substantially the same as that when unit products are individually manufactured one by one. Therefore, by performing simultaneous braiding for a plurality of products, the fiber loss per unit product can be reduced to a few fractions.
Furthermore, even in the braiding process and subsequent CVI treatment, PIP treatment and machining, simultaneous machining is possible for a plurality of products, labor of setting/preparation or the like to the apparatus is reduced to a few fractions per unit product as compared with a case in which the products are individually treated one by one, and the productivity can be enhanced so much more.
Additionally, according to a preferred embodiment of the present invention, after infiltration of the matrix, a fiber reinforced composite member is cut at a connected portion at which a plurality of mandrels are connected to one another.
By this method, the member can be divided into respective unit products, and subsequently necessary processes are further performed so that the products can be completed.
Moreover, a maximum diameter of a connection segment is formed to be smaller than a diameter of the connected portion to the mandrel.
In this constitution, since a stepped portion is hardly formed in the connected portion of a mandrel segment, the fiber can smoothly be wound around the entire surface of an integral mandrel in the braiding process, and the fabric can be formed on the surface of each mandrel segment.
Moreover, after the CVI treatment and PIP treatment, if treatment of each product is necessary, by separating the connected portion of the mandrel segment, separation into the respective products can easily be performed.
Furthermore, the mandrel is constituted to be dividable at a middle portion which is smaller than both end portions.
By this constitution, by dividing the mandrel segment at the middle portion which is smaller than each end portion, the mandrel can be separated/removed without damaging the product.
Other objects and advantageous characteristics of the present invention will be apparent from the following description with reference to accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic view of a CMC manufacturing method to which the present invention is applied.
FIG. 2 is a schematic view of a braid weave.
FIG. 3 is a schematic view of a mandrel applied to a manufacture apparatus of the present invention.
FIGS. 4A to 4 D are schematic views of the manufacturing method in which the mandrel of FIG. 3 is used.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
A preferred embodiment will be described hereinafter with reference to the drawings.
FIG. 3 is a schematic view of a mandrel applied to a manufacture apparatus of the present invention. As shown in FIG. 3, a mandrel 10 is an integral mandrel constituted by connecting both end portions 12 a , 12 b of a mandrel segment 12 for a unit product to one another, and linearly connecting a plurality of (three in FIG. 3) mandrel segments to one another.
Moreover, connection segments 14 a , 14 b are connected to both end portions 12 a , 12 b of the mandrel segment 12 via screws or the like, and the same end portions of the mandrel segment 12 (e.g., 12 a and 12 a , or 12 b and 12 b ) are detachably connected to each other. Additionally, the connection segments 14 a , 14 b may be used to form the mandrel 10 as the integral mandrel of four or more mandrel segments 12 .
Furthermore, the mandrel segment 12 is constituted to be dividable at a middle portion 12 c which is smaller than both end portions 12 a , 12 b . Additionally, when this middle portion is particularly small, by disposing a groove in a circumferential shape, the mandrel may be constituted to be ruptured and divided along the groove.
Moreover, as shown in FIG. 3, a maximum diameter of the connection segment 14 a , 14 b is formed to be smaller than a diameter of a connected portion of the mandrel segment. Therefore, a groove 15 with a diameter smaller than that of a product is constituted between adjacent mandrel segments 12 .
FIGS. 4A to 4 D are schematic views of a manufacturing method in which the mandrel of FIG. 3 is used. In the drawing, FIG. 4A is a view of a braiding process to a machining process, FIG. 4B is a view of a dividing process for each product, FIG. 4C is a divided view of the connection segment, and FIG. 4D is a divided view of the mandrel segment.
As shown in FIG. 4A, after forming a fabric 1 on the surface of the integral mandrel 10 , the formed fabric 1 is infiltrated with matrix. If necessary, further machining of an outer peripheral surface is performed on the integral mandrel 10 as it is. Thereby, a plurality of products can simultaneously be manufactured on the surface of a plurality of mandrel segments 12 .
Additionally, in the method of the present invention, since the same end portions of both end portions 12 a , 12 b of the mandrel segment 12 are connected to each other, a stepped portion can hardly be formed in the connected portion. Therefore, in the braiding process the fiber can smoothly be wound onto the entire surface of the integral mandrel 10 , and the fabric 1 can be formed on the surface of the respective mandrel segments 12 .
Moreover, for fiber loss generated in the braiding process for winding onto an engaging allowance to a loom and a portion of the mandrel other than a product portion, even when the integral mandrel 10 is used, an absolute amount is substantially the same as that when unit products are individually manufactured one by one. Therefore, by performing simultaneous braiding for a plurality of products, the fiber loss per unit product can be reduced to a few fractions.
Furthermore, even in the braiding process and subsequent CVI treatment, PIP treatment and machining, simultaneous machining is possible for a plurality of products, labor of setting/preparation or the like to the apparatus is reduced to a few fractions per unit product as compared with a case in which the products are individually treated one by one, and the productivity can be enhanced so much more.
Moreover, as shown in FIG. 4B, thereafter, at a portion of the groove 15 for product separation, for example, a cutter 16 is used to perform cutting and dividing into respective products (ceramic matrix composite members 2 ). Subsequently, as shown in FIG. 4C, the connected portion of the mandrel segment 12 is separated, so that respective products can be separated.
Furthermore, as shown in FIG. 4D, by dividing the mandrel segment 12 into respective end portions 12 a , 12 b at the middle portion 12 c , the segment is divided into the respective unit products (ceramic matrix composite members 2 ), and is subsequently subjected to further necessary processes (e.g., PIP treatment and machining), so that the products can be completed.
Moreover, the dividing process of each product of FIG. 4B is preferably performed after the PIP treatment and machining are completed, but the present invention is not limited to this, and the process may be performed after performing the CVI treatment to such an extent that a product shape can be held.
As described above, according to the manufacturing method and apparatus of the present invention, a plurality of products can simultaneously be manufactured, this remarkably reduces the fiber loss, the productivity can be enhanced, and other superior effects are provided. The method and apparatus are effective particularly for a small-sized (outlet diameter of 10 mm or less) chamber or nozzle.
Additionally, the present invention is not limited to the aforementioned embodiment, and can of course be modified variously without departing from the scope of the present invention. For example, in the above description, a thrust chamber or another rotary member as the product has been described in detail, but the present invention is not limited to this, and can also be applied to an arbitrary-shape fuel piping, turbine vane, combustor, afterburner component, and the like. | There is presented a method of connecting a plurality of mandrels to one another to constitute an integral mandrel 10, forming a fabric 1 on the surface of the integral mandrel, and infiltrating the formed fabric with matrix. A plurality of products can simultaneously be manufactured, and this can remarkably reduce fiber loss and enhance productivity. | 1 |
RELATED APPLICATIONS
[0001] This application is a conversion of U.S. Provisional Application Serial No. 60/279,837, filed Mar. 29, 2001, the disclosure of which is incorporated herein for all purposes.
TECHNICAL FIELD
[0002] The invention relates to a method and apparatus for cleaning and inspecting underground pipes and conduits in order to facilitate repair and replacement of such under ground pipes.
BACKGROUND OF THE INVENTION
[0003] A known technique for replacing sanitary sewer lines and various other underground conduits and pipes is to burst or expand the existing pipe and then pull a replacement pipe through the expanded bore. In one variation of this process, a horizontal directional drill advances a drill string with pipe bursting or splitting tool affixed to the end of the drill string. The system may include a impact device mounted at the end of the drill string such as a rotary impactor (see U.S. Pat. No. 5,782,311) or a pneumatic impact tool that delivers cyclic impacts to the bursting or splitting tool. The replacement pipe is attached to the bursting or splitting tool and pulled through the bore behind it.
[0004] It is common practice to clean an existing sanitary sewer pipe prior to a line replacement operation. Lateral connections, for example to residences, must be accurately located and marked to avoid excessive excavation. However, in many cases, existing underground pipelines will have an accumulated buildup of solids, grease, and wax-like materials that may interfere with the inspection, bursting, splitting and/or replacement operations. The accumulated buildup may also prevent or interfere with locating pipe joints, which in the case of cast iron pipes may require particular attention during the splitting operation.
[0005] In the past, sanitary sewers have been cleaned with specialized equipment including high pressure water jets operating at 2000 psi. This method of cleaning requires the use of a jet truck, i.e., a truck specially equipped with one or more specialized pumps designed to deliver moderate volumes of water at extremely high pressures, a high pressure hose to reach the area or areas to be cleaned, and nozzles specially designed to direct the high pressure water into a jet capable of cutting the materials. The nozzles are radially spaced and angled rearwardly so that the discharge of water through the nozzles creates a reaction force to propel the high pressure hose through the pipe being cleaned. A “soup” of suspended solids, grease and water flows downstream through the pipeline. In some cases the jet truck will vacuum this soup from a manhole, the same manhole the spray head was introduced from.
[0006] This invention makes opportunistic use of the presence of a horizontal drilling machine using a rigid drill string during a pipe bursting and replacement operation. Conventionally, horizontal directional boring machines are used only for the pipe bursting and replacement stage of the operation. The present invention provides accessories by which other useful steps can be carried out using the directional boring machine, including cleaning and inspecting existing pipes.
SUMMARY OF THE INVENTION
[0007] The invention provides a method of replacing an existing underground pipe, especially a sanitary sewer line, using a boring machine that advances a drill string of hollow rods through the existing pipe. Such a method includes the steps of:
[0008] (a) mounting a rotary cleaning tool on a distal end of the drill string;
[0009] (b) moving the cleaning tool progressively through the underground pipe while rotating the drill string in order to clean the inside of the pipe;
[0010] (c) flushing debris loosened by the cleaning tool from the pipe using a pressure fluid;
[0011] (d) removing the cleaning tool from the drill string and mounting a camera assembly on the distal end of the drill string;
[0012] (e) moving the camera and drill string through the underground pipe on the drill string and inspecting the inside surface of the pipe with the camera;
[0013] (f) removing the camera from the drill string and replacing it with a pipe destroying apparatus;
[0014] (g) moving the pipe destroying apparatus through the pipe to destroy the existing pipe; and
[0015] (h) installing a replacement pipe along the same line as the destroyed existing pipe. The existing pipe can be destroyed by any known method appropriate to the material the pipe is made from, such as pipe bursting or pipe slitting and spreading. According to preferred forms of the invention, the pressure fluid is supplied through the drill string and ejected from the cleaning tool as the cleaning tool advances through the existing pipe.
[0016] The existing pipe is typically a sanitary sewer line having a number of lateral line connections. As such, step (e) preferably involves determining the locations of the lateral line connections to the existing pipe, such as by connecting a sonde to the camera and marking the position of the lateral above ground by detecting the sonde's position when the camera shows a lateral connection. For this purpose, the camera is typically a video camera that provides a live feed of the pipe interior and has a built in light source.
[0017] According to a preferred form of the invention, steps (a) to (c) are performed as the drill string is extended from an entrance to an exit at opposite ends of the existing pipe. The entrance and exit may be openings in a pit or manhole. Step (d) is then performed while the distal end of the drill string is near the exit, and step (e) is performed as the drill string is retracted from the exit back to the entrance. In this manner the existing pipe is cleaned, flushed and then inspected in one down and back cycle of the drilling machine. The same drilling machine is then used for the subsequent steps of destroying the existing pipe, replacing it with a new pipe, and optionally de-beading the new pipe after lateral connections have been welded on.
[0018] The pipe inspection and cleaning aspects of the invention can also be used separately when the occasion requires and specialized equipment is not available. A method for inspecting an inside surface of a pipe using a horizontal boring machine that advances a drill string of hollow rods through the pipe includes the steps of attaching a camera to a distal end of the drill string, moving the camera through the underground pipe on the drill string, and imaging the inside surface of the pipe with the camera while the camera is inside the pipe. A method of cleaning an underground pipe includes the steps of mounting a rotary cleaning tool on a distal end of the drill string, moving the cleaning tool progressively through the underground pipe while rotating the drill string in order to clean the inside of the pipe, and flushing debris loosened by the cleaning tool from the pipe using a pressure fluid.
[0019] The invention further provides a pipe cleaning tool useful in such a method adapted to be mounted on the end of a drill string and advanced through an underground pipe with a horizontal drilling machine to clean the pipe. Such a tool includes a generally cylindrical body including a front nose section, a plurality of side flats at intervals around the circumference of the body, and a rear connecting portion configured for connecting the pipe cleaning tool to the drill string. A flexible flap mounted on each of the flats extends tangentially from the body and is configured to scrape along the inside of the pipe as the cleaning tool is advanced through the pipe. The body further includes fluid passages for communicating through the drill string with a source of a pressure fluid, and a plurality of nozzles connected to the fluid passages for ejecting the pressurized fluid in a radial direction as the tool is advanced through the pipe.
[0020] The invention also provides an apparatus for inspecting a pipe. Such a device includes an electronic camera and an elongated carrier body having a recess adapted to receive the camera therein, an end connecting portion configured for mounting the carrier body on a drill string, and an opening whereby the camera can be positioned to capture an image through the opening. The camera is preferably a video camera and transmits its signal through a cable to a video display above, permitting the operator to inspect the condition of the line interior and locate lateral branch lines. These and other aspects of the invention are described in the detailed description that follows.
BRIEF DESCRIPTION OF THE DRAWINGS
[0021] [0021]FIG. 1 is an illustration of a pipe cleaning operation wherein a pipe section between two manholes is being cleaned in a method according to the invention;
[0022] [0022]FIG. 2 is a first side view of a cleaning tool according to the invention;
[0023] [0023]FIG. 3 is a second side view of the cleaning tool of FIG. 2;
[0024] [0024]FIG. 4 is sectional view taken along line A-A of FIG. 3;
[0025] [0025]FIGS. 5 and 6 are front and rear views, respectively, of the cleaning tool of FIG. 2;
[0026] [0026]FIG. 7 is a perspective view of a camera assembly according to one aspect of the invention, the camera assembly being mounted on a sonde housing; and
[0027] [0027]FIG. 8 is a partial lengthwise section of the camera assembly of FIG. 7.
DETAILED DESCRIPTION
[0028] [0028]FIG. 1 illustrates a pipe inspection operation wherein a pipe section 12 extending between first and second manholes 14 and 16 is to be cleaned and inspected. In the operation, an operator, using a conventional directional boring machine 10 , drills an entry bore 18 from the surface on an arcuate path, intersecting existing pipe 20 with a drill string 22 in a tangent manner, preferably at an existing exposed location such as at a first manhole 14 . Alternately, instead of boring in an arcuate path, directional boring machine 10 may be placed in an access pit excavated adjacent to the start of a pipe section 12 to be replaced. The particular tool to be used in the operation is installed on the drill string 22 in manhole 14 and the drill string is positioned inside of the existing pipe section 12 that is due for replacement.
[0029] In accordance with a method of the invention, a cleaning tool 24 is installed on the free end of the drill string 22 in manhole 14 . Using the high pressure fluid pump mounted on the horizontal direction drilling machine (hereafter HDD), pressurized cleaning fluid is supplied to the tool through drill string 22 to tool 24 which delivers a spray to the interior of the pipe section 12 to clean and wash the accumulated grease and solids from the pipe. The spray may, for example, be water plus a grease-cutting surfactant or detergent. In the embodiment illustrated in FIG. 1, tool 24 is attached to the front end of a sonde housing 21 , which in turn is mounted on drill string 22 .
[0030] Turning to FIGS. 2 through 6, cleaning tool 24 includes a generally cylindrical shaped body 26 including an annular groove 28 positioned midway along its length. Body 26 includes a forwardly rounded (semi-spherical or bullet shaped) nose section 30 ahead of groove 28 to aid in inserting and guiding tool into and through pipe section 20 . As best shown in FIGS. 4 and 6, a splined recess or socket 32 extends into body 26 at the rear of tool 24 and is configured to receive the male end of a splined connection or joint such as described in Wentworth U.S. Pat. No. 6,148,935, the contents of which are incorporated by reference herein. Alternatively, tool 24 may be connected to drill string 22 with any number of conventional joints known in the art including, for example, a standard API threaded joint.
[0031] Nose 30 has a plurality of radially spaced flats or mounting surfaces 36 . Flats 36 are located ahead of groove 28 but rearwardly spaced from tip 40 of nose 30 . A flexible cleaning paddle or flap 38 is mounted on each of flats 36 such that a forward end 44 of each flap 38 abuts a forward endwall 42 of each flat 36 . Each of flaps 38 includes a forward end 44 , a rear end 46 a leading side 48 and trailing side 50 and an angled side portion 52 between forward end 44 and a trailing side 50 . As shown, each of flaps 38 is configured to extend tangentially outward from nose section 30 so that trailing side 50 scrapes the interior of pipe 20 as tool 24 is rotated, cleaning grease and solids from the interior surface of pipe 20 . Side section 52 is angled at approximately 450 relative to forward end 44 , and rear end 46 extends past the associated flat 36 , overlying a minor portion of groove 28 . The use of angled side 52 , as opposed to joining forward end 44 and trailing side 50 at a right angle, allows flaps 38 to gradually engage grease and solids built up on the interior of pipe 20 as tool 24 is advanced, and tends to reduce the forces applied to the flap and prevent breakage. To further prevent breakage, flaps 38 are preferably formed from a hard, flexible plastic material exhibiting a high level of abrasion resistance.
[0032] As shown, three flaps 38 are mounted on flats 36 with flaps 38 spaced equiangularly (at 0°, 120° and 240°) from each other around the circumference of nose section 30 . It will be appreciated that a greater or lesser number of flats 36 and flaps 38 , spaced at different and/or non-uniform intervals may be employed. For example, a tool 24 designed for small diameter pipes may only include two flaps 38 , spaced 180° apart.
[0033] Each of flaps 38 includes one or more (two shown) countersunk apertures 54 that align with threaded bolt holes 59 for receiving a threaded fastener such as a cap screw 58 that is screwed into threaded hole 59 in body 26 to secure flaps 38 to tool 24 . As will be appreciated, mounting flap 38 on flat 36 as illustrated protects screws 58 and the portion of flap 38 through which cap screws 58 extend from abrasion as tool 24 is rotated and advanced in pipe 20 . Additionally, as illustrated, each flap 38 is mounted such that the forward end 44 of each flap 38 abuts a forward endwall 42 of flat 36 to help prevent the forward ends 44 of flaps 38 from catching on obstructions in a pipeline as tool 24 is advanced into the pipe, thereby minimizing the possibility that a flap will be torn off of tool 24 in operation.
[0034] Body 26 includes an axially extending fluid passage 60 and threaded apertures 62 that communicate with drill string 22 secured in recess 32 to allow a pressurized fluid such as water to pass through body 26 and apertures 62 to one or more nozzles 64 . In the illustrated embodiment, tool 24 is provided with three nozzles in groove 28 , each positioned midway between adjacent flaps 38 at equal intervals (60°, 180° and 240°) around the circumference of groove 28 . Nozzles 64 are positioned in recesses 65 in groove 28 to protect the nozzles from abrasion and from hanging up on obstructions during the cleaning operation.
[0035] Nozzles 64 are each directed at different angular orientations to eject the pressurized fluid evenly around the circumference of the tool and are angled rearwardly (e.g., 5 to 45°) to create a flow in a rearward direction to wash out the pipe interior as the drill string advances from through pipe 20 from an entry zone (manhole 14 ) to an exit zone (second manhole 16 ). In one embodiment wherein a Vermeer Navigators® horizontal drilling machine is employed, approximately 50 gpm of water at 150 psig. is supplied through the drill string to nozzles 64 to suspend and flush grease and solids from pipe 20 as tool 24 is advanced. Solids and grease scraped from the interior of pipe 20 are thus slurried with water or a mixture of water and a surfactant and flow back past tool 24 to manhole 14 where the mixture may be vacuumed or pumped out of the manhole if the volume of slurry warrants.
[0036] Tool 24 provides several advantages over conventional high pressure water blasting techniques for cleaning underground horizontal pipes. Tool 24 utilizes equipment, in particular the horizontal drilling machine, that is necessarily on site, eliminating the need for special high pressure water blasting equipment. Further, tool 24 is driven with a rigid drill string, the tool can be forced through accumulations of grease and solids in a pipe that a conventional water blasting apparatus may not be able to penetrate. The use of flaps 38 further provides a scraping action against the interior of a pipe being cleaned that tends to dislodge accumulated materials faster than a conventional water blasting apparatus that relies on one or more narrow streams of high pressure water to cut accumulated material from the inside of the pipe. In applications were the material to be removed is sufficiently soft, water soluble and/or of sufficiently small volume, flaps 38 may be omitted. In other applications the horizontal drilling machine may be equipped with a pump capable of delivering a water pressure sufficient to cut though the build up in which case the flaps may also be unnecessary. The flushing operation may be carried out at the same time as rotary cleaning, or thereafter.
[0037] In many cases, after the cleaning operation is completed, it is advantageous to visually inspect the interior of the pipe. One important reason for visual inspection of the pipe is to accurately determine the locations where lateral pipe runs are connected to the main pipeline. In the case of a sanitary sewer, these joints typically comprise a connection to a house or other building that must be replaced after the new pipe has been installed. Replacing such lateral connections generally requires excavating and replacing the joint to reconnect the lateral pipe run. Determining the location of the joint through a visual inspection of the interior of the pipe facilitates this process and reduces the amount of excavation required.
[0038] Conventional techniques for inspecting the interior of a horizontal underground pipe in this manner utilize a camera mounted on a powered robot or tractor equipped with a powered ground drive such as wheels or tracks or pulled with a cable. A cable is attached to the robot or tractor to transmit signals from the camera to a recording device such as a video recorder and the location of lateral connections is determined by the footage of cable extended into the pipe or through the use of a radio frequency transmitter carried by the robot. In the case where a transmitter is used, the location of the crossover is determined by locating the robot with a receiver carried on the surface when the camera transmits an image corresponding to the location of a lateral connection.
[0039] The use of a robot or tractor to carry a camera through an underground pipe for inspection purposes has disadvantages. The robot or tractor is an expensive piece of additional equipment that must be brought on site and maintained. Since a robot or tractor relies on wheels or tracks for mobility, such units are subject to becoming jammed or stuck in the pipeline, requiring excavation or similar measures to retrieve the unit.
[0040] Referring to FIGS. 7 and 8, in one aspect of the invention, a camera assembly 70 is mounted on the end of a drill string for inspecting an underground pipe, preferably after the pipe has been cleaned. As best shown in FIG. 8, camera assembly 70 includes a generally cylindrical carrier body 72 with a splined recess or socket 74 extending into the rear of carrier body 72 that is configured to receive the male end 76 of a splined connection or joint such as described in Wentworth U.S. Pat. No. 6,148,935. As shown, carrier body 72 is removably coupled to sonde housing 21 with such a joint by a retainer such as a roll pin that interlocks sonde housing 21 and body 72 . Alternatively, carrier body 72 may be connected to drill string 22 with any number of conventional joints known in the art including, for example, a standard API threaded joint. Carrier body 70 is substantially smaller in diameter than the pipe to be inspected and includes one or more forwardly inclined side surfaces 78 extending forwardly from a supporting heel 79 to aid in guiding carrier assembly 72 smoothly through the pipe to be inspected.
[0041] A video camera 80 is mounted in a central, longitudinally extending cavity 82 in carrier body 72 for inspecting the pipeline. As illustrated, camera 80 is installed in cavity 82 through a forwardly facing opening 81 in carrier body 72 and secured with a threaded collar 84 . Opening 81 provides camera 80 with a forward field of view through which camera 80 may image the walls of a pipe as it advances through the pipe. A cutout 83 is formed in a sidewall 85 of carrier body 72 to further enable camera 80 to image the wall of a pipe as the camera passes through the pipe if camera 80 is equipped for side view imaging. One such camera suitable for use in the practice of the invention is the Pearpoint model 455 TwinView Dual Sensor Auto Upright Digital color camera manufactured and sold by Pearpoint, Inc., 72055 Corporate Way, Thousand Palms, Calif. 92276. The Pearpoint Model 455 includes LED light heads and clock/counter clockwise side-view rotation capability. In the illustrated embodiment, camera 80 can provide an image from both the front and side vantage points. It may be advantageous to reposition the camera to permit other views, such as a rear view of there the drill string has been.
[0042] Signals from video camera 80 are transmitted to the operator through a camera cable 87 which passes from the rear of camera 80 through a protective conduit 86 , positioned in an axially extending slot 86 in carrier body 72 . As shown, camera cable 87 is coupled to an extension cable 88 with a cable connector 90 which allows the camera assembly to be readily connected and disconnected to cable 88 when the camera is installed and removed from the drill string. In order to protect the connector from decoupling during operations, one or more tethers 92 are connected to cable 88 with a tubular holder 94 and secured to camera carrier body 72 .
[0043] In operation, after pipe section 12 has been cleaned with tool 24 , the tool is removed and camera assembly 70 is mounted on the end of drill string 22 . Preferably, camera assembly 70 is mounted on drill string 22 so that the camera will be pulled though the bore as the drill string is retracted through pipe section 12 . Cable 88 is connected to camera cable 87 and camera assembly 70 is pulled though the bore as drill string 22 is retracted from manhole 16 to manhole 14 , allowing camera 80 to acquire and transmit images of the pipe interior to the operator on the surface, who view the camera images on a video display. This allows the operator to determine the location of lateral connections and pipe joints either by measuring the footage of cord extended. Cable 88 , which extends out in front of the camera 70 , may be marked with length gradations 91 for this purpose, in the manner of a tape measure. In the alternative, camera assembly 70 is mounted on sonde housing 21 with sonde 100 generating a signal detectible with a walkover receiver on the surface above the pipe section. Using the walkover receiver, in conjunction with the images supplied by camera 80 , an operator can quickly and easily locate lateral connections and pipe joints and mark them on the surface such as with a flag or spray paint. Similarly, depending on the conditions, it may be possible to transmit the image data with the camera forming part of a wireless network rather than use a cable to transmit the images to the surface. After the inspection is completed, the camera assembly is uncoupled from drill string 22 and disconnected from cable 88 after which cable 88 is retrieved from pipe section 12 , completing the inspection operation.
[0044] After the cleaning and/or inspection processes are completed, pipe 12 may be replaced using a number of conventional bits, reamers, pipe bursting devices and pipe pullers, by bursting or slitting the existing pipe and then pulling in the replacement pipe. The bore may be completed either at a pipe exit pit or existing exit structure beneath the ground surface such as a manhole. Lateral connections are then made by excavating at the locations found earlier and joining the laterals (branch lines) to the new pipe. If desired, in accordance with the method of the invention, the operator then reenters the new pipe with the drill string and de-beads the fuse joints of the new product pipe using a drill stem mounted on a debeading device as known within the industry. Such a device acts as a reamer to shear the beads from the inside of the pipe using a circumferential motion. If desired, the operator may then perform a final camera inspection of the installed pipe using camera assembly 70 .
[0045] While certain embodiments of the invention have been illustrated for the purposes of this disclosure, numerous changes in the method and apparatus of the invention presented herein may be made by those skilled in the art, such changes being embodied within the scope and spirit of the present invention as defined in the appended claims. The camera, for example, need not be provided with the specialized housing described, and could be pulled through the pipe connected to the end of the drill string by a tether. The terminal or distal end of the drill string, as used in the claims, means the end of the foremost of a series of identical hollow drill rods, or a starter rod, sonde housing or other component that may be interposed between the attachment of the invention and leading rod of the drill string. | A method of replacing an existing underground pipe, especially a sanitary sewer line, uses a boring machine that advances a drill string of hollow rods through the existing pipe. The method includes the steps of mounting a rotary cleaning tool on a distal end of the drill string, moving the cleaning tool progressively through the underground pipe while rotating the drill string in order to clean the inside of the pipe, flushing debris loosened by the cleaning tool from the pipe using a pressure fluid, removing the cleaning tool from the drill string and mounting a camera assembly on the distal end of the drill string, moving the camera and drill string through the underground pipe on the drill string and inspecting the inside surface of the pipe with the camera, removing the camera from the drill string and replacing it with a pipe destroying apparatus, moving the pipe destroying apparatus through the pipe to destroy the existing pipe, and then installing a replacement pipe along the same line as the destroyed existing pipe. This permits a single piece of equipment, such as a directional drill rig, to perform several different functions as part of the pipe replacement process. | 4 |
This application is a continuation of Ser. No. 417,286 filed Nov. 19, 1973, now abandoned.
SUMMARY OF THE INVENTION
The invention is an automatic cleaning or flushing system which in the exemplary embodiment is for use in reverse osmosis machines. Typically, reverse osmosis machines embody core members having a surface carrying a semipermeable membrane through which the reverse osmosis takes place for purposes of separating components from liquid. The herein invention provides a system of pumps, valving, and automatic controls to provide for automatic flushing and cleaning of all of the membranes by way of process functions as described in detail hereinater, includng relaxing of the membrane by reduction of pressure, injection of air or inert gas into the feed liquid, pumping flushing water or other liquid through the machine for purging, and/or feeding in chemical additive liquid. In the preferred exemplary form of the invention as described in detail herein, a complete automatic electrical sequencing system is provided whereby the cleaning operations or sequence is undertaken at periodic intervals in response, for example, to a time-operated switch, or other conditions which automatically indicate the need for cleaning and/or purging.
The invention may be adapted to all membrane separation systems such as electrodialysis, piezodialysis, pressure dialysis, and biomembranes.
Probably the greatest difficulty encountered in the operation of reverse osmosis machines is that of preserving membrane usefullness. In most reverse osmosis applications, after a period of operation, the membrane starts to loose its capacity. A typical installation may start off with a membrane flux density of 20 gallons/sq ft/day and, in time, the membrane could deteriorate to 8 or even 6 gallons/sq ft/day. To minimize this condition of membrane decay, a system of automatically treating the membrane at periodic intervals has been originated.
In normal operation, particulate matter in the feed water has a tendency to settle out on the surface of the membrane, and certain particles not only settle on the membrane, but fuse together to make a continuous film over the surface of the membrane. The clogging of the membrane can also be caused by concentrated salts that precipitate out of the feed solution and settle on the surface of the membrane. Even if a reduction in membrane flux could be tolerated, deposits of foreign matter on the surface of the membrane are undesirable because they tend to allow bacterial growth that will in time attack and destroy the membrane. Membrane separation systems suffer from the coating forming over the surface which is called fouling. It can be formed by precipitation of inorganic salts, settling out of flocs of saturated organic or inorganic material or coating out of inorganic materials. These are caused primarily through factors which decrease the turbulence at the interface of the process fluid with the membrane surface leading to deposits within the boundary layer. These deposits cause a reduction in solvent, i.e., water permeation through the membrane, thus providing a significant change in the quality and quantity of both the final concentrate and the permeate.
To minimize the condition described, high Reynolds numbers have been used, and the herein invention uses a plastic spring turbulator to further increase the Reynolds number adjacent to the surface of the membrane.
It is conventional in the art to inject detergents, chemical removing agents, and enzymes in an attempt to remove the foreign matter that has collected on the surface of the membrane. These methods are not completely successful. One other method is to shut the machine down and allow the normal osmotic flow through the membrane to dislodge the foreign matter on the surface of the membrane. Normal osmotic flow takes place between the permeate (that has already passed through the membrane) backwards through the membrane to the feed side of the membrane. The amount of benefit obtained from this method is argumentative at best.
The herein invention provides the reverse osmosis machine with an automatic timing device, supplemental valves, and piping to automatically treat the membrane at periodic intervals. A significant improvement obtained by this supplemental system involves the injection of air or another noncondensable gas, into the feed water. The air entrained in the feed water creates a tremendous turbulation and very effectively dislodges the foreign matter on the surface of the membrane. This air injection method works especially well when used in conjunction with the plastic spring turbulator, which is disclosed in U.S. Pat. No. 3,768,660 issued Oct. 30, 1973, owned by the common assignee and which is hereby incorporated herein by reference.
In addition to injecting air, this system permits injection of flushing solutions at periodic intervals. Air may or may not be used in conjunction with the flushing solution. Also, this system provides for relaxing of the membrane by reducing the pressure on the feed side (or both sides). As the membrane is not a rigid structure, the reduction in pressure allows the membrane to flex and dislodge foreign matter from the surface of the membrane. The membrane relaxing technique may be combined with the injection of a flushing solution, wih air injection, or with both injecting of a flushing solution and with air injection.
The herein invention provides a fully automated improved cleaning system which will realize the cleaning objects by accomplishing the following:
1. Decreasing operating pressure (surging) to allow membrane relaxation, and in some cases, osmotic backflush without affecting the process fluid quality. When a positive displacement pump is used in conjunction with an accumulator (on the discharge side of the pump), a decrease in operating pressure will result in a momentary increase in flow velocity due to the action of the accumulator. This momentary velocity increase is referred to as surging and has a beneficial effect as far as removing foreign matter from the surface of the membrane.
2. Automatically injecting flush solutions, when required, the flush cycle being timed to allow minimal loss of process fluid.
3. Injecting gas during low pressure surge. Tests have shown that this gas injection during the low pressure phase of operation effects much superior membrane cleaning than the procedures which are normally used, and will not affect the process fluid quality. The realization of this improved cleaning is a specific object.
4. Combination of all of the above can be undertaken by the system, optionally as desired, and in a fully automated sequence.
The herein system includes a series or system of fully automatic controls which allow sequencing of all or part of the auto flush pressure surge process as described. This control sequencing system is adjustable to accommodate all phases of the operation automatically without an operator, and may be altered to accommodate variations in quality of the feed solution. It will sequence the various phases so they can be accomplished individually or sequentially, via cascaded control circuitry.
All components to realize this auto flush pressure surge cleaning are integrated into the system of the invention, minimizing user's labor, both on installation and operation, and thus reducing his costs and promoting economy, these ends being among the objects realized by the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
Further objects and additional advantages of the invention will become apparent from the following detailed description and annexed drawings, wherein:
FIG. 1A is a diagrammatic view of a simplified, exemplary form of the flushing system. This figure shows diagrammatically one module and header of a reverse osmosis machine;
FIGS. 1B, 1C, 1D, and 1E are partial views illustrating different types of automatic control instruments which can be used to initiate the flushing cycle;
FIG. 2 is a diagrammatic isometric view illustrating a portion of a complete reverse osmosis machine to illustrate flows, feed into the modules, flows of concentrates out, and flows of permeate out;
FIG. 3 is a diagrammatic or schematic view of the automatic flushing system illustrating complete automatic control circuitry and instrumentalities for effecting the automatic flushing cycle;
FIGS. 3A, 3B, and 3C are partial views similar to FIGS. 1B through 1E, illustrating different control instruments; and
FIG. 4 is a chart illustrating an exemplary flushing sequence as effected by the timer operated cam switches and control circuitry of FIG. 3.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 shows a reverse osmosis machine arrangement. The small circles on FIG. 1 represent entrained air. As this air is constantly expanding, it is readily evident that a high velocity of air and feed water scrub the surface of the membrane. The construction shown is that of application Ser. No. 225,945 filed Feb. 14, 1972, now U.S. Pat. No. 3,786,925, owned by the common assignee and which is hereby incorporated herein by reference.
FIG. 1 shows a sectional view of a part of the reverse osmosis machine as illustrated schematically in FIG. 2, showing a part of tube sheet 10 and a header 17. Tube sheet 10 has secured in it the ends of tubes 12 and 14 which are sections of similar U-tubes 16. Numeral 17 designates a metal header casting which connects tube sections 12 and 14. Header 17 has mounting lugs which can be attached to tube sheet 10 by suitable means. It has two integral, cylindrical parts 24 and 26 which have extending bosses or nipples 28 and 30 having bores 32 and 34 and counterbores 31 and 33 as may be seen. These bores receive cylindrical parts of plastic fittings forming part of the desalination cells. Within parts 24 and 26 are bores 19 and 21 connected by passageway or port 23. Bores 19 and 21 ae bevelled at their ends as shown and sealed to tube sheet 10 by O-rings 25 and 27.
The headers like 17 connect U-tubes like 16 in successive tiers at different levels as may be seen in FIG. 2 and as described in detail in the application referred to.
Numeral 18 designates an inlet header casing and 18' designates a similar casting which is an outlet header. Inlet header 18 is shown in detail in the prior application.
Within tube 12 of U section 16 is shown a cylindrical desalination cell 36 having a plastic end fitting 38 which is described in detail in said U.S. Pat. No. 3,768,660. Numeral 39 designates a plastic helical spring, the convolutions of which under the influence of pressure, can move axially to clean the membrane in conjunction with the air bubble turbulence 41.
As explained and shown in FIG. 2, there are a plurality of U-tubes 16 connected to headers 17 mounted from tube sheet 10 with a reverse osmosis cell in each tube section with a continuous series flow of feed fluid through the tubes as illustrated in FIGS. 1 and 2.
End parts 42 of fittings 38 which extend from the headers connect to permeate manifold 44 as may be seen in FIG. 2. Manifold 44 has four series of equally angularly spaced nipples 46, these series of nipples being connected to the ends parts or nipples 42 of the reverse osmosis cells. The purified fluid is drawn off through this manifold. The feed of fluid to be purified or desalinized, in the case of desalination cells, conncts to inlet header 18 as designated by the arrow. The concentrate is taken off at outlet header 18' as indicated.
FIG. 1A shows feed pump P which pumps into header 17 as shown from feed line L1. The flushing liquid line is designated L2 having in it solenoid valve SV2 and check valve CV1 connected to line L1. The chemical additive line is designated L3, having in it solenoid valve SV1.
FIG. 1A shows the reverse osmosis system equipped with a solenoid valve SV4 which bypasses the back pressure regulator valve BPR. Solenoid valve SV4, when opened, drops the pressure in the membrane module and allows the membrane to relax. Normally, back pressure regulator BPR maintains the pressure in the unit. When the solenoid valve opens, by passing the flow around the back pressure regulator, the surface of the membrane is exposed to a sudden increase in velocity and also a sudden decrease in pressure. These are the factors that tend to dislodge the foreign particles on the surface of the membrane. Solenoid valve SV2 is used to inject a flushing solution into the feed water. A valve SV3 may be provided to allow compessed air to enter the feed water stream as in FIG. 3. Depending upon the type of membrane used, the feed solution, and other operating conditions of the system, it may be desirable to preserve membrane usefulness by only membrane relaxation at any predetermined period, by the injection of air or a specific type of noncondensable gas at predetermined intervals, or a combination of any two or three of the above methods as referred to more in detail hereinafter.
The herein process has been tested on various solutions with a high degree of success. The flushing or cleaning cycle may be triggered by a reduction in permeate flow, an increase in concentration or the permeate, and an increase in feed pressure and similar factors.
FIG. 1A shows a simplified control circuit for the flushing system. The letter T designates a timer motor which can be energized by manual push button switch PB. It drives switch mechanism S having three contact terminals and three blades which control the solenoid valves SV1, SV2, and SV4. The solenoids in each case are designated by the letter E. Back pressure regulator BPR controls the pressure in the reverse osmosis unit, that is, on the concentrate side which effectively controls the pressure on the inlet side. The operating pressure might be in a range from 300 psi to 1500 psi. Solenoid valve SV4 bypasses back pressure control valve BPR when the solenoid valve is opened. Pressure in the reverse osmosis machine is dropped, allowing the membrane to relax.
FIGS. 1B, 1C, 1D, 1E, and 1F illustrate optional alternatives or instrumentalities which may be used individually or collectively along with or without manual switch PB. FIG. 1B illustrates a 24-hour time switch TR. FIG. 1C illustrates a flow switch FS response to flow of permeate. It would start a flushing cycle in response to reduction of flow of permeate. FIG. 1D illustrates a conductivity probe CP which would operate in response to conductivity of the permeate illutrative of the degree of purity. FIG. 1E illustrates a differential pressure switch DP which would operate in response to pressure conditions indicative of fouling or clogging in the reverse osmosis machine.
OPERATION
From the foregoing, those skilled in the art will readily understand the operation of the systems illustrated by FIGS. 1A, 1B, 1C, 1D, and 1E. Normally, feed is pumped by pump P through line L1 to the reverse osmosis machine, and the concentrate is taken off through line L4 and the permeate, through lines L5 and L6 as described. If there is need for a flushing or cleaning cycle, it may be initiated manually or in response to any of the instrumentalities as illustrated in FIGS. 1B, 1C, 1D, and 1E. The flushing cycle is initiated by closure of any one or more of the contacts of the manual push button PB or the switches of FIGS. 1B-1E. Opening of solenoid valve SV4 bypasses back pressure regulator BPR, dropping the pressure and relaxing the pressure on the membrane to effect. the cleaning function in this manner, as described in the foregoing. Opening of solenoid SV2 allows flushing liquid to be pumped through the machine for purging by pump P, line L1 being closed off at this time by a solenoid valve (not shown). This flows through check valve CV1. Opening of solenoid valve SV1 allows suitable chemical additive which may be of a soap type to be drawn into the inlet line to the pump and circulated through the reverse osmosis machine.
FIG. 3 is a diagrammatic view of an exemplary system similar to that of FIG. 1A with a preferred exemplary form of control system more fully illustrated.
In FIG. 3, the reverse osmosis machine is illustrated at RO. The feed line is designated at L1 to feed pump P. The feed line to the pump has in it solenoid valve SV1. Numeral L2 designates the line for flush liquid and L3 the line for chemical additive which connects to line L2. Check valve CV1 is in the discharge line from additive pump P1. In flush water line L2 is solenoid valve SV2.
The air admission line is designated at L3 having in it check valve CV2 and solenoid valve SV3.
The concentrate line from the RO unit is designated at L4 having in it back pressure regulator BPR. There is a bypass line around this unit having in it solenoid valve SV4.
FIG. 3 shows the injection of air between the pump and the RO cell. Under certain conditions, it is desirable to inject the air or other noncondensable gases at the inlet of the pump instead of at the outlet of the pump. It is possible also to construct a system that has no pump and the feed pressure is supplied by the city water pressure. On a system of this type, the air is injected anywhere along the feed piping.
In installations with relatively low air pressure, an alternative piping arrangement to permit air injection by substantially lowering the manifold pressure consists basically of a bypass about the entire RO cell system and back pressure regulating valve. Shown in FIG. 3 is a additional solenoid valve SV5. Valve SV5 serves as a liquid bypass between the feed and concentrate system of the membrane module. Electrically, valve SV5 is in paarallel with BPR bypass valve SV4. In the bypass mode, SV5 allows a portion of the feed stream to be bypassed around the membrane module, reducing the flow rate through the membrane module.
Reduced liquid flow rate allows for a further reduction in the differential pressure across the membrane module caused by hydraulic head losses. The reduced feed pressure (bypass mode) allows for the injection of gas at pressures less than normal shop air.
The control circuitry for the system including the automatic sequencing mechanism will next be described. The letter E adjacent to the solenoid valves designates the electrical solenoid associated with each valve.
The power line terminals ae designated L1, L2, and L3. These terminals ae on a magnetic starter MS having a winding interlock contact IC and terminals M1, M2, and M3. Letters F1 and F2 designate fuses. Numeral T designates an automatic timer assembly driving cam operated single pole, double throw switches operated by the cams designated S1, S2, S3, S4, S5, and S6. The switches have common terminals and normally opened and normally closed contacts as designated.
Numerals T1 and T2 designate step-down transformers, each having a primary winding and a secondary winding. Character S7 designates a manual control switch having two pairs of bridgable contacts, one pair for manual start and one for automatic control as will be described.
Numeral T3 designates a further step-down transformer having a primary winding and a secondary winding, the primary winding being connected to terminals M1 and M2 of magnetic starter MS and having its secondary winding connected to hour meter HM. The letters PS designate a pressure switch having high pressure and low pressure contacts as indicated, which may operate at 1500 and 300 psi in the exemplary embodiment.
The letter C designates an electric clock switch having a winding C1 and automatic time-operated switch contacts C2. Letters MF designate a manual switch for manually starting the flushing sequence. The leads to this switch may be bridged by way of leads XX which may connect to alternate optional types of controls as shown in FIGS. 3A, 3B, and 3C as previously described.
Referring to the electrical circuitry, it will be observed that terminals M1, M2, and M3 connect to the motor driving feed pump P. The power is carried from the terminals L1 and L2 to the primary of transformers T1 and to the primary of T2 by way of manual switch S7.
The secondary of transformer T1 supplies power under control of the cam switches, the pressure switches, and clock switch C2 for the solenoid valves. The secondary of transformer T2 supplies power for winding C1 of clock C.
Cam switch S1, through its NO contact, controls the motor of the timer assembly T. Cam switch S2 controls solenoid valve SV1 through its NO contact and solenoid valve SV2 through its NC contact. Cam switch S3 controls solenoid valves SV4 and SV5; cam switch S4 controls solenoid valve SV3; and cam switch S5 controls chemical additive pump P1. Pressure switch PS normally controls power through winding W of the magnetic starter MS. The low pressure contacts of pressure switch PS can be shunted by the NO contact of cam switch S6 as will be described.
Character TS1 designates a terminal strip to which there is a return lead as indicated from each electrical component.
Normal Operation of the Reverse Osmosis Machine -- FIG. 3
FIG. 3 shows in detail an exemplary form of automatic control system. The following describes the normal operation of the reverse osmosis machine, after which the automatic sequencing operation of the flushing system will be described.
In the normal operation, switch S7 is closed, that is, both of its contacts are closed. This is a manual switch, which when manually operated, first closes the automatic contacts and then closes the manual contacts which remain closed. Closure of the S7 contacts energizes the magnetic starter MS. Upon energization, it closes its contacts in the three wire power line and also closes the interlock contact IC, the purpose of which will be described presently.
Power is now supplied to transformers T1 and T2. Actually, power is always on the transformer T2. The secondary supplies power to the motor winding of the clock switching mechanism C. This clock mechanism operates continuously even when the machine is shut down.
Pressure switch PS operates between the exemplary pressure figures of 1,500 psi for the high pressure contact and 300 psi for the low pressure contact. At time of starting, the low pressure contact is open because the pressure has not had an opportunity to build up. At this time, the operator sets the back pressure regulator BPR to the pressure he wishes to maintain in the reverse osmosis unit. Accordingly, the pressure begins to rise until the low pressure switch LP closes. When it closes, it produces an additional circuit through interlock contact IC of the magnetic starter which shunts the manual contact switch S7. The machine will now remain in operation even though these contacts may be opened, and the manual contacts of switch S7 will now be opened. Should pressure in the unit now rise high enough to open the HP contacts of pressure switch PS, this would shut down the machine by de-energizing the magnetic starter MS. It will be observed that if the high pressure switch opens and shuts down the machine, causing the magnetic starter to release, it will open the interlock contact IC. The machine cannot now be restarted unless the manual contacts of switch S7 are again closed.
Flushing Sequence Operation -- FIG. 3
The flushing sequence may be started by the 24-hour clock C or by the manual start switch MF or optionally, by any one of the switches illustrated in FIGS. 3A, 3B, or 3C which are or may be in parallel with manual switch MF and the 24-hour clock switch. The flow switch, FIG. 3A, would close in response to a condition indicating the need for cleaning which would be a reduction in flow of permeate. The differential pressure switch, FIG. 3B would indicate a need for cleaning which would be a particular pressure differential. The conductivity monitor switch, FIG. 3C, would close in response to a monitored condition, indicating reduction of quality of the permeate indicative of a need for cleaning.
Closure of the 24-hour clock switch energizes the timer T. Cam switch S1 closes its normally open contact establishing a circuit, keeping the timer in operation. Power is supplied by the secondary of transformer T1.
In the exemplary embodiment, the sequence is as follows:
1. Start cycle.
2. Bypass (or shunt) pressure switch.
3. Switch feed.
4. Dump concentrate and start the additive flowing.
5. Shut off additive.
6. Switch feed.
7. Close concentrate bypass.
8. Enable pressure switch.
FIG. 4 is a chart of an exemplary flushing cycle illustrating cam switch initiated functions and exemplary times for each phase of the cycle.
Operation of switch S1 to close its NO contact is a first step in the sequence; cam switch S6 closes to a normally open contact which bypasses the LP contact of the pressure switch. This is necessary to keep the machine operating, since the LP contact is closed at this time, but it will open further on in the sequence as will be described and has to be bypassed or shunted at this time.
The next step in the sequence is that cam switch S2 will open a normally closed contact and close a normally open contact which causes valve SV1 to close and solenoid valve SV2 to open. The operation cuts off feed to pump P and admits flush water to the pump. A period of time will be required for the flush water to circulate through the reverse osmosis machine and to flush out impurities, this being a purging period which in the exemplary form of the invention might be a minute and a half to three minutes as illustrated. There is now a buffer zone of clear flush water between the pump inlet and concentrate line. Now, the chemical additive pump will be turned on as follows. Cam switches S4 and S5 will now close to a normally open contact completing enabling circuits to be energized hereafter to chemical pump P1, to valve SV which is in the air injection line. Cam switch S3 at this time has its contact open and shortly after the actuation of cam switches S4 and S5 closes its normally open contact providing power from the positive side of the secondary of transformer T1 to cam switches S4 and S5; and it now energizes the chemical pump P1 and the solenoid valve SV3. Closure of the normally open contact of cam switch S3 also provides power to the solenoid valves SV4 and SV5 which bypass the back pressure regulator BPR with the result that it closes. Cam switch S3 provides a power interlock which makes it possible for cams S4 and S5 to operate separate switches, whereby it is possible to open the circuits of these switches as different times, as will be described more in detail presently.
In the exemplary embodiment, the chemical additive pump is kept on for about two minutes although this period is variable from about 1-121/2 minutes. In the exemplary embodiment, after two minutes, cam switch S5 de-energizes the chemical additive pump. This discontinues the supply of chemical additive (soap) to the reverse osmosis unit. The actual cleaning solution which is used depends on the application to which the system is being put, that is, the type of liquid that is being cleaned by reverse osmosis. Thus, the cleaning solution might be ordinary bleach, sodium hypoclorite, or iodine. In the exemplary embodiment, now for a period which may be period for 9 minutes, the flush water is being pumped through the system, purging the cleaning solution and the water mixture. The air injection remains on while purging. At the end of the 9 minute period, the air injection valve SV3 is shut off, and the feed streams are switched, cutting off the flush water, closing SV2 and re-opening feed valve SV1 as follows. Cam switch S4 now opens its normally closed contact to close SV3 and to cut off the air. Cam switch S2 opens a contact, de-energizing solenoid SV2 and cutting of the flush water and closes a contact re-energizing solenoid valve SV1 establishing normal feed to feed pump P. At this time, solenoid valve SV4 is still open. Thus, there is no pressure in the reverse osmosis unit. The feed stream is now allowed to feed for a minute and a half in the exemplary embodiment to flush the purge water out of the system. At the end of this period, cam switch S3 operates to de-energize SV4, causing it to close, allowing pressure to build up in the system and causing back pressure regulator BPR to come back into operation. Cam switch S3 also opens its contact which had been closed, interrupting the power circuit to cam switches S4 and S5, although these contacts had already opened. At this time, the circuit shunting or bypassing the LP contact of the pressure switch PS is still closed and in the exemplary embodiment, it will remain closed for about 30 seconds, at which time, cam switch S6 operates to open a contact, interrupting this shunt or bypass circuit which has been kept closed up to this time to permit the system to return to normal operation.
From the foregoing, those skilled in the art will readily understand the invention and the manner in which all objects are achieved.
The foregoing disclosure is representative of preferred forms and adaptations of the invention and is to be interpreted in an illustrative rather than a limiting sense, the invention to be accorded the full scope of the claims appended hereto. | An automatic flushing and cleaning system for membrane separation machines such as reverse osmosis machines having plural modules or membranes. Cleaning may be by way of reducing the pressure to allow the membrane to relax, by the injection of air or inert gas to provide turbulence, and/or by injection of flushing liquid which may include chemical cleaning additives. Pumps, automatic valving, and pressure controls are provided, along with a complete timer operated electrical sequencing system whereby desired purging, flushing and cleaning cycles are automatically undertaken at periodic intervals or in response to one or more preferred conditions. | 1 |
RELATED APPLICATIONS
The present application is a continuation-in-part of pending application Ser. No. 13/199,910 filed on Sep. 12, 2011.
FIELD OF THE INVENTION
The present invention relates to an apparatus and method for accelerating food product in order to cause the product to be stretched aligning the fibers of the product.
BACKGROUND OF THE INVENTION
Current forming technology relies on high pressure, speed and complicated material flow pathways which produce a product lacking in quality. High pressure works the meat cells, the higher the pressure the more massaging or squeezing of the meat cells takes place. High speed combined with a complicated flow path massages and works the meat product, releasing myosin/actin from the cells causing the muscle fiber to bind together and contract (protein bind). The contraction takes place during high heat application as in cooking. The action of the meat fiber is to contract in length, this contraction combined with protein bind not only shortens the muscle fiber which if not controlled causes odd cook shapes but a rubber like texture with a tough bite.
In muscle, actin is the major component of thin filaments, which together with the motor protein myosin (which forms thick filaments), are arranged into actomyosin myofibrils. These fibrils comprise the mechanism of muscle contraction. Using the hydrolysis of ATP for energy, myosin heads undergo a cycle during which they attach to thin filaments, exerting a tension, and then depending on the load, perform a power stroke that causes the thin filaments to slide past, shortening the muscle.
Muscle fibril structure is measured from micrometers to several millimeters in length. These fibril structures are bundled together to form muscles. Myofibril proteins are the largest group and probably more is known about these proteins than any other. In muscle cells actin is the scaffold on which myosin proteins generate force to support muscle contraction. Myosin is the major protein that is extracted from the muscle cells by mechanical means.
An important purpose of tumbling and massaging is to solubiliize and extract myofibril proteins to produce a protein exudate on the surface of the meat. The exudates bind the formed pieces together upon heating. Binding strength also increases with increased massaging or blending time. This is due to increased exudate formation on the surface of the meat. Crude myosin extraction is increased with increased blending time.
Grinding/chopping utilizes the concept of rupturing the cell to release protein. This mechanical chopping or shearing takes place at the shear/fill plate hole. This process extracts actin and myosin from muscle cells.
Mixing, utilizes friction and kinetic energy to release protein extraction. Fill hole shape and spacing can cause dead spots and turbulence in the meat flow. This change of direction is a form of mixing and massaging. This is another process, which extracts actin and myosin from muscle cells.
Massaging takes place almost anywhere meat comes in contact with processing equipment and is moved or has a change of direction via pressure. This is also a procedure which involves extracting actin and myosin from muscle cells.
SUMMARY OF THE INVENTION
It is an object of the present invention for the fiber orientation technology to reduce the release and mixing of myosin with actin. It is an object of the present invention for the fiber orientation technology to control orientation of the fiber. It is an object of the present invention for the fiber orientation technology to provide less myosin activity resulting in a better bite/bind and control over the final cook shape.
The present invention relates to an apparatus and method for accelerating food product in order to cause the product to be stretched aligning the fibers of the product. It is an object of the present invention for a hole or orifice to change size from a larger to a smaller diameter with vertical or concave sides having a sharp edge. The principle has design similarities to a venturi. It is referred to as a choke plate, nozzle, venturi, orifice, or a restriction to flow which results in product acceleration with a corresponding pressure drop through the orifice.
By reducing the cross-sectional area of a tube through which a substance passes, the velocity is increased. This is the principle of Conservation of Mass. When the velocity increases the pressure of the material is reduced. This is the principle of the Conservation of Energy.
For every liquid, there is a ratio between the cross-sectional area (C) and the cross-sectional area (c) through which velocity can only be increased by reducing temperature or increasing pressure. Although ground meat is not a homogeneous liquid, the same concepts still apply. It is impossible to attain choked flow unless there is a transition between the orifices and the small orifice has a finite length.
A venturi allows a smooth transition from a larger orifice to a smaller one. This transition minimizes flow transitions and thereby reduces restrictions in the system. The transmission minimizes energy loss and supports fiber alignment.
The transition in a venturi is extremely difficult to create in a production tooling environment. As a result, using the geometric properties of a sphere or similar shape allows the ability to obtain many of the venturi effect properties using standard production practices.
All points on a sphere are the same distance from a fixed point. Contours and plane sections of spheres are circles. Spheres have the same width and girth. Spheres have maximum volume with minimum surface area. All of the above properties allow meat to flow with minimum interruptions. There are not static or dead zones. No matter what angle the cylinder intersects the sphere, the cross section is always a perfect circle.
It is an object of the present invention to increase meat velocity forcing linear fiber alignment.
It is an object of the present invention to have spherical geometry or a similar shape in fill or stripper plate to create venturi effects.
It is an object of the present invention for the process to make a patty cool uniformly and soften the texture/bite of the product.
The present invention relates to a food patty molding machine having a mold plate and at least one mold cavity therein. A mold plate drive is connected to the mold plate for driving the mold plate along a given path, and a repetitive cycle, between a fill position and a discharge position. A food pump is provided for pumping a moldable food product through a fill passage connecting the food pump to the mold cavity when the mold plate is in the fill position. A fill plate, interposed in the fill passage adjacent to the mold plate has a multiplicity of fill orifices distributed in a predetermined pattern throughout an area aligned with the mold cavity when the mold plate is in fill position. It is an object of the present invention for the fill orifices to define paths through the fill plate, wherein some of the paths each have a path portion obliquely angled or perpendicular to the fill side of the mold plate. It is an object of the present invention for the paths to comprise spherical intersections or a curved structure. It is an object of the present invention for the side of the fill plate which is in contact with the stripper plate to comprise a spherical hemisphere or curved structure which has a diameter between approximately 1.1 to 2.5 times greater than a cylindrical portion which intersect the top of the mold plate perpendicularly or at an angle of less than or equal to about +/−75 degrees, or about +/−45 degrees in a preferred embodiment as measured from vertical in the longitudinal direction of the mold plate. By a reduction in the diameter a “choked-flow” condition is created. By using spherical sections or a curved structure, intersections between cylinder and spheres or curved structures create transitions which can be manufactured whose geometry approaches a venturi style system. It is preferred to have a sharper edge from the edge to the hole. It is an object of the present invention to make the edge sharper with a grinder. It is an object of the present invention for the fill plate to be chrome coated on the side adjacent to the stripper plate with a material significantly harder than the fill plate material. This is because the stripper plate wears out. The piece is approximately 39 Rockwell C. It becomes approximately 60-65 Rockwell C. It is an object of the present invention for the material to be applied in a thickness to facilitate a surface which cuts the food product upon movement of a stripper plate. The material goes from 1/1000 th of an inch to 10/1000 th of an inch with the chrome. A cutting hemisphere into bottom of plate, with a cylinder.
It is an object of the present invention for the stripper plate to be interposed in the fill passage immediately adjacent to the fill plate. It is an object of the present invention for the stripper plate to be movable in a direction transverse to the mold plate, between the fill and discharge locations. It is an object of the present invention for the stripper plate to have a multiplicity of fill openings aligned one-for-one with the fill orifices in the fill plate when the stripper plate is in fill position. It is an object of the present invention for the stripper plate drive to be synchronized with the mold plate drive, such that the movement of the stripper plate facilitates the cutting of the meat product, which was pushed through the fill plate by the food pump. It is an object of the present invention for the stripper plate drive to move the stripper plate to its discharge position, in each mold cycle, before the mold plate moves appreciably toward the discharge location. It is an object of the present invention for the stripper plate drive to maintain the stripper plate in the discharge position until the mold plate cavity is displaced beyond the fill orifices.
It is an object of the present invention for the fill paths to be in a direction to the front or rear of the machine. It is an object of the present invention for all fill paths to consist of a hemispherical shape which is intersected by a cylindrical shape at an angle less or equal to about +/−75 degrees of vertical, and preferably about +/−45 degrees of vertical.
It is an object of the present invention to use spherical geometry, with cylindrical intersections, and the ratio of the diameter of the sphere divided by the area of the cylinder be approximately 1.1 to 2.5 to create conditions to meat flow which maintain improved cell structure.
Irregular shapes do not have diameters, but they do have areas. For a given ratio of a linear item, the ratio becomes the square of the linear ratio. For curved and irregular shapes, the ratio of the initial area and the reduced area is from approximately 1.2 to 6.25.
This air flow can be accelerated by using a system which will reduce the cylinder size. Using the equation from Bernoulli's law of A 1 V 1 =A 2 V 2 , the velocity is increased by reducing the cross sectional area.
The typical way of accomplishing this is the use of a venturi nozzle. However, a venturi requires a gradual area reduction and a finite length throat. Given the restrictions of the plate thickness in the breathing area, it is not feasible to put a venturi in a breather plate.
However, utilizing the properties of a sphere, the air can achieve acceleration by intersecting a cylinder with a sphere of a larger diameter.
In a sphere pressure is equal in all directions. Therefore, when the sphere is intersected by a cylinder, the air will move in a direction coaxial with the cylinder at a high velocity. The impact on the meat particles in the breather system is greater because air moving at a higher velocity will generate more momentum.
It is an object of the present invention to provide a venturi effect in the hole by creating a sphere to cylinder hole. This creates a venturi effect or a venturi pump. This accelerates the product through the hole. It is an object of the present invention for this to be used in a fill plate.
BRIEF DESCRIPTION OF DRAWINGS
FIG. 1 is an unassembled view of a fill plate and stripper plate of the present invention.
FIG. 2 is an assembled view of a fill plate and stripper plate of the present invention.
FIG. 3 shows a side view of an embodiment of the invention.
FIG. 4 shows a top view of an embodiment of the invention.
FIG. 5 is an illustration of a venturi design of the prior art.
DETAILED DESCRIPTION
FIG. 1 shows an unassembled view of a fill plate 10 , stripper plate 12 and a top plate 14 .
FIG. 2 shows an assembled view of the fill plate 10 , stripper plate 12 and top plate 14 , further comprising a stripper plate spacer and hold down 16 , a cylindrical section 18 and a curved section 20 .
FIG. 3 shows a side view of the patty molding machine having an auger driver motor 30 an auger 32 , knockouts 34 and a shear plate drive cylinder 36 .
FIG. 4 shows a top view of an embodiment of the present invention, having a stripper plate drive 40 , a fill and stripper plate assembly 42 , a mold plate 44 and a draw bar 46 .
FIG. 5 shows a venturi 100 comprising a diameter 102 , angle transition 104 , throat length 106 and discharge 108 .
The present invention relates to fiber orientation technology. The fiber orientation technology drops pressure across the fill plate, aligns the fibers of meat so that the contraction of the muscle fiber that does take place is in a direction of choice controlling both bite and shrinkage. The fiber orientation technology provides a lower resistance to product flow using a wider opening.
The fiber orientation technology provides a better shear surface for a cleaner cut. The fiber orientation technology aligns the fibers in the fill hole so the shearing action disrupts as few muscle cells as possible. The fiber orientation technology decreases the total area of metal fill plate blocking the meat flow resulting in less direction change to the product which works the meat. The fiber orientation technology pulls the meat fiber through the fill hole instead of pushing using the principles of the venturi/choke plate.
All of these characteristics of fiber orientation technology reduce the release and mixing of myosin with actin, the net effect is a controlled orientation of the fiber, less myosin activity resulting in a better bite/bind and control over the final cook shape.
Spherical geometry in fill or stripper plate creates venturi effects.
The process of the present invention makes a patty cool uniformly and soften the texture/bite of the product.
A food patty molding machine has a mold plate and at least one mold cavity therein. A mold plate drive is connected to the mold plate for driving the mold plate along a given path, and a repetitive cycle, between a fill position and a discharge position. A food pump pumps a moldable food product through a fill passage connecting the food pump to the mold cavity when the mold plate is in the fill position. A fill plate, interposed in the fill passage immediately adjacent to the mold plate has a multiplicity of fill orifices distributed in a predetermined pattern throughout an area aligned with the mold cavity when the mold plate is in fill position. The fill orifices define paths through the fill plate, wherein some of the paths each have a path portion obliquely angled or perpendicular to the fill side of the mold plate. The paths consist of spherical intersections or a curved structure. The side of the fill plate which is in contact with the stripper consists of a spherical hemisphere or curved structure which has a diameter approximately 1.1 to 2.5 times greater than a cylindrical portion which intersect the top of the mold plate perpendicularly or at an angle of less than or equal to about +/−75 degrees, or about +/−45 degrees in a preferred embodiment as measured from vertical in the longitudinal direction of the mold plate. By a reduction in the cross-sectional area a “choked-flow” condition is created. By using spherical sections or a curved structure, intersections between cylinder and spheres or curved structures create transitions which can be manufactured whose geometry approaches a venturi style system. It is preferred to have a sharper edge from the edge to the hole. To get a perfect edge it is preferred to sharpen with a grinder.
In a preferred embodiment, the fill plate is chrome coated on the side adjacent to the stripper plate with a material significantly harder than the fill plate material. This is because the stripper plate wears out. The piece is approximately 39 Rockwell C. It becomes approximately 60-65 Rockwell C. The material is applied in a thickness to facilitate a surface which cuts the food product upon movement of a stripper plate. The material goes from about 1/1000 th of an inch to about 10/1000 th of an inch with the chrome. A cutting hemisphere into bottom of plate, with a cylinder.
A stripper plate is interposed in the fill passage immediately adjacent to the fill plate. The stripper plate is movable in a direction transverse to the mold plate, between the fill and discharge locations. The stripper plate has a multiplicity of fill openings aligned one-for-one with the fill orifices in the fill plate when the stripper plate is in fill position. A stripper plate drive is synchronized with the mold plate drive, such that the movement of the stripper plate facilitates the cutting of the meat product, which was pushed through the fill plate by the food pump. The stripper plate drive moves the stripper plate to its discharge position, in each mold cycle, before the mold plate moves appreciably toward the discharge location. The stripper plate drive maintains the stripper plate in the discharge position until the mold plate cavity is displaced beyond the fill orifices.
The fill paths can be in a direction to the front or rear of the machine. All fill paths consist of a hemispherical shape which is intersected by a cylindrical shape at an angle less or equal to about +/−75 degrees of vertical, and preferably about +/−45 degrees of vertical.
The use of spherical geometry, with cylindrical intersections, and the ratio of the diameter of the sphere divided by the diameter of the cylinder is approximately 1.1 to 2.5 creates conditions to meat flow which maintain improved cell structure.
Using conservation of mass and conservation of energy principles the volume rate of flow must be equal at all points in the systems. (ρA 1 V 1 =(ρ 2 A 2 V 2 ). Since ρ is a constant, velocity is inversely proportional to cross sectional area. Also, a venturi requires a ramp of some finite distance and a throat which also has a finite distance.
A spherical geometry feeding into a circular cross section which creates a product velocity increased while maintaining more consistent pressure on the meat. A sphere has the following properties:
All points on a sphere are the same distance from a fixed point. Contours and plane sections of spheres are circles. Spheres have the same width and girth. Spheres have maximum volume with minimum surface area. These properties allow meat to flow with minimum interruptions. There are no static or dead zones. No matter what angle the cylinder intersects the sphere; the cross section is always a perfect circle. Pressure inside of a sphere is uniform in all directions.
When meat is passed through a circular cross section of a sphere, the fact that pressure is uniform in a sphere creates forces which will be coaxial with the sphere. The reduction in area accelerates the meat through the cylindrical section of the fill plate. The acceleration has been shown empirically to align fibers in the primary direct of flow. Hence, there is fiber orientation. | An apparatus and method for accelerating food product in order to cause the product to be stretched aligning the fibers of the product. | 0 |
BACKGROUND OF THE INVENTION
Field of the Invention
This invention is directed to a device for contactless detection of glass sheets in movement, with a reflective photoelectric barrier, in installations of the glass industry, and in particular in installations for production of bent and/or tempered glazings, which is operational even in hot zones and/or in disturbed atmosphere.
Description of the Related Art
Actually, in glass installations, it is necessary to be able to identify the passage of each glass sheet at given points. This identification in space and time makes it possible to control the triggering of a subsequent operation or operations for treating the glass sheet, or of an operation for correcting the positioning of the latter.
Now, it happens that the market requires increasingly complex glazing shapes, which involves increasingly improved operations for treating glass sheets. The detection then becomes an essential stage for assuring the good synchronization of these operations. It is therefore necessary to develop ever more reliable, quick, precise detectors, whatever their location in the installation may be, such as, for example, the glory hole, or any other zone of an automatic installation for bending and/or tempering glass sheets, in particular for obtaining automobile glazings.
In this case, the sheets to be detected have a temperature, during their movement into the furnace up to the bending cell, which increases until exceeding their softening temperature, the bending being performed at between 500° and 700° C.
It thus is known to place a detector increasingly far into the production line, in zones with more or less high temperature, and, moreover, having a tendency to be disturbed by slight stirrings of air due to the repeated openings of the doors of said zones among whose number are counted, for example, the glory hole, or the cell for bending or even for tempering.
These openings must, nevertheless, have the equipment for bending and/or tempering circulate from one zone to the other.
This increasingly "slow" detection makes it possible to reduce to a maximum the distance between the location where the sheet is detected and the location where the operation, activated by the detection on said sheet, is triggered. Thus, the uncertainties in the detection are limited, and consequently, in the subsequent operations that it triggers, uncertainties resulting from accidental events which can occur on the sheet between these two locations are limited.
The first detectors proposed were optical detectors whose operation was based on the principle of the emission of a light beam in the transport plane of the glass sheet, a light beam whose cutoff during the passage of said sheet is identified. Thus, any contact between detector and sheet that can cause marking of the latter was avoided when it went beyond its softening point.
But these beams are greatly disturbed when they go through layers of air having slight temperature differences. This is particularly true when the distance to be passed through by the light beams is great. This leads to path deviations of the beams which are more or less refracted, causing a completely erroneous detection.
To eliminate this problem, other detectors have then been used, such as mechanical detectors, an example of which, consisting of a retractable pin integral with a roller conveyor, is described in patent EP-B-0217708. The latter exhibit the advantage of being entirely insensitive to the temperature of the outside environment and of being able to be easily moved over the entire width of the transport plane of the sheet. Actually, the position of the retractable pin along its roller can easily be modified. Now, it is important, precisely, to have an easily movable detector, so as to select the point of detection as a function of each type of glazing, depending on its dimensions and the configuration of the edge that it is desired to detect.
As a rule, marking of the sheet is avoided, because from the first impact between the sheet in movement and the detection pin, the latter tilts. But in this process of detection, a cylinder, jointed on the lever arm integral with the detection roller, operates which can pose problems of reliability, in particular due to a reaction delay time. There therefore exists a risk of possible marking of the sheet with this type of detector, that can compromise the optical quality of the latter if it has already reached its softening temperature.
The pneumatic detectors, such as those described in patent application EP-A 0348266, have the advantage of detection a sheet without contact with the latter. They consist either of an emitter and a receiver of pressurized gas placed on both sides of the transport plane of the sheet, the receiver detecting the cancellation of the pressure due to the passage of the sheet; or of an emitter and receiver both placed under the transport plane, the receiver detecting, this time by reflection, the pressure difference induced by the passage of the sheet. In both cases, to maintain a good precision and a reasonable response time, it is necessary to position the emitter very close to the glass sheet, at a distance on the order of several millimeters. Any chance deviation relative to this quite precise distance causes errors in the detection. To avoid such deviations is nevertheless not easy, for example, in the high temperature zones causing a certain expansion of the equipment. Moreover, the thicknesses of the glass sheets are variable. It is therefore necessary to adjust again, with each new production, the location in the vertical plane of the emitter and the receiver, which is at times quite difficult.
Efforts have also been made to improve the optical detection systems, but this time by guiding the light beams. Patent application EP-A-0267850 specifies guiding these beams by bundles of optical fibers, which are particularly suitable for any installation configuration.
But the use of such glass fibers, however, is problematic in too hot an environment, because the fibers, damaged by the too great heat, have a tendency to break, in the long run, even if an attempt is made to cool them by surrounding them with a sheath in which a cooling fluid circulates. And, in any case, the output of these fibers, even with this protective sheath, is relatively vulnerable to the very great heat.
Such a gradual deterioration of the fibers under the immediate influence of very high temperatures causes a reduction of the intensity of the light beams, to a threshold where the detection loses all reliability.
SUMMARY OF THE INVENTION
This invention therefore has as its object a detection device eliminating all these drawbacks, in particular by offering a precise, quick detection of the presence of a glass sheet in movement, and which is not disturbed in the hot zones whose temperature can exceed the softening temperature of the glass, and/or in the zones with stirring of air.
The device according to the invention makes it possible to detect without contact, glass sheets in movement in glass installations by using a reflective photoelectric barrier comprising an emitter and a receiver of light beams, said beams following a path in a channel of heat-resistant material, whose walls delimit a homogeneous isothermal environment, this channel emerging in the vicinity of the sheet to be detected.
By channel is meant a waveguide, which exhibits the feature, according to the invention, of having a large-sized section, without a dimension common with those of the optical fibers, a section, for example, on the order of several square centimeters.
By selecting an optical detection, any danger of marking is eliminated. Moreover, by choosing to have the light beams follow a path in a channel, the risks of diffraction and/or deviation that free light beams incur in disturbed zones are also eliminated, as has already been explained. Moreover, the selection of a channel of heat-resistant material will make it possible to use it in high-temperature zones which damage waveguides such as optical fibers.
Said channel preferably consists of a metal pipe.
Advantageously, it is possible to choose to obtain a path of the emitted beam leaving the channel which is approximately perpendicular to the transport plane of the sheet to be detected. Actually, when it is desired to detect an edge of a sheet in movement, the detection will be more precise if the beam is reflected virtually perpendicular to said edge.
Various variants of the device can be proposed. If, for example, it is a matter of a detection while the transport plane of the sheets is vertical, the light beam can enter by a section of the pipe and come out through the other. But if the transport plane is, for example, horizontal and it is not possible to place the pipe easily so that the beam leaving the pipe by a section can go through this transport plane, it is necessary to consider providing it with optical parts resistant to high temperature, which will make it possible to have the light beams at best follow a path, and mainly to focus them in the zone of passage of the glass sheets.
Said optical parts can be further treated with a nonglare coating.
Thus, a lateral output can be drilled in the wall of the pipe and a heat-resistant prism can be placed in the pipe, bending the path of the emitted light beam toward the lateral output. Therefore, it is possible to adapt the device according to the invention to any installation configuration: actually, regardless of the inclination of the longitudinal axis of the pipe relative to the transport plane of the sheet, the prism is positioned to have the desired output path. It should be noted that it is possible to position the prism to obtain a better selectivity of the light beams reaching the receiver.
Actually, it is desirable to incline the prism so that the perpendicular to the first face encountered by the light beam emitted from the prism is not completely parallel to said beam, the angle of inclination being in general less than 10°, as a function of the characteristics of the optical parts. Thus, it is avoided that the receiver receives stray light beams coming from the reflection of the light beam emitted on the faces of the prism.
The precision of the detection is all the better the more precisely the light beam is focussed on the glass sheet, creating a light "spot" all the more localized and faster to analyze the smaller it is. For this focussing, it is possible to provide, opposite the output, a first lens: the latter makes possible an optimal focussing of the emitted beam leaving the pipe on the sheet to be detected.
It is also possible, for example, to place a second lens in the input section of the emitted beam, to channel the path of the beam parallel to the walls of the pipe.
It is specified that it is advantageous to have a small-sized, almost pinpoint light source, so as to have to focus the smallest light beam possible. Thus, the precision will be optimal. For this purpose, it is possible to use an emitting diode as an emitter.
The light beams emitted and received are advantageously centered on a well-selected wavelength, which can be selected in the entire range that can go from ultraviolet to infrared. It is possible to select, for example, a wavelength of the infrared range provided that it is well known how to process signals in this range and that powerful emitters exist in this same infrared range. Moreover, the emitter emits the light beam by amplitude modulation. The receiver is capable of identifying, on return, the reflected light ray thanks to its particular wavelength and to filter it by putting aside all other unwanted infrared radiations, which increase in heated chambers like a glory hole. The modulation makes it possible to eliminate the continuous component of parasitic radiation of the same wavelength.
Advantageously, it is possible to place near the output of the channel a protective part such as a cone, whose widest section is applied to said opening. It makes it possible to guard the optical parts against possible falling dust or cullet.
It is possible, for example, to place the channel in a plane parallel to the transport plane of glass sheets to be detected: this can prove practical, in a glory hole of a bending/tempering installation, where the plane parallel to the roller conveyors and particularly below the latter is an accessible and not very cluttered zone; it is consequently sufficient to adjust the prism.
The channel comes out, for example in this case, at a distance between 50 and 80 mm from the transport plane of the glass sheet to be detected. A very significant advantage becomes apparent here: it is possible to place this channel at a fairly great distance from the sheet, without affecting the precision of the detection. Further, since it is relatively far from the rollers, there is no danger of holding back possible bits of broken glass, jammed between roller and device.
The channel is thus placed under the rollers, and not between them, the channel is then much more accessible. This position of the channel makes it possible to move it very easily to the location where it is desired to perform the detection, all along the path of the roller conveyors. As indicated above, the maximum precision is obtained when the beam is perfectly focussed on the glazing; however, the detection device according to the invention is perfectly effective even if said distance undergoes deviations, in the range indicated above, from 10 to 15 mm. There is therefore no need to make complex and repetitive adjustments to determine the good position in height of the detector. Moreover, the fact that the channel is clearly below the rollers avoids an accumulation of undesirable cullet between the rollers and the channel. The possible cullet can flow out here without any problem on both sides of the channel.
It is possible to choose to emit the light beams from the emitter and the receiver to the input of the channel and/or inside the latter, at the very least over a certain length of this channel by optical fibers. The latter are actually a waveguide that is particularly practical in use and very suitable if they are not exposed to too great heats.
BRIEF DESCRIPTION OF THE DRAWINGS
The details and advantageous characteristics of the invention are now described with reference to the accompanying drawings in which:
FIG. 1 is a diagram of an embodiment of the detection device according to the invention; and
FIG. 2 is a diagram of the channel belonging to said device, in place under the roller conveyors of a glory hole of an installation for bending and/or tempering glass sheets.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
In the two figures, for the sake of clarity, the relative proportions of the various diagrammed elements have not been observed.
In FIG. 1, the detection device has therefore been represented according to a nonlimiting embodiment of the invention. In a known manner, an emitter/receiver 3 of light beams is placed sheltered from any heat source. The emitter can be an emitting diode, an almost pinpoint light source. Emitted beams 4 are centered on a selected frequency and modulated in amplitude. In this example, a frequency in the infrared range has been considered.
In a known manner, the receiver translates the received light beams into electric pulses, subsequently processed and used by a processing unit 1 connected electrically 2 to the receiver.
The emitted beam follows a path from emitter/receiver 3 to the vicinity of a sheet 11 to be detected, going through an elongate channel 6. It enters by a section of the channel and can go out either by the other section or by a lateral output. In this example, a lateral output has been selected. The reflected beam follows the same path in reverse direction.
Still according to this example, the path goes partly through a sheltered zone that is not hot, which extends from an emitter/receiver 3, and partly through a disturbed and/or very hot zone, such as a furnace, for example, where sheet 11, whose presence and/or position it is desired to be detected, is found.
Outside the hot and/or disturbed zone, the beams can be guided from emitter/receiver 3 by any known means, such as, for example, here, by optical fibers 10, which constitute a particularly effective waveguide when they are not exposed to high temperatures. Here, very advantageously, the output face of the optical fibers will act as an almost pinpoint light source. It should be noted that the latter can have a variable length according to the configuration of the installation and according to the positions of emitter/receiver 3 and processing unit 1. It is even possible not to use such a guide 10, but this then leads to bringing emitter/receiver 3 near the hot zone, which can pose problems of protecting the latter relative to the radiated heat and/or problems of bulkiness in a handling zone. Or then, it is necessary to organize very precise and immutable paths for the free light beams, which is perhaps not very practical if it is desired later to modify the installation configurations.
As soon as the beams penetrate the hot and/or disturbed zone, the device designed according to the invention makes it possible to provide the latter with a path in an isothermal and homogeneous environment, sheltered from movements of hot air close to the sheet. This result is obtained by channel 6, whose walls delimit such an environment. Nevertheless, it is obvious that such a channel can, a fortiori, guide the beams during their path in a sheltered and/or not hot zone.
According to the embodiment represented, channel 6 consists of a metal pipe with a 5 cm×5 cm square section, of variable length depending on the configuration of the installation and depending on the point of passage where it is desired to detect sheet 11.
This length can increase to correspond to the width of the installation, it then is necessary to make certain that the pipe does not have a tendency to bend when it is subjected to high temperature if it is relatively long.
This channel is equipped with three optical parts, preferably of silica, a material which is resistant at a temperature greater than 1000° C.: First of all, a first lens 5 is placed at the end of the pipe where emitted light flux enters and is intended to channel the latter into said pipe. A prism 9 is positioned in the outlet of the pipe, determining the end of the path parallel to the plane of the pipe of the emitted beam. The beam, by striking the prism, is reflected and leaves again in a selected direction, here almost perpendicular to the axis of the pipe in the diagrammed embodiment. The third part is a lens 7 at the outlet to refocus the beam reflected by the prism. It is placed on the lateral output for said beam arranged in the wall of the tube. To give numbered particulars relative to FIG. 1, it is possible, for example, to use input and output lenses of 75 mm focal distance, of 40 mm diameter and of plane convex type. The channel can have a length of 1.80 m, and the diameter of the optical fibers can be 1 to 2 mm. It then is advantageous, by considering this data, to incline the prism along a given axis with a value of about 1/5 of a degree: it is sufficient to prevent the receiver from picking up unwanted rays reflected on the faces of the prism.
In this example, a part of the outlet intended to protect the optical parts from falling cullet has been added. It involves a cone 8, preferably metal, whose largest diameter is adjusted based on the output of the emitted beam.
It further is possible to equip channel 6 with a gas intake such as a very fine pipe, not represented in FIG. 1, which enters the channel, for example, at the input section of the emitted beam, and which comes out both close to prism 9 and close to lens 7 while still inside the channel. This pipe, fed by gas, then makes it possible, by blowing very gently on each of these optical parts, to rid them of possible traces of dust and/or scale.
According to FIG. 2, the possible position of the channel in a section of a glory hole of a bending and/or tempering installation is indicated. It is obvious that this arrangement is given only by way of example, and that the position of the channel according to the invention can be considered at any usual location of detection of glass sheets of a glass installation.
This diagram, for simplification, indicates only the roller conveyors of the furnace. Channel 6 is advantageously under these rollers, parallel to one of them, one of its ends being outside the furnace. Thus, it is accessible for adjustments. The emitted beam, going out perpendicularly to the pipe, also strikes perpendicularly the moving sheet 11.
The free path of the emitted beam leaving said channel before encountering the glass sheet is 65 mm here, but can vary between 50 and 80 mm. Even if deviations of 10 to 15 mm occur in this range of length, the latter do not cause significant problems in the detection such as an inaccuracy or an increase of response time.
Therefore, it is found that such a channel is very suitable: according to the diagram, it can be seen that it is possible to move it easily over the entire width of the rollers as well as to move it close to this or that roller over the entire length of the set of rollers.
The detection by such a device is extremely fast and precise. | A device for contactless detection of glass sheets in movement in glass installations, using a reflective photoelectric barrier, includes an emitter and a receiver (3) of light beams (4). The light beams follow a path in a channel (6) of heat-resistant material whose walls delimit a homogeneous isothermal environment, the channel emerging in the vicinity of sheet (11) to be detected. | 6 |
FIELD OF THE INVENTION
[0001] The present invention relates to a heteropolymer or copolymer derived from two (or more) monomeric species, at least one of which incorporates a silicon atom. Such compounds have many uses including multiple applications in the semiconductor industry including patterning of templates for use in nanoimprint lithography.
BACKGROUND OF THE INVENTION
[0002] The improvement in areal density in hard disk drives using conventional multigrain media is currently bound by the superparamagnetic limit [1]. Bitpatterned media can circumvent this limitation by creating isolated magnetic islands separated by a nonmagnetic material. Nanoimprint lithography is an attractive solution for producing bit patterned media if a template can be created with sub-25 nm features [2]. Resolution limits in optical lithography and the prohibitive cost of electron beam lithography due to slow throughput [3] necessitate a new template patterning process. The self-assembly of diblock copolymers into well-defined structures [4] on the order of 5-100 nm produces features on the length scale required for production of bit patterened media. This is most efficiently accomplished by using the diblock copolymers to produce templates for imprint lithography [5]. With the availability of the proper template, imprint lithography can be employed to produce bit patterned media efficiently. Previous research has targeted a block copolymers that produce hexagonally packed cylindrical morphology with selective silicon incorporation into one block for etch resistance [6] through post-polymerization SiO 2 growth [7], silica deposition using supercritical CO 2 [8], and silicon-containing ferrocenyl monomers [9]. What is needed is method to create an imprint template with sub-100 nm features that can be etched.
SUMMARY OF THE INVENTION
[0003] The present invention contemplates silicon-containing compositions, methods of synthesis, and methods of use. More specifically, the present invention relates to a heteropolymer or copolymer derived from two (or more) monomeric species, at least one of which comprising silicon. Such compounds have many uses including multiple applications in the semiconductor industry including making templates for nanoimprint lithography.
[0004] In one embodiment, the invention relates to a method of synthesizing a silicon-containing block copolymer, comprising: a) providing first and second monomers (and, in some embodiments, additional monomers), said first monomer comprising a silicon atom and said second monomer being a hydrocarbon monomer (lacking silicon) that can be polymerized; b) treating said second monomer under conditions such that reactive polymer of said second monomer is formed; and c) reacting said first monomer with said reactive polymer of said second monomer under conditions such that said silicon-containing block copolymer is synthesized (e.g. a diblock, triblock etc.). In one embodiment, said second monomer is styrene and said reactive polymer is reactive polystyrene. In one embodiment, said reactive polystyrene is anionic polystyrene. In one embodiment, said first monomer is trimethyl-(2-methylene-but-3-enyl)silane. In one embodiment, said first monomer was synthesized in a Kumada coupling reaction (see reference 10) of chloroprene and (trimethylsilyl)-methylmagnesium chloride. In one embodiment, the conditions of step b) comprise polymerization in cyclohexane. In one embodiment, the method further comprises d) precipitating said silicon-containing block copolymer in methanol. In one embodiment, said silicon-containing block copolymer is PS-b-PTMSI. In one embodiment, said first monomer is a silicon-containing methacrylate. In one embodiment, said first monomer is methacryloxymethyltrimethylsilane (MTMSMA). In one embodiment, said silicon-containing block copolymer is Polystyrene-block-polymethacryloxymethyltrimethylsilane or, more simply, PS-b-P(MTMSMA). In one embodiment, said second monomer is a methacrylate. In one embodiment, said second monomer is an epoxide. In one embodiment, said second monomer is a styrene derivative. In one embodiment, said styrene derivative is p-methylstyrene. In one embodiment, said styrene derivative is p-chlorostyrene. In one embodiment, the silicon-containing block copolymer is applied to a surface, for example, by spin coating, preferably under conditions such that physical features, such as nanostructures that are less than 100 nm in size (and preferably 50 nm or less in size), are formed on the surface. Thus, in one embodiment, the method further comprises the step d) coating a surface with said block copolymer so as to create a block copolymer film. In one embodiment, the method further comprises the step e) treating said film under conditions such that nanostructures form. In one embodiment, said nanostructures comprise cylindrical structures, said cylindrical structures being substantially vertically aligned with respect to the plane of the surface. In one embodiment, said treating comprises exposing said coated surface to a saturated atmosphere of a solvent (a process also known as “annealing”), such as acetone or THF. In one embodiment, said surface is on a silicon wafer. In another embodiment, said treating comprises exposing said coated surface to heat. In one embodiment, the film can have different thicknesses. In one embodiment, said surface is not pre-treated with a cross-linked polymer prior to step d). In one embodiment, said surface is pre-treated with a cross-linked polymer prior to step d). In one embodiment, a third monomer is provided and reacted, and the resulting block copolymer is a triblock copolymer. In one embodiment, the invention contemplates a film made according to the process above. In one embodiment, the method further comprises the step f) etching said nanostructure-containing coated surface.
[0005] In one embodiment, the invention relates to a method of synthesizing a silicon-containing block copolymer, comprising: a) providing first and second monomers, said first monomer comprising a hydrocarbon monomer that does not incorporate silicon (i.e. lacking a silicon atom), said second monomer being a monomer that can be polymerized and comprising a silicon atom; b) treating said second monomer under conditions such that reactive polymer of said second monomer is formed; and c) reacting said first monomer with said reactive polymer of said second monomer under conditions such that said silicon-containing block copolymer is synthesized. In one embodiment, said second monomer is a silicon-containing styrene derivative. In one embodiment, said styrene derivative is p-trimethylsilyl styrene. In one embodiment, said second monomer is a silicon-containing methacrylate. In one embodiment, the method further comprises the step d) coating a surface with said block copolymer so as to create a block copolymer film. In one embodiment, the silicon-containing block copolymer is applied to a surface, for example, by spin coating, preferably under conditions such that physical features, such as nanostructures that are less than 100 nm in size (and preferably 50 nm or less in size), are formed on the surface. Thus, in one embodiment, the method further comprises the step e) treating said film under conditions such that nanostructures form. In one embodiment, said nanostructures comprises cylindrical structures, said cylindrical structures being substantially vertically aligned with respect to the plane of the surface. In one embodiment, said treating comprises exposing said coated surface to a saturated atmosphere of a solvent (a process also known as “annealing”) such as acetone or THF. In another embodiment, said treating comprises exposing said coated surface to heat. In one embodiment, the film can have different thicknesses. In one embodiment, said surface is on a silicon wafer. In one embodiment, said surface is not pre-treated with a cross-linked polymer prior to step d). In one embodiment, said surface is pre-treated with a cross-linked polymer prior to step d). In one embodiment, the invention relates to a method wherein a third monomer is provided and said block copolymer is a triblock copolymer. In one embodiment, the invention relates to a film made according to the process above. In one embodiment, the method further comprises the step f) etching said nanostructure-containing coated surface.
[0006] In one embodiment, the invention relates to a method forming nanostructures on a surface, comprising: a) providing a silicon-containing block copolymer such as PS-b-P(MTMSMA) and a surface; b) spin coating said block copolymer on said surface to create a coated surface; and c) treating said coated surface under conditions such that nanostructures are formed on said surface. In one embodiment, said nanostructures comprises cylindrical structures, said cylindrical structures being substantially vertically aligned with respect to the plane of the surface. In one embodiment, said treating comprises exposing said coated surface to a saturated atmosphere of a solvent (a process also known as “annealing”) such as acetone or THF. In another embodiment, said treating comprises exposing said coated surface to heat. In one embodiment, the film can have different thicknesses. In one embodiment, said surface is on a silicon wafer. In one embodiment, said surface is not pre-treated with a cross-linked polymer prior to step b). In one embodiment, said surface is pre-treated with a cross-linked polymer prior to step b). In one embodiment, the invention relates to a film made according to the process above. In one embodiment, the method further comprises the step e) etching said nanostructure-containing coated surface.
[0007] It is not intended that the present invention be limited to a specific silicon-containing monomer or copolymer. Illustrative monomers are shown in FIG. 12 . However, in one embodiment, a method of synthesis is contemplated for synthesizing a silicon-containing monomer, comprising reacting 2-chlorobuta-1,3-diene represented by the structure shown as (A) with ((trimethylsilyl)methyl)magnesium chloride (a Grignard reagent) represented by the structure shown as (B) so as to generate trimethyl-(2-methylenebut-3-enyl)silane represented by the structure (C) (see FIG. 1 ).
[0008] It is not intended that the present invention be limited to a specific monomer or copolymer. Illustrative monomers are shown in FIG. 13 . In another embodiment, a method of synthesis is contemplated comprising reacting a monomer such as styrene represented by the structure shown as (D) with sec-butyl lithium so as to generate a polystyrene anion represented by the structure (E) (see FIG. 2 ). The anionic polystyrene represented by the structure (E) can be further reacted with a silicon-containing monomer such as by the addition of trimethyl-(2-methylenebut-3-enyl)silane under such conditions as to generate a poly(styrene-trimethyl-(2-methylenebut-3-enyl)silane) dibolock copolymer represented by the structure (F) (see FIG. 2 ).
[0009] In another embodiment, a method of synthesis is contemplated comprising reacting a monomer such as styrene represented by the structure shown as (D) with sec-butyl lithium and subsequently with ethene-1,1-diyldibenzene (G) so as to generate a diphenyl ethylene end-capped polystyrene anion represented by the structure (H) (see FIG. 6 ). The diphenyl ethylene end-capped polystyrene anion represented by the structure (H) can be further reacted with addition of a silicon-containing monomer such as methacryloxymethyltrimethylsilane (MTMSMA) under such conditions as to generate a diblock copolymer, PS-b-P(MTMSMA) represented by the structure (I) (see FIG. 6 ).
[0010] In one embodiment, the invention relates to a method of synthesizing a silicon-containing copolymer, comprising: a) providing first and second monomers, said first monomer being a silicon-functionalized isoprene monomer and said second monomer being a monomer that does not incorporate silicon but can be polymerized such as styrene (e.g. in the case of styrene, it can polymerize because of the vinyl group); b) treating said second monomer under conditions such that a reactive polymer (such anionic as polystyrene) is formed; and c) reacting said first monomer with said reactive polymer (such as anionic polystyrene) under conditions such that said silicon-containing copolymer is synthesized. In one embodiment, said first monomer is trimethyl-(2-methylene-but-3-enyl)silane. In one embodiment, said first monomer was synthesized in a Kumada coupling reaction of chloroprene and (trimethylsilyl)-methylmagnesium chloride. In one embodiment, the conditions of step b) comprise polymerization in cyclohexane. In one embodiment, the conditions of step c) comprise anionic polymerization. In one embodiment the present invention contemplates, a further step comprising d) precipitating said silicon-containing copolymer in methanol. In one embodiment, said silicon-containing copolymer is PS-b-PTMSI, polystyrene-block-polytrimethylsilyl isoprene. In one embodiment, the silicon-containing block copolymer is applied to a surface, for example, by spin coating, preferably under conditions such that physical features, such as nanostructures that are less than 100 nm in size (and preferably 50 nm or less in size), are spontaneously formed on the surface. In one embodiment, the features have very different etch rates such that one block can be etched without substantial etching of the other. In a preferred embodiment, such nanostructures have a cylindrical morphology with the domain spacing of approximately 50 nm or less. In one embodiment, the nanostructures are hexagonally packed. Such conditions for forming nanostructures can involve annealing with heat or solvents. Alternatively, the surface can first be treated with a substance that imparts a desired surface energy such that the nature of the surface treatment controls or enables nanostructure development. Alternatively, the conditions can involve varying the thickness of the applied silicon-containing copolymer. However the nanostructures are made, in one embodiment, the method further comprises etching said nanostructures.
[0011] In one embodiment, the invention relates to a method of synthesizing a silicon-containing copolymer, comprising: a) providing first and second monomers, said first monomer being a silicon-containing methacrylate and said second monomer being a monomer that does not incorporate the element silicon and can polymerize such as styrene; b) treating said second monomer under conditions such that a reactive polymer such as polystyrene anion is formed; and c) reacting said first monomer with said reactive polymer (e.g. polystyrene anion) under conditions such that said silicon-containing copolymer is synthesized thus producing a block copolymer. In one embodiment, said first monomer is methacryloxymethyltrimethylsilane (MTMSMA). In one embodiment, the conditions of step c) comprise anionic polymerization. In one embodiment, further comprising d) precipitating said silicon-containing copolymer. In one embodiment, said silicon-containing copolymer is PS-b-P(MTMSMA).
[0012] In one embodiment, the invention relates to a method of forming nanostructures on a surface, comprising: a) providing a silicon-containing copolymer such as the PS-b-P(MTMSMA) copolymer and a surface; b) spin coating said copolymer on said surface to create a coated surface; and c) treating said coated surface under conditions such that nanostructures are formed on said surface. In one embodiment, said nanostructures comprise cylindrical structures, said cylindrical structures being substantially vertically aligned with respect to the plane of the surface. In one embodiment, said treating comprises exposing said coated surface to a saturated atmosphere of solvents such as acetone or THF (or other solvent that can dissolve at least one of the blocks in the copolymer and has a high vapor pressure at room temperature, including but not limited to toluene, benzene, etc.) In one embodiment, said surface is on a silicon wafer. In one embodiment, said surface is not pre-treated with a cross-linked polymer prior to step b). In one embodiment, said surface is pre-treated with a cross-linked polymer prior to step b). In one embodiment, nanostructures less than 100 nm in size (and preferably 50 nm or less) are made with the copolymer by annealing using heat or solvents (as described herein). In a preferred embodiment, such nanostructures are hexagonally packed cylindrical morphology with the domain spacing of approximately 50 nm or less. However the nanostructures are made, in one embodiment, the method further comprises etching said nanostructures. In one embodiment, the present invention contemplates compositions comprising thin films (e.g. spin-coated films) of silicon-containing copolymers comprising such nanostructures, e.g. films deposited on a surface.
[0013] Many combinations of diblock (or triblock or more) copolymers can be made. For example, the illustrative silicon-containing monomers ( FIG. 12 ) can be combined with any one or more of the hydrocarbon monomers ( FIG. 13 ) lacking silicon. Whatever the combination, it is preferred that a block copolymer contain over 12 wt % silicon in one block. This provides the etch selectivity to yield a 3-D pattern of self-assembled nanofeatures. Polymerization of these monomers can be done using a variety of methods. For example, epoxide polymers can be made using the methods of Hillmyer and Bates, Macromolecules 29:6994 (1996). Polymers of trimethylsilyl styrene are described by Harada et al., J. Polymer Sci. 43:1214 (2005) and Misichronis et al., Int. J. Polymer Analysis and Char. 13:136 (2008). Polymerization of the TBDMSO-Styrene monomer is described by Hirao, A., Makromolecular Chem. Rapid. Commun., 3: 941 (1982).
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] For a more complete understanding of the features and advantages of the present invention, reference is now made to the detailed description of the invention along with the accompanying figures.
[0015] FIG. 1 shows the synthesis of TMSI monomer. A non-styrene derivative with a lower boiling point for easier purification, the isoprene product monomer (TMSI) was synthesized via a Kumada coupling [10].
[0016] FIG. 2 shows the synthesis of PS-b-PTMSI.
[0017] FIG. 3 shows a Gel Permeation Chromatography (GPC) Chromatogram of the PS aliquot (red) and PS-b-PTMSI (green).
[0018] FIG. 4 shows a 1 H NMR spectrum of PS-b-PTMSI. The integral values were enlarged for clarity; numerical figures are shown in Table 2.
[0019] FIG. 5 shows a Differential Scanning Calorimeter (DSC) trace of PS-b-PTMSI.
[0020] FIG. 6 shows the anionic synthesis of PS-b-P(MTMSMA).
[0021] FIG. 7 shows the 1 H-NMR of PS-b-P(MTMSMA).
[0022] FIG. 8 shows a Gel Permeation Chromatography (GPC) chromatograms of PS aliquot (red) and PS-b-P(MTMSMA) (green).
[0023] FIG. 9 shows the Small Angle X-ray Scattering (SAXS) analysis of a sample of PS-b-P(MTMSMA).
[0024] FIG. 10 shows a THF annealed film with parallel orientation.
[0025] FIG. 11 show an acetone annealed film with perpendicular orientation.
[0026] FIG. 12 shows the structures of illustrative silicon-containing monomers.
[0027] FIG. 13 shows the structures of illustrative hydrocarbon monomers (lacking silicon).
[0028] Table 1 shows a Gel Permeation Chromatography (GPC) characterization of PS-b-PTMSI.
[0029] Table 2 shows 1 H NMR data for PS-b-PTMSI.
DEFINITIONS
[0030] To facilitate the understanding of this invention, a number of terms are defined below. Terms defined herein have meanings as commonly understood by a person of ordinary skill in the areas relevant to the present invention. Terms such as “a”, “an” and “the” are not intended to refer to only a singular entity, but include the general class of which a specific example may be used for illustration. The terminology herein is used to describe specific embodiments of the invention, but their usage does not delimit the invention, except as outlined in the claims.
[0031] In addition, atoms making up the compounds of the present invention are intended to include all isotopic forms of such atoms. Isotopes, as used herein, include those atoms having the same atomic number but different mass numbers. By way of general example and without limitation, isotopes of hydrogen include tritium and deuterium, and isotopes of carbon include 13 C and 14 C. Similarly, it is contemplated that one or more carbon atom(s) of a compound of the present invention may be replaced by a silicon atom(s). Furthermore, it is contemplated that one or more oxygen atom(s) of a compound of the present invention may be replaced by a sulfur or selenium atom(s).
[0032] Trimethyl-(2-methylene-but-3-enyl)silane is represented by the following structure:
[0000]
[0000] and abbreviated (TMSI) and whose polymeric version is
[0000]
[0000] and is abbreviated P(TMSI).
[0033] Polystyrene anion is represented by the following structure:
[0000]
[0034] Polystyrene-block-polytrimethylsilyl isoprene is represented by the following structure:
[0000]
[0000] and abbreviated PS-b-PTMSI.
[0035] 1,3-bis(diphenylphosphino)propane nickel (II) chloride is represented by the following structure:
[0000]
[0000] and abbreviated NiL 2 Cl 2 .
[0036] Styrene (which is indicated by “S” or “St”) is represented by the following structure:
[0000]
[0037] The present invention also contemplates styrene “derivatives” where the basic styrene structure is modified, e.g. by adding substituents to the ring (but preferably maintaining the vinyl group for polymerization). Derivatives of any of the compounds shown in FIGS. 12 and 13 can also be used. Derivatives can be, for example, hydroxy-derivatives, oxo-derivatives or halo-derivatives. As used herein, “hydrogen” means —H; “hydroxy” means —OH; “oxo” means ═O; “halo” means independently —F, —Cl, —Br or —I.
[0038] P-methylstyrene is an example of a styrene derivative and is represented by the following structure:
[0000]
[0039] P-chlorostyrene is another example of a styrene haloderivative and is represented by the following structure:
[0000]
[0040] Trimethyl(4-vinylphenyl)silane is another example of a styrene derivative and is represented by the following structure:
[0000]
[0000] and abbreviated TMS-St and whose polymeric version is
[0000]
[0000] and is abbreviated P(TMS-St).
[0041] Tert-butyldimethyl(4-vinylphenoxy)silane is another example of a styrene derivative and is represented by the following structure:
[0000]
[0000] and abbreviated TBDMSO-St and whose polymeric version is
[0000]
[0000] and is abbreviated P(TBDMSO-St).
[0042] Tert-butyldimethyl(oxiran-2-ylmethoxy)silane is an example of a silicon containing compound and is represented by the following structure:
[0000]
[0000] and is abbreviated TBDMSO-EO and whose polymeric version is
[0000]
[0000] and is abbreviated P(TBDMSO-EO).
[0043] 1,1-diphenylethene is represented by the following structure:
[0000]
[0044] Methacryloxymethyltrimethylsilane is represented by the following structures:
[0000]
[0000] and abbreviated (MTMSMA) and whose polymeric version is
[0000]
[0000] and is abbreviated P(MTMSMA).
[0045] Diphenyl ethylene end-capped polystyrene anion is represented by the following structure:
[0000]
[0046] Polystyrene-block-polymethacryloxymethyltrimethylsilane PS-b-P(MTMSMA) is represented by the following structure:
[0000]
[0047] For scientific calculations, room temperature (rt) is taken to be 21 to 25 degrees Celsius, or 293 to 298 kelvins (K), or 65 to 72 degrees Fahrenheit.
[0048] It is desired that the silicon-containing copolymer be used to create “nanostructures” “nanofeatures” or “physical features on a nanometer scale” on a surface with controlled orientation. These physical features have shapes and thicknesses. For example, various nanostructures can be formed by components of a block copolymer, such as vertical lamellae, in-plane cylinders, and vertical cylinders, and may depend on film thickness, surface treatment, and the chemical properties of the blocks. In a preferred embodiment, said cylindrical structures being substantially vertically aligned with respect to the plane of the first film. Orientation of structures in regions or domains at the nanometer level (i.e. “microdomains” or “nanodomains”) may be controlled to be approximately uniform, and the spatial arrangement of these structures may also be controlled. For example, in one embodiment, domain spacing of the nanostructures is approximately 50 nm or less. The methods described herein can generate structures with the desired size, shape, orientation, and periodicity. Thereafter, in one embodiment, these structures may be etched or otherwise further treated.
DETAILED DESCRIPTION OF THE INVENTION
[0049] Due to the need for nanofeatures that can be etched, silicon-containing monomers were pursued. It is not intended that the present invention be limited by the nature of the silicon-containing monomer or that the present invention be limited to specific block polymers. However, to illustrate the invention, examples of various silicon-containing monomers and copolymers are provided. In one embodiment, a monomer trimethyl(2-methylenebut-3-enyl)silane was synthesized. After purification over nBuLi, isoprene trimethyl(2-methylenebut-3-enyl)silane was successfully added on to a living polystyrene (PS) anion (E) in cyclohexane ( FIG. 2 ). 1 H-NMR analysis showed a mol ratio of 83:17 Sty:TMSI ( FIG. 4 ). Using the density of PS previously reported in the literature [11], and assuming the density of PTMSI is similar to that of polyisoprene (PI), the volume fraction of PS is approximated at 0.77. Small changes in the density of PTMSI produce relatively small changes in the volume fraction of PTMSI. According to literature [12], P(S-b-I) with fPI=0.24 produces cylinders of PI, therefore a cylindrical morphology is expected. GPC determined the PDI of the PS aliquot and PS-b-PTMSI to be 1.00 and 1.02, respectively with a total Mn of 65.7 kDa ( FIG. 3 ). DSC traces of the polymer showed two Tgs ( FIG. 5 ): one at 103° C., which is consistent with reported PS values, and another at −34° C., which is assumed to that of the PTMSI block. The reported Tg for PI is −73° C, 44 but due to the steric bulk of the TMS group, this number seems to be reasonable.
[0050] TMSI was successfully synthesized in good yield by a Kumada coupling reaction [10, 13] of chloroprene with (trimethylsilyl)methylmagnesium chloride ( FIG. 1 ). Anionic polymerization was selected for the diblock copolymer synthesis because of its capability to provide narrow polydispersity and its scalability. The diblock copolymer synthesis was successfully conducted in cyclohexane ( FIG. 2 ) with good control of molecular weight and polydispersity (Table 1). The gel permeation chromatogram shown in FIG. 3 demonstrates the successful growth of PS-b-PTMSI. The 1 H NMR spectrum ( FIG. 4 ) shows a molar ratio of 0.84:0.16 PS:P(TMSI) when integrating the five aromatic styrene protons against both the single olefin proton in the backbone of the P(TMSI) block and the 9 TMS protons (Table 2). Using the previously reported density of PS [11] and assuming the density of P(TMSI) is similar to that of polyisoprene (PI), the volume fractions (f) of each block were calculated. Fortunately, small changes in the density of P(TMSI) produce relatively small changes in the volume fraction of P(TMSI). According to existing literature [12], P(S-b-I) with f PI =0.24 produces cylinders of PI, therefore a cylindrical morphology of the P(TMSI) block is expected.
[0051] Colburn et al conducted a series of experiments that concluded a formulation with a minimum of approximately 12 wt % Si can serve as an etch barrier under standard O 2 RIE conditions versus PS [6]. Therefore, a block copolymer (BC) was designed that contained over 12 wt % silicon in one block but was all hydrocarbons (i.e. lacking silicon) in the other. This would provide the etch selectivity to yield a 3-D pattern of self-assembled features.
General Materials and Methods
[0052] Reagents. All reagents were purchased from Sigma-Aldrich Chemical Co. and used without further purification unless otherwise stated. AP410 and AP310 were purchased from AZ Clariant. THF was purchased from JT Baker. Chloroprene 50 wt % in xylenes was purchased from Pfaltz & Bauer. Cyclohexane was purified with a Pure Solv MD-2 solvent purification system.
[0053] Instrumentation. All 1 H and 13 C NMR spectra were recorded on a Varian Unity Plus 400 MHz instrument. All chemical shifts are reported in ppm downfield from TMS using the residual protonated solvent as an internal standard (CDCl 3 , 1 H 7.26 ppm and 13 C 77.0 ppm). Molecular weight and polydispersity data were measured using an Agilent 1100 Series Isopump and Autosampler and a Viscotek Model 302 TETRA Detector Platform with 3 Iseries Mixed Bed High MW columns against polystyrene standards. HRMS (CI) was obtained on a VG analytical ZAB2-E instrument. IR data were recorded on a Nicolet Avatar 360 FT-IR and all peaks are reported in cm −1 . Glass transition temperatures (T g ) were recorded on a TA Q100 Differential Scanning Calorimeter (DSC).
EXAMPLE 1
[0054] Monomer (TMSI). In a modification of a procedure from Sakurai [13], a 250 mL RBF with condenser was charged with freshly ground Mg turnings (2.2 g, 92.2 mmol), a catalytic amount of dibromoethane, diethyl ether (100 mL), and a stir bar. After stirring for 15 min at rt, the reaction mixture was brought to reflux, and chloromethyltrimethylsilane (10.6 mL, 76.8 mmol) was added drop-wise over 30 min. In a separate 1 L Round bottom flask (RBF) with addition funnel, a mixture of 1,3-bis(diphenylphosphino)propane nickel (II) chloride (1.3 g, 2.3 mmol), freshly distilled chloroprene (9.0 mL, 97.6 mmol, bp=58-61° C., 760 torr), and diethyl ether (500 mL) was stirred at 0° C. After nearly complete Mg consumption (2 h), the pale-gray Grignard solution was cooled, added drop-wise to the dark-red, chloroprene mixture over 30 min and stirred overnight at room temperature (rt). The yellow solution was quenched with H 2 O (500 mL) and extracted with ether (3×250 mL); the organic layers were combined, dried over MgSO 4 , filtered and concentrated in vacuo. Trimethyl-(2-methylenebut-3-enyl)silane (TMSI) was isolated by distillation (57-60° C., 66 torr) in moderate yield (6.5 g, 60%) as a clear liquid; 1 H NMR (CDCl 3 ) δ ppm: 6.380 (ddd, J=17.6, 10.8, 0.4 Hz, 1H), 5.121 (dd, J=17.6, 0.4 Hz, 1H), 5.052 (dd, J=10.4, 0.4 Hz, 1H), 4.903 (m, 1H), 4.794 (s, 1H), 1.711 (d, J =0.8 Hz, 2H), 0.007 (s, 9H); 13 C-NMR (CDCl 3 ) δ ppm: 144.141, 139.915, 114.142, 113.606, 21.190, −1.250; IR (NaCl) cm −1 : 3084, 2955, 2897, 1588, 1248, 851; HRMS (CI) 140.1021 calc, 140.1023 found.
[0055] Purifications. All purifications and polymerizations were performed under an Ar atmosphere using standard Schlenk techniques. [14] Styrene was vacuum distilled twice from di-n-butylmagnesium. TMSI was vacuum distilled twice from n-butyllithium. Cyclohexane was purified with a Pure Solv MD-2 solvent purification system. The cyclohexane was run through A-2 alumina to remove trace amounts of water followed by a supported Q-5 copper redox catalyst to remove oxygen [15].
[0056] Polymer. The styrene polymerization was initiated with secbutyllithium at 40° C. in cyclohexane. After 12 h, a 5 mL aliquot of polystyrene (PS) was extracted from the reactor and terminated with degassed methanol. Purified TMSI monomer was then added to the reactor drop-wise and reacted for 12 h, followed by addition of degassed methanol to quench the living anions. The block copolymer was precipitated in methanol, filtered and freeze dried in a 10 wt % benzene solution with 0.25 wt % butylated hydroxytoluene inhibitor to prevent oxidative degradation of the P(TMSI) backbone.
EXAMPLE 2
Synthesis of PS-b-PTMSI
[0057] Due to the problems associated with styrene derivatives, monomer trimethyl(2-methylenebut-3-enyl)silane was synthesized. After purification over nBuLi, isoprene trimethyl(2-methylenebut-3-enyl)silane was successfully added on to a living polystyrene (PS) anion in cyclohexane ( FIG. 2 ). 1 H-NMR analysis showed a mol ratio of 83:17 Sty:TMSI ( FIG. 4 ). Using the density of PS previously reported in the literature [11], and assuming the density of PTMSI is similar to that of polyisoprene (PI), the volume fraction of PS is approximated at 0.77. Small changes in the density of PTMSI produce relatively small changes in the volume fraction of PTMSI. According to existing literature 43, P(S-b-I) with fPI=0.24 produces cylinders of PI, therefore a cylindrical morphology is expected. GPC determined the PDI of the PS aliquot and PS-b-PTMSI to be 1.00 and 1.02, respectively with a total Mn of 65.7 kDa ( FIG. 3 ). DSC traces of the polymer showed two Tgs ( FIG. 5 ): one at 103° C., which is consistent with reported PS values [16], and another at −34° C., which is assumed to that of the PTMSI block. The reported Tg for PI is −73° C. [16], but due to the steric bulk of the TMS group, this number seems to be reasonable.
EXAMPLE 3
Synthesis of Trimethyl-(2-methylene-but-3-enyl)silane
[0058] In a modified procedure from Sakurai [13], a 250 mL RBF with condenser was charged with freshly ground Mg (2.2 g, 92.2 mmol), a catalytic amount of dibromoethane, diethyl ether (100 mL), and a stir bar. After stirring for 15 min at rt, the reaction mixture was brought to reflux, and chloromethyltrimethylsilane (10.6 mL, 76.8 mmol) was added drop-wise over 30 min. In a separate 1 L RBF with addition funnel, a mixture of 1,3-Bis(diphenylphosphino)propane nickel (II) chloride (1.3 g, 2.3 mmol), freshly distilled chloroprene (9.0 mL, 97.6 mmol, bp=58-61° C., 760 ton), and diethyl ether (500 mL) was stirred at 0° C. After nearly complete Mg consumption (2 h), the pale-gray Grignard solution was cooled, added drop-wise to the dark-red, chloroprene mixture over 30 min, and stirred overnight at rt. The yellow product was quenched with H 2 O (500 mL) and extracted with ether (3×250 mL); the organic layers were combined, dried over MgSO 4 , filtered, and concentrated in vacuo. Monomer 5.9 was isolated by distillation (57-60° C., 66 ton) as a clear liquid in moderate yield (6.5 g, 60%); 1 H NMR (CDCl 3 )_ppm: 6.380 (ddd, J=17.6, 10.8, 0.4 Hz, 1H), 5.121 (dd, J=17.6, 0.4 Hz, 1H), 5.052 (dd, J=10.4, 0.4 Hz, 1H), 4.903 (m, 1H), 4.794 (s, 1H), 1.711 (d, J=0.8 Hz, 2H), 0.007 (s, 9H); 13 C-NMR (CDCl 3 )_ppm: 144.141, 139.915, 114.142, 113.606, 21.190, −1.250; IR (NaCl) cm −1 : 3084, 2955, 2897, 1588, 1248, 851; HRMS (CI) 140.1021 calc, 140.1023 found.
EXAMPLE 4
Block Co-Polymer (BC) Purification
[0059] All reactions and purification were conducted under Ar atmosphere via standard Schlenk line techniques [14]. All glassware was flame dried and purged with argon five times prior to exposure to any solvent or monomer. Purification agents, n-butyllithium (2.5 M solution in hexanes, Aldrich), and dibutylmagnesium (1 M solution in heptane, Aldrich) were received as solutions, and the solvents were removed using vacuum, prior to mixing with monomers. Exposure to air was prevented by storing and handling the reagent bottles under argon atmosphere inside a dry-box. Lithium chloride (LiCl, Fluka) was stored in a 120° C. oven and repeatedly flame dried and purged when placed inside the reactor. 1,1′-Diphenylethylene (DPE) (97%, Aldrich) was freeze-dried and vacuumdistilled twice over n-butyllithium and stored under argon atmosphere inside a dry-box. DPE, which is a high boiling liquid (bp 270-272° C.) was distilled at 140-160° C. under continuous vacuum. High-purity Argon, used for maintain inert conditions, was passed through an OMI-2 organometallic Nanochem® resin indicator/purification column (Air Products). Methanol (reagent grade, Aldrich) used as termination reagent, was degassed by sparging with argon for 45 min for removing air (particularly oxygen), which can potentially couple “living” polymer chains leading to undesired products. All other chemicals were used as purchased. Styrene (99%, 10-15 ppm p-tert-butylcatechol inhibitor, Aldrich) was freezedried and then purified by two successive distillations over solvent-dried dibutylmagnesium (0.1 mmol/g styrene) at 40° C. for 2 h. The styrene burette was covered with aluminum foil to prevent photopolymerization and stored in a freezer. When ready for a reaction, the monomer was freeze-dried twice. Trimethyl-(2-methylene-but-3-enyl)silane was freeze-dried, and then dried over n-BuLi twice for at least 1 h at rt. After distilling a burrette, the monomer was freeze dried and used immediately. Methacryloxymethyltrimethylsilane (Gelest, SIM6485.5) was filtered through basic alumina on a bench top open of the air, and then freeze-dried in a solvent flask. After drying over calcium hydride two times for at least 1 h at rt, the monomer was distilled into a burrette. The monomer was covered in foil and stored in the freezer for up to two days.
EXAMPLE 5
PS-b-PTMSI
[0060] Trimethyl-(2-methylene-but-3-enyl)silane was freeze-dried, and then dried over n-BuLi twice for at least 1 h at rt. After distilling a burrette, the monomer was freeze dried and used immediately.
[0061] A 500 mL reactor was loaded with a stir bar, flame dried, and cyclohexane was added into the reactor via a solvent flask. The total volume of cyclohexane used was set to so that the final concentration was 5 wt % monomer. After heating the reactor to 40° C., sec-BuLi was added and stirred for 30 min to ensure a homogenous solution. Approximately 20 drops of purified styrene was then added to the reaction via an airlock and a burrette. The color of the solution slowly turned orange, and after a 20 min seeding period, the remaining styrene was added. After stirring overnight, 20 drops of TMSI was added via the airlock and a burrette. After a 20 min of seeding, the remaining TMSI was added to the colorless reaction. To quench the reaction, degassed methanol (5 mL) was added to the reaction and stirred for 30 min.
EXAMPLE 6
PS-b-P(MTMSMA)
[0062] A silicon containing methacryloxymethyltrimethylsilane (MTMSMA) is commercially available from Gelest, Inc. Due to its higher MW and boiling point compared to MMA, the purification proved to be difficult. During the last distillation to remove alcohols, trioctylaluminum initiated MTMSMA polymerization. Attempts to remove alcohols by sodium hydride also led to polymerization. It was determined that alcohols could be removed by passing the monomer through an alumina plug, and then subjected to freeze, pump, thaw cycles and distillation over calcium hydride. This monomer was successfully incorporated PS-b-P(MTMSMA) ( FIG. 6 ).
[0063] 1 H NMR analysis showed a mol ratio of 73:27 Sty:MTMSMA ( FIG. 7 ). Using the density of PS previously reported in the literature 12 and assuming the density of PMTMSMA is similar to that of PMMA, the volume fraction of PS is approximated at 0.66. Similarly to PS-b-PTMSI, small changes in the assumed density of P(MTMSMA) produce relatively small changes in the its volume fraction. According to the literature, 11 this volume fraction should yield a cylindrical morphology. GPC determined the PDI of the PS aliquot and PS-b-PTMSI both to be 1.17. The Mn of the PS aliquot and final precipitated block was 60.0 and 75.2 kDa, respectively ( FIG. 8 ).
EXAMPLE 7
Synthesis of PS-b-P MTMSMA
[0064] Methacryloxymethyltrimethylsilane (MTMSMA) (Gelest, SIM6485.5) was filtered through basic alumina on a bench top open of the air, and then freeze-dried in a solvent flask. After drying over calcium hydride two times for at least 1 h at rt, the monomer was distilled into a burrette. The monomer was covered in foil and stored in the freezer for up to two days.
[0065] A 500 mL reactor was loaded with a stir bar and 5 molar equivalents of LiCl to initiator. LiCl suppresses side reactions during methacryloxymethyltrimethylsilane (MTMSMA) propagation [17]. Purified THF was added into the reactor via a solvent flask, and the reactor was cooled to −72° C. in a dry ice/IPA bath. The total volume of THF used was set to so that the final concentration was 5 wt % monomer. After the solution temperature was stabilized at −72° C., secBuLi was added and stirred for 5 min. Approximately 20 drops of purified styrene was then added to the reaction via an airlock and a burrette. The color of the solution immediately turned orange, and after a 20 min seeding period, the remaining styrene was added. This was stirred for 4 h followed by addition of 5 molar equivalents of DPE to initiator. This addition turned the reaction a deep red. After 3 h of stirring, 20 drops of MTMSMA was added to seed the MTMSMA via the airlock and a burrette, and this caused the reaction to turn colorless. The reaction was stirred for 4 h after the remaining MTMSMA was added. To quench the reaction, degassed methanol (5 mL) was added to the reaction and stirred for 45 min.
EXAMPLE 8
Small Angle X-ray Scattering
[0066] A sample of PS-b-P(MTMSMA) was analyzed via small angle X-ray scattering (SAXS). The data definitively show this block copolymer is phase separated at the nanoscale and that χN is of a sufficient value to induce order. The resulting Bragg's diffraction pattern displayed maxima at √3, √4, √7, indicative of a hexagonally packed cylindrical morphology. The domain spacing was calculated to be 49 nm. See FIG. 9 .
EXAMPLE 9
Solvent Annealing of PS-b-P(MTMSMA)
[0067] Thin films were spin coated on freshly oxidized wafers with a 1 wt % solution of PS-b-P(MTMSMA) in toluene. The wafers were then annealed under a saturated atmosphere of acetone or THF overnight in a covered glass petri dish. The resulting films were analyzed via AFM, and the images show both parallel ( FIG. 10 ) and perpendicularly ( FIG. 11 ) oriented cylinders depending on the solvent and film thickness. The size of the cylinders in these images is approximately 50 nm, which is consistent with the SAXS data.
REFERENCES
[0000]
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3. Ruiz, R., Kang, H., Detcheverry, F. A., Dobisz, E., Kercher, D. S., Albrecht, T. R., de Pablo, J. J., and Nealey, P. F. (2008) Density Multiplication and Improved Lithography by Directed Block Copolymer Assembly, Science 321, 936-939.
4. Bates, F. S., and Fredrickson, G. H. (1990) Block Copolymer Thermodynamics. Theory and Experiment, Annu. Rev. Phys. Chem. 41, 525-557.
5. Li, M., and Ober, C. K. (2006) Block Copolymer Patterns and Templates, Mater. Today 9, 30-39.
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7. Kim, H.-C., Jia, X., Stafford, C. M., Kim, D. H., McCarthy, T. J., Tuominen, M., Hawker, C. J., and Russell, T. P. (2001) A Route to Nanoscopic Sio 2 Posts Via Block Copolymer Templates, Adv. Mater 13, 795-797.
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9. Lammertink, R. G. H., Hempenius, M. A., Enk, J. E. v. d., Chan, V. Z.-H., Thomas, E. L., and Vancso, G. J. (2000) Nanostructured Thin Films of Organic-Organometallic Block Copolymers: One-Step Lithography with Poly(Ferrocenylsilanes) by Reactive Ion Etching, Adv. Mater 12, 98-103.
10. Tamao, K., Sumitani, K., and Kumada, M. (1972) Selective Carbon-Carbon Bond Formation by Cross-Coupling of Grignard Reagents with Organic Halides. Catalysis by Nickel-Phosphine Complexes, Journal of the American Chemical Society 94, 4374-4376.
11. Fetters, L. J., Lohse, D. J., Richter, D., Witten, T. A., and Zirkel, A. (1994) Connection between Polymer Molecular Weight, Density, Chain Dimensions, and Melt Viscoelastic Properties, Macromolecules 27, 4639-4647.
12. Khandpur, A. K., Foerster, S., Bates, F. S., Hamley, I. W., Ryan, A. J., Bras, W., Almdal, K., and Mortensen, K. (1995) Polyisoprene-Polystyrene Diblock Copolymer Phase Diagram near the Order-Disorder Transition, Macromolecules 28, 8796-8806.
13. Sakurai, H., Hosomi, A., Saito, M., Sasaki, K., Iguchi, H., Sasaki, J.-I., and Araki, Y. (1983) Chemistry of Organosilicon Compounds—165: 2-Trimethylsilyl-Methyl-1,3-Butadiene—a Versatile Building Block for Terpene Synthesis, Tetrahedron 39, 883-894.
14. Uhrig, D., and Mays, J. W. (2005) Experimental Techniques in High-Vacuum Anionic Polymerization, J. Polym. Sci. A. 43, 6179-6222.
15. Pangborn, A. B., Giardello, M. A., Grubbs, R. H., Rosen, R. K., and Timmers, F. J. (1996) Safe and Convenient Procedure for Solvent Purification, Organometallics 15, 1518-1520.
16. Odian, G. (2004) Principles of Polymerization, 4th ed ed., Wiley-Interscience, New York.
17. Allen, R. D., Long, T. E., and McGrath, J. E. (1986) Preparation of High Purity, Anionic Polymerization Grade Alkyl Methacrylate Monomers Polym. Bull. 15, 127-134. | The present invention describes the synthesis of silicon-containing monomers and copolymers. The synthesis of a monomer, trimethyl-(2-methylenebut-3-enyl)silane (TMSI) and subsequent synthesis of diblock copolymer with styrene, forming polystyrene-block-polytrimethylsilyl isoprene, and synthesis of diblock copolymer Polystyrene-block-polymethacryloxymethyltrimethylsilane or PS-b-P(MTMSMA). These silicon containing diblock copolymers have a variety of uses. One preferred application is as novel imprint template material with sub-100 nm features for lithography. | 1 |
BACKGROUND OF THE INVENTION
Plug valves for use in control of the flow of the particulate catalyst in catalytic convertors are shown in U.S. Pat. Nos. 2,668,755 and 2,850,364. The plug valves shown in these disclosures have served quite adequately. A valve of the plug type is typically installed in the bottom of a regenerator vessel. It is mounted adjacent a pipe or conduit which typically extends through the wall of the vessel to position the plug in close proximity to a valve seat, typically located at the end of a pipe or conduit. Catalyst flows through the pipe and is metered past the valve seat by the position of the tapered plug valve. The catalyst is an abrasive material which has a propensity for abrading and wearing away the metal components of the plug valve. This is particularly a problem with the stem below the plug. The stem must work through an opening of specified size in the body of the valve. The vessel itself is pressurized and hence, it is necessary to prevent leakage from the pressurized vessel along the stem where it inserts through the wall of the body of the valve. Moreover, it is desirable to prevent particulate catalyst from working into the spaces between the valve stem and its supporting structure. Particulate catalyst in this area wears the stem away and weakens the structure.
The apparatus of the present invention is an improved plug mounted on a protected stem. The stem is protected in a significant fashion which avoids the problem of stem erosion by the particulate catalyst. The protective plug valve of this particular invention can be used both for the metering valve which admits spent catalyst to the regenerator and the valve which controls the flow of regenerated catalyst from a dense phase fluid bed in a regenerator into a catalytic reaction vessel.
This apparatus is particularly useful in extending the life of a metering valve in a catalyst regenerator. Continued operation of a catalytic reactor, disengager and the catalyst regenerator that is cooperative therewith is essential. When they are brought on line, they are normally intended to operate for months and hopefully for more than one year. During the continued use of such equipment, the valves which control the flow of the particulate catalyst are subjected to the type of wear mentioned above. Wearing of the valve stem of the plug valves which control the flow of the catalyst can become so excessive as to wear through the valve stem and cause it to break. Breakage of the valve stem normally constitutes a catastrophic failure requiring emergency shutdown of the catalytic process and emergency repairs. Shutdown is normally scheduled where maintenance on all parts of the equipment can be completed. An emergency shutdown to repair a single component is extremely undesirable, particularly in view of the fact that the lost revenues may easily exceed several thousand dollars per hour. In view of these circumstances, it will be understood that protection of the valve stem is exceedingly important and this invention provides that type of protection. The present invention protects the valve stem against significant contact with the particulate catalyst. The catalyst may settle in the vicinity of the valve stem but it does not otherwise abrade the surface of the valve stem in significant measure. This invention thus extends the life of the stem substantially and avoids catastrophic shutdowns.
SUMMARY OF THE INVENTION
This invention is summarized as a plug valve for use in an environment of particulate catalyst. The plug valve is mounted on a stem. The stem is protected by the incorporation of a tubular shield attached to the upper portions of the stem. The stem travels upwardly and downwardly and carries the shield with it. The shield is spaced outwardly from and encircles the stem. The shield in addition has an internal cavity. The stem works up and downwardly in a guide tube which receives a flow of steam upwardly therethrough into the shield and a set of ports turn the flow of steam downwardly in a concentric jet of steam around the exterior of the guide tube and below the shield to prevent abrasive contact of the stem with the particulate catalyst.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a sectional view showing a lower regenerator chamber incorporating plug valves with improvements in accordance with the present invention;
FIG. 2 is an enlarged sectional view showing a protective shield which prevents abrasion of the valve stem by the particulate catalyst; and
FIG. 3 is a sectional view along the line 3--3 of FIG. 2 showing the details of construction of the apparatus.
DESCRIPTION OF THE PREFERRED EMBODIMENT
In FIG. 1, a regenerator vessel is identified by the numeral 10. A conduit 11 conducts particulate catalyst downwardly. The conduit is shaped at the bottom end to define a valve seat 12. The valve seat mates against a tapered plug 13. The plug 13 fits into the valve seat to plug the conduit 11. A fluid bed is accumulated in the bottom of the pressure vessel 10. The fluid bed includes particulate catalyst which has the ability to substantially abrade the valve stem. A movable stem reciprocates upwardly and downwardly and moves the tapered plug 13. The numeral 16 identifies a steam chest which is supplied with the steam from a line 17. The cavity 16 comprises a fitting which is located in the side of the flange 15 whereby the cavity 16 supplies steam upwardly to the protective shield.
Attention is directed to FIG. 2 of the drawing which shows the apparatus in enlarged view. The cavity 16 is shown below a tubular member 26 which rests on a guide tube 20. The guide tube 20 is stationary. It is fixed to the flange 15. The guide tube 20 encircles the lower end of the moving apparatus. The apparatus which is on the interior includes a movable stem tube 21. The stem tube 21 is hollow as shown in FIG. 2. It extends downwardly and connects to the rod 18 shown in FIG. 1. It is not necessary to be hollow to serve as a conduit but rather this provides some weight reduction. The stem tube 21 is somewhat smaller than the interior of the guide tube 20. This defines the upper portion of the cavity 16. Steam flows upwardly through the annular cavity. Steam is introduced through the line 17 which passes through the wall of the guide tube 20, thereby introducing steam into the annular portion of the cavity 16. The steam flows upwardly throughout the cavity 16.
The stem tube 21 slides interiorally of a tubular member 26 which has a number of ports at 24 at the lower end 25. The ports extend radially inwardly and stop short of the stem tube 21. The tubular members 21 and 26 define an annular space 28. Steam flows upwardly through the annular space 28. The lower end 25 of tubular member 26 encloses a guide ring 30. The ring 30 is positioned by planting the edge of the tubular member 26 over a bevel on the guide ring 30. The set of grooves 19 align with the ports 24 to direct steam flow along the desired path. The ring 30 aligns the stem tube for movement upwardly and downwardly. The annular cavity 28 extends upwardly to an upper guide ring 31. The ring 31 guides the stem tube 21 on movement through the tubular member 26. In conjunction with the ring 30, the two control the width of the annular space 28.
The guide tube 20 ends midway up the supporting structure and a support ring 36 is integrally joined thereto. The ring 36 supports for the tubular member 38 which with the tubular member 26 defines the annular cavity 39. Steam is introduced into the annular cavity 23 from the several grooves 19 in the tubular member 26. The steam flows upwardly through the grooves 37 into the annular cavity 39.
The tubular member 26 is fixed in location as mentioned above. It supports a top tubular member 42 between the tubular members 26 and 38. The member 42 is grooved with a number of slots at 43. The openings serve as an outlet for steam flowing in the annulus 39. The outlet opens within a shield member 45. The shield member 45 has a metal body on the interior of a refractory material 46 which is on the exterior. The refractory material provides a hard facing which is not abraded by the particulate catalyst impinging thereon.
The shield 45 defines an internal cavity 48. The shield 45 is closed across its top end 50 as shown in FIG. 2. The top end 50 of the shield is just below the plug valve element 13 as shown in FIG. 1. Indeed, it can be just a fraction of an inch therebelow to protect even the uppermost reaches of the neck of the valve stem.
The shield 45 is a concentric tubular member around the stem tube 21. The stem tube 21 imparts reciprocating vertical movement to the plug 13. The shield 45 is concentric about the stem tube 21 from the plug valve itself, for all intents and purposes, to the top of the guide tube. The tubular member 38 terminates at the member 42 previously mentioned. Stem 21 is substantially enclosed within the guide tube and the shield. The stem communicates necessary reciprocal movement to the valve plug itself.
The annulus 28 opens upwardly to an internal ring 51 mounted at the upper end of the tubular member 26. The ring 51 defines an annular opening which exhausts the steam flowing upwardly. As steam flows past the ring 51, it opens into the cavity 48 in the shield 45. Steam in the cavity 48 is thus introduced from both the annular space 28 and the annular space 39. It flows into the cavity 48 from two sources.
There is only a single outlet for steam introduced into the cavity. The single outlet for steam is through the annular space 55. The annulus 55 is defined by the inwardly protruding lip 56 appended to the bottom of the shield 45. The lip 56 extends inwardly towards the fixed tubular member 38, and is constructed with a hard facing material to resist erosion by flowing steam. The steam flowing through the gap 55 is jetted downwardly in a concentric ring around the tubular member 38, the support 36, or the guide tube 20, depending on their extended positions. Steam flowing downwardly from the annular gap 55 prevents catalyst from entering the cavity 48. The surfaces exposed to steam flow are preferably coated with a hard facing material. This also prevents catalyst from working into the narrow confines between the fixed and moving tubular members shown in FIG. 2. The flow of steam upwardly through the annular spaces 28 and 39 further ejects catalyst in the unlikely event that it enters into the cavity 48 within the shield 45. The brunt of the wear is experienced by the shield 45 which is provided with the hard faced surface 46. The hard facing on the surface enables the apparatus to endure for a substantially longer time.
Only a small volume of steam is required to protect the apparatus. The steam acts as a lubricant for the moving parts. The steam does not in any way affect the fluid bed which collects around the valve stem. Rather, it protects the valve stem from the particulate catalyst and prevents its intrusion into the working parts. The annulus 28 directs steam to engulf the surface of the stem 21 for the purpose of protecting it from direct contact with catalyst and especially the abrasive effect of catalyst in the narrow gap between the fixed and movable parts. The annulus 39 provides additional steam flow for the gap 55 which has a larger cross section than the annulus 29.
The stem shown in FIG. 2 is illustrated at the uppermost end of travel (normally associated with its cold position). The shield 45 is limited at the upper extremity of its movement. However, downward movement is permitted. On downward movement, the stem tube 21 moves downwardly and carries the shield 45 downwardly with it. The gap 55 is moved downwardly as the inwardly protruding lip 56 is moved downwardly. However, the gap 55 is constant in size, thereby continuing to eject the ring of steam jetted downwardly next to the side wall of the tubular member 38 thereby protecting its hardened surface 40.
This apparatus particularly extends the life of a valve stem. The shield and the jet of steam protect the apparatus. The valve stem is protected from erosion by the particulate catalyst by the flow of steam in the annulus 28. This protection enables the apparatus to function substantially longer without fear of interruption or shutdown as a result of catastrophic stem failure.
The foregoing is directed to the preferred embodiment. However, the scope hereof is determined by the claims which follow. | A plug type valve for use in handling the flow of particulate catalyst is disclosed. In catalytic cracking equipment, it is necessary to regenerate the catalyst. The flow of catalyst to and from the regenerator must be controlled. A plug valve is disclosed for control of the flow of catalyst and the valve includes a tapered spear-like plug formed of a sacrificial material mounted on a stem. The stem is protected against the abrasive action of the particulate catalyst by means of a cylindrical spaced shield below the valve element and a circular jet of steam ejected downwardly below the shield and parallel to the stem. | 5 |
BACKGROUND OF THE INVENTION
This application is a continuation-in-part of my application Ser. No. 08/666,139 filed Jun. 19, 1996, now U.S. Pat. No. 5,765,309.
In most commercial, industrial and institutional buildings, including schools, hospitals, hotels and similar type structures, double doors hung in metal frames are used. In many cases these doors are latched to a center post, called a mullion, that allow use of single doors in double door frames. In many instances the mullion is a movable hollow core mullion and can be removed to allow for large loads to be passed through the doors and then reinstalled. The mullion post holding systems currently in use employ sliding wedges, hold-down clips, wrap around brackets among other types of hold down devices and are attached with various kinds of screws or bolts to fittings in the floor and top of the door frame. These become worn, rusted, clogged with dirt and grime and generally deteriorate with use and age and are invariably painted over. It is with the removal and reinstallation of such mullions that problems occur thereby making it a time consuming job, requiring special tools and other measures to remove and replace the mullion.
PRIOR ART
Various attempts have been made to overcome the problems associated with removing and reinstalling movable mullions. Movable mullions that do not require screwing and bolting are known.
U.S. Pat. No. 2,275,730 issued on Mar. 10, 1942 to Casse discloses a removable mullion which is designed for overhead doors, and is held in place by a spring type clamp or latch to hold the mullion in place and allow for its removal and attachment.
U.S. Pat. No. 3,000,062 issued on Sep. 19, 1961 to McCandless discloses a mullion that is held in place by the use of pressure applied to the mullion during installation, and release upon removal.
U.S. Pat. No. 3,319,382 issued on May 16, 1967 to Hand shows a mullion unit that is forced over a base plate and held by friction, and is slid into an upper joint by additional friction and held in place by a screw type unit. The method of fixing the mullion in place is only broadly defined in this description.
U.S. Pat. No. 5,435,102 issued on Jul. 25, 1995 to McCarthy shows a mullion fastened to a base unit and hinged to allow its tilting into a horizontal position after it is released at the top of the doorway. The unit also allows for the complete removal of the mullion. The fastening device in this unit is a key operated lock.
U.S. Pat. No. 5,450,697 issued on Sep. 19, 1995 to Prucinsky is very similar to the McCarthy patent, assigned to the same assignee, which extends the McCarthy patent by using key operated locks at either end of the mullion for easier removal, as well as disclosing different base and top attachment units.
In both U.S. Pat. Nos. 5,435,102 and 5,450,607 which represent the most recent state of the art, devices that employ a keyed cylinder with a cam to actuate a plunger or mortise dead bolt are used. The key cylinder is a delicate mechanism depending on small sensitive springs and pins that are susceptible to moisture, freeze up, corrosion or heat. At the most crucial times during emergencies these systems can fail after lengthy non use and especially if the key can not be found readily.
Although these patents address the problem of providing removable mullions, they have many disadvantages as will become apparent hereinafter. Furthermore, none of them show the simple, durable, easy to use and maintain, inexpensive mullion latch of this invention which is friendly to the user and allows for easy and rapid removal and reinstallation of removable mullions, while at the same time providing a safe and secure system. My Canadian application for patent Ser. No. 2,207,535 filed Jun. 11, 1997 and laid open to inspection on Dec. 19, 1997, is equivalent to applicants copending U.S. application for patent Ser. No. 08/666,139 filed Jun. 19, 1996. It describes and claims a mullion latch that may be removed and installed without tools,
OBJECTS OF THE INVENTION
It is an object of this invention to provide a mullion latch that enables the rapid removal and reinstallation of a hollow mullion post that is simple, durable, easy to use, inexpensive, economical to make and easy to maintain and which is friendly to the user and is secure and vandal resistant.
It is also an object of this invention to provide a mullion latch for use at the top of the mullion post that is secure and tamper proof and allows for simple tools, such as a rod or even the shaft of a screwdriver, or other common tool such as the handle of a pliers, for the removal of the mullion post, and still allow for reinstallation by one person without the use of any tools. It is a primary object of this invention to provide a security system of a mullion latch and post without sacrificing safety which is durable and functions in a fail safe manner after repeated usage.
It is still a further object of this invention to provide a secured mullion latch which may be adapted for use in combination with a variety of mullion shapes that are employed in double door mullion assemblies. It is another object of this invention to provide adapters for use with the mullion latch of this invention with the variety of hollow core mullion shapes in use in double door mullion assemblies.
It is another object of this invention to provide an assembly kit for retrofitting or adapting existing mullions to be readily removable and reinstallable which includes the mullion latch of this invention combined with an adapter for use with a variety of hollow mullion shapes and a disengaging tool.
It is a further object of this invention to provide a mullion latch which is easy to operate under any conditions day or night, that does not have to be touched during reinstallation of the mullion post and which one person can handle in either the removal or reinstalling operation. It is a further object of this invention to provide a mullion latch which will not allow the mullion post to fall out even if the latch is tripped. It is a further object of this invention to provide a mullion latch which is aesthetically neat and clean and will not be clogged up with dirt and grime and which is durable and requires little or no maintenance.
These and other objects and advantages, which are accomplished by the mullion latch, the adapters and the retrofit assembly kit of this invention, will become apparent from the description and accompanying drawings which illustrate preferred embodiments of this invention. A brief description of the Drawings or Figures follows.
THE FIGURES
FIG. 1 is an elevation view of a double doorway viewed from the inside having swinging doors in closed position, mounted within a metal frame, with a removable mullion between the doors having locking and opening mechanisms such as panic rim hardware.
FIG. 2 is an expanded elevation view from the inside of the doors, showing the mullion latch secured in the top frame or header of the double door frame.
FIG. 2a is an expanded elevation view from inside of the swinging doors, showing the floor plate and its retaining protrusions for engaging the mullion post in a vertical position.
FIG. 3 is an isometric view of the mullion latch of this invention, showing the housing engaged with a fragmentary portion of the upper part of a mullion post, having a cut-out of the top and side of the housing to show the lever or latch bar. Also shown is a cut-out of the back of the mullion post showing the back of the housing with a metal rod passing through openings in the backs of both the lever bar and the housing, which rod may be used to disengage the latch bar.
FIG. 3a is an isometric view of the cover, which may be made of metal, plastic or other material. The cover is made to plug into the housing of the mullion latch to cover the opening for inserting the disengaging tool illustrated as a rod which may be used to disengage the lever (latch) bar. The cover hides from view and protects the lever bar from dirt and grime and gives the appearance of a continuous mullion post.
FIG. 3b is an isometric view of the inside of the cover showing the disengaging device attached to the inside back of the cover.
FIGS. 4, 5 and 6 are sectional side, back and bottom views, respectively, in general alignment with each other, showing the detail of the mullion latch including the housing and lever bar mounted on the top of a fragmentary portion of the upper part of a mullion post.
FIGS. 7, 8 and 9 are sectional side views of the mullion latch including the housing and latch (lever) bar showing the progressive operating stages of the mullion latch bar in successive operating modes of removing the mullion from its installed position. The installation mode is essentially the reverse of the operation stages shown.
FIGS. 10, 11 and 12 are isometric views of three different mullion posts that are in commercial use also showing adapters of this invention for retrofitting the mullion posts to employ the mullion latch of this invention.
BRIEF DESCRIPTION OF THE INVENTION
The following Brief Description of the Invention is best understood with reference to FIG. 3, which is an isometric view of the secured mullion latch of this invention, showing the housing engaged with a fragmentary portion of the upper part of a hollow mullion post, having a cut-out of the top and side of the housing to show the lever (latch) bar. Also shown is a cut-out of the back of the mullion post which shows the back of the housing and the disengaging device, which is illustrated as a rod, which may be used to release the latch bar. The rod which passes through openings in the back of the lever bar, 21, and the back of the housing, 7, which openings create a passage for the rod through the housing and underside of the lever bar. The rod releases the lever bar from its engaged position when downward pressure is applied on the exposed portion of the rod, thereby permitting the removal of the mullion post.
The mullion latch, 1, in accordance with this invention is preferably rectangular in shape and comprises a housing, 1a, and a lever bar, 2, including a pivot pin, 3. The housing has a top, 4, two sides, 5, that are equivalent in shape, a front, 6, and a back, 7. The top, 4, of the housing, is adapted so that it may be secured in the center of the header of a double door frame, for example by screws, 32, as shown in FIGS. 1 and 2. The front, 6, and back, 7, of the housing face the outside and inside of the doors, respectively. The two sides, 5, of the housing have an extension, 9, that goes on the outside of the mullion post, 10, (shown in the engaged position), and below the joint, 11, made between the bottom- lips, 12, and the top-lip, 13, of the mullion post, 10. in similar manner the front, 6, of the housing extends so that the front bottom-lip, 12, also fits onto the top-lip, 13, of the mullion post, 10, when it is locked. The front, 6, of the housing is shaped to have two front-wings, 8, that fit within the sides, 5, of the housing, Ia. The front bottom-lips, 12, of the front-wings, 8, of the housing also fit onto the top side-lips, 13, of the mullion post, 10. An extension, 14, of the back, 7, of the housing extends below the two sides, 5, and is shaped to go inside the back top-lip, 13, of the mullion post, 10, when engaged. The back, 7, of the housing is shaped to have two back-wings, 15, that fit within the mullion post, 10, to form a channel, 16, between the inside surface of the sides, 5, of the housing and the outside surfaces of the back-wings, 15. Said channel, 16, is sized to receive the thickness of the top-lips, 13, of the hollow mullion post, 10, when engaged. The back, 7, of the housing is also shaped so that the back bottom-lips, 17, fit into the back of the mullion post, 10. The extensions of the back-wings, 15, which are below the front bottom-lips, 12, of the front, 6, and sides, 5, are sufficient to allow for holes, 18, to receive a pin, 3, which pivots the lever bar, 2, which will be described later. The holes, 18, are below sides, 5, and are positioned to be covered by the top of the mullion post, 10, when it is engaged, but to be accessible when the housing, 1 a, is separated from the mullion post, I0. The back, 7, has an opening, 19, above the line of the joint, 11, of the housing, 1a, and the mullion post, 10, to permit access to the bottom of the lever bar, 2, through opening, 20, in the back of the lever bar, 21, when the housing, 1a, containing the lever bar, 2, is engaged with a mullion post, 10 so that it may be moved to the disengage position by use of a simple article such as a rod, shaft of a screw driver, handle of a pliers or even a writing instrument such as a pen or pencil, thereby allowing for the easy removal of the mullion post.
The lever bar, 2, is shaped to fit snugly within the housing, 1a. The lever bar, 2, is secured in the rear of the housing which faces the inside of the doors, by a pivot pin, 3, which is inserted into the two complimentary holes, 18, provided in the back-wings, 15, and the corresponding holes (not shown in FIG. 3) in the sides, 22, of the lever bar, 2. The back, 21, of the lever bar, 2, has an opening, 20, which is accessible through an opening, 19, in the back of the housing, 7, which openings create a passage through the housing and the underside of the lever bar for use of the disengaging tool. The top, 23, of the lever bar, 2, is flat so that when depressed, the top, 23, flat surface of the lever bar, 2, meets flush with the top inside surface of the housing, 1a. The two sides, 22, of the lever bar, 2, have saddle shaped cut-outs, 24. These saddle shaped cut-outs, 24, are shaped to allow for the removal of the mullion post, 10, to be raised high enough so that the mullion post, 10, will clear the floor base plate, 30, and its retaining protrusions, 33, (not shown in FIG. 3) when being disengaged. The front, 25, of the lever bar, 2, has a top-lip and two sidelips (not shown in FIG. 3) which are contoured so that when in the locked position a cam action is created which tightens and locks the engaged mullion post, 10, in a fixed position.
DETAILED DESCRIPTION OF THE INVENTION
Referring to FIGS. 1 through 12
FIG. 1 illustrates an elevation view of a double doorway viewed from the inside having swinging doors, 28, mounted within a door frame in closed position, having a door frame header, 26, door frame sides, 27, swing doors, 28, fitted with panic rim hardware, 29, and showing the removable mullion, 10, between the doors fitted onto a base plate, 30, and its retaining protrusions, 33, and locked in place at the top by the mullion latch, 1, thereby locking the mullion post at both the top and bottom of the door frame.
FIG. 2 illustrates an expanded elevation view from inside of the swinging doors, 28, showing the mullion latch housing, 1, secured in the door frame header, 26, by screws, 32, or other attaching means. The openings, 19 and 20, are shown exposed to illustrate the ease and accessibility for disengaging and removing the mullion post, 10.
FIG. 2a illustrates an expanded elevation view from inside of the swinging doors, 28, showing the floor plate, 30, and its retaining protrusions, 33. The floor plate, 30, is secured to the floor by screws or other attaching means (not shown). The retaining protrusions, 33, are of a sufficient height to engage the mullion post, 10, securely in position when it is in the installed vertical position, but not so high as to inhibit the removal of the mullion post, 10. In general the height of the retaining protrusions, 33, should be slightly less than the depth of the saddle cut-outs, 24, in the lever bar, 2. Since the retaining protrusions, 33, will be exposed when the mullion post, 10, is removed to make way for the passage of equipment, furniture, and the like through the open double door frame, it is preferred to maintain the retaining protrusions, 33, in a low profile height.
FIG. 3 is an isometric view of the mullion latch, 1, of this invention, which has been described in detail in the BRIEF DESCRIPTION OF THE INVENTION, it shows the mullion latch housing, 1, engaged with a fragmentary portion of the upper part of a mullion post, 10, having a cutout of the top, 4, and side, 5, of the housing to show opening 19, in the back of the lever bar, 21, and a cut out of the back of the mullion post, 10, to show the back of the housing, 7, having opening, 20, which opening allows for the insertion of a disengaging device.
FIG. 3a is an isometric view of the cover, 34, which may be made of metal, plastic or other material. The cover, 34, has a back, 35, and sides, 36, and a lug, 37. The lug, 37, plugs into the opening, 19. The back, 35 of the cover, 34, rests on the back lip, 13, of the mullion post, 10, and the sides, 36, fit into the channel, 16, and cover the back portion of the back wings, 15, thereby covering the back, 7, of the exposed portions of the housing and the back portion of the sides which are exposed to give the appearance of a continuous mullion post.
FIG. 3b is an isometric view of the inside of the cover showing the disengaging device attached to the inside back of the cover. In this embodiment of my invention, the lug, 37, which retains the cover in place, is not required. The cover is fitted with the disengaging device by simply attaching a rod or bar, to the inside back of the cover. The cover is kept in place by the weight of the disengaging device which passes through the openings, 20 and 19, and resides inside the mullion latch, 1, when not in use. The disengaging device should be of sufficient length to reach the bottom front of the lever bar, 25, and of sufficient strength to lift the lever bar, 2, when leveraged or triggered. The rod, 31, should be set at a downward angle so that its length is parallel or somewhat lower than parallel, to the angle of the top of the lever bar, 23, when it is in the engaged position, thereby allowing for the free movement of the lever bar, 2.
FIGS. 4, 5 and 6 are sectional side, back and bottom views, respectively, in general alignment with each other, showing the detail of the mullion latch housing, 1a, and lever bar, 2, mounted on the top of a fragmentary portion of the upper part of a mullion post, 10.
FIG. 4, the sectional side view of the mullion latch of this invention, illustrates the detail of the mullion latch, 1, with openings, 19 and 20, to allow for the insertion of a disengaging tool for release of the latch bar, 2, when in the engaged position. It should be noted that the front surface of the lever bar, 25, tightly engages the inside surfaces of both the front of the housing, 6, and the top of the mullion post, 10, thereby providing a secure solid engagement, or locked position, so that there is no movement of the installed mullion post, 10, even when the swinging doors are slammed or by equipment bumping the mullion post when passing through. This locked position is provided for by the position of the pivot pin, 3, so that it provides a cam like action at the front surface, 25, of the lever bar, 2. Furthermore, by positioning the pivot pin, 3, close to the back of the housing, 7, the weight of the lever bar, 2, is concentrated in front of the pivot pin, 3, in the locked position, to provide the locking action without using a spring mechanism. FIG. 4 also shows the top of the mullion post, 10, and the top lip, 13, of the mullion post, 10, and bottom lip of the housings front and sides, 12, forming joint, 11, which is a loose fitting joint, between the bottom lip, 12, of the front of the housing, 1, and the top lip, 13, of the mullion post, 10. By this arrangement the mullion post, 10, is prevented from being raised and is immobilized in the vertical position.
FIG. 5 which is a back view of FIG. 4 which shows the detail of the mullion latch housing, 1a. FIG. 5 also illustrates that the back of the housing, 7, with opening ,20, and back wings, 15, also conform in size and shape to the inside of the mullion post, 10, but in a manner that leaves a space between back wings, 15, and housing sides, 5, creating channel, 16, for the top of the mullion post, 10, to slip into.
FIG. 6 which is a bottom view of FIG. 4 shows the detail of the mullion latch housing, 1a, and illustrates the shape of the back wings, 15, and front wings, 8. Also shown is the shape and width of the lever bar, 2, within back wings, 15, and also showing opening, 20. This view also shows the channel, 16, which is between the housing sides, 5 and back wings, 15. FIG. 6 also illustrates that the front of the housing, 6, and front wings, 8, conform to the size and shape of the mullion post, 10.
FIGS. 7, 8 and 9 are sectional side views of the mullion latch including the housing and latch bar showing the progressive operating stages of the mullion latch bar when removing the mullion from its installed position. The installation mode is essentially the reverse of the operation stages shown.
FIG. 7 shows the mullion latch, 1, and mullion post, 10, in the installed position. The lever bar, 2, is in the down position, showing the tight fit and locked position between the front of the lever bar, 25, and the back surface of the extension of the housing, 14, and the inside surface of the mullion post, 10, thereby firmly securing the mullion post, 10, in the vertical position. FIG. 7 also shows a disengaging device, a rod, 44, in position to release lever bar, 2, from the engaged position.
FIG. 8 shows the lever bar, 2, in the raised position, showing that the locked position between the front of the lever bar, 25, and the inside surfaces of the front, 6, of the housing and the inside surface of the mullion post, 10, has been unlocked. This is accomplished by simply tripping rod, 44, to its downward position. This unlocking allows the mullion post, 10, to be backed out of the mullion latch, 1, while the bottom of the mullion post, 10, is still partially engaged in the floor plate, 30. (FIG. 1 and FIG. 2a, show the bottom of the mullion post, 0, and the floor plate, 30, in the engaged position.) The unlocking of the top of the mullion post, 10, from the mullion latch, 1, is allowed for by the saddle cut-outs, 24, which permit the top of the mullion post, 10, to be raised into the saddle cut-out spaces, when the mullion post, 10, is lifted to disengage it from the floor plate, 30, and its retaining protrusions, 33.
FIG. 9 shows the lever bar, 2, still in the raised position with the mullion post, 10, being lowered so that the top lip, 13, is moved downward out of the mullion latch, 1, thus permitting easy removal of the mullion post, 10, from the door frame, by one person. (FIG. 1 and FIG. 2a, show the bottom of the mullion post, 10, and the floor plate, 30, in the engaged position, maintained in place by retaining protrusions, 33).
It should be noted that the pivot pin, 3, is positioned below the bottom lip, 12, of the housing front and at the back of the lever bar, 2. This positioning not only permits a cam like action at the front surface, 25, of the lever bar, 2, that locks in the mullion post, 10, but also allows for the mullion post, 10, to be easily installed by one person. From FIGS. 4, 5, and 6, it can be seen that the weight of the lever bar, 2, is concentrated in front of the pivot pin, 3, and because of its free swinging action is readily raised by the top of the mullion post, 10, when the mullion post, 10, is lifted into the installed position. When the mullion post, 10, is in the vertical position, the weight of the free swinging lever bar, 2, positions itself in the locked position, and it is not necessary to touch the latch bar, 2, during installation of the mullion post, 10, to the vertical position. The channel, 16, which is located between the back wings, 15, and housing sides, 5, allows for the mullion post, 10, when in the engaged position, to cover the pivot pin, 3, and complimentary holes, 18, in the extensions of the back wings, thereby hiding them from exposure in the installed position. The function of channel, 16, is to receive the top lips, 13, of the mullion post, 10, when being installed, so that the top lips, 13, of the mullion post, 10, may engage the bottom lips, 12, of the housing front, 6, and wings, 8, thereby providing a flush fit and support between the mullion post, 10, and the mullion latch, 1, of this invention.
FIGS. 10, 11 and 12 are isometric views of three different mullion posts that are in commercial use and showing adapters of this invention for retrofitting the mullion posts to employ the mullion latch of this invention.
FIG. 10 shows the adapter, 39, in line with one of the more common commercially installed movable mullion posts, 38. In accordance with this invention the adapter, 39, includes an insert, 40, shaped to fit snugly into the hollow core space, 41, of the mullion post, 38. The length of the insert, 40, is sufficient to slip into the hollow core space, 41, of the mullion post, 38, to form a stabilized connection between the surfaces of the parts in contact with each other. It is preferred that all the surfaces of the hollow core space, 41, of mullion post, 38, be in contact with all the outside surfaces of the insert, 40; however, it is only necessary for enough of those surfaces to be in close enough contact to provide a snug and stabilized fit. The adapter, 39, also includes a top portion, 42, which has a hollow core space, 43, that is shaped and sized to conform and fit the rectangular shape of the mullion latch, 1, of this invention, which conforms to the shape of the standard rectangular mullion post, 10, used in describing this invention. The top portion, 42, of the adapter, 39, is of a length so that it may be engaged into the mullion latch, 1, of this invention, and it may be made from a cut-off piece of a standard mullion post because it will be engaged in the mullion latch, 1, in the same manner as that described in connection with FIGS. 7, 8, and 9 for installing or removing the mullion post, 10. In order to use the adapter, 39, of this invention with an existing mullion post, 38, to retrofit the installation in accordance with this invention, a piece of the top of the mullion post, 38, is cut off so that the mullion post, 38, will match the length between the floor plate, 30, and the front lip, 12, of the mullion latch, 1. Accordingly, by cutting off a piece of the top of the mullion post, rather than from the bottom, the fittings for the panic rim locking mechanism are in the same height and position from the floor in the retrofitted mullion post as they were in the original mullion post, thereby obviating any changes in the location of such hardware, and further, the existing floor plate and retaining protrusions may be used as is. The retrofitted mullion post employing the adapter of this invention is installed and removed in the same manner described herein, as for example in connection with FIGS. 7, 8, and 9. and may be readily inserted and removed from the door frame, as many times as desired, realizing the advantages and objectives of this invention. The mullion latch, 1, of this invention is capable of being employed with various shaped movable mullion posts, 38, already installed and in use in existing structures through out the world, as is further exemplified in the following Figures.
FIGS. 11 and 12 show the shapes of other movable mullion posts, 38, in commercial use that may be retrofit, by the retrofit assembly kit provided in accordance with this invention All that is required to retrofit an existing movable mullion post, to employ the mullion latch of this invention, is to employ an adapter, 39, having an insert, such as, 40, which conforms in shape and contour to the cross section of the hollow core in the movable mullion post, 38, and which also has a top portion, 41, conforming in shape to the mullion latch of this invention. Thus, in accordance with the foregoing disclosure, the retrofit assembly kit of this invention comprises a mullion latch and an adapter; a cover for the lever bar opening and a hollow core mullion post also may be included.
It should be understood that FIGS. 10, 11 and 12 show an adapter, 39, which has a top portion, 42, which is the preferred rectangular shape, which happens to be one of the more prevalent shapes for removable mullion posts currently in commercial use. Further, it should be understood that this invention is also applicable to converting permanently installed mullion posts to become removable mullion posts. For example, in those installations where the mullion post is welded to the double door frame header, all that is required to convert it to a removable mullion post in accordance with this invention is to cut out the permanently installed mullion post at the header and extract the bottom of the mullion post from the floor. The mullion latch of this invention is installed in the header, and the floor plate with its retaining protrusions are installed beneath it on the floor, thereby allowing for a removable mullion post to be engaged in accordance with this invention. Double door frame assemblies that are hollow core and made of metals such as iron, steel, aluminium, or reinforced plastics and the like may be suitably used with this invention. Obviously, and with out departing from the intent and scope of my invention, the mullion latch of this invention may be made to conform in shape and cross section with any of the cross sections of the other shapes of mullion posts in use, such as those shown in FIGS. 10, 11, and 12, and which are given as examples, and still other cross section shapes of mullion posts, not shown. In such cases all that is necessary is to employ a shape or cross section of an adapter insert, 40, to conform and compliment each other so they fit together.
The means employed for disengaging the lever bar when in the engaged position, may be of any type such as the rod, 31, shown in the Figures. Alternatively, any device may be employed such as the shaft of a screw driver, the handle of a pliers, a metal bar, or a pencil or pen, which is of sufficient strength and length to disengage the lever bar from its secured position, when triggered or levered. The length of the disengaging device employed should allow it to reach the underside of the front of the lever bar when passed through the openings in the backs of the housing and lever bar and still be long enough to protrude out side the openings to allow for triggering or levering it to release the lever bar from the engaged position. The shortest length employed should allow the disengaging device to reach beyond the center of the saddle shaped cut-outs, 24, and extend out of opening, 19, sufficiently to allow for triggering or levering the exposed end of the device. The disengaging device may be attached to the cover, as described earlier with reference to FIG. 3b, thereby providing a unitary system and all the components for one person uninstalling the removable mullion post.
The openings, 19 and 20, may be of various sizes and shapes. Shapes of the openings may be square, rectangular, circular, oval, among other geometric shapes. All that is required is that the shape of the openings be substantially in line with each other to create a passage through the housing and underside of the lever bar to allow for the disengaging device to be able to be inserted through the passage in a manner which permits the disengagement of the lever bar from the locked position when it is desired to remove the mullion post. The two openings are positioned on the back of the lever bar and the back of the housing thereby allowing the pass through of the disengaging device to the release position on the bottom of the lever bar, as described earlier.
Although I have exemplified my invention using preferred embodiments thereof, it is understood that departures may be made therefrom within the scope of my invention, which is not limited to the details disclosed herein, but is to be accorded the full scope of the appended claims so as to embrace any and all equivalents. | A mullion latch is provided that will firmly secure a mullion post and yet permit the mullion post to be readily removable and reinstallable and which provides a tamper proof and secure vandal resistant mullion latch and post which is easy to install and remove. The mullion latch is used in conjunction with a double door opening that is designed to accommodate two single doors making use of the mullion post for their locking mechanisms, such as panic rim devices. Adapters are provided which may be used with the mullion latch in combination with a variety of mullion shapes, extruded or otherwise, that are employed in double door mullion assemblies, thereby negating any need to replace existing mullion posts when being adapted to employ the mullion latch. An assembly kit is provided for retrofitting or adapting existing mullion posts to be readily removable and reinstallable which includes the mullion latch combined with an adapter for use with a variety of existing moveable hollow core mullion shapes. | 4 |
This is a continuation of co-pending application Ser. No. 663,712 filed on Oct. 22, 1984, now abandoned 2/12/87.
BACKGROUND OF THE INVENTION
This invention relates to a voltage converting circuit which outputs an intermediate level of power supply voltage and particularly to a voltage converting circuit which is suitable for use in a MIS type integrated circuit.
It is often required in a MIS type integrated circuit to use a constant voltage having an intermediate level with respect to the power supply voltage supplied from an external circuit. For instance, an intermediate level of, for example, 2.5 V is steadily applied to a common capacitor electrode incorporated into memory cells in a MIS type dynamic random access memory operative under a power supply voltage of 5 V.
The intermediate level is obtained easily using a resistance dividing circuit as shown on FIG. 1. In this figure, resistors R 1 , R 2 divide the power supply voltage V cc in order to obtain an intermediate voltage V cc ' to be provided to a load circuit L. For a sufficiently low load current, when R 1 =R 2 , then V cc '=V cc /2. However, when a load circuit L consumes a current that is sufficiently high, such a relation is not maintained. Moreover, in this example, the resistors R 1 , R 2 are connected in series between the power source V cc of +5 V and the power source V ss of 0 V, a current always flows from V cc to V ss , and thereby a large amount of power is consumed. This is one disadvantage of this circuit. Such power consumption can be reduced by making large the resistors R 1 , R 2 . However, if a resistance value is large, the above change in the voltage V cc ' at node N1 due to a load current becomes large.
The circuit shown in FIG. 2 is effective for reducing power consumption and fluctuation of the load voltage V cc ' due to a change of the load current. In this circuit, a divided voltage of power source V cc obtained through the resistors R 1 , R 2 is given to the gate of a MIS transistor Q 1 and an output of said transistor Q 1 is applied to the load circuit L. Q 1 constitutes an output transistor of low output impedance. Therefore, a load current flows through the drain and source of transistor Q 1 but does not flow into the voltage dividing circuit R 1 , R 2 . There is no change of load voltage V cc ' and, since the dividing circuit only gives a voltage to the gate of the MIS transistor Q 1 , the circuit is allowed to have a high resistance value, thus resulting in less power consumption. Because of the relation V N -V th =V cc ' between the voltage V N of node N 1 and load voltage V cc ' , when V cc '=V cc /2 is required, V N is selected to have a value satisfying the relation, V N =V th +V cc /2. V th indicates the gate threshold voltage of the MIS transistor Q 1 .
However, this circuit has a problem in that a threshold voltage V th of the transistor Q 1 directly affects a load voltage V cc ' and V th changes in accordance with the integration circuit manufacturing process, whereby the load voltage V cc ' fluctuates for each product.
Namely, it is well known that a resistance ratio of two resistors in an integrated circuit has only a small error, although there are changes of V th depending on the manufacturing process. For example, it is easy to ensure that an error of resistance value ratio is as small as 1% or less. Therefore, a voltage V N of node N 1 can be set accurately. Meanwhile, the gate threshold voltage of a MIS transistor is easily affected by a process fluctuation, and an error as small as 0.2 V can easily be generated. This error means, for example, that an error of about 10% easily occurs in the circuit for generating an output voltage V cc ' of 2.5 V.
SUMMARY OF THE INVENTION
An object of this invention is to provide a voltage converting circuit which outputs an intermediate level of power source voltage.
Another object of this invention is to provide a voltage converting circuit which consumes less power.
Yet another object of this invention is to provide a voltage converting circuit comprising an output MIS transistor which gives a small output impedance.
A further object of this invention is to prevent an output voltage from being affected by a variation of the threshold voltage V th caused by a fluctuation in the manufacturing process for output MIS transistors of voltage converting circuits.
In accordance with the present invention, a voltage converting circuit is provided for receiving a power source voltage and providing a constant voltage having the level of a predetermined porportional division of said power source voltage, comprising:
an output MIS transistor for outputting said constant voltage, with the MIS transistor having a gate which receives a gate control voltage; and
a gate control means for providing said gate of said MIS transistor with said gate control voltage, comprising an impedance means connected to receive said power source voltage for providing said predetermined proportional division, and compensating means having at least one compensation MIS transistor connected to said impedance means, for compensating the gate control voltage for the gate threshold voltage of said output MIS transistor to provide said constant voltage corresponding to said predetermined proportional division irrespective of variation of said gate threshold voltage.
BRIEF DESCRIPTION OF THE DRAWINGS
The above and other objects and advantages of the present invention will be more apparent from the following description of the preferred embodiments with reference to the accompanying drawings, wherein:
FIG. 1 is a circuit diagram of a voltage converting circuit in the prior art;
FIG. 2 is a schematic diagram of the other voltage converting circuit in the prior art;
FIG. 3 is a schematic diagram of a voltage converting circuit in an embodiment of this invention;
FIG. 4 is a schematic diagram of a voltage converting circuit in another embodiment of this invention;
FIG. 5 is a schematic diagram of a voltage converting circuit in yet another embodiment of this invention;
FIG. 6 is a schematic diagram of a voltage converting circuit in a further embodiment of this invention;
FIGS. 7(a) and (b) are respective the graphs which show the change in time of the converted voltage output after the power source is turned ON in the circuits of the prior art and of the embodiments of this invention; and
FIG. 8 is a schematic diagram of a voltage converting circuit in still a further embodiment of this invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 3 shows an embodiment of this invention. From FIG. 1 to FIG. 8, the same portions as those in FIG. 1 and FIG. 2 are given the same symbols for convenience of description. In comparison with the circuit of the prior art as shown in FIG. 2, the circuit of FIG. 3 is different therefrom in such a point that the MIS transistors Q 2 , Q 3 are inserted into the voltage dividing circuit (gate voltage control circuit). In the circuit of FIG. 3, a pair of N channel MIS transistors Q 2 , Q 3 are connected in series to the resistor elements R 1 and R 2 which give a voltage dividing ratio. A divided output from the series circuit of resistor elements R 1 , R 2 and MIS transistors Q 2 , Q 3 is given at the node N 1 to the gate of the output N channel MIS transistor Q 1 . The transistors Q 2 , Q 3 are provided for compensating its gate threshold voltage, and the number of transistors depends on the voltage dividing ratio. The circuit of FIG. 3 is provided for outputting a voltage of V cc /2 and two transistors Q 2 and Q 3 are required in this case. Said circuit of FIG. 3 operates normally when a voltage of the power source voltage supply line is higher than the normal voltage V cc /2 to be output. In this case, the voltage of node N 2 is V th , the voltage of node N 3 is 2×V th . When R 1 =R 2 , the voltage of node N 1 is indicated by (V cc -2V th )/2+2V th =V cc /2+V th . Since the transistors Q 1 , Q 3 are formed by the same process on a semiconductor substrate, these transistors can be considered to have the same threshold voltage. When the node N 1 has the above voltage, a load voltage V cc ' is V cc /2, which is lower than the above voltage by V th . Thereby, a voltage V cc ' irrespective of the threshold voltage of a transistor can be supplied to the load L.
FIG. 4 is a second embodiment of this invention. The circuit of FIG. 3 is based on the assumption that the load L always receives an input current through the transistor Q 1 (a current flows through V cc -Q 1 -L-V ss ) and that a current does not flow out from the load L toward the source of the transistor Q 1 . However the circuit of FIG. 4 can operate properly even if current flows out from the load L. In this circuit, the circuit portion formed by R 1 , R 2 , Q 3 , Q 2 is the same as that in FIG. 3, a load voltage V cc ' is held thereby to V cc /2, irrespective of V th . The MIS transistors Q 4 , Q 5 , Q 6 resistors R 3 , R 4 form a circuit which holds the load voltage V cc ' to V cc /2 in such a case where a current flows into the power supply V ss through the transistor Q 4 from the load L. Here, Q 4 , Q 5 , Q 6 are P channel transistors. Namely, the voltage of node N 6 is V cc -V thp , the voltage of node N 5 is V cc -2V thp and the voltage of node N 4 is (V cc -2V thp )/2=V cc /2-V thp when R 3 =R 4 . V thp is the gate threshold voltage of the p channel transistor Q 4 . Since a voltage of node N 4 is lower than V cc ' by V th of Q 4 , V cc ' becomes V cc /2. In the circuit of FIG. 4, a load voltage can be set constant irrespective of a load voltage V th , in either case where a current flows into the load or a current flows out from the load.
It is desirable in actual design of the circuit of FIG. 4 to assure the avoidance of a steady current in the series circuit of transistors Q 1 and Q 4 by providing a small difference between the voltage dividing ratio of the resistors R 1 , R 2 and the voltage dividing ratio of the resistors R 3 , R 4 . For example, the voltage of node N 1 should advantageously be V cc /2+V th minus several 10 mV and the voltage of node N 4 should be V cc /2-V thp plus several 10 mV. Thereby, when the output voltage V cc ' is V cc /2, both output transistors Q 1 , Q 4 are set to the cut-off condition. IF the output voltage V cc ' rises or drops, the output transistors Q 1 or Q 4 become selectively ON and suppress the change of voltage described above.
FIG. 5 and FIG. 6 show the third and fourth embodiments of this invention. The former holds a load voltage V cc ' to V cc /3, while the latter to 2V cc /3. Namely, since the voltage of node N 7 is 3V th and the resistance values of resistors R 1 , R 2 are selected in such a relation as R 1 =2R 2 in FIG. 5, the voltage of node N 1 becomes equal to (V cc -3V th )/3+3V th =V cc /3+2V th , and the load voltage V cc ' is lower than this voltage level by 2V th due to the voltage drop across transistors Q 8 and Q 1 thus becoming equal to V cc /3. In FIG. 6, the voltage of node N 7 is 3V th , the voltage of node N 1 is 2(V cc -3V th )/3+3V th =2V cc /3+ V th when 2R 1 =R 2 , and the load voltage V cc ' is lower than this voltage by V th , becoming equal to 2V cc /3.
In general, the load voltage of V cc '=mV cc /n can be obtained by using n transistors as the transistors Q 2 , Q 3 , . . . to be inserted in series with the resistance voltage dividing circuit, of the gate voltage control circuit and (n-m-1) transistors as the transistors Q 8 . . . to be inserted into the gate circuit of the output transistor Q 1 , and by setting a resistance ratio R 2 /(R 1 +R 2 ) to m/n. Thereby, a variety of load voltages V cc ' which are not affected by V th can be obtained. In the above, m and n are integers for which m<n.
When the resistance value is made large in order to reduce power consumption in the resistance voltage dividing circuit, the time constant becomes large and the rising edge of the load voltage becomes gentle as shown in FIG. 7(a). In case a transistor Q 1 is used as in the case of FIG. 3, the load voltage V cc ' quickly rises as shown in FIG. 7(b) and, when the power supply becomes ON, operation can be started immediately.
In the circuit of FIG. 3, the resistor R 2 may be shifted, for example, to the location between Q 3 and V ss from the location indicated. The alternate location for the resistor R 2 is indicated by the resistor R 2 ', shown with the dotted line in the lower left corner of FIG. 3. In this case, the same result can also be obtained. Moreover, this method is superior in such a point that each transistor Q 1 , Q 2 , or Q 3 receives a similar back gate bias effect on its own V th , since the source voltage of Q 2 , Q 3 rises up to a value close to that of Q 1 and, thereby, V th of Q 2 and Q 3 becomes equal to that of Q 1 .
FIG. 8 shows an embodiment where the resistors R 1 , R 2 in FIG. 3 are replaced by depletion transistors T 1 , T n , T 1 ' T n '. The same transistors and the same nodes are indicated by the same symbols. In general, a resistance of the polysilicon layer or diffusion layer used in a MIS dynamic memory is as small as several 10 ohms/square. If it is desired to obtain a resistance of several 100 k-ohm as required for the resistors R 1 , R 2 by using these resistance layers, an area of several hundreds of thousand μ 2 becomes necessary. In order to avoid this, it is recommended to use one or a plurality of depletion transistors connected in series in place of resistors. Thereby, a current can be reduced using a small area. | A voltage converting circuit has an output MIS transistor which gives a low output impedance and outputs an intermediate level of power source voltage. The output level is set with a high accuracy through a voltage dividing ratio determined by an impedance element. This impedance element is connected with a compensating MIS transistor to compensate for variations of the gate threshold voltage caused by the manufacturing process. | 7 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a continuation of U.S. application Ser. No. 13/646,277 filed on Oct. 5, 2012, which claims the benefit of U.S. Provisional Application No. 61/543,663, filed on Oct. 5, 2011, and U.S. Provisional Application No. 61/606,031, filed on Mar. 2, 2012, and U.S. Provisional Application No. 61/610,805, filed on Mar. 14, 2012. Each of these four applications is hereby incorporated by reference in its entirety.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
Not Applicable
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to offshore drilling and production platforms. More particularly, it relates to a method and apparatus for drilling a plurality of wells at a single platform (or vessel) location and installing production risers on those wells.
2. Description of the Related Art Including Information Disclosed Under 37 CFR 1.97 and 1.98
Both tension leg platforms (TLP's) and semi-submersible floating vessels (“semis”) can be used for offshore drilling and production operations.
A tension leg platform (TLP) is a vertically moored floating structure typically used for the offshore production of oil and/or gas, and is particularly suited for water depths greater than about 1000 ft.
The platform is permanently moored by tethers or tendons grouped at each of the structure's corners. A group of tethers is called a tension leg. The tethers have relatively high axial stiffness (low elasticity) such that virtually all vertical motion of the platform is eliminated. This allows the platform to have the production wellheads on deck (connected directly to the subsea wells by rigid risers), instead of on the seafloor. This feature enables less expensive well completions and allows better control over the production from the oil or gas reservoir.
A semi-submersible is a particular type of floating vessel that is supported primarily on large pontoon-like structures that are submerged below the sea surface. The operating decks are elevated perhaps 100 or more feet above the pontoons on large steel columns. This design has the advantage of submerging most of the area of components in contact with the sea thereby minimizing loading from wind, waves and currents. Semi-submersibles can operate in a wide range of water depths, including deep water. The unit may stay on location using dynamic positioning (DP) and/or be anchored by means of catenary mooring lines terminating in piles or anchors in the seafloor. Semi-submersibles can be used for drilling, workover operations, and production platforms, depending on the equipment with which they are equipped. When fitted with a drilling package, they are typically called semi-submersible drilling rigs.
The DeepDraftSemi® vessel offered by SBM Offshore, Inc. (Houston, Tex.) is a semi-submersible fitted with oil and gas production facilities that is suitable for use in ultra-deep water conditions. The unit is designed to optimize vessel motions to accommodate steel catenary risers (SCRs).
BRIEF SUMMARY OF THE INVENTION
A floating, offshore drilling and/or production platform is equipped with a rail-mounted transport system that can be positioned at a plurality of selected positions over the well bay of the vessel. The transport system can move a drilling riser with a drilling riser tensioner system and a blowout preventer from one drilling location to another without removing them from the well bay of the vessel. Using the transport system, the drilling riser is lifted just clear of a first well head and positioned over an adjacent, second well head using guidelines. The transport system may then move the upper end of the drilling riser (together with its attached tensioner and BOP) to a second drilling location. A dummy wellhead may be provided on the seafloor in order to secure the lower end of the drilling riser without removing it from the sea while production risers are being installed.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING(S)
FIG. 1 is a perspective view of an isolated well bay on an offshore drilling platform according to one particular embodiment of the invention that provides for 27 production riser tensioners and up to nine locations of a moveable drilling riser tensioner and blowout preventer.
FIG. 2 shows the well bay illustrated in FIG. 1 installed in the lower deck (“production deck”) of a TLP.
FIGS. 3A-3C show both a production riser tensioner and surface tree assembly as well as a drilling riser tension joint, drilling riser tensioner and blowout preventer assembly on a transport trolley according to the invention. FIG. 3A is a top view of the two assemblies supported on a topside deck wellbay beam according to the invention. FIG. 3B is a side view of the two assemblies supported on a topside deck wellbay beam according to the invention. FIG. 3C is an end view of the drilling riser tension joint, drilling riser tensioner and blowout preventer assembly on the transport trolley.
FIGS. 4A-4D show various views of an adapter frame in the retracted (drilling) position within a transport trolley according to the invention. FIG. 4A is an isometric view of the adapter frame in the retracted position. FIG. 4B is a top view of the adapter frame in the retracted position. FIG. 4C is an end view of the adapter frame in the retracted position. FIG. 4D is a side view of the adapter frame in the retracted position.
FIGS. 5A-5D show various views of an adapter frame in the extended (transfer) position within a transport trolley according to the invention. FIG. 5A is an isometric view of the adapter frame in the extended position. FIG. 5B is a top view of the adapter frame in the extended position. FIG. 5C is an end view of the adapter frame in the extended position. FIG. 5D is a side view of the adapter frame in the extended position.
FIGS. 6A-6D show various views of a transport trolley according to the invention. FIG. 6A is an isometric view of the transport trolley. FIG. 6B is a top view of the transport trolley. FIG. 6C is an end view of the transport trolley. FIG. 6D is a side view of the transport trolley.
FIGS. 7A-7D show various views of an adaptor frame (or drilling riser support insert) according to the invention. FIG. 7A is an isometric view of the adaptor frame. FIG. 7B is a top view of the adaptor frame. FIG. 7C is an end view of the adaptor frame. FIG. 7D is a side view of the adaptor frame.
FIGS. 8A-8E illustrate the sequential steps used in transferring a drilling riser between adjacent wells on the seafloor in a method according to the invention. FIG. 8A is an illustration of Step 1 of the method. FIG. 8B is an illustration of Step 2 of the method. FIG. 8C is an illustration of Step 3 of the method. FIG. 8D is an illustration of Step 4 of the method. FIG. 8E is an illustration of Step 5 of the method.
DETAILED DESCRIPTION OF THE INVENTION
The invention may best be understood by reference to one particular preferred embodiment whose apparatus is illustrated in FIGS. 1-7 and an associated method of use is illustrated in FIG. 8 as a sequence of steps. The drawing figures outline general equipment and methodology for drilling multiple wells from a floating unit, and the installation of production risers, while minimizing or eliminating the need to retrieve the drilling riser when moving between wells.
The system shown is intended for use on a well pattern which is essentially rectangular in shape, but it should be understood that similar methodology could be adapted to well patterns of a more square shape or other patterns.
One particular feature of the system is a transfer trolley, which is suspended from the lower deck (the production deck) of the floating platform. The transfer trolley is set to run down the length of the well pattern. The position of the transfer trolley is held side to side by fixed rails, or similar, which may form part of the deck structure. The end-to-end position of the transfer trolley may be shifted using a rack-and-pinion arrangement with the pinion(s) turned by hydraulic motors or the like. The end-to-end position of the transfer trolley may be controlled by other means—for example by a pair of opposing winches used to translate the transfer trolley.
The transfer trolley may be used to transport the assembled drilling riser together with an associated tensioner and blowout preventer (BOP) between well bay positions.
The production deck (the lower deck) of the floating structure may contain discrete (separate) tensioners 42 for the near-vertical production risers. These tensioners may be arranged in a regular geometric pattern, as shown in FIG. 1 . It should be noted that the spacing of the well bay on the structure may be chosen to be consistent with the physical requirements to fit production tensioners, surface trees, connection jumpers, and other required equipment for drilling, production, work over and so forth. The wells may be spaced on the seafloor to provide access space as required for various seafloor activities related to drilling, production, etc. The seafloor and surface spacing may not necessarily be identical (due to different space requirements) but may be established in a way to minimize the offset angles between corresponding seafloor and surface locations.
Referring in particular to FIGS. 1 and 2 , the TLP includes provision for installation of a total of 27 riser tensioners in a 9-by-3 array of well slots 20 on the lower deck 82 of a TLP. The drilling riser is deployed only from the central of the three columns, with the ability to reach each of the 27 subsea well head locations from at least one of the nine positions within the central column. For certain well patterns, less than the full 9 central column positions may be needed to reach each of the wells on the seafloor. The central column may initially be open to allow translation of the hanging drilling riser to locations appropriate for reaching the well heads. Production risers in the two outer columns may be installed first, with tensioners 42 and surface trees 40 mounted on the lower deck (production deck) 82 . As additional risers are added, inserts may be placed in the central column to allow installation of production riser tensioners therein. Tree access platforms 16 may be provided in production deck structure 18 . FIG. 1 shows the outer columns with all production risers installed, a single production riser installed at one end of the central column, and the drilling riser 36 near the midpoint of the central column. FIG. 1 also shows a smaller BOP 28 (used for well completion) on a Production Riser Tensioner 42 (connected to production riser tension joint 44 ) in the outer row adjacent to the larger drilling BOP 26 , confirming adequate clearance between the two BOP's.
FIG. 2 shows the production deck 82 of a TLP equipped with a drilling riser transport system according to the invention viewed from the opposite end of the well bay as that shown in FIG. 1 and with the topsides structure (drilling deck) in place. The two winches 22 shown at the near end of the opening in the lower deck 82 are for the drilling riser guidelines 24 . This view also shows the routing of the production 10 , annulus 14 and control jumpers 12 for each of the surface trees. These jumpers are routed outward on the two outer columns of wells. The boxes 84 above the central (open) column represent the tie off locations for the central wells. Note that there is ample clearance for hook up of hard piping to the drilling BOP 26 .
FIG. 3B is a side view of a drilling riser assembly comprising drilling riser tension joint 36 , a drilling riser tensioner system 30 and a high-pressure blowout preventer (BOP) 26 supported in a drilling riser transfer system 32 according to the invention.
As shown in FIG. 3A (a top plan view), the support inserts for both the production tensioners 42 and drilling riser tensioner 30 may rest on brackets 38 extending outward from the main beams 64 along the edges of the opening in the lower deck. The drilling riser 36 may be moved by means of a transporter 32 which fits around the Drilling Riser Transport (DRT) support insert 66 and can lift it clear of the support brackets 38 .
Also shown in the top and side views of FIG. 3 are winches 22 for guide wire ropes 24 . Winches 22 may be constant tension winches. Guide wire rope 24 may be routed around sheave 86 and through openings in drilling riser tensioner 30 and hole 62 (see FIG. 6 ) in transport trolley 32 .
As illustrated in FIG. 4 , the transporter 32 may move the drilling riser assembly ( 26 + 30 + 36 in FIG. 3 ) on rails 34 ( FIG. 1 ) by means of a rack-and-pinion drive system, located on the edges of the opening in the lower deck. Racks 70 may be attached to well bay support beams 64 and/or tracks 72 and pinions 68 may be mounted on transport trolley 32 and connected to hydraulic drive motors 52 . The transporter may be supported by Hilman rollers 54 (Hilman Inc., Marlboro, N.J. 07746) resting on horizontal tracks 72 . As shown in FIG. 4 , the drive system of the illustrated embodiment uses four drive motors. In addition, the motion of the transporter may be controlled by guide rollers (not shown) reacting on the sides of the track on one or both sides of the opening in the lower deck.
In FIG. 4 , adaptor frame 66 is shown in the retracted position. The extended position of the adaptor frame 66 is shown in phantom in FIG. 4C and FIG. 4D . When in the retracted position, the adaptor frame 66 is supported by deck support brackets 38 and not (to any significant degree) by transport trolley 32 . It will be appreciated that the retracted position of adaptor frame 66 is that used during drilling operations. When in the retracted position, the reactive force of the drilling riser tensioner system 30 is transmitted to the deck structure 64 via deck support brackets 38 . The supports of transport trolley 32 (e.g., Hilman rollers 54 and support arms 88 ) are not exposed to the dynamic loads of heave compensation imposed by tensioner system 30 .
FIG. 5 is similar to FIG. 4 , but with adaptor frame 66 in the extended position. As shown in FIG. 5 , the DRT support insert 66 may be lifted relative to the transporter 32 by four hydraulic cylinders 60 , two on each side of the insert. The geometric shape of the support insert and the transporter may be such that overlap between the two parts provides guidance as the support insert rises, limiting lateral loads on the hydraulic cylinders.
Extending adapter frame 66 results in lifting the drilling riser assembly sufficiently to clear the wellhead on the seafloor to which is was connected. This permits the drilling riser assembly to be moved horizontally within the well bay without disconnecting either the drilling BOP 26 or the drilling riser tensioner system 30 . Moreover, the drilling riser itself may remain in the sea. In certain embodiments, a dummy wellhead may be provided on the seafloor for landing and securing the lower end of the drilling riser while production risers are run. This can help to prevent collisions between the risers.
FIG. 6 contains four views of a transport trolley 32 according to one embodiment of the invention— FIG. 6A is an isometric view, FIG. 6B is a top plan view, FIG. 6D is a side view and FIG. 6C is an end view. Adapter frame lift cylinders 60 are shown within transport trolley 32 . Also shown are openings 62 for guidelines 24 which may be sized to also permit passage of the remote ROV guide post tops (see FIG. 8 ).
FIG. 7 contains four views of an adapter frame 66 according to one embodiment of the invention— FIG. 7A is an isometric view, FIG. 7B is a top plan view, FIG. 7D is a side view and FIG. 7C is an end view. Adapter frame 66 has a central opening 67 with a perimeter rim 74 which may project into opening 67 . Rim (or flange) 74 may be sized and configured to fit drilling riser tensioner system 30 . Drilling riser tensioner system 30 is supported on rim 74 . Load brackets 80 are sized and configured to engage deck support brackets 38 . Lift extensions 78 are sized and configured to engage adapter frame lift cylinders 60 . In a system according to the invention, the static load of the drilling riser assembly is borne on lift extensions 78 when transport trolley 32 is moved horizontally but the static and dynamic loads are borne by load extensions 80 when the drilling riser is connected and tensioned by tensioner system 30 . As shown in FIG. 7 , load extensions 80 may be reinforced with gussets 90 .
Specific design parameters for one particular preferred embodiment of a drilling riser transport system according to the invention are:
The transporter 32 may be supported by four sets of Hillman rollers 54 . The top of the DRT support insert 66 is level with the top of the support rails when the transporter lift cylinders 60 are retracted. The DRT 30 fits within the inner opening 67 of the support insert 66 , and is supported by a ledge 74 around the perimeter of the opening. Lift of the DRT support insert 66 relative to the transporter 32 is sufficient to clear the well head and its associated guide posts. Maximum load carried by the DRT support insert 66 is carried through the brackets 80 . Static load only is carried by the transporter 32 during lift and movement of the drilling riser. The transporter 32 carries no load when the DRT support insert 66 is resting on the brackets 80 . The transporter may be driven by a rack 70 and pinion 68 system powered by hydraulic drive motors 52 .
As shown in the sequence illustrated in FIG. 8 , the transfer method according to the invention begins at Step 1 ( FIG. 8A ) with the drilling riser and its associated tieback connector attached to a home position wellhead. At Step 2 ( FIG. 8B ), the guidelines are slackened so that the ROV can unlock the upper section of the guideposts (“guide post tops”) and move them to the adjacent wellhead. If not already deployed, the guide arms may be folded down (using the ROV) and the guidelines reattached to the drilling riser by positioning the guidelines in the lower guide arms via gates in the guide arms. In Step 3 ( FIG. 8C ), the tieback is disconnected from the home position wellhead and lifted by extending the adapter frame lift cylinders 60 . This provides sufficient clearance to move the tieback connector from the home position wellhead to the adjacent wellhead by applying a selected amount of tension to the guidelines 24 using guide line winches 22 (which may be constant tension winches). The transporter 32 may concurrently move the drilling riser to the closest available drilling position over the target wellhead. The lower guide arms may be free to swivel around the tie back connector to align and connect with the guidelines and guideposts. The guide arms may be sized such that, in the folded position, they may pass through passageways in the drilling riser tensioner and openings 67 in drilling riser transfer trolley 32 . After full positioning tension is applied to the guidelines thereby realigning the tieback connector over the adjacent well (Step 4 ; FIG. 8D ), the drilling riser may be lowered (Step 5 ; FIG. 8E ) by retracting hydraulic lift cylinders 60 , and the tie back connector landed and locked on the adjacent wellhead.
Although particular embodiments of the present invention have been shown and described, they are not intended to limit what this patent covers. One skilled in the art will understand that various changes and modifications may be made without departing from the scope of the present invention as literally and equivalently covered by the following claims. | A floating, offshore drilling and/or production platform is equipped with a rail-mounted transport system that can be positioned at a plurality of selected positions over the well bay of the vessel. The transport system can move a drilling riser with a drilling riser tensioner system and a blowout preventer from one drilling location to another without removing them from the well bay of the vessel. Using the transport system, the drilling riser is lifted just clear of a first well head and positioned over an adjacent, second well head using guidelines. The transport system may then move the upper end of the drilling riser (together with its attached tensioner and BOP) to a second drilling location. A dummy wellhead may be provided on the seafloor in order to secure the lower end of the drilling riser without removing it from the sea while production risers are being installed. | 4 |
TECHNICAL FIELD
The present invention relates generally to semiconductor memory devices, and more particularly to virtual channel memories that can have a memory cell array that includes a number of memory cells arranged into one or more arrays and a register array that includes a number of registers arranged into a corresponding array(s).
BACKGROUND OF THE INVENTION
Semiconductor memory devices include dynamic random access memories (DRAMs). Recently, the mainstream use of DRAMs has shifted toward synchronous DRAMs (SDRAMs). A virtual channel SDRAM (VCSDRAM) has been proposed in Japanese Patent Application No. Hei 9-290233. VCSDRAMs can be desirable as they can further increase an access speed for a SDRAM.
A virtual channel memory, such as a VCSDRAM, can include a memory cell array having a number of memory cells, such as DRAM memory cells arranged in a row direction and a column direction. In addition, a virtual channel memory can also include a register array having registers arranged into a predetermined number of rows and a predetermined number of columns. The register array rows and columns can correspond to the rows and columns in the memory cell array. The register array can take the form of a static random access memory (SRAM) and have a cache function.
One particular type of system that can utilize DRAMs is a parallel processing system. A parallel processing system can include a number of central processing units (CPUs) and a number of controllers that are connected to bus lines. The bus lines are connected to a register array that is combined with a memory cell array. The register array can operate as a cache memory. In the parallel processing arrangement, one cache memory can be used by a plurality of CPUs and a plurality of controllers. Such an arrangement can lead to a more simplified system structure.
One particular application for a VCSDRAM is that of a graphic memory. A graphic memory can store image data. In many graphic memory operations, the same data (e.g., "0" or "1") is frequently written into or read from a large number of memory cells at the same time. One example of such an operation is when image data is reset. Accordingly, when a VCSDRAM is used as a graphic memory, the same data is frequently stored in the memory cell array and the register array. In a conventional approach, when the same data is to be written into a memory cell array and the register array, the write data will be written from external input/output pins to the memory cell array and the register array one by one. For example, if a register array includes registers arranged in an m×n array, data can be written into m×n memory cells. The same data must then be written into m×n registers of the register array. As a result, image reset operations can consume a considerable amount of time.
In light of the above, it would be desirable to provide a memory device that may be used with image processing that can reduce the period of time required for reading or writing data when an image is reset. It would also be desirable that such a memory device be a VCSDRAM.
SUMMARY OF THE INVENTION
In light of the above drawbacks, an object of the present invention is to provide a semiconductor memory device that may be used in image processing that can reduce the amount of time for a data read or write during an image reset operation. Such a semiconductor memory device can be a virtual channel synchronous dynamic random access memory device (VCSDRAM).
According to the present invention, one embodiment can include a semiconductor memory device having a memory cell array and a register array. The memory cell array can include a number of memory cells arranged into one or more arrays having rows and columns. The register array can include a number of registers arranged into an array having rows and columns that correspond to at least one portion of a memory cell array. The embodiment can further include a data writing means for writing data into a memory cell of a first column and a corresponding first register at the same time. The memory cell of the first column and corresponding first register can be connected to each other through a transfer bus line.
According to one aspect of the invention, when the same data value is to be written into a memory cell and a register, the data can be written to the memory cell and the register at the same time. This can result in reduced data write times.
According to another aspect of the invention, memory cells of the virtual channel memory can take a variety of forms. As just one example, the memory cells can include high-resistance load DRAM cells.
According to another aspect of the invention, registers of the virtual channel memory can take a variety of forms. As just one example, the registers can include static RAM (SRAM) cells.
According to one embodiment, data can be written into a memory cell of a first column and a corresponding register independently. Data can then be transferred between the memory cell of the first column and the corresponding first register. In this arrangement the degrees of freedom available for write operations are increased.
According to one embodiment, the data writing means may receive input data from external bus lines. The data writing means may include switching means that connect the external bus lines to transfer bus lines in response to an external signal.
According to one embodiment, the data writing means may include a write data producing means. In such an arrangement, the data writing means may include switching means that connect transfer bus lines to a predetermined power supply voltage in response to an external signal.
According to one embodiment, the data writing means can write internally generated data values to a memory cell in a first column and a corresponding register at the same time. This can result in faster transfer of data within the device.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block diagram illustrating a virtual channel memory according to a first embodiment.
FIG. 2 is a block diagram illustrating a virtual channel memory according to a second embodiment.
FIG. 3 is a schematic diagram of an alternate write data producing section that may be used in an embodiment.
FIG. 4 is a schematic diagram of an alternate data transfer section that may be used in an embodiment.
DETAILED DESCRIPTION OF THE EMBODIMENTS
Various embodiments of the present invention will now be described with reference to a number of drawings. FIG. 1 is a block diagram showing the structure of a virtual channel memory (such as a virtual channel synchronous dynamic random access memory, or VCSDRAM) according to a first embodiment. The virtual channel memory is designated by the general reference character 100, and is shown to include a memory cell array 102 and a register array 104. A memory cell array 102 can include a large number of memory cells, which are arranged in a row direction and column direction to form one or more arrays.
A register array 104 can include a number of "channel" registers (referred hereinafter as "channels"). In the particular arrangement of FIG. 1, the register array 104 includes channels arranged into "n" rows and "m" columns. Exemplary channels are identified in FIG. 1 as 106-11 to 106-1n and 106-m1 to 106-mn. The number of rows and columns of channels within the register array 104 can be related to the number of rows and columns in the memory cell array 102. For example, the memory cell array 102 can include i×n rows and j×m columns, where i and j are integers.
In one particular embodiment, the memory cells of memory cell array 102 can be dynamic random access memory (DRAM) cells. The channels (106-11 to 106-mn) of register array 104 can be static RAM (SRAM) cells.
Referring once again to FIG. 1, the n channels of each column in the register array 104 can be connected to corresponding data transfer buses by switches. In particular, channels 106-11 to 106-1n are coupled to data transfer bus 108-1T/108-1N by switches 110-11 to 110-1n, respectively. Channels 106-m1 to 106-mn are coupled to data transfer bus 108-mT/108-mN by switches 110-m1 to 110-mn, respectively.
Data transfer buses (108-1T/108-1N to 108-mT/108-mN) can be connected to digit lines by column switches. In the particular arrangement of FIG. 1, data transfer bus 1081T/108-1N is shown to be connected to digit line pair 112-1T/112-1N by column switch 114-1, and data transfer bus 108-mT/108-mN is shown to be connected to digit line pair 112mT/112-mN by column switch 114-m. Each column switch (114-1 to 114-m) can have the function of arbitrarily switching between a number of digit line pairs. In particular, such switching can occur between j such digit line pairs, where the number of columns in the memory cell array 102 includes j×m columns. The value j could be "4," as just one example.
FIG. 1 also includes a number of sense amplifiers (116-1 to 116-m) disposed between the memory cell array 102 and the digit line pairs (122-1T/112-1N to 112-nT/112-mN). Sense amplifiers (116-1 to 116-m) can amplify data, and may serve to transmit data between their corresponding digit line pairs (122-1T/112-1N to 112-nT/112-mN) and respective memory cells.
In the arrangement of FIG. 1, one end of the data transfer buses (108-1T/108-1N to 108-mT/108-mN) is coupled to a write data producing section 118. The particular write data producing section 118 of FIG. 1 is shown to include n-channel transistors 120-11/120-12 to 120-m1/120-m2 connected between the data transfer buses 108-1T/108-1N to 108-mT/108-mN and a GND potential. The gates of transistors 120-11 to 120-m1 receive a data write signal DS1. The drains of transistors 120-11 to 120-m1 are connected to one line of a corresponding data transfer bus 108-1T to 108-mT. The sources of transistors 120-11 to 120-m1 are connected to a voltage GND. The gates of transistors 120-12 to 120-m2 receive a data write signal DS2. The drains of transistors 120-12 to 120-m2 are connected the other line of a corresponding data transfer bus 108-1N to 108-mN. The sources of transistors 120-12 to 120-m2 are connected to the voltage GND. One skilled in the art would recognize that a transistor can provide a controllable impedance path between its respective source and drain. Such a path may include high and low impedance states. Further, the n-channel transistors illustrated show but one example of an insulated gate field effect transistor (IGFET) that may be used in the particular embodiment.
In FIG. 1, a data transfer signal DTS is received by column switches (114-1 to 114-m). In this arrangement, column switches (114-1 to 114-m) can be turned on or off together. Each row of switches within the register array 104 receives a channel select signal. In particular, switches 110-11 to 110-m1 receive the channel select signal CHS1, and switches 110-1n to 110-mn receive the channel select signal CHSn. In this arrangement, the switches of each row in the register array 104 can be turned on or off together.
According to the particular embodiment set forth in FIG. 1, because the column switches 114-1 to 114-m can be turned on at the same time by the data transfer signal DTS, all of the m columns can be selected at the same time. As a result, data can be read from or written between a channel (106-11 to 106-mn) and a memory cell of a corresponding column in response to a channel select signal (CHS1 to CHSn).
Alternatively, the same data can be supplied to a channel (106-11 to 106-mn) and a memory cell of a corresponding column at the same time in a write operation. This write operation can write data to memory cells within m columns in the memory cell array 102 and m columns in the register array 104, at the same time. Such a write operation can result in high speed resetting of data in the case of a virtual channel memory that is used to process image data.
Various operation modes for a VCSDRAM according to particular embodiments will now be described. A VCSDRAM according to one embodiment can include at least a first, second, third and fourth operation mode. In a first operation mode, the same data, for example a "0" or a "1" can be written into a row of memory cells. In a second operation mode, the same data can be written into a row of channels. In a third operation mode, the same data can be written into a row of memory cells and a row of channels at the same time. In fourth operation mode, data can be transferred between a row of memory cells and a row of channels.
For the particular embodiment of FIG. 1, prior to the described operation modes, the data transfer bus line pairs 108-1T/108-1N to 108-mT/108-mN can be precharged to an arbitrary voltage other than the GND voltage.
In the first operation mode, a row address can be applied to the VCSDRAM by a central processing unit (CPU) or the like, and a row can be selected within memory cell array 102. The data transfer signal DTS can be activated and a data write signal DS1 can also be activated (driven high, in FIG. 1). One data bus transfer line 108-1T to 108-mT from each data bus transfer line pair will be driven to a lower potential than the other data bus transfer line 108-1N to 108-mN of its corresponding data bus transfer line pair.
Because the column switches (114-1 to 114-m) are activated, one digit line 112-1T to 112-mT from each digit line pair will be driven to a lower potential than the other digit line 112-1N to 112-mN of its corresponding digit line pair.
Sense amplifiers 116-1 to 116-m can be activated, and the same data (for example, a logic "1" established by the activation of the data write signal DS1) can be written to memory cells of the same row within the memory cell array 102. It is understood that in the particular arrangement of FIG. 1, when the data write signal DS2 is activated (driven high, in FIG. 1), a different logic value (for example a logic "0") can be written to memory cells of the same row within the memory cell array 102. In this way, a row of m data having logic values of "0" or "1" can be written into memory cells at the same time.
In the second operation mode, one of the channel select signals (CHS1 to CHSm) is activated by a CPU or the like, instead of the data transfer signal DTS, as is the case in the first operation mode. A row of channels selected by the activated channel select signal can be reset to a logic "0" or "1" value, according to whether the DS1 or DS2 signal is activated. This can enable a row of channels to be "reset" to a particular logic value at a high speed.
In the third operation mode, a row of memory cells can be selected in the same general fashion as the first operation mode. In addition, one of the channel select signals (CHS1 to CHSm) can be activated. The operation can continue in the same fashion as the first operation mode. As a result, data values of logic "0" or "1" can be written into a row of memory cells within the memory cell array 102 and a row of channels within the register 104 at the same time.
In the fourth operation mode, a row address can be applied and a row can be selected within memory cell array 102. In addition, the data transfer signal DTS can be activated and one of the channel select signals (CHS1 to CHSm) can be activated. At the same time, the data transfer signals (DS1 and DS2) can remain inactive (low in the particular arrangement of FIG. 1). In this way data values can be transferred between a row of channels in the register array 104 and a row of memory cells in the memory cell array 102.
In a conventional approach employing memory cells and a cache memory, when the same data values (such as logic "0" and logic "1") are to be written into a row of the cache and a row memory cells, an initial write operation to the cache is performed to "reset" a cache row to the desired same data values. A subsequent write (or "restore") operation is then performed to write the same data values to a row of memory cells. In contrast, according to one embodiment of the present invention, the same data values can be written into a row of memory cells and a row of channels by only one write (restore) operation. Consequently, when a virtual channel memory according to such an embodiment is used for image processing, the reset process can be executed at a faster speed.
FIG. 2 is a block diagram of a VCSDRAM according to a second embodiment. The second embodiment can include many of the same general constituents as the first embodiment 100. To that extent, like items will be referred to with the same reference character, but with the first digit being a "2" instead of a "1." The second embodiment 200 can differ from the first embodiment 100 in that it can include a data transfer section 222 instead of a write data generating section.
The data transfer section 222 is shown to include n-channel transistors 224-11/224-12 to 224-m1/224-m2. The n-channel transistors 224-11/224-12 to 224-m1/224-m2 connect data transfer bus lines 208-1T/208-1N to 208-mT/208-mN to an external data bus 226-1/226-2. In the particular arrangement of FIG. 2, n-channel transistors 224-11/224-12 to 224m1/224-m2 are connected by their drains to data transfer bus lines 208-1T/208-1N to 208mT/208-mN, respectively. The sources of n-channel transistors 224-11 to 224-m1 are connected to external data bus line 226-1and the sources of n-channel transistors 224-12 to 224-m2 are connected to external data bus line 226-2. External bus lines 226-1/226-2 may carry signals DBT/DBN. respectively. The gates of the n-channel transistors 224-11/224-12 to 224-m1/224-m2 are connected to a data write signal DS3.
In the particular second embodiment of FIG. 2, data can be transferred between the external data bus 226-1/226-2 and various portions of the virtual channel memory (e.g., memory cells and/or registers) in the same general fashion as the first embodiment 100.
FIG. 3 is a schematic diagram of a write data producing section that may be used in the VCSDRAM of the first embodiment 100. The write data producing section of FIG. 3 is designated by the general reference character 300 and is shown to include p-channel transistors 320-11/320-12 to 320-m1/320-m2. One way in which the write data producing section 300 differs from that illustrated in FIG. 1 is that the n-channel transistors of FIG. 1 have been replaced by p-channel transistors. In addition, the sources of the p-channel transistors (320-11/320-12 to 320-m1/320-m2) are coupled to a high power supply line VCC.
In the arrangement of FIG. 3, one data transfer line of each data transfer line pair 308-1T/308-1N to 308-mT to 308-mN is driven to a logic high level to establish the logic "0" or "1" data values. Such data values can be established by the data write signals DS1 and DS2.
FIG. 4 is a schematic diagram of a data transfer section 400 that may used in the VCSDRAM of the second embodiment 200. The data transfer section 400 of FIG. 4 is designated by the general reference character 400 and is shown to include p-channel transistors 424-11/424-12 to 424-m1/424-m2. FIG. 4 also shows external bus lines 426-1and 426-2 and data transfer line pairs 408-1T/408-1N to 408-mT/408-mN. External bus lines 426-1/426-2 may carry signals DBT/DBN respectively. One way in which the write data producing section 400 differs from that of FIG. 2 is that the n-channel transistors of FIG. 2 have been replaced by p-channel transistors.
As described above, according to the present invention, a data value of logic "0" or "1" can be set in a channel register and a memory cell at the same time. This can allow for data transfers at high speeds.
It is understood that while the various particular embodiments set forth herein have been described in detail, the present invention could be subject to various changes, substitutions, and alterations without departing from the spirit and scope of the invention. Accordingly, the present invention is intended to be limited only as defined by the appended claims. | According to one embodiment, a semiconductor memory device can include a synchronous dynamic random access memory array and a register array formed from static random access memory cells. The memory device can be used in image processing, and reduce the time for data reads and writes during image reset operations. One embodiment (100) can include a memory cell array (102) having a number of memory cells arranged in rows and columns, and a register array (104) that includes a number of channel registers (106-11 to 106-mn) arranged rows and columns that correspond to at least a portion of the memory cell array rows and columns. The memory cells of a first column and the registers of a corresponding column are connected to one another by data transfer buses (108-1T/108-1N to 108-mT/108-mN). Data values can be written to memory cells and corresponding channel registers (106-11 to 106-mn) at the same time. Alternatively, data can be transferred between memory cells and corresponding channel registers (106-11 to 106-mn). | 6 |
BACKGROUND OF THE INVENTION
This invention relates to computer-aided design systems, and in particular to a system and method for providing enhanced image color processing in such a two-dimensional design system.
In a computer-aided design system, high resolution graphic capabilities provide the ability to enter images with a digital camera or allow the designer to create images using "paintbox" programs. When the image on the graphic CRT is completed, an output camera or printer may produce a hard-copy of the image. Because of the manner in which the components of a computer-aided design system interprets color, errors are introduced that cause the hard-copy image to appear differently from the image as it appears in the real world or as displayed on the graphic CRT.
SUMMARY OF THE INVENTION
The present invention is directed to providing a system and method for correcting the colors in an image in a computer-aided design system such that the image produced from the output of the system will have the desired appearance. The present invention provides the user of a computer-aided design system with tools and techniques for replacing the colors of an image with proper colors before the image is reproduced on an output device so that the color-distorting effects caused by the output process, or other colors distorting process, may be corrected. According to one aspect of the invention, a method for correcting color errors introduced in computer-generated images includes creating a color chart having one or more colors and performing the error-inducing process on the chart such that the color chart is distorted by the process. The method further includes determining the error that has been introduced by the process in adjusting the colors and images before performing the error-inducing process on the images as a function of the determined error such that the image will have correct colors after the process is performed.
While the above aspect of the invention is capable of correcting the color of images that are considered a flat-color image made up of primary colors only, many images processed in a computer-aided design system, such as photographs and images entered into the system through video cameras and the like, are composed of a myriad of differently colored pixels having (R, G, B) values which vary continuously over a large spectrum. With such continuously-colored images, it is virtually impossible to identify all of the colors in the image and to determine the correction to the colors that will produce the desired appearance of the image at the output of the system. Therefore, according to another aspect of the invention, each pixel in a continuously-colored image to be corrected is examined and, if its color is identical with one of the original colors, for which a corrected value has been determined, the color of the pixel is changed to that of the corrected value. For image pixels whose color is not identical with an original color, an interpolation from other corrected values is made in order to construct a corrected value to be applied to the pixel.
These and other related objects, advantages, and features of this invention will become apparent upon review of the following specification in conjunction with the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an illustration of CAD hardware system useful in the present invention;
FIG. 2 is a flowchart illustrating a portion of the CAD system according to the present invention;
FIG. 3 is a flowchart illustrating the color palette editing functions of the present invention;
FIG. 4 is a flowchart illustrating the color adding function of the present invention;
FIG. 5 is a flowchart illustrating the color deleting function of the present invention;
FIG. 6 is a flowchart illustrating the color replacing function of the present invention;
FIG. 7a is a flowchart illustrating the color modification using hardware feedback functions of the present invention;
FIG. 7b is a flowchart illustrating the calculate corrected color function of the present invention;
FIG. 7c is a flowchart illustrating the double exposure function of the present invention;
FIG. 8 is a flowchart illustrating the color modification with user judgment functions of the present invention;
FIG. 9 is a flowchart illustrating the display color chart based on registered color flowchart according to the invention;
FIG. 10 is a flowchart illustrating the display color chart based on corrected color function of the present invention;
FIG. 11 is a flowchart illustrating the register corrected color function of the present invention;
FIGS. 12a and 12b are a flowchart illustrating the color correction function of the present invention;
FIG. 13 is a flowchart illustrating the defining a corrected color space function of the present invention; and
FIG. 14 is a flowchart illustrating the interpolation function of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
For the purpose of the following description, there are a few assumptions made about the nature of images that are displayed on standard graphic CRTs of CAD systems. As set forth in detail in "Fundamentals of Interactive Computer Graphics", Foley, J. D. and Van Dam, A. (pp. 611-616 Addison - Wesly 1982), the disclosure of which is hereby incorporated herein by reference, the image, which is displayed in two-dimensional space, is composed of a rectangular array of pixels, the smallest unit of the CRT; and the color of each pixel is represented by its red, green, and blue components, each of which is variable between zero and 255. Thus, the (R, G, B) value determines the color of the corresponding location currently displayed on the CRT. The (R, G, B) value for each pixel of an image may be stored in the computer's memory, and retrieved when desired. The two-dimensional image may be entered as an input to the CAD system through a video camera, scanner, or by development by the user with a standard CAD software.
(I) Description of the Hardware
The hardware requirements to support the present invention are basically those needed to support a standard two-dimensional CAD system. An illustration of such a system is given in FIG. 1. The hardware includes a graphic visual input/output device such as a CRT 10 or 10', with a standard light pen 12 or mouse 14 as a locating instrument, a keyboard 16, a central processing unit 18 that will support program control of the individual pixels displayed on the graphic CRT 10 or 10' through use of a graphics command library, and a data storage unit 20, preferably a hard disk storage unit. If the images used in the system are to be input through a video input, a video camera 22 and standard associated frame capture hardware (not shown) are also required. For input of printed images, scanner 21 is provided. Images can also be inputted with a standard two-dimensional digitizing drawing device 32. Data storage unit 20 is needed for storage of the data files supporting the two-dimensional software system, including the digital graphic images. Another consideration is the number of simultaneously displayable colors possible on the graphic CRT 10 or 10' of the computer system; a minimum of 256 simultaneously displayable colors is required. Adequate facilities can be found in the Engineering Workstations currently available from several venders such as Silicon Graphics Inc., Apple Computer Inc., and SUN Microsystems.
The present invention is preferably carried out with a Silicon Graphics Inc. IRIS workstation with a three-button mouse and a graphic CRT having a viewable resolution of 768 by 1024 pixels, a central processor having 2 megabytes of main memory and a 170 megabyte hard disk for supporting 16 million simultaneously displayable colors on the graphic CRT.
The output of the system can be directed in known manner to a video tape recorder 24, an output camera 26 capable of producing color slides or photographs of various sizes, a hard-copy printer 28, or a plotter 30.
(II) Description of the Software
In this specification, the following definitions apply to these terms:
______________________________________1) Color: Representation in (R, G, B) space where R(red), G(green) and B(blue) are scalar values in the range 0.0-255.0.2) Registered Color: Any color selected by user for correction; designated (rR, rG, rB).3) Corrected Color: The "correct" color of a registered color; designated (cR, cG, cB). Is applied to the image prior to processing the image to an output device such that the image from the output device has a desired appearance.4) Color Palette: A disk file containing a set of registered colors and their corrected colors (if any). More than one color palette may exist in the system. However, the software can use only one palette at one time.______________________________________
Referring to FIG. 2, system 15 provides the tools for a user to replace the colors of an image with proper colors before the image is developed on an output device, such as a camera 26 or a graphics printer 28, using a two-dimensional CAD system programmed in accordance with the invention. Using such programmed 2-D CAD system, the user first creates and edits (34) a color palette by adding, deleting and replacing registered colors. "Correct" colors may then be found for registered colors in a palette using color analyzing functions employing hardware feedback (36) or color displaying functions which are applied by the user to allow the user to select corrected colors (38). Finally, a color palette of registered colors and corresponding corrected colors is applied in a function for applying color correction (42) to an image created in known manners at 40. Since most CAD systems are menu driven, the following will describe how a user would execute the functions by selecting from a menu displayed on the graphic CRT of the system.
(a) Creating Color Palette
The first step is to create and edit a color palette so that the system can utilize registered colors in the palette to correct the colors of an image. Basic capability for creating and editing color palette (34) can be provided in a menu with the following choices:
______________________________________ ADD registered color(s) DELETE registered color(s) REPLACE registered color(s)______________________________________
The "ADD" function permits user to add (register) a new color to the color palette by typing the (R, G, B) or by picking a color on the screen using a locating instrument such as light pen 12 or mouse 14. This new color then becomes one of the registered colors in the palette. The "DELETE" function permits user to remove registered color(s) from the palette along with the corrected color(s) by selecting the registered color(s) to be deleted using a locating instrument. The "REPLACE" function permits user to change the (R, G, B) of an existing registered color.
FIG. 3 illustrates the main flowchart for the color palette generation and editing functions 34, and outlines a function that allows the user to select various subfunctions for performing color palette editing. Once invoked from the two-dimensional CAD system (44, 46), the user is prompted to enter the name of the color palette of interest (48) using keyboard 16. If the specified palette is not found in the storage unit 20, then a new palette is generated (50, 56). If the specified palette is found, then its registered colors and corrected colors are retrieved from the storage unit 20 and stored in a global variable and an array of colored squares, representing existing registered colors in the selected color palette, are displayed (52) in the menu area of the graphic CRT. The system then displays a menu for the user to select (54, 58) among the individual subfunctions 60-64 provided for palette editing. Each of the subfunctions 60-64 that may be invoked by a user selection performs a portion of the palette editing function. Once each of these subfunctions 60-64 finishes its task, control is returned to the palette generating and editing function indicated by the labels R1-R3. Control is then passed back to the menu selection (US) 70 so that the user may proceed to the next function. When the "exit" function 66 is selected, this function terminates and all the parameters stored in global variables are to the storage unit 20 for later retrieval 68. Control then passes back to the two-dimensional CAD system (43, 44).
FIGS. 4, 5 and 6 are flowcharts for the subfunctions for creating and editing a color palette. After the user selects the "Add color" function 60 (FIG. 4), the system receives an (R, G, B) value from user (72) by prompting the user to pick a color from the images current displayed on the graphic CRT 10 with a locating instrument or by entering the (R, G, B) value of the new color via a keyboard 16. The received color is examined (74) to see if an identical color already exists in the color palette. If so, an error message is generated (78) and this color will not be registered in the color palette. If the received color does not already exist, then the system creates a new global variable and stores (76) this (R, G, B) value which becomes one of the registered colors of the current palette. The new registered color joins other registered colors displayed on the menu area of the graphic CRT. The user can continue to add new colors to the color palette until the user indicates to the system that no additional colors are to be added (80).
FIG. 5 is a flowchart illustrating the "Delete color" function. Once this function is selected, the user is prompted to select (86) the registered color to be deleted from the color palette displayed on the menu area using a locating instrument. The system examines (88) the (x, y) coordinate obtained from the user and determines (90) if the color selected by the user is existing in the palette. If not, then an error message 94 is issued and no color is deleted. Otherwise, the selected color is deleted (92) from the current color palette and the global variable it occupied is cleared. The user can continue to delete registered colors from the color palette until the user indicates to the system that no additional colors are to be deleted (96).
FIG. 6 is a flowchart illustrating the "Replace color" function 100. In a manner similar to the "Delete color" function 62, the user is prompted to select a color and the system determines if the selected color exists for the palette (102, 104, 106, 112). Once an existing registered color is selected, the user is prompted to pick a new color on the graphic CRT using a locating instrument or to enter a new (R, G, B) value with the keyboard (108). The (R, G, B) value for this new color then replaces (110) the original one stored in the global variable. The user may repeat this function to replace additional registered colors until the user indicates to the system that no additional colors are to be replaced (114). When the "exit" function 66 is selected by the user, all the global variables associated with the registered colors are stored (68) to the storage unit 20 and the control passes to the two-dimensional CAD system 44.
(b) Finding Corrected Colors
1. Hardware Feedback
When the user is satisfied with the registered colors in the color palette, the next step is to determine the corrected color for each registered color in the palette. There are two functions that provide the user with tools for finding the corrected colors. The first function (36) provides the user with tools to send a color chart displayed in graphic CRT 10 containing the registered colors to an output device, such as camera 26, and then input the
resulting photograph of the color chart back into the system to allow the system to determine the color "error" created by the process of developing a hard-copy of the color chart by the output device. The system would then modify the (R, G, B) values of the registered colors based on the "error" to provide corresponding corrected colors which will more closely approximate the registered colors offering processing to the hard-copy. To execute the first method, the following menu is provided:
______________________________________ Display registered color chart Calculate corrected color Display corrected color chart Modify corrected color Display colors over 255______________________________________
In order to produce an image on the graphic CRT 10 of the registered colors in a palette selected by the user, the user selects the "Display registered color chart" function. The system will display all the registered colors in a color chart containing an array of colored squares, one for each registered color. The user then instructs the system to send the chart to an output device using conventional methods. The hard-copy of the image produced by the output device is then fed back to the system using an input device such as scanner 21 or the like. The user then selects the "Calculate corrected color" function to find the corrected color for each registered color. The function is accomplished by the system scanning the registered colors and determining the changes in (R, G, B) of each registered color caused by the output/input cycle. These changes then are added to the original (R, G, B) of each registered color to compensate for the "error" occurred during the output/input cycle. These new (R, G, B) values are then designated corrected colors and are stored along with their corresponding registered colors in the appropriate color palette.
The flow diagram for the function which determines corrected colors using hardware feedback (36) is illustrated in FIG. 7a. When this function is selected (124), the user is prompted to enter (126) the name of the desired color palette using keyboard 16. The system then retrieves the registered colors and corresponding corrected colors, if any, from this palette file in the storage unit 20 and stores them in a set of global variables (130). If the specified palette does not exist in the storage unit (128), this function is terminated and control passes back to the two-dimensional CAD system (44). The system displays a menu (132) for user to select (134) various subfunctions 136-144.
If the "Display registered color chart" function 136 is selected, the system displays all the registered colors of the current color palette in an array of colored squares on the graphic CRT. The user instructs the system to send this color chart to the output device to obtain a photograph or printout, and then reenters this photo, graph, or printout into the system using an input device such as scanner 21 or video camera 22 using conventional techniques. Once the previous step has been completed, the "Calculate corrected color" function (Level 1 correction) function 140 is selected. The flowchart for the Level 1 correction function is illustrated in FIG. 7b. The system will prompt the user to select an area of the color chart via an input device such as mouse 14 or light pen 10 to be corrected and obtain (250) the (X, Y) coordinates of the area selected by the user. The system then scan-converts the selected area by reading the (R, G, B) values of each pixel (252-262) of the inputted hard-copy. After reading in the new (R, G, B) values, the system calculates the "error" caused by the output/input cycle (256) and finds a corrected color (258) for each registered color.
Assuming that an existing registered color has an (R, G, B) value (rR, rG, rB), and the new (R, G, B) value after the output/input cycle is (nR, nG, nB), then the "error" is: (eR, eG, eB)=(rR-nR, rG-nG, rB-nB). Adding this "error" to the original color (rR, rG, rB), the corrected color is:
(cR, cG, cB)=(rR+eR, rG+eG, rB+eB). (1)
The corrected colors determined during this function are stored in the global variables along with their associated registered color.
Once each registered color in a palette has a corrected color, the user can apply this color palette to an image in a manner that will be set forth in detail in Section C (Correcting Image). If the image produced is still not satisfactory, then the user may fine-tune the corrected colors by selecting the "Display corrected color chart" subfunction to display all of the corrected colors in an array of squares, and the same output/input procedure as applied to the original registered colors is repeated. After the output/input cycle, the corrected color chart is again displayed on the screen and the user selects the "Modify corrected color" function (Level 2 Correction) to cause the system to determine the composite error between the modified corrected colors and the associated registered colors, in the same manner as in the "Calculate corrected color" function, by comparing the (R, G, B) values of the previous corrected colors with those just entered. In this manner, a new set of corrected colors is generated to replace the old one.
To fine-tune the corrected color, the "Display corrected color chart" function 138 and "Modify corrected color" (Level 2 correction) function 142 are selected. Functions 138 and 142 are essentially the same as the "Display registered color chart" function 136 and "Calculate corrected color" function 140 respectively except that the corrected colors previously determined by functions 136 and 140, not registered colors, are displayed and analyzed. If the new (R, G, B) value after the output/input cycle of the corrected color (cR, cG, cB) is (nR, nG, nB) and let:
D1R=cR-rR, D1G=cG-rG, D1B=cB-rB
D2R=rR-nR, D2G=rG-nG, D2B=rB-nB
then the new corrected color (ncR, ncG, ncB) is
ncR=rR+(D1 R×D1R)/(D1R-D2R);
ncG=rG+(D1G×D1G)/(D1G-D2G);
ncB=rB+(D1B×D1B)/(D1B-D2B).
While performing functions 138 and 142 to display corrected color, it is possible that one or more of the corrected colors' (R, G, B) component values will exceed 255, which is the maximum value that the graphic CRT 10' can display directly. When the "Display corrected color chart" function 138 is selected, the system will give an indication on the graphic CRT, such as "Displayed colors over 255", to apprise the user if certain displayed color values exceed the maximum. Along with providing this indication, the graphic CRT will display the excessive color values at a maximum (255) allowable intensity and will prompt the user to send this first color chart to the output device such as camera 26 as the first exposure. All colors that are below maximum intensity are displayed on the graphic CRT in their actual (R, G, B) values. After the first exposure is completed, the system prompts the user to reinsert the same film cartridge into output camera 26 for the second of a double exposure and to select the "Display colors over 255" or "Double Exposure" function 144.
The "Double Exposure" function is illustrated in FIG. 7c. This function alters the color chart display on the graphic CRT by scan-converting the color chart (264-272) and deleting all color components less than 255 from the image of the color chart by subtracting 255 from each of the "overflow" color components i.e., those that exceed 255 (268). The user is then prompted to send this modified chart to the output camera (274) for a second exposure on the same film. The "overflow" color components compound the color values on the film from the first exposure to produce the correct color.
Each time the "Display corrected color charts" and "Modify corrected color" functions 138 and 142 are selected, a new set of corrected colors is generated in the manner previously set forth to replace the previous ones. Repeated use of these two functions should achieve optimal corrected colors. While the hardware feedback function may be applied to essentially any input/output interface, it is very important that the same input/output device be used throughout the correction procedure to obtain accurate results. If the registered colors are registered from an image entered from an input camera but the photograph for the registered colors is reentered using the scanner, then there is an additional "error" between the scanner and camera, that adversely affects the accuracy of the results. When "Exit" 146 is selected by the user, all the global variables associated with the registered and corrected colors are stored to the storage unit 20 in the file for the current palette and control passes back to the two-dimensional CAD system (43, 44).
2. User Judgment
The second method (38) for finding corrected colors for registered colors provides tools to the user for creating and selecting possible corrected colors. The user, not the system, determines the desirable corrected colors. When the "Select Corrected Color" function 38 is selected, a plurality of colors having (R, G, B) values which vary slightly from a registered color are displayed as squares in a color chart and the user is prompted to send the chart to the output device. The user then selects from the hard-copy the square having the color that most closely matches the registered color displayed on the graphic CRT.
To execute the second method, the following menu is provided:
______________________________________Display color chart based on registered colorDisplay color chart based on corrected colorRegister corrected color______________________________________
When "Display color chart based on registered color" is selected, the user is prompted to specify the name of the color palette of interest, and the system displays all registered colors for the palette in an array of squares in the menu area and prompts the user to pick the registered color of interest with a locating instrument. After a registered color ("current registered color") is selected, the system then prompts user to select the range of the colors to be displayed by selecting a range number. The smaller the number entered, the smaller the difference among the colors of the displayed chart. Once a range is selected, the system then displays a new color chart on the graphic CRT which is composed of colors whose (R, G, B) components are obtained by slightly varying the current registered color. Each chart normally has 30 to 60 different colors with the original registered color displayed as a large area in the middle of the chart. The user is then prompted to send the color chart to the output device. By comparing each color on the hard-copy photograph or print with the original registered color displayed on the graphic CRT, the user judges which colored square produces the color on the photograph that most closely matches the registered color. This color will then be selected as the first corrected color candidate for the current registered color.
The "Register corrected color" function allows user to select the color square that will be designated the corrected color for the current registered color. The system will prompt the user to pick the corrected color from the color chart on the graphic CRT according to its location on the hard-copy using a locating instrument, and prompts the user to pick the corresponding registered color from the menu area. The registered color and its new corrected color are both stored as a pair.
Once an initial corrected color is selected, the user may fine-tune the corrected color by selecting "Display color chart based on corrected color" function. This function is identical to the "Display color chart based on registered color" function, except that the colors displayed in the chart are variations of the presently selected corrected color of the current registered color. By sending the displayed chart to the output device and evaluating the hard-copy, the user again selects a color that the user judges to be closest to the displayed corrected color. By initially using a larger range number and gradually decreasing the range number while repeating this function, the user can quickly find the desired corrected colors efficiently.
When the "Select Corrected Color" function is selected, steps 150 to 156 (FIG. 8) are performed in a manner that is identical to steps 124 to 130 in FIG. 7. A desired color palette will be retrieved from the disk and the parameters for the registered and corrected colors of the palette will be loaded into global variables. The menu choices for this function are displayed (158) and the user is prompted (160) to select a subfunction from the menu. There are three subfunctions 162-166 for user to select, plus an "Exit" function.
FIG. 9 illustrates the flow diagram for the "Display color chart based on registered color" function 162. When this function is selected, the user is prompted to select (172) the registered color of interest from the color palette using a locating instrument. Once a valid registered color is selected, the user is prompted to enter (174) a range number such as 1, 2 or 3 via the keyboard. The larger the number entered, the bigger the difference among the colors of the displayed chart. The system then generates (176) 30 to 60 colors to be included in a color chart by increasing and decreasing each of the (R, G, B) components of the registered color as a function of the range number selected. The generated color chart is displayed (176) on the graphic CRT with the registered color in the center. The user is then prompted to instruct the system to send the displayed chart to the output device for producing a hard-copy photograph or print.
FIG. 10 illustrates the flow diagram for the "Display color chart based on corrected color" function 164. The steps in this function are identical to those in FIG. 9, except that the chart is generated based on the corrected color of a registered color rather than the registered color. When a registered color is selected (178) and a range number is entered 180 by user, the corrected color of the selected registered color is retrieved from the global variable and new colors are generated (182). Since these colors in the chart include variations of the (R, G, B) values of the current corrected color, the user may find a better corrected color than the previous one from this chart. Once the color chart is displayed on the screen, the chart image is sent to the output device. The user then determines which color of the color chart on the photograph or print is closest to the registered color.
FIG. 11 illustrates the flow diagram of the "Register corrected color" function 166. When this function is selected, the user is prompted to select a color from the charts generated by subfunction 162 or 164 for inclusion in the list of corrected colors. With a chart displayed on the graphic CRT, the user is prompted to select a registered color from the color palette (186) using a locating instrument and to select (188) the corrected color selected by the user to correspond to the registered color. After both colors are picked by the user, the system then pairs them together and stores them in global variables. When the user selects the "Exit" subfunction, this function 38 is exited and the color data stored in the global variables are stored (170) to the storage unit for later retrieval. Control passes back to the two-dimensional CAD system (43, 44).
(c) Correcting Image
Once the user has created one or more color palettes containing corrected colors for corresponding registered colors, and with an image whose colors are to be corrected displayed on the graphic CRT 10', correction of the colors of this image (42) may proceed based upon their relationship to the registered colors in the selected color palette. The capability for correcting the image can be provided in a menu with the following choices:
______________________________________ Correct flat-colored image Correct continuously-colored image______________________________________
After the user has specified the color palette to apply to the image., this function will use the registered colors and their corrected colors in the specified color palette to adjust the (R, G, B) values for all pixels in the image based upon their relationship to the registered colors. To apply this function, the user must determine whether the image to be corrected is a flat-colored image or a continuously-colored image. A flat-colored image is an image composed of only "pure" colors with large regions of the image having only a single color rather than a mixture of similar colors. A continuously-colored image is an image composed of many colors, with many similar colors in a small region of space combined to give the appearance of a single color. Most photograph images are continuously-colored images, whereas an image created using a "paint program", which is a standard feature of many two-dimensional CAD systems, will typically be a flat-colored image.
FIGS. 12-14 illustrate the flowchart for the color correction function. Before selecting this function, the user should,
1) Display the image to be corrected on the graphic CRT; and
2) Know which color palette has the desired registered and corrected colors for correcting the displayed image.
Referring to FIG. 12, when the user selects the "color correction" function 42, the system prompts the user (198) to specify the color palette to apply and stores the color data (200) from that palette into the global variables. The system prompts the user to locate (202), using a locating instrument, the upper left corner (Xu, Yu) and the lower right corner (X1, Y1) of the area of the displayed image to which correction is to be applied. The system then prompts the user to select (204) one of the two subfunctions, "Correct flat-colored image" and "Correct continuously-colored image", to use in correcting the image. If "flat-colored image" is selected, the system scans the specified area horizontally from Yu to Y1 and modifies the colors of the image area line by line 208-218 (FIG. 12b). For each scan line from Xu to X1, and for each pixel in each line (for Xu to X1), the system stores (210) the (R, G, B) parameters into a temporary array of variables. The system compares the (R, G, B) value for each pixel in the array to the global variables containing the color data for the current registered colors and the corrected colors to find the matching registered color, and replaces (212) the color of the pixel with the corresponding corrected color. If no registered color matching the (R, G, B) value of a particular pixel is found, the (R, G, B) value of this pixel is unchanged.
If the user selects the "continuously-colored" subfunction at 204, the system will first redefine the color space (206) based on the positions of the registered and corrected colors in the regular color space. As illustrated in FIG. 13, in order to redefine the color space, the system will retrieve the values of the corrected colors and corresponding registered colors (232) and subdivide the color space into tetrahedrons (234) based on the positions of the registered colors in the color space. The data structure for each tetrahedron includes the location of its four vertices including the (R, G, B) coordinates of the registered color, and the (R, G, B) values of the associated corrected color (236). Once the new color space is established, a unique interpolation method is applied (220-230) to each pixel in the image to determine a corrected color (FIG. 12b).
For "continuously-colored" images, the system will calculate the (R, G, B) value of the corrected color to replace the original (R, G, B) value of each pixel in the image by a Color Cube Subdivision technique. This technique is an interpolation technique utilizing the color space that has been defined in step 206. The coordinates in the color space that include registered colors having corresponding corrected colors and the coordinates of the corners of the space or cube, define the vertices of tetrahedrons that subdivide the entire color space into 3-D volumes. Once the new color space is defined, it is tested for no separation or overlap of the tetrahedrons for proper size and shape in the tetrahedrons.
Once the color space has been subdivided into tetrahedrons, with each tetrahedron enclosing some volume of the color space, color coordinates within the color space that do not correspond to existing registered colors will fall within the volume defined by one of the tetrahedrons, and the corrected color assigned to such coordinates will be determined through interpolation of the corrected colors previously identified for the color points serving as the vertices of the tetrahedron. During this interpolation process, each of the tetrahedron vertices will have some influence over the corrected color value assigned to such coordinate; the closer the coordinate is to a vertex, the more the color value will be influenced by the corrected color value of the vertex.
A linear interpolation method (214) uses the distance of a coordinate in the color space from a vertex and from the plane defined by the other three vertices in the tetrahedron to determine the amount of influence of the vertex on the corrected color value assigned to the coordinate. If the coordinate is the same distance from the plane as is the current vertex, the coordinate would coincide with the current vertex, and the assigned corrected color value would be that corresponding to the vertex. Conversely, if the coordinate lies in the plane, the assigned corrected color value would not be influenced by the corrected color value of the vertex. If the coordinate lies between the vertex and the plane, the amount of influence of the vertex to the corrected color value assigned to the coordinate is proportional to the distance of the coordinate from the plane. This interpolation is performed for all four vertices in the tetrahedron, and the distance ratios are summed and adjusted so they add up to one. The final corrected color value assigned to the coordinate in the new defined color space is determined as a function of these ratios and the corrected color values assigned to the vertices of the tetrahedron.
FIG. 14 illustrates the flowchart for interpolating the corrected color. The system examines (238) each tetrahedron in the new color space to find the one containing the (R, G, B) coordinate of the image pixel to be corrected. Then the distances from this coordinate to each vertex of the tetrahedron and the distances to each plane defined by the other three vertices are calculated (240, 242). The ratio of "influence" of each vertex over the final corrected color is determined (244, 246) proportional to the distances calculated in 240 and 242. Once the ratios are determined, the corrected color value of this point is calculated (248) by multiplying the ratio of each vertex to the value of its corresponding corrected color to get its "contribution" to the (R, G, B) components, and adding the contributions from each vertex together to get the final (R, G, B) value of the corrected color for the pixel. Finally, the original color of the pixel is replaced by this corrected color in the array and the correction procedures are applied to next pixel until all the pixels in the array are corrected. The array of colors defining the displayed image is replaced with the proper corrected colors.
If the image produced by applying the current set of corrected colors obtained from the previous function is not satisfactory, then the user may fine-tune the corrected colors to obtain more satisfactory corrected colors and repeat the color correction function.
Changes and modifications in the specifically described embodiments can be carried out without departing from the principles of the invention. Although the invention has been illustrated for correcting errors introduced by producing hard-copy outputs of an image, it is to be understood as applying equally to other output techniques such as video tape or the like. The invention may be applied to any process in a CAD system that induces error in the color components of an image and is not limited to output processes. The protection afforded the invention is intended to be limited only by the scope of the appended claims, as interpreted according to the principles of patent law including the doctrine of equivalents. | A system and method for correcting errors in the colors of an image in a computer-aided design system; such errors being introduced by a process such as the production of a hard-copy of an image displayed on a graphic CRT. Tools are provided for the user to select "registered" colors and to determine, either manually or by system calculation, corrected values of such registered colors that will produce the desired image on the hard-copy. The manual selection technique provides tools for iteratively creating charts of related, but varied, color squares and sending the charts to the output device. The resulting hard-copy is compared by the user with the chart displayed on the CRT and the user's selection is processed by the system. In the other technique, the hard-copy image of such color chart is re-entered to the system through an input device and the error between the original and processed color patches is calculated and applied to determine corrected colors. Once a palette of registered and corrected colors is developed, it may be applied to correct images composed of such registered colors or to correct images composed of virtually any combination of colors. For the latter type of images, color values in the image that do not correspond to "registered" colors are corrected by creating a new 3-D color space based upon the existing registered colors and assigning a corrected value of each color as a result of the "influence" of adjacent registered colors in the created color space. | 7 |
FIELD OF THE INVENTION
[0001] The present invention relates to new and improved processes for the preparation of Indacaterol and pharmaceutically acceptable salts thereof as well as intermediates for the preparation of Indacaterol.
BACKGROUND OF THE INVENTION
[0002] The compound 5-[(R)-2-(5,6-diethyl-indan-2-ylamino)-1-hydroxyethyl]-8-hydroxy-(1H)-quinolin-2-one, which is known as Indacaterol (INN), and its corresponding salts are beta-selective adrenoceptor agonists with a potent bronchodilating activity. Indacaterol is especially useful for the treatment of asthma and chronic obstructive pulmonary disease (COPD) and is sold commercially as the maleate salt.
[0003] WO 00/75114 and WO 2004/076422 describe the preparation of Indacaterol for the first time through the process:
[0000]
[0004] The condensation between the indanolamine and the quinolone epoxide leads to the desired product but always with the presence of a significant amount of impurities, the most significant being the dimer impurity, which is the consequence of a second addition of the product initially obtained with another quinolone epoxide, as well as the formation of another isomer which is the result of the addition of the indanolamine to the secondary carbon of the epoxide.
[0005] In addition, the reaction conditions to achieve the opening of the epoxide require high energies (ex. 21 of WO 00/75114) with temperatures of 110° C. or more for several hours, which favours the appearance of impurities.
[0006] WO 2004/076422 discloses the purification of the reaction mixture by the initial formation of a salt with an acid, such as tartaric acid or benzoic acid, hydrogenation and final formation of the maleate salt. However, the yield achieved by the end of the process is only 49% overall.
[0007] It has been found that impurities of tartrate and benzoate salts can exist in the final product as a result of displacing the tartrate or benzoate with maleate without prior neutralization to Indacaterol base. In addition, WO 2004/076422 discloses that proceeding via the free base of Indacaterol is not viable due to its instability in organic solvents. WO 00/75114 does disclose a method proceeding via the Indacaterol free base, but it is not isolated in solid form.
[0008] WO 2004/076422 furthermore discloses the method for obtaining the quinolone epoxide from the corresponding α-haloacetyl compound by reduction in the presence of a chiral catalyst, such as an oxazaborolidine compound, by proceeding via the α-halohydroxy compound.
[0009] There exists, therefore, the need to develop an improved process for obtaining Indacaterol and salts thereof, which overcomes some or all of the problems associated with known methods from the state of the art. More particularly, there exists the need for a process for obtaining Indacaterol and pharmaceutically acceptable salts thereof, which results in a higher yield and/or having fewer impurities in the form of the dimer and regioisomers impurities and/or salts other than the desired pharmaceutically acceptable salt.
SUMMARY OF THE INVENTION
[0010] In one aspect of the invention, it concerns a process for preparing Indacaterol or a pharmaceutically acceptable salt thereof comprising reacting the compound of formula I with 2-amino-5,6-diethylindan of formula II, preferably in the presence of a base, to the compound of formula III and then converting the compound of formula III to Indacaterol or a pharmaceutically acceptable salt thereof:
[0000]
[0000] wherein R 1 is a protecting group, R 2 is a protecting group, which is stable under mildly alkaline conditions, and X is a halogen selected from the group consisting of chloro, bromo, and iodo.
[0011] This process avoids the formation of the dimers and regiostereoisomers associated with the processes known in the art, e.g. in WO 2004/076422, since it avoids the use of the epoxy compound used in the prior art processes. This facilitates the purification of the compound of formula III, possible subsequent intermediates in the process, as well as the final product. The process of the invention furthermore has gentler reaction conditions than the processes known in the art and results in a yield of more than 70% and in some cases more than 80%.
[0012] R 1 is a protecting group commonly known in the art for protecting phenol groups.
[0013] R 2 is a protecting group, which is stable under mildly alkaline conditions.
[0014] A further aspect of the invention concerns a process for the preparation of the compound of formula III or a salt thereof by reacting the compound of formula I with 2-amino-5,6-diethylindan of formula II to the compound of formula III. Optionally, the compound of formula III is converted to a salt thereof by addition of an acid.
[0015] In another aspect of the invention, it concerns a process for the preparation of a pharmaceutically acceptable salt of Indacaterol by obtaining Indacaterol, isolating it in solid form, and reacting it with a suitable acid, such as maleic acid.
[0016] Still another aspect of the invention concerns the compounds of formula I. Yet another aspect of the invention concerns the compounds of formula III. A further aspect of the invention concerns Indacaterol free base in solid form.
DETAILED DESCRIPTION OF THE INVENTION
Definitions
[0017] In the context of the present invention, the term “C 6-20 aryl” is intended to mean an optionally substituted fully or partially aromatic carbocyclic ring or ring system with 6 to 20 carbon atoms, such as phenyl, naphthyl, 1,2,3,4-tetrahydronaphthyl, anthracyl, phenanthracyl, pyrenyl, benzopyrenyl, fluorenyl and xanthenyl, among which phenyl is a preferred example.
[0018] In the context of the present invention, the term “C 1-6 alkyl” is intended to mean a linear or branched saturated hydrocarbon group having from one to six carbon atoms, such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, isopentyl, neopentyl and n-hexyl.
[0019] In the context of the present invention, the term “C 1-6 -alkoxy” is intended to mean C 1-6 -alkyl-oxy, such as methoxy, ethoxy, n-propoxy, iso-propoxy, n-butoxy, iso-butoxy, sec-butoxy, tert-butoxy, n-pentoxy, iso-pentoxy, neo-pentoxy and n-hexoxy.
[0020] In the context of the present invention, the term “C 2-6 alkenyl” is intended to cover linear or branched hydrocarbon groups having 2 to 6 carbon atoms and comprising one unsaturated bond. Examples of alkenyl groups are vinyl, allyl, butenyl, pentenyl and hexenyl.
[0021] In the context of the present invention, the term “C 3-6 cycloalkyl” is intended to mean a cyclic hydrocarbon group having 3 to 6 carbon atoms, such as cyclopropyl, cyclobutyl, cyclopentyl and cyclohexyl.
[0022] In the context of the present invention, the term “heteroaryl” is intended to mean a fully or partially aromatic carbocyclic ring or ring system where one or more of the carbon atoms have been replaced with heteroatoms, e.g. nitrogen (═N— or —NH—), sulphur, and/or oxygen atoms. Examples of such heteroaryl groups are oxazolyl, isoxazolyl, thiazolyl, isothiazolyl, pyrrolyl, imidazolyl, pyrazolyl, pyridinyl, pyrimidinyl, pyrazinyl, pyridazinyl, triazinyl, coumaryl, furyl, thienyl, quinolyl, benzothiazolyl, benzotriazolyl, benzodiazolyl, benzooxozolyl, phthalazinyl, phthalanyl, triazolyl, tetrazolyl, isoquinolyl, acridinyl, carbazolyl, dibenzazepinyl, indolyl, benzopyrazolyl, phenoxazonyl, phenyl pyrrolyl and N-phenyl pyrrolyl.
[0023] In the present context, the term “optionally substituted” is intended to mean that the group in question may be substituted one or several times, preferably 1-3 times, with group(s) selected from hydroxy (which when bound to an unsaturated carbon atom may be present in the tautomeric keto form), C 1-6 -alkoxy, C 2-6 -alkenyloxy, carboxy, oxo (forming a keto or aldehyde functionality), C 1-6 -alkoxycarbonyl, C 1-6 -alkylcarbonyl, formyl, aryl, aryloxycarbonyl, aryloxy, arylamino, arylcarbonyl, heteroaryl, heteroarylamino, heteroaryloxycarbonyl, heteroaryloxy, heteroarylcarbonyl, amino, mono- and di(C 1-6 -alkyl)amino, carbamoyl, mono- and di(C 1-6 -alkyl)aminocarbonyl, amino-C 1-6 -alkyl-aminocarbonyl, mono- and di(C 1-6 -alkyl)amino-C 1-6 -alkyl-aminocarbonyl, C 1-6 -alkylcarbonyl amino, cyano, guanidino, carbamido, C 1-6 -alkyl-sulphonyl-amino, aryl-sulphonyl-amino, heteroaryl-sulphonyl-amino, C 1-6 -alkanoyloxy, C 1-6 -alkyl-sulphonyl, C 1-6 -alkyl-sulphinyl, C 1-6 -alkylsulphonyloxy, nitro, C 1-6 -alkylthio and halogen.
[0024] In the present context, the term “mildly alkaline conditions” refers to conditions created when adding the compound of formula II, which is a base, to the compound of formula I, preferably in the presence of a further base, such as triethylamine, diisopropylethylamine (DIPEA), pyridine, 1,4-diazabicyclo[2.2.2]octane (DABCO), 4-dimethylaminopyridine (DMAP), sodium carbonate, potassium carbonate, sodium hydrogencarbonate, potassium hydrogencarbonate, sodium hydroxide, or potassium hydroxide.
Processes
[0025] In one aspect of the invention, it concerns a process for preparing Indacaterol or a pharmaceutically acceptable salt thereof comprising reacting the compound of formula I with 2-amino-5,6-diethylindan of formula II, preferably in the presence of a base, to the compound of formula III and then converting the compound of formula III to Indacaterol or a pharmaceutically acceptable salt thereof:
[0000]
[0000] wherein R 1 is a protecting group, R 2 is a protecting group, which is stable under mildly alkaline conditions, and X is a halogen selected from the group consisting of chloro, bromo, and iodo.
[0026] In one embodiment, the compound of formula III is converted to Indacaterol by first converting it to a compound of formula IV by first removing the protecting group R 2 by addition of an acid, preferably an aqueous acid, and finally isolating/purifying the compound (IV) as a salt by adding the acid HA:
[0000]
[0000] and then converting the compound of formula IV to Indacaterol or a pharmaceutically acceptable salt thereof. Processes for converting the compound of formula IV to Indacaterol or a pharmaceutically acceptable salt thereof are disclosed inter alia in WO 2004/076422.
[0027] In a further embodiment, the compound of formula IV is converted to Indacaterol or a pharmaceutically acceptable salt thereof by:
a) neutralizing the compound of formula IV, removing the protecting group R 1 to obtain Indacaterol free base in solution or suspension, optionally isolating Indacaterol free base in solid form, and, optionally, obtaining a pharmaceutically acceptable salt of Indacaterol by addition of a suitable acid, such as maleic acid, to the free base; b) removing the protecting group R 1 to obtain a compound of formula V:
[0000]
neutralizing the compound of formula V to obtain the free Indacaterol base in solution or suspension, optionally isolating Indacaterol free base in solid form, and, optionally, obtaining a pharmaceutically acceptable salt of Indacaterol by addition of a suitable acid, such as maleic acid, to the free base; or
c) removing the protecting group R 1 to obtain a compound of formula V, reacting the compound of formula V directly with a suitable acid, such as maleic acid, to obtain a pharmaceutically acceptable salt of Indacaterol.
The Compound of Formula III
[0031] The compound of formula III may be isolated as the free base or through the formation of an acid addition salt without removing the protecting group R 2 or used directly without isolating it in the further preparation of Indacaterol or a pharmaceutically acceptable salt thereof, such as proceeding via the compound of formula IV.
R 1 Protecting Groups
[0032] R 1 is a protecting group commonly known in the art for protecting phenol groups. The skilled person will be aware of suitable protecting groups for hydroxy groups in the 8-position of quinolone derivatives such as the compound of formula I. Such suitable protecting groups may be found in WO 00/75114 and WO 2004/076422.
[0033] More particularly, in one embodiment, R 1 is selected from the group consisting of a C 1-6 alkyl, C 6-20 aryl, C 1-6 -alkoxy, C 2-6 alkenyl, C 3-6 cycloalkyl, benzocycloalkyl, C 3-6 cycloalkyl-C 1-6 alkyl, C 6-20 aryl-C 1-6 alkyl, heteroaryl, heteroaryl-C 1-6 alkyl, halo-C 1-6 alkyl, and an optionally substituted silyl group. In another embodiment, R 1 is benzyl or t-butyldimethylsilyl. In yet another embodiment, R 1 is benzyl.
R 2 Protecting Groups
[0034] R 2 is a protecting group, which is stable under mildly alkaline conditions and which can be cleaved off selectively under conditions where R 1 is not cleaved off. A number of protecting groups fulfil these criteria, including, but not limited to, protecting groups forming an acetal together with the adjacent oxygen atom, protecting groups forming an ether together with the adjacent oxygen, protecting groups forming a silyl ether group with the adjacent oxygen, and protecting groups forming an ester together with the adjacent oxygen. Hence, in one embodiment, R 2 forms an acetal, an ether, a silyl ether, or an ester together with the adjacent oxygen. In another embodiment, R 2 forms an acetal, an ether, or a silyl ether together with the adjacent oxygen. In yet another embodiment, R 2 forms an acetal or an ether together with the adjacent oxygen. In a further embodiment, R 2 forms an acetal together with the adjacent oxygen.
[0035] Examples of suitable acetal protecting groups are 1-(n-butoxy)-ethyl acetal and tetrahydro-pyran-2-yl acetal. Thus, in one embodiment, R 2 is 1-(n-butoxy)-ethyl or tetrahydro-pyran-2-yl, such as 1-(n-butoxy)-ethyl. Examples of suitable ether protecting groups are benzyl ether, methoxymethyl (MOM) ether, methylthiomethyl (MTM) ether, and benzyloxymethyl ether. Thus, in another embodiment, R 2 is benzyl, methoxymethyl, methylthiomethyl, or benzyloxymethyl, such as benzyl. Examples of suitable silyl ether protecting groups are trimethylsilyl ether and tert-butyldimethylsilyl ether. Thus, in still another embodiment, R 2 is trimethylsilyl or tert-butyldimethylsilyl. Examples of suitable ester protecting groups are pivaloyl ester and acetate ester. Thus, in yet another embodiment, R 2 is pivaloyl or acetate.
[0036] In a further embodiment, R 2 is selected from the group consisting of 1-(n-butoxy)-ethyl, methoxymethyl, benzyl, and tetrahydro-pyran-2-yl, such as from the group consisting of 1-(n-butoxy)-ethyl, methoxymethyl, and tetrahydro-pyran-2-yl. In yet a further embodiment, R 2 is 1-(n-butoxy)-ethyl and R 1 is benzyl.
Methods for Removing the Protecting Group R 2
[0037] The protecting group R 2 may be removed from the compound of formula III by methods known in the art for the various R 2 protecting groups defined herein. In the case of R 2 forming an acetal together with the adjacent oxygen atom, R 2 may be removed by reacting with an intermediate to strong acid, preferably in the presence of water. Examples of suitable acids are hydrochloric acid, hydrobromic acid, sulfuric acid, nitric acid, phosphoric acid, camphorsulfonic acid, methanesulfonic acid, trifluoromethanesulfonic acid, and combinations thereof.
[0038] In the case of R 2 forming an ether, silyl ether, or ester together with the adjacent oxygen atom, the acids mentioned for the acetal protecting groups are also suitable for removing R 2 . Other suitable agents for removing R 2 in the case of R 2 forming an ether, silyl ether, or ester together with the adjacent oxygen atom are aqueous bases, lewis acids, hydrogen over palladium or platinum catalyst (in the case of benzyl ether), resins such as Dowex, thiols such as thiophenol, and combinations thereof.
Bases Useful in the Reaction of Compounds I and II
[0039] Any organic or inorganic base may be employed in the reaction between compounds I and II in the formation of the compound of formula III, with the exception of primary and secondary amines. Examples of useful organic bases in this reaction are triethylamine, diisopropylethylamine (DIPEA), pyridine, 1,4-diazabicyclo[2.2.2]octane (DABCO), and 4-dimethylaminopyridine (DMAP). Examples of useful inorganic bases in this reaction are sodium carbonate, potassium carbonate, sodium hydrogencarbonate, potassium hydrogencarbonate, sodium hydroxide, and potassium hydroxide. When carrying out the reaction between the compounds of formula I and II in the presence of a base, the 2-amino-5,6-diethylindan of formula II may be added to the reaction mixture in the form of an acid addition salt thereof, such as the hydrochloride salt thereof.
The Acid HA
[0040] Reacting the product obtained by removing the protecting group R 2 from the compound of formula III with the acid HA serves to purify the compound by obtaining the salt of formula IV. Examples of suitable HA acids are benzoic acid, maleic acid, fumaric acid, succinic acid, tartaric acid, hydrochloric acid, hydrobromic acid, dibenzoyl-tartaric acid, mandelic acid, and camphorsulfonic acid.
[0041] In one embodiment, the acid HA is selected from the group consisting of tartaric acid, dibenzoyl-tartaric acid, mandelic acid, succinic acid, and benzoic acid. In another embodiment, the acid HA is selected from the group consisting of tartaric acid, succinic acid, and benzoic acid.
The Halogen X
[0042] Halogens generally constitute good leaving groups in an S N 2-type reaction, such as the reaction between the compounds of formula I and II. In one embodiment, X is selected from the group consisting of chloro, bromo, and iodo. In another embodiment, X is bromo or iodo. In yet another embodiment, X is bromo.
[0043] In a further embodiment, X is bromo or chloro and the reaction between compounds I and II takes place in the presence of an iodine salt, such sodium iodide or potassium iodide, which generates the iodo group in situ.
The Starting Compound of Formula I
[0044] The compound of formula I may be obtained from the corresponding hydroxy-unprotected compound of formula VI:
[0000]
[0000] by reacting with the reagents known in the art to form the acetal, ether, silyl ether, or ester protecting groups defined herein when reacted with an alcohol. In the case of e.g. acetal protecting groups, in the case where R 2 is 1-(n-butoxy)-ethyl or tetrahydro-pyran-2-yl, the compound of formula VI may be reacted with butyl-vinyl ether or dihydro-pyran-2-yl, respectively.
[0045] The compound of formula VI may be prepared by reducing the corresponding haloacetyl compound using a chiral catalyst. Suitable chiral catalysts for this method are disclosed in WO 2004/076422 and WO 2005/123684, the contents of which are incorporated in their entirety herein.
Pharmaceutically Acceptable Salts
[0046] Pharmaceutically acceptable acid addition salts of Indacaterol are easily identified by the skilled person. A useful list of pharmaceutically acceptable acid addition salts may be found in Berge et al: “Pharmaceutical Salts”, Journal of Pharmaceutical Sciences, vol. 66, no. 1, 1 Jan. 1977, pages 1-19. A particularly interesting pharmaceutically acceptable acid addition salt is the maleate salt.
Proceeding Via Indacaterol Base
[0047] As discussed above, Indacaterol free base is known in the art to be unstable in organic solvents. Hence, preparing pharmaceutically acceptable salts of Indacaterol by proceeding via the free Indacaterol base is not considered viable on an industrial scale. It has, however, been found that by isolating the free base in solid form, pharmaceutically acceptable salts of Indacaterol may indeed be prepared on an industrial scale by proceeding via the free Indacaterol base. Furthermore, this avoids the impurities associated with the methods known in the art for converting one salt of 8-protected Indacaterol directly to a pharmaceutically acceptable salt of Indacaterol. Example 2 of WO 2004/076422 was reproduced, hydrogenating the benzoate salt of formula IV using acetic acid as the solvent, and then exchanging the anion of the salt to maleate by addition of maleic acid. The obtained solid was filtered, washed, and dried in vacuum to give the Indacaterol maleate with impurities of Indacaterol acetate as measured by NMR (Comparative example 9).
[0048] Thus, in another aspect of the invention, it concerns a process for the preparation of a pharmaceutically acceptable salt of Indacaterol by obtaining Indacaterol, isolating it in solid form, and reacting it with a suitable acid, such as maleic acid. Indacaterol free base may be obtained as disclosed herein or as known in the art.
Useful Reaction Conditions
Formation of the Compound of Formula III
[0049] The reaction may take place in a number of different organic solvents. Useful examples are acetonitrile, butanone, and dimethylformamide (DMF), in particular acetonitrile and butanone. It has been found advantageous to use small volumes of solvent in the reaction between the compounds of formula I and II. The reaction is advantageously carried out at a temperature in the range of 70 to 110° C., such as at 85° C., with a duration of between 2 and 10 hours, such as 4 to 5 hours. Furthermore, when adding the 2-amino-5,6-diethylindan of formula II as an acid addition salt thereof, a carbonate salt, such as potassium carbonate, is advantageously added to the reaction mixture.
Removing the Protecting Group R 2
[0050] When using an aqueous acid for removing the protecting group R 2 , e.g. 1-(n-butoxy)-ethyl, from the compound of formula III said acid, such as hydrochloric acid, is advantageously added in excess, such as 2 to 6 equivalents, at a temperature between room temperature and reflux until complete removal of the protecting group, e.g. 1 to 3 hours for removing the 1-(n-butoxy)-ethyl protecting group.
Formation of the Compound of Formula IV
[0051] Once the protecting group R 2 has been removed, more water may advantageously be added together with a suitable solvent, such as dichloromethane. The deprotected compound may be neutralized at a pH of 9 to 11 and the resulting phases then separated. After separation, the solvent may be changed to a solvent suitable for precipitation of the compound of formula IV. Useful solvents are ethyl acetate, isopropanol, ethanol, acetone, tetrahydrofuran, and acetonitrile, ethyl acetate, isopropanol, and ethanol currently being more preferred. After changing the solvent, the acid HA may be added to form the compound of formula IV by precipitation. Ethyl acetate is a particularly useful solvent for precipitating the benzoate, succinate, and tartrate salts. The salt of formula IV may be obtained with a yield of 65 to 80% and a purity of greater than 93%% in the case of tartrate precipitated in ethyl acetate, and a yield of 60 to 75% and a purity of greater than 99% in the case of succinate and tartrate precipitated in isopropanol or ethanol. The absence of dimer and regioisomer impurities as known in the art facilitates a more quantitative precipitation using ethyl acetate since there is no competition for the base molecules.
Formation of Indacaterol Base
[0052] The compound of formula IV may be neutralized before deprotection of R 1 . The neutralization may suitably be achieved by addition of dichloromethane, water and soda. When R 1 is removed by hydrogenation, it may suitably be achieved using an overpressure of hydrogen at ambient temperature. Furthermore, a mixture of methanol and dichloromethane as the solvent is suitably employed in the process. Upon completion of the hydrogenation, the catalyst is removed and dichloromethane is distilled off to leave methanol as the only solvent, which causes Indacaterol to precipitate upon cooling. Alternatively, the methanol/dichloromethane mixture is exchanged with isopropanol solvent, which is cooled to achieve precipitation of Indacaterol base with a purity of >99%.
[0053] Precipitated Indacaterol base is a white solid, which may be stored at ambient temperature for extended periods of time. Upon dissolution it may be used to prepare a pharmaceutically acceptable salt, such as the maleate salt. A suitable solvent for the addition of maleic acid is isopropanol. Alternatively, Indacaterol base obtained from the reaction and dissolved in a mixture of methanol and dichloromethane can be used directly, the solvent exchanged for isopropanol, and then precipitated as the maleate salt by adding maleic acid.
Intermediate Compounds
[0054] The process of the invention involves novel intermediates, which have not previously been used in the preparation of Indacaterol. Hence, a further aspect of the invention concerns the compounds of formula I. Yet another aspect of the invention concerns the compounds of formula III, or salts thereof.
[0055] A further aspect of the invention concerns Indacaterol free base in solid form. In one embodiment, said Indacaterol free base is in crystalline form. In another embodiment, said Indacaterol free base is in amorphous form.
EXAMPLES
Example 1
Protecting the α-Halohydroxy Compound of Formula VI
[0056]
[0057] A flask was charged with 5 ml of tetrahydrofuran (THF) and 5 ml of toluene. p-toluene sulfonic acid (0.15 mmol) and molecular sieves were added with stirring for 30 minutes. 6 mmol of butyl-vinylether and 3 mmol of 8-(phenylmethoxy)-5-((R)-2-bromo-1-hydroxy-ethyl)-(1H)-quinolin-2-one were added. The mixture was agitated at 20/25° C. until completion of the reaction, followed by filtration and distillation of the filtrate to remove the solvent. The product is obtained in quantitative yield as an oil consisting of 50% of each of the diastereomers.
[0058] 1 H-NMR (DMSO-d6, δ), mixture 50/50 of diastereomers: 0.61 and 0.82 (3H, t, J=7.2 Hz, CH 3 —Pr—O), 1.12 and 1.22 (3H, d, J=5.6 Hz, acetalic CH 3 ), 0.90-1.40 (4H, m, CH 2 +CH 2 ), 3.20-3.80 (4H, m, CH 2 —OAr+CH 2 —Br), 4.51 and 4.82 (1H, q, J=5.6 Hz, acetalic CH), 5.18 and 5.24 (1H, dd, J=4.0, 8.0 Hz, CH—O-acetal), 6.56 and 6.58 (1H, d, J=10.0 Hz, H4), 7.00-7.57 (7H, m), 8.17 and 8.23 (1H, d, J=10.0 Hz, H3), 10.71 (1H, s, NH)
[0059] 13 C-NMR (DMSO-d6, δ), mixture 50/50 of diastereoisomers: 13.5 and 13.7 CH 3 ), 18.5 and 18.8 (CH 2 ), 19.9 and 20.0 (acetalic CH 3 ), 30.9 and 31.4 (CH 2 ), 36.8 and 37.3 (CH 2 ), 63.7 and 64.2 (CH 2 —Br), 69.8 and 69.9 (CH 2 —OAr), 73.8 and 75.1 (CH—O), 97.5 and 100.4 (acetalic CH), 111.8 (CH), 116.9 and 117.2 (C), 121.2 and 122.4 (CH), 122.3 and 122.6 (CH), 127.7 and 127.8 (C), 127.8 and 127.9 (CH), 128.2 and 128.3 (CH), 128.8 and 129.1 (C), 129.4 and 129.6 (C), 136.1 and 136.5 (CH), 136.5 and 136.6 (C), 144.0 and 144.2 (C), 160.7 and 160.8 (C═O).
Example 2
Protecting the α-Halohydroxy Compound of Formula VI
[0060]
[0061] Pivaloyl chloride (0.72 g) was added to a stirred mixture of 8-(phenylmethoxy)-5-((R)-2-chloro-1-hydroxy-ethyl)-(1H)-quinolin-2-one (0.74 g), dichloromethane (15 ml) and 4-dimethylaminopyridine (0.89 g) at 20/25° C., and the reaction was stirred until all the starting material disappeared. Water (22 ml) was added and the phases were separated.
[0062] The organic phase was washed with 1 M HCl (22 ml) and then with water (22 ml). The solvent was removed and the residue was crystallized from acetone to obtain 0.82 g of the product.
[0063] 1 H-NMR (DMSO-d6, δ): 1.13 (9H, s, CH 3 ), 3.92 (1H, dd, J=4.0, 12.0 Hz, CH 2 —Br), 4.00 (1H, dd, J=8.4, 12.0 Hz, CH 2 —Cl), 5.28 (2H, s, Ph-CH 2 —O), 6.25 (1H, dd, J=4.0, 8.4 Hz, CH—OPiv), 6.59 (1H, d, J=10.0 Hz, H4), 7.15 (1H, d, J=8.4 Hz, H6), 7.20 (1H, d, J=8.4 Hz, H7), 7.27-7.30 (1H, m, Ph), 7.33-7.37 (2H, m, Ph), 7.54-7.56 (2H, m, Ph), 8.18 (1H, d, J=10.0 Hz, H3), 10.77 (1H, s, NH).
[0064] 13 C-NMR (DMSO-d6, δ): 26.7 (3×CH 3 ), 38.3 (C), 46.4 (CH 2 —Cl), 69.8 (CH 2 -Ph), 71.3 (CH—OPiv), 111.9 (CH), 116.8 (C), 120.5 (CH), 122.9 (CH), 126.0 (C), 127.8 (2×CH), 127.9 (CH), 128.3 (2×CH), 129.5 (C), 136.0 (C), 136.5 (CH), 144.5 (C), 160.7 (CON), 176.2 (COO).
Example 3
Preparation of the Compound of Formula IV
[0065]
[0066] A flask was charged with 2.5 ml of THF and 2.5 ml of toluene. p-toluene sulfonic acid (5 mg) and molecular sieves (0.2 g) were added with stirring for 30 minutes. 1.5 ml of butyl-vinylether and 2 g of 8-(phenylmethoxy)-5-((R)-2-bromo-1-hydroxy-ethyl)-(1H)-quinolin-2-one were added. The mixture was agitated at 20/25° C. until completion of the reaction. 0.015 ml of diisopropylethyl amine was added, the mixture was filtered, and the solvent was distilled off.
[0067] The residue was dissolved in 6 ml of dimethylformamide (DMF), 1.9 ml of diisoproypylethyl amine, 1.2 g sodium iodide, and 1.5 g of 2-amino-5,6-diethylindane were added and the mixture was heated to 100° C. After completion of the reaction the mixture was cooled to 20/25° C., 0.4 ml of concentrated hydrochloric acid and 0.4 ml of water were added, and the mixture was stirred for 30 minutes.
[0068] HPLC analysis showed the expected product with a purity of 75% and being free from the dimer and regioisomer impurities.
[0069] 20 ml of water, 20 ml of methylene chloride, and 3 ml of 6N NaOH were added with stirring. The organic phase was separated and washed with 20 ml of water. The organic phase was distilled and the solvent was changed to ethyl acetate with a final volume of 100 ml. The mixture was heated to 70° C., 0.8 g of L-tartaric acid was added, and stirring continued for 30 minutes at 70° C. The mixture was cooled slowly to 20/25° C., filtered, and washed with 8 ml of ethyl acetate to obtain 8-(phenylmethoxy)-5-[(R)-2-(5,6-diethyl-indan-2-ylamino)-1-hydroxy-ethyl]-(1H)-quinolin-2-one tartrate in 68% yield. The purity of the product was >95% by HPLC analysis.
Example 4
Preparation of the Compound of Formula IV
[0070]
[0071] A flask was charged with 19 ml of THF and 19 ml of toluene. p-toluene sulfonic acid (75 mg) and molecular sieves (1.5 g) were added and the mixture was stirred for 30 minutes. 11.2 ml of butyl-vinylether and 15 g of 8-(phenylmethoxy)-5-((R)-2-bromo-1-hydroxy-ethyl)-(1H)-quinolin-2-one were added. The mixture was agitated at 20/25° C. until completion of the reaction. 0.1 ml of diisopropylethyl amine were added, the mixture was filtered, and the solvent was distilled off.
[0072] The residue was dissolved in 40 ml of butanone, 14.5 ml of diisoproypylethyl amine, 9 g sodium iodide, and 11.3 g of 2-amino-5,6-diethylindane were added and the mixture was heated to 90-100° C. After completion of the reaction the mixture was cooled to 20/25° C., 3 ml of concentrated hydrochloric acid and 3 ml of water were added, and the mixture was stirred for 30 minutes.
[0073] HPLC analysis showed the expected product with a purity of 84% and being free from the dimer and regioisomer impurities.
[0074] 150 ml of water, 150 ml of methylene chloride, and 22.5 ml of 6N NaOH were added with stirring. The organic phase was separated and washed with 10 ml of water. The organic phase was distilled and the solvent was changed to isopropyl alcohol with a final volume of 300 ml. The mixture was heated to 70° C., 4.9 g of benzoic acid was added, and stirring continued for 30 minutes at 70° C. The mixture was cooled slowly to 20/25° C., filtered, and washed with 30 ml of isopropanol to obtain 8-(phenylmethoxy)-5-[(R)-2-(5,6-diethyl-indan-2-ylamino)-1-hydroxy-ethyl]-(1H)-quinolin-2-one benzoate in 59% yield. The purity of the product was >99% by HPLC analysis.
Example 5
Preparation of the Compound of Formula IV
[0075]
[0076] A flask was charged with 7.5 ml of THF and 7.5 ml of toluene. p-toluene sulfonic acid (30 mg) and molecular sieves (0.6 g) were added and the mixture was stirred for 30 minutes. 4.5 ml of butyl-vinylether and 6 g of 8-(phenylmethoxy)-5-((R)-2-bromo-1-hydroxy-ethyl)-(1H)-quinolin-2-one were added. The mixture was agitated at 20/25° C. until completion of the reaction. 0.040 ml of diisopropylethyl amine were added, the mixture was filtered, and the solvent was distilled off.
[0077] The residue was dissolved in 18 ml of acetonitrile (ACN), 5.8 ml of diisoproypylethyl amine, 3.6 g sodium iodide, and 4.5 g of 2-amino-5,6-diethylindane were added and the mixture was heated to 80-90° C. After completion of the reaction the mixture was cooled to 20/25° C., 1.2 ml of concentrated hydrochloric acid and 1.2 ml of water were added, and the mixture was stirred for 30 minutes. HPLC analysis showed the expected product with a purity of 89% and being free from the dimer and regioisomer impurities.
[0078] 60 ml of water, 60 ml of methylene chloride, and 9 ml of 6N NaOH were added with stirring. The organic phase was separated and washed with 60 ml of water. The organic phase was distilled and the solvent was changed to isopropyl alcohol with a final volume of 120 ml. The mixture was heated to 70° C., 1.9 g of succinic acid was added, and stirring continued for 30 minutes at 70° C. The mixture was cooled slowly to 20/25° C., filtered, and washed with 12 ml of isopropanol to obtain 8-(phenylmethoxy)-5-[(R)-2-(5,6-diethyl-indan-2-ylamino)-1-hydroxy-ethyl]-(1H)-quinolin-2-one succinate in 56% yield. The purity of the product was >99% by HPLC analysis.
Example 6
Preparation of Indacaterol Maleate
[0079]
[0080] 28 g of 8-(phenylmethoxy)-5-[(R)-2-(5,6-diethyl-indan-2-ylamino)-1-hydroxy-ethyl]-(1H)-quinolin-2-one tartrate was dissolved in a mixture of 560 ml of dichloromethane, 560 ml of water, and 30 ml of an aqueous solution of 6N sodium hydroxide under stirring. The phases were separated and the organic phase was washed with 280 ml of water.
[0081] The organic phase was distilled to a final volume of 140 ml and 420 ml of methanol and 4.2 g of Pd/C (5%-50% water) were added. The system was purged with nitrogen and subsequently with hydrogen at an overpressure of 0.3 bar and stirring until completion of the reaction.
[0082] The catalyst was filtered off and the solvent was changed to isopropanol adjusting the final volume to 950 ml. The solution was heated to 70/80° C. and a solution of 5.4 g maleic acid in 140 ml of isopropanol was added, maintaining the temperature between 70 and 80° C. The mixture was stirred at 70/80° C. for 30 minutes and then slowly cooled to 20/25° C. The resulting suspension was filtered, the solid residue was washed with 90 ml of isopropanol and dried to obtain 18 g of Indacaterol maleate (Yield: 79%). The product showed 99.6% purity by HPLC analysis.
Example 7
Isolation of Indacaterol Free Base in Solid Form
[0083]
[0084] 1 g of 8-(phenylmethoxy)-5-[(R)-2-(5,6-diethyl-indan-2-ylamino)-1-hydroxy-ethyl]-(1H)-quinolin-2-one tartrate was dissolved in a mixture of 20 ml of dichloromethane, 20 ml of water, and 1 ml of an aqueous solution of 6N sodium hydroxide under stirring. The phases were separated and the organic phase was washed with 10 ml of water.
[0085] The organic phase was distilled to a final volume of 5 ml and 15 ml of methanol and 0.15 g of Pd/C (5%-50% water) were added. The system was purged with nitrogen and subsequently with hydrogen at an overpressure of 0.3 bar and stirring until completion of the reaction.
[0086] The catalyst was filtered off and the solvent was changed to isopropanol adjusting the final volume to 8 ml. The resulting suspension was cooled to 0-5° C., filtered and the solid residue was washed with isopropanol and dried to obtain 0.47 g of Indacaterol free base (77%) showing 99.6% purity by HPLC analysis.
[0087] A sample of Indacaterol free base stored at 20-25° C. was analysed one month later without showing any loss of purity.
Example 8
Obtaining the Maleate Salt from Indacaterol Free Base
[0088]
[0089] 0.47 g of solid Indacaterol were suspended in 20 ml of isopropanol, heated to 70/80° C., and a solution of 0.15 g of maleic acid in 5 ml of isopropanol were added, maintaining the temperature between 70 and 80° C. The mixture was cooled to 0/5° C. and filtration of the resulting solid afforded 0.52 g of Indacaterol maleate with a purity of 99.7%.
Comparative Example 9
Direct Conversion to Indacaterol Maleate
[0090] 8-(phenylmethoxy)-5-[(R)-2-(5,6-diethyl-indan-2-ylamino)-1-hydroxy-ethyl]-(1H)-quinolin-2-one benzoate (4 g) was dissolved in acetic acid (40 ml). Pd/C (5%, 50% wet, 0.6 g) was added and the product was hydrogenated under a hydrogen atmosphere. When the reaction was complete the catalyst was filtered off and the filtrate was vacuum distilled until a volume of 8 ml was reached.
[0091] Ethanol (40 ml) was added and the mixture was heated to 50° C. A solution of 1.2 g of maleic acid in 2.4 ml of ethanol was added and the mixture was seeded with indacaterol maleate and then slowly cooled to 0/5° C. The solid was filtered and washed with 5 ml of ethanol and 3 ml of isopropanol to obtain 6.0 g of indacaterol maleate.
[0092] 1H-NMR analysis of the solid showed the presence of acetic acid in 2-4% by integration of the peak at δ 1.88 (400 MHz, DMSO-d6) corresponding to acetic acid. | The invention relates to new and improved processes for the preparation of Indacaterol and pharmaceutically acceptable salts thereof as well as intermediates for the preparation of Indacaterol. The new process avoids the use of the epoxide compound known in the art and the impurities associated therewith and results in a higher yield. | 2 |
BACKGROUND OF THE INVENTION
The present invention relates to a door frame made of wood, and, more particularly, to an improved door frame structure of connecting rails and stiles that is rigid and yet easy to manufacture.
Conventionally, a wooden door frame is formed by driving metal nails to connection portions of each rail and stile. Accordingly, there are drawbacks in that the disassembly of the manufactured door frame is almost impossible, and that the replacement and repair of damaged parts are also difficult. Further, nailing weak wooden material with metal nails causes cracks in the wooden material. Therefore, conventional connection between the members results in a warp and wind of the door frame after use over a long period of time.
SUMMARY OF THE INVENTION
To solve the above problem, it is an object of the present invention to provide a door frame in which assembly between rails and stiles can be performed and that tight mating between each of the members can be maintained.
Another object of the invention is to provide a door frame which has advantages, such as reduction in noise and protection against wind, by installing highly elastic artificial plastic wood at certain positions of the stiles facing the opening and closing portions of the door.
To accomplish the above objects, there is provided a door frame comprising:
a pair of rails including first connecting ends in which at least one first hollow or more is formed; a pair of stiles including second connecting ends associated at a right angle to the first connecting ends of the rails and composed of hole(s) to be aligned with the first hollow(s); and connecting means, inserted into each of the aligned hollow(s) and hole(s), for tightly connecting the ends of the pairs of rails and stiles together into the assembled door frame.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a door frame in accordance with the present invention;
FIG. 2 is an enlarged perspective view of a part A in FIG. 1;
FIG. 3 is a longitudinal sectional view taken along line I--I of FIG. 2;
FIG. 4 is a perspective view of an anchor bolt set applied to a door frame in accordance with the present invention; and
FIG. 5 is an enlarged cross-sectional view taken along line II--II of FIG. 1.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
A preferred embodiment of the present invention will be described below in more detail with reference to the accompanying drawings.
FIG. 1 is a perspective view of a door frame in accordance with the present invention. The door frame of the invention comprises a pair of rails 10a and 10b, and a pair of stiles 11a and 11b. At sides of the first rail 10a and first and second stiles 11a and 11b, ornamental frames 13a, 15a and 15b are installed for a visually beautiful effect, respectively. The ornamental frames 13a, 15a and 15b are preferably made of a resin, an artificial plastic substance which allows improved shape variation and shock absorption. Since the structure of the rails 10a and 10b and the stiles 11a and 11b are the same, only one example of each of the two pairs will be described below. Mating ends 12a such as a male mating end having the prominence () shape are installed at both sides of the first rail 10a. Corresponding mating ends 14a, such as a female mating end having a depression () shape corresponding to the prominence shape of the combining ends 12a of the first rail 10a are installed at both sides of the first stile 11a. Each of mating ends 12a and 14a of the first rail 10a and first stile 11a is joined to each other and then is fixed with a pair of anchor bolt sets 20 as a connecting means, thereby producing a door frame of rectangular shape. The size of the door frame can be varied by varying the length of the rail 10a and stile 11a.
FIG. 2 is an enlarged perspective view of part A in FIG. 1, which shows that each of mating ends 12a and 14a of the first rail 10a and first stile 11a is closely tightened with a pair of anchor bolt sets 20. The anchor bolt sets 20 include a nut 22 having a hexagonal hole, the structural details of which are described in FIG. 4.
FIG. 3 is a longitudinal sectional view taken along line I--I of FIG. 2. At each of mating ends 12a and 14a of the first rail 10a and first stile 11a, hollows 16a and holes 17a are formed to be aligned with each other, respectively. The anchor bolt sets 20 are inserted and fixed into each of the aligned hollows 16a and holes 17a, thereby strongly tightening each of the combining ends of the first rail 10a and first stile 11a without any gaps occurring. The anchor bolt sets 20 include a nut 22 having a groove 25 into which a wrench can be inserted, a body 21 provided with a conically-shaped head 24, and a fixing tube 27 having several wings 23 which surround the conically-shaped head 24 and are connected to the body 21 with threads. Rotation of the body 21, based on rotation of the nut 22, makes the fixing tube 27 move into the conical shaped head 24 of the body 21. The moment the several wings 23 on the fixing tube 27 come into contact with the conically-shaped head 24, the several wings 23 are expanded radially outward by the pressure of the conically-shaped head 24, so as to be strongly fixed in the inner wall of the hole 17a. Then, the conically-shaped head 24 of the body 21 is joined in caught fashion to the wings 23 fixed in the inner wall. This joining causes each of the mating ends 12a and 14a of the first rail 10a and first stile 11a to be closely joined without any gaps occurring. A wide gap occurring between the rails and stiles is prevented by more firmly tightening the anchor bolt set 20, and thus the door frame is preserved from deformation preserving the door frame from deformation.
The disassembly is easily executed by a reverse sequence when repair or partial replacement of the door frame is required.
FIG. 4 is a perspective view of an anchor bolt set which is applied to the door frame in accordance with the present invention. Nut 22, a hex socket head, is disposed at the upper portion of the anchor bolt set 20, and at the lower portion the conically-shaped head 24 is formed. The fixing tube 27 having several wings 23 is connected to the body 21. The several wings 23 of the fixing tube 17 during connecting are expanded radically outward due to strong pressure from the conically-shaped head 24 of the body 21 and thereby the anchor bolt set 20 obtaining tight coherence.
FIG. 5 is an enlarged cross-sectional view taken along line II--II of FIG. 1. Each of the stiles 11a and 11b longitudinally includes first and second border portions 19a and 19b which are formed to project outwardly with a stepped shape, which is made of an artificial plastic. The border portions 19a and 19b are rigidly inserted into first and second grooves 18a and 18b formed at the stiles 11a and 11b. Since the first and second border portions 19a and 19b are mainly made of a plastic such as polyurethane, having a high elasticity, this formation prevents noise during contact with a door D installed at the stiles 11a and 11b. Furthermore, this improves contact between the door D and border portions 19a and 19b which are highly elastic, thereby reducing the probability of a gap occurring and increasing the protection against wind.
As described above, the present invention, by connecting the rails and stiles with the anchor bolt sets, enables the door frame to be easily repaired and partially replaced. The present invention also provides a strong assembly without any gaps occurring between the connective portions of each of the members, as a result of high coherence of the anchor bolt sets 20, this allows the original state of the door frame to be maintained by just tightening the anchor bolt sets 20 when deformation of the door frame due to use over a long period of time happens. The invention also allows noise reduction and protection against wind by the installation of an elastic member at certain points in contact with the door. | The present invention relates to a door frame made of wood. The door frame comprises a pair of rails, a pair of stiles and connectors. At each of the connecting ends of the rails and stiles, hollows and holes are formed, into which a connector capable of disassembly is inserted and fixed, thereby joining and tightening the rails and stiles. The door frame can maintain its integrity and still provide for convenient repair and replacement of damaged portions by disassembly of the connector. | 4 |
FIELD OF THE INVENTION
The present invention relates generally to a warehouse truck attachment that facilitates the economical transport and storage of compressible items. In a typical warehouse operation, the attachment is first loaded with compressible items. Those items are then compressed to a size that will fit within the desired shipping container, such as a boxcar or truck trailer. The attachment may then expel those items into the shipping container while maintaining the items in a compressed state. The attachment features an internal moveable loading platform that allows warehouse personnel to completely load the attachment to a greater height that would normally be possible without requiring the warehouse personnel to use ladders or platforms. The attachment also features internal rotational surfaces that expel compressed items without the need for a separate expulsion unit.
BACKGROUND OF THE INVENTION
The transportation of manufactured items, such as from manufacturer to distributor to retailer, results in a significant increase in the retail cost of such items. This is especially true for items that, due to their shape or structure, occupy a large amount of shipping container space but are of relatively light weight. Many such manufactured items contain a great amount of empty space. The conventional method of shipping such items is to simply stack them inside a standard shipping container, such as a truck trailer or boxcar, until the container is filled. Since the shipping container can typically accommodate much more weight than such items will impart when stacked in this manner, the result is a high shipping cost per unit weight for such items.
Devices that compress such items for shipping are well-known in the prior art. In particular, U.S. Pat. No. 5,340,268, issued to Alvis E. Dowty, teaches such a device that is attached to warehouse trucks. The Dowty '268 patent teaches a device with a horizontal top member that rises to allow items to be stacked within it. The top member is then lowered to compress items within the device. A ram unit is attached that forces items out of the device and into a shipping container while still in a compressed state.
Several limitations are apparent, however, in the device taught by Dowty '268. First, when a standard-size shipping container is used, the device requires that the items be stacked above the reach of shipping personnel. Items are typically placed in such devices by hand, beginning at the floor level. As the stack grows higher, it becomes more difficult for shipping personnel to load the device. In order to load the device with items such that, when compressed, the items will fill a typical shipping container, the uncompressed stack must rise well above the reach of shipping personnel on the ground. This problem is well illustrated by FIG. 4 of the Dowty '268 patent, which depicts a stack of tires in the device before compression takes place. Thus the device taught by Dowty '268 requires warehouse personnel to begin loading the device from ground level, but then finish loading from an elevated platform or other raised surface. Since loading will require shipping personnel to be near the edge of the elevated platform, and moreover will likely require them to lean over that edge to some degree, the device creates a risk that shipping personnel will fall while loading. Although safety devices to protect personnel from injury due to falling could be incorporated into an elevated platform, this would significantly increase the cost and time requirements of the loading process.
A second limitation of the device taught by Dowty '268 is its use of a ram unit for moving compressed items from the device into a shipping container. The ram unit has a vertical surface that moves from the back to the front of the device, thereby pushing out the compressed items in front of it. The requirement of an additional ram unit for expelling items makes the Dowty '268 device bulky and cumbersome. This is an especially acute problem since the device is designed to be attached to warehouse trucks. Such trucks typically must negotiate tight spaces within warehouses, moving around stacks of warehoused items, through doorways, and around walls and columns within the warehouse. The additional length of the attachment makes all such movement slower, more difficult, and more hazardous. In addition, the warehouse truck driver must be able to accurately judge the length of his vehicle in order to load and unload items. The additional length of the warehouse truck caused by the ram unit makes such judgments more difficult and more prone to error, thereby making the loading process less efficient and more hazardous.
SUMMARY OF THE INVENTION
The present invention is directed to a device that, when attached to a warehouse truck, allows for the storage and shipping of compressible items while in a compressed state. The device generally comprises an upper and lower section, the upper section having a horizontally-aligned roof, and the lower section having a horizontally-aligned floor. These upper and lower sections are connected with expansible side members such that the roof may be raised and lowered with respect to the floor. Between the roof and floor is a platform that may move up and down between the roof and floor. When the platform is lowered near the floor, items may be stacked on top of the platform. When the platform is raised, items may be stacked onto the floor under the platform. Thus the device has two separate compartments for the stacking of compressible items. Once fully loaded, the upper section can be lowered to compress the items in both compartments. In one embodiment, the platform may be allowed to float freely during the compression stage so that items both above and below it are held under the same pressure.
In a typical application, the device is first attached to the front of a warehouse truck. The truck is then driven to an area near where the desired items are stored. Those items are then loaded into the device as detailed below. The items are then compressed by forcing the upper section of the device downward. In at least one embodiment, this force may be generated by hydraulic pressure. The warehouse truck may then be driven to a shipping container, such as a truck trailer. Finally, the items may be expelled directly into the shipping container from the device while still in a compressed state. Once inside the container, the container's walls will hold the items in a compressed state until they are unloaded.
In an alternative embodiment adapted to the particular requirements related to loading items into a boxcar, the device may be moved by means other than a forklift or warehouse truck. For example, the device may be self-powered using, for example, hydraulic motors. The device may also be carried by a mobile overhead crane. Such cranes desirably employ hydraulic motors to power wheels that are steerable in any direction for ease of movement.
In contrast to the device taught by Dowty '268, the present invention allows warehouse personnel to safely load items by allowing all loading to take place at ground level. This is accomplished by loading the device in two stages. The loading process begins with the movable platform lowered to a position near the floor. Compressible items are first stacked onto the platform into an upper compartment formed between the platform and the roof. Once the items are stacked to a certain height, the roof and platform are raised so that items may be stacked onto the floor, in a lower compartment formed between the floor and the platform. Once the lower compartment is filled, the roof and platform are lowered, thereby compressing both the items between the roof and platform, and those between the platform and floor. In a preferred embodiment, the platform may float freely between the roof and floor, thereby equalizing the pressure on each of the two sections of compressed items. In this way, items may be stacked to the same height as in the device taught by Dowty '268, but warehouse personnel may safely complete the stacking process without leaving the ground.
Also in contrast to the Dowty '268 device, the present invention features powered rotational surfaces, which eliminates the need for an additional ram unit to expel compressed items. In a preferred embodiment, the powered rotational surfaces may be motor-driven belts. The rotational surfaces are located so that the loaded items are pressed against them once the unit is loaded and the items are compressed. By rotating these surfaces, the compressed items may be expelled into a shipping container while still in a compressed state. The additional bulk and length of a separate ram unit is not required, since the means for expelling compressed items is incorporated into the device internally.
OBJECTS OF THE INVENTION
An object of the invention is to provide a mechanism for storing and shipping compressible items in a compressed state.
It is a further object of the invention to allow the loading of items within the mechanism without requiring loading personnel to leave the ground.
It is a further object of the invention to expel compressed items from within the mechanism and into a storage or shipping container without requiring an external ram unit. These and other objects and advantages of the present invention will be apparent from a consideration of the detailed description of the preferred embodiments in conjunction with the drawings which are briefly described as follows:
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side elevational view, partly in cross section, of a preferred embodiment of the disclosed invention with the platform and roof in the lowered position.
FIG. 2 is a side elevational view, partly in cross section, of a preferred embodiment of the disclosed invention with the platform and roof in the raised position.
FIG. 3 is a side elevational view, partly in cross section, of a preferred embodiment of the disclosed invention with the platform partially raised and the roof in the lowered position.
FIG. 4 is a side elevational view, partly in cross section, of a preferred embodiment of the disclosed invention attached to a warehouse truck and inside a typical shipping container.
FIG. 5 is a perspective view of a preferred embodiment of the disclosed invention.
FIG. 6 is a partial elevational view, partly in section, showing omnidirectional rollers arrayed on the collapsible tubes for friction reduction.
FIG. 7A is a partial front elevation view of a collapsible tube with an anti-pinch roller.
FIG. 7B is a partial side elevation view from the inside of the present invention of a collapsible tube with an anti-pinch roller.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to FIG. 1, the general structure of a preferred embodiment of the disclosed invention may be described. Roof 12 is slidably connected to floor 10 by means of collapsible tubes 14. Each collapsible tube 14 consists of multiple pieces of hollow tubing, each of differing outer and inner diameters. For each collapsible tube 14, the piece of tubing connected to the floor 10 is the widest piece. That piece is connected to the next widest piece in such a way that the next widest piece may slide within the widest piece so that the collapsible tube 14 may contract in a telescoping fashion. This structure is repeated at each connection between pieces of the collapsible tube 14. By each piece sliding within the wider piece below it, the overall length of each collapsible tube 14 may be reduced, thereby drawing roof 12 nearer floor 10. A stop (not shown) on each piece of tubing prevents a piece from sliding completely out of the next wider piece. FIG. 1 shows each collapsible tube 14 in the fully collapsed state, such that roof 12 is in the lowered position. Collapsible tubes 14 forms the sidewalls of two compartments: an upper compartment defined by the roof 12 and the platform 18 and a lower compartment defined by the platform 18 and floor 10.
The collapsible tubes 14 may be of various shapes, such as circular or square horizontal cross sections. When items 50 (shown in outline) are compressed in the device, there is necessarily pressure of the collapsed items 50 against the sides of the collapsible tubes 14. In order to easily expel the compressed items 50, it is desirable that the friction of the collapsed items 50 against the sides of the collapsible tubes 14 be minimized. When round cross section tubes are employed, the widest telescoping piece of the tubes may be rotatably attached to the floor 10 such that the outermost telescoping piece may rotate freely, thereby allowing the collapsed items 50 to be expelled from the device with minimal friction. If tubes 14 of square cross section or of other cross sectional shapes that are not easily mounted for rotation are employed, the inner surfaces of the tubes 14 may be supplied with a plurality of casters 70 for minimizing friction as shown in FIG. 6. Omnidirectional ball type rollers of the type often employed on material handling conveyors have been found to work acceptably in the practice of the present invention.
The collapsible tubes 14 may comprise a plurality of two or more telescoping sections. As shown in FIGS. 7A and 7B the collapsible tube 14 may comprise an inner telescoping tube 81 and an outer telescoping tube 80 wherein the inner dimensions of the outer tube 80 are selected so as to slidingly receive the inner tube 81. In like manner a third, fourth, or any higher number of telescoping tubes may be arrayed to form the collapsible tube 14. At the interface where one telescoping tube slides into another, there is a possibility that items loaded into the device may be pinched when the device is compressed and the telescoping tubes slide past one another. In order to avoid this situation, each such interface in the device may be provided with anti-pinch rollers 82. The anti-pinch rollers 82 are supported on roller brackets 83 for free rotation on roller pins 84. The roller pin 84 is held in position by a "C" pin 85 or similar locking device. The roller brackets are attached to the outer telescoping tube 80 so as to support the anti-pinch roller adjacent to the interface 86 where the inner tube 81 is slidingly received in the outer tube 80. Therefore, when the device is collapsed so as to compress items placed in the device as will be described more fully hereinafter, the anti-pinch roller allows the compressed items to slide over the interface 86 without being pulled and pinched between the sliding tubes 80, 81.
Attached to the two rearmost collapsible tubes 15 is attachment point 16. In the illustrated preferred embodiment, attachment point 16 consists of a bar with a pair of hooks adapted to fit onto a standard warehouse truck 40 with its fork assembly removed. These hooks are identical to the hooks commonly used to attach the fork assembly to a warehouse truck 40. In an alternative embodiment, attachment point 16 may consist of an assembly to receive the tines of a fork assembly attached to a warehouse truck 40. Such an assembly may be mounted under floor 10. In this alternative embodiment, there would be no need to remove the fork assembly from a warehouse truck 40 before using the device.
Platform 18 is cantilevered out from one pair of the rearmost collapsible tubes 15, such that it may move vertically between floor 10 and roof 12. In the illustrated preferred embodiment, platform 18 rides along collapsible tubes 14 on casters 20. The roof 12 is connected to the platform 18 by telescoping load levelers 22. The telescoping load levelers 22, when fully extended, are shorter than the fully extended length of the collapsible tubes 14 so that when the roof 12 is lowered as shown in FIG. 1, the platform 18 is also lowered to rest on the floor 10. But when the roof 12 is raised to the fully extended position shown in FIG. 2, the telescoping load leveler 22 only extends to a lesser length than that of the collapsible tubes 14, thus lifting the platform 18 to an intermediate position between the roof 12 and the floor 10. When both the upper and lower compartments are filled with compressible items 50 (shown in outline in FIGS. 1, 2, and 3), the telescoping load levelers 22 freely retract, thereby allowing the platform 18 to float between the roof 12 and the floor 10 to achieve a balance between the compression of the items 50 in the upper compartment and the items 50 in the lower compartment.
In the illustrated preferred embodiment, conveyor belts 24 comprise the upper surface of floor 10, the lower surface of roof 12, and both the upper and lower surfaces of platform 18. Conveyor belts 24 are supported by rollers 26, spaced at regular intervals along the length of conveyor belts 24. Conveyor belts 24 are driven by drive belts 28 operatively connected to at least one of the rollers 26. Drive belts 28 are driven by one or more motors 29. In a preferred embodiment, the motors 29 may be hydraulic motors, although the invention is not so limited. Hydraulic pressure to drive the hydraulic motors may be generated by the warehouse truck 40 connected to the device at the attachment point. In one alternative embodiment, the motors 29 may be electrically powered. The motors 29 are driven at the same speed so that the belts 24 are driven at the same speed.
Various means may be employed to raise roof 12 and platform 18 with respect to floor 10. In a preferred embodiment, hydraulic pistons 31 may be employed, although the invention is not so limited. The hydraulic pistons 31 may desirably be located at the four corners of the device. This allows both for even raising of the roof 12 with respect to the floor 10, but also ensures even compression of the items 50 in the device when the pistons 31 are reversed and employed to compress the items 50 stacked in the device. Other means to raise the roof 12 and compress the items 50 stacked in the device may include electrically powered motors.
Referring to FIGS. 1-4, the operation of a preferred embodiment of the disclosed invention may now be described. Loading of the device will begin with platform 18 lowered to its lowest position, as illustrated in FIG. 1. Typically, the device will be first attached to a warehouse truck 40, after which the truck 40 will drive to a point near where the items 50 to be loaded are stored. shipping personnel will then fill the space between platform 18 and roof 12 with compressible items 50. Once this operation is complete, roof 12 is raised by hydraulic pistons 31 to its highest position above floor 10, as illustrated in FIG. 2. As described above, platform 18 is carried upward when telescoping load levelers 22 are fully extended. Shipping personnel may now load compressible items 50 into the space between platform 18 and floor assembly 10. Roof 12 is then lowered by hydraulic pistons 31, as shown in FIG. 3. The items between platform 18 and floor 10, as well as the items between roof 12 and platform 18, will be compressed as a result. During this stage, platform 18 will be allowed to float freely so that the pressure on the two groups of items will be equalized. Telescoping load levelers 22 will adjust freely to allow this movement of platform 18.
Due to the size of the loaded device, an operator of a warehouse truck might experience difficulty in seeing around the device for maneuvering the loaded device around a warehouse and for precise positioning of the device in a shipping container. For this reason, an alternative embodiment of the present invention features a video camera positioned to the front of the device and operatively connected to a video display device within the visual field of the operator so that the operator has the ability to see into blind spots not directly visible to the operator from the cab of the warehouse truck. Multiple video cameras may be desirable in some circumstances and the cameras may be provided with operator controlled directional means so that the camera may be pointed by the operator from controls located in the cab of the warehouse truck.
To unload the compressed items 50 from the device, a typical procedure would be to insert the entire device within a standard shipping container, such as a truck trailer 60, as shown in FIG. 4. The motors 29 that drive belts 24 will then be activated, so that the belts 24 begin turning. Both belt 24 on roof 12 and belt 24 on the lower side of platform 18 turn in a clockwise direction when viewed as shown in FIGS. 1-5. Belt 24 on floor 10 and belt 24 on the upper side of platform 18 turn in a counterclockwise direction. As a result, the items 50 compressed against belts 24 are expelled from the device in the direction indicated by the arrows 32. Collapsible tubes 14 turn freely, preventing the compressed items 50 from binding or sticking along the sides of the device during the expulsion process. Alternatively, collapsible tubes 14 include friction reducing means, such as ball rollers on the inner surfaces of the collapsible tubes 14. As the compressed items 50 are forced into the shipping container 60, the warehouse truck driver will back the warehouse truck 40 out from the container 60. The walls of the shipping container 60 hold the items 50 in a compressed state until they are unloaded when their shipping destination is reached.
In an alternative mode of operation, items 50 may be loaded into the device and compressed as described above. Compressed items 50 may then be left in the device for storage or for shipping. If the device itself is shipped with the compressed items 50 within it, the warehouse truck 40 simply disengages from the device once the device enters the shipping container 60 as described above. When the shipping destination is reached, a warehouse truck 40 attaches to the device and removes it with the compressed items 50 still inside. To decompress the items 50, the reverse of the procedure described above for compression of the items 50 may be employed. In this way, compressed items 50 may be easily unloaded.
In an alternative embodiment adapted to the particular requirements related to loading items into a boxcar, the device may be moved by means other than a forklift or warehouse truck. For example, the device may be self-powered using, for example, hydraulic motors. The device may also be carried by a mobile overhead crane. Such cranes desirably employ hydraulic motors to power wheels that are steerable in any direction for ease of movement.
The present invention has been described with reference to certain preferred and alternative embodiments which are intended to be exemplary only and not limiting to the full scope of the invention as set forth in the appended claims. | An apparatus and method for the transportation and storage of compressible items in a compressed state, the apparatus comprising a lower member featuring a horizontal floor; an upper member featuring a horizontal roof, the upper member being slideably connected to the lower member; a platform between the floor and roof that is slideably connected to the upper and lower member; a rotational expulsion mechanism attached to the lower member, upper member, and platform; and an attachment point, said attachment point facilitating the connection of the apparatus to a vehicle. Compressible items may be loaded onto the platform, after which the platform is raised so that compressible items may be loaded between the floor and platform. The roof may then be lowered, compressing both those items between the roof and platform and those items between the platform and floor. A rotational mechanism incorporated into the apparatus may be used to expel the compressed items into a container while maintaining them in a compressed state. | 1 |
DESCRIPTION
ORIGIN OF THE INVENTION
The invention described herein was made in the performance of work under a NASA Contract and is subject to the provisions of Section 305 of The National Aeronautics and Space Act of 1958, Public Law 85-568 (72 Stat. 435; U.S.C. 2457).
TECHNICAL FIELD
My invention relates generally to electromagnetic antennas and more specifically to flush mounted antennas for aircraft and space vehicles for such functions as communications and the like, most particularly for operation in the microwave bands.
In high performance aircraft and reentry spacecraft the problems of aerodynamic load and friction heating preclude the employment of any antenna system which wholly or partly protrudes beyond the skin surface of such high performance air/space vehicles.
The usual frequencies of operation are very high and therefore compact structures are possible, even where special radiation patterns are required. The so-called cavity-backing concept has been used in the prior art and is also used in the invention because of the opportunity for effecting radiation reenforcement due to cavity resonance.
BACKGROUND ART
In the prior art, various approaches have been taken for the implementation of flush-mounted antennas for various end uses. Some of these are adapted for flush mounting in air/space vehicles, even though deficient in certain important aspects, vis-a-vis the invention herein disclosed and described.
Cavity-backed antennas for the air/space vehicle application are particularly attractive because they readily afford flush mounting, consequently the pertinent prior art comprises cavity-backed configurations. Moreover, spiral antennas per se are known to have relatively broad beam characteristics normal to the plane of the spiral. Cavity backing of a spiral antenna is known to provide increased directional sensitivity and a favorable electrical combination otherwise, since the spiral elements are, in a sense folded, thereby permitting them to be electrically relatively long within a correspondingly small aperture.
Arrays of spiral antennas each with resonant cavity backing have been used for direction finding. Those spirals are spaced about the points of a compass and lie in vertical planes. Frequently no particular effort to compact such arrays is required, however, in U.S. Pat. No. 4,143,380 an arrangement is described in which the spirals are disposed about a cylindrical surface and share a common resonant chamber of annular cross-section within the cylindrical surface. The combination of the aforementioned Pat. No. 4,143,380 is of interest because of its teachings in respect to compaction of cavity-backed spiral antennas, but obviously it is not applicable for flush mounting, at the skin surface of an air/space vehicle.
U.S. Pat. No. 4,032,921 describes a cavity-backed spiral antenna which would readily be flush mounted, however the spiral is filamentary in nature and, even if well covered by a radome, is subject to damage from air friction heating.
A retro-directive, cavity-backed assembly of spiral radiators is shown in U.S. Pat. No. 3,508,269. Tunnel diodes are connected to provide discontinuities in the associated transmission line to cause reflection of signal energy toward the feed assembly. Etched circuit techniques are employed to produce the spiral elements from copper clad dielectric sheets. Essentially the same vulnerability to air friction heating as noted in connection with U.S. Pat. No. 4,032,921 can be attributed to this configuration.
U.S. Pat. No. 3,568,206 discloses a square filamentary sprial antenna within a square cavity. Significance is attached to a slot formed by the clearance between the cavity sidewalls and the perimeter of the spiral. Again the same vulnerability to air friction heating attaches to this device as aforementioned.
U.S. Pat. No. 4,015,264 depicts a cavity-backed spiral antenna, in which a plurality of resistively loaded monopoles are disposed within the cavity for broadbanding purposes, without overall size increase. Yet again, the filamentary spiral of this antenna would be in a plane parallel and close to the plane of the vehicle skin surface, with the result that it too would be very subject to air friction heating. Such heating produces very high localized temperatures and filamentary elements of any kind can thereby be subject to severe damage or even destruction.
The known prior art, including the teachings of the aforementioned U.S. patents do not provide truly advantageous structures for the purpose of the present invention.
DISCLOSURE OF THE INVENTION
In consideration of the state of the prior art and the limitations thereof, it may be said to have been the general object of the invention to provide an inexpensive thermal load resistant, flush mounting, cavity-backed compact antenna for air/space vehicle use. It was also desired to provide circular polarization and alternative radiation patterns as a function of excitation control. The details of such an excitation control for the purpose of radiation pattern selection will be evident as this description proceeds.
The radiating elements comprise a pair of collocated center-fed, interleaved, spiral slots in the aperture plane. The centers of the two slots are adjacent, one on either side of the center of the cavity. The slots are cut through a conductive aperture plate, the latter forming the external face of the cavity. At the center feed point of each slot, a balanced feed assembly is presented and each of these center points is fed from a split-tube coaxial balun. Both coaxial baluns extend through the cavity and through a second side thereof parallel to the aforementioned aperture plate. Beyond this second side, a comparator hybrid is instrumented in stripline medium, for example, although not necessarily in that medium. The four port comparator hybrid, a known device per se, has two output ports (sum and difference ports). Switching means are included so that the sum (Σ) or difference (Δ) port of the comparator hybrid may be selectively excited to choose a sum or difference radiation pattern. The hybrid output ports each feed one of the slot centers through the corresponding balun.
The spiralled slots cover a pattern in the aperture plate which is elliptical, the reason for this being the control of the radiation pattern.
The foregoing and other aspects of the invention will be more fully explained as this specification proceeds.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a typical antenna assembly according to the invention from the aperture surface thereof;
FIG. 1a is an expanded view of the center portion of FIG. 1;
FIG. 2 is a sectional view taken from FIG. 1 as indicated;
FIG. 3 is a partial sectional view taken orthogonally as compared to FIG. 2 showing the central area and the two split-tube baluns;
FIG. 4 is a detail in perspective showing the construction of the split-tube baluns;
FIG. 5 is a schematic block diagram showing an arrangement for electrical operation of the antenna of the invention to produce sum and difference patterns of circulary polarized radio frequency energy selectably;
FIG. 6 is an elevation plane radiation pattern for the invention operated in accordance with arrangement of FIG. 5; and
FIG. 7 in the corresponding azimuth radiation pattern for the same operation.
BEST MODE FOR CARRYING OUT THE INVENTION
Referring now to FIG. 1, a cavity backed, dual orthogonal spiral-slot antenna is depicted, having a conductive cavity enclosure 11 with a flanged aperture plate 11a. The slots are cut through the aperture plate 11a so that they communicate with the interior of the cavity. One slot comprises the pair 12 and 13, these being the halves of one slot fed at its center 12a. Similarly, the slot halves 14 and 15 comprise the other slot, fed at center point 14a. It is helpful to think of the slots as developed into a spiral pattern from a turnstile configuration in which two center-fed slots are placed orthogonally and their ends then wrapped counterclockwise (as viewed in FIG. 1) while maintaining a predetermined radial spacing. It will be realized that each portion of a given slot lies between slots of the orthogonal slot pair and it is to be noted that this orthogonality continues throughout their spiral trajectories the overall slot pattern fitting into an elliptical outline backed by an elliptical cavity.
The expanded view of the center of FIG. 1 shown in FIG. 1a shows the shape of the web of 11a at the point of feed. The coaxial balun center conductor 19 connects to this projection at the point designated 19 on FIG. 1a. The coaxial balun outer conductor is connected to the web of 11a on the other side of the slot, and accordingly the slot itself is fed from a corresponding coaxial balun .
Considering also the sectional view of FIG. 2 and also FIG. 4 at this time, one of the baluns 14a according to FIG. 4 will be seen in FIG. 2. This split-tube balun, being known per se, can be designed for the impedance conditions at the conjunction (interface) of each slot pair. In FIG. 2, balun 14a is shown passing through the cavity from the aperture plate, its center conductor 19 being connected to the metal web defining one side of the corresponding slot and the outside conductor 23 of the coaxial balun being connected to the metal web defining the other side of the same slot at the same location. The balun slot to a depth at 20 of one quarter wavelength from the slot connection splits the coaxial outer conductor into two portions 21 and 23, as illustrated in FIG. 2, avoiding interference with the connection of the center conductor 19 as it connects to the slot wall. The conductive abuttment 21a (FIG. 2) does not "short out" the coaxial balun center conductor, since the quarter-wavelength of the balun outer conductor halves gives rise to the high impedance point at 21a. The dielectric 22 in the baluns is conventional and can be selected from materials suitable at the frequency of operation.
FIG. 3 is self-explanatory and depicts the two baluns 12 and 14a as would be expected from FIG. 1. If the baluns are designed for 50 ohm characteristic impedance, the slot impedance can be approximately 120 ohms (70 ohms at the balun connection). Some design freedom obviously exists for modification of slot center-to-center radial spacing to provide a different slot impedance if desired, however the values given above are typical. The width of the slots is not critical but may conveniently be approximately equal to one half of the adjacent slot center-to-center radial spacing.
In FIG. 2, a radome 11b is shown over the aperture plate 11a, but was omitted from FIG. 1 for clarity. It will be understood that the center conductors 19 of the baluns proceed through the cavity 11c to connect to the appropriate strip conductors (branch ports) of the hybrid 30 while the outer conductors of the baluns connect to cavity wall 11c. The depth of the cavity i.e. the spacing between the aperture plate 11a and the cavity wall 11c is one quarter wavelength, that being the criterion for resonance at the center frequency of operation.
In the particular design according to the invention, the length of the spiral trace of each half of a slot pair was approximately 3.5 wavelengths, this providing relatively large bandwidth. Longer slot trajectories would afford still greater bandwidth.
In FIG. 2, a switching module 24 is shown, and it is useful to look ahead to FIG. 5 to understand the circuit connections for operation of the antenna of the invention. In FIG. 5, the stripline comparator hybrid 30 is shown with branch ports (outputs) 31 and 32 which feed the slot pair center points via the corresponding balun. Leads 16 and 17 connect to the Δ and Σ ports of hybrid 30 and each feed from a point of the relay (transfer switch) 24. The magnet coil 27 will be understood to respond to energization between terminals 28 and 29 to connect the R F terminal 26 (also visible on FIG. 1) to either 16 or 17. The unused Δ or Σ port of hybrid 30 is switched to a termination 25. The results of this switching will be seen from FIG. 6 in which excitation of the Δ hybrid terminal places a lobe peak on the zero elevation line, and excitation of the Σ hybrid port produces a difference pattern with two lobes and a null on the zero elevation line.
If the antenna were arbitrarily assumed to be mounted into the underbelly of the air/space craft, then the significance of the zero elevation line becomes a line directly downward. The azimuth pattern depicted in FIG. 7 then becomes the beam cross-section in a plane normal to the plane of the pattern of FIG. 6. The elliptical pattern 33 is that resulting from the elliptical outline of the slots in the aperture face 11a, as compared to a prior art, typical, circular, spiral radiator depicted at 34 in FIG. 7.
The mathematic relationship for the ellipiticity of the slot pattern of FIG. 1 is given as ρ (φ)=distance from center of antenna ##EQU1## where: Ao is the ellipse major axis (initially)
bo is the ellipse minor axis (initially)
α is the coefficient of spiraling (pitch)
φ is the angular distance around antenna
then ##EQU2## where θ bw =desired beamwidth.
It should be noted that the quarter wave cavity depth referred to is a near free space number whereas the quarter wave balun slot to depth 20 is somewhat shortened quarter wave due to the nature of the coaxial medium of the baluns.
The cavity backing the slot radiation structure may be filled with a low-loss dielectric material 18 if the device is to be operated at substantial power and/or high altitude. In that event, the volume of the cavity can be reduced by a factor 1/Vεr where εr is the dielectric constant of 18.
The spiral slot arrangement of FIG. 1 may be referred to as "arrayed cross-slot radiators" which will radiate circularly polarized R.F. energy in the beam patterns described.
The entire apparatus is, of course, reciprocal and accordingly, R.F. terminal 26 can provide received signals as well as accept transmitable energy.
It will be realized by those of skill in this art that stripline instrumentation of the hybrid employed can be replaced by coaxial, waveguide, or some other microwave medium. The particular instrumentation of the hybrid is not per se a part of the invention, although the hybrid is an element of the fully operative confirmation.
The foregoing and other advantages are obvious to those skilled in the art of antennas. | A flush mounting, cavity-backed, dual orthogonal slot antenna in which improved radiation pattern characteristics are obtained by making the spiral slot pattern elliptical in the aperture plane. A cavity (11) and a flanged aperture plate (11a) are shown in which one slot pair (12 and 13) is orthogonal with respect to another slot pair (14 and 15) within the aperture plate (11a). Coaxial split-tube baluns (12a and 14a) are used to drive the junctions between corresponding slot pairs. Optional cavity dielectric (18) is provided and a drive coupling arrangement includes a four port comparator hybrid (30) having ≦ and Δ ports (17 and 16) respectively, for alternate excitation to produce a single lobe or a double lobe pattern with null. Switching apparatus is provided to connect a common terminal (26) to either of the ports (17 or 16). | 7 |
BACKGROUND OF THE INVENTION
[0001] The present invention relates to an apparatus for converting images of vehicle surroundings used for, for example, a driving support system for supporting driver's visibility.
[0002] Japanese Laid-Open Patent Publication No. Hei-11-328368 discloses an apparatus for converting images of vehicle surroundings used for helping the field of vision of a driver when the driver reverses up the vehicle into a garage, brings the vehicle closer to the roadside for parking, or drives the vehicle into a crossing or a T junction where the driver's visibility is poor.
[0003] This apparatus includes an electronic camera to photograph, for example, a rear view of the vehicle, or a blind corner view (front left or right view) of the vehicle. There is an increasing need for simultaneously providing the driver with multidirectional images around the vehicle. Under the situation, the driving support system employs a plurality of cameras to pick up images around the vehicle and provide the driver with a plurality of images side by side on a display.
[0004] The arrangement and operation of an apparatus for converting images of vehicle surroundings according to a related art will be explained. The related art in the following explanation employs VGA (video graphics array) of 640×480 pixels as an image output resolution of a camera and a display resolution presented for a driver.
[0005] To absorb a difference between the image data transmission rate of a camera and the processing speed of a CPU (central processing unit), the related art arranges an input frame buffer between the camera and the CPU. The input frame buffer has two banks for each camera, and the size of each bank is selected to cover an address space of 640×680 pixels of the camera. When a frame of image data is transmitted from the camera and is completely stored in one bank of the input frame buffer, the CPU carries out an image conversion process on the bank that has stored the image data At the same time, the other bank of the input frame buffer is prepared for receiving the next frame of image data. These operations are repeated. From the bank of the input frame buffer on which the image conversion process has been conducted, the CPU reads image data according to addresses stored in a pattern memory and stores the read image data in an output memory.
[0006] When employing a plurality of cameras and displaying a plurality of images side by side on a single display, it is usual to partly thin images from the cameras and display the thinned images. If two cameras each of VGA size are employed, two systems of image data are provided from the cameras. These two systems of image data are thinned in a read process and the thinned image data is displayed on a display. To prevent images presented for the driver from flickering, the CPU usually displays a frame of image data after the image data is completely stored in the output memory.
SUMMARY OF THE INVENTION
[0007] The related art mentioned above involves a delay of one frame in the input frame buffer and another delay of one frame in the output memory when the timing of data presentation is synchronized with the timing of bank switching of the input frame buffer. Namely, the related art involves a delay of two frames in total. Suppose that an NTSC (National Television System Committee) image signaling method is employed, the delay of two frames corresponds to 66 ms (millisecond(s)). For instance, an object moving at a speed of 36 km/h, the delay of 66 ms corresponds to a 66-cm (centimeter(s)) shift from an actual position of the object. If the apparatus is used at a low speed to park the vehicle or bring the vehicle closer to the roadside, such a delay will be allowable. However, if the apparatus is used at a high speed to drive the vehicle into a crossing or T junction or to pass another vehicle, such a delay can be critical for safety. A discrepancy between an actual movement of the vehicle and a movement of an image of the vehicle on a display will cause an inconvenience for the driver. At the start of the vehicle, for example, no movement will be observed on the display although the vehicle is actually moving. At the stoppage of the vehicle, movement will be observed on the display although the vehicle is actually stopped. These discrepancies due to the operation delay of the apparatus irritate the driver and cause a serious problem for safe driving.
[0008] To solve the problem, the present invention provides an apparatus for converting images of vehicle surroundings, capable of reducing an image presentation delay on a display in a vehicle.
[0009] An aspect of the present invention provides an apparatus for converting images of vehicle surroundings that includes, at least one camera configured to start, upon receiving a synchronizing signal, photographing the surroundings of a vehicle and outputting image data representative of the photographs, an output memory configured to store image data to be displayed on a display installed in the vehicle, a pattern memory configured to store destination addresses of the output memory, and an image converter configured to generate the synchronizing signal, obtain the image data from the camera, and transfer part or the whole of the image data to the output memory according to the destination addresses stored in the pattern memory.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] FIG. 1 shows a configuration of the apparatus according to the first embodiment.
[0011] FIG. 2A is a top view showing a vehicle 11 entering a T junction where a perspective is poor and two vehicles are approaching the vehicle 11 , and FIG. 2B shows a screen of a display 5 displaying the surrounding images of the vehicle 11 provided by an apparatus for converting images of vehicle surroundings according to a first embodiment of the present invention.
[0012] FIG. 3 is a flowchart showing an operation of the apparatus for converting images of vehicle surroundings according to the first embodiment.
[0013] FIG. 4A is a schematic view showing an operation of the first embodiment and FIG. 4B is a timing chart showing the same.
[0014] FIG. 5 shows an apparatus for converting images of vehicle surroundings according to a second embodiment of the present invention.
[0015] FIG. 6 shows an example of a memory map of the pattern memory 3 .
[0016] FIG. 7 shows a flow of data in an address conversion process.
[0017] FIG. 8 is a schematic view showing an operation of the second embodiment.
[0018] FIG. 9 is a flowchart showing a main routine carried out by the apparatus of the second embodiment.
[0019] FIG. 10 is a flowchart showing a subroutine called by the main routine.
[0020] FIG. 11 shows an example of input/output timing of the apparatus for converting images of vehicle surroundings according to the present invention with image data to be presented for the driver being updated frame by frame and the address conversion process being conducted pixel by pixel.
DETAILED DESCRIPTION OF EMBODIMENTS
[0021] Various embodiments of the present invention will be described with reference to the accompanying drawings. It is to be noted that same or similar reference numerals are applied to the same or similar parts and elements throughout the drawings, and the description of the same or similar parts and elements will be omitted or simplified.
First Embodiment
[0022] FIG. 2A is a top view showing a vehicle 11 entering a T junction where a perspective is poor and two vehicles are approaching the vehicle 11 . FIG. 2B shows a screen of a display 5 displaying the surrounding images of the vehicle 11 provided by an apparatus for converting images of vehicle surroundings according to a first embodiment of the present invention. The apparatus is installed in the vehicle 11 and the images on the display 5 are presented for the driver of the vehicle 11 .
[0023] In FIG. 2A , a left camera installed at a front left position on the vehicle 11 obtains an image in a range 13 a, and a right camera installed at a front right position on the vehicle 11 obtains an image in a range 13 b. When the vehicle 11 enters the T junction, the vehicle 12 a straightly running toward the vehicle 11 from the left side is photographed by the left camera, and the vehicle 12 b straightly running toward the vehicle 11 from the right side is photographed by the right camera
[0024] In FIG. 2B , the display 5 displays blind corner views, i.e., front left and right views around the vehicle 11 . The display 5 displays the left image of the vehicle 11 picked up by the left camera in a left part 14 a of the display 5 and the right image of the vehicle 11 picked up by the right camera in a right part 14 b of the display 5 . The left part 14 a shows an image 12 a ′ of the vehicle 12 a, and the right part 14 b shows an image 12 b ′ of the vehicle 12 b. To separate the left part 14 a and right part 14 b from each other, a partition line (mask image) 15 may be set on the display 5 .
[0025] Now, an apparatus for converting images of vehicle surroundings according to the first embodiment of the present invention will be explained with reference to the drawings. According to this embodiment, an output resolution of image data picked up by each camera is VGA (640×680 pixels), and a resolution of the display 5 to present images for the driver is also VGA.
[0026] FIG. 1 shows a configuration of the apparatus according to the first embodiment In FIG. 1 , electronic cameras 1 a and 1 b for photographing the surroundings of a vehicle are installed at predetermined positions on the vehicle. The apparatus includes an image converter 2 for converting images received from the cameras, pattern memories 3 a and 3 b, an output memory 4 , and the display 5 . In FIG. 1 , numerals 10 a and 10 b are image data, 20 is a synchronizing signal, and 40 is display data presented on the display 5 for the driver.
[0027] The image converter 2 supplies the synchronizing signal 20 to the cameras 1 a and 1 b. In response to the synchronizing signal 20 , the cameras 1 a and 1 b start to transmit image data 10 a and 10 b frame by frame. An image transmission method between the cameras 1 a and 1 b and the image converter 2 is, for example, NTSC. In this case, the image converter 2 provides the synchronizing signal 20 at frame intervals, i.e., every 33 ms. The image converter 2 controls the supply of the synchronizing signal 20 , an address conversion process, and a write process. The image converter 2 has a pixel counter 24 whose capacity corresponds to the output resolution (640×680 pixels) of the cameras 1 a and 1 b. The number of the pattern memories 3 a and 3 b corresponds to the number of the cameral 1 a and 1 b, i.e., two. Each of the pattern memories 3 a and 3 b has an address space covering 640×680 pixels matching with the output resolution of each camera. The output memory 4 consists of two banks each having an address space covering 640×680 pixels matching with the resolution of the display 5 . One of the banks is used to store display data 40 to be written therein, and the other bank is used to output stored display data 40 to the display 5 .
[0028] The image converter 2 includes a controller 22 to conduct various operations, a synchronizing timer 23 to output the synchronizing signal 20 , and the pixel counter 24 . The controller 22 instructs the synchronizing timer 23 to transmit the synchronizing signal 20 to the cameras 1 a and 1 b at predetermined intervals. In response to the synchronizing signal 20 , the cameras 1 a and 1 b output data representative of photographed images. The data is transferred to the controller 22 through a bus 8 and is temporarily stored in the controller 22 . In synchronization with the synchronizing signal 20 , the controller 22 resets the pixel counter 24 to zero. The pixel counter 24 continuously increments its count at predetermined timing. The timing of the increment is set according to the timing of fetching the image data 10 a and 10 b pixel by pixel.
[0029] The controller 22 provides the pattern memories 3 a and 3 b with a count of the pixel counter 24 through the bus 8 , and the pattern memories 3 a and 3 b provide each a destination address corresponding to the count The controller 22 receives the destination addresses from the pattern memories 3 a and 3 b, and according to the received addresses, stores pixel data of the image data 10 a and 10 b in the output memory 4 . The image data 10 a from the camera 1 a is stored in the output memory 4 according to destination addresses stored in the pattern memory 3 a, and the image data 10 b from the camera 1 b is stored in the output memory 4 according to destination addresses stored in the pattern memory 3 b. These operations are conducted on each pixel data piece of the image data 10 a and 10 b. After completely storing image data for a screen of the display 5 , the output memory 4 provides the display 5 with the stored data as display data 40 , and the display 5 displays the display data 40 . As mentioned above, the output memory 4 has a bank for receiving image data and another bank for outputting display data to the display 5 . Namely, while the first bank is storing image data, the second bank provides the display 5 with display data. When the first bank completely stores a frame of image data, the first bank provides the display 5 with the stored data, and the second bank starts to receive new image data.
[0030] FIG. 3 is a flowchart showing an operation of the apparatus for converting images of vehicle surroundings according to the first embodiment. The image converter 2 transmits the synchronizing signal 20 to the cameras 1 a and 1 b at predetermined intervals. The NTSC image transmission method exemplary employed by the embodiment involves a frame period of 33 ms, and therefore, the synchronizing signal 20 serving as a trigger signal is transmitted at the intervals of 33 ms. Step S 301 starts to control the synchronizing timer 23 to provide the synchronizing signal 20 at the intervals of 33 ms.
[0031] There are two reasons to synchronize the cameras 1 a and 1 b with each other. First is to provide the driver with simultaneous information from the cameras. Second is to reduce load on the image converter 2 . Namely, in synchronization with the synchronizing signal 20 , the image converter 2 can read the pattern memories 3 a and 3 b from the start thereof when conducting an address conversion process.
[0032] When the synchronizing signal 20 is sent, step S 302 resets the pixel counter 24 to zero and starts control with the use of the pixel counter 24 . The pixel counter 24 is used to synchronize the reception timing of the image data 10 a and 10 b with the write timing to the output memory 4 . When the pixel counter 24 increments its count, the image data 10 a and 10 b are written in the output memory 4 at write addresses (destination addresses) that are stored in and read out of the pattern memories 3 a and 3 b. With the NTSC image transmission method, the image data 10 a and 10 b having the output resolution of the cameras 1 a and 1 b are transmitted within a frame transmission period of 33 ms. Namely, with the cameras 1 a and 1 b having each an output resolution of VGA (640×680 pixels), the pixel counter 24 counts up at the intervals of 107 ns.
[0033] The image data write timing mentioned above may be secured by multiplexing a timing signal over each pixel of the image data 10 a and 10 b transmitted from the cameras 1 a and 1 b and by detecting the timing signal with the image converter 2 .
[0034] In step S 303 , the image converter 2 determines whether or not the pixel counter 24 has changed its count. If the count of the pixel counter 24 has been changed, step S 304 stores a pixel of each of the image data 10 a and 10 b transmitted from the cameras 1 a and 1 b in the output memory 4 according to destination addresses stored in the pattern memories 3 a and 3 b. At timing generated by the synchronizing timer 23 , the cameras 1 a and 1 b provide the image data 10 a and 10 b pixel by pixel, which are fetched by the image converter 2 . If there is an indefinite destination address, the image converter 2 enters a sleep mode. This will be explained later in detail.
[0035] Step S 305 determines whether or not all pixels of the image data 10 a and 10 b from the cameras 1 a and 1 b have been processed. According to the first embodiment, determining whether or not all pixels of the image data 10 a and 10 b from the cameras 1 a and 1 b have been processed is conducted by determining whether or not the count of the pixel counter 24 is equal to “640×680−1.” If the count of the pixel counter 24 is below “640×680−1,” the write operation of steps S 303 to S 305 is repeated.
[0036] If the count of the pixel counter 24 is equal to “640×680−1” in step S 305 , it is determined that the image data 10 a and 10 b of one frame have completely been processed. Accordingly, the banks of the output memory 4 are switched from one to another, and image data 10 a and 10 b of the next frame are written therein. The bank of the output memory 4 into which image data has completely been written is subjected to a process of presenting the image data for the driver. The reason why the output memory 4 consists of two banks is to suppress the flickering of images to be presented for the driver.
[0037] FIG. 4A is a schematic view showing an operation of the first embodiment and FIG. 4B is a timing chart showing the same. As explained above, the cameras 1 a and 1 b provide two systems of image data 10 a and 10 b, which are transmitted pixel by pixel at predetermined intervals in synchronization with the synchronizing signal 20 , as shown in the timing chart of FIG. 4B . The image converter 2 sequentially receives the image data 10 a and 10 b at the timing mentioned above and writes the image data 10 a and 10 b into the output memory 4 at write addresses 30 a and 30 b read out of the pattern memories 3 a and 3 b, respectively. Namely, the pattern memories 3 a and 3 b store the write addresses 30 a and 30 b of the output memory 4 for the image data 10 a and 10 b, respectively, and these addresses are read out of the pattern memories 3 a and 3 b in order of output of pixels of the image data 10 a and 10 b in synchronization with the synchronizing signal 20 . Whenever the image data 10 a and 10 b are going to be output, the write addresses 30 a and 30 b are read out of the pattern memories 3 a and 3 b, and the output image data 10 a and 10 b are stored in the output memory 4 at the write addresses 30 a and 30 b. A series of these operations is the address conversion process.
[0038] When displaying a plurality of images taken by the cameras 1 a and 1 b side by side on the display 5 as shown in FIG. 2B , the images can be thinned out. Namely, it is not necessary to convert every address of the image data 10 a and 10 b. Pixels of the image data 10 a and 10 b that are not contained in the display data 40 are allocated with indefinite write addresses (represented with “xx” in FIGS. 4A and 4B ). For these thinned pixels, the image converter 2 enters a sleep mode.
[0039] The address conversion process will be explained in more detail. In FIG. 4A , pixel data ( 12 ) from the image data 10 a is stored in the output memory 4 at a write address ( 03 ), which is stored in and read out of the pattern memory 3 a At the same timing, pixel data (AB) from the image data 10 b is thinned out according to an indefinite write address (xx) of the output memory 4 stored in and read out of the pattern memory 3 b.
[0040] Pixel data ( 49 ) of the image data 10 a is thinned out according to an indefinite write address (xx) of the output memory 4 stored in and read out of the pattern memory 3 a At the same timing, pixel data ( 08 ) from the image data 10 b is written in the output memory 4 at a write address ( 04 ) that is stored in and read out of the pattern memory 3 b.
[0041] Pixel data ( 6 A) from the image data 10 a is stored in the output memory 4 at a write address ( 02 ) that is stored in and read out of the pattern memory 3 a At the same timing, pixel data ( 45 ) from the image data 10 b is thinned according to a write address (xx) of the output memory 4 stored in and read out of the pattern memory 3 b.
[0042] Pixel data ( 38 ) from the image data 10 a is thinned according to a write address (xx) of the output memory 4 stored in and read out of the pattern memory 3 a At the same timing, pixel data (SB) from the image data 10 b is stored in the output memory 4 at a write address ( 01 ) that is stored in and read out of the pattern memory 3 b.
[0043] Repeating these operations completes the transmission of a frame of the image data 10 a and 10 b. Thereafter, a next frame of image data 10 a and 10 b is transmitted.
[0044] As explained above, the apparatus according to the first embodiment employs the cameras 1 a and 1 b for photographing the surroundings of the vehicle, the image converter 2 for processing image data (image signals) 10 a and 10 b provided by the cameras 1 a and 1 b, the pattern memories 3 a and 3 b for storing write addresses, and the output memory 4 . According to the synchronizing signal 20 serving as a trigger signal provided by the image converter 2 , the cameras 1 a and 1 b provide the image converter 2 with the image data 10 a and 10 b. In response to the output of the image data 10 a and 10 b from the cameras 1 a and 1 b, the image converter 2 conducts the address conversion process to write the image data 10 a and 10 b into the output memory 4 according to the write addresses.
[0045] Thinning image data is achieved by ignoring, for example, part of the image data 10 b while writing part of the image data 10 a into the output memory 4 . This scheme can relax a concentration of operations. For example, in FIG. 4B , pixel data ( 38 ) of the image data 10 a has a destination address 30 a of (xx), and pixel data (SB) of the image data 10 b has a destination address 30 b of ( 01 ). Pixel data ( 6 A) of the image data 10 a has a destination address 30 a of ( 02 ), and pixel data ( 45 ) of the image data 10 b has a destination address 30 b of (xx). When writing part of the image data 10 a into the output memory 4 , the image data 10 b is not written into the output memory 4 . When writing part of the image data 10 b into the output memory 4 , the image data 10 a is not written into the output memory 4 . This scheme can avoid a concentration of operations.
[0046] As mentioned above, the cameras 1 a and 1 b are installed at proper positions on a vehicle and simultaneously provide image data 10 a and 10 b in response to the synchronizing signal 20 serving as a trigger. For the image data 10 a and 10 b, the address conversion process is conducted to reduce an input/output delay. Compared with the related art mentioned above, the first embodiment of the present invention may increase the size of the pattern memories 3 a and 3 b but can eliminate the input buffers of the related art and reduce an input/output delay. More precisely, the embodiment can reduce an input/output delay of two frames to one frame. Accordingly, the embodiment can provide the driver with the surrounding images of the vehicle nearly in real time to support safety driving.
[0047] Although the first embodiment employs two cameras ( 1 a, 1 b ), the present invention is applicable to a system with three or more cameras or with a single camera.
[0048] According to the first embodiment, the timing of fetching image data 10 a and 10 b from the cameras 1 a and 1 b into the image converter 2 , i.e., the timing of conducting the address conversion process is based on a signal generated by an internal or external frequency source. With this configuration, the image data 10 a and 10 b from the cameras 1 a and 1 b can be subjected to the address conversion process in real time without temporarily storing them in buffers.
[0049] The output memory 4 has two banks, and a result of the address conversion process is written in the output memory 4 bank by bank. This arrangement can suppress the flickering of the display 5 when presenting images for the driver.
[0050] The number of the pattern memories 3 a and 3 b is equal to the number of the cameras 1 a and 1 b, so that the pattern memories 3 a and 3 b are switched according to the image data 10 a and 10 b provided by the cameras 1 a and 1 b when conducting the address conversion process. If there are three or more cameras and if images of two among them are displayed side by side on the display 5 for the driver, a combination of the cameras for providing the display images is optional.
Second Embodiment
[0051] FIG. 5 shows an apparatus for converting images of vehicle surroundings according to a second embodiment of the present invention. The second embodiment assumes that the apparatus includes two cameras (i.e., an image converter 2 receives two-systems of image signals), a resolution of image data provided by each camera and a resolution of a display to display images for a driver are each VGA (640×680 pixels), and image data is updated frame by frame. Based on these assumptions, the arrangement and operation of the apparatus according to the second embodiment will be explained with reference to the drawings.
[0052] The electronic cameras 1 a and 1 b are set at predetermined positions on a vehicle, to pick up images of the surroundings of the vehicle. The apparatus includes the image converter 2 , input buffers 9 a and 9 b, a pattern memory 3 , an output memory 4 , and the display 5 to display images stored in the output memory 4 . Numerals 10 a and 10 b are image data, 20 is a synchronizing signal, and 50 is display data displayed on the display 5 for the driver.
[0053] The image converter 2 supplies the synchronizing signal 20 to the cameras 1 a and 1 b. In response to the synchronizing signal 20 , the cameras 1 a and 1 b start to transmit each a frame of image data 10 a ( 10 b ). An image transmission method between the cameras 1 a and 1 b and the image converter 2 is, for example, NTSC. In this case, the image converter 2 provides the synchronizing signal 20 at frame intervals, i.e., every 33 ms in this embodiment.
[0054] The image converter 2 controls the supply of the synchronizing signal 20 and an address conversion process. The image converter 2 has a pixel counter (not shown) whose capacity corresponds to the output resolution (640×680 pixels) of the cameras 1 a and 1 b.
[0055] The input buffers 9 a and 9 b are provided for the cameras, respectively. The size of each input buffer corresponds to the resolution of the camera and has an address space of 640×480 pixels. Each of the input buffers 9 a and 9 b may be a ring buffer to store image data in a cyclic manner. The ring buffer is a memory employing a cyclic addressing method. A data piece firstly written in a data queue in the ring buffer is read at first. Namely, the ring buffer employs a FIFO (first-in, first-out) data processing method.
[0056] A frame of image data transmitted from each of the cameras 1 a and 1 b is stored in a corresponding one of the input buffers 9 a and 9 b. Thereafter, the image converter 2 overwrites each input buffer with image data of the next frame from the start address of the input buffer. The reason why the input buffers 9 a and 9 b are each of a single bank is because the image converter 2 successively carries out an address conversion process on arrived image data, and therefore, there is no need of storing the image data for a long time, e.g., a frame period of 33 ms.
[0057] The output memory 4 consists of two banks each covering an address space of 640×480 pixels corresponding to the resolution of the display 5 . One of the banks is used to store display data to be displayed, and the other bank is used to output display data to the display 5 .
[0058] The pattern memory 3 has areas or banks whose number corresponds to the number of the cameras 1 a and 1 b, and each area or bank has an address space of 640×680 pixels corresponding to the resolution of the display 5 .
[0059] FIG. 6 shows an example of a memory map of the pattern memory 3 . In FIG. 6 , a first camera address area 41 is for the input buffer 9 a and consists of sections 401 and 402 . A second camera address area 42 is for the input buffer 9 b and consists of sections 403 and 404 . An input buffer read address area 43 consists of the sections 401 and 403 , and an output memory write address area 44 consists of the sections 402 and 404 . The section 401 is an input buffer read address section for first image data The section 402 is an output memory write address section for the first image data. The section 403 is an input buffer read address section for second image data. The section 404 is an output memory write address section for the second image data There are pointers 45 a and 45 b. For example, the two cameras 1 a and 1 b shown in FIG. 2A are employed to pick up images, which are displayed side by side on the display 5 as shown in FIG. 2B . In this case, the pattern memory 3 is divided into the address area 41 for image data 10 a from the camera 1 a and the address area 42 for image data 10 b from the camera 1 b. Image data of a pixel (pixel data) may be written into a plurality of addresses. For this, the area 43 stores, from the start thereof, read addresses of the input buffers 9 a and 9 b in order of pixel data to be input into the apparatus, and the area 44 stores write addresses of the output memory 4 in order of pixel data. In this way, an address conversion map of the pattern memory 3 covers the read addresses of the input buffers 9 a and 9 b and the write addresses of the output memory 4 . The address space of the pattern memory 3 corresponds to that of the output memory 4 . The areas 41 and 42 have the pointers 45 a and 45 b, respectively, to individually conduct an address conversion process on a plurality of image data pieces.
[0060] FIG. 7 shows a flow of data in an address conversion process. In FIG. 7 , the input buffers 9 a and 9 b, pattern memory 3 , image converter 2 , and output memory 4 are electrically connected to a bus 8 , to realize data communication among these elements. The image converter 2 (1) outputs the synchronizing signal 20 and reads an input buffer read address of pixel data on which an address conversion process is conducted from the pattern memory 3 , (2) if pixel data in the input buffers 9 a and 9 b is an object of the address conversion process, fetches the pixel data from the input buffers 9 a and 9 b, (3) reads an output memory write address from the pattern memory 3 , and (4) writes the pixel data in the output memory 4 at the output memory write address. These operations constitute the address conversion process, and the operations (1) and (2) are a read address conversion process, and the operations (3) and (4) are a write address conversion process.
[0061] FIG. 8 is a schematic view showing an operation of the second embodiment In FIG. 8 , two systems of image data are simultaneously transmitted pixel by pixel to the image converter 2 at predetermined intervals. The image converter 2 refers to the address conversion map in the pattern memory 3 , and at the timing of reception of the first pixel data, starts to sequentially write image data in the output memory 4 . Mapping a piece of pixel data to a plurality of addresses as shown in FIG. 8 takes a time. This, however, will cause no problem if the processing speed of the image converter 2 is sufficiently faster than an image data transmission rate because the input buffers 9 a and 9 b temporarily store image data frame by frame. To prevent the flickering of images, the output memory 4 consists of two banks as shown in FIG. 5 . Consequently, an input/output delay of the second embodiment is only a frame in the output memory 4 . The second embodiment is achievable without regard to the number of cameras or a display image layout of the display 5 .
[0062] As explained above, first image data and second image data corresponding to the two systems of image data 10 a and 10 b from the cameras 1 a and 1 b are transmitted pixel by pixel at predetermined intervals in synchronization with the synchronizing signal 20 . In synchronization with the sequential transmission of the first image data and second image data, the image converter 2 writes pixel data in the output memory 4 at a write address read out of the pattern memory 3 . Namely, the pattern memory 3 stores first and second write addresses of the output memory 4 for first and second pixel data to be read in this order in synchronization with the synchronizing signal 20 . Whenever the first and second pixel data are output, they are stored in the output memory 4 at the first and second write addresses read out of the pattern memory 3 .
[0063] An example of this operation will be explained with reference to FIG. 8 . Pixel data ( 12 ) from the first image data is stored in the output memory 4 at a write address ( 04 ) that is stored in and read out of the pattern memory 3 . At the same time, pixel data (AB) from the second image data is thinned according to a write address of the output memory 4 stored in and read out of the pattern memory 3 .
[0064] Pixel data ( 49 ) from the first image data is thinned according to a write address of the output memory 4 stored in and read out of the pattern memory 3 . At the same time, pixel data ( 08 ) from the second image data is stored in the output memory 4 at a write address ( 05 ) stored in and read out of the pattern memory 3 .
[0065] Pixel data ( 6 A) from the first image data is stored in the output memory 4 at write addresses ( 02 ) and ( 03 ) stored in and read out of the pattern memory 3 . At the same time, pixel data ( 45 ) from the second image data is thinned according to a write address of the output memory 4 stored in and read out of the pattern memory 3 .
[0066] Pixel data ( 38 ) from the first image data is stored in the output memory 4 at a write address ( 06 ) stored in and read out of the pattern memory 3 . At the same time, pixel data (SB) from the second image data is stored in the output memory 4 at write addresses ( 01 ), ( 07 ), and ( 08 ) stored in and read out of the pattern memory 3 . These operations are repeated until the first and second image data each of one frame are completely transmitted. Thereafter, first and second image data of the next frame are transmitted.
[0067] FIG. 9 is a flowchart showing a main routine carried out by the apparatus of the second embodiment, and FIG. 10 is a flowchart showing a subroutine called by the main routine.
[0068] The image converter 2 continuously transmits the synchronizing signal 20 at predetermined intervals to the cameras 1 a and 1 b. If the NTSC image transmission method is employed, the synchronizing signal 20 serving as a trigger signal is transmitted at the intervals of 33 ms, i.e., a frame period. At the timing of transmitting the synchronizing signal 20 , step S 601 resets the pixel counter to be explained later and address pointers N 1 and N 2 ( 45 a and 45 b of FIG. 6 ) to zero and starts control with the use of the pixel counter.
[0069] There are two reasons to synchronize the cameras 1 a and 1 b with each other. First is to provide the driver of the vehicle with simultaneous information from the cameras. Second is to reduce load on the image converter 2 . Namely, in synchronization with the synchronizing signal 20 , the image converter 2 can read the pattern memory 3 from the start thereof when conducting an address conversion process.
[0070] The pixel counter is used to synchronize the reception timing of first image data (image data 10 a from the camera 1 a of FIG. 5 ) and second image data (image data 10 b from the camera 1 b of FIG. 5 ) with the write timing of the first and second image data into the output memory 4 . At the timing when the pixel counter increments its count, pixel data is written into the output memory 4 at a write address (output memory write address) stored in the pattern memory 3 . When the NTSC image transmission method is employed, a horizontal synchronizing signal multiplexed over image data is used as a trigger to increment the pixel counter. With the NTSC image transmission method, the first and second image data having the output resolution of the cameras 1 a and 1 b are transmitted within a frame period of 33 ms. Namely, with the cameras 1 a and 1 b having each an output resolution of VGA (640×480 pixels), the pixel counter counts up at the intervals of 107 ns.
[0071] In step S 602 , the pixel converter 2 checks to see if the pixel counter has changed its count. If there is no change in the count, step S 602 is repeated.
[0072] If it is detected in step S 602 that the count of the pixel counter has changed, i.e., if pixel data has arrived, step S 603 reads, from the pattern memory 3 , a read address (input buffer read address) N 1 of the input buffer 9 a storing the first image data. Initially, N 1 =0.
[0073] Next, step S 604 calls the subroutine SUB 00 shown in FIG. 10 . Step S 701 of the subroutine SUB 00 checks to see if the input buffer read address read in step S 603 agrees with the count of the pixel counter, i.e., if the pixel data in question is an object of the address conversion process. Namely, step S 701 checks to see if the pixel data on which the address conversion process is carried out has arrived at the input buffer 9 a.
[0074] If step S 701 determines that the input buffer read address read in step S 603 agrees with the count of the pixel counter, i.e., if there is the pixel data that is an object of the address conversion process, step S 702 reads an output memory write address N 1 =0 from the pattern memory 3 and stores the pixel data in the output memory 4 at the address. Step S 703 adds 1 to the address pointer N 1 (Nx) and reads an input buffer read address N 1 =1 of the first image data from the pattern memory 3 . Step S 704 checks to see if the input buffer read address read in step S 703 is equal to the previous value N 1 =0, i.e., if the pixel data must be mapped to a plurality of addresses.
[0075] If the input buffer read address read in step S 703 is equal to the previous address N 1 =0, i.e., if the pixel data must be mapped to a plurality of addresses, step S 702 is repeated to read an output memory write address N 1 =1 from the pattern memory 3 and store the pixel data in the output memory 4 at the address.
[0076] This write operation is repeated as long as the pixel data satisfies the above-mentioned conditions. If the pixel data does not satisfy the conditions, i.e., if the pixel data that is an object of the address conversion process is not at the image converter 2 , or if step S 704 provides “No,” the subroutine SUB 00 is terminated and the flow returns to step S 604 of the main routine.
[0077] Then, the image converter 2 similarly conducts the address conversion process on the second image data in steps S 605 and S 606 . Namely, step S 605 reads a read address (input buffer read address) N 2 (initially N 2 =0) of the input buffer 9 b storing the second image data from the pattern memory 3 , and step S 606 calls the subroutine SUB 00 .
[0078] The image converter 2 repeats the above-mentioned operations for one frame, and in step S 607 , determines whether or not the count of the pixel counter is equal to “640×680−1,” i.e., if a frame of image data has arrived from each camera. If the count is not equal to “640×480−1” in step S 607 , it is determined that a frame of image data has not completely arrived yet from each camera, and the flow returns to step S 602 .
[0079] If, in step S 607 , the count is equal to “640×680−1,” it means that the output memory 4 is storing all image data to be presented for the driver. Accordingly, the bank of the output memory 4 is switched to the other, and image data of the next frame is written in the switched bank. The bank of the output memory 4 that has completely received the image data is subjected to a process of presenting images for the driver in step S 608 . The reason why the output memory 4 has two banks is to suppress the flickering of images to be presented for the driver.
[0080] FIG. 11 shows an example of input/output timing of the apparatus for converting images of vehicle surroundings according to the present invention with image data to be presented for the driver being updated frame by frame and the address conversion process being conducted pixel by pixel. In response to the synchronizing signal 20 serving as a trigger signal, the cameras 1 a and 1 b transmit each a frame of image data to the image converter 2 . The image data to be subjected to the address conversion process is NTSC digital image data that includes a vertical blanking signal portion that is not displayed on the display 5 . Accordingly, a frame processing time may differ from one frame to another depending on the contents of the pattern memory 3 . For example, there is a difference between a case that the “640×480−1”th pixel data lastly arrived from the cameras 1 a and 1 b is written into a plurality of addresses (640×480 addresses at the maximum) and a case that the same data is written nowhere. In practice, a piece of pixel data is frequently mapped to four addresses (double zoom) or nine addresses (triple zoom). Accordingly, even if the pattern memory 3 has a worst layout in terms of an input/output delay, the address conversion process will complete within the vertical blanking period, i.e., until image data of the next frame is transmitted to the image converter 2 .
[0081] A trigger to output image data to the display 5 may be the synchronizing signal 20 , or a vertical synchronizing signal multiplexed over image data of the next frame. Alternatively, the completion of storage of all image data of one frame may be a trigger to asynchronously output image data to the display 5 . One of these signals or instances may fixedly or selectively be used as a trigger.
[0082] As explained above, the apparatus of the second embodiment employs the cameras 1 a and 1 b (or a single camera) installed on a vehicle to pick up images of the surroundings of the vehicle, the image converter 2 to convert image data 10 a and 10 b from the cameras 1 a and 1 b, the input buffers 9 a and 9 b arranged for the cameras 1 a and 1 b, respectively, the pattern memory 3 to store read and write addresses, and the output memory 4 consisting of two banks. The image converter 2 outputs the synchronizing signal 20 to the cameras 1 a and 1 b. In response to the synchronizing signal 20 serving as a trigger, the cameras 1 a and 1 b output image data 10 a and 10 b to the image converter 2 . At the timing of outputting the image data 10 a and 10 b from the cameras 1 a and 1 b, the image converter 2 starts to write (a write address conversion process) pixel data of the image data 10 a and 10 b into the output memory 4 according to the write addresses. Conducting the write address conversion process on the image data 10 a and 10 b from the synchronized cameras 1 a and 1 b (or a single camera) installed on the vehicle and using the pattern memory 3 when presenting images for the driver reduce an input/output delay in the apparatus, provide the driver with images of the surroundings of the vehicle nearly in real time, and support safe driving. When changing an observing point or zooming a part of an image, the address conversion process must map a piece of pixel data to a plurality of addresses. Even in such a case, the second embodiment can reduce an input/output delay. More precisely, the second embodiment can halve an input/output delay of 2 frames (66 ms) of the related art to one frame (33 ms) at the maximum.
[0083] According to the second embodiment, the input buffers 9 a and 9 b are ring buffers that store image data in a cyclic manner. Even if the address conversion process takes a time in a zooming operation to map a pixel of image data to a plurality of addresses, no increase in the input/output delay will occur in the apparatus for converting images of vehicle surroundings because the image data from the cameras 1 a and 1 b are temporarily stored in the ring buffers and the address conversion speed of the image converter 2 is sufficiently faster than a frame rate of image data. Compared with the related art that employs two banks of memories for each camera, the embodiment can reduce the memory capacity by employing a single bank memory for each camera.
[0084] The pattern memory 3 stores read addresses of the input buffers 9 a and 9 b from which image data is read, as well as write addresses of the output memory 4 into which the image data is written, in order of pixel data of the image data to be output to the image converter 2 , i.e., in order of pixel data on which the write address conversion process is conducted. As a result, the second embodiment can carry out the write address conversion process in real time on image data successively transmitted from the cameras 1 a and 1 b.
[0085] The second embodiment employs a plurality of cameras 1 a and 1 b, and the pattern memory 3 has areas corresponding to the cameras 1 a and 1 b, respectively. Equalizing the number of memory areas to the number of groups of image data 10 a and 10 b provided by the cameras 1 a and 1 b is advantageous for the write address conversion process. It is also advantageous when combining images according to the need or liking of the driver and displaying the combined images on the display 5 .
[0086] The second embodiment writes a result of the address conversion process into the output memory 4 bank by bank. This suppresses the flickering of images presented on the display 5 for the driver.
[0087] After the completion of the address conversion process on all image data, a result of the address conversion process can be output and presented for the driver according to an optional output trigger. The output trigger may be generated by a frequency source in the apparatus for converting images of vehicle surroundings, or may be a synchronizing signal multiplexed over image data These triggers may selectively be used. In this way, the second embodiment can provide the display 5 with images according to a plurality of output triggers, to vary the timing of image presentation for the driver depending on a time necessary for the address conversion process.
[0088] The embodiments mentioned above have been presented for easy understanding of the present invention and are not intended to restrict the present invention. Accordingly, the elements disclosed in the embodiments allow design changes and equivalents without departing from the technical scope of the present invention. For example, the updating of image data to be presented for the driver may be carried out not only frame (640×680 pixels) by frame but also field (640×240 pixels) by field. The address conversion process may be carried out not only pixel by pixel but also cluster (640×1) by cluster, or image data group by image data group. It is possible to employ a plurality of pattern memories 3 having different layouts. The present invention is achievable with cameras and displays of any resolutions.
[0089] The entire contents of Japanese patent applications P2003-352278 filed Oct. 10, 2003, and P2003-402416 filed Dec. 2, 2003 are hereby incorporated by reference.
[0090] The invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. The present embodiment is therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. | An aspect of the present invention provides an apparatus for converting images of vehicle surroundings that includes, at least one camera configured to start, upon receiving a synchronizing signal, photographing the surroundings of a vehicle and outputting image data representative of the photographs, an output memory configured to store image data to be displayed on a display installed in the vehicle, a pattern memory configured to store destination addresses of the output memory, and an image converter configured to generate the synchronizing signal, obtain the image data from the camera, and transfer part or the whole of the image data to the output memory according to the destination addresses stored in the pattern memory. | 1 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a closed, but vented, receptacle constructed of good heat transfer material and partially filled (approximately one-third) with a eutectic solution. The upper portion of the interior of the receptacle includes CO 2 spray head structure for forming CO 2 snow therein and which may fall down upon the surface of the eutectic solution and the lower portion of the interior of the receptacle includes structure for pressure jet discharge of liquid CO 2 thereinto adjacent the bottom of the receptacle, the liquid CO 2 flow capacity of the pressure jet discharge structure and the lower portion of the interior of the receptacle being appreciably more than the liquid CO 2 flow capacity of the CO 2 spray head structure and the jet discharge structure being arranged to effect a circulatory movement of the solution within the tank including generally opposite longitudinal and generally opposite vertical improvements of movement.
2. Description of Related Art
Many enclosed containers heretofore have been provided into which liquid CO 2 may be spray discharged for forming CO 2 snow within the containers. In addition, cooling containers for chilled eutectic solutions also have been provided as well as cooling containers having transfer passages formed therein. However, the cold tank of the instant invention provides a closed container (but having its upper portion vented to the exterior) to be partially filled with a eutectic solution and into whose upper portion liquid CO 2 may be spray discharged for forming snow within the receptacle upper portion, the snow falling down within the receptacle onto the surface of the eutectic solution. Further, the container also includes spray jet discharge structure within a lower portion thereof below the surface of the eutectic solution through which an appreciably larger quantity of liquid CO 2 may be discharged into the eutectic solution, the spray discharge of liquid CO 2 into the eutectic solution being rapidly transformed into CO 2 snow for suspension in and chilling the eutectic solution as well as a small quantity of CO 2 gas which may rise through the eutectic solution to the surface thereof.
The injection of liquid CO 2 into the eutectic solution causes sufficient circulation of the eutectic solution within the lower portion of the receptacle to cause the snow falling to the surface of the solution to be blended therein, thereby more rapidly chilling the eutectic solution down to a point elevated only slightly above its freezing point.
By this method, the heat absorbing capacity of a given amount of liquid CO 2 is increased over presently known and used methods of chilling a cold tank or the like.
SUMMARY OF THE INVENTION
The cold tank of the instant invention is approximately one-third filled with a eutectic solution comprising, for instance, a 3:1 mixture of water and propylene glycol having a freezing temperature of approximately -20° F. Liquid CO 2 is spray discharged into the upper portion of the interior of the receptacle above the level of eutectic solution therein while at the same time liquid CO 2 is injected into a lower portion of the interior little receptacle below the eutectic level.
By using this method of chilling a cold tank an appreciably greater heat absorbing capacity is obtained through the use of the same amount of liquid CO 2 and the tank and solution are more rapidly chilled.
The main object of this invention is to provide a more efficient cold tank.
Another object of this invention is to provide a more efficient cold tank which may be produced as a totally new product or a retrofitted older and less efficient cold tank.
Another object of this invention is to provide a cold tank of improved operation and which may incorporate otherwise old and operationally dependable cold tank structure.
A final object of this invention to be specifically enumerated herein is to provide a cold tank in accordance with the preceding objects and which will conform to conventional forms of manufacture, be of simple construction and dependable in operation so as to provide a device which will be economically feasible, long-lasting and relatively trouble free in operation.
These together with other objects and advantages which will become subsequently apparent reside in the details in construction and operation as more fully hereinafter described and claimed, reference being had to the accompanying drawings forming a part hereof, wherein like numerals refer to like parts throughout.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a cold tank constructed in accordance with the present invention;
FIG. 2 is an enlarged fragmentary transverse vertical sectional view taken substantially upon a plane indicated by the section line 2--2 of FIG. 1; and
FIG. 3 is a vertical sectional view taken substantially upon the plane indicated by the section line 3--3 of FIG. 2.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now more specifically to the drawings the numeral 10 generally designates a cold tank constructed in accordance with the present invention.
The cold tank 10 includes large area opposite side walls 12 and 14 and smaller area opposite end walls 16 and 18. The end walls 16 and 18 interconnect corresponding ends of the side walls 12 and 14 and the latter include vertically extending corrugations to increase the surface area thereof. Further, top and bottom walls 20 and 22 extend between and interconnect the upper marginal portions of the walls 12, 14, 16 and 18.
The interior of the tank 10 is approximately one-third filled with any suitable eutectic solution 24 and the lower portion of the tank 10 includes transversely extending heat exchange air-flow tubes 26 extending between and sealingly secured through the side walls 12 and 14.
A liquid CO 2 header pipe 28 is disposed in the upper portion of the tank 10 and extends longitudinally thereof. The header pipe 28 opens through the end wall 16 from a suitable supply of liquid CO 2 under pressure. Further, a CO 2 supply line for pipe 30 enters into the upper portion of the interior of the tank 10 through the end wall 18 and is immediately directly downwardly as 32 to a position closely adjacent the bottom wall 22. The lower end of the supply line 30 includes a horizontally directed terminal end 34 and the terminal end 34 terminates in an end fitting 36 including a plurality (four) of small diameter outlet openings 38 formed therein. The supply line 30 receives its liquid CO 2 from the same supply (not shown) thereof to which the header pipe 28 is connected. The supply (not shown) of liquid CO 2 is under approximately 300 pounds pressure per square inch.
The header pipe 28 includes a plurality of downwardly directed discharge lines 40 spaced therealong and each discharge line 40 is communicated with one or more spray discharge outlets 42 disposed within a downwardly opening horn 44. Spray discharge of liquid CO 2 under pressure from the outlets 42 results in CO 2 snow being formed within the horns 44 and dropping downwardly onto the surface of the eutectic solution 24. In addition, spray discharge of liquid CO 2 from the outlet openings 38 results in some of the discharged liquid CO 2 being directly converted into CO 2 snow while the remaining amount of discharged CO 2 is transformed into CO 2 gas. In any event, a circulatory motion such as that indicated at 50 in FIG. 3 is caused within the lower third of the tank 10 containing the eutectic solution 24.
Conventionally, CO 2 snow may be discharged on top of a chilled eutectic solution and in some instances it is believed that CO 2 may have been spray discharged into a chilled eutectic solution for cooling thereof.
The cooling tank 10 is primarily designed to be used in insulated truck bodies (although the tank 10 may be exteriorly mounted) and a certain amount of time is required together with a certain amount of liquid CO 2 in order to fully chill the tank 10 and the eutectic solution 24.
By the instant invention, the amount of time required is substantially reduced and the amount of liquid CO 2 required is appreciably reduced. By jet discharging liquid CO 2 from the outlets 38, the circulatory movement 50 of the eutectic solution 24 is created and at the same time CO 2 snow formed in the horns 44 drops down upon the surface of the eutectic solution 24. The circulatory movement 50 is such that the snow dropping down upon the surface of the eutectic solution 24 is circulated through the lower portion of the tank 10 with the circulating eutectic solution 24 thus more quickly chilling the eutectic solution 24 and minimizing the build up of the snow on top of the surface of the eutectic solution 24.
Also, when the eutectic solution 24 has been sufficiently chilled to form a slush-like mixture, the desired chilling operation is almost completely accomplished and the discharge of liquid CO 2 from the outlets 38 is automatically slowed by the resistance of the slush-like mixture against which the liquid CO 2 is being discharged through the outlets 38. At this point, snow will begin to build up on the surface of the eutectic solution 24 and the supply of liquid CO 2 to the cooling tank 10 soon must be terminated.
If the liquid CO 2 is discharged only into the eutectic solution 24, soon after the eutectic solution 24 forms a slush-like mixture (as it approaches its freezing temperature) the line pressure within the line 30 will build up due to the resistance of the discharge of liquid CO 2 against the slush-like mixture through the outlet opening 38. This build up of line pressure can cause portions of the line 30 to rupture. Accordingly, when the same supply of liquid CO 2 is utilized to supply the line 30 and the header pipe 28, even though the resistance to the discharge of liquid CO 2 from the outlet opening 38 is increased, the liquid CO 2 from the aforementioned pressurized supply thereof may still experience pressure relief through the spray outlets 42, thereby preventing rupture of the supply line 30 in the event a person controlling the valves supplying liquid CO 2 to the header pipe 28 and the supply line 30 is inattentive to his job at the time the eutectic solution 24 reaches the aforementioned slush-like condition.
Accordingly, by discharging CO 2 snow onto the surface of the eutectic solution 24 during primary cooling thereof as a result of liquid CO 2 being discharged directly into the eutectic solution 24 from the outlet opening 38, the chilling action on the eutectic solution 24 is accelerated (resulting in a considerable savings of time) and the danger of rupture of the supply line 30 is substantially eliminated as a result of an inattentive person controlling the valve structure through which liquid CO 2 is supplied to the header pipe 28 and the supply line 30.
The tubes 26 are not in themselves novel, but they increase the surface area for cooling purposes and more importantly, brace the side walls 12 and 14 relative to each other in order to prevent a build up of pressure within slush-like eutectic solution being sufficient to outwardly bow the side walls 12 and 14 before the supply of liquid CO 2 to the tank 10 is terminated. Accordingly, although the overall tank construction of the instant invention is generally similar to the tanks disclosed in my prior U.S. Pat. Nos. 4,404,818 and 4,502,293 (the latter patent disclosing the equivalent of the tubes 26), the tubes 26 perform a dual function in the instant invention, the upper portion of the interior of the tank 10 being vented as at 54.
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 vented cold tank is provided and partially filled with a eutectic solution. CO 2 snow forming structure is provided within the interior of the tank above the level of the eutectic solution therein and liquid CO 2 injection means is provided in a lower portion of the tank below the level of eutectic solution and arranged to create circulation of the eutectic solution within the tank including generally opposite horizontal and generally opposite vertical component of movement of the solution within the tank. Further, structure is provided for communicating the CO 2 snow forming means and the liquid CO 2 injection means with the same source of liquid CO 2 under pressure. | 5 |
This is a Divisional of U.S. Ser. No. 07/204,140 filed June 8, 1988, now abandoned which is a Divisional of U.S. Ser. No. 06/767,202, now U.S. Pat. No. 4,772,606, filed Aug. 22, 1985, which is a Continuation-In-Part of U.S. Ser. No. 06/660,152, filed Oct. 12, 1984, now abandoned.
BACKGROUND OF THE INVENTION
8-Aminoguanine, a compound known since the turn of the century, has been reported to have PNP-activity by R. Parks, et. al., in Biochem. Pharm., 31 (2), 163 (1982).
9-(2-Furfuryl)guanine is a known compound described in J. Am. Chem. Soc., 81, 3046 (1959) having no disclosed utility. The present invention is related to novel purine derivatives not obvious to an ordinarily skilled artisan, particularly, 9-heteroaryl guanines as having PNP-inhibiting activity.
8-Amino-9-benzylguanine was discussed at the 16th Annual Graduate Student Meeting in Medicinal Chemistry, University of Michigan, Ann Arbor, Mich. However, the present compounds are not obvious from either the synthesis or biological activity of 8-amino-9-benzylquanine discussed.
With regard to various novel processes of the present invention Ji-Wang Chern, et al, describe "A Convenient Synthesis of 2-N-methoxycarbonylaminooxazolo[5,4-d]pyrimidines" in J. Het. Chem. 21, 1245-6 (1984). A similar synthesis is described by S. Ram, et al, in "A Synthesis of Carbamic Acid[Imidazo-Heteroaromatic]Methyl Ester Derivatives Using Methoxycarbonyl Isothiocynate," Heterocycles, Vol. 22, No. 8, 1984, pp 1789-90, in which methoxycarbonyl isothiocyanate is used in a one pot reagent for the ring closure of an o-diaminopyrimidine derivative to afford a purine derivative possessing the methoxycarbonylamino functionality at position eight. Further, the mechanism of these two synthesis is discussed by Ji-Wang Chern, et al, in "The Novel Ring Opening of an Oxazolo[5,4-d]Pyrimidine and Subsequent Rearrangement to Form an Imidazo[4,5-d]Pyrimidine," Heterocycles, Vol. 22, No. 11, 1984, pp 2439-2441. None of the disclosures include a disclosure of reaction conditions, or an Ar as a heteroaryl or substituted heteroaryl, substituent defined hereinafter for the compound of Formula I prepared by the novel processes of the present invention. That is, corresponding Ar groups as defined hereinafter for each of the novel intermediates III, II, and I to be heteroaryl or substituted heteroaryl are not included in the above references and furthermore are not obvious variants thereof.
SUMMARY OF THE INVENTION
The present invention relates to a compound of the formula ##STR1## wherein R 1 is OH or SH; R 2 is hydrogen, NHR in which R is hydrogen or COR 6 where R 6 is alkyl of one to four carbon atoms, aryl or arylalkyl; R 3 is hydrogen, hydroxyl, mercapto, bromine or NHR where R is hydrogen or COR 6 wherein R 6 is as defined above; n is zero or one; m is zero, one, two, or three, with the proviso that m or n is at least one; R 4 and R 5 are each independently hydrogen, alkyl of one to four carbon atoms, hydroxyalkyl of one to four carbon atoms, aryl, arylalkyl or cycloalkyl of three to six carbon atoms, and Ar is heteroaryl or heteroaryl substituted by alkyl, alkoxy of one to four carbon atoms, --C═C--C═C-- attached to adjacent carbons so as to form a benzo radical, or halogen; or a pharmaceutically acceptable acid or base addition salt thereof, excluding the compound wherein R 1 is OH, R 2 is amino, R 3 is hydrogen, n is zero, m is one, and A r is 2-furanyl, i.e., 9-(2-furanylmethyl)guanine.
The present invention includes a method of manufacture and a pharmaceutical composition comprising an effective amount of a compound of the Formula I with a pharmaceutically acceptable carrier, as well as a method of treatment of autoimmune diseases such as arthritis, systemic lupus erythematosus, inflammatory bowel diseases, multiple sclerosis, juvenile diabetes, as well as transplantation, viral infections and cancer by administering an effective amount of a compound of the Formula I in unit dosage form to a host of the disease That is, the amount is the amount effective for treating each of the autoimmune diseases. It is understood, an ordinarily skilled physician would begin with a less than effective amount for treatment and increase the dose until the desired effect is obtained exercising care to administer an amount less than the amount toxic to the host of the disease.
Both the above pharmaceutical composition and method of treatment include as active ingredient 9-(2-furfuryl)guanine.
The present invention also includes the novel intermediates as follows:
(1) A compound of Formula III wherein R 6 is alkyl of one to four carbon atoms, aryl, or arylalkyl; n is zero or one; m is zero, one, two, or three, with the proviso that m or n is at least one; R 4 and R 5 are each independently hydrogen, alkyl of one to four carbon atoms, aryl, arylalkyl, or cycloalkyl of three to six carbon atoms, hydroxyalkyl of one to four carbon atoms, aryl, arylalkyl, or cycloalkyl of three to six carbon atoms, hydroxyalkyl of one to four carbon atoms, and Ar is heteroaryl or heteroaryl substituted by alkyl of one to four carbon atoms, alkoxy of one to four carbon atoms or halogen;
(2) a compound of Formula II wherein R 6 , n, m, R 4 , R 5 , and Ar are as defined above; and
(3) a compound of Formula IV wherein n, m, R 4 , R 5 , and Ar are as defined above.
Additionally, the novel processes of the present invention are as follows:
(A) A novel process for the preparation of a compound of Formula I, wherein R 1 is OH or SH, R 2 is NHR wherein R is as defined above, R 3 is hydrogen, hydroxyl, mercapto, bromine, or NHR where R is hydrogen or COR 6 wherein R 6 is as defined above, L and n, m, R 4 , R 5 , and Ar are also as defined above which comprises heating a compound of the Formula III wherein R 6 , n, m, R 4 , R 5 , and Ar are as defined above to obtain the compound of Formula I wherein R 1 is OH and R 3 ' is NHCOOR 6 wherein R 6 is as defined above, and if desired, converting said compound to a compound where R 1 is S or SH by methods analogous to those known in the art, and if further desired, where R 3 ' is NHCOOR 6 converting the compound to a compound where R 3 is hydrogen, or NHR where R is hydrogen or COR 6 wherein R 6 is as defined above also by known methods.
Particularly, the above process is for the preparation of 8-amino-9-[(2-thienyl)methyl]quanine.
(B) A process for the preparation of a compound of the formula ##STR2## wherein R 1 , R 2 , R, R 3 , R 4 , R 5 , m, n, and Ar are as defined above, with the proviso that R 3 is not Br, and R 3 is not NHR; which comprises reacting a compound of the formula ##STR3## with formic acid and formamide at elevated temperatures, to obtain a compound of the formula ##STR4## and, if desired, converting by methods analogous to those known in the art the compound into a compound of Formula I wherein R 1 is SH and/or R 3 is hydroxyl, mercapto, or NHR wherein R is as defined above or a pharmaceutically acceptable acid addition or base salt thereof.
(C) A process for the preparation of a compound of the formula ##STR5## which comprises treating a compound of the formula ##STR6## with N-bromosuccinimide in an organic solvent, and, if desired, converting by methods known in the art the resulting compound into a pharmaceutically acceptable acid addition or base salt thereof.
(D) A process for the preparation of a compound of the Formula I wherein R 3 is NHR wherein R is as defined above; which comprises reacting a compound of the formula ##STR7## wherein R 1 , R 2 , R 4 , R 5 , n, m, and Ar is as defined above; with hydrazine at elevated temperatures and, optionally, with Raney nickel in an alcohol solvent, and, if desired, converting the resulting compound where R is hydrogen to a compound where R is COR 6 with an alkanoyl halide, aroyl halide, or arylalkanoyl halide in the presence of an organic base, and, if desired, where R 1 is O or OH, converting said compound to a compound where R 1 is S or SH by known methods, and, if further desired, converting the resulting compound by methods analogous to those known in the art to a pharmaceutically acceptable acid addition or base salt thereof.
(E) A novel process for the preparation of a compound of Formula III wherein R 6 , n, m, R 4 , R 5 , and Ar are as defined above which comprises contacting a compound of the Formula II wherein R 6 , n, m, R 4 , R 5 , and Ar are as defined above, with a coupling agent in the presence of a solvent to obtain the compound of Formula III.
The coupling agent of the process is preferably N,N'-dicyclohexylcarbodiimide. The preferred solvent is anhydrous dimethylformamide.
(F) A novel process for the preparation of a compound of Formula II wherein R 6 , n, m, R 4 , R 5 , and Ar is as defined above which comprises refluxing a compound of Formula IV wherein n, m, R 4 , R 5 , and Ar are as defined above in anhydrous methanol with anhydrous HCl then basified and treated with lower alkoxy carbonyl isothiocyanate to obtain the compound of Formula II.
(G) A novel process for the preparation of a compound of Formula IV wherein n, m, R 4 , R 5 , and Ar are as defined above which comprises:
step (1) reacting 2-amino-6-chloro-4-pyrimidinol in methoxyethanol with arylalkylamine in the presence of triethylamine;
step (2) then treating the product of step (1) with aqueous sodium nitrite, step (3) reducing the product of step (2) with sodium dithionite in formamide and 90% formic acid to obtain the compound of Formula IV.
Under certain circumstances it is necessary to protect either the N or O of intermediates in the above noted process with suitable protecting groups which are known. Introduction and removal of such suitable oxygen and nitrogen protecting groups are well known in the art of organic chemistry; see for example, (1) "Protective Groups in Organic Chemistry," J. F. W. McOmie, ed., (New York, 1973), pp 43ff, 95ff; (2) J. F. W. McOmie, Advances in Organic Chemistry, Vol. 3, 191-281 (1963); (3) R. A. Borssonas, Advances in Organic Chemistry, Vol. 3, 159-190 (1963); and (4) J. F. W. McOmie, Chem. & Ind., 603 (1979).
Examples of suitable oxygen protecting groups are benzyl, t-butyldimethylsilyl, methyl, isopropyl, ethyl, tertiary butyl, ethoxyethyl, and the like. Protection of an N-H containing moiety is necessary for some of the processes described herein for the preparation of compounds of this invention. Suitable nitrogen protecting groups are benzyl, triphenylmethyl, trialkylsilyl, trichloroethylcarbamate, trichloroethoxycarbonyl, vinyloxycarbamate, and the like.
Under certain circumstances it is necessary to protect two different oxygens with dissimilar protecting groups such that one can be selectively removed while leaving the other in place. The benzyl and t-butyldimethylsilyl groups are used in this way; either is removable in the presence of the other, benzyl being removed by catalytic hydrogenolysis, and t-butyldimethylsilyl being removed by reaction with, for example, tetra-n-butylammonium fluoride.
In the process described herein for the preparation of compounds of this invention the requirements for protective groups are generally well recognized by one skilled in the art of organic chemistry, and accordingly the use of appropriate protecting groups is necessarily implied by the processes of the charts herein, although not expressly illustrated.
The products of the reactions described herein are isolated by conventional means such as extraction, distillation, chromatography, and the like.
The salts of compounds of Formula I described above are prepared by reacting the appropriate base with a stoichometric equivalent of the acid compounds of Formula I to obtain pharmacologically acceptable salts thereof.
The compounds of this invention may also exist in hydrated or solvated forms.
The above novel processes beginning with (G) and proceeding through (F), and (E), or to and including OH and R 3 ' is NHCOOR 6 wherein R 6 is as defined above may be conducted in a one pot reaction.
Further, the lower alkoxy carbonylisothiocyanate may itself be added in the novel process (F) above or prepared in situ by suspending potassium thiocyanate in acetonitrile and adding methyl chloroformate to the suspension for a mixture which is heated at reflux in the presence of the basified hydrochloride salt of Formula I in the above process (F).
DETAILED DESCRIPTION
The compounds of Formula I and intermediates of Formula II and IV of the present invention exist in tautomeric forms as purines or guanines as illustrated below. Both forms are included as part of the invention and are indiscriminately described in the specification. ##STR8##
The term "alkyl of one to four carbon atoms" means a straight or branched hydrocarbon chain up to four carbon atoms such as, for example, methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl or tertiarybutyl. "Hydroxyalkyl of one to four carbon atoms" means the same alkyl radical with a terminal hydroxyl group.
The term "aryl" includes an unsubstituted or substituted aromatic ring suchas, phenyl or phenyl substituted by halogen, e.g., fluorine, chlorine, bromine, or iodine, alkyl of one to four carbon atoms, such as methyl or ethyl, hydroxy, alkoxy of one to four carbon atoms, such as methoxy or ethoxy, or trifluoromethyl.
The term "arylalkyl" means an aromatic ring attached to an alkyl chain of up to four carbon atoms, such as unsubstituted or substituted phenylethyl or benzyl where the substituents on the aromatic ring may be the same as defined above.
The term "heteroaryl" means five- or six-membered aromatic ring containing one or more heteroatoms, such as nitrogen, oxygen and sulfur. Preferred radicals are the 2- or 3-furanyl; 2- or 3-thienyl; the 2-, 3- or 4-pyridyl; or 2-, 4-, or 5-thiazolyl radicals.
Pharmaceutically acceptable acid addition salts are those derived from inorganic acids such as hydrochloric, sulfuric and the like, as well as organic acids such as methanesulfonic, toluenesulfonic, tartaric acid, andthe like. These salts may also be prepared by standard methods known in theart.
Pharmaceutically acceptable base salts are those derived from inorganic bases such as sodium hydroxide, potassium hydroxide or ammonium hydroxide or organic bases such as arginine, N-methyl glucamine, lysine and the like. These salts may also be prepared by standard methods known in the art.
A preferred embodiment of the present invention is a compound of Formula 1 wherein R 1 is OH or SH; R 2 is hydrogen or NH2; R 3 is hydrogen, bromine or NH2; n is zero or one; m is zero or one, where n or mmust be one; R 4 and R 5 are each independently hydrogen, alkyl of 1-4 carbon atoms or hydroxyalkyl of one to four carbon atoms, and Ar is 2-or 3-furanyl, 2- or 3-thienyl, or 2-, 3- or 4-pyridyl, or 2- or 3-furanyl, 2-, 4-, or 5-thiazolyl, 2- or 3-thienyl, or 2-, 3-, or 4-pyridyl substituted by alkyl of one to four carbon atoms, or a pharmaceutically acceptable acid addition base salt.
Another preferred embodiment of the present invention is a compound of Formula 1 wherein R 1 is OH; R 2 is NH2; R 3 is hydrogen, bromine or NH2; n is O or 1; m is O or 1, where n or m must be 1, and A r is 2- or 3-furanyl, 2- or 3-thienyl, 2-, 4-, or 5-thiazolyl, or 2-, 3- or 4-pyridyl, or 2- or 3-furanyl, 2- or 3-thienyl, 2-, 4-, or 5-thiazolyl, or 2-, 3-, or 4-pyridyl substituted by methyl or ethyl, or a pharmaceutically acceptable acid addition or base salt.
Particular embodiments of the present invention include:
9-[(3-pyridyl)methyl]guanine;
9-(2-thenyl)guanine;
9-[(2-pyridyl)methyl]guanine;
9-[(5-ethyl-2-thienyl)methyl]guanine;
8-bromo-9-(2-thienylmethyl)guanine;
8-bromo-9-(5-ethyl-2-thenyl)guanine;
8-bromo-9-(2-furfuryl)guanine;
8-bromo-9-[(3-pyridyl)methyl]guanine;
8-amino-9-(5-ethyl-2-thenyl)guanine;
8-amino-9-(2-thienylmethyl)guanine, and
8-amino-[9-(3-pyridyl)methyl]guanine.
The most preferred compound is 8-amino-9-(2-thienylmethyl)guanine .
The 8-bromo compounds are not only useful pharmacologically but are also useful as intermediates for preparing certain compounds of the present invention.
The compounds of Formula I may be prepared according to Methods B, A, and/or C as shown in the following Schemes 1, 2, and 3, respectively
Generally, Method A is preferred. ##STR9##
II. Method B-Discussion
Compounds of Formula 8 above may also be used as starting materials and maybe prepared by reacting 2-amino-6-chloro-4-hydroxy-5-nitropyrimidine, the compound of formula 2 described in J. Chem. Soc., 1962, p. 4186, with the appropriate heteroaryl (alkyl) amine of formula 3 in the presence of an organic base at elevated temperatures. The resulting compound of the formula 4 is then treated with sodium dithionite and formic acid followed by further treatment with formic acid and formamide at elevated temperatures to afford the compound of Formula 8.
Alternative, starting materials of Formula 8 may be prepared according to amodified method of C. W. Noelland, R. K. Robins in J. Med. Chem., 5, 558, (1962) starting with a compound of the Formula 5 which is reacted with an appropriate heteroaryl alkyl amine of Formula 3, then with nitrous acid toform the 5-nitrosopyrimidine, 6, which is reduced and ring closed by treatment with sodium dithionite, formic acid and formamide as described above.
The heteroaryl (alkyl) amines of Formula 3 are either commercially available or may be prepared by known methods.
Treatment of a compound of Formula 8 with N-bromosuccinimide in acetic acid, dimethylformamide or methanol produces a compound of Formula 1a which when treated with hydrazine hydrate gives the hydrazine or directly the 8-amino derivative of Formula 1b. The reaction of the 8-bromo compoundwith hydrazine may or may not proceed entirely to the 8-amino compound. Thus when the 8-hydrazine compound is obtained, it may be further reacted with Raney nickel to allow the reduction to go to completion and afford the desired 8-amino compound. Compounds of formula 1b may be further converted by known methods to provide R 6 substituents of formula 1d or, where R 1 is O, converting said compound to a compound of formula 1c where R 1 is S by reacting the said compound with P 2 S 5 in presence of a base such as pyridine (examples given). ##STR10##
Generally, the processes of the present invention as shown in Scheme 2 above are as follows.
A 2-amino-6-chloro-4-pyrimidinol, that may be in the monohydrate form, is suspended in methoxyethanol, in the presence of excess amine or an organicbase such as triethylamine. The compound of Formula XXX having n, m, R 4 , R 5 , and Ar as defined above is added to the suspension and heated optimally to a temperature at which the suspension refluxes. Refluxing is continued until thin layer chromatography, for example, with 20% methanol in methylene chloride, shows the reaction producing a compound of Formula XX wherein n, m, R 4 , R 5 , and Ar are as defined above is complete.
The reaction mixture having the compound of Formula XX is then diluted withwater and treated with sodium nitrite in the presence of acetic acid. A nitroso of the Formula X again having n, m, R 4 , R 5 , and Ar as defined above is obtained from the treatment by the nitrite as evidenced by a color change and precipitate. The temperature of the treatment is at about room temperature.
The treatment mixture having therein the nitroso of Formula X is contacted with sodium dithionite in a solvent mixture such as formamide, formic acid, at a temperature of from 60°-90° C., preferably from 70°-80° C. The temperature is then raised to the boiling point of the solvent mixture, approximately 130°-140° C. forup to an hour, preferably at least 20 minutes, or when the color of the nitroso containing mixture described above disappears and an inorganic salt precipitates. The product of this contact is a compound of the Formula IV wherein n, m, R 4 , R 5 , and Ar are as defined above.
Subsequently, the compound of Formula IV is dried and suspended in an anhydrous solvent such as methanol, ethanol, and the like. The suspension is then treated with a dry acid such as HCl, to form the acid salt shown as Formula IVa, wherein n, m, R 4 , R 5 , and Ar are as defined above, or salt corresponding to the acid used for the treatment.
The salt IVa is basified with a concentrated mixture of NH 4 OH and 97%hydrazine to obtain a base of the Formula IVb wherein n, m, R 4 , R 5 , and Ar are as defined above. The base is unstable, however, is dried, for example in a vacuum over P 2 O 5 .
The dried free base IVb is added to a solution of R 6 OOCNCS wherein R 6 is as defined above. The solution of R 6 OOCNCS may be prepared by suspending potassium thiocyanate in a solvent such as acetonitrile and treating with slightly less than an equivalent of ClCOOR 6 wherein R 6 is as defined above at reflux for about one hour, cooled, then stirred to insure all of the alkylchloroformate is reacted before the base IVb is added. The reaction of dried free base IVb with the R 6 OOCNCS is monitored to completion with thin-layer chromatography using silica in 20% methanol in methylene chloride to obtain a compound of Formula II wherein R 6 , n, m, R 4 , R 5 , and Ar is as defined above.
A mixture of the compound of Formula II and a coupling agent such as N,N'-dicyclohexylcarbodiimide, in a solvent such as anhydrous dimethylformamide, is stirred at about room temperature until completion of the reaction is shown by thin layer chromatograph to yield a compound of Formula III wherein R 6 , n, m, R 4 , R 5 , and Ar are as defined above.
The reaction mixture having the compound of Formula III and anhydrous potassium carbonate are suspended in a solvent such as anhydrous methanol,and refluxed until thin layer chromatography shows the reaction producing acompound of Formula I wherein R 1 is O or OH, R 3 ' is NHCOOR 6 , wherein R 6 is as defined above and n, m, R 4 , R 5 , and Ar are as defined above.
The compound of Formula I wherein R 1 , is O and OH and R 3 ' is NHCOOR 6 may then, if desired be used to produce by known methods a compound of Formula I wherein R 3 is NHR wherein R is as defined aboveother than COOR 6 .
Likewise, a compound of Formula I wherein R 1 is S or SH may be prepared by known methods from the compounds of Formula I wherein R 1 is O or OH.
The preparation of compounds IV, II, III, and I may be carried out in one pot. However, separation and purification of each of the compounds IV, II,III, or I may be effected by conventional methods, if desired.
Generally the processes of the present invention as shown in Scheme 3 - Method C above are as follows:
A mixture of 2-amino-6-chloropurine, potassium carbonate, and the starting material of the formula shown as 2 in Scheme 3 - Method C, that is generally commercially available or can be prepared by methods analogous to those known in the art, are stirred under nitrogen for from about 2 to 48 hours. A mixture of 7- and 9- substituted chloropurines shown as Formula 4 and Formula 5 in Scheme 3 - Method C are obtained The desired compound of Formula 4 is separated and treated with an aqueous acid such as HCl followed by addition of a weak solution of a base such as NaOH. Themixture is heated to assure it is neutralized followed by conventional separation of the desired product of Formula I wherein R 3 is hydrogen. Subsequently, reactions to produce compounds of Formula 7 and Formula 8 as shown in Scheme 3 - Method C are described above for corresponding steps in Scheme I - Method B.
The compounds of the present invention have been shown to exhibit significant enzyme inhibition activity and cytotoxic activity. In the purine nucleoside phosphorylase (PNP-4) enzyme assay, total inhibition wasachieved at a concentration less than about 300 micromoles on certain compounds of the present invention. PNP-4 activity was measured radiochemically by measuring the formation of [ 14 -C]-hypoxanthine from [ 14 -C]inosine [Biomedicine, 33, 39 (1980)] using human erythrocyte as the enzyme source. The same compounds also were found by a standard test (HTBA-1) [Science, 214, 1137, (1981)] to be selectively cytotoxic for T-cells in the presence of 2'-deoxyguanosine at a similar concentration range and nontoxic to B-cell in the presence of the same amount of 2'-deoxyguanosine. Representative examples are shown in the activity table.
______________________________________Activity TableEx- Method HTBA-1ample of PNP-4 T-Cell +dGuoNum- Prepara- IC.sub.50 (10 μM)ber Ar.sup.1 tion (μM) IC.sub.50 (μM)______________________________________1 3-Py B 21.9 54.12 or 9a 2-Th A or B 0.17 0.833 2-Th-5-Et B 0.93 4.159b 2-Fu B or A 0.25 2.579c 3-Th A, B, 0.085 0.49 or C9d 2-Th-3-CH.sub.3 B 4.05 8.616Ad 3-TH-2-CH.sub.3 A 1.72 18.216Ac CH.sub.2 -2-Th A 6.25 17.616Ak 3-TH-5-CH.sub.3 A 0.63 2.816Ag ##STR11## A 8.45 >12.59e ##STR12## B 14016Ae 2-Th-5-Me A16Af 2-Py A 4.6______________________________________ .sup.1 Py = pyridine, Th = thiophene, Fu = furan
Since T-cells play a central role in immune response, use of the compounds of the invention is contemplated for the immunoregulation of autoimmune disease such as rheumatoid arthritis, systemic lupus erythematosus, inflammatory bowel disease, multiple sclerosis, myasthemia gravis, transplantation, juvenile diabetes, cancer, and viral diseases. The present invention thus includes compositions containing a compound of Formula I in treating disease such as autoimmune disease characterized by abnormal immune response in warmblooded animals. According to this aspect of the invention, the properties of the compounds of the invention are utilized by administering to a warmblooded animal an effective amount of apharmaceutical composition containing as the active ingredient at least about 0.1 percent by weight, based on the total weight of the composition of at least one such compound of the invention.
Pharmaceutical compositions of the invention can be formulated in any suitable way, preferably with an inert carrier for administration orally, parenterally, ophthalmically, topically, or by suppository.
For example, the compounds of the present invention are formulated into dosage forms such as tablets or syrups by blending with an inert pharmaceutical carrier such as lactose or simple syrup by methods well known in the art. For injectable dosage forms, they are formulated with vehicles such as water, propylene glycol, peanut oil, sesame oil, and the like. In these dosage forms, the active ingredient is from about 0.05 grams to 0.5 grams per dosage unit.
The present invention is further illustrated by way of the following examples.
EXAMPLE 1
9-[(3-Pyridinyl)methyl]guanine
3-Pyridylmethylamine (15.8 ml; 0.1517 mole) was added to a suspension of 2-amino-6-chloro-4-hydroxy-5-nitropyrimidine (14.45 g; 0.0758 mol) in isopropanol (600 ml). The mixture was heated under reflux for two hours and then stirred overnight at room temperature when the product, 2-amino-4-hydroxy-6-[(3-pyridyl)methylamino]-5-nitropyrimidine, crystallized out. The product was filtered, washed with water, and air dried.
The crude nitropyrimidine (25.32 g) from above was suspended in formamide (150 ml) and 90% formic acid (50 ml) and the suspension was warmed to 70° C. in a water bath. Sodium dithionite was carefully added to the warm suspension and then boiled for 15-20 minutes. The reaction mixture was diluted with hot water (300 ml), treated with charcoal and then boiled for an additional 20-25 minutes, filtered through celite, cooled and concentrated under reduced pressure to give formamido-pyrimidine which was collected by filtration, washed with acetone, and dried under vacuum at 56° C.
The above product was resuspended in formamide (100 ml) and formic acid (8 ml) and was heated under reflux for 3.5 hours, poured onto 400 ml ice-water and then filtered. Two crystallization from boiling water gave the analytical sample of the desired product (4.5 g) mp>300° C.
EXAMPLE 2
The procedure described in Example 1 was repeated to prepare the following 9-(heteroaryl or substituted heteroaryl)methyl guanines, starting from appropriate heteroaryl or substituted heteroaryl methylamines. 9-(2-Thienylmethyl)guanine, mp>300° C. 9-[(2-Pyridinyl)methyl]guanine, mp>300° C. 9-(2-Furanylmethyl)guanine, mp 296°-299° C., dec. (Known Compound: J. Am. Chem. Soc., 1959, 81:3046.) 9-[(3-methyl-2-thienyl)methyl]guanine, mp>290° C. (dec). 9-[(2-methyl-3-thienyl)methyl]guanine, mp>270° C. (dec). 9-[(benzo[b]thien-3-yl)methyl]guanine, mp>300° C. (dec). 9-(3-thienylmethyl)guanine, mp 320°-322° C. (dec).
EXAMPLE 2A 2-Amino-9-[(2-thienyl)methyl]-6-chloropurine
A mixture of 2-amino-6-chloropurine (Aldrich Chemical Co.) (7.47 g; 0.44 mol), potassium carbonate (6.64 g; 0.048 mol), and 3-thenylbromide (see U.S. Pat. No. 3,746,724) (7.8 g; 0.044 mol) in DMF (200 ml) was stirred under nitrogen at room temperature for 48 hours. The mixture was filtered and the filtrate evaporated to dryness under vacuum, ethyl ether was addedand the precipitate was collected by filtration to give a mixture of 7- and9-substituted chloropurines. A sample of pure 9isomer was prepared by chromatography on silica gel with 5% methanol/methylene chloride as the eluting solvent to separate it from the 7-isomer. Analytical sample was obtained by crystallization from acetonemethanol mixture, yield 2.36 g, mpsoftens at 185° C. (dec) and then melts at 203°-204° C. (dec).
EXAMPLE 2B
The procedure described in Example 2A was repeated to prepare the following2-amino-9-[(heteroaryl or substituted heteroaryl)methyl]-6-chloropurines, starting from appropriate heteroaryl or substituted heteroaryl methylhalides.
2-Amino-9-[(2,5-dimethyl-3-thienyl)methyl]-6-chloropurine, mp 190°-192° C. (starting material 2,5-dimethyl-3-thenyl chloride was prepared according to the lit. procedure; Buu-Hoi and Nguyen-Hoan, Rec. Trav. Chim, 1949, 68:5).
2-Amino-9-(3-furanylmethyl)-6-chloropurine (starting material 3-furfurylchloride was prepared according to lit. procedure; S. P. Tanis, Tet. Letts., 1982, 23:3115).
EXAMPLE 2C
9-[(2,5-dimethyl-3-thienyl)methyl]guanine
A mixture of 2-amino-9-[(2,5-dimethyl-3-thienyl)methyl]-6-chloropurine (3.8g, 0.0129 mol) and 2N HCl was heated on a steambath for 3.0 hours and then heated under reflux for another hour. At the end of this time 1N NaOH solution was added to the solution till basic and the mixture was heated for another five minutes. The mixture was then acidified with acetic acid,cooled, and filtered to give 3.6 g, of the product. An analytical sample was obtained by chromatography over silica gel using 10% methanol/chloroform as eluting solvent, mp>300° C. (dec).
EXAMPLE 2D
The procedure described in Example 2C was repeated to prepared 9-(3-thenyl)guanine, mp 320°-322° C. (dec).
EXAMPLE 2E
9-(3-furanylmethyl)guanine
The crude 2-amino-9-(3-furfuryl)-6-chloropurine (4.74 g, 0.019 mol) was suspended in methanol (175 ml) and a solution of sodium methoxide, prepared from sodium metal (1.75 g; 0.076 g atom), and methanol (75 ml), was slowly added to the suspension, followed by 2-mercaptoethanol (6.1 ml=6.8 g; 0.087 mol) and water (0.35 ml). The reaction mixture was heated under reflux (N 2 atm) for two hours, when an additional amount of sodium methoxide from 1.14 g sodium (0.05 g atom) and 25 ml methanol was added. After an additional 2.5 hours reflux, the reaction mixture was concentrated under vacuum to 75 ml and then diluted with water (200 ml), and acidified with acetic acid (pH 5.5). The white ppt. was filtered, washed with water, and dried, yield 4.05 g; mp 308°-310° C.
EXAMPLE 3
9-[(5-Ethyl-2-thienyl)methyl]guanine
2-Amino-6-chloro-4-pyrimidinol, monohydrate (22.96 g; 0.1193 mole) was suspended in methoxyethanol (300 ml) and 5-ethyl-2-thenylamine (16.58 g; 0.1193 mole) prepared from 2-ethylthiophene according to the Lit. Procedure, (JACS, 1948, 70:4018) was added to the suspension. The resulting solution was heated under reflux for one hour and then 16.8 ml of triethylamine was added and the refluxing continued for an additional 18 hours. The reaction mixture was poured into ice water (600 ml), dilutedwith acetic acid (100 ml) and then treated with a solution of sodium nitrite (16 g) in water (100 ml). The mixture was stirred at room temperature for 1.5 hours and the resulting salmon colored nitroso compound was collected by filtration and washed with water.
The crude nitrosopyrimidine was then reduced with sodium dithionite in formamide (200 ml) and 90% formic acid (100 ml) at 70° C. and then boiled for 20 minutes. The reaction mixture was diluted with water (300 ml) and the boiling continued for an additional 30 minutes, filtered hot, and then allowed to crystallize in the refrigerator. The crude N-formyl derivative (28 g) was collected by filtration, washed with water and air dried and then cyclized with formic acid (10 ml) and formamide (100 ml) atreflux temperature for four hours. The hot reaction mixture was poured into500 ml of ice water to give the crude guanine which was then purified by dissolving in boiling 1.5 N HCl, treating with charcoal and then precipitating with ammonium hydroxide. The crude guanine was then redissolved in hot 1 N NaOH solution, treated with charcoal, filtered and the filtrate acidified with acetic acid to give the desired product which was used in the next step without further purification.
EXAMPLE 4
The procedure described in Example 3 was repeated to prepare 9-(2-thenyl)guanine, mp>300° C. starting from 2-amino-6-chloro-4-pyrimidinol and 2-thenylamine.
EXAMPLE 5
8-Bromo-9-(2-thienylmethyl)guanine
N-Bromosuccinimide (2.82 g; 15.7 mmol) was added to a cold (0° C.) suspension of 9-(2-thenyl) guanine (3.5 g; 14.1 mmol) in DMF (100 ml) and the mixture was stirred for 30 minutes at 0° C. and then at room temperature for 24 hours. The reaction mixture was then diluted with 75 mlof water and filtered. Recrystallization of the product from DMF gave the analytical sample, yield 3.1 g; mp 294°-295° C. (dec).
EXAMPLE 6
The procedure described in Example 5 was repeated to prepare the following 8-bromo-9-[(substituted heteroaryl)methyl]guanines, starting from appropriate 9-[(substituted heteroaryl)methyl]guanines in each case. 8-bromo-9-(5-ethyl-2-thienylmethyl)guanine 8-bromo-9-(2-furanylmethyl)guanine, mp>340° C. 8-bromo-9-[(2-methyl-3-thienyl)methyl]guanine, mp280° C. (dec). 8-bromo-9-[(benzo[b]thien-3-yl)methyl]guanine, mp 258°-260° C. (dec).
EXAMPLE 7
8-Bromo-9-[(3-pyridinyl)methyl]guanine
N-Bromosuccinimide (1.59 g; 8.95 mmol) was added to a suspension of 9-[(3-pyridyl)methyl]guanine (2.0 g; 8.14 mmol) in glacial acetic acid (20ml) and the mixture was stirred at room temperature for 3.5 hours. The reaction mixture was concentrated under reduced pressure and then diluted with water and filtered. The crude product was triturated with water, filtered, and washed with water and dried. Yield 1.91 g; mp>300° C.
EXAMPLE 8
8-Amino-9-(5-ethyl-2-thienylmethyl)quanine
A mixture of 8-bromo.9-(5-ethyl-2-thenyl)guanine (6.5 g; 18.3 mmol) and 60%aqueous hydrazine (200 ml) was heated to reflux under nitrogen atmosphere for 20 hours. 2-Methoxyethanol (50 ml) was added and the refluxing continued for an additional 48 hours in the open air. The orange-brown solution was cooled, diluted with water (150 ml) and allowed to crystallize in the refrigerator overnight. The crude product thus obtainedwas converted to the hydrochloride salt by recrystallizing from boiling isopropanol and 1 N HCl. Yield, 0.49 g; mp 215°-218° C., dec.
EXAMPLE 9
The procedure described in Example 8 was repeated to prepare the following 8-amino-9-[(substituted heteroaryl)methyl)guanines, starting from appropriate 8-bromo-9-[(substituted heteroaryl)methyl]guanines 8-Amino-9-[(3-pyridyl)methyl]guanine, mp>300° C. and additionally, the following compounds a through e were prepared
a. 8-Amino-9-(2-thenyl)guanine or 8-amino-9-[(2-thienyl)methyl]guanine as hydrochloride salt, 0.5 H 2 O, mp 223°-226° C. (dec).
b. 8-Amino-9-(2-furanylmethyl)guanine monohydrochloride, 1.0 H 2 O, mp 197°-199° C. (dec).
c. 8-Amino-9-[(3-thienyl)methyl]guanine, monohydrochloride, monohydrate, mp275°-278° C. (dec).
d. 8-Amino-9-(3-methyl-2-thienyl)methyl]guanine, 0.25 H 2 O, mp 290° C. (dec).
e. 8-Amino-9-[(benzo[b]thien-3-yl)methyl]guanine, 0.5 H 2 O, mp>300° C. (dec).
Starting materials, such as 2-, 3-, or 4-pyridylmethylamines, 2-thenylaminealso called 2-(aminomethyl)thiophene or 2-thiophene methylamine, and 2-furfurylamine are commercially available (for example, Aldrich Chemical Company). The substituted thenylamines were synthesized from the substituted thiophenes using a general literature procedure. (H. D. Hartough and S. L. Meisel, J. Am. Chem. Soc., 1948, 70:4018).
2-Amino-6-chloro-4-hydroxy-5-nitropyrimidine was synthesized according to amethod described in the literature (A. Stuart and H. C. S. Wood, J. Chem. Soc., 1963:4186).
2-Amino-6-chloro-4-pyrimidinol monohydrate was purchased from Aldrich Chemical Company.
EXAMPLE 10
2-Amino 4[[(2-thienyl)methyl]amino]-5-(formamido)-6-pyrimidinol (a compoundof Scheme 2 Formula IV wherein n is one, m is zero, R 4 and R 5 arehydrogen, Ar is 2-thienyl)
2-Amino-6-chloro-4-pyrimidinol, monohydrate (85%, 100.0 g, 0.5197 mole) wassuspended in methoxyethanol (700 ml) and 2-thiophenemethylamine (96%, 61.3 g, 0.5197 mole) is added to the suspension. The mixture was heated under reflux for two hours and then 73 ml (d=0.726, 0.52 mole) of triethylamine was added and the refluxing continued for an additional 18 hours. (The reaction was followed by TLC: 20% methanol-CHCl 3 .) The reation mixture was poured into ice water (1000 ml), diluted with acetic acid (400ml), and then treated with a solution of sodium nitrite (80 g, 1.16 mole) in water (300 ml). The mixture was stirred at room temperature for four hours, and the resulting reddish colored nitroso compound (X) was collected by filtration and washed with water (the reaction was followed by observing the color change in the formation of the precipitate).
The crude nitrosopyrimidine of Formula X, (of Scheme 2, Formula X, wherein n is one, m is zero, R 4 and R 5 are each hydrogen and Ar is 2-thienyl) prepared above was divided into two batches and each in turn was then reduced with sodium dithionite (>90% 70 g, 0.36 mole) in formamide (300 ml) and 90% formic acid (300 ml) at 80° C. and then boiled for 20 minutes. The temperature was approximately 130°-140° C. at this point. The reaction was complete when the red color completely disappears and inorganic salt precipitates. The reaction mixture was diluted with water (300 ml) and the boiling continuedfor an additional 30 minutes, filtered hot, and then allowed to crystallizein the refrigerator. The reaction was monitored to completion by TLC (SiO 2 ; 20% CH 3 OH in CHCl 3 . The crude N-formyl derivative,2-amino-4[[(2-thienyl)methyl]amino]-5-(formamido)-6-pyrimidinol, (100 g) was collected by filtration, washed with water, and dried and used in the next step without further purification in most cases.
EXAMPLE 10A
The procedure described in Example 10 was repeated to prepare 2-Amino-[[(3-thienyl)methyl]amino]-5-(formamido)-6-pyrimidinol starting from 3-thiophene methylamine and 2-amino-6-chloro-4-pyrimidinol.
EXAMPLE 11
2-Amino-4-[[(2-furanylmethyl)amino]-5-(formamido)-6-pyrimidinol
A mixture of 2-amino-6-chloro-5-nitro-4-pyrimidinol dinol (J CHem. Soc., 1962, p 4186) (31.5 g; 0.15 mol) methanol (1200 ml) and furfurylamine (29.1 g; 0.3 mol) was stirred and heated under reflux (N 2 atm) for six hours. The reaction mixture was cooled, filtered, washed with water, and air dried to give 34.43 g of yellow solid, mp 286°-289° C. (dec), which was used in the next reaction
The crude nitropyrimidine (33.9 g; 0.135 mol) was suspended in formamide (290 ml) and 88% formic acid (145 ml), and then warmed up to 80° C.Sodium dithionite (57 g; 0.327 mol) was slowly added to the warm (80°-85° C.) suspension over a period of 50 minutes, maintained at the temperature (˜85° C.) for another 30 minutes, then diluted with boiling water (1200 ml), and heated the mixturearound 85° C. for another 20 minutes when tan colored crystals were formed. The product was filtered off, washed with water, and dried over P 2 O 5 under vacuum overnight. Yield, 23.4 g, mp 246°-247° C. (dec). In most cases these compounds were carried through the reaction sequences without characterization.
EXAMPLE 11A
The procedure described in Example 11 was repeated to prepare the following2-amino-4[[(heteroaryl or substituted heteroaryl)methyl]amino]-5-(formamido)-6-pyrimidinols, (Table 1) starting from appropriate heteroaryl or substituted heteroaryl methylamines and 2-amino-6-chloro-5-nitro-4-pyrimidinol.
TABLE 1______________________________________ ##STR13##Ar or Ar______________________________________2-Thienyl ##STR14##3-Thienyl ##STR15##3-Furanyl ##STR16##(2-thienyl)methyl ##STR17##3-Me-2-thienyl ##STR18##2-Me-3-thienyl ##STR19##5-Me-2-thienyl ##STR20##2-Pyridinyl ##STR21##Benzo[b]thien-2-yl ##STR22##2-thiazolyl ##STR23##4-thiazolyl ##STR24##(3-thienyl)methyl ##STR25##5-Me-3-thienyl ##STR26##5-Me-2-furanyl ##STR27##4-Me-3-thienyl ##STR28##4-Me-2-thienyl ##STR29##______________________________________
EXAMPLE 12
2,5-Diamino-4-[(2-thienylmethyl)amino]pyrimidin-6-ol, dihydrochloride (a compound of Scheme 2, Formula IVa, wherein n is one, m is zero, R 4 and R 5 are each hydrogen, and Ar is 2-thienyl)
The crude N-formyl derivative as prepared in Example 10 above (40 g, 0.1508mole) was suspended in anhydrous methanol (500 ml) and a stream of dry HCl (g) was passed through the solution while heating the mixture at reflux. The reaction was continued for 2.5 hour when a clear solution was formed followed by a crystalline precipitate. The mixture was cooled in an ice bath and then filtered to give the salt, 2,5-diamino-4-[(2-thienylmethyl)amino]pyrimidin-6-ol, dihydrochloride, (28.6 g). Concentration of the mother liquor gave an additional amount of the salt (8.65 g). Total yield, 37.25 g (79%). The material was carried onwithout further purification.
Alternatively, the N-formyl derivative was refluxed with 5% methanolic-HCl (g) to give the desired diamine. 2 HCl salt.
EXAMPLE 12A
The procedure described in Example 12 was repeated to prepare the following2,5-diamino-4-[[(heteroaryl or substituted heteroaryl)methyl]amino]pyrimidin-6-ol, as dihydrochloride salt (Table 2),starting from appropriate 2-amino-4-[[(heteroaryl or substituted heteroaryl)methyl]amino]-5-(formamido)-6-pyrimidinol (Table 1).
TABLE 2______________________________________ ##STR30##Ar or Ar______________________________________3-Thienyl ##STR31##2-Furanyl ##STR32##3-Furanyl ##STR33##(2-thienyl)methyl ##STR34##3-Me-2-thienyl ##STR35##2-Me-3-thienyl ##STR36##5-Me-2-thienyl ##STR37##2-Pyridinyl ##STR38##Benzo[b]thien-2-yl ##STR39##2-thiazolyl ##STR40##4-thiazolyl ##STR41##(3-thienyl)methyl ##STR42##5-Me-3-thienyl ##STR43##5-Me-2-furanyl ##STR44##4-Me-3-thienyl ##STR45##4-Me-2-thienyl ##STR46##______________________________________
EXAMPLE 13
Methyl [[[2-Amino-1,6-dihydro-6-oxo-4-[(2-thienylmethyl)amino]-5-pyrimidinyl]amino]thioxomethyl]carbamate (A compound of Scheme 2, Formula II wherein R 6 is methyl, n is one, m is zero, R 4 and R 5 - are each hydrogen and Ar is 2-thienyl)
The crude dihydrochloride salt as prepared in Example 12 above (37.2 g, 0.12 mole) was suspended in water (300 ml) and then basified with a mixture of concentrated NH 4 OH and 97% hydrazine (3:1) (40 ml) to give the free base which was dried over vacuum over P 2 O 5 for 20hours. Yield 26.1 g (97%) of the base shown as compound of Scheme II, Formula IVb wherein n, m, R 4 , R 5 , and Ar are as defined above. This free base was unstable.
A suspension of potassium thiocyanate (18.1 g; 0.186 mole) in acetonitrile (250 ml) was treated with methyl chloroformate (99%) (13.8 ml, 0.177 mole)and the mixture was heated at reflux for one hour, cooled, and then filtered to remove inorganic salts. The bright yellow colored filtrate is stirred overnight at room temperature under nitrogen. Care should be takenso that all of the methylchloroformate has reacted before proceeding. The dry base (26.1 g) was added to the solution of methoxycarbonyl isothiocyanate and the stirring continued for 36 hours at room temperatureunder nitrogen. The reaction was monitored to completion by TLC (SiO 2 ; 20% CH 3 OH in CHCl 3 ). The product was filtered off and washed with methanol to give the thiourea derivative, methyl [[[2-amino-1,6-dihydro-6-oxo-4-[(2-thienylmethyl)amino]-5-pyrimidinyl]amino]thioxomethyl]carbamate. Yield 37.4 g (96%), mp 225°-226° C.; (96.6% pure by HPLC).
Alternatively, the nitro or nitrosopyrimidines were catalytically reduced and reacted immediately with ethoxycarbonyl isothiocyanate to give the thiourea derivative.
This material was carried on to the next step without further purification.
EXAMPLE 13A
The procedure described in Example 13 was repeated to prepare the followingmethyl (or ethyl) [[[2-amino-1,6-dihydro-6-oxo-4-[[(heteroaryl or substituted heteroaryl)methyl]amino]-5-pyrimidinyl]amino]thioxomethyl]carbamate (Table3) starting from appropriate 2,5-diamino-4-[[(heteroaryl or substituted heteroaryl)methyl]amino]pyrimidin-6-ol, dihydrochloride salt (Table 2).
TABLE 3______________________________________ ##STR47##Ar or Ar R.sub.6______________________________________2-Thienyl ##STR48## Et3-Thienyl ##STR49## CH.sub.32-Furanyl ##STR50## CH.sub.33-Furanyl ##STR51## CH.sub.3 mp 246-249° C. (dec)(2-thienyl)methyl ##STR52## CH.sub.3 mp 234-239° C. (dec)2-Me-3-thienyl ##STR53## CH.sub.3 mp 235-237° C. (dec)5-Me-2-thienyl ##STR54## CH.sub.3, mp 227-230° C. (dec)2-Me-2-thienyl " Et2-Pyridinyl ##STR55## CH.sub.3Benzo[b]thien-2-yl ##STR56## CH.sub.32-thiazolyl ##STR57## CH.sub.3 mp 214-215° C.4-thiazolyl ##STR58## CH.sub.3 mp 217-218° C.(3-thienyl)methyl ##STR59## CH.sub.35-Me-3-thienyl ##STR60## CH.sub.35-Me-2-furanyl ##STR61## CH.sub.3 mp 228-229° C. (dec)4-Me-3-thienyl ##STR62## CH.sub.3, Et4-Me-2-thienyl ##STR63## CH.sub.3, Et______________________________________
EXAMPLE 14
Methyl [5-amino-7-[(2-thienylmethyl)amino]oxazolo[5,4-d]pyrimidin-2-yl]carbamate (See Scheme 2, Formula III wherein R 6 is methyl, n is one, m is zero,R 4 and R 5 are each hydrogen and Ar is 2-thienyl)
A mixture of the thiourea derivative as prepared in Example 13 (35 g; 0.096mole) and N,N'-dicyclohexylcarbodiimide (DCC) (59.4 g, 0.288 mole) was suspended in dry DMF (1800 ml) and stirred at room temperature for 24 hours. The course of the reaction was followed by TLC (SiO 2 ; 20%, CH 3 OH in CHCL 3 ). The DMF was completely stripped of under vacuum and the residue triturated twice with CH 2 Cl 2 to give thedesired carbamate, methyl [5-amino-7-[(2-thienylmethyl)amino]oxazolo[5,4-d]pyrimidin-2-yl]carbamate.Yield 27.8 g (90%), mp 300° C. Purity 97.6% (HPLC).
This material was carried on to the next step without further purification.
EXAMPLE 14A
The procedure described in Example 14 was repeated to prepare the followingmethyl (or ethyl) [5-amino-7-[[(heteroaryl or substituted heteroaryl)methyl]amino]oxazolo[5,4-d]pyrimidin-2-yl]carbamate (Table 4) starting from appropriate methyl (or ethyl) [[[2-amino-1,6-dihydro-6-oxo-4-[[(heteroaryl or substituted heteroaryl)methyl]amino]-5-pyrimidinyl]amino]thioxomethyl]carbamate (Table3).
TABLE 4______________________________________ ##STR64##Ar or Ar R.sub.6______________________________________2-Thienyl ##STR65## Et3-Thienyl ##STR66## CH.sub.32-Furanyl ##STR67## CH.sub.33-Furanyl ##STR68## CH.sub.3 mp 288-291° C. (dec)(2-thienyl)methyl ##STR69## CH.sub.3 mp >270° C. (dec)2-Me-3-thienyl ##STR70## CH.sub.3 mp >270° C. (dec)5-Me-2-thienyl ##STR71## CH.sub.3, Et p >250° C. (dec)2-Pyridinyl ##STR72## CH.sub.3Benzo[b]thien-2-yl ##STR73## CH.sub.32-thiazolyl ##STR74## CH.sub.34-thiazolyl ##STR75## CH.sub.3(3-thienyl)methyl ##STR76## CH.sub.35-Me-3-thienyl ##STR77## CH.sub.35-Me-2-furanyl ##STR78## CH.sub.35-Me-2-thienyl ##STR79## CH.sub.3, Et5-Me-3-thienyl ##STR80## CH.sub.34-Me-2-thienyl ##STR81## Et mp >260° C. (dec)______________________________________
EXAMPLE 15
Methyl [2-amino-6,9-dihydro-6-oxo-9-(2-thienylmethyl-1H-purin-8-yl]carbamate (SeeScheme 2, Formula I wherein R 3 is NHCOOR 6 Wherein R 6 is methyl, n is one, m is zero, R 4 and R 5 are each hydrogen and Ar is 2-thienyl)
A mixture of the oxazolocarbamate as prepared in Example 14 (25 g; 0.078 mole) and anhydrous K 2 CO 3 was suspended in anhydrous methanol and heated to reflux for eight hours. The course of the reaction is being followed by the TLC system mentioned above. The reaction mixture was then evaporated to dryness under reduced pressure and the residue dissolved in ammonium chloride solution (16.8 g; 0.312 mole in 200 ml of water). The resulting precipitate was collected and dried giving 24.39 g of the methyl[2-amino -6,9-dihydro-6-oxo-9-(2-thienylmethyl)-1H-pyrin-8-yl]carbamate, sometimes contaminated with the 8-amino compound, i.e., in this example, 89.58% carbamate and 9.54% 8-amino compound, 8-amino-9[(2-thienyl)methyl]guanine of Formula I wherein R 3 is NH 2 .
This material was carried on to the next step without further purification.
EXAMPLE 15A
The procedure described in Example 15 was repeated to prepare the followingmethyl (or ethyl) [2-amino-6,9-dihydro-6-oxo-9-[(heteroaryl or substituted heteroaryl)methyl-1H-purin-8-yl]carbamate (Table 5) starting from appropriate methyl (or ethyl) [5-amino-7-[[(heteroaryl or substituted heteroaryl)methyl]amino]oxazolo[5,4-d]pyrimidin-2-yl]carbamate (Table 4).
TABLE 5______________________________________ ##STR82##Ar or Ar R.sub.6______________________________________2-Thienyl ##STR83## Et, mp >250° C. (dec)3-Thienyl ##STR84## CH.sub.32-Furanyl ##STR85## CH.sub.3 mp >300° C. (dec)3-Furanyl ##STR86## CH.sub.3 mp >270° C. (dec)(2-thienyl)methyl ##STR87## CH.sub.32-Me-3-thienyl ##STR88## CH.sub.35-Me-2-thienyl ##STR89## CH.sub. 3, Et mp >250° C. (dec)2-Pyridinyl ##STR90## CH.sub.3Benzo[b]thien-2-yl ##STR91## CH.sub.32-thiazolyl ##STR92## CH.sub.34-thiazolyl ##STR93## CH.sub.3(3-thienyl)methyl ##STR94## CH.sub.35-Me-3-thienyl ##STR95## CH.sub.35-Me-2-furanyl ##STR96## CH.sub.3 mp >250° C. (dec)4-Me-3-thienyl ##STR97## CH.sub.3, Et4-Me-2-thienyl ##STR98## CH.sub.3, Et______________________________________
EXAMPLE 16
8-Amino-9-[(2-thienyl)methyl]guanine (See Scheme 2 Formula I Wherein R 3 is NH 2 , n is one, m is zero, R 4 and R 5 are each hydrogen and Ar is 2-thienyl)
The crude carbamate as prepared in Example 15 (89.5% the carbamate plus 9.5% the 8-amino compound (20.39 g; 0.064 mole) from the previous reactionis suspended in isopropanol (125 ml) and 1N HCl (125 ml; 0.125 mole) and the mixture heated at reflux for ˜20 hours (the reaction is monitored by TLC (SiO 2 :20% MeOH in CHCl 3 ; CH 3 CN:HOAc:H 2 O 8:1:1)), when a clear solution is formed. On cooling theproduct crystallizes out from the solution as the hydrochloride salt of 8-amino-9[(2-thienyl)methyl]guanine. Yield 15.1 g (76%). Purity 98% by HPLC, mp 219°-222° C. (dec).
The hydrolysis was also carried out in 10% methanolic sodium hydroxide solution under reflux temperature, followed by neutralization and recrystallization from appropriate solvent.
EXAMPLE 16A
The procedure described in Example 16 was repeated to prepare the following8-amino-9](heteroaryl or substituted heteroaryl)methyl]guanines (Table 6) starting from appropriate methyl (or ethyl) [2-amino-6,9-dihydro-6-oxo-9-[(heteroaryl or substituted heteroaryl)methyl-1H-purin-8-yl]carbamate (Table 5).
TABLE 6______________________________________ ##STR99##Ar or Ar X mp ° C.______________________________________2-Furanyl ##STR100## HCl 253-7a. 3-Thienyl ##STR101## HCl.H.sub.2 O 275-8 (d)b. 3-Furanyl ##STR102## HCl 293-4 (d)c. (2-thienyl)methyl ##STR103## HCl.H.sub.2 O 153-5 (d)d. 2-Me-3-thienyl ##STR104## HCl 266-8 (d)e. 5-Me-2-thienyl ##STR105## HCl.0.25 H.sub.2 O >260f. 2-Pyridinyl ##STR106## 1.5 HCl. 0.25 H.sub.2 O 270-2 (d)g. Benzo[b]thien-2-yl ##STR107## 0.25 H.sub.2 O >300 (d)h. 2-thiazolyl ##STR108## 1.2 HCl 1.2 H.sub.2 O >250i. 4-thiazolyl ##STR109## 1.1 HCl 0.3 H.sub.2 O >250j. (3-thienyl)methyl ##STR110## 0.9 HCl. H.sub.2 O 177-83 (d)k. 5-Me-3-thienyl ##STR111## HCl.0.5 H.sub.2 O 212-5 (d)l. 5-Me-2-furanyl ##STR112## HCl.1.15 H.sub.2 O 212-4 (d)m. 4-Me-3-thienyl ##STR113## 0.9 HCl 1.25 H.sub.2 O >240 (d)n. 4-Me-2-thienyl ##STR114##______________________________________
EXAMPLE 17
2,8-Diamino-1,9-dihydro-9-(2-thienylmethyl-6H-purine-6-thione
A mixture of P 2 S 5 (2.4 g; 10.95 mmol), pyridine (30 ml) and 8-amino-9[(2-thienyl)methyl]guanine (1.5 g; 4.87 mmol) was heated under reflux for 4.5 hours and then poured into 200 ml of boiling water and boiled for one hour. The mixture was allowed to stand at room temperature overnight. The precipitated solid was collected, dissolved in 1N NaOH, treated with activated charcoal, filtered, and then acidified with glacialacetic acid to pH 5.4. The precipitated solid was collected, dissolved in 1N HCl, treated with activated charcoal, filtered, and neutralized with NH 4 OH to pH 7.07 to give 542 mg of the desired product, mp>300° C.
EXAMPLE 17A
The procedure described in Example 17 was repeated to prepare the following2,8-diamino-1,9-dihydro-9-[(heteroaryl or substituted heteroaryl)methyl]-6H-purin-6-thione, starting from appropriate 8-amino-9[(heteroaryl or substituted heteroaryl)alkyl]guanine.
2,8-Diamino-1,9-dihydro-9-(3-thienylmethyl)-6H-purine-6-thione, 0.5 H 2 O, mp 275° C. (dec).
2,8-Diamino-1,9-dihydro-9-[2-(2-thienyl)ethyl]6H-purine-6-thione, 0.25 H 2 O, mp>260° C. (dec).
EXAMPLE 18
2-Amino-7,9-dihydro-9-(2-thienylmethyl)-1H-purine-6,8-dione
A mixture of 8-bromo-9-[(2-thienyl)methyl]guanine (see Example 5) (3.12 g; 9.56 mmol), acetic anhydride (75 ml), glacial acetic acid (75 ml) and anhydrous sodium acetate (14.9 g; 0.1816 mol) was heated to reflux for 20 hours. The dark solution which formed was then evaporated to dryness underreduced pressure. The residue was dissolved in aqueous methylamine (150 ml), stirred at room temperature for 48 hours and then heated to reflux for 2.5 hours. The methylamine was distilled off under reduced pressure and the residue was recrystallized from boiling methanol-water mixture to give 1.23 g of the analytical product, mp>300° C.
EXAMPLE 19
2-Amino-1,7,8,9-tetrahydro-9-(2-thienylmethyl)-8-thioxo-6H-purin-6-one
A mixture of 8-bromo-9-[(2-thienyl)methyl]guanine (see Example 5) (2.0 g; 6.13 mmol), DMF (250 ml), and thiourea (0.93 g; 12.26 mmol) was heated under reflux for 20 hours and then the solvent was evaporated to dryness under reduced pressure. The residue was dissolved in 1N NaOH, treated withcharcoal, filtered, and acidified with glacial AcOH to give a pale yellow solid. Analytical sample was prepared by repeating the purification process, yield 709 mg; mp>280° C.
EXAMPLE 20
N,N'-[6,9-dihydro-6-oxo-9-(2-thienylmethyl)-1H-purin-2,8-di-yl]bis acetamide
A mixture of 8-amino-9-[(2-thienyl)methyl]guanine (0.5 g; 1.88 mmol), DMF (10 ml), pyridine (5 ml), and acetic anhydride (5 ml) was stirred at room temperature for 36 hours. The mixture was diluted with ether (50 ml) and filtered to give analytically pure product, mp 243°-4° C.
STARTING MATERIALS
Starting materials are prepared as follows using a known procedure or following a procedure analogous to that known in the art.
5-Methyl-2-thienylmethylamine, H. Hartough, et al, J. Am. Chem. Soc., 1948,70:4018.
Benzo[b]thiophen-2-yl-methylamine, D. Shirley, et al, J. Am. Chem. Soc., 1952, 74:664.
3-Methyl-2-thienylmethylamine, H. Hartough, et al, J. Am. Chem. Soc., 1948,70:4018.
Benzo[b]thiophen-3-yl-methylamine was prepared by Gabriel Synthesis from the corresponding chlorocompound (W. King, et al, J. Org. Chem., 1948, 13:635).
2-Methyl-3-thienylmethylamine was prepared by lithium aluminum hydride (LAH) reduction of the corresponding nitrile (M. Janda, et al, Coll. Czech. Comm., 1974, 39:959).
2-(2-thienyl)ethylamine and 2-(3-thienyl)ethylamine were prepared by the lit. method of W. Hertz, et al, in J. Am. Chem. Soc., 1951, 73:351.
2-Methyl-4-thienyl methylamine was prepared by LAH reduction of 2-methyl-4-cyano-thiophene which was prepared from the corresponding 4-bromo compound (Y. Goldfarb, et al, Zh. Obs. Khim. 1964, 34:969) and CuCN.
3-Methyl-4-thienylmethylamine was similarly prepared as follows: ##STR115##
4-Methyl-2-thienylmethylamine was prepared by LAH reduction of the corresponding aldoxime.
2- and 4- Thiazolylmethyl amines were prepared according to the literature procedures (R. G. Jones, et al, J. Am. Chem. Soc., 1950, 72:4526). | Novel purine derivatives, particularly novel guanines and hypoxanthines, are described as agents for treating autoimmune diseases. Also novel methods of manufacture for the derivatives, pharmaceutical compositions thereof, and methods of use therefor are the invention. | 2 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a divisional of co-pending application Ser. No. 10/678,562 which is a continuation-in-part of co-pending application Ser. No. 10/259,139, filed on Sep. 27, 2002, which is a continuation-in-part of co-pending application Ser. No. 10/123,389, filed on Apr. 16, 2002, all of which are incorporated herein by reference.
FIELD OF THE INVENTION
[0002] This invention relates to novel arylindenopyridines and arylindenopyrimidines and their therapeutic and prophylactic uses. Disorders treated and/or prevented using these compounds include neurodegenerative and movement disorders ameliorated by antagonizing Adenosine A2 a receptors.
BACKGROUND OF THE INVENTION
Adenosine A2a Receptors
[0003] Adenosine is a purine nucleotide produced by all metabolically active cells within the body. Adenosine exerts its effects via four subtypes of cell-surface receptors (A1, A2a , A2 b and A3), which belong to the G protein coupled receptor superfamily (Stiles, G. L. Journal of Biological Chemistry, 1992, 267, 6451). A1 and A3 couple to inhibitory G protein, while A2a and A2 b couple to stimulatory G protein. A2a receptors are mainly found in the brain, both in neurons and glial cells (highest level in the striatum and nucleus accumbens, moderate to high level in olfactory tubercle, hypothalamus, and hippocampus etc. regions) (Rosin, D. L.; Robeva, A.; Woodard, R. L.; Guyenet, P. G.; Linden, J. Journal of Comparative Neurology ,1998, 401, 163).
[0004] In peripheral tissues, A2a receptors are found in platelets, neutrophils, vascular smooth muscle and endothelium (Gessi, S.; Varani, K.; Merighi, S.; Ongini, E.; Borea, P. A. British Journal of Pharmacology, 2000, 129, 2). The striatum is the main brain region for the regulation of motor activity, particularly through its innervation from dopaminergic neurons originating in the substantia nigra. The striatum is the major target of the dopaminergic neuron degeneration in patients with Parkinson's Disease (PD). Within the striatum, A2 a receptors are co-localized with dopamine D2 receptors, suggesting an important site for the integration of adenosine and dopamine signaling in the brain (Fink, J. S.; Weaver, D. R.; Rivkees, S. A.; Peterfreund, R. A.; Pollack, A. E.; Adler, E. M.; Reppert, S. M. Brain Research Molecular Brain Research, 1992, 14, 186).
[0005] Neurochemical studies have shown that activation of A2 a receptors reduces the binding affinity of D2 agonist to their receptors. This D2R and A2aR receptor-receptor interaction has been demonstrated in striatal membrane preparations of rats (Ferre, S.; von Euler, G.; Johansson, B.; Fredholm, B. B.; Fuxe, K. Proceedings of the National Academy of Sciences of the United States of America, 1991, 88, 7238) as well as in fibroblast cell lines after transfected with A2a R and D2 R cDNAs (Salim, H.; Ferre, S.; Dalal, A.; Peterfreund, R. A.; Fuxe, K.; Vincent, J. D.; Lledo, P. M. Journal of Neurochemistry, 2000, 74, 432). In vivo, pharmacological blockade of A2a receptors using A2a antagonist leads to beneficial effects in dopaminergic neurotoxin MPTP(1-methyl-4-pheny-1,2,3,6-tetrahydropyridine)-induced PD in various species, including mice, rats, and monkeys (Ikeda, K.; Kurokawa, M.; Aoyama, S.; Kuwana, Y. Journal of Neurochemistry, 2002, 80, 262). Furthermore, A2a knockout mice with genetic blockade of A2a function have been found to be less sensitive to motor impairment and neurochemical changes when they were exposed to neurotoxin MPTP (Chen, J. F.; Xu, K.; Petzer, J. P.; Staal, R.; Xu, Y. H.; Beilstein, M.; Sonsalla, P. K.; Castagnoli, K.; Castagnoli, N., Jr.; Schwarzschild, M. A. Journal of Neuroscience, 2001, 21, RC143).
[0006] In humans, the adenosine receptor antagonist theophylline has been found to produce beneficial effects in PD patients (Mally, J.; Stone, T. W. Journal of the Neurological Sciences, 1995, 132, 129). Consistently, recent epidemiological study has shown that high caffeine consumption makes people less likely to develop PD (Ascherio, A.; Zhang, S. M.; Heman, M. A.; Kawachi, I.; Colditz, G. A.; Speizer, F. E.; Willett, W. C. Annals of Neurology, 2001, 50, 56). In summary, adenosine A2a receptor blockers may provide a new class of antiparkinsonian agents (Impagnatiello, F.; Bastia, E.; Ongini, E.; Monopoli, A. Emerging Therapeutic Targets, 2000, 4, 635).
SUMMARY OF THE INVENTION
[0007] This invention provides a compound having the structure of Formula I or II
[0008] or a pharmaceutically acceptable salt thereof, wherein
[0009] (a) R 1 is selected from the group consisting of
(i) —COR 5 , wherein R 5 is selected from H, optionally substituted C 1-8 straight or branched chain alkyl, optionally substituted aryl and optionally substituted arylalkyl; wherein the substituents on the alkyl, aryl and arylalkyl group are selected from C 1-8 alkoxy, phenylacetyloxy, hydroxy, halogen, p-tosyloxy, mesyloxy, amino, cyano, carboalkoxy, or NR 7 R 8 wherein R 7 and R 8 are independently selected from the group consisting of hydrogen, C 1-8 straight or branched chain alkyl, C 3-7 cycloalkyl, benzyl, aryl, or heteroaryl or NR 7 R 8 taken together form a heterocycle or heteroaryl; (ii) COOR 5 , wherein R 5 is as defined above; (ii) cyano; (iii) —CONR 9 R 10 wherein R 9 and R 10 are independently selected from H, C 1-8 straight or branched chain alkyl, C 3-7 cycloalkyl, trifluoromethyl, hydroxy, alkoxy, acyl, alkylcarbonyl, carboxyl, arylalkyl, aryl, heteroaryl and heterocyclyl; wherein the alkyl, cycloalkyl, alkoxy, acyl, alkylcarbonyl, carboxyl, arylalkyl, aryl, heteroaryl and heterocyclyl groups may be substituted with carboxyl, alkyl, aryl, substituted aryl, heterocyclyl, substituted heterocyclyl, heteroaryl, substituted heteroaryl, hydroxamic acid, sulfonamide, sulfonyl, hydroxy, thiol, amino, alkoxy or arylalkyl, or R 9 and R 10 taken together with the nitrogen to which they are attached form a heterocycle or heteroaryl group; (v) optionally substituted C 1-8 straight or branched chain alkyl; wherein the substituents on the alkyl, group are selected from C 1-8 alkoxy, phenylacetyloxy, hydroxy, halogen, p-tosyloxy, mesyloxy, amino, cyano, carboalkoxy, carboxyl, aryl, heterocyclyl, heteroaryl, sulfonyl, thiol, alkylthio, or NR 7 R 8 wherein R 7 and R 8 are as defined above;
[0018] (b) R 2 is selected from the group consisting of optionally substituted alkyl, optionally substituted aryl, optionally substituted heteroaryl, optionally substituted heterocyclyl and optionally substituted C 3-7 cycloalkyl, C 1-8 alkoxy, aryloxy, C 1-8 alkylsulfonyl, arylsulfonyl, arylthio, C 1-8 alkylthio, or —NR 24 R 25
wherein R 24 and R 25 are independently selected from H, C 1-8 straight or branched chain alkyl, arylalkyl, C 3-7 cycloalkyl, carboxyalkyl, aryl, heteroaryl, and heterocyclyl or R 24 and R 25 taken together with the nitrogen form a heteroaryl or heterocyclyl group,
[0020] (c) R 3 is from one to four groups independently selected from the group consisting of: hydrogen, halo, C 1-8 straight or branched chain alkyl, arylalkyl, C 3-7 cycloalkyl, C 1-8 alkoxy, cyano, C 1-4 carboalkoxy, trifluoromethyl, C 1-8 alkylsulfonyl, halogen, nitro, hydroxy, trifluoromethoxy, C 1-8 carboxylate, aryl, heteroaryl, and heterocyclyl, —NR 11 R 12 ,
wherein R 11 , and R 12 are independently selected from H, C 1-8 straight or branched chain alkyl, arylalkyl, C 3-7 cycloalkyl, carboxyalkyl, aryl, heteroaryl, and heterocyclyl or R 10 and R 11 taken together with the nitrogen form a heteroaryl or heterocyclyl group,
[0022] —NR 13 COR 14 ,
wherein R 13 is selected from hydrogen or alkyl and R 14 is selected from hydrogen, alkyl, substituted alkyl, C 1-3 alkoxyl, carboxyalkyl, aryl, arylalkyl, heteroaryl, heterocyclyl, R 15 R 16 N(CH 2 ) p —, or R 15 R 16 NCO(CH 2 ) p —, wherein R 15 and R 16 are independently selected from H, OH, alkyl, and alkoxy, and p is an integer from 1-6, wherein the alkyl group may be substituted with carboxyl, alkyl, aryl, substituted aryl, heterocyclyl, substituted heterocyclyl, heteroaryl, substituted heteroaryl, hydroxamic acid, sulfonamide, sulfonyl, hydroxy, thiol, alkoxy or arylalkyl, or R 13 and R 14 taken together with the carbonyl form a carbonyl containing heterocyclyl group;
[0024] (d) R 4 is selected from the group consisting of hydrogen, C 1-6 straight or branched chain alkyl, benzyl
wherein the alkyl and benzyl groups are optionally substituted with one or more groups selected from C 3-7 cycloalkyl, C 1-8 alkoxy, cyano, C 1-4 carboalkoxy, trifluoromethyl, C 1-8 alkylsulfonyl, halogen, nitro, hydroxy, trifluoromethoxy, C 1-8 carboxylate, amino, NR 17 R 18 , aryl and heteroaryl,
[0026] —OR 17 , and —NR 17 R 18 ,
wherein R 17 and R 18 are independently selected from hydrogen, and optionally substituted C 1-6 alkyl or aryl; and
[0028] (e) X is selected from C═S, C═O; CH 2 , CHOH, CHOR 19 ; or CHNR 20 R 21 where R 19 , R 20 , and R 21 , are selected from optionally substituted C 1-8 straight of branched chain alkyl, wherein the substituents on the alkyl group are selected from C 1-8 alkoxy, hydroxy, halogen, amino, cyano, or NR 22 R 23 wherein R 22 and R 23 are independently selected from the group consisting of hydrogen, C 1-8 straight or branched chain alkyl, C 3-7 cycloalkyl, benzyl, aryl, heteroaryl, or NR 22 R 23 taken together from a heterocycle or heteroaryl;
[0029] with the proviso that in a compound of Formula II when R 1 is a cyano, then R 2 is not phenyl.
[0030] This invention also provides a pharmaceutical composition comprising the instant compound and a pharmaceutically acceptable carrier.
[0031] This invention further provides a method of treating a subject having a condition ameliorated by antagonizing Adenosine A2a receptors, which comprises administering to the subject a therapeutically effective dose of the instant pharmaceutical composition.
[0032] This invention further provides a method of preventing a disorder ameliorated by antagonizing Adenosine A2a receptors in a subject, comprising of administering to the subject a prophylactically effective dose of the compound of claim 1 either preceding or subsequent to an event anticipated to cause a disorder ameliorated by antagonizing Adenosine A2a receptors in the subject.
DETAILED DESCRIPTION OF THE INVENTION
[0033] Compounds of Formula I are potent small molecule antagonists of the Adenosine A2a receptors that have demonstrated potency for the antagonism of Adenosine A2a, A1, and A3 receptors.
[0034] Preferred embodiments for R 1 are COOR 5 wherein R 5 is an optionally substituted C 1-8 straight or branched chain alkyl. Preferably the alkyl chain is substituted with a dialkylamino group.
[0035] Preferred embodiments for R 2 are optionally substituted heteroaryl and optionally substituted aryl. Preferably, R 2 is an optionally substituted furan.
[0036] Preferred substituents for R 3 include hydrogen, halo, hydroxy, amino, trifluoromethyl, alkoxy, hydroxyalkyl chains, and aminoalkyl chains,
[0037] Preferred substituents for R 4 include NH 2 and alkylamino.
[0038] In a preferred embodiment, the compound is selected from the group of compounds shown in Tables 1 and 2 hereinafter.
[0039] More preferably, the compound is selected from the following compounds:
[0040] The compound of claim 1 , formula I, wherein R 4 is amino.
2-amino-4-furan-2-yl-indeno[1,2-d]pyrimidin-5-one
[0041]
2-amino-4-phenyl-indeno[1,2-d]pyrimidin-5-one
[0042]
2-amino-4-thiophen-2-yl-indeno[1,2-d]pyrimidin-5-one
[0043]
2-amino-4-(5-methyl-furan-2-yl)-indeno[1,2-d]pyrimidin-5-one
[0044]
2,6-diamino-4-furan-2-yl-indeno[1,2-d]pyrimidin-5-one
[0045]
9H-indeno[2,1-c]pyridine-4-carbonitrile,3-amino-1-furan-2-yl-9-oxo-
[0046]
9H-indeno[2,1-c]pyridine-4-carboxylic acid,3-amino-1-furan-2-yl-9-oxo-,2-dimethylamino-ethyl ester
[0047]
9H-indeno[2,1-c]pyridine-4-carboxylic acid,3-amino-1-phenyl-9-oxo-,2-dimethylamino-ethyl ester
[0048]
9H-indeno[2,1-c]pyridine-4-carboxylic acid,3-amino1-furan-2-yl-9-oxo-,(2-dimethylamino-1-methyl-ethyl)-amide
[0049]
9H-indeno[2,1-c]pyridine-4-carboxylic acid,3-amino-1 -furan-2-yl-9-oxo-,(2-dimethylamino-ethyl)-methyl-amide
[0050]
9H-indeno[2,1-c]pyridine-4-carboxylic acid,3-amino-1-furan-2-yl-9-oxo-,1-methyl-pyrrolidin-2-ylmethyl ester
[0051] The instant compounds can be isolated and used as free bases. They can also be isolated and used as pharmaceutically acceptable salts. Examples of such salts include hydrobromic, hydroiodic, hydrochloric, perchloric, sulfuric, maleic, fumaric, malic, tartaric, citric, benzoic, mandelic, methanesulfonic, hydroethanesulfonic, benzenesulfonic, oxalic, palmoic, 2-naphthalenesulfonic, p-toluenesulfonic, cyclohexanesulfamic and saccharic.
[0052] This invention also provides a pharmaceutical composition comprising the instant compound and a pharmaceutically acceptable carrier.
[0053] Pharmaceutically acceptable carriers are well known to those skilled in the art and include, but are not limited to, from about 0.01 to about 0.1 M and preferably 0.05 M phosphate buffer or 0.8% saline. Such pharmaceutically acceptable carriers can be aqueous or non-aqueous solutions, suspensions and emulsions. Examples of non-aqueous solvents are propylene glycol, polyethylene glycol, vegetable oils such as olive oil, and injectable organic esters such as ethyl oleate. Aqueous carriers include water, ethanol, alcoholic/aqueous solutions, glycerol, emulsions or suspensions, including saline and buffered media. Oral carriers can be elixirs, syrups, capsules, tablets and the like. The typical solid carrier is an inert substance such as lactose, starch, glucose, methyl-cellulose, magnesium stearate, dicalcium phosphate, mannitol and the like. Parenteral carriers include sodium chloride solution, Ringer's dextrose, dextrose and sodium chloride, lactated Ringer's and fixed oils. Intravenous carriers include fluid and nutrient replenishers, electrolyte replenishers such as those based on Ringer's dextrose and the like. Preservatives and other additives can also be present, such as, for example, antimicrobials, antioxidants, chelating agents, inert gases and the like. All carriers can be mixed as needed with disintegrants, diluents, granulating agents, lubricants, binders and the like using conventional techniques known in the art.
[0054] This invention further provides a method of treating a subject having a condition ameliorated by antagonizing Adenosine A2a receptors, which comprises administering to the subject a therapeutically effective dose of the instant pharmaceutical composition.
[0055] In one embodiment, the disorder is a neurodegenerative or movement disorder. Examples of disorders treatable by the instant pharmaceutical composition include, without limitation, Parkinson's Disease, Huntington's Disease, Multiple System Atrophy, Corticobasal Degeneration, Alzheimer's Disease, and Senile Dementia.
[0056] In one preferred embodiment, the disorder is Parkinson's disease.
[0057] As used herein, the term “subject” includes, without limitation, any animal or artificially modified animal having a disorder ameliorated by antagonizing adenosine A2a receptors. In a preferred embodiment, the subject is a human.
[0058] Administering the instant pharmaceutical composition can be effected or performed using any of the various methods known to those skilled in the art. The instant compounds can be administered, for example, intravenously, intramuscularly, orally and subcutaneously. In the preferred embodiment, the instant pharmaceutical composition is administered orally. Additionally, administration can comprise giving the subject a plurality of dosages over a suitable period of time. Such administration regimens can be determined according to routine methods.
[0059] As used herein, a “therapeutically effective dose” of a pharmaceutical composition is an amount sufficient to stop, reverse or reduce the progression of a disorder. A “prophylactically effective dose” of a pharmaceutical composition is an amount sufficient to prevent a disorder, i.e., eliminate, ameliorate and/or delay the disorder's onset. Methods are known in the art for determining therapeutically and prophylactically effective doses for the instant pharmaceutical composition. The effective dose for administering the pharmaceutical composition to a human, for example, can be determined mathematically from the results of animal studies.
[0060] In one embodiment, the therapeutically and/or prophylactically effective dose is a dose sufficient to deliver from about 0.001 mg/kg of body weight to about 200 mg/kg of body weight of the instant pharmaceutical composition. In another embodiment, the therapeutically and/or prophylactically effective dose is a dose sufficient to deliver from about 0.05 mg/kg of body weight to about 50 mg/kg of body weight. More specifically, in one embodiment, oral doses range from about 0.05 mg/kg to about 100 mg/kg daily. In another embodiment, oral doses range from about 0.05 mg/kg to about 50 mg/kg daily, and in a further embodiment, from about 0.05 mg/kg to about 20 mg/kg daily. In yet another embodiment, infusion doses range from about 1.0 μg/kg/min to about 10 mg/kg/min of inhibitor, admixed with a pharmaceutical carrier over a period ranging from about several minutes to about several days. In a further embodiment, for topical administration, the instant compound can be combined with a pharmaceutical carrier at a drug/carrier ratio of from about 0.001 to about 0.1.
Definitions and Nomenclature
[0061] Unless otherwise noted, under standard nomenclature used throughout this disclosure the terminal portion of the designated side chain is described first, followed by the adjacent functionality toward the point of attachment.
[0062] As used herein, the following chemical terms shall have the meanings as set forth in the following paragraphs: “independently”, when in reference to chemical substituents, shall mean that when more than one substituent exists, the substituents may be the same or different.
[0063] “Alkyl” shall mean straight, cyclic and branched-chain alkyl. Unless otherwise stated, the alkyl group will contain 1-20 carbon atoms. Unless otherwise stated, the alkyl group may be optionally substituted with one or more groups such as halogen, OH, CN, mercapto, nitro, amino, C 1—C 8 -alkyl, C 1 -C 8 -alkoxyl, C 1 -C 8 -alkylthio, C 1 -C 8 -alkyl-amino, di(C 1 -C 8 -alkyl)amino, (mono-, di-, tri-, and per-) halo-alkyl, formyl, carboxy, alkoxycarbonyl, C 1 -C 8 -alkyl-CO—O—, C 1 —C 8 -alkyl-CO—NH—, carboxamide, hydroxamic acid, sulfonamide, sulfonyl, thiol, aryl, aryl(c 1 —C 8 )alkyl, heterocyclyl, and heteroaryl. “Alkoxy” shall mean —O-alkyl and unless otherwise stated, it will have 1-8 carbon atoms.
[0064] The term “bioisostere” is defined as “groups or molecules which have chemical and physical properties producing broadly similar biological properties.” (Burger's Medicinal Chemistry and Drug Discovery, M. E. Wolff, ed. Fifth Edition, Vol. 1, 1995, Pg. 785).
[0065] “Halogen” shall mean fluorine, chlorine, bromine or iodine; “PH” or “Ph” shall mean phenyl; “Ac” shall mean acyl; “Bn” shall mean benzyl.
[0066] The term “acyl” as used herein, whether used alone or as part of a substituent group, means an organic radical having 2 to 6 carbon atoms (branched or straight chain) derived from an organic acid by removal of the hydroxyl group. The term “Ac” as used herein, whether used alone or as part of a substituent group, means acetyl.
[0067] “Aryl” or “Ar,” whether used alone or as part of a substituent group, is a carbocyclic aromatic radical including, but not limited to, phenyl, 1- or 2-naphthyl and the like. The carbocyclic aromatic radical may be substituted by independent replacement of 1 to 5 of the hydrogen atoms thereon with halogen, OH, CN, mercapto, nitro, amino, C 1 -C 8 -alkyl, C 1 -C 8 -alkoxyl, C 1 -C 8 -alkylthio, C 1 -C 8 -alkyl-amino, di(C 1 -C 8 -alkyl)amino, (mono-, di-, tri-, and per-) halo-alkyl, formyl, carboxy, alkoxycarbonyl, C 1 -C 8 -alkyl-CO—O—, C 1 -C 8 -alkyl-CO—NH—, or carboxamide. Illustrative aryl radicals include, for example, phenyl, naphthyl, biphenyl, fluorophenyl, difluorophenyl, benzyl, benzoyloxyphenyl, carboethoxyphenyl, acetylphenyl, ethoxyphenyl, phenoxyphenyl, hydroxyphenyl, carboxyphenyl, trifluoromethylphenyl, methoxyethylphenyl, acetamidophenyl, tolyl, xylyl, dimethylcarbamylphenyl and the like. “Ph” or “PH” denotes phenyl.
[0068] Whether used alone or as part of a substituent group, “heteroaryl” refers to a cyclic, fully unsaturated radical having from five to ten ring atoms of which one ring atom is selected from S, O, and N; 0-2 ring atoms are additional heteroatoms independently selected from S, O, and N; and the remaining ring atoms are carbon. The radical may be joined to the rest of the molecule via any of the ring atoms. Exemplary heteroaryl groups include, for example, pyridinyl, pyrazinyl, pyrimidinyl, pyridazinyl, pyrroyl, pyrazolyl, imidazolyl, thiazolyl, oxazolyl, isoxazolyl, thiadiazolyl, triazolyl, triazinyl, oxadiazolyl, thienyl, furanyl, quinolinyl, isoquinolinyl, indolyl, isothiazolyl, 2-oxazepinyl, azepinyl, N-oxo-pyridyl, 1-dioxothienyl, benzothiazolyl, benzoxazolyl, benzothienyl, quinolinyl-N-oxide, benzimidazolyl, benzopyranyl, benzisothiazolyl, benzisoxazolyl, benzodiazinyl, benzofurazanyl, benzothiopyranyl, indazolyl, indolizinyl, benzofuryl, chromonyl, coumarinyl, cinnolinyl, quinoxalinyl, indazolyl, pyrrolopyridinyl, furopyridinyl (such as furo[2,3-c]pyridinyl, furo[3,2-b]pyridinyl, or furo[2,3-b]pyridinyl), imidazopyridinyl (such as imidazo[4,5-b]pyridinyl or imidazo[4,5-c]pyridinyl), naphthyridinyl, phthalazinyl, purinyl, pyridopyridyl, quinazolinyl, thienofuryl, thienopyridyl, thienothienyl, and furyl. The heteroaryl group may be substituted by independent replacement of 1 to 5 of the hydrogen atoms thereon with halogen, OH, CN, mercapto, nitro, amino, C 1 -C 8 -alkyl, C 1 -C 8 -alkoxyl, C 1 -C 8 -alkylthio, C 1 -C 8 -alkyl-amino, di(C 1 -C 8 -alkyl)amino, (mono-, di-, tri-, and per-) halo-alkyl, formyl, carboxy, alkoxycarbonyl, C 1 -C 8 -alkyl-CO—O—, C 1 -C 8 -alkyl-CO—NH—, or carboxamide. Heteroaryl may be substituted with a mono-oxo to give for example a 4-oxo-1H-quinoline.
[0069] The terms “heterocycle,” “heterocyclic,” and “heterocyclo” refer to an optionally substituted, fully or partially saturated cyclic group which is, for example, a 4- to 7-membered monocyclic, 7- to 11-membered bicyclic, or 10- to 15-membered tricyclic ring system, which has at least one heteroatom in at least one carbon atom containing ring. Each ring of the heterocyclic group containing a heteroatom may have 1, 2, or 3 heteroatoms selected from nitrogen atoms, oxygen atoms, and sulfur atoms, where the nitrogen and sulfur heteroatoms may also optionally be oxidized. The nitrogen atoms may optionally be quaternized. The heterocyclic group may be attached at any heteroatom or carbon atom.
[0070] Exemplary monocyclic heterocyclic groups include pyrrolidinyl; oxetanyl; pyrazolinyl; imidazolinyl; imidazolidinyl; oxazolyl; oxazolidinyl; isoxazolinyl; thiazolidinyl; isoth iazolidinyl; tetrahydrofu ryl; piperidinyl; piperazinyl; 2-oxopiperazinyl; 2-oxopiperidinyl; 2-oxopyrrolidinyl; 4-piperidonyl; tetrahydropyranyl; tetrahydrothiopyranyl; tetrahydrothiopyranyl sulfone; morpholinyl; thiomorpholinyl; thiomorpholinyl sulfoxide; thiomorpholinyl sulfone; 1,3-dioxolane; dioxanyl; thietanyl; thiiranyl; and the like. Exemplary bicyclic heterocyclic groups include quinuclidinyl; tetrahydroisoquinolinyl; dihydroisoindolyl; dihydroquinazolinyl (such as 3,4-dihydro-4-oxo-quinazolinyl); dihydrobenzofuryl; dihydrobenzothienyl; dihydrobenzothiopyranyl; dihydrobenzothiopyranyl sulfone; dihydrobenzopyranyl; indolinyl; isochromanyl; isoindolinyl; piperonyl; tetrahydroquinolinyl; and the like.
[0071] Substituted aryl, substituted heteroaryl, and substituted heterocycle may also be substituted with a second substituted-aryl, a second substituted-heteroaryl, or a second substituted-heterocycle to give, for example, a 4-pyrazol-1-yl-phenyl or 4-pyridin-2-yl-phenyl.
[0072] Designated numbers of carbon atoms (e.g., C 1-8 ) shall refer independently to the number of carbon atoms in an alkyl or cycloalkyl moiety or to the alkyl portion of a larger substituent in which alkyl appears as its prefix root.
[0073] Unless specified otherwise, it is intended that the definition of any substituent or variable at a particular location in a molecule be independent of its definitions elsewhere in that molecule. It is understood that substituents and substitution patterns on the compounds of this invention can be selected by one of ordinary skill in the art to provide compounds that are chemically stable and that can be readily synthesized by techniques known in the art as well as those methods set forth herein.
[0074] Where the compounds according to this invention have at least one stereogenic center, they may accordingly exist as enantiomers. Where the compounds possess two or more stereogenic centers, they may additionally exist as diastereomers. Furthermore, some of the crystalline forms for the compounds may exist as polymorphs and as such are intended to be included in the present invention. In addition, some of the compounds may form solvates with water (i.e., hydrates) or common organic solvents, and such solvates are also intended to be encompassed within the scope of this invention.
[0075] Some of the compounds of the present invention may have trans and cis isomers. In addition, where the processes for the preparation of the compounds according to the invention give rise to mixture of stereoisomers, these isomers may be separated by conventional techniques such as preparative chromatography. The compounds may be prepared as a single stereoisomer or in racemic form as a mixture of some possible stereoisomers. The non-racemic forms may be obtained by either synthesis or resolution. The compounds may, for example, be resolved into their components enantiomers by standard techniques, such as the formation of diastereomeric pairs by salt formation. The compounds may also be resolved by covalent linkage to a chiral auxiliary, followed by chromatographic separation and/or crystallographic separation, and removal of the chiral auxiliary. Alternatively, the compounds may be resolved using chiral chromatography.
[0076] This invention will be better understood by reference to the Experimental Details which follow, but those skilled in the art will readily appreciate that these are only illustrative of the invention as described more fully in the claims which follow thereafter. Additionally, throughout this application, various publications are cited. The disclosure of these publications is hereby incorporated by reference into this application to describe more fully the state of the art to which this invention pertains.
Experimental Details
I. General Synthetic Schemes
[0077] Representative compounds of the present invention can be synthesized in accordance with the general synthetic methods described below and illustrated in the following general schemes. The products of some schemes can be used as intermediates to produce more than one of the instant compounds. The choice of intermediates to be used to produce subsequent compounds of the present invention is a matter of discretion that is well within the capabilities of those skilled in the art.
[0078] Procedures described in Schemes 1 to 7, wherein R 3a , R 3b , R 3c , and R 3d are independently any R 3 group, and R 1 , R 2 , R 3 , and R 4 are as described above, can be used to prepare compounds of the invention.
[0079] The substituted pyrimidines 1 can be prepared as shown in Scheme 1. The indanone or indandione 2 or the indene ester 3 can be condensed with an aldehyde to yield the substituted benzylidenes 4 (Bullington, J. L.; Cameron, J. C.; Davis, J. E.; Dodd, J. H.; Harris, C. A.; Henry, J. R.; Pellegrino-Gensey, J. L.; Rupert, K. C.; Siekierka, J. J. Bioorg. Med. Chem. Lett. 1998, 8, 2489; Petrow, V.; Saper, J.; Sturgeon, B. J. Chem. Soc. 1949, 2134). This is then condensed with guanidine carbonate to form the indenopyrimidine 1.
[0080] Alternatively, the pyrimidine compounds can be prepared as shown in Scheme 2. Sulfone 6 can be prepared by oxidation of the thiol ether 5 and the desired amines 7 can be obtained by treatment of the sulfone with aromatic amines.
[0081] Pyrimidines with substituents on the fused aromatic ring could also be synthesized by the following procedure (Scheme 3). The synthesis starts with alkylation of furan with allyl bromide to provide 2-allylfuran. Diels-Alder reaction of 2-allylfuran with dimethylacetylene dicarboxylate followed by deoxygenation (Xing, Y. D.; Huang, N. Z. J. Org. Chem. 1982, 47,140) provided the phthalate ester 8. The phthalate ester 8 then undergoes a Claisen condensation with ethyl acetate to give the styryl indanedione 9 after acidic workup (Buckle, D. R.; Morgan, N. J.; Ross, J. W.; Smith, H.; Spicer, B. A. J. Med. Chem. 1973, 16, 1334). The indanedione 9 is then converted to the dimethylketene dithioacetal 10 using carbon disulfide in the presence of KF. Addition of Grignard reagents to the dithioacetal 10 and subsequent reaction with guanidine provides the pyrimidines 11 as a mixture of isomers.
[0082] Dihydroxylation and oxidation give the aromatic aldehydes 13 that can be reductively aminated to provide amines 14. The other isomer can be treated in a similar manner.
[0083] 3-Dicyanovinylindan-1-one (15) (Scheme 5) was obtained using the published procedure (Bello, K. A.; Cheng, L.; Griffiths, J. J. Chem. Soc., Perkin Trans. 11 1987, 815). Reaction of 3-dicyanovinylindan-1-one with an aldehyde in the presence of ammonium hydroxide produced dihydropyridines 16 (El-Taweel, F. M. A.; Sofan, M. A.; E. Maati, T. M. A.; Elagamey, A. A. Boll. Chim. Farmac. 2001, 140, 306). These compounds were then oxidized to the corresponding pyridines 17 using chromium trioxide in refluxing acetic acid.
[0084] The ketone of pyridines 17 can be reduced to provide the benzylic alcohols 18. Alternatively, the nitriles can be hydrolyzed with sodium hydroxide to give the carboxylic acids 19 (Scheme 6).
[0085] The acids can then be converted to carboxylic esters 20 or amides 21 using a variety of methods. In general, the esters 20 are obtained by treatment with silver carbonate followed by an alkyl chloride or by coupling with diethylphosphoryl cyanide (DEPC) and the appropriate alcohol (Okawa, T.; Toda, M.; Eguchi, S.; Kakehi, A. Synthesis 1998, 1467). The amides 21 are obtained by coupling the carboxylic acid with the appropriate amine in the presence of DEPC or 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (EDCI). Esters 20 can also be obtained by first reacting the carboxylic acids 19 with a dibromoalkane followed by displacement of the terminal bromide with an amine (Scheme 7).
II. Specific Compound Syntheses
[0086] Specific compounds which are representative of this invention can be prepared as per the following examples. No attempt has been made to optimize the yields obtained in these reactions. Based on the following, however, one skilled in the art would know how to increase yields through routine variations in reaction times, temperatures, solvents and/or reagents.
[0087] The products of certain syntheses can be used as intermediates to produce more than one of the instant compounds. In those cases, the choice of intermediates to be used to produce compounds of the present invention is a matter of discretion that is well within the capabilities of those skilled in the art.
EXAMPLE 1
Synthesis of Benzylidene 4
(R 2 =2-furyl, R 3a =F, R 3b , R 3c ,R 3d =H)
[0088] A mixture of 3 (3.0 g, 11.69 mmol) and 2-furaldehyde (1.17 g, 12.17 mmol) in 75 mL of ethanol and 3 mL of concentrated hydrogen chloride was allowed to stir at reflux for 16 hours. The reaction was then cooled to room temperature, and the resulting precipitate was filtered off, washed with ethanol, diethyl ether, and air dried to afford 1.27 g (45%) of product.
EXAMPLE 2
[0089]
Synthesis of Indenopyrimidine 1
(R 2 =2-furyl, R3a=F, R 3b ,R 3c ,R 3d =H)
[0090] A mixture of 4 (0.5 g, 2.06 mmol), guanidine carbonate (0.93 g, 5.16 mmol), and 20.6 mL of 0.5 M sodium methoxide in methanol was stirred at reflux for 16 hours. The reaction mixture was cooled to room temperature, and diluted with water. The resulting precipitate was collected, washed with water, ethanol, diethyl ether, and then dried. Crude material was then purified over silica gel to afford 0.024 g (4%) of product. MS m/z282.0 (M+H).
EXAMPLE 3
Synthesis of 2-Amino-4-methanesulfonyl-indeno[1,2-d]pyrimidin-5-one
[0091] To a suspension of 5 (Augustin, M.; Groth, C.; Kristen, H.; Peseke, K.; Wiechmann, C. J. Prakt. Chem. 1979, 321, 205) (1.97 g, 8.10 mmol) in MeOH (150 mL) was added a solution of oxone (14.94 g, 24.3 mmol) in H 2 O (100 mL). The mixture was stirred at room temperature overnight then diluted with cold H 2 O (500 mL), made basic with K 2 CO 3 and filtered. The product was washed with water and ether to give 0.88 g (40%) of sulfone 6. MS m/z 297.9 (M+Na).
EXAMPLE 4
Synthesis of Aminopyrimidine 7
(R 2 =NHPh, R 3 =H)
[0092] A mixture of sulfone 6 (0.20 g, 0.73 mmol) and aniline (0.20 g, 2.19 mmol) in N-methylpyrrolidinone (3.5 mL) was heated to 100° C. for 90 minutes. After cooling to room temperature, the mixture was diluted with EtOAc (100 mL), washed with brine (2×75 mL) and water (2×75 mL), and dried over Na 2 SO 4 . After filtration and concentration in vacuo, the residue was purified by column chromatography eluting with 0-50% EtOAc in hexane to yield 0.0883 g (42%) of product 7 . MS m/z289.0 (M+H).
EXAMPLE 5
Synthesis of Phthalate Ester 8
[0093] A 1.37 M hexanes solution of n-BuLi (53.6 mL, 73.4 mmol) was added to a cold, −78° C., THF solution (100 mL) of furan (5.3 mL, 73.4 mmol) and the reaction was then warmed to 0° C. After 1.25 h at 0° C. neat allyl bromide (7.9 mL, 91.8 mmol) was added in one portion. After 1 h at 0° C., saturated aqueous NH 4 Cl was added and the layers were separated. The aqueous phase was extracted with EtOAc and the combined organics were washed with water and brine, dried over Na 2 SO 4 , and concentrated to give 4.6 g (58%) of 2-allylfuran which was used without further purification.
[0094] The crude allyl furan (4.6 g, 42.6 mmol) and dimethylacetylene dicarboxylate (5.2 mL, 42.6 mmol) were heated to 90° C. in a sealed tube without solvent. After 6 h at 90° C. the material was cooled and purified by column chromatography eluting with 25% EtOAc in hexanes to give 5.8 g (54%) of the oxabicycle as a yellow oil. MS m/z 251 (M+H).
[0095] Tetrahydrofuran (60 mL) was added dropwise to neat TiCl 4 (16.5 mL, 150.8 mmol) at 0° C. A 1.0 M THF solution of LiAlH 4 (60.3 mL, 60.3 mmol) was added dropwise, changing the color of the suspension from yellow to a dark green or black suspension. Triethylamine (2.9 mL, 20.9 mmol) was added and the mixture was refluxed at 75-80° C. After 45 min, the solution was cooled to rt and a THF solution (23 mL) of the oxabicycle (5.8 g, 23.2 mmol) was added to the dark solution. After 2.5 h at rt, the solution was poured into a 20% aq. K 2 CO 3 solution (200 mL) and the resulting suspension was filtered. The precipitate was washed several times with CH 2 Cl 2 and the filtrate layers were separated. The aqueous phase was extracted with CH 2 Cl 2 and the combined organics were washed with water and brine, dried over Na 2 SO 4 , concentrated, and purified by column chromatography eluting with 25% EtOAc in hexanes to give 3.5 g (64%) of the phthalate ester 8 as a yellow oil. MS m/z 235 (M+H).
EXAMPLE 6
Synthesis of Indanedione 9
[0096] A 60% dispersion of sodium hydride in mineral oil (641 mg, 16.0 mmol) was added to an EtOAc solution (3.5 mL) of the phthalate ester 8 (2.5 g, 10.7 mmol), and the resulting slurry was refluxed. After 1 h the solution became viscous so an additional 7.5 mL of EtOAc was added. After 4 h at reflux the suspension was cooled to rt and filtered to give a yellow solid. This solid was added portionwise to a solution of HCl (25 mL water and 5 mL conc. HCl) at 80° C. The suspension was heated for an additional 30 min at 80° C., cooled to rt, and filtered to give 1.2 g (60%) of the indanedione 9 as a yellow solid. MS m/z 187 (M+H).
EXAMPLE 7
Synthesis of Dimethylketene Dithioacetal 10
[0097] Solid potassium fluoride (7.5 g, 129.1 mmol) was added to a 0° C. solution of indanedione 9 (1.2 g, 6.5 mmol) and CS 2 (0.47 mL, 7.8 mmol) in DMF (10 mL). The cold bath was removed and after 30 min neat iodomethane (1.00 mL, 16.3 mmol) was added. After 5 h at rt, the suspension was diluted with EtOAc and then washed with water and brine. The organic layer was dried over Na 2 SO 4 , concentrated, and purified by column chromatography eluting with 20% EtOAc in hexanes to give 1.4 g (75%) of the dimethylketene dithioacetal 10 as a yellow solid. MS m/z 291 (M+H).
EXAMPLE 8
Synthesis of Pyrimidine 11
(R 2 =Ph,R 3a =CHCHCH3,R 3d= H)
[0098] A 2.0 M solution of PhMgCI in THF (13 mL, 25.7 mmol) was added to a −78° C. solution of dimethylketene dithioacetal 10 (5.7 g, 19.8 mmol) in 200 mL of THF. After 3 h at −78° C., saturated aqueous NH 4 Cl was added and the layers were separated. The aqueous layer was extracted with EtOAc and the combined organic extracts were washed with water and brine, dried over Na 2 SO 4 , concentrated, and purified by column chromatography eluting with 20% EtOAc in hexanes to give 4.9 g (77%) of the thioenol ether as a yellow solid. MS m/z 321 (M+H).
[0099] Solid guanidine hydrochloride (1.5 g, 15.3 mmol) was added to a solution of the thioenol ether (4.9 g, 15.3 mmol) and K 2 CO 3 (2.6 g, 19.1 mmol) in 30 mL of DMF and the solution was heated to 80° C. After 6 h at 80° C., the solution was diluted with EtOAc and washed with water and brine. The organic layer was dried over Na 2 SO 4 , concentrated, and purified by column chromatography eluting with 40% EtOAc in hexanes to give 4.6 g (96%) of the pyrimidine regioisomers 11 as yellow solids. MS m/z 314 (M+H).
EXAMPLE 9
Synthesis of Aldehyde 13
(R 2 =Ph)
[0100] Solid MeSO 2 NH 2 (277 mg, 2.9 mmol) was added to a t-BuOH:H 2 O (1:1) solution (30 mL) of AD-mix-α (4.0 g). The resulting yellow solution was added to an EtOAc solution (15 mL) of the pyrimidine (910 mg, 2.9 mmol). After 3 days, solid sodium sulfite (4.4 g, 34.9 mmol) was added. After stirring for 1.5 h, the heterogeneous solution was diluted with EtOAc and the layers were separated. The aqueous phase was extracted with EtOAc and the combined extracts were washed with water and brine, dried over Na 2 SO 4 , concentrated, and purified by column chromatography eluting with 100% EtOAc to give 710 mg (70%) of the intermediate diol 12. MS m/z 348 (M+H).
[0101] Solid HlO 4 -2H 2 O (933 mg, 4.1 mmol) was added to a 0° C. solution of diol 12 (710 mg, 2.1 mmol) in THF. After 1.5 h at 0° C., the solution was diluted with EtOAc and the organic phase was washed with saturated aqueous NaHCO 3 , water, and brine. The organic layer was dried over Na 2 SO 4 and concentrated to give 603 mg (98%) of aldehyde 13 as a yellow solid that was used without further purification. MS m/z 302 (M+H).
EXAMPLE 10
Synthesis of Amine 14 via Reductive Amination
(R 3a =N(—CH 2 CH 2 OCH 2 CH 2 —)
[0102] Solid NaBH(OAc) 3 (53 mg, 0.25 mmol) was added to a solution of aldehyde 13 (50 mg, 0.17 mmol), morpholine (0.034 mL, 0.34 mmol), and AcOH (0.014 mL, 0.25 mmol) in 1 mL of THF. After 3 d the solution was filtered and concentrated. The resulting material was dissolved in CH 2 Cl 2 and washed with saturated aqueous NaHCO 3 and brine, dried over Na 2 SO 4 , concentrated, and purified by column chromatography eluting with 0-10% MeOH in CH 2 Cl 2 to give 38 mg (60%) of the amine 14 as a yellow solid. MS m/z 373 (M+H). The product was dissolved in a minimum amount of CH 2 Cl 2 and treated with 1.0 M HCl in ether to obtain the hydrochloride salt.
EXAMPLE 11
Cyclization to Form Dihydropyridine 16
(R 2 =2-furyl,R 3 =H)
[0103] To a solution of 3-dicyanovinylindan-1-one (4.06 g, 20.9 mmol) in 200 mL of ethanol was added 2-furaldehyde (3.01 g, 31.4 mmol) and 25 mL of conc. NH 4 OH. The solution was heated to reflux for 2 h and allowed to cool to rt overnight. The mixture was concentrated in vacuo to remove ethanol. The residue was filtered and washed with water. The purple solid obtained was dried to yield 5.92 g (89%). MS m/z 290 (M + +1).
EXAMPLE 12
Oxidation of Dihydropyridine 16 to Pyridine 17
(R 2 =2-furyl,R 3 =H,R 4 =NH 2 ,R 5 =CN,X═O)
[0104] To a refluxing solution of dihydropyridine 16 (5.92 g, 20.4 mmol) in acetic acid (100 mL) was added a solution of chromium (VI) oxide (2.05 g, 20.4 mmol) in 12 mL of water. After 10 minutes at reflux, the reaction was diluted with water until a precipitate started to form. The mixture was cooled to room temperature and filtered. The residue was washed with water to give 4.64 g (79%) of a brown solid. MS m/z 288 (M + +1).
EXAMPLE 13
Reduction of Ketone 17 to Alcohol 18
(R 2=2 -furyl,R 3 =H,R 4 =NH 2 ,R 5 =CN, X═H,OH)
[0105] To a 0° C. solution of ketone 17 (0.115 g, 0.40 mmol) in 12 mL of THF was added a 1.0 M LiAlH 4 solution in THF (0.40 mL, 0.40 mmol). The reaction was stirred at 0° C. for 1 h. The reaction was quenched by the addition of ethyl acetate (1.5 mL), water (1.5 mL), 10% aq. NaOH (1.5 mL), and saturated aq. NH 4 Cl (3.0 mL). The mixture was extracted with ethyl acetate (3×35 mL), washed with brine, and dried over sodium sulfate. The remaining solution was concentrated to yield 0.083 g (72%) of a yellow solid. MS m/z 290 (M + +1).
EXAMPLE 14
Hydrolysis of Nitrile 17 to Carboxylic Acid 19
(R 2 =2-furyl, R 3 =H, R 4 =NH 2 , R 5 =COOH, X═O)
[0106] To a mixture of nitrile 17 (0.695 g, 2.42 mmol) and ethanol (30 mL) was added 5 mL of 35% aqueous sodium hydroxide. The resulting mixture was heated to reflux overnight. After cooling to rt, the solution was poured into water and acidified with 1 N HCl. The resulting precipitate was isolated by filtration and washed with water to yield 0.623 g (84%) of a brown solid. MS m/z 329 (M + +23).
EXAMPLE 15
Synthesis of Carboxylic Ester 20 with Silver Carbonate
(R 2 =2-furyl, R 3 =H, R 4 =NH 2 , R 5 =CO 2 CH 2 CH 2 NMe 2 ,X═O)
[0107] A suspension of carboxylic acid 19 (5.0 g, 16.3 mmol), silver carbonate (5.8 g, 21.2 mmol), and tetrabutylammonium iodide (1.5 g, 4.1 mmol) in 80 mL of DMF was heated to 90° C. After 1 h, the mixture was cooled to rt and 2-(dimethylamino)ethylchloride hydrochloride (2.4 g, 16.3 mmol) was added and the mixture was heated to 100° C. After 7 h, the reaction was filtered while hot, concentrated and purified by column chromatography eluting with 0-10% MeOH/CH 2 Cl 2 to yield 0.160 g (3%) of a yellow solid. MS m/z 378 (M + +1). The product was dissolved in a minimum of dichloromethane and treated with 1.0 M HCl in ether to obtain the hydrochloride salt.
EXAMPLE 16
Synthesis of Carboxylic Ester 20 with DEPC
(R 2 =2-furyl, R 3 =H, R 4 =NH 2 , R 5 =CO 2 CH 2 CH(—CH 2 CH 2 CH 2 (Me)N—),X═O)
[0108] To a mixture of carboxylic acid 19 (0.40 g, 1.3 and (S)- 1- -methyl-2-pyrrolidinemethanol (0.50 mL, 3.9 mmol) in DMF (30 mL) was added 0.20 mL (1.3 mmol) of diethylphosphoryl cyanide and triethylamine (0.20 mL, 1.3 mmol). The reaction was stirred at 0° C. for one hour and then heated up to approximately 70° C. overnight. The reaction was then cooled to rt and diluted with ethyl acetate. The organic mixture was washed with saturated aqueous NaHCO 3 , water, and brine. After being dried with sodium sulfate, the solution was concentrated. The residue was purified by column chromatography eluting with 10-100% ethyl acetate in hexane and then preparative TLC eluting with 2% MeOH in dichloromethane to yield 1.9 mg (0.4%) of a yellow solid. MS m/z 404 (M + +1).
EXAMPLE 17
Synthesis of Carboxylic Amide 21 with DEPC
(R 2 =2-furyl, R 3 =H, R 4 =NH 2 ,R 5 =CO 2 CH 2 CH(—CH 2 CH 2 CH 2 (Me)N—),X═O)
[0109] To a mixture of carboxylic acid 19 (0.25 g, 0.82 mmol) and N,N,N′-trimethylethylenediamine (0.14 mL, 1.08 mmol) in DMF (20 mL) was added 0.12 mL (0.82 mmol) of diethylphosphoryl cyanide and triethylamine (0.11 mL, 0.82 mmol). The reaction was stirred at 0° C. for one hour and then heated up to approximately 60° C. overnight. The reaction was then cooled to rt and diluted with ethyl acetate. The organic mixture was washed with saturated aqueous NaHCO 3 , water, and brine. After being dried with magnesium sulfate, the solution was concentrated. The residue was purified by column chromatography eluting with 0-10% methanol in dichloromethane and then preparative TLC eluting with 1% MeOH in dichloromethane to yield 3.3 mg (10%) of a yellow solid. MS m/z 391 (M + +1). The product was dissolved in a minimum of diethyl ether and treated with 1.0 M HCl in ether to obtain the hydrochloride salt.
EXAMPLE 18
Synthesis of Carboxylic Amide 21 with EDCI
(R 2=2 -furyl, R 3 =H, R 4 =NH 2 , R 5 =CON(—CH 2 CH 2 NMeCH 2 CH 2 -),X═O)
[0110] A mixture of carboxylic acid 19 (0.300 g, 0.979 mmol), N-methylpiperazine (0.295 g, 2.94 mmol), 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (0.563 g, 2.94 mmol) 1-hydroxybenzotriazole hydrate (0.397 g, 2.94 mmol), triethylamine (0.298 g, 2.94 mmol) in DMF (8 mL) was stirred at rt overnight. The mixture was then diluted with water and extracted several times with ethyl acetate. The combined organics were washed twice with brine and then dried over sodium sulfate. The solution was concentrated and then purified by column chromatography to afford 0.092 g (2%) of solid. MS m/z 389 (M + +1). The product was treated with 1.0 M HCl in ether to obtain the hydrochloride salt.
EXAMPLE 19
Synthesis of Carboxylic Ester 20 via a Dibromoalkane
(R 2 =Ph, R 3 =H, R 4 =NH 2 , R 5 =CO 2 CH 2 CH 2 CH 2 NMe 2 ,X═O)
[0111] To a solution of carboxylic acid 19 (0.100 g, 0.32 mmol) in DMF (1.5 mL) was added 60% NaH dispersion in mineral oil (0.013 g, 0.32 mmol). After 10 min at rt, 1,3-dibromopropane (0.035 mL, 0.35 mmol) was added and the solution was stirred at rt for 17 h. After concentration, the residue was purified via column chromatography eluting with 40% ethyl acetate in hexanes to yield 0.014 g (9%) of a yellow solid. MS m/z 437 (M + +1).
[0112] To a solution of the yellow solid (0.014 mg, 0.03 mmol) in a sealed tube was added a 40% aqueous solution of dimethylamine (0.5 mL, 3.0 mmol). The tube was heated to 75° C. for 2 h before concentrating. The residue was purified by column chromatography eluting with 0-10% methanol in dichloromethane to yield 0.009 g (70%) of a yellow solid. MS m/z 402 (M + +1). The productwas dissolved in a minimal amount of CH 2 Cl 2 and treated with 1 N HCl in ether to obtain the hydrochloride salt.
[0113] Following the general synthetic procedures outlined above and in Examples 1-19, the compounds of Table 1 below were prepared.
TABLE 1 No. R 2 R 3a R 3b R 3c R 3d R 4 X MS (M + 1) 1 4-MeOPh H H H H NH 2 CH 2 290 2 4-MeOPh H H H H NH 2 CO 304 3 2-furyl H H H H NH 2 CO 264 4 2-furyl H H H H NH 2 CH 2 250 5 3-pyridyl H H H H NH 2 CO 297 (+Na) 6 4-pyridyl H H H H NH 2 CO 275 7 H H H H NH 2 CO 281 C 3 H 2 NS 8 4-ClC 6 H 4 H H H H NH 2 CO 308 9 3-NO 2 C 6 H 4 H H H H NH 2 CO 319 10 Ph H H H H NH 2 CO 274 11 3-MeOC 6 H 4 H H H H NH 2 CO 304 12 2-MeOC 6 H 4 H H H H NH 2 CO 304 13 3-HOC 6 H 4 H H H H NH 2 CO 290 14 2-thiophenyl H H H H NH 2 CO 302 15 3-thiophenyl H H H H NH 2 CO 302 16 2-furyl H Br H H NH 2 CO 342 17 2-furyl OH H H H NH 2 CO 280 18 SCH 3 NH 2 H H H NH 2 CO 259 19 3-FC 6 H 4 H H H H NCHNMe 2 CO 347 20 2-furyl NH 2 H H H NH 2 CO 279 21 2-furyl H H H NH 2 NH 2 CO 279 22 2-furyl H CF 3 H H NH 2 CO 332 23 2-furyl H H CF 3 H NH 2 CO 332 24 Ph H H H H NHMe CO 288 25 2-furyl H Cl Cl H NH 2 CO 332 26 2-furyl Cl H H Cl NH 2 CO 332 27 Ph H H H HN(CH 2 ) 2 NEt 2 CO 373 28 3,4-F 2 C 6 H 3 H H H H NH 2 CO 310 29 3,5-F 2 C 6 H 3 H H H H NH 2 CO 310 30 H H H H NH 2 CO 305 C 6 H 6 NO 31 3,4,5-F 3 C 2 H 2 H H H H NH 2 CO 340 (M + Na) 32 Ph H H H NH 2 CO 348 C 3 H 7 O 2 33 Ph H H H NH 2 CO 348 C 3 H 7 O 2 34 H H H H NH 2 CO 333 C 8 H 10 NO 35 2-furyl H H Br H NH 2 CO 342/344 36 2-furyl H H H F NH 2 CO 282 37 2-furyl MeO H H H NH 2 CO 294 38 4-FC 6 H 4 H H H H NH 2 CO 292 39 3-FC 6 H 4 H H H H NH 2 CO 292 40 SO 2 Me H H H H NH 2 CO 298 41 Sme H H H H NH 2 CO 266 42 Ome H H H H NH 2 CO 477 (2M + Na) 43 NHPh H H H H NH 2 CO 289 44 3-furyl H H H H NH 2 CO 264 45 5-methyl-2-furyl H H H H NH 2 CO 278 46 2-furyl OCH 2 CH 2 NHCO 2 tBu H H H NH 2 CO 437 47 Ph H H H H Me CO 297 48 Ph H H H H OMe CO 291 49 Ph CH 2 NMeCH 2 CH 2 NMe 2 H H H NH 2 CO 388 50 Ph H H H NH 2 CO 386 C 6 H 13 N 2 51 Ph H H H NH 2 CO 373 C 5 H 10 NO 52 Ph CH 2 NEt 2 H H H NH 2 CO 359 53 Ph H H H NH 2 CO 371 C 6 H 12 N 54 Ph H H H NH 2 CO 429 C 8 H 14 NO 2 55 Ph H H H NH 2 CO 443 C 9 H 16 NO 2 56 Ph CH 2 NMeCH 2 CO 2 Me H H H NH 2 CO 389 57 Ph H H H NH 2 CO 401 C 7 H 14 NO416 58 Ph H H H NH 2 CO 416 C 7 H 15 N 2 O 59 Ph H H H NH 2 CO 414 C 7 H 13 N 2 O 60 Ph H H H NH 2 CO 486 C 11 H 21 N 2 O 2 61 Ph H H H NH 2 CO 422 C 9 H 13 N 2 62 Ph H H H NH 2 CO 397 C 7 H 10 NO
[0114]
TABLE 2
No.
X
R 2
R 3a
R 3b
R 3c
R 3d
R 1
MS (M + 1)
63
CO
2-furyl
H
H
H
H
CN
288
64
CO
Ph
H
H
H
H
CN
298
65
CO
Ph
H
H
H
H
COOH
315 (M − 1)
66
CO
3-furyl
H
H
H
H
CN
288
67
CO
3-FC 6 H 4
H
H
H
H
CN
316
68
CO
3-pyridyl
H
H
H
H
CN
299
69
CO
2-furyl
H
H
H
H
COOH
305 (M − 1)
70
CO
2-furyl
H
H
H
H
CO 2 CH 2 CH 2 NMe 2
378
71
CO
4-FC 6 H 4
H
H
H
H
CN
316
72
CO
2-thiophenyl
H
H
H
H
CN
304
73
CO
3-thiophenyl
H
H
H
H
CN
304
74
CO
3-MeOC 6 H 4
H
H
H
H
CN
328
75
CO
2-imidazolyl
H
H
H
H
CN
288
76
CO
2-furyl
H
H
H
H
CONHCH 2 CH 2 NMe 2
377
77
CO
2-furyl
H
H
H
H
CONMeCH 2 CH 2 NMe 2
391
78
CO
2-furyl
H
H
H
H
CONHCHMeCH 2 NMe 2
391
79
CO
2-furyl
F
F
F
F
CN
358 (M − 1)
80
CO
2-furyl
H
H
H
H
389
C 6 H 4 NO 2 C 6 H 11 N 2 O
81
CO
Ph
H
H
H
H
CO 2 CH 2 CH 2 NMe 2
388
82
CO
2-furyl
H
H
H
H
404
C 7 H 12 NO 2
83
CO
Ph
H
H
H
H
457
C 9 H 17 N 2 O 2
84
CO
Ph
H
H
H
H
444
C 8 H 14 NO 3
85
CO
Et
H
H
H
H
CN
250
86
CO
i-Bu
H
H
H
H
CN
278
87
CO
Ph
H
H
H
H
CO 2 CH 2 CH 2 CH 2 NMe 2
402
88
CO
Ph
H
H
H
H
414
C 7 H 12 NO 2
89
CHOH
2-furyl
H
H
H
H
CN
290
90
CO
Ph
H
H
H
H
414
C 7 H 12 NO 2
91
CO
Ph
H
H
H
H
430
C 7 H 12 NO 2
92
CO
Ph
H
H
H
H
CO 2 CH 2 CHMeCH 2 NMe 2
416
93
CO
3-thiophenyl
H
H
H
H
CO 2 CH 2 CH 2 NMe 2
394
94
CO
CH 2 CH 2 CHCH 2
H
H
H
H
CN
276
95
CO
c-Hex
H
H
H
H
CN
302 (M − 1)
96
CO
2-furyl
H
H
H
H
(S)-CO 2 CHMeCH 2 NMe 2
392
III. Biological Assays and Activity
Ligand Binding Assay for Adenosine A2a Receptor
[0115] Ligand binding assay of adenosine A2a receptor was performed using plasma membrane of HEK293 cells containing human A2a adenosine receptor (PerkinElmer, RB-HA2a) and radioligand [ 3 H]CGS21680 (PerkinElmer, NET1021). Assay was set up in 96-well polypropylene plate in total volume of 200 μL by sequentially adding 20 μL 1:20 diluted membrane, 130 μLassay buffer (50 mM Tris.HCl, pH7.4 10 mM MgCl 2 , 1 mM EDTA) containing [ 3 H] CGS21680, 50 μL diluted compound (4×) or vehicle control in assay buffer. Nonspecific binding was determined by 80 mM NECA. Reaction was carried out at room temperature for 2 hours before filtering through 96-well GF/C filter plate pre-soaked in 50 mM Tris.HCl, pH7.4 containing 0.3% polyethylenimine. Plates were then washed 5 times with cold 50 mM Tris.HCl, pH7.4, dried and sealed at the bottom. Microscintillation fluid 30 μl was added to each well and the top sealed. Plates were counted on Packard Topcount for [ 3 H]. Data was analyzed in Microsoft Excel and GraphPad Prism programs. (Varani, K.; Gessi, S.; Dalpiaz, A.; Borea, P. A. British Journal of Pharmacology, 1996, 117,1693)
Adenosine A2a Receptor Functional Assay
[0116] CHO—K1 cells overexpressing human adenosine A2a receptors and containing cAMP-inducible beta-galactosidase reporter gene were seeded at 40-50K/well into 96-well tissue culture plates and cultured for two days. On assay day, cells were washed once with 200 μL assay medium (F-12 nutrient mixture/0.1% BSA). For agonist assay, adenosine A2a receptor agonist NECA was subsequently added and cell incubated at 37° C., 5% CO 2 for 5 hrs before stopping reaction. In the case of antagonist assay, cells were incubated with antagonists for 5 minutes at R.T. followed by addition of 50 nM NECA. Cells were then incubated at 37° C., 5% CO 2 for 5 hrs before stopping experiments by washing cells with PBS twice. 50 μL 1× lysis buffer (Promega, 5× stock solution, needs to be diluted to 1× before use) was added to each well and plates frozen at −20° C. For β-galactosidase enzyme colorimetric assay, plates were thawed out at room temperature and 50 μL 2× assay buffer (Promega) added to each well. Color was allowed to develop at 37° C. for 1 h or until reasonable signal appeared. Reaction was then stopped with 150 μL 1M sodium carbonate. Plates were counted at 405 nm on Vmax Machine (Molecular Devices). Data was analyzed in Microsoft Excel and GraphPad Prism programs. (Chen, W. B.; Shields, T. S.; Cone, R. D. Analytical Biochemistry, 1995, 226, 349; Stiles, G. Journal of Biological Chemistry, 1992, 267, 6451)
Haloperidol-Induced Catalepsy Study in C57bl/6 Mice
[0117] Mature male C57bl/6 mice (9-12 week old from ACE) were housed two per cage in a rodent room. Room temperature was maintained at 64-79 degrees and humidity at 30-70% and room lighting at 12 hrs light/12 hrs dark cycle. On the study day, mice were transferred to the study room. The mice were injected subcutaneously with haloperidol (Sigma H1512, 1.0 mg/ml made in 0.3% tartaric acid, then diluted to 0.2 mg/ml with saline) or vehicle at 1.5 mg/kg, 7.5 ml/kg. The mice were then placed in their home cages with access to water and food. 30 minutes later, the mice were orally dosed with vehicle (0.3% Tween 80 in saline) or compounds at 10 mg/kg, 10 ml/kg (compounds, 1 mg/ml, made in 0.3% Tween 80 in saline, sonicated to obtain a uniform suspension). The mice were then placed in their home cages with access to water and food. 1 hour after oral dose, the catalepsy test was performed. A vertical metal-wire grid (1.0 cm squares) was used for the test. The mice were placed on the grid and given a few seconds to settle down and their immobility time was recorded until the mice moved their back paw(s). The mice were removed gently from the grid and put back on the grid and their immobility time was counted again. The measurement was repeated three times. The average of three measurements was used for data analysis.
[0118] Compound 70 showed 87% inhibition and compound 3 showed 90% inhibition of haloperidol-induced catalepsy when orally dosed at 10 mg/kg.
TABLE 5 Ki (nM) A2a A1 A2a antagonist antagonist No. binding function function 1 44.64 233.7 52.98 2 2.032 6.868 5.32 3 0.26 0.0066 0.288 4 0.885 2.63 15.57 5 5.355 9.64 27.1 6 3.9 4.56 16.44 7 0.26 0.49 6.89 8 58.41 5.5 11.59 9 20.82 4.85 7.69 10 6.1 0.109 1.2 11 8.85 1.63 2.47 12 33.49 32.52 172.3 13 5.16 35.59 10.35 14 2.19 0.59 3.19 15 3.23 0.258 3.46 16 1.75 0.169 5.22 17 6.3 67.14 111.29 18 317.95 >3000 188.99 19 110.73 20.88 21.64 20 0.05 0.126 0.91 21 0.376 0.053 3.51 22 14.16 0.055 2.75 23 13.58 0.55 1.47 24 30.32 >3000 5.99 25 172.85 5.69 17.44 26 34.57 0.88 3.13 27 146.84 68.28 >1000 28 48.9 3.53 5.86 29 20.95 1.42 4.27 30 31.55 10.15 4.05 31 140.68 15.22 17.5 32 3.55 0.634 9.89 33 0.175 0.34 0.021 34 560.13 35 3.49 0.265 7.09 36 4.37 0.052 2.52 37 2.86 0.143 3.07 38 2.34 0.956 9.44 39 4.92 0.926 2.31 40 2720.46 41 88.01 575.43 >3000 42 118.2 782.18 >10000 43 39.9 3.68 2.34 44 3.93 0.208 7.4 45 4.013 0.005 0.016 46 60.56 490.14 32.54 47 1076.76 48 470.84 >1000 >1000 49 51.12 40.13 119.03 50 80.15 11.31 94.24 51 36.81 3.26 32.92 52 94.41 18.33 107.17 53 64.15 14.25 40.82 54 40.79 3.19 19.56 55 32.82 5.84 19.86 56 25.72 6.81 25.76 57 34.02 15.93 39.29 58 30.65 11.65 60.99 59 40.79 7.94 34.11 60 34.29 61 29.83 62 58.39 63 0.59 0.0002 0.18 64 13.09 0.138 4.61 65 574.71 244.96 163.36 66 4.21 0.069 15.59 67 13.4 0.618 4.37 68 7.59 0.73 34.84 69 2261 90.16 >1000 70 9.89 0.44 20.13 71 17.24 3.39 2.42 72 12.64 2.54 6.24 73 4.925 0.06 9.7 74 14.67 5.7 7.28 75 23.72 1.51 78.33 76 33.03 22.13 >500 77 6.254 0.68 >500 78 17.65 1.58 >500 79 8.03 12.48 >1000 80 69.08 15.86 55.99 81 228.7 29.03 33.63 82 20.24 1.36 29.58 83 200.06 74.87 117.05 84 173.98 24.71 27.42 85 507.72 86 244.07 >1000 39.26 87 98.93 39.45 >300 88 129.6 48.87 >300 89 5.85 1.12 11.16 90 202.17 57.7 >300 91 208.32 22.07 14.67 92 38.82 13.9 32.88 93 64.05 23.57 104.31 94 49.55 >1000 35.99 95 338.13 >1000 110.22 96 48.55 10.08 52.45 | This invention provides novel arylindenopyridines and arylindenopyrimidines of the formula:
wherein R 1 , R 2 , R 3 , R 4 , and X are as defined above, and pharmaceutical compositions comprising same, useful for treating disorders ameliorated by antagonizing adenosine A 2 a receptors. This invention also provides therapeutic and prophylactic methods using the instant compounds and pharmaceutical compositions. | 0 |
BACKGROUND OF THE INVENTION
[0001] The present application relates to methods for increasing tolerance of plants and/or their offspring to one or more stresses, in particular relating to the generation of stress tolerant plants and seeds/propagules thereof.
[0002] The ability to provide plants that are tolerant to usually unfavourable environmental conditions is highly desirable. For example, seeds that germinate into crop plants that show enhanced tolerance to drought or other water stresses than their parent(s) could be particularly useful. Moreover, it would be desirable to produce tolerant seeds/propagules for use in climates where yields are currently restricted by limited water availability.
SUMMARY OF THE INVENTION
[0003] According to one aspect of the present invention, there is provided a method for the production of a stress tolerant plant or precursor thereof, the method comprising:
[0004] (i) subjecting one or more parental plants to one or more stress conditions selected from unfavourable conditions relating to relative humidity, water availability, periodic drought, nutrients, sunlight, wind, temperature, pH, exogenous chemicals, chemical toxins such as salt, herbivory, prophylactic chemicals, fertilizers, pathogen attack such as bacterial, fungal, or virus infection and pest infestation; and
[0005] (ii) generating offspring from said one or more parental plants,
[0006] wherein said offspring show enhanced tolerance relative to the one or more parental plants to one or more stress conditions selected from unfavourable conditions relating to relative humidity, water availability, periodic drought, nutrients, sunlight, wind, temperature, pH, exogenous chemicals, chemical toxins such as salt, herbivory, prophylactic chemicals, fertilizers, pathogen attack such as bacterial, fungal, or virus infection and pest infestation.
[0007] Preferably, the offspring are adult plants or a precursor thereof such as seeds or vegetative propagules.
[0008] Remarkably, it has been found that by subjecting a parent plant to one or more stress conditions, the seed or vegetative offspring produced from that parent plant can exhibit increased tolerance to the same one or more stress conditions. It has also, remarkably, been found that the offspring may be tolerant to one or more stress conditions which differ from those experienced by the one or more parental plants. For example Arabidopsis plants exposed to slightly reduced relative humidity stress nevertheless exhibited increased tolerance to periodic drought stress (See example 2 below). Accordingly, in one embodiment, it is preferred that the offspring are tolerant to one or more stress conditions not experienced by the one or more parental plants.
[0009] It will be appreciated that the term “unfavourable” is relative to the plant in question and is a relative term. For example, for plants which usually thrive in medium or high levels of humidity, a low relative humidity may be seen as “unfavourable” and therefore as a stress condition. For example, in the context of a food crop, any condition that leads to reduction in yields, harvestable yields or in sustainable harvests may be viewed as “unfavourable”.
[0010] Preferably, the one or more stress conditions are selected from low relative humidity, periodic drought and infection with Botrytis (e.g. Botrytis cynerea ).
[0011] Preferably, the one or more parental plants are subjected to the one or more stress conditions under semi-controlled or more preferably, controlled conditions.
[0012] Preferably, the one or more parental plants are selected from a higher plant, a flowering plant and a dicotyledonous plant.
[0013] Preferably, the one or more parental plants are crop plants.
[0014] Preferably, the one or more parental plants belong to the Eudicotyledons. Preferably, the one or more parental plants are a member of the Brassicacea or the Malvaceae. Preferably, the one or more parental plants are selected from Arabidopsis plants and a Theobroma plants, for example selected from Arabidopsis thaliana and Theobroma cacao.
[0015] Preferably, the one or more parental plants are flowering plants ( Magnoliophyta ), and the one or more stress conditions are likely to impact on harvestable yield; for example including stresses associated with water availability (low relative humidity or periodic drought), to toxic chemicals (such as salt), exogenous chemicals or to exposure to pathogens (such as Botrytis ) or pests.
[0016] Preferably, the methods of the present invention are for producing plants capable of generating higher yields under one or more stress conditions experienced and/or not experienced by the one or more parental plants. For example, it is preferred that the plants produced by the methods of the present invention show increased production of biomass, flower number, seed number, seed weight at any chosen time of harvest.
[0017] As described above, the methods of the present invention can be used to produce a precursor of a stress tolerant plant such as a seed or a vegetative propagule. For example, in one aspect of the present invention there is provided a method which comprises:
[0018] (i) subjecting one or more parental plants to one or more stress conditions selected from unfavourable conditions relating to relative humidity, water availability, periodic drought, nutrients, sunlight, wind, temperature, pH, exogenous chemicals, chemical toxins such as salt, herbivory, prophylactic chemicals, fertilizers, pathogen attack such as bacterial, fungal, or virus infection and pest infestation;
[0019] (ii) generating a precursor for offspring from said one or more parental plants, wherein said precursor is capable of developing into a plant which shows increased tolerance relative to the one or more parental plants to one or more stress conditions selected from unfavourable conditions relating to relative humidity, water availability, periodic drought, nutrients, sunlight, wind, temperature, pH, exogenous chemicals, chemical toxins such as salt, herbivory, prophylactic chemicals, fertilizers, pathogen attack such as bacterial, fungal, or virus infection and pest infestation and/or is capable of generating higher yields relative to the one or more parental plants under said stress conditions.
[0020] Preferably, the precursor is a seed or a vegetative propagule such as a cutting. For example, the precursor may be an Arabidopsis seed which is capable of growing into a plant tolerant to low relative humidity and/or to periodic drought. In other examples, the precusor is a cutting or a somatic embryo of cocoa ( Theobroma cacao L.) which is capable of growing into a plant tolerant to low relative humidity and/or to periodic drought. Further examples include an Arabidopsis seed which is capable of growing into a plant with enhanced resistance to Botrytis.
[0021] Preferably, the methods of the invention comprise crossing (i.e. cross-pollinating) two parental plants or self-pollinating a single parental plant. In other examples, a vegetative propagule is created from a parental plant that has been exposed to one or more stress conditions.
[0022] Preferably, the methods of the invention comprise generating seed offspring from a single parent genotype, for example by self-pollination or by cross-pollinating one of the treated parental plants with a second (untreated) parental plant.
[0023] It will be appreciated that subjecting a parental plant to one or more stress conditions includes subjecting all or a part of the plant to one or more stress conditions. For example, in the case of low relative humidity, all of the plant could be exposed. In the case of infection with Botrytis , a single leaf or portion thereof could be exposed.
[0024] According to another aspect of the present invention, there is provided a plant, or precursor thereof, produced by a method as described herein.
[0025] As such, the present invention provides a plant or precursor thereof which is tolerant to one or more stress conditions.
[0026] Another aspect of the present invention relates to an assay for identifying a plant, or precursor thereof, produced by the methods described herein, the assay comprising analysing a plant, or precursor thereof, suspected of being produced by the method for the presence or absence of one or more sites of genomic methylation, wherein the presence or absence of methylation at said one or more sites is indicative of a plant, or precursor thereof, produced by the method.
[0027] Preferably, the method is for producing a low relative humidity and/or periodic drought-tolerant plant (for example an Arabidopsis plant), or seed thereof, and the presence of a methylation state at or within about 10 kb, preferably about 5 kb, preferably about 2 kb of a SPEECHLESS or FAMA gene, or a functional homolog of either gene, is indicative of the acquired stress-tolerance in a plant or seed produced by the methods described herein.
[0028] Another aspect of the present invention provides an assay for identifying a plant, or precursor thereof, which is tolerant to one or more stress conditions selected from unfavourable conditions relating to relative humidity, water availability, periodic drought, nutrients, sunlight, wind, temperature, pH, exogenous chemicals, chemical toxins such as salt, herbivory, prophylactic chemicals, fertilizers, pathogen attack such as bacterial, fungal, or virus infection and pest infestation, wherein the assay comprises analysing a plant, or precursor thereof for the presence or absence of one or more sites of genomic DNA methylation, wherein the presence or absence of methylation at said one or more sites is indicative of a plant, or precursor thereof, which is tolerant to said one or more stress conditions. Preferably, the presence of genomic methylation in or within about 10 kb, preferably about 5 kb, preferably about 2 kb, of a SPEECHLESS or FAMA gene, or a functional homolog of either gene, is indicative of a plant, or precursor thereof, which is tolerant to low relative humidity and/or periodic drought.
[0029] It will be seen that, according to the present invention, there is provided a method for changing the stress response of the offspring of a plant by previously exposing (prior to conception/zygote formation) one or more of its parents to the same stress(es) or a different stress (hereafter also referred to as conditioning stress[es]).
[0030] As detailed herein, in some embodiments the change to stress response in the offspring relates to a different stress type to that experienced by the parents. That is, where exposure to the conditioning stress evokes a changed response to another stress in the offspring.
[0031] Preferably, the offspring are clonal propagules of a parental plant. Put another way, it is preferred that the change in stress response is induced in a clonal propagule of the parental plant exposed to the conditioning stress(es).
[0032] As will be appreciated, the seeds of crop plants in which either or both parents have been exposed to one or more conditioning stresses are produced for the purpose of improving the stress tolerance of the plants derived from said seeds.
[0033] As will be further appreciated, in accordance with the methods of the present invention, plants which have been exposed to one or more conditioning stresses can be used to produce vegetative propagules, for example cuttings, micropropagation, callus-mediated adentitious shooting or somatic embryogenesis, with changed, preferably improved, tolerance to one or more stress conditions.
[0034] Particularly preferred examples of the invention include the following.
[0035] Preferably, the seeds of plants in which either or both parents have been exposed to low relative humidity stresses are produced for the purpose of changing (preferably improving) the tolerance of the plants derived from said seeds to water stress (examples include but are not limited to low relative humidity stress and periodic drought).
[0036] Preferably, the seeds of plants in which either or both parents have been exposed to low relative humidity stresses are produced for the purpose of changing (preferably improving) the tolerance of the plants derived from said seeds to low relative humidity stress.
[0037] Preferably, the seeds of Eudicotyledonous plants in which either or both parents have been exposed to low relative humidity stresses are produced for the purpose of improving the tolerance of the plants derived from said seeds to water stress (examples include but are not limited to low relative humidity stress and periodic drought).
[0038] Preferably, the seeds of Eudicotyledonous plants in which either or both parents have been exposed to low relative humidity stresses are produced for the purpose of changing (preferably improving) the tolerance of the plants derived from said seeds to low relative humidity stress (examples include but are not limited to low relative humidity stress and periodic drought).
[0039] Preferably, the seeds of Brassicacea or Malvaceae plants in which either or both parents have been exposed to low relative humidity stresses are produced for the purpose of improving the tolerance of the plants derived from said seeds to water stress (examples include but are not limited to low relative humidity stress and periodic drought).
[0040] Preferably, the seeds of Brassicacea or Malvaceae plants in which either or both parents have been exposed to low relative humidity stresses are produced for the purpose of changing (preferably improving) the tolerance of the plants derived from said seeds to low relative humidity stress.
[0041] Preferably, the plants which have been exposed to low relative humidity stresses are used to produce vegetative propagules with changed (preferably improved) tolerance to water stress (examples include but are not limited to low relative humidity stress and periodic drought).
[0042] Preferably, the plants which have been exposed to low relative humidity stresses are used to produce vegetative propagules with changed (preferably improved) tolerance to low relative humidity stress.
[0043] Preferably, the seeds of plants in which either or both parents have been exposed to biotic stress (examples include but not limited to exposure to pathogenic fungi) are produced for the purpose of changing (preferably improving) the resistance of the plants derived from said seeds to the same biotic stresses.
[0044] Preferably, the seeds of eudicotyledonous plants in which either or both parents have been exposed to biotic stress (examples include but not limited to exposure to pathogenic fungi) are produced for the purpose of changing (preferably improving) the resistance of the plants derived from said seeds to the same biotic stresses.
[0045] Preferably, the seeds of plants of the Brassicacea or Malvaceae in which either or both parents have been exposed to biotic stress (examples include but not limited to exposure to pathogenic fungi) are produced for the purpose of changing (preferably improving) the resistance of the plants derived from said seeds to the same biotic stresses.
[0046] Preferably, the seeds of plants in which either or both parents have been exposed to Botrytis fungi are produced for the purpose of changing (preferably improving) the resistance of the plants derived from said seeds to infection by Botrytis fungi.
[0047] Preferably, the seeds of eudicotyledonous plants in which either or both parents have been exposed to Botrytis fungi are produced for the purpose of changing (preferably improving) the resistance of the plants derived from said seeds to infection by Botrytis fungi.
[0048] Preferably, the seeds of plants of the Brassicacea or Malvaceae in which either or both parents have been exposed to Botrytis fungi are produced for the purpose of changing (preferably improving) the resistance of the plants derived from said seeds to infection by Botrytis fungi.
[0049] Preferably, the changed stress responses of plants (preferably crop plants) whose parents have been exposed to conditioning stresses (as identified above) leads to changed (preferably enhanced) production of biomass, flower number, seed number, seed weight at any chosen time of harvest.
[0050] Preferably, plants with changed tolerance to water stress are produced according to the methods described herein are detected according to changed methylation status of the DNA (measured using standard techniques including but not limited to bisulfite treatment followed by Sanger or NextGen sequencing, High Resolution Melt Analysis or Methyl capture and pPCR) encoding for the SPEECHLESS and/or FAMA genes (or functional homologue thereof) and/or of the DNA sequence immediately flanking said gene, where flanking sequence is preferably <10 kb, more preferably <3 kb and most preferably <1.5 kb of start or stop codons.
[0051] Example embodiments of the present invention will now be described with reference to the accompanying figures in which:—
[0052] FIG. 1 shows that differential stomatal index (SI) with low relative humidity treatment*parent is positively correlated with expression of the SPCH and FAMA genes and inversely correlated with DNA methylation of SPCH. Wild type (WT) SI is reduced in low relative humidity (LRH): in the progeny of the LRH-treated parent grown in LRH, however, SI is increased (ANOVA: treatment P=0.001, parent P=<0.001, interaction P=<0.001). This effect is abolished in the methyltransferase mutants met1 and drm1/2. Data shown are means (±s.e.m.) for one experiment where n=48. Expression of the SPCH and FAMA stomata pathway genes is also reduced in the parent in LRH but not in the progeny; neither is expression of SPCH nor FAMA reduced significantly by LRH in met1, drm1/2 or the siRNA mutant rdr6. Data shown are mean percentage increases in [mRNAs] from three repeated assays for each target in LRH relative to their own control (0 line of the x axis). Sequences of samples following bisulfite conversion show de novo cytosine methylation with LRH at SPCH (a—consensus 1 St generation) and FAMA (d—consensus 1 St generation) which is not reproduced in the met1 or drm1/2 mutants (b and e). This methylation is heritable in SPCH but lost in the progeny of the LRH-grown parent grown in LRH (a—consensus 2 nd generation). The pattern of differential methylation with LRH stress at the SPCH locus (TAIR v. 9.0) is shown for three generations. G1 plants (first exposure) plants are de novo methylated in all contexts under LRH stress (additional 78 sites in 4.25 kb). Progeny of these plants (G2) inherit the majority of methylation (LRH-control) but are substantially demethylated when returned to LRH stress (LRH-LRH). There is a loss of inherited methylation in the next generation (G3, LRH-control-control) including at the upstream regulatory region and transcription start sites, but this region is remethylated heritably during a second exposure to stress (LRH-LRH-control). In FIG. 1E shaded areas (outlined by dashed lines) indicate methylated regions by methyl capture+qPCR in Chromosome 5 from 21584.3 k to 21589.3 k, and bars methylated base pairs by 454 sequencing following bisulfite conversion (green=CG, blue=CHG, pink=CHH contexts). Black horizontal lines show the extent of successful 454 sequencing and methods. The boxed region indicates the region assayed at base-pair resolution by sub-cloning and sequencing following bisulfite conversion and from which representative sequences are shown in a-c;
[0053] FIG. 2 shows that (A) the size (dry weight (g) at harvest) and (B) productivity (seed number produced) of progenies are also influenced by parental experience of stress. Offspring of parents exposed to LRH stress exhibited increased size and productivity in both the LRH treatment and in control conditions (ANOVA: treatment P=<0.001, parent P=<0.001, interaction P=0.39). This effect was characteristic of all the tested progeny plants in a line (n=48 in each repeated experiment) from all exposed parents (n=3 in each experiment) in four repeated experiments;
[0054] FIGS. 3A and 3B show siRNAs concentration in LRH treatment*parent experiments. There was an increase in the total concentration of 24 nt siRNAs on first exposure to LRH and a decrease when offspring of LRH-treated parents are grown under LRH stress. Induction of siRNAs at transposable elements upstream (in the genome) of SPCH was inversely correlated with gene expression and positively correlated with methylation at SPCH;
[0055] FIG. 4 shows the effect of preconditioning with Low Relative Humidity on chlorophyll content after 4 days drought. Offspring of parents exposed to LRH stress exhibited increased chlorophyll content in both the LRH treatment and when subjected to periodic drought;
[0056] FIG. 5 shows the effect of preconditioning with Low Relative Humidity on plant dry weight after 4 days drought. Offspring of parents exposed to LRH stress exhibited increased final dry weight in both the LRH treatment and when subjected to periodic drought;
[0057] FIG. 6 shows resistance to Botrytis cynerea is increased by non-lethal innoculation on the previous generation. Generation 2 plants were treated with Botrytis cynerea . Pictures show lesions associated to fungal infection three days after inoculation in Langsberg erecta. Offspring of non-inoculated plants (A), offspring of inoculated plants (B) Arrows point inoculated leaves. Detail of the inoculated leaves from offspring of non-inoculated plants (C), offspring of inoculated plants (D);
[0058] FIG. 7 shows analysis of global methylation changes induced by infection with Botrytis cynerea using restriction enzyme MspI. DNA from five different Arabidopsis thaliana genotypes (Wild type—Laer, and methylation mutants: drm1/2, chr1, cmt3-7 and kyp2) inoculated (rhomboids) and pathogen free (circles) (24 samples each) was restricted using the enzyme combination MspI/EcoRI (sensitive to methylation on the CpHpG motif). No significant differences were found between treatments. Error bars show calculated standard deviations; and
[0059] FIG. 8 shows analysis of global methylation changes induced by infection with Botrytis cynerea using restriction enzyme MspI. DNA from five different Arabidopsis thaliana genotypes (Wild type—Laer, and methylation mutants: drm1/2, chr1, cmt3-7 and kyp2) inoculated (rhomboids) and pathogen free (circles) (24 samples each) was restricted using the enzyme combination HpaII/EcoRI (sensitive to methylation on the CpHpG and the CpG motiffs). No differences were found between treatments for genotypes Wild type—Laer and kyp2. Genotype cmt3-7 showed some degree of separation (not significant) between samples infected with Botrytis and those non-infected. Genotypes drm1/2 and chr1 showed a significant on global DNA methylation induced by the infection with Botrytis . Error bars show calculated standard deviations.
DETAILED DESCRIPTION OF THE INVENTION
[0060] The invention relates to methods for the production of plants and precursors thereof that are tolerant to one or more stress conditions. In particular, the invention relates to methods for producing seeds and/or vegetative propagules that have an enhanced ability to survive, grow and/or produce harvestable products when placed under one or more sub-optimal growing conditions (stresses) that in ‘parental’ plants and untreated lineages cause a significant drop in growth, survivorship, biomass, seed production and/or harvestable yield (for crops).
[0061] The methods used in the invention and detailed examples of the invention are set out below.
[0062] Within this specification, embodiments have been described in a way that enables a clear and concise specification to be written, but it is intended and will be appreciated that embodiments may be variously combined or separated without parting from the invention.
[0063] Within this specification, the terms “comprises” and “comprising” are interpreted to mean “includes, among other things”. These terms are not intended to be construed as “consists of only”.
[0064] Within this specification, the term “about” means plus or minus 20%, more preferably plus or minus 10%, even more preferably plus or minus 5%, most preferably plus or minus 2%.
[0065] Within this specification, the term “homolog” may mean a gene related to a second gene by descent from a common ancestral DNA sequence. The term may mean a gene similar in structure and evolutionary origin to a gene in another species.
[0066] Within this specification, the term “propagule” means any plant material which can be used for the purpose of plant propagation. In asexual reproduction, a propagule may be a woody, semi-hardwood, or softwood cutting, leaf section, or any number of other plant parts. In sexual reproduction, a propagule is a seed or spore. In micropropagation, a type of asexual reproduction, any part of the plant may be used, though it is usually a highly meristematic part such as root and stem ends or buds.
[0067] Within this specification, the term “vegetative propagule” means offspring which is the clonal (i.e. genetically identical) descendant of a single parental plant derived via plant materials other than a biological seed. This is in contrast to seed which is usually the result of sexual reproduction, i.e. the decendant of two or more parental plants.
[0068] Within this specification, the term “tolerant” means that the offspring/vegetative propagule(s) show an increased tolerance to one or more stresses than do the parental plant(s). It is preferred that this increase is statistically significant.
Example 1
Inherited Response to Low Humidity Stress in Arabidopsis Offspring
[0069] It has been found that Arabidopsis plants exposed to one form of water stress (low relative humidity LRH), respond in the short term by reducing the number of stomata (pores) in the leaves so that they do not lose excessive amounts of water and survive. The resultant plants are small but do nevertheless survive to set some seeds. Quite remarkably, however, seeds collected from these plants perform better when placed in identical conditions. The plants are also larger and produce far more seed. The plants used are so inbred that the offspring are to all intents and purposes genetically identical to the parent. Thus, it has remarkably been shown that stressing the parent plant pre-adapts the offspring to the same stress in the next generation. A similar phenomenon has been seen with other stresses (i.e. cold and heat stress (Whittle et al, 2009), UV-C light (Molinier et al, 2006), and pathogens such as bacteria (Molinier et al, 2006). The invention described herein is particularly applicable to commercial seed production in crops. Moreover, growing the parental clones/populations used to produce commercial seed lots under appropriate stressed conditions should pre-programme the epigenetic profiles of the seeds to increase the potential for adaptation to the same stresses when germinated. Importantly, such effects do not persist over many generations and rapidly fade. Thus, the present invention provides a means of improving plant production without changing the genetic code.
[0070] The density and operation (opening) of stomatal pores on the surface of leaves are both heavily influenced by environmental cues; together they control stomatal conductance of the leaf to water vapour (g s ) over short (minute to hour) and long (seasonal to lifetime) timescales. Such plasticity allows the plant to balance the conflicting needs to capture atmospheric carbon dioxide (CO 2 ) for photosynthesis and to minimise water loss through transpiration and water use efficiency (wue) is inversely correlated with leaf stomatal density over a plant's lifetime. There have been recent advances in our understanding of the genetic regulation of stomatal development. A pathway governing stomatal guard cell development involves a “default” fate of protoderm epidermal cells to form stomata but expression of a series of patterning genes blocks entry into the stomatal lineage (and so guard cell formation) and consequently sets stomatal density. Positive regulators determine entry into the stomatal lineage and asymmetric divisions forming stomatal guard cells. Mechanisms allowing plants to maintain plasticity for water conservation and carbon fixation in response to the environmental cues they receive are less clear. The possibility that plastic responses to environmental stress experienced early in the life of the plant could provide adaptive conditioning in anticipation for similar stresses later in development or even in the seminal generation was investigated.
[0071] The response of the stomatal pathway to different levels of ambient humidity was analysed. Arabidopsis thaliana ecotypes Landsberg erecta and Columbia were grown under constant low relative humidity (LRH; 45%±5) or under experimental control (65%±5) humidity from seed to seed harvest. Stomatal frequency (index of stomata as a percentage of epidermal cells (SI)) was influenced by LRH stress ( FIG. 1 ). In the Landsberg erecta ecotype, it was reduced in each repeated experiment with a large effect each time (Cohen's d-test >0.80) and wue increased. In isogenic progeny of the LRH-treated parent, however, SI was no longer reduced when progeny were exposed to the same LRH stress (LRH-LRH) ( FIG. 1 ). Wue was no longer correlated with SI and increased. Likewise, fitness (measured as the parameters biomass and seed number) was reduced by LRH stress in the first exposed generation but not in LRH-LRH plants ( FIG. 2 ). When stressed plants were returned to control RH during development (LRH→control) SI still decreased (25% decrease, P=0.028), and when stressed plants were crossed with control plants (LRHxcontrol) SI was increased under LRH stress (LRHxcontrol-LRH) compared with crosses from control plants (Controlxcontrol-LRH) (40% increase, P=<0.01). All sample plants were affected similarly.
[0072] DNA methylation of loci for genes in the stomata pathway was investigated to see whether it was imposed differentially with environment. Differences in DNA methylation were screened for under LRH compared with the control environment in 11 stomata patterning and formation genes (Table 1). Differential methylation associated with RH treatment was found in both regulatory and 5′ coding regions of the SPEECHLESS(SPCH) and FAMA genes ( FIG. 1 ). SPCH and FAMA genes are paralogues encoding for basic-Helix Loop Helix (bHLH) proteins that are putative transcription factors. Expression of these genes, in a pathway with MUTE and their dimerization partners ICE1 and SCREAM2, regulates the entry of protoderm cells into the stomatal lineage and controls subsequent asymmetric and amplifying cell divisions culminating in the formation of stomatal guard cells. SPCH is required to initiate asymmetric cell divisions forming meristemoids and FAMA regulates the final division of the guard mother cell. SPCH and FAMA were significantly more methylated from leaves exposed to LRH. Methylation at the 5′ region of transcription factor genes is rare in the Arabidopsis genome and may be caused by or cause aberrant expression. Expression of both genes was suppressed under LRH conditions. Gene expression was suppressed (by 31-58%) ( FIG. 1 ) when DNA was methylated under LRH and correlated with reduction in stomatal number on the leaf epidermis.
[0000]
TABLE 1
Primer designs for bisulfite-specific PCR of genes in the stomata
pathway. ER, ERL1 and ERL2 were also tested in the Col-0 ecotype.
Gene
GenBank
Primer
name
accession no.
name
DNA sequence (5′-3′)
ER
At2g26330
ERF
GAAATAAGTTATAGAGAGATAAAGATT (SEQ ID NO: 1)
ER
At2g26330
ERR
AAAAAAATAAAATAAATAAAAAAAA (SEQ ID NO: 2)
ERL1
At5g62230
ERL1F
AAATTTATAGGGAAAGTTTTGATGG (SEQ ID NO: 3)
ERL1
At5g62230
ERL1R
TCAAATAAAATTCTTACAAAAAAACAAC (SEQ ID NO: 4)
ERL1
At5g62230
ERL1FD
TTTRRTTTTTTTGTGTTTTGGTTT (SEQ ID NO: 5)
ERL1
At5g62230
ERL1RD
TTTGGAAGCAAYAAGTATYGGCTT (SEQ ID NO: 6)
ERL2
At5g07180
ERL2F
TGGATATATTGATTTAGAGTATGTT (SEQ ID NO: 7)
ERL2
At5g07180
ERL2R
ATACCATTTAATACAAATTAACCTC (SEQ ID NO: 8)
ERL2
At5g07180
ERL2FD
TTTGTTTGAATTTRRTTTTTT (SEQ ID NO: 9)
ERL2
At5g07180
ERL2RD
TGCAAGCAAIAAIAAGTAAIITIT (SEQ ID NO: 10)
FAMA
At3g24140
FAMAF
TAAATTTTTTAGGTGAATTTTTAGG (SEQ ID NO: 11)
FAMA
At3g24140
FAMAR
TATCAAAAAATATTACTCCAAATCC (SEQ ID NO: 12)
FAMA
At3g24140
FAMA2F
TTTTTTTTATTATTTTGTATGTTTTG (SEQ ID NO: 13)
FAMA
At3g24140
FAMA2R
AAATTCACCTAAAAAATTTAATACC (SEQ ID NO: 14)
FAMA
At3g24140
FAMAFp
TTTTTAAAAAATTGATTATT (SEQ ID NO: 15)
FAMA
At3g24140
FAMARp
AATTGCATGCTTTTTTTTTAA (SEQ ID NO: 16)
FAMA
At3g24140
FAMAFD
TTGTATGTTTTGCRTTTTTTATA (SEQ ID NO: 17)
FAMA
At3g24140
FAMARD
ATGCATGGCTYATTAGAAATA (SEQ ID NO: 18)
FAMA
At3g24140
FAMAFpr
TTTTATTTTTAAAAGTAATTATAATGATTA (SEQ ID NO: 19)
FAMA
At3g24140
FAMARpr
AAATCTTAACAAAATCCAAAACCAA (SEQ ID NO: 20)
ICE1
At3g26744.1
ICE1F
TGAGAGATTATTTTGTTTTTTTTTTA (SEQ ID NO: 21)
ICE1
At3g26744.1
ICE1R
AAATTTTTAATTTTTTAATTGAG (SEQ ID NO: 22)
MUTE
At3g06120
MUTEFpr
AAAATTATAAATAGAAGTGTTATTTAAGTG (SEQ ID NO: 23)
MUTE
At3g06120
MUTERpr
AAATTCAATTATTCAACTACCTAAAC (SEQID NO: 24)
SCRM2
At1g12860
SCRMF
AAGTTTTTTTTAAAATAATGGAGAT (SEQ ID NO: 25)
SCRM2
At1g12860
SCRMR
AAAAATAAAAAACAAAATAAAAACC (SEQ ID NO: 26)
SDD1
At1g04110
SDD1F
TTTGTAATTTGTGTAGTTGGTAATAA (SEQ ID NO: 27)
SDD1
At1g04110
SDD1R
ATAACTCTCCATAAAAAAACTTTCC (SEQ ID NO: 28)
SPCH
At5g53210
SPCHF
TTAATTTTTGGAAGTTAAGAAATAA (SEQ ID NO: 29)
SPCH
At5g53210
SPCHR
CAACTAACCAATAAACTATAAAAAC (SEQ ID NO: 30)
SPCH
At5g53210
SPCHFp
TTATTTTAGAGAGTTTTGAAGGTGT (SEQ ID NO: 31)
SPCH
At5g53210
SPCHRp
ATTACCCATCTTACTTATTATCTTCTTCTA (SEQ ID NO: 32)
SPCH
At5g53210
SPCHFpr
TTAATTTTTTATGGATAGGATTTAA (SEQ ID NO: 33)
SPCH
At5g53210
SPCHRpr
AACACTATTAAACCTAAAAACTTTAACTAA (SEQ ID NO: 34)
TMM
At1g80080
TMMF
TTTGATTTGTATAAAAATTATTTTAA (SEQ ID NO: 35)
TMM
At1g80080
TMMR
AAAATAAAACCAATAACTCTATTTC (SEQ ID NO: 36)
TMM
At1g80080
TMMFD
TTIAIAIAAIAAIAAIAAITAAGA (SEQ ID NO: 37)
TMM
At1g80080
TMMRD
TATGTGARCTAGGRCATGGTA (SEQ ID NO: 38)
YDA
At1g63700
YDAF
TGAAGGTATAGGATTAAGTAGAAGTT (SEQ ID NO: 39)
YDA
At1g63700
YDAR
ATTATCCCAAAATACATAAAAAAAA (SEQ ID NO: 40)
YDA
At1g63700
YDAFD
TTAYTTTGTAATGTTGAAYAA (SEQ ID NO: 41)
YDA
At1g63700
YDARD
TTTTGTATTARAARAARGGTGTTT (SEQ ID NO: 42)
[0073] The role of methylation in regulating stomatal frequency was further investigated using methyltransferase mutants. In the mutant for the maintenance cytosine methyltransferase MET1 (Decreased Methylation 2DNA) (met1)) SI was increased in LRH and differential methylation with treatment was reduced for both SPCH and FAMA. Expression of SPCH was no longer reduced by LRH treatment and FAMA expression increased ( FIG. 1 ). In the double mutant for Domains Rearranged Methyltransferases 1 and 2 (drm1/drm2) SI was not reduced by LRH, nor was expression of FAMA, SPCH expression increased and no differential methylation was detected with treatment ( FIG. 1 ). DOMAINS REARRANGED METHYLTRANSFERASE 2 (DRM2) is the only enzyme so far known to methylate DNA de novo in Arabidopsis . De novo methylation of SPCH and FAMA occurred in response to LRH stress. Single base-resolution sequences of fragments of the SPCH and FAMA gene loci showed differential methylation with treatment in both symmetric (CG) and asymmetric (CHH where H is any base) contexts ( FIG. 1 ). Additional asymmetric methylation under LRH in the wild type (WT) was not imposed in the drm1/2 plants at either gene locus ( FIG. 1 ). Non-CG methylation is maintained redundantly by DRM2 and the protein CHROMOMETHYLASE 3 (CMT3). We also examined the response of the cmt3 mutant and found that it responded to LRH in the same manner as the WT plants, with reduced SI, reduced expression and increased methylation in LRH (data not shown). LRH-induced asymmetric methylation of FAMA was abolished in the cmt3 plants. These differences between the two genes implied that de novo establishment of asymmetric methylation was required for the response in FAMA but that CG-dependent maintenance of induced methylation might be equally important for the differential environmental response of SPCH.
[0074] DRM2-mediated transcriptional gene silencing (TGS) by uni-directional methylation of gene promoter sequences in Arabidopsis is directed by 24 nt short-interfering RNAs (siRNAs): Post-transcriptional gene silencing (PTGS) by 21-22 nt secondary siRNAs has also been associated with bi-directional methylation of transcribed regions. A range of mutants for RNA-directed DNA methylation (RdDM) was grown in the control and LRH environments to investigate the role of siRNA direction in the observed DNA methylation and physiological responses. In TGS, RDR2 (ma dependent rna polymerase 2) is required for the synthesis of double-stranded short RNAs. Both maintenance and transitivity of PTGS require RDR6 and depend on transcription of the target gene. Dicer-like RNA III proteins process dsRNA or hairpin RNAs with DCL3 primarily acting on RDR2-produced RNAs and DCL4 on RDR6-produced RNAs; there is, however, some overlap and compensatory processing by the four Arabidopsis DCLs in single dcl mutants. No true rdr2 or dcl3 mutants germinated under LRH stress; both genes were expressed (data not shown), total small RNA content was increased compared with the WT and 24 nt siRNAs were present in seedlings although at much reduced levels ( FIG. 3 ). In the control treatment, intriguingly, stomatal frequency of both the rdr2 and dcl3 mutants (compared with their background ecotype Columbia) was higher (data not shown), suggesting that siRNAs may be required to suppress the formation of stomata at some point in the pathway. Both SPCH and FAMA remained comparatively unmethylated at asymmetric bases in rdr2, as in drm1/2, ( FIG. 1 ) and expression of FAMA was increased confirming previous observations. 21 nt siRNAs were present in dcl4 plants in both treatments but not at measurable levels in rdr6 (data not shown). LRH-induced methylation was reduced overall in rdr6 but not abolished in either symmetrical or asymmetrical contexts in SPCH or FAMA ( FIG. 1 ). Expression of both SPCH and FAMA increased in rdr6 ( FIG. 1 , confirming previous results) and SI increased both in the WT control and under LRH. These data showed that both SPCH and FAMA were targets of RdDM under environmental stress and implied that both loci could be subject to TGS and PTGS.
[0075] Small RNA reads from high-throughput sequencing data of A. thaliana show seven small RNAs located within 300 bp upstream of the FAMA gene (accessed in TAIR 9 http://gbrowse.arabidopsis.org). Expression of these small RNAs was quantitatively assayed together with FAMA and surprisingly, given the increased expression of FAMA in rdr2 plants, was positively correlated with expression of FAMA (P=0.014, R 2 0.97). Upstream of SPCH (and a predited 177 bp gene At5g53205 for an unknown protein) is a cluster of rolling-curve-type helitron family transposons corresponding with 42 small RNAs and a 40 bp tandem repeat within a 427 bp dispersed repeat region. Small transposons like these are believed to be preferentially dependent on RdDM via DRM1/2 for silencing. It was hypothesised whether these small RNAs could direct non-CG methylation that spread beyond the transposable elements (TEs) to affect transcription of SPCH as has been shown for the seven tandem repeats of the F-box protein encoded by SUPPRESSOR OF drm1 drm2 cmt3 (SDC) and for RdDM arising from tandem direct repeats around the transcription start site of FWA. Expression of SPCH was measured together with expression of a subset of these siRNAs. It was found that it was inversely correlated (P=0.004, R 2 0.87) so that SPCH was downregulated when expression of these siRNAs was upregulated and SPCH was methylated in LRH. On exposure to LRH stress, 24 nt siRNAs corresponding the TEs upstream of the SPCH locus were induced and assayed DNA methylation spread into the regulatory and genic regions of SPCH.
[0076] Methylation of SPCH and FAMA in isogenic progeny from single parents exposed to LRH was next examined to see whether it correlated with gene expression and SI. LRH-control progeny retained parental methylated status ( FIG. 1 ) in the coding and non-coding regions for SPCH and exhibited similarly suppressed expression. It was therefore concluded that methylation of the SPCH locus was heritable. Conversely, the methylated status of SPCH was lost in LRH-LRH progeny, such that this gene became both unmethylated and hyper-expressed ( FIG. 1 ). Drm1/2 progeny (LRH-control) remained unmethylated (Table 2). Unlike the WT, cmt3 LRH-control progeny were not methylated at SPCH, but methylation was induced by LRH regardless of parentage (cmt3 LRH-LRH and cmt3 control-LRH plants).
[0077] There are several plausible causes for the loss of methylation at SPCH in LRH-LRH plants, including loss of RdDM. In equal quantities of total RNA from progenies, the entire complement of small RNA duplexes was reduced in LRH-LRH plants ( FIG. 3 ) and expression of the upstream siRNAs for SPCH was reduced ( FIG. 3 ). This implied that heritable retention of LRH-induced methylation influenced RdDM so that it could not proceed under a repeated stress, consistent with the inability of cmt3 plants to transmit methylation to their progeny. As transgenerational DNA methylation and siRNAs were not lost in the control environment, the subsequent imposition of LRH stress must have been the causative factor rather than genomic re-setting and reactivation of methylation during the parental reproductive phase.
[0000]
TABLE 2
Methytlated regions (in numbers of base pairs) of methyltransferase mutants in
control and low relative humidity (LRH) in and around the SPCH locus. ✓ indicates
positive amplification by real-time PCR of the methylated portion of genomic
DNA from each sample in comparison with the unmethylated portion.
547
48
1.403
220
469
176
1.261
51
700
200
Chr5: 21589259←
bp
bp
kb
bp
bp
bp
kb
bp
bp
bp
Control.met1
—
—
—
—
—
—
—
—
—
✓
LRH.met1
—
—
—
✓
—
✓
—
—
—
—
Control-control.met1
—
—
—
—
—
—
—
—
—
✓
LRH-control.met1
—
—
—
✓
—
—
—
—
—
✓
Control-LRH.met1
—
—
—
✓
—
✓
—
—
—
—
LRH-LRH.met1
—
—
—
—
—
—
—
—
—
✓
Control.drm1/2
—
—
—
—
—
—
—
—
—
—
LRH.drm1/2
—
—
—
—
—
—
—
—
—
—
Control-control.drm1/2
—
—
—
—
—
—
—
—
—
—
LRH-control.drm1/2
—
—
—
—
—
—
—
—
—
—
Control-LRH.drm1/2
—
—
—
—
—
—
—
—
—
—
LRH-LRH.drm1/2
—
—
—
—
—
—
—
—
—
—
Control.cmt3
—
—
—
✓
—
—
—
—
—
—
LRH.cmt3
✓
—
✓
✓
✓
✓
✓
—
✓
✓
Control-control.cmt3
—
—
—
✓
—
—
—
—
—
—
LRH-control.cmt3
—
—
—
✓
—
—
—
—
—
—
Control-LRH.cmt3
✓
—
✓
✓
✓
✓
✓
—
✓
✓
LRH-LRH.cmt3
✓
—
✓
✓
✓
✓
✓
—
✓
✓
[0078] Here, loss of siRNAs could trigger active demethylation. Loss of inherited methylation at SPCH in LRH-LRH plants and in the cmt3 mutants (LRH-control) was apparent at symmetric sequences ( FIG. 1 ). Evidence from successive generations of met1 suggests that maintenance of methylated CGs is required for the expression of Arabidopsis cytosine demethylases and that demethylated CGs are subsequently protected from de novo remethylation involving DRM2. In the whole seedlings, transcripts of the demethylating DNA glycosylase REPRESSOR OF SILENCING 1 (ROS1) were abolished by LRH in WT plants and were not detectable in LRH-LRH plants, where CG methylation of SPCH had been abolished, but were expressed in transgenerationally methylated progeny (0.43× control, P=<0.001). Expression of the demethylase DEMETER (DME) was likewise abolished by LRH in WT plants and reduced in methylated progeny of LRH parents (0.74× control) but greatly increased in LRH-LRH (50.3× control). Expression of both demethylases was undetectable in met1 control plants but was increased in met1 by LRH treatment relative to the WT (ROS 1 10.3× and DME 5.7× control). These data suggest a role for demethylation in orchestrating dynamic patterns of CG methylation in response to stress. LRH induces CG methylation but, where this is not replicated and maintained, demethylase is induced perhaps in order to protect against stochastic, de novo genome-wide asymmetric methylation and increased phenotypic abnormalities. At the SPCH locus, loss of CG methylation did not cause an increase in asymmetric methylation ( FIG. 1 ) but there was a decrease in siRNA transcripts associated with loss of methylated CG in SPCH, as has been shown previously for the FWA locus in met1. DME is responsible for the active demethylation of maternal alleles in Arabidopsis imprinted genes and, in developing seed, its expression in the central cell causes differential methylation in the embryo and endosperm genomes. DME-mediated differential tissue demethylation during seed development is associated with activation and suppression of TEs (including a helitron TE remnant), differential siRNA accumulation and distribution, and methylation of genes in close proximity. The findings presented herein strongly suggest a similar mechanism operates on inherited methylation at the SPCH locus in stomatal precursor cells. It is not possible to rule out that ROS1 was also involved in active demethylation of transgenerational, methylated CG at an early stage, which could explain why it was undetectable in LRH-LRH seedlings when SPCH was already demethylated. It is noted, however, that ROS 1 may be less suitable than other DME-family enzymes for this type of rapid, processive demethylation. As rdr2 and dcl3 mutants do not germinate in LRH, it is likely that TE-associated siRNA accumulation and subsequent RdDM is required for correct development of the seed under stress.
[0079] Heritable methylation of SPCH was lost in progeny of transgenerationally methylated parents (LRH-control-control) ( FIG. 1 ) and regained under LRH stress in progeny of demethylated parents (LRH-LRH-control) ( FIG. 1 ). Predictability of the entire target SPCH gene fragment (differentially methylated in first generation plants) remained high through three generations (85%, 95% and 80% respectively). The methylation status of one symmetric site downstream of a sequence repeat at the transcription start site of SPCH explained with high fidelity the observed treatment*parent methylation pattern of the gene and its expression. The repeat sequence itself was hypomethylated in all sample plants regardless of parentage or treatment ( FIG. 1 ). The CpG was invariably unmethylated in control plants, methylated in LRH and transgenerationally methylated in LRH-control progeny in all examined samples and amplicons ( FIG. 1 ). At this base, predictability of demethylation in LRH-LRH was reduced to 71% and of loss and gain of methylation in the third generation reduced further to 55% in LRH-control-control and 43% in LRH-LRH-control. The decreasing predictability of intergenerational LRH-induced methylation at this site was therefore associated with the process of demethylation. It is likely that the process of demethylating and re-establishing methylation under stress following its inheritance at SPCH causes cohorts of nuclei at different stages that, therefore, have different methylation status at reproduction (mitotic and meiotic). An alternative explanation is that cytosines are protected from re-methylation following demethylation, as has been proposed previously, but that this protection is imperfect.
[0080] In contrast with SPCH, in FAMA the differential methylation pattern exhibited by parental plants was replicated in the progenies so that FAMA was methylated in all LRH plants ( FIG. 1 ). There was evidence for inherited methylation of FAMA in a small minority (5%) of the LRH-control offspring but this was less predictable. Differential methylation of FAMA was primarily determined by growing conditions experienced by plants during development and, unlike at SPCH, was only weakly heritable. Genic CG methylation was present in LRH-LRH, relieved in LRH-control plants relative to first generation WT controls and absent in rdr6 (but not rdr2) ( FIG. 1 ). This methylation may have been the hallmark of an older PTGS event that, unusually, was released during meiosis. Assayed siRNAs were still present in LRH-control offspring and positively correlated with FAMA expression (P=0.035, R 2 =0.80) except for transcripts of the genic 21 nt siRNA which were now inversely correlated with FAMA mRNA (P=0.006, R 2 0.98). The experiments suggest that stress-inducible RdDM followed by meiosis may play a role in this release of genic methylation. As in tobacco, presence of PTGS-derived genic methylation did not affect FAMA expression and nor did its release. In all treatment*parent conditions, FAMA expression was highly correlated with expression of SPCH and final SI. This can be explained by interaction between FAMA and other genes upstream in the stomatal pathway which drive subsequent divisions in a dosage-dependent manner including the ICE1.SCRM2 heterodimer partners of SPCH and FAMA and SPCH itself. Increased expression of FAMA in LRH-LRH plants may have been driven largely by increased expression of SPCH, rather than by de novo methylation of FAMA, consistent with the derepression of SPCH after loss of CG methylation and the decrease in the siRNA complement. Two stress-associated kinases (MKK7 and MKK9) in the mitogen-activated protein kinase signalling cascade that interacts with the SPCH→FAMA stomatal development pathway have also been shown to have opposite effects dependent on whether they are driven by the SPCH promoter at the lineage-defining stage or by the FAMA promoter in guard mother cells. Usual inhibitors of stomatal development can be induced to promote stomata-forming divisions. The data presented herein provides evidence that, once committed to the stomatal lineage at SPCH, in planta, the majority of meristemoids will form functional guard cells and this is because of co-ordinated expression of, at least, SPCH and FAMA. Although g s of LRH-LRH plants was reduced when SI was increased, no more aberrant stomatal tumours, malformed precursors or clusters of stomata were noted in these plants than in the WT. SPCH additionally regulates expression of several genes in the stomatal patterning pathway and is the substrate for phosphorylation by MPK3 and MPK6 at the end of the YDA-directed MAPK signalling cascade. SPCH therefore appears to be an important hub for co-ordinating developmental and environmental cues that is itself responsive to environmental stress through RdDM.
[0081] It is proposed that the subtle interplay of both de novo and inherited methylation and demethylation at SPCH effectively “immunised” the progeny against the same stress on stomatal development experienced by their parents. This can be explained as a transgenerational “adaptive imprinting” response that is mediated by targeted DNA methylation.
[0082] LRH-LRH and LRH-control progenies apparently benefited in terms of increased biomass and seed production ( FIG. 2 ). Fitness profiles of these progenies were altered according to the experience of their parents. A. thaliana is a self-fertilizing, annual species that will typically harbour very little genetic variation within its populations when compared with inter-populational variation. Locally, populations must therefore rely heavily on plastic resilience to accommodate fluctuations in growing conditions. Viewed in this context, an ability to moderate default physiological responses in the light of parental experiences could have considerable advantages for inbred populations to mitigate the absence of local genetic variability. It is expected to apply most strongly amongst inbreeding or apomictic perennials, where individuals suffer recurrent exposure to environmental fluctuations over many seasons.
Methods—Summary
[0083] Supplied Arabidopsis thaliana (L.) Heynh Landsberg erecta seeds were grown in low (45%) and control (65%) relative humidity (RH) growth chambers and seed collected. Collected seeds from individual parents in both treatments were grown in low and control RH alongside untreated seeds and supplied seeds for several known methyltransferase mutants. This experiment was repeated four times; supplied seeds for known RNAi mutants were grown in the fourth repeated experiment. Each time, stomatal density (stomata mm −2 ) and index (percentage of epidermal cells forming stomata) were assessed at the same stage of growth by microscopic examination of impressions of the abaxial leaf surface. Plant dry weight, seed weight and seed number were assessed following senescence. Differential methylation with treatment and parentage was screened by high resolution melt (HRM) analysis of PCR products from known genes in the stomatal formation pathway, following bisulfite conversion of sample DNA. Full lengths and upstream of target genes were analysed for differential methylation by capturing the methylated portion of the sample genome and performing qPCR of resulting DNA for 300 bp fragments of the genes of interest. Single base-resolution methylation profiles were confirmed by bisulfite sequencing of ≧32 cloned PCR fragments for target gene regions studied. SPCH and FAMA expression levels were measured in seedling RNA by multiplexed-tandem qPCR (MT-qPCR). MT-qPCR data were analysed in comparison with housekeeping genes of equal efficiencies to target genes by two standard curve analysis. Multiple siRNAs expression was analysed by in solution hybridization and RNase digestion of the enriched small RNA fraction with custom synthesized probes, followed by electrophoretic separation and quantification of the protected probes.
Methods—Plants and Growth Environment.
[0084] Seeds of Arabidopsis thaliana (L.) Heynh. ecotypes Landsberg erecta (Ler ref. NW20) and Columbia (Col-0 ref. N1092), methyltransferase mutants for MET1 ((Decreased Methylation 2DNA, met1 ref. N854300), Chromomethylase (cmt3 ref. N6365) and Domains rearranged methyltransferase 1/2 (drm1/drm2 ref. N6366) and for RNAi mutants RNA dependent rna polymerase 2 (rdr2 ref. N850602), RNA dependent rna polymerase 6 (rdr6 ref. N24285), Dicer-like 3 (dcl3 ref. N505512) and Dicer-like 4 (dc14 ref N6954) were supplied by NASC (Nottingham, UK). Seeds were sown in seedling compost (Sinclair, Lincoln, U.K.), germinated and grown in controlled environment growth cabinets (Saxcil, R. K. Saxton, Bredbury, Cheshire, U.K.) until harvest, according to ARBC guidelines except that the relative humidity of one cabinet was controlled at 45%±5 whilst the other was maintained at 65%±5. After 64 d, stage 9.70, seeds were harvested from each individual. Harvested Ler seeds, supplied Ler seeds (as before) and supplied seeds for mutants (as before) were sown, germinated and grown as before except that growth cabinets were swapped and no stratification was applied. Different (rotated) growth chambers were used in each of the 4 repeated experiments to accommodate for growth chamber effects (Sanyo Gallenkamp, Loughborough, U.K.). The complete dry biomass and seed mass of individual harvested plants were weighed and seeds counted, following threshing through a series of graded meshes, by capturing a digital image of collected seeds using an Epson Perfection 3170 scanner (Epson (U.K.), Hemel Hempstead, U.K.) then particle analysis using ImageJ software version 1.37 (freeware NIH, USA).
Methods—Stomatal Analyses
[0085] Stomatal density (stomata mm −2 ) and index (percentage of epidermal cells forming stomata) were determined by making impressions of the entire abaxial surface of one mature rosette leaf (insertion 6-8, length approximately 40 mm) and one cauline leaf (insertion 13-15, length approximately 15 mm) from 48 plants (each of 16 replicate plants from each of 3 individual parents in the treatment*parent experiments) at the same physiological stage (6.50) in each repeated experiment. Digital images were then captured from an Axioscope 2 microscope with an Axiocam camera attached (Carl Zeiss Ltd), using Axio Vision 3.1 (Image Associates, Oxfordshire, UK) software and the number of stomata and other epidermal cells per unit area counted using ImageJ software (as before). Gas exchange (stomatal conductance to water vapour and instantaneous leaf-level water use efficiency) was measured using the Lc pro+ infra-red gas analyzer with Arabidopsis leaf chamber (ADC BioScientific, Great Amwell, U.K.) in 6 replicate plants pre-conditioned in ambient RH in the dark for 12 hr.
Methods—DNA Methylation Analyses
[0086] Whole seedlings (first true leaf stage), mature and immature leaves from ≧12 replicate plants were snap frozen in liquid nitrogen and stored at −80° C. DNA was extracted using the Dneasy plant mini-kit (Qiagen, U.K.) according to the manufacturer's instructions. 2 μg genomic DNA was then modified by bisulfite treatment using the EZ DNA methylation kit (Zymo Research, Orange, Calif.) according to the manufacturer's instructions. Desulphonated DNA was diluted 1 in 5. High resolution melt (HRM) analysis was used to analyse differential methylation with treatment as in Wojdacz, T. K. & Dobrovic, A. Methylation-sensitive high resolution melting (MS-HRM): a new approach for sensitive and high-throughput assessment of methylation. Nucleic Acids Res. 35, No. 6 e41 (the content of which is incorporated herein by reference in its entirety) except that each 20 μl reaction mix contained 1× Biomix (Bioline, London, U.K.), 25 μM Syto9 dye (Invitrogen, Carlsbad, Calif.) and 300 nM each forward and reverse bisulfite-specific primer for the gene of interest. PCR amplification conditions used were: 2 min at 95° C., then 50 cycles of 95° C. for 15 s and 50° C. for 30s, 60° C. hold for 1 min and HRM from 58-80° C. at 0.5° C. s −1 . For each gene, untreated genomic DNA (diluted 1 in 1000) was included as a positive control using the equivalent (but not bisulfite-specific) primer. Differential methylation with treatment was identified using the RotorGene™ 6000 Series Software version 1.7 (Corbett Research UK Ltd., Cambs., U.K.) at an 80% confidence level. Assays were repeated 6-8 times for genes putatively identified as differentially methylated.
[0087] Positive results indicating differential methylation in the SPCH and FAMA genes were validated by capturing the methylated portion of genomic DNA using the Methylamp Methylated DNA Capture kit (Epigentek, Cambridge Bioscience, Cambridge, U.K.) and performing comparative qPCR analysis using negative controls provided in the kit (Ig mouse antibody). Subsequently, primers were designed to target every 300 bp of the coding regions, for 600 bp of (5′) upstream regions of the SPCH and FAMA genes and for the 2.3 kb upstream genomic region of SPCH. qPCR and HRM conditions were as described above except that 15 ng of template DNA were used, T a was 56° C. and an extension phase of 66° C. for 6 min replaced the 1 min hold; HRM was from 68-90° C.
[0088] Base-pair resolution methylation profiles were obtained by sequencing ≧32 cloned amplicons (vector pCR2.1; Invitrogen, Carlsbad, Calif.) per sample of three, pooled replicate plants (Geneservice, Source Bioscience PLC, Nottingham, U.K.) following bisulfite treatment and PCR, as described above except that 5 nM labelled, synthetic DNA with methylated and unmethylated cytosines for each PCR product (Sigma-Aldrich Ltd., Gillingham, U.K.) was added to the 2 μg sample DNA prior to bisulfite treatment as a positive control for complete bisulfite conversion. Differential methylation was assessed with reference to the unmodified genomic DNA sequence and comparison of cytosine to thymine conversion between treatments. Sequences were aligned using ClustalW2 and predictability calculated as the inverse of entropy using BioEdit v. 7.0.9.0.
[0089] Following each round of FIRM, qPCR and PCR, a sample of products was analysed for size accuracy and purity using the Agilent Bioanalyzer Series II DNA 1000 chip (Agilent, Winnersh, U.K.).
Methods—RNA Expression Analyses
[0090] Total RNA was isolated from frozen leaf material using the RNeasy Plant Mini kit (Qiagen, U.K.) according to the manufacturer's instructions. Primers for Multiplexed Tandem PCR (MT-PCR) were designed for the target genes SPCH and FAMA and for the internal control genes PP2A and SAND. MT-PCR was performed as in Stanley, K.K. & Szewczuk, E. Multiplexed tandem PCR: gene profiling from small amounts of RNA using SYBR green detection. Nucleic Acids Res. 33, 20 e180 (2005) (the content of which is incorporated herein by reference in its entirety) using 500 ng starting RNA, except that Sensimix (Quantace, London, U.K.) reverse transcriptase and buffer were used, and reverse transcription was executed at 45° C. for 15 min followed by 70° C. for 15 min. First round multiplexed amplification was carried out in the ABI9700 thermal cycler using Sybr Premix Ex Taq polymerase (Takara Bio Europe, Saint-Germain-en-Laye, France) and final volumes of 200 nM for each primer. PCR was performed under the following conditions: 1 min at 95° C., 10-15 cycles of 95° C. for 15 s, 58° C. for 20 s and 72° C. for 15 s then 72° C. for 7 min. Pre-amplification products were diluted 1:1 and second-round PCRs prepared with Sybr Premix Ex Taq (as before) and internal primers and 1 μA template cDNA. qPCR was carried out in the RotorGene™ 6000 thermal cycler (Corbett Research UK Ltd., Cambs., U.K.) using the following conditions: 95° C. for 1 min, then 40 cycles of 95° C. for 10 s, 60° C. for 20 s and 72° C. for 8 s and HRM from 70-96° C. at 0.5° C. s −1 . All reactions were prepared in triplicate and serial dilutions completed for genes of interest and controls. RotorGene™ 6000 Series software version 1.7 was used to determine gene amplification efficiencies and RNA quantification (as before) employing the two standard curve method.
[0091] Following each round of PCR and qPCR, a sample of products was analysed for size accuracy and purity using the Agilent Bioanalyzer DNA 1000 chip and kit (as before).
[0000] Methods—siRNA Analyses
[0092] Total RNA was isolated from seedling samples using the mirVana miRNA isolation kit (Ambion, Warrington, U.K.) according to the manufacturer's instructions, checked and quantified using the Agilent Bioanalyzer RNA 6000 Nano and Small RNA chips and kits (Agilent, Winnersh, U.K.) against small dsRNA standards (New England Biolabs, Hitchin, U.K.). 200 ng total RNA from each sample was enriched for the small RNA fraction using the isolation kit (as before). Unlabelled antisense RNA probes of differing nt lengths were designed and constructed using the mirVana probe construction kit (Ambion, Warrington, U.K.) for SPCH, FAMA and local smRNAs; <four probes were detected in each reaction using the mirVana detection kit (Ambion, Warrington, U.K.) according to the manufacturer's instructions. Probes were post-labelled and visualised fluorescently using the Agilent Bioanalyzer Small RNA chip (as before) and small dsRNA standards ladder (as before).
Methods—Primer Designs
[0093] Primer designs for DNA methylation, RNA and siRNA analyses are included as Tables 1, and 3-5. All primers were designed using Primer3 software; bisulfate-specific primers were based on the returned, bisulfite-specific sequence from MethPrimer software.
[0000]
TABLE 3
Primers for unmodified genomic DNA (equivalent to bisulfite-specific
region assayed). These primers were also used for qPCR following
capture of methylated DNA.
Gene
GenBank
Primer
name
accession no.
name
DNA sequence (5′-3′)
FAMA
At3g24140
FAMAFu
CAAACTTCTTAGGTGAATCCTCAGG (SEQ ID NO: 43)
FAMA
At3g24140
FAMARu
ATAGTTTTCCACAACGAGGTTTAGG (SEQ ID NO: 44)
FAMA
At3g24140
FAMA2Fu
CTTCTTCTACTATCTTGCATGTCTTG (SEQ ID NO: 45)
FAMA
At3g24140
FAMA2Ru
AAACTTCTTAGGTGAATCCTCAGG (SEQ ID NO: 46)
FAMA
At3324140
FAMAFup
TCTTCAAAAAATTGACCATT (SEQ ID NO: 47)
FAMA
At3g24140
FAMARup
AACTGCATGCTCTCTTTCTAA (SEQ ID NO: 48)
SPCH
At5g53210
SPCHFu
CCAATCTTTGGAAGCCAAGAAACAA (SEQ ID NO: 49)
SPCH
At5g53210
SPCHRu
GTTGACCGGTTACTCGACATTCTCG (SEQ ID NO: 50)
SPCH
At5g53210
SPCHFup
CCATCTTAGAGAGTCTTGAAGGTGC (SEQ ID NO: 51)
SPCH
At5g53210
SPCHRup
CAACGGGTAGAACGAATAATAGAAGAAGAC (SEQ ID NO: 52)
[0000]
TABLE 4
Primers for qPCR of methylated genomic DNA following enzymatic
capture and amplification of DNA for 454 sequencing.
Gene
GenBank
Primer
name
accession no.
name
DNA sequence (5′-3′)
FAMA
At3g24140
FAMAF1
AAAGCAATCGATGCCACAAC (SEQ ID NO: 53)
FAMA
At3g24140
FAMAR1
AGTCCGCAAACTGCATCAC (SEQ ID NO: 54)
FAMA
At3g24140
FAMAF2
CATCACTACCATGGAACAAACC (SEQ ID NO: 55)
FAMA
At3g24140
FAMAR2
CTGTTGGATGGAACTTGCTATG (SEQ ID NO: 56)
FAMA
At3g24140
FAMAF3
GCTCATTATTACGGGAAATGTAA (SEQ ID NO: 57)
FAMA
At3g24140
FAMAR3
CCCGGCCTTCTTCTTGAAA (SEQ ID NO: 58)
FAMA
At3g24140
FAMAF4
GAAACGAGGTTTACGGCAGA (SEQ ID NO: 59)
FAMA
At3g24140
FAMAR4
GGGACCAACAGAAACTTATCAAA SEQ ID NO: 60)
FAMA
At3g24140
FAMAF5
AAAAGATATTGGTGGTTCGATG (SEQ ID NO: 61)
FAMA
At3g24140
FAMAR5
AAGCAAATAATCATAACATCTAAAAGG (SEQ ID NO: 62)
FAMA
At3g24140
FAMAF6
CTCCAAGCATTTGGAAGAGTG (SEQ ID NO: 63)
FAMA
At3g24140
FAMAR6
CCGCTTGTTCAAAACCTACAA (SEQ ID NO: 64)
SPCH
At5g53210
SPCHF1
CCATCTTAGAGAGTCTTGAAGGTGC (SEQ ID NO: 65)
SPCH
At5g53210
SPCHR1
CAACGGGTAGAACGAATAATAGAAGAAGAC (SEQ ID NO: 66)
SPCH
At5g53210
SPCHF2
GTTTCTGGTAGTGCCCGACT (SEQ ID NO: 67)
SPCH
At5g53210
SPCHR2
CATAGATATGCATGATACTTTTGATGT (SEQ ID NO: 68)
SPCH
At5g53210
SPCHF3
TCCAATCTTTGGAAGCCAAG (SEQ ID NO: 69)
SPCH
At5g53210
SPCHR3
GGCTAAGAGGCGGTTTTCTT (SEQ ID NO: 70)
SPCH
At5g53210
SPCHF4
AACCACCACCAGATTCACCA (SEQ ID NO: 71)
SPCH
At5g53210
SPCHR4
GAGTGGTAGTTGCGGTGGAA (SEQ ID NO: 72)
SPCH
At5g53210
SPCHF5
TCATCCTAATTAATTTTCACTGACTTG (SEQ ID NO: 73)
SPCH
At5g53210
SPCHR5
TTCTTCCCCCACCATATATCC (SEQ ID NO: 74)
SPCH
At5g53210
SPCHFmet
CAACTGGCCAATGAGCTGTA (SEQ ID NO: 75)
SPCH
At5g53210
SPCHRmet
AAGTCCTCGAACACCTCAGC (SEQ ID NO: 76)
SPCH
At5g53210
SPCHFumet
AATATTAACACCGTCGACGAAA (SEQ ID NO: 77)
SPCH
At5g53210
SPCHRumet
GCTGAATTTGTTGAGCCAGTT (SEQ ID NO: 78)
SPCH
At5g53210
SPCH6F
GAAGAGCCCCCAAAATCTTC (SEQ ID NO: 79)
SPCH
At5g53210
SPCH6R
TCCCTACTTGATCTCTGATCTTGTT (SEQ ID NO: 80)
SPCH
At5g53210
SPCH7F
TTTTCGTTGGGAGTTTAGTGC (SEQ ID NO: 81)
SPCH
At5g53210
SPCH7R
TGTTGAGCCAGTTCTTCTGC (SEQ ID NO: 82)
SPCH
At5g53210
Up1F
CGCTATACAACGAATCCATGA (SEQ ID NO: 83)
SPCH
At5g53210
Up1R
TCACGGGATGGGTAAAGAAA (SEQ ID NO: 84)
SPCH
At5g53210
Up2F
CTAATGAACGGACGGTTTGC (SEQ ID NO: 85)
SPCH
At5g53210
Up2R
TGGGCTAAAATAATTGGGACA (SEQ ID NO: 86)
SPCH
At5g53210
53205F
TGCGTTAGGACTATCCATTTCA (SEQ ID NO: 87)
SPCH
At5g53210
53205R
ATGCAACATCGAATCATCCA (SEQ ID NO: 88)
SPCH
At5g53210
Up3F
TCCATACTTTCACCCAAAAAGAA (SEQ ID NO: 89)
SPCH
At5g53210
Up3R
TCTTGCAACACAAAATGTTAAGG (SEQ ID NO: 90)
SPCH
At5g53210
Up4F
TTTAAACTCCATATCTTTGCAGAAAAC (SEQ ID NO: 91)
SPCH
At5g53210
Up4R
TTCGTATAAACCTTAACGAGAGAGC (SEQ ID NO: 92)
SPCH
At5g53210
Up1AF
CCCATCCCGTGATTTATTTTT (SEQ ID NO: 93)
SPCH
At5g53210
Up1AR
TTACCCAACCATTTTTGCAC (SEQ ID NO: 94)
SPCH
At5g53210
SPCH1AF
TTTCTCCGGTTACGTTCCAC (SEQ ID NO: 95)
SPCH
At5g53210
SPCH1AR
TCCGACAGCTGCATCTACAC (SEQ ID NO: 96)
[0000]
TABLE 5
Primers for MT-qPCR of stomatal developmental and endogenous control
genes Primers for qPCR of ROS1 and DME were as designed and used by 15 .
Primers for qPCR of RDR2 were RDR2F (5′-GGGTCCAGAGCTTGAGACTG-3′ (SEQ
ID NO: 113)) and RDR2R (5′- CCCTTCTCCAAGGATTGACA-3′(SEQ ID NO: 114)).
Primers for qPCR of DCL3-1 were DCL3F (5′-GTCTTTGAGCCGTTGCTTTC-3′ (SEQ
ID NO: 115)) and DCL3R (5′- GTGAAGCTGCTTTTCCCAAG-3′(SEQ ID NO: 116)).
Primers for genotyping methyltransferase mutants were as in 23-25 , flank-
ing the insertion AAGTGGCACTTCATCGTCTCCCAATCAAAATGAAGCT (SEQ ID NO: 117)
(GenBank accession CC887813) for DRM2. Antisense probes for siRNA analyses
were designed to the small RNA sequences downloaded from the Arabidopsis
Small RNA Project database (http://asrp.cgrb.oregonstate.edu/) 19,36-40 for
the region 3: 8714.3k . . . 8721k for FAMA and 5: 21601k . . . 21611.4k
for SPCH. In this database SPCH is currently located at 5: 21603.8k.
Additional (A) bases were added to artificially create different length
probes The antisense probe for FAMA RNA was CUUCUGCCGUAAACCUCGUUUCACUUGaaaa
(SEQ ID NO: 118) and for SPCH was UUAAGUGCUCGUUCAUUUGCUUUCUCCGaaaa
(SEQ ID NO: 119).
Gene
GenBank.
Primer
name
accession no.
name
DNA sequence (5′-3′)
FAMA
At3g24140
FAMA EF
CAAGTGAAACGAGGTTACGG (SEQ ID NO: 97)
FAMA
At3g24140
FAMA ER
GTACAAAGTTCTCGCCGTGT (SEQ ID NO: 98)
FAMA
At3g24140
FAMA IF
TTTACGGCAGAAGACATAGCAAA (SEQ ID NO: 99)
FAMA
At3g24140
FAMAIR
TCATCACATTGTCAATAGATTGGAG (SEQ ID NO: 100)
SPCH
At5g53210
SPEEC EF
TGGAACGTAACCGGAGAAAG (SEQ ID NO: 101)
SPCH
At5g53210
SPEEC ER
ACGTTGTTTCTTGGCTTCCA (SEQ ID NO: 102)
SPCH
At5g53210
SPEEC IF
CGGAGAAAGCAAATGAACGA (SEQ ID NO: 103)
SPCH
At5g53210
SPEEC IR
CCACAACTCCTCCTATGATCG (SEQ ID NO: 104)
PP2A
At1g13320
PP2A EF
TCCGAGATCACATGTTCCAA (SEQ ID NO: 105)
PP2A
At1g13320
PP2A ER
TCATCACATTGTCAATAGATTGGAG (SEQ ID NO: 106)
PP2A
At1g13320
PP2A IF
ATTCCGATAGTCGACCAAGC (SEQ ID NO: 107)
PP2A
At1g13320
PP2A IR
TGCGAAATACCGAACATCAA (SEQ ID NO: 108)
SAND
AT2G28390
SAND EF
CCCGACATATCTGTGGGAAC (SEQ ID NO: 109)
SAND
AT2G28390
SAND ER
TGGGGTCCCAATCCTTTTAC (SEQ ID NO: 110)
SAND
AT2G28390
SAND IF
GGAATTCTCACCCCCCAGTAAC (SEQ ID NO: 111)
SAND
AT2G28390
SAND IR
GGGTCCCAATCCTTTTACA (SEQ ID NO: 112)
Example 2
Inherited Acquired Drought Tolerance Induced by Low Relative Humidity in Arabidopsis
[0094] When parental plants are grown under control relative humidity, the imposition of a short period of drought caused a marked and significant reduction in chlorophyll content ( FIG. 4 ; Gen1 controlRH) and total plant dry mass ( FIG. 5 ; Gen1 controlRH). In contrast, when the same genotypes were grown under constant low relative humidity (LRH), the imposition of the same periodic drought did cause a fall in chlorophyll content relative to the undroughted controls ( FIG. 4 ; Gen1 LRH) and surprisingly was associated with an increase in final dry mass ( FIG. 5 ; Gen1 controlRH). Offspring generated from seed collected from plants exposed to control relative humidity behaved similarly in control conditions, with a marked drop in chlorophyll content ( FIG. 4 ; Control-Control) and final dry Biomass ( FIG. 5 ; Control-Control). Remarkably, offspring generated from seed collected from parent plants exposed to low relative humidity showed a significant increase in chlorophyll content when exposed to the same periodic drought ( FIG. 4 ; LRH-Control) and a similar significant increase in total dry biomass ( FIG. 5 ; LRH-Control). Thus, the parental exposure to LRH positively changed the response of the offspring to periodic drought. Even more remarkably, offspring from parental plants grown under low relative humidity when exposed to the same levels of low relative humidity as their parents, they had become insensitive to periodic drought in terms of chlorophyll content ( FIG. 4 ; LRH-LRH) and dry biomass ( FIG. 5 ; LRH-LRH). Unexpectedly, the effect of low RH pre-conditioning from the first generation was not heritable into a third generation, when grown under control conditions in terms of chlorophyll content ( FIG. 4 ; LRH-control-control) and biomass ( FIG. 5 ; LRH-control-control). Third generation offspring exposed to two successive LRH conditions followed by a control with and without drought behaved essentially similar to LRH-control treatments ( FIGS. 4 and 5 ). Mutants for de novo methylation (drm1/2) and (redundantly) the maintenance of methylation (cmt3) were similarly affected by drought in control RH but only the drm1/2 mutant was rescued by low RH pre-conditioning. Thus, the exposure of parental plants to variable relative humidity conditions incurred a changed epigenetic response to periodic drought in the same and following generations.
Methods—Plants and Growth Environment.
[0095] Seeds of Arabidopsis thaliana (L.) Heynh. ecotypes Landsberg erecta (Ler ref. NW20), Chromomethylase (cmt3 ref. N6365) and Domains rearranged methyltransferase 1/2 (drm1/drm2 ref. N6366) were supplied by NASC (Nottingham, UK). Seeds were sown in seedling compost (Sinclair, Lincoln, U.K.), germinated and grown in controlled environment growth cabinets (Saxcil, R. K. Saxton, Bredbury, Cheshire, U.K.) until harvest, according to ARBC guidelines except that the relative humidity of one cabinet was controlled at 45%±5 whilst the other was maintained at 65%±5. Harvested Ler seeds, supplied Ler seeds (as before) and supplied seeds for mutants (as before) were sown, germinated and grown under control RH before except that after 40 d half of the plants from each genotype were subjected to a drought treatment by withholding watering for 4 d. After this treatment, watering was restarted until seeds were harvested from each individual on day 64 (stage 9.70). Growth cabinets were swapped and no stratification was applied. Different (rotated) growth chambers were used in each of the 4 repeated experiments to accommodate for growth chamber effects (Sanyo Gallenkamp, Loughborough, U.K.). Each time, stomatal density (stomata mm −2 ) and index (percentage of epidermal cells forming stomata) were assessed at the same stage of growth by microscopic examination of impressions of the abaxial leaf surface (as described above). The complete dry biomass and seed mass of individual harvested plants were weighed and seeds counted, following threshing through a series of graded meshes, by capturing a digital image of collected seeds using an Epson Perfection 3170 scanner (Epson (U.K.), Hemel Hempstead, U.K.) then particle analysis using ImageJ software version 1.37 (freeware NIH, USA).
Example 3
Inherited Increased Resistance to Pathogen Botrytis cynerea in Arabidopsis Offspring
[0096] It has been found that Arabidopsis plants when innoculated with a pathogenic strain of Botrytis cynerea , respond in the short term by activating the expression of specific disease resistance genes. At the same time the global methylation pattern of the plant genome also changes. Quite remarkably, however, seeds collected from these plants present a higher resistance to the pathogen when innoculated. The plants used are so inbred that the offspring are to all intents and purposes genetically identical to the parent.
[0097] Second generation wild type plants were sown to compare whether any changes at methylation level are transmitted to next generation. Morphological data revealed existence of a transgenerational acquired increased resistance to Botrytis cynerea on the wild type Langsberg erecta genotype while none of the methylation mutants showed such increase in resistance ( FIG. 6 ). Generation 2 plants were treated with Botrytis cynerea . Pictures show lesions associated to fungal infection three days after inoculation in Langsberg erecta. Offspring of non-inoculated plants (A), offspring of inoculated plants (B) Arrows point inoculated leaves. Detail of the inoculated leaves from offspring of non-inoculated plants (C), offspring of inoculated plants (D).
[0000]
TABLE 6
Estimation of the resistance to B. cynerea in A. thaliana Lansberg erecta (Wild type -
Laer) and methylation mutants drm1/2 (Drm), chr1 (Chr), cmt3-7 (Cmt) and kyp2 (Kyp) three
days after inoculation.
Cont: Offspring of non-inoculated plants.
Bot: offspring of inoculated plants.
Lighter shading indicates resistance to pathogen, darker shading susceptibility based on morphological analysis.
[0098] Analysis of global methylation changes induced by infection with Botrytis cynerea using MSAP (with the enzyme combination MspI/EcoRI that is sensitive to methylation on the CpHpG motif) did not show significant differences between infected and non infected plants ( FIG. 7 ). Conversely, when the enzyme combination HpaII/EcoRI (sensitive to methylation on the CpHpG and the CpG motiffs) was used, genotypes drm1/2 and chr1 showed a significant change on global DNA methylation induced by the infection with Botrytis . Surprisingly, no differences were found between treatments for genotypes Wild type—Laer and kyp2. While genotype cmt3-7 showed some degree of separation (not significant) between samples infected with Botrytis and those non-infected ( FIG. 8 ). Remarkably, observed changes on global DNA methylation associated to Botrytis infection present an inverse correlation with the acquired increased resistance described above. These results suggest that maintenance of DNA methylation is necessary to generate acquired resistance.
Methods—Plants and Growth Environment.
[0099] Seeds of Arabidopsis thaliana (L.) Heynh. ecotypes Landsberg erecta (Ler ref. NW20) and mutants Chromatin-remodeling ATPase (CHR1 ref. N30937) Chromomethylase (cmt3 ref N6365) and Domains rearranged methyltransferase 1/2 (drm1/drm2 ref. N6366) and Kryptonite-2 (KYP-2 ref. N6367) were acquired from the European Arabidopsis Stock Centre.
[0100] Plants were grown in seedling compost (Sinclair, Lincoln, U.K.) in 24 cell trays with 1 plant in each 4 cm×4 cm cell, germinated and grown in controlled environment growth cabinets (Saxcil, R. K. Saxton, Bredbury, Cheshire, U.K.) until harvest, according to ARBC guidelines. One cell was removed to allow for bottom watering. Seeds were germinated at 4° C. and grown for 1 week under glass before being transferred to experimental conditions in a controlled-environment growth room. The plants were grown at 22° C. under an 8 hour photoperiod (approx. 70 μmol/m 2 /s) to inhibit flowering. After 64 d, stage 9.70, seeds were harvested from each individual. The complete dry biomass and seed mass of individual harvested plants were weighed and seeds counted, following threshing through a series of graded meshes, by capturing a digital image of collected seeds using an Epson Perfection 3170 scanner (Epson (U.K.), Hemel Hempstead, U.K.) then particle analysis using ImageJ software version 1.37 (freeware NIH, USA).
Generation Zero (G0)
[0101] To homogenize and standardize the level of methylation across the plant material a Generation 0 (Five plants per genotype) was grown in standard conditions: 24° C. short days (8 h light/16 h darkness), under light intensity of 100 mol m −2 s −1 . It allowed excluding any possible epigenetic variation which could exist due to variable seed storage conditions. Seeds obtained from each single plant of each genotype of Generation 0 were used in the subsequent part experiment—growing Generation one (G1). Seeds were collected from a single individual to insure the maximum level of genetic homogeneity across the plant material. Harvested Ler seeds, supplied Ler seeds and harvested mutant seeds supplied seeds for mutants. Seeds were sown, germinated and grown as before except that growth cabinets were swapped.
Generation One (G1)
[0102] Four trays were planted (92 plants). Plant trays were randomly assigned for two different treatments (innoculation with Botrytis cynerea and control). Plants were inoculated with the necrotrophic gray mold fungus Botrytis cynerea (strain iMi 169558, International Mycological Institute, Kew, U.K.) five weeks after germination. Plants were treated with 1×10 5 spores mL −1 suspension, by placing 2 droplets directly on the upper side of leaf number five (in order to ensure that they were at the same developmental stage) using a pipette. Seven days after inoculation, leaf six was sampled from half of the plants from each treatment and sampled plants were discarded. Seeds were collected from five of the remaining individuals and pooled to obtain a significant representation of the epigenetic variability induced by the treatments. Harvested Ler seeds, supplied Ler seeds and harvested mutant seeds supplied seeds for mutants. Seeds were sown, germinated and grown as before except that growth cabinets were swapped in the subsequent part experiment—growing Generation one (G2).
Generation One (G2)
[0103] Eight trays were planted (184 plants). Plant trays were randomly assigned for two different treatments (innoculation with Botrytis cynerea and control) as described above. Plants arising from seeds obtained from treated and untreated plants were inoculated again (see Table 6) as described above. Five days after inoculation pictures were taken from the whole plant and inoculated leaves for each of the genotype-G1-G2 treatment groups for documentation and image analysis. Susceptibility or resistance to fungal infection was assessed by measuring the size and intensity of the lesions resulting from Botrytis cynerea inoculation. Seven days after inoculation, leaf six was sampled from half of the plants from each treatment and sampled plants were discarded. Seeds were collected from five of the remaining individuals and pooled to obtain a significant representation of the epigenetic variability induced by the treatments. Generation 2 plants were looked at, specifically morphological changes associated with different background (G1treatment) within the same G2 treatment group.
[0000]
TABLE 7
Treatment/Generation
Control G1
Botrytis G1
Control G2
CC
BC
Botrytis G2
CB
BB
Methods—DNA Extraction
[0104] All DNA extractions were carried out using kits from Qiagen following the manufacturer's instructions. The DNeasy® plant mini kit was used for extracting DNA from A. Thaliana samples from 23 out the 46 plants per treatment. Reagents discussed below all derive from this kit.
[0105] Approximately 100 mg of plant tissue was disrupted in liquid nitrogen in a 1.5 ml microcentrifuge tube using a pair of scissors. Immediately, without allowing the tissue to thaw, 400 μl of lysis buffer AP1 preheated to 65° C. and 4 μl of RNase A were added to each tube. The contents were mixed by inversion and incubated at 65° C. for 10 min with occasional mixing every 2-3 min.
[0106] Following this, 130 μl of AP2 buffer was added to each sample and the tubes were incubated on ice for 5 min to precipitate the proteins and polysaccharides. Tubes were then subjected to centrifugation for 5 min at 13,000 rpm to precipitate viscous lysates and other solids.
[0107] The supernatant was then transferred to a QIAshredder™ column (with silica gel matrix) and centrifuged at 13,000 rpm for 2 min to remove precipitates and cell debris. The column flow-through was collected and transferred into a fresh tube and mixed with 0.5 volumes of wash buffer and 1 volume of ethanol. This mixture was transferred into a second DNeasy mini spin column and subjected to centrifugation at 8,000 rpm for 1 min. The flow-through was discarded since DNA molecules are retained on the column. The bound DNA was washed twice by passing 500 μl of wash buffer AW through the column by centrifugation at 8,000 rpm for 1 min.
[0108] Subsequently, the membrane was dried by centrifugation at 13,000 rpm for 1 min after the addition of 100 μl of buffer AE preheated to 65° C. and incubation for 5 min at room temperature.
Methods—Quantification by Agarose Gel
[0109] Aliquots of DNA (1-5 μl) were subjected to 1% (w/v) agarose gel electrophoresis to determine quality and quantity of DNA present. The gel was prepared by dissolving of appropriated quantity of agarose in the appropriate volume of 1×TAE buffer (40 mM tris-acetate, 1 mM EDTA) followed by heating in a microwave oven until all the agarose had melted. The gel solution was cooled to ˜50° C. before adding 10 mg/ml ethidium bromide solution to a final concentration of 0.35 μg/ml and then poured into a casting tray with an appropriate comb in place to create the loading well.
[0110] When set, the gel was transferred into a horizontal electrophoresis apparatus with the gel comb at the cathode end. The gel comb was removed and sufficient 1×TAE buffer was added to the electrode chamber to cover the gel by approximately 1 mm. Prepared DNA samples (5 μl DNA: 1 μl blue loading dye [0.23% (w/v) bromophenol blue, 60 mM EDTA, 40% (w/v) sucrose]) were then loaded into the gel wells. HyperLadderII (Bioline, BIO-33040) size markers were loaded into the flanking lanes. The gels were subjected to electrophoresis at constant voltages ranging from 3-5 V/cm for 15-60 min. The DNA was visualized using a UV transilluminator (320 nm wavelength).
Methods—Methylation-Sensitive Amplified Fragment Length Polymorphism
[0111] Methylation-Sensitive Amplified fragment length polymorphism (AFLP) was performed on a randomly selected eight DNA samples per treatment and was based on the AFLP protocol described by Vos et al (1995) but using isoschizomers targeting the same recognition motif.
[0112] The basis of the technique is the detection of restricted fragments of genomic DNA through polymase chain reaction (PCR) amplification. It allows the creation of fingerprints from DNA of any origin or complexity using a limited set of generic primers and needs no prior knowledge of sequences. The use of restriction enzymes sensitive to methylation adapts this method for detection of methylation.
[0113] The DNA was restricted with 2 restriction enzymes, one rare and one common cutter sensitive to cytosine methylation. Two different restrictions were carried out with isoschizomers of the common cutter sensitive to different types of cytosine methylation. All enzymes were obtained from Fermentas, Canada.
[0114] MspI enzyme: Cuts between the two cytosines of the sequence 5′CCGG 3′ and its action is prevented by methylation on the first C but not by methylation on the second C.
[0115] HpaII enzyme: Cuts between the two cytosines of the sequence 5′CCGG 3′ and its action is prevented by methylation on the second C but not by methylation on the first C.
[0000]
TABLE 8
Restriction reactions
MspI/EcoRI
HpaII/EcoRI
DNA
10-25
μl
DNA (300 ng)
10-25
μl
(300 ng)
Tango buffer
7
μl
Tango buffer
3
μl
(10X)
(10X)
MspI
2
μl
HpaII (10 u/μl)
1
μl
(10 u/μl)
EcoRI
1
μl
Water
to make up 30
μl
(10 u/μl)
Water
to make up 35
μl
Incubated at 37° C. for 2 h
before adding:
Incubated at 37° C. for 3 h
EcoRI (10 u/μl)
1
μl
Tango buffer
3.75
μl
(10X)
Incubated at 37° C. for a further 1 h
[0116] Adaptors specific to the restriction sites are ligated onto the DNA to allow for the amplification of fragments with generic primers and without the need for sequence information to be obtained first. All enzymes were from Fermentas and the adaptors were from Sigma-Genosys Ltd.
[0000]
TABLE 9
Adaptor structure
EcoRI
MspI/HpaII
Forward
5′ CTCGTAGACTGCGTACC
5′ GACGATGAGTCTCGAT
3′
3′
(SEQ ID NO: 120)
(SEQ ID NO: 121)
Reverse
3′ CTGACGCATGGTTAA 5′
3′ TACTCAGAGCTAGC 5′
(SEQ ID NO: 122)
(SEQ ID NO: 123)
[0117] An adaptor mix was created by combining 1 nM of the EcoRI adaptor and 10 nM of the MspI/HpaII adaptor.
[0000]
TABLE 10
Ligation reaction
Digested DNA
35 μl
Ligation buffer (10X)
5 μl
T4 ligase (1 u/μl)
1.4 μl
Adaptor mix
5 μl
Water
3.6 μl
Incubated at room temperature overnight.
[0118] The amplification rounds were carried out using one oligonucleotide primer that corresponded to the EcoRI ends and one oligonucleotide primer that corresponded to the MspI/HpaII ends. The first round of amplification reduces the number of possible fragments by the addition of one extra base at the 3′ end of the primer, while the second round of amplification further reduces the amount of possible fragments by the addition of one or two addition bases at the 3′ end of the primer. The second round EcoRI primers were labelled 6-Fam (Carboxyfluorescein) to allow visualisation of the products.
[0000]
TABLE 11
Pre-amplification primers
EcoRI
MspI/HpaII
5′ AGACTGCGTACCAATTCA 3′
5′ GATGAGTCTCGATCGGA 3′
(SEQ ID NO: 124)
(SEQ ID NO: 125)
[0000]
TABLE 12
Pre-amplification PCR mix
Restricted + ligated DNA (1/5)
3 μl
PCR Ready mix
10 μl
EcoRI primer + A(10 μM)
0.8 μl
HpaII/MspI primer + A
0.8 μl
(10 μM)
Water
5.4 μl
[0000]
TABLE 13
Pre-amplification PCR program
95° C.
10 mins
95° C.
30 sec
20 cycles
60° C.
1 min
72° C.
1 min
72° C.
2 min
[0000]
TABLE 14
Selective amplification primers
EcoRI
HpaII/MspI
5′ AGACTGCGTACCATTCAC 3′
5′ GATGAGTCTCGATCGGACT 3′
(SEQ ID NO: 126)
(SEQ ID NO: 127)
5′ AGACTGCGTACCATTCAA 3′
5′ GATGAGTCTCGATCGGAAT 3′
(SEQ ID NO: 128)
(SEQ ID NO: 129)
5′ AGACTGCGTACCATTCAG 3′
5′ GATGAGTCTCGATCGGATC 3′
(SEQ ID NO: 130)
(SEQ ID NO: 131)
5′ AGACTGCGTACCATTCAT 3′
(SEQ ID NO: 132)
[0000]
TABLE 15
Selective amplification PCR mix
Pre-amp DNA (1/15)
5 μl
PCR Ready mix
10 μl
EcoRI primer + AX (10 μM)
0.8 μl
HpaII/MspI primer + AXX
1 μl
(1 μM)
Water
3.2 μl
[0000]
TABLE 16
Touchdown PCR program for selective amplification.
95° C.
10 mins
95° C.
30 sec
12 cycles
60° C. down 0.7° C. per cycle
30 sec
72° C.
1 min
95° C.
30 sec
23 cycles
56.6° C.
1 min
72° C.
1 min
72° C.
2 min
[0119] The products of the selective amplification step were run on Applied Biosystems Genetic Analyzer. The results were visualised and interpreted using GeneMapper analysis software and exported into Microsoft Excel for further analysis.
[0120] Each band within the AFLP protocol was considered to be a single allele of a single locus. For each treatment, the allele identity for each locus was first assigned in a simple qualitative manner 1 (present) or 0 (absent) for each replicate individual. A locus was considered to differ between pairs of stress treatments or between the control and a stress treatment if the allelic profile of individuals for the locus differed by three or more individuals (e.g. 11111111 versus 11111000 would be considered to differ whereas 11111111 vs 00111111 would not). Multivariate analysis (Principal Co-ordinate analysis) was carried out using GenAlex (http://www.kovcomp.co.u/mvsp/).
[0121] As a result of the dominant nature of AFLP markers, part of the epigenetic variation between individuals is not captured in presence absence scores (for instance, because of cell type-specific methylation changes). However, these changes might contribute to meaningful variation in fragment peak intensities. Although the relationship between initial fragment copy number and peak height is not linear (for instance, because of PCR steps in the AFLP protocol) (Rodriguez Lopez et al 2004, Verhoeven et al 2009), intensity data may contain at least some biological information on epigenetic variation that can be captured using quantitative analysis (Castiglioni et al., 1999; Klahr et al., 2004). A second approach was therefore used to analyze quantitatively a smaller set of MS-AFLP markers (monomorphic in presence/absence scoring) for which fragment intensity scores were obtained using GeneMapper_software. Raw intensity scores were normalized by dividing each fragment peak height score by the total fluorescence value of all fragments obtained from each sample. This normalization accounts for overall differences in intensity scores between samples, for instance as a result of slight differences between samples in initial DNA concentrations. Normalized intensities were subjected to principal component analysis using Minitab 15 (http://www.minitab.com/en-GB/default.apsx?WT.srch=1&WT.mc_id=SE004815).
[0122] It should be understood that various changes and modifications to the presently preferred embodiments described herein will be apparent to those skilled in the art. Such changes and modifications can be made without departing from the spirit and scope of the present invention and without diminishing its attendant advantages. It is therefore intended that such changes and modifications are covered by the appended claims.
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65. Li, L. C. & Dahiya, R. MethPrimer: designing primers for methylation PCRs. Bioinformatics 18, 1427-31 (2002). | Provided are methods for the production of a stress tolerant plant or precursor thereof. The methods comprise (i) subjecting one or more parental plants to one or more stress conditions selected from unfavourable conditions relating to relative humidity, water availability, periodic drought, nutrients, sunlight, wind, temperature, pH, exogenous chemicals, chemical toxins such as salt, herbivory, prophylactic chemicals, fertilizers, pathogen attack such as bacterial, fungal, or virus infection and pest infestation; and (ii) generating offspring from said one or more parental plants. The offspring show enhanced tolerance relative to the one or more parental plants to one or more stress conditions selected from unfavourable conditions relating to relative humidity, water availability, periodic drought, nutrients, sunlight, wind, temperature, pH, exogenous chemicals, chemical toxins such as salt, herbivory, prophylactic chemicals, fertilizers, pathogen attack such as bacterial, fungal, or virus infection and pest infestation. Also provided are plants, or precursor thereof, produced by the methods and assays for identifying a plant, or precursor thereof, produced by the methods. | 0 |
BACKGROUND
[0001] 1. Field of the Invention
[0002] The present invention relates generally to helmets used as protective gear.
[0003] 2. Description of Related Art
[0004] Helmets are well known in the art to be securely fashioned to a head and provide padding in an attempt to absorb impact. Most helmets are designed to prevent skull injury and most testing systems test for this ability. Recently the concept of brain injury separate from skull injury has come to light and helmets are not typically designed to prevent such injuries well. Current helmets may dampen high crushing forces, but they do nothing to reduce against rotational forces that can damage the brain and the upper spine.
[0005] A need exists, therefore, for a helmet that protects the brain and upper spine as well as the skull.
[0006] All references cited herein are incorporated by reference to the maximum extent allowable by law. To the extent a reference may not be fully incorporated herein, it is incorporated by reference for background purposes and indicative of the knowledge of one of ordinary skill in the art.
BRIEF SUMMARY OF THE INVENTION
[0007] The problems presented in typical helmets are solved by providing a helmet with two shells connected by a plurality of discrete elastomeric elements.
[0008] Other objects, features, and advantages of the present invention will become apparent with reference to the drawings and detailed description that follow.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] FIG. 1 is a perspective view of a helmet;
[0010] FIG. 2 is a side view of the helmet of FIG. 1 ;
[0011] FIG. 3 is a front view of the helmet of FIG. 1 showing the sectional line for FIG. 4 ;
[0012] FIG. 4 is a sectional view of the helmet of FIG. 3 ; and
[0013] FIG. 5 is a close up sectional view of the helmet of FIG. 4 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0014] All references cited herein are incorporated by reference to the maximum extent allowable by law. To the extent a reference may not be fully incorporated herein, it is incorporated by reference for background purposes and indicative of the knowledge of one of ordinary skill in the art.
[0015] In the following detailed description of the preferred embodiments, reference is made to the accompanying drawings that form a part hereof, and in which is shown by way of illustration specific preferred embodiments in which the invention may be practiced. These embodiments are described in sufficient detail to enable those skilled in the art to practice the invention, and it is understood that other embodiments may be utilized and that logical mechanical and electrical changes may be made without departing from the spirit or scope of the invention. To avoid detail not necessary to enable those skilled in the art to practice the invention, the description may omit certain information known to those skilled in the art. The following detailed description is, therefore, not to be taken in a limiting sense, and the scope of the present invention is defined only by the appended claims.
[0016] FIG. 1 is a perspective view of a helmet 10 having an outer shell 12 and an inner shell 14 connected to each other by a plurality of discrete elastomeric elements 16 . The elastomeric elements 16 are only partially viewable in this view as they extend through the outer shell 12 . Outer shell 12 and inner shell 14 are both made of relatively stiff plastics such as polycarbonates or other materials with similar stiffness and toughness, including mixtures of different materials and layers of different materials combined into a single shell. If a helmet 10 has a chinstrap 18 then chinstrap 18 will be secured to inner shell 14 , not outer shell 12 .
[0017] FIG. 2 is a side view of the helmet 10 of FIG. 1 showing the profile of outer shell 12 and a layout of elastomeric elements 16 . If a helmet 10 has a facemask 20 or visor 22 then facemask 20 or visor 22 will be attached to outer shell 12 . Other optional equipment attached to the helmet will be attached to the outer shell 12 unless the optional equipment is intended to touch a head, such as the chinstrap 18 or pads 24 , shown in FIG. 3
[0018] FIG. 3 is a front view of the helmet of FIG. 1 showing the sectional line for FIG. 4 . Various optional aspects of the helmet are shown from this view such as those attached to the inner shell 14 like the pads 24 and chinstrap 18 .
[0019] FIG. 4 is a sectional view of the helmet 10 of FIG. 3 more clearly showing an inside view of helmet 10 and inner shell 14 in particular. Elastomeric elements 16 are shown extending through inner shell 14 .
[0020] FIG. 5 is a close up sectional view of the helmet 10 of FIG. 4 to show the relationship between elastomeric elements 16 and inner shell 14 and outer shell 12 . Both inner shell 14 and outer shell 12 have bore holes 26 placed in a pattern such that when inner shell 14 is placed within outer shell 12 the bore holes substantially align. Each borehole 26 has a recess 28 . For outer shell 12 the recess 28 is on an outer surface 36 while for inner shell 14 the recess 28 is on an inner surface 38 .
[0021] Elastomeric elements 16 are comprised of a body 30 , shanks 32 extending from the body 30 , and heads 34 attached to shanks 32 . Body 30 sits between outer shell 12 and inner shell 14 , while shanks 32 extend through boreholes 26 in inner shell 14 and outer shell 12 . Heads 34 are shaped to fit recesses 28 in the outer surface 36 of outer shell 12 and inner surface 38 of inner shell 14 . Elements 16 are made of elastomeric materials such as urethane, silicone, or other material with similar elastomeric properties, including mixtures of materials or combinations of materials within the same elastomeric element. The elements 16 are placed in aligning boreholes 26 to secure inner shell 14 within outer shell 12 and provide an elastic connection between inner shell 14 and outer shell 12 that allows outer shell 12 to rotate relative to inner shell 14 as well as absorb shocks applied to outer shell 12 so that they are not fully transmitted to inner shell 14 .
[0022] As shown on one element 16 in both FIG. 4 and FIG. 5 an element 16 may have placement strands 40 . Placement strands 40 may be cast into elastomeric element 16 when element 16 is formed. Placement strands 40 may be made of suitable wire, chord, string or twine. If the placement strands 40 are cast in the elastomeric elements 16 when they are formed, the strands 40 should be made of a material with a higher melting temperature than the material used in the elastomeric elements 16 . Placements strands 40 are used to align the elastomeric elements 16 with bore holes 26 when locating the inner shell 14 within the outer shell 12 . For example, elastomeric elements 16 may have one end fitted to bore holes 26 in the inner shell 14 and then placement strands 40 would be threaded through the corresponding bore holes 26 in outer shell 12 . As inner shell 14 is moved into place near outer shell 12 the placement strands 40 may be pulled to align each elastomeric element 16 with its corresponding bore hole in outer shell 12 . Once the elastomeric elements 16 are aligned with bore holes 26 in outer shell 12 the placement strands may be used to pull each elastomeric element 16 into engagement with its corresponding bore hole in outer shell 12 , by pulling the heads 34 through the bore hole 26 to rest in the recess 28 . Placement strands may extend from just one end of the elastomeric elements or from both ends to allow for adjustment if an elastomeric element 16 is pulled too hard during placement. After placement the placement strands 40 may be removed from the elastomeric elements 16 , typically by trimming them off with scissors or a razor blade.
[0023] Other methods for placement may be used for elastomeric elements 16 , but placement strands 40 are one placement method that can be done by hand.
[0024] Even thought he embodiment shown in this application is in a sports helmet with several optional features the basic concept is easily applicable to military helmets, construction helmets, safety helmets, and other helmet applications. Also, the basic concept may be used in helmets with less of the optional features, such as a football helmet with no visor.
[0025] It should be apparent from the foregoing that an invention having significant advantages has been provided. While the invention is shown in only a few of its forms, it is not just limited but is susceptible to various changes and modifications without departing from the spirit thereof. | A helmet having an outer shell and an inner shell placed within the outer shell. The inner shell attached to the outer shell by a plurality of elastomeric elements to isolate the inner shell from impacts and rotational forces applied to the outer shell. | 0 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims the priority, under 35 U.S.C. §119, of German application DE 10 2015 207 311.4, filed Apr. 22, 2015; the prior application is herewith incorporated by reference in its entirety.
BACKGROUND OF THE INVENTION
Field of the Invention
[0002] The invention relates to a domestic refrigeration appliance having a heat-insulated carcass which has an inner container with a cool able interior space for storing food, a refrigeration device for cooling the cool able interior space and an electromechanical opening assisting device, as well as a door leaf mounted pivotable relative to the heat-insulated carcass for opening and closing the cool able interior space, or a drawer which in the closed state is pushed into the cool able interior space in order to close it, and in the open state is at least partially withdrawn from the cool able interior space. The electromechanical opening assisting device contains an electromechanical actuator which is configured, on activation, to open the closed door leaf or the closed drawer automatically at least partially by displacement of a control body of the electromechanical opening assisting device.
[0003] The invention further relates to a method for operating a domestic refrigeration appliance of this type.
[0004] Published, non-prosecuted German patent application DE 10 2006 061 083 A1, corresponding to U.S. Pat. No. 9,062,911, discloses a domestic refrigeration appliance which has a heat-insulated carcass with an inner container. The inner container delimits a cool able interior space. The domestic refrigeration appliance contains a door leaf which is pivotable relative to the carcass to open and close the interior space and a door opening aid which has a control body and an air pressure sensor which is configured to determine an air pressure change within the interior space due to a pushing and/or pulling on the closed door leaf, in order thereupon to open the closed door leaf automatically at least partially by means of the control body.
SUMMARY OF THE INVENTION
[0005] It is an object of the invention to provide a domestic refrigeration appliance with an electromechanical opening assisting device for assisted opening of a closed door leaf or a closed drawer which is particularly reliable to operate.
[0006] The object of the invention is achieved with a domestic refrigeration appliance having a heat-insulated carcass which has an inner container with a cool able interior space for storing food, a refrigeration device for cooling the cool able interior space and an electromechanical opening assisting device, as well as a door leaf mounted pivotable relative to the heat-insulated carcass for opening and closing the cool able interior space, or a drawer which in the closed state is pushed into the cool able interior space in order to close it, and in the open state is at least partially withdrawn from the cool able interior space. The electromechanical opening assisting device contains an electromechanical actuator which is configured, on activation, to open the closed door leaf or the closed drawer automatically at least partially by displacement of a control body of the electromechanical opening assisting device. The electromechanical actuator contains an automatically displaceable base body, a plunger mounted in the base body as the control body and an overload protection device which arrests the plunger in the base body and is configured to fix the plunger rigidly in the base body, for as long as an impact force acting on the plunger remains smaller than a pre-determined trigger force and to release the plunger from the base body as soon as an impact force acting on the plunger exceeds the trigger force.
[0007] A corresponding electromechanical opening assisting device can contain an electromechanical actuator with an electric motor, a drive pinion, a double-toothing crown wheel and a toothed rack, the drive pinion being linked to a motor shaft of the motor and meshing with the input toothing of the double-toothing crown wheel, the output toothing of the double-toothing crown wheel meshing with a toothed rack profile of the toothed rack and the toothed rack being connected to the control body.
[0008] In the case of a door leaf, it is preferably mounted pivotable relative to an axis which preferably extends vertically. In addition, or alternatively to the door leaf, the domestic refrigeration appliance according to the invention can have a drawer which, in the closed state, is pushed into the cool able interior space in order to close it and, in the open state, is at least partially withdrawn from the cool able interior space. In such a case, the electromechanical opening assisting device is configured to assist an activation of the electromechanical opening assisting device triggered due to a pushing and/or pulling on the closed drawer to open or to assist the opening of the closed drawer by the electromechanical opening assisting device at least partially.
[0009] The refrigeration device is preferably a refrigerant circuit. The refrigerant circuit contains a compressor and, in particular, a condenser connected downstream of the compressor, a throttle device connected downstream of the condenser and an evaporator which is arranged between the throttle device and the compressor.
[0010] Preferably mounted on the side of the door leaf or the drawer facing toward the cool able interior space is an elastic magnetic seal which, with the door leaf closed or with the drawer closed, lies sealingly against the heat-insulated carcass. The magnetic seal is elastic so that in the event of pushing on the closed door leaf or on the closed drawer, the door leaf or drawer moves a little in the direction of the cool able interior space, so that the air pressure within the interior space changes. Due to the elastic magnetic seal, in the event of pulling on the closed door leaf or on the closed drawer, the magnetic seal does not detach immediately from the heat-insulated carcass, so that the air pressure within the cool able interior space changes.
[0011] Such a change of the air pressure can be recognized automatically, for example, by an air pressure sensor, so that the wish of a person to open the closed door leaf or the closed drawer can be concluded. Thus a control device connected to the air pressure sensor can, for example, automatically activate the electromechanical opening assisting device. However, the electromechanical opening assisting device according to the invention can also be activated in another way, for example, by a button to be operated manually or by other types of sensor which can recognize or at least predictively determine an intention of a person wishing to open the closed door leaf or the closed drawer.
[0012] The electromechanical opening assisting device actuates a control body, preferably a plunger which can be moved automatically, for example, by an actuator, from a driven in to a driven out position, in order to open the closed door leaf or the closed drawer at least partially, preferably at least so far that the magnetic seal detaches from the heat-insulated carcass.
[0013] In that the electromechanical actuator contains an automatically displaceable base body, a plunger mounted in the base body as the control body and an overload protection device which arrests the plunger in the base body, and is configured to fix the plunger rigidly in the base body for as long as an impact force acting upon the plunger remains smaller than a pre-determined trigger force and to release the plunger from the base body as soon as an impact force acting on the plunger exceeds the trigger force, a type of safety coupling is provided which ensures that in the case of a force exerted on the plunger that would be enough, for example, to destroy the gearing or the motor mechanically. The plunger is separated from the base body so that the plunger can avoid this damaging force and the force is therefore not transferred to components, in particular, to the gearing or the motor. By means of the overload protection device, the opening assisting device is protected against destruction.
[0014] In general, the electromechanical opening assisting device can comprise, quite generally, a housing, in particular two housing halves, in which at least the electric motor, the drive pinion, the double-toothing crown wheel, the toothed rack, the at least one rolling body and the control body are arranged or mounted or fastened. One or more of these components can be made of glass fiber-reinforced polyamide (PA-GF).
[0015] The toothed rack transfers the linear motion to the control body. The toothed rack is provided on the base body. The base body can have a receptacle into which the control body, in particular the plunger is inserted and locked. The control body, in particular the plunger, can have a cap at its free end. The cap can be, for example, pushed or screwed onto the end of the control body, in particular the plunger. In particular, in the case of a control body or plunger made of a metallic material such as steel, the cap can be made of plastics. The cap touches the door leaf to be opened or the drawer front to be opened on the respective inside thereof, at least during the automatic opening process.
[0016] The toothed rack can have a first rolling surface on a toothed rack wall opposite the toothed rack profile on which at least one rolling body, in particular at least one smooth-walled or toothed support roller rolls, the rolling body also being supported, on the side thereof opposite the first rolling surface, against the housing.
[0017] The electric motor can be a permanent-field alternating current synchronous motor in all the embodiment variants, the motor being operated, in particular, at a rotary speed of between 500 and 1,000 rotations per minute, in particular at a rotary speed of between 700 and 800 rotations per minute.
[0018] For the drive, a BLDC motor with an extremely flat construction and a torque of approximately 0.27 Nm at approximately 780 rpm can be used in order to be able to provide high torques at the lowest possible rotary speeds. Sinusoidal phase voltages/currents provide for a largely harmonic-free torque pattern in the drive.
[0019] The overload protection device can have a locking device connected to the base body and a counter-locking device corresponding to the locking device and connected to the plunger, wherein the locking device and the counter-locking device are configured to come into form-fitting mutual engagement during proper use of the electromechanical opening assisting device such that a drive force generated by the electromechanical actuator is transferable to the plunger and, on exceeding the pre-determined trigger force, the locking device and the counter-locking device are to be brought out of engagement by means of an impact force exceeding the pre-determined trigger force such that the plunger detaches from its rigid arrangement relative to the base body and becomes displaceable relative to the base body.
[0020] The overload protection device, in particular the locking device and the counter-locking device can thus be configured to maintain a rigid connection of the plunger and the base body for as long as the forces acting on the plunger give no cause to fear destruction of components of the opening assisting device. Depending on the design of the opening assisting device, a trigger force can be defined and pre-set, on exceeding which a destruction of components of the opening assisting device is to be feared. The overload protection device, in particular the locking device and the counter-locking device are thus configured to release the rigid connection of the plunger and the base body, i.e. to free or to make mobile the plunger as soon as the trigger force is exceeded.
[0021] The locking device can have at least one, in particular, two elastic locking hooks which are arranged mutually opposed and which, in an arrangement characterizing the proper use, engage behind at least one locking surface of the counter-locking device, the elastic locking hooks being configured, on reaching the pre-determined trigger force, to bend such that the at least one locking surface of the counter-locking device is released. If the locking surface of the counter-locking device has been released, then no further rigid connection of the plunger and the base body exists, so that the plunger can move relative to the base body and, in particular, by means of its movement the plunger can avoid the impact force which exceeds the trigger force.
[0022] The plunger can have, in particular, a circular cylindrical shaft, the base body can have a receptacle with an inner mantle wall matched to the outer mantle wall of the shaft and the shaft can be mounted in the receptacle linearly displaceable in the direction of its longitudinal extent when the overload protection device has released the plunger from the base body.
[0023] The plunger can have, in particular, a circular cylindrical shaft, the base body can have a receptacle with an inner mantle wall matched to the outer mantle wall of the shaft and the shaft is firmly held in the receptacle when the overload protection device, in an arrangement characterizing the proper use, fixes the plunger on the base body.
[0024] The plunger, in particular, the shaft of the plunger can preferably have, on an end opposite to the impact end of the plunger or the shaft, a pushed on or screwed on locking block which has the at least one locking surface of the counter-locking device.
[0025] In a triggered state of the overload protection device, this locking block then extends outwardly beyond the contour of the base body. In a basic position of the base body, the locking block which projects beyond the contour of the base body can lie against or make contact with a contact surface, for example, an inner wall of the housing of the opening assisting device. If the locking block is contained, in its non-triggered state, entirely within the contour of the base body, then in the basic position, the locking block cannot however lie against or make contact with the stop surface, such as for example an inner wall of the housing of the opening assisting device. Contact of the triggered locking block can be used to be able to detect the triggered state of the overload protection device, in particular to be able to detect it automatically, for example by a monitoring of a current rise in the motor which drives the base body or the plunger automatically. Alternatively or additionally, the motor can also be driven such that in a triggered state, in that the locking block projects outwardly beyond the contour of the base body, the base body is driven further in the direction of the stop surface or the inner wall of the housing, so that the locking block can spring back again into its non-triggered position within the base body where the locking block lies entirely within the contour of the base body and the plunger is now again coupled or connected rigidly to the base body.
[0026] In all embodiments, the base body and/or the locking block can be made of polyether ether ketone (PEEK). Through the use of polyether ether ketone (PEEK), a particularly stable modulus of elasticity can be achieved which is particularly largely independent, for example, of temperature changes or aging effects. This means that the trigger force of the overload protection device can be maintained particularly exactly.
[0027] The object of the invention is further solved by a method for operating a domestic refrigeration appliance as described. The method includes the following steps of:
a) electrically powered, automatic movement of the base body from a position activating the door leaf or the drawer into a basic position in which the overload protection device, in its non-triggered state, has a distance from a stop surface of the electromechanical opening assisting device, in particular an inner wall of a housing of the electromechanical opening assisting device and, in its triggered state, lies against the stop surface of the electromechanical opening assisting device, in particular against the inner wall of the housing of the electromechanical opening assisting device; b) automatic monitoring of a motor current of the electromechanical actuator of the electromechanical opening assisting device; and c) automatic signaling of the triggering of the overload protection device when, during the automatic monitoring of the motor current of the motor in the case of an electrically powered automatic movement of the base body into the basic position in the triggered state, a raised current uptake by the motor is determined as compared with an electrically powered automatic movement of the base body into the basic position in the non-triggered state.
[0031] Based on an automatic signaling of the triggering of the overload protection device, the control device of the domestic refrigeration appliance can, for example, indicate a fault on the domestic refrigeration appliance, particularly optically or acoustically, for example with a warning lamp. Alternatively or additionally, the control device of the domestic refrigeration appliance can automatically switch off the opening assisting device electrically. Alternatively or additionally, the control device of the domestic refrigeration appliance can control the opening assisting device automatically such that in a triggered state, in that the locking block projects outwardly beyond the contour of the base body, the base body is driven further in the direction of the stop surface or the inner wall of the housing, so that the locking block can spring back again into its non-triggered position within the base body where the locking block lies entirely within the contour of the base body and the plunger is now again coupled or connected rigidly to the base body.
[0032] Summarizing, in order to prevent gearing damage through improper overloading, a mechanical trigger mechanism can be integrated into the toothed rack of the drive unit. If, for example, the user pushes too strongly against an open door, a mechanical overload protection of this type is triggered. The resetting of the overload protection can take place by automatic or manual resetting of the plunger wherein the toothed rack and the plunger rod can lock into one another again and restore the force-fit via a special coupling element. The plunger rod can carry a locking body. The locking body has a special profile as the counter-bearing to the locking lugs of the spring elements. The spring elements are part of the toothed rack which can be configured as a glass fiber-reinforced plastics body. It is also possible to integrate the locking body or the locking profile into the toothed rack body and to fasten the elastic part on the plunger rod. By means of optional adjusting elements, the spring force and thus the trigger force can be adjusted more precisely.
[0033] According to a preferred embodiment of the domestic refrigeration appliance according to the invention, the assisting device has a housing within which substantially all the components of the assisting device are arranged. Preferably, in particular, all the electrical and any mechanical components necessary for the operation of the assisting device are arranged within the housing, possibly except for an electrical power supply. A control body is preferably also arranged in the housing, but then projects at least partially out of the housing at least in its driven out position. The housing of the assisting device is preferably made of plastics, in particular glass fiber-reinforced polyamide (PA-GF).
[0034] Other features which are considered as characteristic for the invention are set forth in the appended claims.
[0035] Although the invention is illustrated and described herein as embodied in a domestic refrigeration appliance with an overload protection device of an opening assisting device and associated method, it is nevertheless not intended to be limited to the details shown, since various modifications and structural changes may be made therein without departing from the spirit of the invention and within the scope and range of equivalents of the claims.
[0036] The construction and method of operation of the invention, however, together with additional objects and advantages thereof will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING
[0037] FIG. 1 is diagrammatic, perspective view of a domestic refrigeration appliance with a door leaf and an electromechanical opening assisting device for opening the door leaf according to the invention;
[0038] FIG. 2 is an illustration of a principle of the electromechanical opening assisting device;
[0039] FIG. 3 is a plan view of an embodiment of the electromechanical opening assisting device;
[0040] FIG. 4 is a perspective view of the electromechanical opening assisting device of FIG. 3 with a removed housing;
[0041] FIG. 5 is a perspective view of an overload protection device from the electromechanical opening assisting device of FIG. 4 in a non-triggered arrangement; and
[0042] FIG. 6 is a perspective view of the overload protection device from the electromechanical opening assisting device of FIG. 4 in a triggered arrangement.
DETAILED DESCRIPTION OF THE INVENTION
[0043] Referring now to the figures of the drawings in detail and first, particularly to FIG. 1 thereof, there is shown, in a perspective view, a domestic refrigeration appliance 1 which contains a heat-insulated carcass 2 with an inner container 3 which delimits a cool able interior space 4 . The cool able interior space 4 is provided for storing non-illustrated food.
[0044] In the case of the present exemplary embodiment, the domestic refrigeration appliance 1 has a pivotable door leaf 5 for closing the cool able interior space 4 . The door leaf is mounted, in particular, pivotable relative to a vertically extending axis. With the door leaf 5 open as shown in FIG. 1 , the cool able interior space 4 is accessible.
[0045] Arranged on the side of the door leaf 5 facing toward the cool able interior space 4 in the case of the present exemplary embodiment are a plurality of door storage units 6 for storing food. Arranged in the cool able interior space 4 are, in particular, a plurality of shelves 7 for storing food and arranged, in particular, in the lower region of the cool able interior space 4 is a drawer 8 in which, also, food can be stored.
[0046] The domestic refrigeration appliance 1 has a refrigeration device configured, in particular, as a refrigerant circuit for cooling the cool able interior space 4 . The refrigerant circuit has, in particular, a compressor, a condenser connected downstream of the compressor, a throttle device which is configured, in particular, as a throttle pipe or capillary pipe connected downstream of the condenser, and an evaporator which is arranged between the throttle device and the compressor. The compressor is preferably arranged within a mechanism chamber of the domestic refrigeration appliance 1 , which is arranged, in particular, behind the drawer 8 .
[0047] In the case of the present exemplary embodiment, the domestic refrigeration appliance 1 has an electronic control device 9 which is configured to control the refrigeration device, in particular the compressor of the refrigerant circuit in a manner that is commonly known to persons skilled in the art, such that the cool able interior space 4 has approximately a pre-determined or pre-determinable target temperature. The electronic control device 9 is preferably configured such that it regulates the temperature of the cool able interior space 4 . In order, if required, to obtain the target temperature of the cool able interior space 4 , the domestic refrigeration appliance 1 can have at least one temperature sensor (not shown in detail) which is connected to the electronic control device 9 .
[0048] The domestic refrigeration appliance 1 also has an electromechanical opening assisting device 20 which is configured at least to assist an opening of the closed door leaf 5 . FIG. 2 shows an illustration of the principle of the electromechanical opening assisting device 20 .
[0049] The electromechanical opening assisting device 20 is fastened, for example, in or on the carcass 2 and has a control body 21 , for example, a plunger which can be moved automatically by an actuator 22 of the electromechanical opening assisting device 20 from a driven in to a driven out position. In its driven in position, the plunger 21 permits closing of the door leaf 5 or the plunger 21 is pushed, on closing the door leaf 5 , into its driven in position. The actuator 22 has an electric motor 23 , a double-toothing crown wheel 24 and a toothed rack 25 .
[0050] In the case of the present exemplary embodiment, the domestic refrigeration appliance 1 has a magnetic seal 10 fastened on the side of the door leaf 5 facing toward the cool able interior space 4 , the magnetic seal lying, with the door leaf 5 closed, against the front face of the carcass 2 . The magnetic seal 10 is elastic so that in the event of pushing on the closed door leaf 5 , it moves a little in the direction of the cool able interior space 4 , so that the air pressure within the cool able interior space 4 changes. Due to the elastic magnetic seal 10 , in the event of pulling on the closed door leaf 5 , the magnetic seal 10 does not detach immediately from the carcass 2 , so that the air pressure within the cool able interior space 4 likewise changes.
[0051] In the case of the present exemplary embodiment, the electromechanical opening assisting device 20 is configured such that it recognizes the wish of a person to open the door leaf 5 as soon as the person pulls or pushes on the closed door leaf 5 . Thereupon, the actuator 22 automatically moves the plunger from its driven in position into its driven out position. During this movement, the plunger 21 pushes the door leaf 5 open at least so far that the magnetic seal 10 detaches from the carcass 2 so that the person can more easily open the door leaf 5 completely.
[0052] For example, based on a measurement and evaluation of the change in the air pressure within the cool able interior space 4 , a pulling or pushing on the door leaf 5 and therefore the wish of a person to open the closed door leaf 5 can thus be deduced. Accordingly, a sensor device which is per se known to a person skilled in the art and a corresponding control device can be provided in order to activate the electromechanical actuator 22 when the wish of a person to open the closed door leaf 5 is recognized so that the closed door leaf 5 or the closed drawer is opened automatically at least partially by displacement of the control body 21 by the electromechanical actuator 22 .
[0053] The domestic refrigeration appliance 1 can also have a drawer which is at least partially withdraw able from the cool able interior space 4 and is push able into the cool able interior space 4 . In the pushed in state, this drawer closes the cool able interior space 4 . If this drawer is at least partially withdrawn from the cool able interior space 4 , then it is opened. The electromechanical opening assisting device 20 can also be provided to recognize the wish to open the drawer and accordingly to open the drawer automatically at least partially.
[0054] In the case of the present exemplary embodiment, the electromechanical opening assisting device 20 is configured such that it recognizes the wish of a person to open this drawer as soon as the person pulls or pushes on the closed drawer. Thereupon, the actuator 22 automatically moves the plunger from its driven in position into its driven out position. During this movement, the plunger pushes the drawer open at least so far out of the cool able interior space 4 that a magnetic seal of the drawer detaches from the carcass 2 so that the person can more easily open the drawer completely.
[0055] The electromechanical actuator 22 has the electric motor 23 , a drive pinion 27 , the double-toothing crown wheel 24 and the toothed rack 25 . The drive pinion 27 is connected to a motor shaft 28 of the motor 23 . The drive pinion 27 meshes, as shown particularly in FIG. 3 , with an input toothing 24 a of the double-toothing crown wheel 24 . The double-toothing crown wheel 24 also has an output toothing 24 b which engages, as shown particularly in FIG. 4 , with a toothed rack profile 25 a of the toothed rack 25 . The toothed rack 25 is connected to the control body 21 .
[0056] In the exemplary embodiment, for example, as shown in FIG. 4 , the toothed rack 25 is provided on a base body 29 . The base body 29 has a receptacle 30 into which the control body 21 , in particular the plunger is inserted and locked. The control body 21 , in particular the plunger, has a cap 31 at its free end. The cap 31 can be, for example, pushed or screwed onto the end of the control body 21 , in particular the plunger. In particular, in the case of a control body 21 or plunger made of a metallic material such as steel, the cap 31 can be made of plastics. The cap 31 touches the door leaf 5 to be opened or the drawer front to be opened on the respective inside thereof, at least during the automatic opening process. The base body 29 also has a first cheek 32 a which supports the output toothing 24 b of the double-toothing crown wheel 24 axially.
[0057] On a toothed rack wall 33 of the toothed rack 25 or of a base body 29 lying opposite to the toothed rack profile 25 a, the base body 29 has a rolling surface 34 , in particular in the form of a wave profile. In the case of the present exemplary embodiment, two rolling bodies 35 in the form of toothed support rollers 35 a roll along the rolling surface 34 . In the case of the present exemplary embodiment, the toothed support rollers 35 a each have a wave profile. FIG. 3 shows that the rolling bodies 35 , in particular the support rollers 35 a are supported on a side of the rolling bodies 35 or the support rollers 35 a lying opposing the rolling surface 34 by a fixed second rolling surface 36 against the housing 26 . The second rolling surface 36 can be provided, as shown in FIG. 4 , on a separate support body 37 which is fastened on the housing 26 or constructed in one part, as shown in FIG. 3 , directly with an inner wall 38 of the housing 26 .
[0058] As FIGS. 5 and 6 , in particular, show, the overload protection device 39 has a locking device 40 connected to the base body 29 and a counter-locking device 41 corresponding to the locking device 40 connected to the plunger 21 a. The locking device 40 and the counter-locking device 41 are configured to come into form-fitting mutual engagement during proper use of the electromechanical opening assisting device 20 , as shown in FIG. 5 , such that a drive force generated by the electromechanical actuator 22 is transferable to the plunger 21 a and, on exceeding the pre-determined trigger force, the locking device 40 and the counter-locking device 41 are to be brought out of engagement by an impact force exceeding the pre-determined trigger force, as shown in FIG. 6 , such that the plunger 21 a detaches from its rigid arrangement relative to the base body 29 and becomes displaceable relative to the base body 29 . The displace ability is indicated in FIG. 6 by the arrow P.
[0059] In the case of the present exemplary embodiment, the locking device 40 has two elastic locking hooks 40 a, 40 b arranged mutually opposed which, in an arrangement characterizing the proper use ( FIG. 5 ), engage behind at least one locking surface 42 of the counter-locking device 41 , the elastic locking hooks 40 a, 40 b being configured, on reaching the pre-determined trigger force, to bend such that the at least one locking surface 42 of the counter-locking device 41 is released, as shown in FIG. 6 .
[0060] The plunger 21 a, in particular, the shaft of the plunger 21 a, preferably has, on a front end 43 opposite to the impact end of the plunger 21 a or the shaft, a pushed on or screwed on locking block 44 which has the at least one or, in the case of the present exemplary embodiment, two locking surfaces 42 of the counter-locking device 41 .
[0061] The following is a summary list of reference numerals and the corresponding structure used in the above description of the invention:
1 Domestic refrigeration appliance 2 Carcass 3 Inner container 4 Cool able interior space 5 Door leaf 6 Door storage unit 7 Shelf 8 Drawer 9 Electronic control device 10 Magnetic seal 20 Electromechanical opening assisting device 21 Control body 21 a Plunger 22 Electromechanical actuator 23 Motor 23 a Stator 23 b Rotor 24 Double-toothing crown wheel 24 a Input toothing 24 b Output toothing 25 Toothed rack 25 a Toothed rack profile 24 Housing 26 a First housing half 26 b Second housing half 27 Drive pinion 28 Motor shaft 29 Base body 30 Receptacle 31 Cap 32 a First cheek 32 b Second cheek 33 Toothed rack wall 34 First rolling surface 35 Rolling body 35 a Support rollers 36 Second rolling surface 37 Support body 38 Inner wall 39 Overload protection device 40 Locking means 40 a, 40 b Locking hooks 41 Counter-locking means 42 Locking surface 43 Front end 44 Locking block | A refrigerator has a heat-insulated carcass which has an inner container with a cool able interior space for storing food, a refrigeration device for cooling the interior space, an electromechanical opening assisting device, and a door leaf mounted to the carcass for opening and closing the interior space. The opening assisting device contains an actuator configured to open the door leaf automatically by displacement of a control body. The actuator has a displaceable base body, a plunger mounted in the base body as the control body and an overload protection device arresting the plunger in the base body. The overload protection device fixes the plunger rigidly in the base body, for as long as an impact force acting on the plunger remains smaller than a trigger force and to release the plunger from the base body as soon as an impact force acting on the plunger exceeds the trigger force. | 5 |
This is a continuation of application Ser. No. 08/426,151 filed Apr. 21, 1995, now abandoned.
BACKGROUND OF THE INVENTION
This invention relates to medical devices for introducing catheters or the like into the body and in particular into blood vessels of the body.
Catheter assemblies provide a reusable conduit for the passage of catheters and other medical devices, e.g., guidewires, through the body flesh into blood vessels or other body passageways. Catheter assemblies are well known in the art. U.S. Pat. No. 5,098,392 granted to Amplatz et al. discloses an introducer assembly having (1) an introducer element consisting of an elongated tubular member defining an introducer sheath and an introducer hub disposed at the proximal end of the introducer sheath which further defines an introducer conduit along a longitudinal axis, and (2) a dilation element having an elongated tubular member defining a dilator having a tapered distal end portion and a dilator hub disposed at the proximal end of the dilator, which is sized so that the dilator may be inserted through the conduit of the introducer hub and introducer sheath and that the dilator tapered distal portion extends beyond the introducer sheath distal end.
Prior to the use of the catheter assembly, a needle is inserted through the body flesh and into a blood vessel, and a guidewire is inserted into the blood vessel through the center passage of the needle. The needle is then removed leaving the guidewire in place. The introducer assembly is then inserted over the guidewire such that the tapered distal portion of the dilator acts to gradually expand the puncture opening to ease the passage of the introducer sheath into the blood vessel. After the introducer sheath has been inserted to a desired depth within the blood vessel, the dilator element is removed from within the introducer element. A catheter can then be inserted through the introducer sheath into the blood vessel. In addition to introducer-dilator assemblies, other catheter assemblies include the combination of an introducer sheath with obturators, sterile sleeves, Tuohy-Borst fittings and the like.
To prevent or minimize the loss of blood or bodily fluid after the catheter assembly is in place, a hemostasis gasket is typically incorporated in the catheter assembly. U.S. Pat. No. 5,098,383 to Amplatz et al. describes such a catheter introducer assembly incorporating a hemostasis gasket. The hemostasis gasket is designed to form a seal after the dilator element or the like has been removed thereby preventing blood or bodily fluid from exiting from the introducer element. After the dilator element has been removed, the catheter which is to be inserted into the blood vessel must be carefully inserted into and guided through and past the hemostasis gasket. As the distance between the proximal end of the hub of the introducer sheath and the hemostasis gasket increases, the gasket becomes less accessible making it increasingly difficult to insert the catheter past the gasket. Moreover, if the catheter being used is of a curved or pigtail design, the difficulty of inserting the catheter through the hemostasis gasket is compounded, and at times requires the user to straighten the catheter with a guidewire prior to insertion.
During the initial insertion of the catheter assembly, the body's resistance to the expansion of the puncture opening exerts forces on the distal portion of the dilator tending to push the distal end of the dilator rearwardly in the proximal direction into the introducer sheath. In order to ensure that the tapered distal portion of the dilator remains extended beyond the blunt distal end of the introducer sheath during the initial insertion of the catheter assembly, the dilator hub is releasably connected to the introducer hub.
Several means for releasably connecting the introducer hub and the hub of the other component of the catheter assembly, e.g., the dilator hub, are known in the prior art. Unfortunately, with some of these prior art designs, the interconnected hubs are prone to becoming accidently disengaged. Moreover, because of the depth of the introducer hub and the distance between the proximal end of the introducer hub and the hemostasis gasket, insertion of certain catheters, particularly those having a curved or pigtail design, into the introducer sheath after the dilator element has been removed, is difficult.
A prior art means for releasably connecting the dilator hub and introducer hub comprises rotatably engaging studs and complementary slots associated with the dilator and introducer hubs. U.S. Pat. No. 4,192,305 to Seberg discloses a catheter placement assembly having a needle and lumen wherein the needle and lumen are mechanically engaged by complementary means associated with the needle and lumen hubs, such as tabs associated with one hub and slots associated with the other hub. U.S. Pat. No. 4,946,443 to Hauser et al. discloses a catheter assembly having a releasable connecting means having a pin or stud associated with one hub that is received by a slot associated with the other hub. Medical assemblies having releasable connecting means of the pin-and-slot type are also disclosed in U.S. Pat. No. 4,609,370 to Morrison; U.S. Pat. No. 4,986,814 to Burney et al.; and U.S. Pat. No. 3,860,006 to Patel. These types of rotatably engaging releasable connecting means do not have a stop means for securely locking the pin within the slot and, therefore, are prone to accidental disengagement through the inadvertent rotation of the dilator hub.
Additionally, U.S. Pat. No. 5,098,393 to Amplatz et al. discloses that the dilator hub and introducer hub may be releasably connected by an axially engaging snap fit or friction fit connection. An axially aligned snap fit connection of the type disclosed in U.S. Pat. No. 5,098,393 is prone to accidental disengagement through the inadvertent application of a transverse force to the proximal end of the dilator hub. Moreover, while the axial alignment of the dilator and introducer hubs is maintained with such a releasable connection, rotational movement between the dilator and introducer hubs is permitted.
Upon an accidental disengagement of the dilator hub and introducer hub during the initial insertion of the catheter assembly, the tapered distal end of dilator would migrate proximally into the introducer sheath and the blunt distal end of the introducer sheath may be forced against the blood vessel. In that event, trauma to the blood vessel and body flesh surrounding the puncture site could result. Such trauma may result in the procedure being reinitiated at another location along the blood vessel or being abandoned altogether. Accidental disengagement of an obturator can result in kinling of the introducer sheath thus preventing further use of the sheath and requiring replacement with a new sheath. Similarly, disengagement of a sterile sleeve from the introducer sheath will compromise the required sterile environment. Further, disengagement of the Tuohy-Borst fitting from the introducer sheath can cause the catheter, which is received by the fitting and within the introducer, to move from its desired position in the patient.
An improved catheter assembly is disclosed in U.S. Pat. No. 5,391,152 to Patterson. This catheter assembly has an improved releasable interlock connection which comprises a first element having a hub with outwardly protruding radial tabs disposed at the distal end of the hub and a second element having a hub with two complementary slots and two interference fit protuberances disposed at the proximal portion of the second element hub A- which rotatably receive and secure the first element tabs. While the catheter assembly disclosed in U.S. Pat. No. 5,391,152 provides an improved "locking mechanism" when Adcompared to the "snap-fit" or "press-fit" interlock designs previously described in the art, the depth of the introducer hub and distance between the proximal end of the introducer hub and the hemostasis gasket makes insertion of a curved or pigtail catheter difficult.
Accordingly, it is an object of the present invention to provide a catheter assembly with a first and second catheter element (e.g., a dilator and an introducer, respectively), each element having a hub with an improved rotatably engageably releasable interlock connection and a rotational securement means which minimizes, and preferably eliminates, the risk of accidental disengagement of both the axial and rotational alignment of the first and second catheter element hubs. It is a further object of this invention to provide a catheter assembly having a reduced distance between the proximal end of the second catheter element hub (e.g., introducer) and the hemostasis gasket thereby permitting the catheter assembly to have a lower profile. A catheter assembly having a lower profile makes it easier, once the first catheter element (e.g., dilator) is inserted into the body and the second catheter element (e.g., introducer) removed, to insert a curved or pigtail catheter into the body through the second catheter element (e.g., introducer).
SUMMARY OF THE INVENTION
The present invention resides in the improvement of providing complementary threads on the component hubs of a catheter assembly, such as between a dilator hub and an introducer hub. These threads permit the user to rotatably engage (e.g., interlock or screw) the component hubs together, thus providing an improved and more secure engagement between the component hubs and thereby preventing accidental axial disengagement. The location of the threads permits the catheter assembly to have a profile which is lower then otherwise possible, thereby permitting easier access to the hemostasis gasket. The component hubs are also provided with a rotational securement means to inhibit accidental rotational disengagement. The rotational securement means can comprise complementary protuberances (e.g., projections, bulges, etc.) and recesses (e.g., depressions, cavities, etc.) so that when the protuberances are in contact with, and seated within, the recesses, accidental rotational disengagement is inhibited.
The catheter assembly of this invention comprises a first catheter element having a hub and a second catheter element having a hub. The hub of the first catheter element has a threaded distal portion and one or more protuberances disposed on the distal end of the hub. The hub of the second catheter element has a proximal threaded portion which is rotatably releasably engageable with the threaded distal portion of the first catheter element. One or more recesses are disposed on the proximal end of the hub of the second catheter element. The protuberances and recesses are complementary in nature. In other words, the protuberances of the first catheter element hub are sized and spaced such that when they are brought into contact with the recesses of the second catheter element hub as a result of the rotational engagement of the threaded portions of the first and second catheter element hubs, the protuberances of the first catheter element hub drop into, and become seated within, the locking recesses of the second catheter element hub. The size and location of the threaded portions of the first and second catheter element hubs combined with the protuberances and recesses permits the catheter assembly to have a lower profile while at the same time preventing accidental axial and rotational disengagement of the first and second catheter elements.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will be further described, by way of example, with reference to the accompanying drawings wherein:
FIG. 1 is perspective view of the proximal end of a catheter assembly made in accordance with this invention.
FIG. 2 is an enlarged perspective view of the proximal end of the dilator of the catheter assembly of FIG. 1.
FIG. 3 is a front-elevational view of the proximal end of the dilator hub of this invention.
FIG. 4 is a side-elevational view of the dilator hub when view along line 2--2 of FIG. 3.
FIG. 5 is an enlarged perspective view of the proximal end of the introducer of the catheter assembly of FIG. 1.
FIG. 6 is a longitudinal sectional view of the proximal end of the introducer of the catheter assembly of FIG. 1.
FIG. 7 is a side-elevational view of the introducer hub when viewed along line 5--5 of FIG. 6.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
It should be noted that while the following description will be specifically in the context of an introducer-dilator assembly, the invention is not so limited and is applicable to other catheter assemblies.
Referring to FIGS. 1 and 6, in a preferred embodiment, catheter assembly 10 comprises a dilator element 20 having a dilator hub 21 having a proximal and distal end and an introducer element 30 having an introducer hub 31 having a proximal and distal end. As will be described below, dilator hub 21 and introducer hub 31 may be rotatably engaged or interlocked. In this preferred embodiment, introducer hub 31 comprises a hemostasis gasket 38 disposed at the proximal end of hub 31 and a sidearm infusion leg 40. Hemostasis gasket 38 limits the leakage of blood or other bodily fluid through introducer element 30. The construction and operation of a hemostasis gasket is well known in the art. See. e.g., U.S. Pat. No. 5,098,393 to Amplatz et al. A tube and stopcock (NOT SHOWN) may be connected to sidearm infusion leg 40. If required, heparin or other chemicals may be directly administered into the blood vessel through sidearm infusion leg 40.
Further referring to FIGS. 1 and 2, in a preferred embodiment, dilator element 20 comprises a dilator 22 having a tapered distal portion 23 and a longitudinal dilator conduit 24 defining a longitudinal axis. Preferably, dilator 22 is formed of a semi-rigid polymer, such as polyvinyl chloride, polypropylene, polyethylene, polyethylene terephthalate, polyurethane, polytetrafluoroethylene, fluoroethylenepropylene or nylon. Dilator 22 is most preferably constructed of polyethylene. Dilator hub 21 is disposed at the proximal end of dilator 22. Dilator hub 21 includes a distal planar surface 26 having a port 28 and a bore at the center of the hub (NOT SHOWN) extending therethrough which communicates with dilator conduit 24. Preferably, dilator hub 21 is formed of a rigid polymer, such as polyethylene or acrylonitrile butadiene styrene (ABS).
Referring to FIGS. 2 and 3, in a preferred embodiment, centrally disposed on the distal planar surface 26 of dilator hub 21 is a threaded portion. The threaded portion comprises either outwardly or inwardly protruding threads 27. Threads 27 may be formed of the same materials as dilator hub 21. Threads 27 may be of unitary construction with dilator hub 21 or attached thereto in an integral fashion. In a more preferred embodiment, threads 27 are outwardly protruding or "male."
Referring to FIGS. 2, 3 and 4, in a preferred embodiment, at least one protuberance 29 is disposed on the distal planar surface of dilator hub 21. In a more preferred embodiment, a plurality of protuberances 29 are spaced equally on the distal planar surface 26 of dilator hub 21 along a circumference and extend radially from the center of the bore of hub 21.
Referring to FIGS. 1 and 5, in a preferred embodiment, introducer element 30 comprises an introducer sheath 32 with a distal portion 34 and a longitudinal introducer conduit 33 defining a longitudinal axis. Typically, the distal portion 34 of introducer sheath 32 is tapered, but it may be blunt. Preferably, introducer sheath 32 is formed of a semi-rigid polymer, such as polyvinyl chloride, polypropylene, polyethylene, polyethylene terephthalate, polyurethane, polytetrafluoroethylene, fluoroethylenepropylene or nylon. Introducer sheath 32 is most preferably constructed of a polyether block amide. Introducer hub 31 is disposed at the proximal end of introducer sheath 32. Introducer hub 31 includes a proximal planar surface 36 and a centrally disposed bore 35 which extends from the proximal planar surface 36 of introducer hub 31 through introducer hub 31 defining an inner surface which communicates with introducer conduit 33. Preferably, introducer hub 31 is formed of a rigid polymer, such as polyethylene or ABS.
Referring to FIGS. 5 and 6, in a preferred embodiment, the inner surface of bore 35 has a proximal threaded portion. The proximal threaded portion comprises either outwardly or inwardly protruding threads 37. Threads 37 are sized and spaced so that they are rotatably engageable with threads 27. Threads 37 may be formed of the same materials as introducer hub 31. Threads 37 may be of unitary construction with introducer hub 31 or attached thereto in an integral fashion. In a more preferred embodiment, threads 37 are inwardly protruding or "female."
Threads 27 and 37 are complementary and are sized and spaced such that they can be engaged when they are rotatably brought into contact. In a more preferred embodiment, threads 27 are double-lead male threads and threads 37 are double-lead female threads and are spaced and sized such dilator hub 21 has to be rotated less than about 180° to engage or disengage dilator hub 21 and introducer hub 31.
Referring to FIGS. S and 7, in a preferred embodiment, at least one recess 39 is disposed on the proximal planar surface 36 of introducer hub :31. In a more preferred embodiment, a plurality of recesses 39 are spaced equally on the proximal planar surface 36 of introducer hub 31 along a circumference and extend radially from bore 35.
In a preferred embodiment, the rotational securement means comprises protuberances 29 and recesses 39 which are complementary and sized and spaced so that when protuberances 29 are brought into contact with the recesses 39 as a result of rotational engagement of threads 27 and 37, protuberances 29 drop into, and become seated within, recesses 39 so that an interference fit results thereby inhibiting accidental rotational disengagement. In a further preferred embodiment, protuberances 29 and recesses 39 are semi-cylindrical in shape. In a more preferred embodiment, two semi-cylindrical protuberances are spaced equally on the planar distal surface 26 of dilator hub 21 along a diameter through the bore of the hub and two complementary semi-cylindrical recesses are spaced equally on the planar proximal surface 36 of introducer hub 31 along a diameter through bore 35.
In an alternative embodiment, the rotational securement means comprises at least one protuberance 29 disposed on the proximal planar surface 36 of introducer hub 31 on a radius from the bore 35 and at least one complementary recess 39 disposed on the distal planar surface 26 of dilator hub 21 on a radius from the bore of hub 21. In a further alternative embodiment, at least one protuberance 29 and at least one recess 39 are disposed on the proximal planar surface 36 of introducer hub 31 and a corresponding number of complementary protuberances 29 and recesses 39 are disposed on the distal planar surface of dilator hub 21.
In another alternative embodiment, the rotational securement means comprises a plurality of threads 27 and 37 sized and spaced so that when threads are rotationally engaged an interference fit between threads 27 and 37 results inhibiting accidental rotational, as well as axial, disengagement of the first and second catheter element hubs. In a further alternative embodiment, the rotational securement means comprises the planar distal surface 26 of dilator hub 21 and the planar proximal surface 36 of introducer hub 31 treated or coated in such a manner so that when distal planar surface 26 and proximal planar surface 36 are brought into contact as a result of rotational engagement of threads 27 and 37, a friction fit results thereby inhibiting accidental rotational disengagement of the first and second catheter element hubs.
In a preferred embodiment, dilator hub 21 and introducer hub 31 may be engaged by bringing threads 27 into contact with threads 37 disposed on the inner surface of the proximal end of introducer bore 35 and rotating dilator hub 21 until threads 27 rotatably engage threads 37. As dilator hub 21 is further rotated so as to more completely rotatably engage threads 27 and 37, protuberances 29 and recesses 39 both axially and rotationally approach and eventually become aligned. Before protuberances 29 come into alignment with recesses 39 as a result of the rotational engagement of threads 27 and 37, protuberances 29 come in contact with the proximal planar surface 36 of introducer hub 31. This increases the resistance to further engagement of threads 27 and 37 and requires an increased torque to overcome the increased resistance. When protuberances 29 drop into, and become seated within, recesses 39 the increased resistance is eliminated and the user is provided with the sense that dilator hub 21 and introducer hub 31 are engaged. When protuberances 29 are seated within recesses 39, an interference fit results. Once protuberances 29 are seated within recesses 39, further rotation is precluded by the combination of the engagement of threads 27 and 37 and the resistance resulting from the interference fit between protuberances 29 and recesses 39.
When threads 27 and 37 are completely engaged, accidental axial disengagement of dilator hub 21 from introducer hub 31 is prevented. Additionally, when protuberances 29 are seated within recesses 39, accidental rotational disengagement is inhibited. When threads 27 and 37 are completely engaged and protuberances 29 are seated within recesses 39, dilator hub 21 and introducer hub 31 can not begin to be axially or rotationally disengaged until the resistance resulting from protuberances 29 being seated within recesses 39 is first overcome. The user in overcoming the resistance resulting from the protuberances 29 being seated in recesses 39 is provided with the sense that the dilator hub 21 and introducer hub 31 are disengaged.
The location of threads 27 and 37, protuberances 29 and recesses 39 allow for a catheter assembly having a lower profile as a result of the reduction in the distance between the proximal surface 36 of introducer hub 31 and hemostasis gasket 38.
Having described the invention in specific detail and exemplified the manner in which it may be carried into practice, it will now be readily apparent to those skilled in the art that innumerable variations, applications, modifications and extensions of the basic principles involved may be made without departing from its scope. | A catheter assembly comprising two elements each having a hub disposed at the proximal end thereof. The hubs are constructed so as to be complementary and rotatably engageable as the result of a plurality of threads disposed on the hubs of the two catheter introducer elements. When the threads of the hubs of the two catheter elements are engaged axial disengagement of the hubs is inhibited. The catheter assembly also comprising a means of securing against accidental rotational disengagement. The size and location of the threads and the rotational securement means permits the catheter assembly to have a lower profile because the distance to the hemostasis gasket is reduced thus permitting easier access to the hemostasis gasket. | 8 |
BACKGROUND OF THE INVENTION
The present invention relates to an ignition timing control apparatus for gasoline engines, etc., and more particularly to an ignition timing control apparatus having a knock control function.
With gasoline engines, etc., attempts to enhance their performance often lead to many detrimental effects due to engine knocking.
Thus, devices of the type employing a sensor for detecting knocking so that upon occurrence of knocking the ignition timing is immediately retarded to prevent the knocking, that is, so-called knock control devices, have recently come into wide use.
With the known type of knock control devices, when knocking occurs, the ignition timing is retarded a predetermined amount and then the ignition timing is gradually restored to the basic ignition timing providing the same amount of ignition timing retard for all the cylinders of the engine (e.g., Japanese Patent Unexamined Publication No. 57-38667).
Also, with gasoline engines, etc., the knocking ignition timing differs considerably among the cylinders depending on the engine with the result that in the case of the known knock control device, despite the knock control being performed, the cylinders having a high knocking tendency always cause knocking.
Assuming now that the basic ignition timing is set in relation to the cylinder having the highest knocking tendency, it is impossible to ensure a satisfactory engine performance. On the other hand, if the basic ignition timing is set in relation to the cylinder having the lowest knocking tendency, the cylinders having the higher knocking tendency always remain in the knocking zone so that these cylinders always cause middle or heavy knocking during the interval between the time that the ignition timing is retarded and the time that the ignition timing is restored to the basic ignition timing. Note that the terms middle knock and heavy knock indicate degrees of knocking, that is, middle knock designates a medium degree of knocking and heavy knock designates a considerably high degree of knocking. Also, a light degree of knocking is called light knock and a very low degree of knocking is referred to as a trace knock.
Thus, the conventional knock control devices are disadvantageous in that the variations in knocking characteristics among the cylinders are not accommodated and the desired engine performance is not ensured fully.
This type of knock control device is disclosed for example in Japanese Patent Unexamined Publication No. 58-167880.
The known knock control devices are also disadvantageous in that, if there are variations in knock intensity among the cylinders of an engine, there is the danger of failing to detect knocking with respect to some cylinders and thus a failure to satisfactorily prevent the occurrence of knocking. Moreover, the engine and sensor undergo aging so that it has been difficult in the past to ensure satisfactory detection of knocking and hence prevent the occurrence of knocking.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide an ignition timing control apparatus for an internal combustion engine which overcomes the foregoing deficiencies in the prior art and is capable of always ensuring satisfactory engine performance and satisfactorily preventing the occurrence of knocking even if there are variations in knocking characteristics among the cylinders of an engine.
It is another object of the invention to provide an ignition timing control apparatus for an internal combustion engine which is capable of always detecting the occurrence of knocking positively and of preventing the occurrence of knocking satisfactorily irrespective of the variations in knocking characteristics among the engine cylinders and the aging of the sensor.
To accomplish the first object, in accordance with the invention the basic ignition timing of each cylinder is controlled in response to the knocking conditions in each cylinder.
To accomplish the second object, in accordance with the invention the level of a detection signal corresponding to the detection of knocking with no ignition timing retard is compared with the level of a detection signal generated at the retarded ignition timing so that when the level of the latter is higher than the former, the knock detection level is corrected.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block diagram showing an embodiment of an ignition timing control apparatus according to the invention.
FIG. 2 is a block diagram showing an embodiment of the input/output interface according to the invention.
FIG. 3 is a time chart for explaining the operation of the invention.
FIG. 4 is a block diagram showing an embodiment of the knock detecting device.
FIG. 5 illustrates a plurality of signal waveforms useful for explaining the operation of the knock detecting device.
FIG. 6 is a general flow chart for the embodiment of the invention.
FIG. 7 is a diagram showing an ignition timing control routine.
FIG. 8 is a diagram showing a rotation synchronization routine.
FIG. 9 is a timing chart for explaining the operation of the first embodiment of the invention.
FIG. 10 is a diagram for explaining the operating regions according to the first embodiment of the engine.
FIG. 11 is a block diagram showing another embodiment of the knock detecting device.
FIG. 12 illustrates a plurality of signal waveforms useful for explaining the operation of the knock detecting device of FIG. 11.
FIG. 13 is a flow chart showing an example of a rotation synchronization processing routine.
FIG. 14 is a block diagram showing another embodiment of the knock detecting device.
FIG. 15 is a circuit diagram showing an embodiment of the integration peak hold circuit.
FIG. 16 illustrates a plurality of signal waveforms for explaining the operation of the knock detecting device of FIG. 11.
FIG. 17 is a flow chart showing another example of the rotation synchronization processing routine.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
An ignition timing control apparatus for an internal combustion engine according to the invention will now be described in detail with reference to the illustrated embodiments.
Referring to FIG. 1 illustrating an embodiment of the invention, a central processing unit or CPU 12 performs digital computations of various data such as the ignition timing of the engine. A ROM 14 stores an ignition timing control program and fixed data. A RAM 16 is a read/write memory device. A back-up RAM 17 is a RAM for holding the data even when the engine is stopped.
The CPU 12 receives a signal from each of various sensors (this embodiment uses a knock detecting device 30, a crank angle sensor 40, a load sensor 50, a water temperature sensor 60 and a load switch 80) through an input/output interface circuit 20, so that in accordance with the program stored in the ROM 14 an ignition timing is computed on the basis of these signals and the ignition signal IGN is generated through the input/output interface circuit 20. The ignition signal IGN is applied to a base 70 of a power transistor 74 through an amplifier 72 and the power transistor 74 is turned on. When the power transistor 74 is turned off, an ignition current is produced in the secondary winding of an ignition coil 76.
FIG. 2 shows a detailed construction of a portion of the input/output interface circuit 20 operatively associated with the ignition timing control.
The crank angle sensor 40 applies position pulse signals POS to AND circuits 216 and 220. The crank angle sensor 40 also applies a reference crank angle signal REF to the reset terminal of a first counter register 210 and the set terminal of an R-S flip-flop 218. The first counter register 210 is responsive to the leading edge of the signal REF to start counting the signals POS through the AND circuit 216 and the R-S flip-flop 218 and the resulting count is applied to a comparator 206. The comparator 206 compares the count of the first counter register 210 and the ignition timing data θ ig computed by the CPU 12 and stored in an advance register 202, so that when the two are equal, a set pulse is applied to an R-S flip-flop 214 and the R-S flip-flop 218 is reset. When the set pulse is applied to the R-S flip-flop 214, its Q output is interrupted and the ignition power transistor 74 is turned off thus supplying a discharge current to the secondary winding of the ignition coil 76.
The timing of starting current supply to the ignition coil 76 will now be described.
In response to the set pulse generated from the comparator 206 to set an R-S flip-flop 222, a second counter register 212 starts the counting of position pulses POS through the AND circuit 220 and the resulting count is applied to a comparator 208. The comparator 208 compares this count and the value computed by the CPU 12 and stored in a dwell register 204 so that when the two are equal, a reset pulse is applied to the R-S flip-flop 214 and the R-S flip-flop 222 is reset. In response to the reset pulse, the R-S flip-flop 214 generates an output at its Q terminal so that the power transistor 74 is turned on and the flow of current to the primary winding of the ignition coil 76 is started.
Next, the introduction of a knock signal KNCKP into the CPU 12 will be described.
The knock signal KNCKP generated from the knock detecting device 30 is applied to a counter register 234 and a number of knock pulses proportional to the intensity of the knock produced are counted. The CPU 12 receives the count of the counter register 234 through a bus 18.
The pulse count NP thus applied to the CPU 12 is the data corresponding to the knock intensity and it is used for the computation of an ignition timing correction amount.
FIG. 3 is a timing chart showing the operation of the above-mentioned circuits of FIG. 2. In FIG. 3, (A) shows a reference crank angle signal, (B) a position pulse signal, (C) the count of the first counter register 210, and C 1 the preset value in the advance register 202. (D) shows the output signal of the comparator 206 which is generated when the count of the first counter register 210 attains the preset value in the advance register 202. (E) shows the count of the second counter register 212, and (E 1 ) the preset value in the dwell register 204. (F) shows the output of the comparator 208 which is the same in operation with the comparator 206, and (G) the Q output of the R-S flip-flop 214 which is responsive to the outputs of the comparators 206 and 208 or the signals D and F. (H) shows the current in the ignition coil 76 which is supplied in response to the Q output, and (I) the ignition timing.
Referring now to FIG. 4, there is illustrated a block diagram of the knock detecting device 30 which is responsive to the occurrence of knocking to generate a number of pulses corresponding to the intensity of the knock. In the Figure, a knock sensor 401 comprises a piezoelectric element to convert the knocking vibrations of the engine cylinder to an electric signal. The output signal V IN of the knock sensor 401 is applied to a band-pass filter 403 through an input processing circuit 402. The band-pass filter 403 is provided to remove the parasitic oscillations of the engine and efficiently take out a knock signal and its band width is selected to correspond with those frequencies at which a knock signal is generated.
The knock signal passed through the band-pass filter 403 is first half-wave rectified by a half-wave rectifier circuit 404 and then it is branched into two paths. Thus, on the one hand, the signal is amplified as a knock representative signal by a dc amplifier circuit 405, and on the other hand is amplified as a discrimination level for knock detection by a dc amplifier circuit 407 after it has been smoothed by a smoothing circuit 406. A comparator 409 compares the two signals so that a knock detection signal is generated and applied to an I/O circuit 410.
FIG. 5 shows the signal waveforms generated at various points in the block diagram shown in FIG. 4. (1) shows the output waveform of the knock sensor 401, (2) the output waveform of the input processing circuit 402, (3) the output waveform of the band-pass filter 403, (4) the output waveform of the half-wave rectifier circuit 404, (5) the output waveform of the amplifier circuit 405, (6) the output waveform of the smoothing circuit 406, (7) the output waveform of the amplifier circuit 407, and (8) the knock detection signal KNCKP or the output waveform of the comparator 409.
FIG. 6 shows a general flow chart of the ignition timing control apparatus according to the present embodiment.
In the Figure, when an interrupt request 600 is generated, whether it is a reference (REF) or timer interrupt is determined by the interrupt request analytic processing of the next step 602. If it is the timer interrupt (TIMER), tasks including an input signal A/D conversion and engine speed inputting task (606), a basic ignition timing and dwell time computing task (608) a digital input signal processing task (610) and a correction task (612) are performed.
FIG. 7 shows an ignition timing and dwell time control routine corresponding to the step 608 in FIG. 6 and this routine computes a basic ignition timing θ ADV (base) from an equation θ ADV (base)=f (N, L). Here, N represents the engine speed and L the engine load (e.g., the intake manifold vacuum).
First a basic ignition timing processing is performed at steps 701 and 702. At a step 703, the counter data for advancing after the ignition retard is determined. If the counter content is zero, it is determined that a given period of time (e.g., a second) has elapsed and a transfer is made to a step 706. Thus, an advancing data Δθ ADV2 is set at the step 706. Then, since the given time has elapsed, a lapse of given time confirming data is set in the counter at a step 707 and a transfer is made to a step 708.
On the contrary, if the counter data is not zero at the step 703, it is an indication that the given time has not elapsed and the advance data Δθ ADV2 is set to 0. This is done at a step 704. At a step 705, the counter data is decreased by 1 so as to measure the passage of time. Then, a transfer is made to the step 708.
FIG. 8 shows a rotation synchronization processing routine corresponding to a step 616 of FIG. 6.
At a step 801, the counter date (the number of pulses NP) is inputted. After the inputting, the counter is cleared. At a step 802, the corresponding cylinder is discriminated and the knock discrimination level (the number of pulses) corresponding to the current cylinder is searched. This discrimination level is a function of the engine speed and load. At a step 803, the counter data NP and the searched knock discrimination level N SI are compared. This discrimination level N SI is used for performing the ordinary ignition timing control. If the counter data NP is greater than the discrimination level N SI , the presence of knocking is determined and a transfer is made to a step 804 thereby retarding the ignition timing. Here, Δθ ADV1 represents the current correction amount and Δθ ADV (t-1) represents the preceding correction amount (the amount of retard).
At a step 805, in accordance with the current engine speed N and load L, corresponding one of the regions shown in FIG. 10 (while the four regions are provided in accordance with the engine speeds N and loads L, they may be provided in accordance with only the speeds or the loads and alternatively a greater number of regions may be provided) is discriminated and a maximum advance angle determining data α 1 is searched. At a step 806, the value NP of the counter is compared with a discrimination level N S2 for controlling the maximum advance angle. If the value of NP is greater than N S2 at the step 806, it is determined that the current knock condition is middle knock and a computation of α 1 (t)=α 1 (t-1)+α 1 for correcting the maximum advance angle (the maximum value of the advance after the ignition retard) is performed at a step 807. Also, when the counter value NP is smaller than N S2 at the step 806, it is predetermined that the maximum advance angle need not be corrected and the previous value is used as α 1 (t)=α 1 (t-1). Then, a transfer is made to a step 809. The step 809 sets in the advance counter the data for advancing after the ignition timing has been retarded upon the occurrence of knocking (in this embodiment data corresponding to 1 second is set). Note that the counter is operated by a TIMER interrupt to determine whether a predetermined time has elapsed. Then, a transfer is made to a step 811.
On the other hand, if the step 803 determines that NP<N S1 , the absence of knock is determined and a transfer is made to a step 810. The step 810 performs the ignition advance after the retard. However, since the data Δθ ADV2 is set to 0 at the step 704 if the predetermined time (1 second) has not elapsed, no ignition advance is made and the data Δθ ADV (t) assumes the previous value.
θ.sub.ADV (t)=θ.sub.ADV (base)+Δθ.sub.ADV (t)
At a step 811, the basic ignition timing θ ADV (base) and the ignition timing correction amount are added up and thus the ignition timing θ ADV (t) is determined.
At a step 812, the current operating region (FIG. 10) is searched and the maximum advance angle correction amount α 1 (t) corresponding to the region is obtained.
At a step 813, the maximum advance angle θ max is controlled in accordance with the current basic ignition timing θ ADV (base) and the correction amount α 1 (t), as follows
θ.sub.max =θ.sub.ADV (base)-α.sub.1 (t).
At a step 814, the maximum advance angle θ max and the current ignition timing θ ADV (t) are compared. If the step 814 determines that θ max <θ ADV (t), a transfer is made to a step 815 and the maximum advance angle is set to θ max . If the step 814 determines that θ max <θ ADV (t), the current ignition timing still leaves margine for further advance and the current value is set in the ADV register at a step 816. As the result of the foregoing control, the advance angle after the retard is controlled at θ max at the most. If there is no occurrence of knocking, the ignition timing for this cylinder is maintained at θ max so that the basic ignition timing is controlled as shown by the following equation
θ.sub.max =θ.sub.ADV (base)-α.sub.1 (t)
As described hereinabove, the above basic ignition timing is corrected for each cylinder and this prevents the frequent occurrence of middle knock.
Referring to FIG. 9 showing a timing chart for explaining the operation of this embodiment, if middle knock occurs at ○A in one cylinder operating at the basic ignition timing θ ADV (base) (when NP of the step 801 of FIG. 8 is NP>N S2 ), the ignition timing is retarded by Δθ ADV1 so that if the knocking no longer occurs, the ignition timing is advanced at the rate of Δθ ADV2 per Δt (1 second). At this time the advance angle is controlled at θ ADV (base)-α 1 in accordance with θ max =θ ADV (base)-α 1 (t).
If middle knock occurs at ○B in the same cylinder in the same operating region, the advance angle is controlled at θ max =θ ADV (base)-2α 1 .
If middle knock occurs at ○C , the maximum advance angle is controlled at the following
θ.sub.max =θ.sub.ADV (base)-3α.sub.1
At this time, if trace knock occurs at ○D , the ignition timing is first retarded by Δθ ADV1 and then advanced at the rate of Δθ ADV2 per Δt (1 second) until finally attaining θ max =θ ADV (base)-3α 1 . In other words, this means that in this operating region, the basic ignition timing of this cylinder is changed to θ ADV (base)-3α 1 and the knocking is reduced to a suitable level.
This control is performed in the same manner on the ignition timing of the remaining cylinders. Thus, in accordance with this embodiment, the desired retard control of the basic ignition timing is provided for each cylinder in accordance with the occurrence of knocking in the cylinder thus enhancing the engine performance to the utmost extent while satisfactorily reducing the ill effects of knocking.
As described hereinabove, in accordance with the invention, by virtue of the fact that the desired corrective control of the basic ignition timing is provided for each cylinder in accordance with the occurrence of knocking in the cylinder, there is easily provided an ignition timing control apparatus which overcomes the deficiencies in the prior art and is capable of always accurately providing the desired retard control of the ignition timing in accordance with the occurrence of knocking in each cylinder and ensuring full advantage of the engine performance.
Referring to FIG. 11 showing another embodiment of the invention, there is illustrated a block diagram of a knock detecting device 30 which generates a number of pulses corresponding to the intensity of the knocking. In the Figure, a knock sensor 401 converts vibrations of the engine to an electric signal. The knock sensor 401 applies its output signal V IN to a band-pass filter 403 through an input processing circuit 402. The band-pass filter 403 is provided to remove the parasitic oscillations of the engine and efficiently generate a knock signal and its band width is selected to correspond with those frequencies at which a knock signal is generated.
The knock signal passed through the band-pass filter 403 is half-wave rectified by a half-wave rectifier circuit 404 and it is then branched into two paths. Thus, on the one hand, the signal is amplified as a knock representative signal by a dc amplifier 405, while on the other hand, the signal is smoothed by a smoothing circuit 406 and then amplified by a dc amplifier circuit 407 to provide a discrimination level for knock detecting purposes. A comparator 409 compares the signals from the two paths so that a knock detection signal is generated and applied to an I/O unit 410. The output of the comparator 409 is applied to the I/O unit 410 at a specified timing (more particularly, at 10 to 70 degrees ATDC).
The operation of this embodiment will now be described with reference to FIGS. 12 and 13. Note that this embodiment is applied to a four cylinder engine.
Shown in (1) of FIG. 12 are the engine cylinder numbers. More specifically, numeral 1 designates the No. 1 cylinder and numeral 3 designates the No. 3 cylinder (the same applies similarly to the following). Shown in (2) are waveforms at the same points as in (5) of FIG. 5, and (3) the output of the comparator 409 as in (8) of FIG. 5 Shown in (4) is the ignition timing of the No. 4 cylinder. In other words, a condition is shown in which the ignition timing is retarded by θ K at a point K in response to the occurrence of knocking in the No. 4 cylinder. Noting the No. 4 cylinder alone, the detected value at the time of the occurrence of knocking is 4 (the point C) and the detected value upon retarding of the ignition timing is 2 (the point G). This shows that the occurrence of knocking is eliminated by the retarding of the ignition timing. In this case, if the detected value at the point G is not 2 but 5, for example, this detected value is not due to the occurrence of knocking but is due to some other cause such as noise and thus the detection level is corrected. This is the principle.
The correction of the knock detection level will now be described with reference to the flow chart of FIG. 13.
At a step 701, the output of the comparator 409 of FIG. 11 is inputted. While the output is a number of pulses in the case of FIG. 11, it may take any other form than a number of pulses, e.g., a voltage. With the output (KCNT) k , n at the step 701, k and n indicate the nth ignition of the No. k cylinder. At a step 702, the detected value (KCNT) k , n at the nth ignition of the No. k cylinder is compared with the knock detection level K SL of the No. k cylinder. The knock detection level K SL is the sum of the basic detection level K I (more specifically K I =3) and the knock detection level correction amount at the nth ignition of the No. k cylinder as follows
K.sub.SL =K.sub.I +α.sub.k, n
If the result of the comparison at the step 702 shows that (KCNT) k , n ≦K SL , it is determined that there is no occurrence of knocking and a transfer is made to a step 703. The step 703 computes the average value of M detected values of the No. k cylinder (more specifically M=16). Thus, the computed value of the step 703 is used as the next knock detection level correction amount α k , n+1 of the No. k cylinder. If the result of the step 702 shows that (KCNT) k , n >K SL , the occurrence of knocking is determined and a transfer is made to a step 704. The step 704 determines whether the current operating condition is an acceleration. If the result of the determination shows that the engine is accelerating, a transfer is made to a step 708. The step 708 computes the average value of M detected values KCNT and it is set as a correction amount α k , n+1. Thus, the knock detection level correction amount is renewed. After the completion of the step 708, a transfer is made to a step 709.
On the other hand, if the determination of the step 704 shows that the engine is not accelerating, a transfer is made to a step 705. The step 705 compares the preceding (the (n-1)th ignition) detected value (KCNT) k , n-1 (upon the occurrence of knocking) and the current detected value (KCNT) k ,n (upon the ignition timing retard) of the No. k cylinder. If the result of the comparison shows that (KCNT) k , n-1 ≧(KCNT) k , n, a transfer is made to a step 707 so that the current value is used as the knock detection correction amount α for the (n+1)th ignition. After the completion of the step 707, a transfer is made to the step 709.
If the result of the step 705 shows that (KCNT) k , n- 1<(KCNT) k , n, it is an indication that the detected value has increased despite the ignition timing retard and thus the detection level correction amount α is corrected. At a step 706, the sum of the current detected value (KCNT) k , n and a correction amount k 2 is set as the correction amount α k , n+1.
Thus, in accordance with this embodiment, the knock detection level correction amount α is corrected by each knock detected value and hence the knock detection level K SL is corrected (K SL =α+K 1 ). This has the effect of overcoming the variations in knocking among the cylinders and the effects of their aging thereby always maintaining the proper detection level and ensuring the positive detection of knock.
Referring now to the block diagram of FIG. 14 showing another embodiment of the knock detecting device, a gate 412 controls the input to a peak hold circuit 413 and it serves the function of applying to the peak hold circuit 413 the output of a half-wave rectifier 404 which is generated at 10 to 70 degrees ATDC. The peak hold circuit 413 applies its output to the A/D converter in the I/O unit 20. A reset circuit 414 serves the function of reseting the peak hold circuit 413.
Referring now to FIG. 15, there is illustrated a specific embodiment of the peak hold circuit 413.
The peak hold circuit 413 comprises capacitors 451 and 458, diodes 452 and 455, resistors 453, 454, 456, 457, 459 and 461, a transistor 460, an operational amplifier 462 and an operational amplifier 463 forming a buffer circuit.
The capacitor 451 and the diode 452 convert the half-wave rectified signal to a waveform which is positive with respect to the ground level (actually more positive than -V F of the diode 452) and this waveform charges the capacitor 458. When the peak hold circuit 413 is reset, the transistor 460 is turned on through the resistor 461 and the charged voltage across the capacitor 458 is discharged through the resistor 459.
Referring now to FIG. 16 showing various waveforms for explaining the operation of the knock detecting device, in (1) of the Figure the numerals show the cylinder numbers and shown in (2) is the half-wave rectified output. Also, shown in (3) of the Figure is the input to the A/D converter (the output of the operational amplifier 463). Designated by V An1 is the A/D converter input at the time of the nth ignition of the No. 1 cylinder.
Referring now to the flow chart of FIG. 17, at a step 802, the inputted A/D converted value V An1 for the nth ignition of the No. k cylinder is compared with the knock detection level V SL to make a decision as to the presence of knocking. If V An1 ≧V SL , the presence of knocking is determined. If V An1 <V SL , the absence of knocking is determined.
After the presence of knocking has been determined, at a step 805, a comparison is made between the A/D converted value V Ak , n-1 at the time of occurrence of knocking and the A/D converted value V Ak , n after the ignition timing retard. If V Ak , n-1 <V Ak , n, the next knock detection level V BGL , n+1 is changed to V Ak , n+Q (a step 806).
If V Ak , n-1 >V Ak , n, the current knock detection level V BGLk , n is used as the next knock detection level V BGLk , n+1 (a step 807).
In the case of the absence of knocking, the knock detection level is corrected to the average value of 16 A/D converted values. In other words, it is corrected as follows (a step 803). ##EQU1## Then, the thus corrected V BGLk , n is used for the next (n+1)th ignition.
In the case of the presence of knocking, if the engine is accelerating, the knock detection level is also corrected as follows (a step 808) ##EQU2## This knock detection level is used for the next (n+1)th ignition and then the processing proceeds to the knock control.
Thus, in accordance with the present embodiment, the knock detection level is always corrected to the proper value and the accurate detection of knocking is always ensured irrespective of the variations in knocking characteristics among the cylinders and changes in the characteristics of the sensor.
From the foregoing description it will be seen that in accordance with the present invention, by virtue of the fact that the level of knock detection on the basis of a knock detection signal is successively corrected to the proper value, there is provided an ignition timing control apparatus for an internal combustion engine which overcomes the deficiencies in the prior art and is capable of always accurately detecting the occurrence of knocking and performing the proper knock control irrespective of the variations in knocking characteristics among the engine cylinders and the aging of the knock sensor thus ensuring the desired engine performance. | An ignition timing control apparatus for an internal combustion engine having a plurality of cylinders. The apparatus includes a knock sensor for detecting a knocking condition in the engine, sensors for detecting other operating conditions of the engine, a microprocessor unit for receiving signals from the sensors to determine a basic ignition timing of the engine and generate an ignition timing control signal, and a power transistor circuit responsive to the ignition timing control signal from the microprocessor unit to switch on and off the primary current in an ignition coil and generate a high-voltage ignition signal. The microprocessor unit has a control function of retarding the basic ignition timing a predetermined amount in response to a knock detected during an ignition operation at the basic ignition timing and another control function of gradually restoring the retarded ignition timing to the basic ignition timing in response to a knock detected during an ignition operation at the retarded ignition timing from the basic ignition timing. The apparatus includes control means responsive to the occurrence of a knock to correct the basic ignition timing for each cylinder of the engine whereby the basic ignition timing of each cylinder is controlled to be retarded in response to the detection of a knock in each cylinder. | 5 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to solvent pumps which are used to pump adhesives to a site where bonding of two components can occur. The solvent can be used in conjunction with mass production apparatus which requires a minute quantity of such solvent to be delivered to the adhesion cite on a precisely timed repetitive basis.
2. Description of the Prior Art
In general, solvent metering pumps are known in the prior art. An illustration of one specific type of solvent pump which illustrates principles of prior art pumps is shown in FIG. 1 and is marked "PRIOR ART". This type of pump is manufactured by Valcor Engineering Corp. and is commonly known as a solenoid metering pump. A cross-sectional view of this type of pump is shown in FIG. 1. The pump 300 has a piston 302 which is pulled upward when a solenoid coil 304 is electrically energized. When the solenoid coil 304 is deenergized, a return spring 306 causes the piston 302 to move downwardly and return to its at rest position. The piston 302 moves inside a tube 310. The lower end of the tube 310 is enlarged to form a cylindrical chamber 312. The lower end of the piston 302 is enlarged to form a piston head 303. The piston head 303 divides the chamber 312 into an upper chamber 314 and a lower chamber 316. The piston head 303 contains a groove 305. A torroidal elastomeric pump ring 318 is contained in the groove 305.
When the solenoid coil 304 is energized the piston 302 is pulled upward. This in turn enables the pump ring 318 to form a seal between the piston head 303 and the wall of chamber 312. Fluid such as solvent 320 located in the upper chamber portion 314 is forced through the tube 310 and through outlet 322. At the same time, an inlet poppet check valve 324 is opened and solvent 320 is drawn into the lower chamber portion 316 through inlet 326. When the solenoid coil 304 is de-energized so that the return spring 306 forces the piston 302 back to its at rest position, the poppet check valve 324 closes by means of return spring 328 and solvent 320 is forced from the lower chamber portion 316 into the upper chamber portion 314 through a longitudinal slot 307 in the piston 302. The amount of solvent pumped during each cycle depends on the piston stroke length which can be manually adjusted.
In principal, most prior art metering pumps work along the principles of the illustrative example set forth above. The prior art works well for applications of solvent which is primarily in pure liquid form and does not contain any solid particulates. The prior art metering pumps do not work properly when they are required to pump solvents containing solid particulate adhesive matter due to the incorporation of check valves in the prior art designs. The solid particulate matter adheres to portions of the valve or valve seat, thereby interfering with proper opening and closing of the check valve assembly.This creates many problems in the operation of the pump. Since the check valve cannot close properly, there is additional pressure for excess fluid or solvent attempting to enter the pump from the major fluid or solvent reservoir. Since the adhesive causes the check valve to open improperly, insufficient fluid may be delivered through the pump. In addition, the improperly operating check valve may cause the timing of the entire pump to be off its set delivery timing and therefore solvent may be delivered to a site at an improper moment. While the check valve assembly has been illustrated in one position in the example set forth above, other metering pumps may have one or more such check valves at different locations throughout the pump. When solvent containing solid particulates comes in contact with one or more of such check valves, one or more of the problems set forth above will occur, thereby substantially interfering with the operation of the pump. Since such pumps are used on mass production machines which require the solvent to be delivered to a particular bonding site at a precise time during many repetitive cycles performed at high speeds, a problem can occur and not be noticed by the operator until substantial damage has been done to the pump, to parts of the assembly machine with which the pump is associated and to numerous parts being bonded together during the assembly operation.
There is no presently available metering pump which efficiently delivers solvent containing solid particulate matter for applications of use during a precise timing cycle requiring many rapid repetitions.
SUMMARY OF THE PRESENT INVENTION
The present invention relates to a novel solvent pump which can deliver precise quantities of solvent containing solid particulate matter to a precise location at a prescribed precise series of timing cycles requiring many rapid repetitions. The present invention is particularly useful for delivering precise quantities of cyclohexanone containing polyvinyl chloride particulates for purposes of providing the bonding solvent to bind polyvinyl tubing to objects used in conjunction with the tubing.
It has been discovered, according to the present invention, that if a solvent pump contains a solvent delivery apparatus which entirely eliminates the use of valves in the locations where the apparatus comes in direct contact with the solvent, then the solvent pump can be used to deliver quantities of solvent containing solid particulate matter without incurring problems associated with prior art solvent metering pumps.
It has also been discovered, according to the present invention that if solvent is delivered to the site of adhesion by means of moving a piston upwardly in a chamber containing the solvent and the piston is caused to move upwardly by external mechanical means, then check valves and other similar types of valves can be entirely eliminated from coming in contact with the solvent.
It has further been discovered, according to the present invention, that if the piston which delivers the force to cause the solvent to enter the required location is connected to external mechanical actuating means which causes the piston to move in one direction at precise timing intervals, then the novel solvent pump can deliver precise quantities of solvent containing solid particulate matter to a precise location at a prescribed precise series of timing cycles requiring many rapid repetitions.
It has additionally been discovered, according to the present invention, that if the mechanical actuating means incorporates into its structure an apparatus for providing a signal when the cylinder containing the solvent is almost empty, then the pump can be efficiently turned off by an operator so that the cylinder may be refilled with solvent without the necessity of expensive machine down time or the occurrence of parts being brought together without being properly bonded due to insufficient or a total lack of solvent being properly applied.
It is an object of the present invention to provide an apparatus for delivering precise quantities of solvent containing solid particulate matter as well as regular pure fluid solvent to a given location at a prescribed precise series of timing cycles requiring many rapid repetitions.
It is another object of the present invention to provide a solvent pump which can deliver precisely timed quantities of solvent containing solid particulate matter for use in conjunction with a mass production assembly machine.
It is a further object of the present invention to entirely eliminate the use of valves such as check valves from portions of a solvent metering pump which come in contact with the solvent.
It is an additional object of the present invention to provide a solvent metering pump which is operated by mechanical means in a simple and efficient manner to precisely deliver required quantities of solvent, to signal an operator when the pump is almost out of solvent, and to permit efficient refilling of the solvent pump without extensive down time or damage to the pump, to the assembly machine with which the pump is associated, or to products being assembled by the machine.
Further novel features and other objects of the present invention will become apparent from the following detailed description, discussion and the appended claims, taken in conjunction with the drawings.
DRAWING SUMMARY
Referring particularly to the drawings for the purpose of illustration only and not limitation, there is illustrated:
FIG. 1 is a cross-sectional view of a common PRIOR ART solvent metering pump.
FIG. 2 is a front view of the present invention.
FIG. 3 is a side view of the present invention with the solvent cylinder shown in cross-section.
FIG. 4 is a top plan view of the present invention, looking from the direction of arrows 4--4 in FIG. 2.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Although specific embodiments of the invention will now be described with reference to the drawings, it should be understood that such embodiments are by way of example only and merely illustrative of but a small number of the many possible specific embodiments which can represent applications of the principles of the invention. Various changes and modifications obvious to one skilled in the art to which the invention pertains are deemed to be within the spirit, scope and contemplation of the invention as further defined in the appended claims.
Referring to FIG. 2 and FIG. 3, the present invention Solvent Pump is shown at 10. The solvent pump 10 is housed on a mainframe member 12 which in turn consists of a base plate 14, a first side plate member 16, a second side plate member 18, a top plate member 20 and a clutch mounting plate member 22. As shown in FIG. 2, first side plate member 16 is supported on base plate 14 and extends perpendicularly thereto. The top of first side plate member 16 in turn supports first top plate member 20. First top plate member 20 is perpendicular to first side plate member 16 and generally parallel to base plate 14. As shown in FIG. 3, second side plate member 18 is also supported on base plate 14 and extends perpendicularly thereto. Second side plate member 18 in turn supports clutch mounting plate member 22 at a location below the top of the second side plate member 18. First side plate member 16 and second side plate member 18 are dipsosed perpendicular to each other and are attached to each other, thereby lending further mutual support. In the preferred embodiment, all components of the mainframe member 12 are made of metal such as stainless steel or aluminum.
First top plate member 20 contains a slotted opening 24. A solvent reservoir 26 rests on top of first top plate member 20 and is attached thereto by means of a first hollow coupling member 28. By way of example, the first hollow coupling member 28 can consist of a pipe member 30 and hexagonal pipe coupling nut 32 which is screwed onto the pipe member 30 and also screws onto a threaded opening 34 in the solvent reservoir 26. The first hollow coupling member 28 further comprises a first ball valve 36 which is opened and closed by means of first handle member 39. The first hollow coupling member 28 is in turn connected to a second hollow coupling member 40 by first tubing 42. Second hollow coupling member 40 can comprise a threaded pipe member 44 and a multiplicity of hexagonal coupling nuts . The tubing 42 is attached to first hollow coupling member 28 by coupling nut 46 and to second hollow coupling member 40 by coupling nut 48. The threaded pipe member 44 further comprises a 3-way ball valve 50. At its second end 52, the second hollow coupling member 40 is attached to the solvent ejection nozzle 53 (FIG. 3) which is placed at the location where the solvent is to be applied to the parts to be bonded together. The connection can be by means of tubing or comparable connecting means.
Spaced a short distance from the interior face 54 of first side plate member 16 is a hollow solvent cylinder 56. As shown in FIGS. 2 and 3, the solvent cylinder 56 is open at its top portion which leads into the hollow coupling member 40 adjacent the location of the 3-way ball valve 50 by conventional coupling means 64 such as a threaded pipe supported by nuts or threaded into the respective components. An internal channel (not shown) in the hollow coupling member 40 provides a passageway from the 3-way ball valve 50 to the hollow cylinder 56. As shown in the cross-sectional view of the cylinder 56 in FIG. 3, a piston 66 is located at the bottom of the cylinder 56 adjacent a support member 62 which supports the cylinder 56 on the internal wall 54 of first side plate member 16. The connection is made by the threaded bolt 58. The piston 66 comprises a head portion 68 and an extension portion 70. The head portion further comprises a circumferential groove 72 which houses an "O" ring sealing member 74 (or alternatively a cup seal sealing member, not shown) which by way of example can be made of teflon. The piston 66 is supported by piston rod 76 which at its upper end is inserted into the piston extension portion 70. The lower end of piston rod 76 is affixed to rod end coupling member 78. By way of example, rod end coupling member 78 can be a generally H-shaped piece of metal tubing with an upper face 80, a lower face 82, and a recessed mid-portion 84.
A pair of stationary support brackets 90 and 92 are affixed to second side plate member 18. The first such stationary support bracket 90 is located adjacent base plate 14 while the second stationary support bracket 92 is set at a distance above the base plate 14. The stationary support brackets 90 and 92 support a pair of stationary rods 94 and 96. A movable slide member 98 is movably attached to the pair of stationary rods 94 and 96 through channels (not shown) which extend through the length of the slide member 98. The movable slide member 98 is affixed to an angle bracket member 98 which comprises a vertical portion 102 attached to the movable slide member 98 and a horizontal portion 104 extending perpendicularly thereto. The horizontal portion 104 of the angle bracket member 100 contains a transverse opening 106.
Movably inserted through the transverse opening 106 is a T-shaped lead nut 108 which contains an internally threaded shaft 110. The horizontal portion 112 of the T-shaped lead nut presses against the lower surface of the horizontal portion 104 of angle bracket member 100 while the vertical portion 114 of the T-shaped lead nut extends through the opening 106. Securing means such as a cap screw 115 extends through an internal threaded passage 113 in the side of the horizontal portion 104 of angle bracket member 100. When in the fully tightened position, the cap screw 115 abuts the vertical portion 114 of T-shaped nut 108 and causes the angle bracket 100 and T-shaped nut to move together. When the cap screw 115 is loosened, the T-shaped nut 108 can move independently of the angle bracket 100. At the opposite side, the horizontal portion 104 of angle bracket 100 is joined with rod end coupling member 78 such that the horizontal portion 104 abuts the recessed mid-portion 84 of the rod end coupling member 78 and is sandwiched between its upper face 80 and its lower face 82.
Threaded through the internally threaded shaft 110 of T-shaped nut 108 is a threaded rod 116. The threaded rod 116 is rotatably supported at its lower end by the T-shaped nut 108 adjacent base plate 14 so that it extend transversely thereto and parallel to the piston rod 76. Clutch mounting plate 22 contains a transverse opening 118 to permit the upper portion of the threaded rod 116 to pass therethrough. Attached adjacent the upper portion of threaded rod 116 and movably supported by the clutch mounting plate 22 is a first one-way clutch 120. Attached at the top of the threaded rod 116 is a second one-way clutch 122. Both one way clutches permit the threaded rod 116 to rotate in the same direction. Attached to the lower extremity of the second one-way clutch 122 is a movable lever arm assembly 124 which comprises a base portion 126 attached to the second one-way clutch 122 through base portion opening 117, and to the threaded rod 116 and an arm portion 128 extending in a direction generally parallel to the base plate 14 and toward first side plate member 16 (see FIG. 4). First side plate member 16 contains a slotted opening 17 to permit the arm portion 128 to pass therethrough and to move in a horizontal direction within the first side plate member 16. The rear face of first side plate member 16 contains a spring support member 130 which supports a return spring means 132 through opening 134. Return spring means 132 is movably inserted into an opening 135 adjacent the tip of arm portion 128. Attached to the arm portion 128 at a location adjacent the front face of the first side plate member is a stop block 136. On either side of the arm portion 128 adjacent the first side plate member 16 at the location of the stop block 136 are a pair of adjustable arm stopping means. First adjustable arm stopping means 138 is supported on second side plate member 18 and extends toward the arm portion 128 and stop block 136. Second adjustable arm stopping means 140 is supported by spring support member 130 on first side plate member 16 and extends towards arm portion 128 and stop block 136 in the direction opposite to the first adjustable arm stopping means 138. By way of example, first and second adjustable arm stopping means can be threaded shafts and this distance between the tip of each shaft and the stop block 136 can be varied by rotating each respective shaft in the appropriate direction.
Attached to the front or internal face of the second side plate member 18 is an air cylinder 142 with a movable tip 144 aligned withe arm portion 128 of the movable lever arm assembly. Located adjacent the outer face of second side plate member 18 is a directional air valve 146 which is triggered by an electrical start means 148. An air intake connecting means such as a first length of tubing 150 and an air exhaust connecting means such as a second length of tubing 152 connect the directional air valve 146 to the air cylinder 142.
Located on the rear or outer face 19 of second side plate member 18 is signalling means 154. The signalling means 154 further comprises an activating switch 156 located on its lower extremity. Second side plate member 18 further comprises an elongated vertically disposed internal slot 160 extending from adjacent base plate 14 to adjacent the activating switch 156 on signalling means 154. A button or switch activating member 158 is attached to the rear face of the slide member 98, through the slot 160 and aligned with the activating switch 156.
Having thus described the apparatus of the present invention in great detail, its operation will now be discussed. The solvent reservoir 26 is filled with solvent. First ball valve 36 is rotated to the open position so that solvent may flow through the first hollow coupling member 28 to the second hollow coupling member 40. Three way ball valve member 50 is rotated to the open position to permit solvent to flow from the second hollow coupling member 40 to the hollow cylinder 56. At the start of the cycle, the cap screw 115 is loosened to permit the T-Shaped nut 108 to move independently of the angle bracket 100. The nut 108 is screwed downwardly on the threaded rod 116 until it is adjacent base plate 14. The angle bracket 100 is then manually moved downwardly and slide member 98 is forced downwardly as well. In addition, since the horizontal portion 104 of angle bracket 100 is coupled to the rod end coupling member 78 as previously described, the rod end coupling member 78 and attached piston rod 76 are also forced to move downwardly. This in turn causes piston 66 to move downwardly inside chamber 57 of hollow cylinder 56. The dimensions of the apparatus are such that when the angle bracket 100 has been moved all the way down to where the lower horizontal surface of its horizontal portion 104 comes in contact with the horizontal portion 112 of T-shaped lead nut 108, the piston 66 is at the bottom of the cylinder. The movement of the piston 66 downwardly inside the chamber 57 creates a suction effect and solvent fills the chamber 57. With the chamber thus filled, first ball valve 36 is moved to the closed position to prevent further solvent from entering through the solvent reservoir 26 and three-way ball valve 50 is rotated to the opposite position so that solvent will go from the cylinder 57 to the solvent application nozzle.The cap screw 115 is also tightened.
The electrical start means 148 is activated and this causes air to enter the air cylinder 142 through first tubing 150 on the intake stroke and air to exit the air cylinder 142 through second tubing 152 on the exhaust stroke. When air enters the air cylinder 142, movable tip 144 moves forward and hits the arm portion 128 of movable lever arm assembly 124. As the arm 128 is thereby caused to move away from the air cylinder 142, it imparts a rotational motion to second one way clutch 122. This in turn cauess the threaded shaft 100 to rotate by a given amount which in turn causes the T-shaped nut 108 to rotate upwardly on said threaded rod by the same amount. As the T-shaped nut 108 moves up the threaded shaft 110, it causes the angle bracket 100 to move upwardly with it. This in turn causes the rod end coupling member 78 to move upwardly which in turn causes piston 76 to move upwardly. As the piston 76 moves upwardly, a selected amount of solvent is caused to exit the chamber 57 of hollow cylinder 56 and exit the nozzle where it is applied to the parts which are to be bonded together. The amount of rotation of the threaded rod 116 and corresponding vertical distance moved by the T-shaped nut 108, angle bracket 100 and piston 66 is determined by the stroke length of arm 128. This can be adjusted to any desired amount of setting first adjustable arm stopping means 138 and second adjustable arm stopping means 140 at the desired distance from the stop block 136 on arm 128.
On the exhaust cycle, the movable tip 144 returns to its at rest position as air is exhausted from the directional air valve 146. The return spring 132 causes the arm 128 to rotate back to its original position but first one-way clutch 122 prevents the threaded rod 116 from rotating with the moveable lever arm assembly 124. Therefore, the angle bracket 100 and its attachments and the piston 66 remain stationary during this cycle. The intake cycle on the air cylinder begins again and the process is repeated.
As the solvent is caused to exit the chamber 57 of hollow cylinder 56 through repeated cycles, the piston 66 moves upwardly and the angle bracket 100 and its attachments also move upwardly. This in turn causes the attached switch button activator member 158 to move upwardly. The parts are adjusted such that as the cylinder is nearing being empty, the top of the switch button activator member 158 comes in contact with the switch button 156 and activates the signalling means 154 to warn the operator that the cylinder 56 is nearly out of solvent. The operator can then stop the air cylinder electrical start means 148 and refill the cylinder through the process previously described.
Through use of the present invention, any type of solvent can use dispensed from the solvent pump 10. This includes conventional entirely fluid solvents such as cyclohexanone and also includes fluid solvents which contain solid particulates therein such as polyvinyl chloride mixed with cyclohexanone. This is due to that fact that the entire cylinder portion 56 and all other components which are directly in contact with the solvent while it is retained in the cylinder or dispensed therefrom to the parts to be bonded do not have any valves which may become occluded or otherwise impaired as previously described.
The embodiment described herein has been described in great detaili with specific parts. It will be appreciated that the present invention can be embodied in several alternative or comparable mechanical arrangements without departing from the spirit and scope of the present invention. For example, the solvent reservoir can be described generally as being supported by a mainframe member. The various detailed coupling members and the associated valves can be more generally described as connecting means interconnecting the solvent reservoir to the internal chamber of the hollow solvent cylinder. The valves which permit the solvent to flow from the reservoir to the interconnecting means and from the interconnecting means to either the solvent cylinder or alternatively from the solvent cylinder to the solvent ejection nozzle can be described as adjsutable valve means. The specific pair of one-way clutches can be more generally described as one-way clutch means. The entire structure of the movable slide member, the angle bracket member and the Tshaped lead nut can be more generally described as piston rod moving means. The movable lever arm assembly can be more generally described as rod rotating means. The embodiment of the stop block and the adjustable pair of arm stopping means can be more generally described as adjustable stopping means.
Defined even more broadly, the entire hollow solvent cylinder can be defined as solvent holding means while the internal piston and its associated components can be defined as solvent ejection means. The entire slide member, angle bracket, T-shaped lead nut and its interconnection with the generally H-shaped member can be more broadly defined as longituidnal movement means. The entire lever arm assembly and its associated components and the pair of one-way clutches can be more broadly defined as rotation means causing the longitudinal movement means to rotate in one direction only and simultaneously move in a longitudinal direction by a predetermined amount.
It is clear that the broad concept of the present invention is to provide a series of interconnected mechanical components which permit the solvent to be ejected from the solvent cylinder in precise predetermined amounts through the longitudinal movement of solvent ejection means such as the piston inside the cylinder and to eliminate any valves which may become occluded with particulate matter from being involved in the repetative solvent ejection process. The series of precise mechanical components can be varied without departing from the spirit and scope of the present invention.
Of course the present invention is not intended to be restricted to any particular form or arrangement, or any specific embodiment disclosed herein, or any specific use, since the same may be modified in various particulars or relations without departing from the spirit or scope of the claimed invention hereinabove shown and described of which the apparatus shown is intended only for illustration and for disclosure of an operative embodiment and not to show all of the various forms or modification in which the invention might be embodied or operated.
The invention has been described in considerable detail in order to comply with the patent laws by providing a full public disclosure of at least one of its forms, However, such detailed description is not intended in any way to limit the broad features or principles of the invention, or the scope of patent monopoly to be granted. | A pump for delivering precisely metered discrete quantities of solvent containing suspended solids in rapid cycles. The pump ejects the solvent from a cylinder in amounts proportional to discrete longitudinal movement of a piston inside the cylinder and eliminates internal valves that may become clogged. | 5 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a liquid jet recording head for use in a liquid jet recording apparatus of an ink jet system for discharging the recording liquid (ink) as liquid droplets from the discharge ports (orifices), and a manufacturing method thereof, as well as a liquid jet recording apparatus with said liquid jet recording head mounted thereon.
2. Related Background Art
The liquid jet recording apparatuses of ink jet systems are very sensitive to disturbance, while features such as sufficiently high frequencies of producing droplets, ease of achieving the higher speed, higher precision, and multi-color printing are greatly expected in the future.
A liquid jet recording head of such a liquid jet recording apparatus comprises a substrate having discharge energy generating elements, and a nozzle layer (liquid flow passage forming layer) for forming liquid flow passages or a liquid chamber in communication to discharge ports (orifices) thereon, said substrate being typically subjected to thermal oxidation of the surface of a Si substrate of single crystal, and then formed with discharge energy generating elements such as electrothermal converting elements by well-known photolithography, its surface covered with an electrically insulating layer made of SiO 2 , SiC, or Si 3 N 4 , and a protective layer such as a Ta film for preventing damage (cavitation erosion) to discharge energy generating elements caused by mechanical impact in discharging the recording liquid, with a Ta 2 O 5 film provided to reinforce the intimate contact between the electrically insulating layer and the Ta film, if necessary. Also, a glass ceiling plate with an inlet opening for supplying the recording liquid such as ink to the nozzle layer is laid on the nozzle layer, said ceiling plate being bonded to the nozzle layer by adhesive.
The manufacturing methods for the liquid jet recording head with the above constitution can be classified into the four types as follows.
(1) Patterning a glass ceiling plate bonded with a dry film, and joining it to a substrate (see Japanese Laid-Open Patent Application No. 56-123869).
(2) Molding a nozzle layer made of resin by injection molding, and joint it to a substrate (see Japanese Laid-Open Patent Application No. 3-101954).
(3) Providing a resist pattern on a substrate, applying a resin film thereto, joining a ceiling plate thereto, curing the resin film, and then dissolving away the resist (see Japanese Laid-Open Patent Application No. 62-253457).
(4) Subjecting the surface of a second substrate which is comprised of a Si substrate of single crystal, as parent material, like a first substrate (heater board) having discharge energy generating elements, to anisotropic etching, to create V-character grooves, and bonding this substrate as a nozzle layer to the first substrate. Processing the surface of the second substrate constituting the nozzle layer to be a (100) plane, and forming the grooves of V-character in cross section by anisotropic etching at an etching rate for (111) plane of substantially zero (see Japanese Laid-Open Patent Application No. 54-150127).
In recent years, the liquid jet recording apparatus has advanced for the faster speed, greater precision, and higher image quality, and therefore, the development of liquid jet recording heads with ease of fabrication for the higher density of liquid flow passages, and the capability of higher discharge frequency, is desired. Also, one way of printing on plain paper is to use a strong base ink with the addition of urea. In this case, it is also necessary to improve the ink resistance property of structural members constituting the liquid flow passages in the liquid jet recording head, and the chamber.
However, according to the above-mentioned conventional arts, the liquid jet recording heads fabricated by the methods of (1) to (3), as previously described, all have the nozzle layer formed of resin, and are significantly limited in the materials from the viewpoint of the ink resistance property. Also, to promote the higher density of liquid flow passages, each liquid flow passage is required to have a high aspect ratio, i.e., a narrow width and greater height in cross section, but with the methods of (1) and (2), which use photosensitive resin, it is difficult to produce a high aspect ratio, and with the method of (3), which adopts the injection molding, it is also difficult to attain a sufficient shape precision if the liquid flow passages have a high aspect ratio.
To provide the liquid jet recording head operable at high frequencies for discharging, the cross-sectional dimensions of each liquid flow passage are required to be large, and to avoid the larger dimensions of the liquid jet recording head, the liquid flow passages are also required to have a high aspect ratio.
A method of (4) is superior in the ink resistance property, satisfactory in heat resistance, and simple in the manufacturing process, because the second substrate for the nozzle layer is the same Si material as the first substrate for the heater board, further with the advantages of having uniform ink wettability and stable discharge performance, owing to the orifice face to which discharge orifices are opened being constructed by the end faces of both Si substrates. However, since the grooves formed by anisotropic etching as above described do not allow the aspect ratio to be changed, and the second substrate has its bottom surface having the V-character shaped grooves facing down toward the heater board and joined thereto, the liquid flow passages with higher density will reduce the unetched width, resulting in unsolved problems of producing a lot of defectives.
SUMMARY OF THE INVENTION
The present invention has been achieved in the light of the aforementioned conventional problems, and its object is to provide a liquid jet recording head in which it is easy to fabricate liquid flow passages having a high aspect ratio and a high shape precision, and accordingly, can significantly promote the higher precision and faster speed of printing, having satisfactory ink resistant property and heat resistance, and stable discharge performance, and a manufacturing method thereof, as well as a liquid jet recording apparatus with said liquid jet recording head mounted thereon.
To accomplish the above object, a liquid jet recording head of the present invention comprises discharge energy generating means for generating discharge energy in the recording liquid, and a liquid flow passage forming substrate for forming liquid flow passages through which the recording liquid is flowed toward the discharge ports, characterized in that the surface of said liquid flow passage forming substrate and the lateral surfaces of said liquid flow passages are constituted of a (110) plane of single crystalline silicon and a pair of (111) planes perpendicular thereto, respectively.
A manufacturing method of a liquid jet recording head according to the present invention is characterized by including the steps of making a liquid flow passage forming substrate having the surface composed of a (110) plane of single crystalline silicon, and subjecting this substrate to anisotropic etching to form liquid flow passages having the lateral surfaces composed of a pair of (111) planes perpendicular to said (110) plane.
It is preferable to include a step of laminating the liquid flow passage forming substrate with liquid flow passages formed on a support substrate for supporting discharge energy generating means.
It is possible to include a step of laminating said liquid flow passage forming substrate on the support substrate before subjecting said liquid flow passage forming substrate to anisotropic etching.
Also, it is possible to include a step of laminating a ceiling plate on said liquid flow passage forming substrate before subjecting said liquid flow passage forming substrate made of single crystalline silicone to anisotropic etching.
This constitution is one of forming liquid flow passages by subjecting the liquid flow passage forming substrate made of single crystalline silicone to anisotropic etching. With the constitution of the present invention, the liquid flow passage forming substrate is fabricated with a (110) plane of single crystalline silicon as the surface, and liquid flow passages having a square cross section with a pair of (111) planes as the lateral faces can be formed by anisotropic etching with an etching rate for the (111) planes perpendicular to said (110) plane substantially equal to zero.
Also, since the liquid flow passages are square in cross section, it is possible to form liquid flow passages with high aspect ratio and high shape precision by increasing the thickness of the liquid flow passage forming substrate, or the etching depth.
If liquid flow passages extending through the liquid flow passage forming substrate are formed by anisotropic etching, by laminating the ceiling plate on the liquid flow passage forming substrate or the liquid flow passage forming substrate on the support substrate before subjecting said liquid flow passage forming substrate to anisotropic etching, it is unnecessary to control the etching depth because the depth of liquid flow passages can be determined only by the thickness of the liquid flow passage forming substrate.
Also, by making the liquid flow passage forming substrate and the support substrate of the same Si substrate, the ink resistant property or heat resistance of the liquid jet recording head can be improved, with the ink wettability around the discharge ports even, to stabilize the discharge performance.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1A and 1B show liquid jet recording heads in a first example, wherein FIG. 1A is a typical partial perspective view showing a part thereof, and FIG. 1B is a typical partial cross-sectional view showing a part of the cross section in a direction of thickness of a nozzle layer in FIG. 1A.
FIGS. 2A, 2B and 2C are explanatory views for showing the steps of manufacturing the liquid jet recording head of FIGS. 1A and 1B.
FIGS. 3A and 3B show liquid jet recording heads in a second example, wherein FIG. 3A is a typical partial cross-sectional view showing a part thereof, and FIG. 3B is a typical partial cross-sectional view showing another cross section.
FIGS. 4A and 4B show liquid jet recording heads in a third example, wherein FIG. 4A is a typical partial cross-sectional view showing a part thereof, and FIG. 4B is a typical partial cross-sectional view showing another cross section.
FIG. 5 is a view showing a liquid jet recording apparatus.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The embodiments of the present invention will be described below with reference to the drawings.
FIGS. 1A and 1B show liquid jet recording heads E1 in the first example, wherein FIG. 1A is a typical partial perspective view showing a part thereof, and FIG. 1B is a typical partial cross-sectional view showing a part of a nozzle layer in cross section in the thickness direction. The liquid jet recording head E1 comprises a substrate (heater board) 10 which is a support substrate having electrothermal converting elements (discharge energy generating elements) which are discharge energy generating means as hereinafter described, and the connecting wires, and the nozzle layer 20 which is a liquid flow passage forming substrate laminated on the substrate 10, the nozzle layer 20 having a plurality of liquid flow passages 21 formed by anisotropic etching as hereinafter described, and a common liquid chamber 22 in communication with them, with an orifice (discharge port) 23 formed at an open end of each liquid flow passage. Also, on the upper face of the nozzle layer 20 is provided an inlet opening 20a for supplying the ink which is the recording liquid to the common liquid chamber 22.
The substrate 10 comprises a Si substrate 11, a heat accumulating layer 12 formed as a film by thermal oxidation of SiO 2 on its surface, a heating resistive layer 13 made of HfB 2 formed as a film by sputtering on a predetermined portion of the heat accumulating layer 12, and a connecting wire 14 adhered thereon, the connecting wire 14 being made by forming an Al film on the surface of the heating resistive layer 13, and patterning it by well-known lithography, with a part of the heating resistive layer 13 exposed to an interrupted portion of the connecting wire 14 as a heating portion to constitute an electrothermal converting element 15.
The surface of the connecting wire 14 or the electrothermal converting element 15 is covered with an insulating layer 16 of Si 3 N 4 formed as a film by bias sputtering, and further the surface of the insulating layer 16 is covered with a protective layer 17 of Ni to prevent damage by cavitation of the ink.
The ink supplied via the inlet opening 20a into the common liquid chamber 22 is partly heated and vaporized by each electrothermal converting element 15 within each liquid flow passage 21, and is discharged through each orifice 23 as liquid droplets. At this time, the protective layer 17 protects the electrothermal converting elements 15 from cavitation of the ink.
A way of making the nozzle layer 20 is as follows. As shown in FIG. 2A, a second Si substrate 20b having a thickness of 1.1 mm with a (110) plane of silicon single crystal as the surface, and made of the same material as the Si substrate 11 in the substrate 10 which is heater board, is fabricated, a thermal oxidized film is formed on its surface, a resist pattern R1 having a shape of liquid flow passage having a width of 25 μm and a length of 150 μm is provided, and the thermal oxidized layer is etched with this resist pattern as the mask to remove a portion having a shape of the liquid flow passage and the common liquid chamber, as shown in FIG. 2B. For etching of the thermal oxidized film, a mixed liquid of hydrofluoric acid and ammonium fluoride is used. With the thermal oxidized film 20c patterned in this way as the mask, an exposed portion of the Si substrate 20b is subjected to anisotropic etching by KOH solution down to a depth of 50 μm, to form the liquid flow passages 21 and the common liquid chamber 22, as shown in FIG. 2C.
Since the anisotropic etching by KOH solution has a fast etching rate for a (110) plane of silicon single crystal, and on the other hand, has an extremely slow etching rate for a (111) plane which is perpendicular to the (110) plane, the liquid flow passage 21a becomes groove having a square cross section with its lateral face perpendicular to the surface of the Si substrate 20b. The Si substrate 20b formed with the liquid flow passages 21 and the common liquid chamber 22 in this way is bonded onto the substrate 10, with its surface facing down, as shown. The adhesives as used herein include an epoxy-type adhesive. An obtained laminate is cut along a predetermined section to open the end of liquid flow passages 21, thereby forming the orifices 23 (see FIGS. 1A and 1B). Note that the common liquid chamber 22 may be preformed on the Si substrate 20b by any well-known grooving technique.
Finally, an driving IC is bonded onto an electrode not shown conducting to the connecting wire 14 of the substrate 10 to connect an ink supply tube to the inlet opening 20a, thereby completing a liquid jet recording head E1.
As a result of making a print test using the completed liquid jet recording head, it has been found that the discharge performance is extremely excellent.
Since the liquid flow passages of the liquid jet recording head in this example are grooves of square cross section formed by subjecting the Si substrate with a (110) plane of single crystalline silicone as the surface to anisotropic etching along a (111) plane, the depth or width of grooves can be arbitrarily set by controlling the size of the masking opening or the etching time. That is, it is possible to freely make greater the aspect ratio of liquid flow passages, without fear that the unetched width becomes less sufficient in narrowing the interval between liquid flow passages, as will occur with the liquid flow passages comprised of the V-character grooves as seen in cross section, thereby restricting the higher density of liquid flow passages. Accordingly, the higher precision and higher speed for the printing can be greatly promoted.
In addition, since the substrate for the heater board and the nozzle layer are the same material, the ink wettability of the orifice face is uniform, and accordingly, the discharge performance is extremely stable, with the ink resistance property or heat resistance of the nozzle layer being sufficient, thereby resulting in enhanced durability of the liquid jet recording head, and greatly reduced limitations concerning the material of the recording sheet.
FIGS. 3A and 3B show liquid jet recording heads E2 in the second example, wherein a Si substrate like the Si substrate 20b in the first example is first adhered onto a substrate 10 which is a heater board by epoxy type adhesive, and the surface of the Si substrate is abraded to reduce its thickness to a required height, e.g., 50 μm, of liquid flow passages 31. Subsequently, in the same way as the first example, a thermal oxidized film is provided on the surface of the Si substrate, and patterned, to form the openings by anisotropic etching, which are then made into liquid flow passages 31.
Since the surface of the substrate 10 is covered with a protective layer 17 as previously described, the etching is ended if the protective layer 17 is exposed. Accordingly, the height of liquid flow passages 31 is equal to the thickness of the Si substrate. On the nozzle layer 30 formed in this way, a ceiling plate (lid plate ) 40 comprised of a Si substrate made of the same material as this nozzle layer is placed thereon and bonded together. Note that an inlet opening for supplying the ink into a common liquid chamber 32 of the nozzle layer 30 is provided on the ceiling plate 40 in this example.
The substrate 10 for the heater board is the same as in the first example, thus indicated by the same numeral, and no more described.
In this example, the height of liquid flow passages can be determined by the thickness of the Si substrate for the nozzle layer, without need of strictly managing the etching time for anisotropic etching as in the first example.
FIGS. 4A and 4B show liquid jet recording head E3 in the third example. This head is fabricated by first integrating a Si substrate for a nozzle layer 50 with a Si substrate for a ceiling plate (lid plate) 60, abrading the surface of the Si substrate for the nozzle layer down to a predetermined thickness in the same way as the second example, then forming liquid flow passages 51 by anisotropic etching, and bonding it together with a substrate 10 which is heater board.
The juncture between the Si substrate for the nozzle layer 50 and the ceiling plate (lid plate) 60 is accomplished by heating both substrates, which are integrated together, up to 800° C. in the nitrogen atmosphere for thermal fusion of the joining faces thereof. Since the nozzle layer 50 and the ceiling plate 60 can be strongly bonded by thermal fusion, the liquid jet recording head which is superior in ink resistance property and the mechanical strength can be obtained.
A liquid jet recording apparatus to which the liquid jet recording head of the present invention is applied, as shown in FIG. 5, will be described below.
In FIG. 5, 101a to 101d are liquid jet recording heads of line type (hereinafter referred to as "heads"), which are securely supported by a holder 102 which is a support in a direction of the arrow X with a predetermined spacing therebetween, parallel to one another. On the bottom face of each head 101a to 101d, discharge ports are provided, directed downwardly, at an interval of 16 openings/mm per column along a direction of the arrow Y, thereby enabling the recording in a width of 216 mm.
Each of these recording heads 101a to 101d is a system of discharging the recording liquid, using heat energy, under the control of discharging by a head driver 120.
Note that a head unit containing the heads 101a to 101d and the holder 102 is composed to be movable vertically by head moving means 124.
Note that the caps 103a to 103d disposed corresponding to the heads 101a to 101d and adjacent to the bottom portion thereof contain an ink absorbing member such as a sponge internally.
The caps 103a to 103d are securely supported by a holder, not shown, a cap unit containing the holder and the caps 103a to 103d are composed to be movable in a direction of the arrow X by cap moving means 125.
The heads 101a to 101d are supplied with color inks of cyan, magenta, yellow and black from the ink tanks 104a to 104d through the ink supply tubes 105a to 105d, respectively, thereby allowing the color recording.
Also, this ink supply makes use of the capillary phenomenon of discharge ports of the head, with the liquid level of each ink tank 104a to 104d being set a predefined distance below the location of discharge ports.
A belt 106 conveys the recording sheet 127 which a recording medium, and is comprised of an electrifiable seamless belt.
The belt 106 is stretched around a drive roller 107, idle rollers 109, 109a, and a tension roller 110 along a predetermined path to connect to the drive roller 107, and is run by a belt drive motor 108 which is driven by a motor driver 121.
Also, the belt 106 is run immediately below the discharge ports for the heads 101a to 101d in the direction of the arrow X, and is suppressed from vibrating downwards by a fixing support member 126.
Under the belt 106 as shown, a cleaning unit 117 is disposed for cleaning away the paper powder sticking to the surface of the belt 106.
An electrifier 112 for electrifying the belt 106 is turned on or off by an electrifier driver 122, so that the recording sheet 127 is adsorbed onto the belt 106 owing to an electrostatic adsorbing force of this electrification.
Disposed before and after the electrifier 112 are pinch rollers 111, 111a to press the recording sheet 127 to be conveyed onto the belt 106, in cooperation with the idle rollers 109, 109a.
The recording sheets 127 within a paper supply cassette 132 are fed one by one by rotation of a paper supply roller 116, conveyed by a conveying roller 114 which is driven by the motor driver 123 and a pinch roller 115 in the direction of the arrow X to an angled guide 113. The angled guide 113 has an angled space permitting the recording sheet 127 to be flexed.
The recording sheet 127 which has been recorded is exhausted into a paper exhaust tray 118.
The head driver 120, head moving means 124, cap moving means 125, the motor drivers 121, 123, and the electrifier driver 122 are all controlled by a control unit 119.
The present invention brings about excellent effects particularly in a recording head or recording apparatus of a so-called ink jet recording system for recording by forming flying liquid droplets using heat energy among various liquid jet recording systems.
As to its representative constitution and principle, for example, one practiced by use of the basic principle disclosed in, for example, U.S. Pat. Nos. 4,723,129 and 4,740,796 is preferred. This system is applicable to any of the so-called on-demand type and the continuous type.
Briefly describing this recording system, by supplying a discharge signal from a drive circuit to electrothermal converting elements which are discharge energy generating elements arranged corresponding to the sheets holding the recording liquid (ink) or liquid flow passages, namely, by applying at least one drive signal which gives rapid temperature elevation producing film boiling phenomenon, and exceeding nucleus boiling, to the recording liquid (ink), corresponding to recording information, heat energy is generated to effect film boiling at the heat acting surface of the recording head. In this way, the bubbles within the recording liquid (ink) can be formed corresponding one-to-one to the driving signals to the electrothermal converting elements, and therefore this system is particularly effective for the recording of on-demand type. By discharging the liquid (ink) through an opening for discharging by growth and shrinkage of this bubble, at least one droplet is formed. By making these driving signals into the pulse shapes, growth and shrinkage of the bubbles can be effected instantly and adequately to accomplish more preferably discharging of the liquid (ink) particularly excellent in response characteristic. As the driving signals of such pulse shape, those as disclosed in U.S. Pat. Nos. 4,463,359 and 4,345,262 are suitable. Further excellent recording can be performed by employment of the conditions described in U.S. Pat. No. 4,313,124 of the invention concerning the temperature elevation rate of the above-mentioned heat acting surface.
As the constitution of the recording head, in addition to the combination of the discharging orifice, liquid channels, and electrothermal converting element (linear liquid channel or right-angled liquid channel) as disclosed in the above-mentioned respective specifications, the constitution by use of U.S. Pat. Nos. 4,558,333 or 4,459,600 disclosing the constitution having the heat acting portion arranged in the flexed region is also included in the present invention.
In addition, the present invention can be also effectively made the constitution as disclosed in Japanese Laid-Open Patent Application No. 59-123670 which discloses the constitution using a slit common to a plurality of electrothermal converting elements as the discharging portion of the electrothermal converting element or Japanese Laid-Open Patent Application No. 59-138461 which discloses the constitution having an opening for absorbing a pressure wave of heat energy correspondent to the discharging portion.
Further, the present invention is effectively usable for a recording head of the full line type having a length corresponding to the maximum width of the recording medium which can be recorded by the recording device. This full-line head may take either a full-line constitution comprised of the combination of a plurality of recording heads or a constitution of one full-line recording head integrally formed.
In addition, the present invention is effective for the use of a recording head of the freely exchangeable chip type which enables electrical connection to the main device or supply of ink from the main device by being mounted on the main device, or a recording head of the cartridge type which is integrated on the recording head itself.
Also, addition of a restoration means or preliminary auxiliary means, etc. to the recording head is preferable, because the recording apparatus is further stabilized. Specific examples of these may include, for the recording head, capping means, cleaning means, pressure or suction means, electrothermal converting elements or another type of heating elements, or preliminary heating means according to a combination of these, and it is also effective for performing stable recording to add preliminary discharge mode means which performs discharging separate from recording.
As the recording mode of the recording device, the present invention is extremely effective for not only the recording mode only of a primary color such as black, etc., but also a device equipped with at least one of plural different colors or full color by color mixing, whether the recording head may be constituted integrally or by a combination of plural heads.
The most effective method for the ink as above described in the present invention is based on the film boiling.
Furthermore, the ink jet recording apparatus according to the present invention may be used as an image output terminal in an information processing equipment such as a computer, a copying machine in combination with a reader, or facsimile terminal equipment having a transmission and reception feature.
Though the ink is considered as the liquid in the examples of the invention as above described, another ink may be also usable which is solid below room temperature and will soften or liquefy at or above room temperature, or in a temperature range from 30° C. to 70° C. within which the temperature can be adjusted commonly with the ink jet device. That is, what is needed is that the ink can liquefy when a use recording signal is issued. In addition, in order to avoid the temperature elevation due to heat energy by positively utilizing it as the energy for the change of state from solid to liquid, or to prevent the evaporation of ink by using an ink which is solid when in the on-the-shelf state, the use of an ink having a property of liquefying only with the application of heat energy, such as liquefying with the application of heat energy in accordance with a recording signal so that liquid ink is discharged, or may already solidify upon reaching the recording medium, is also applicable in the present invention. In such a case, the ink may be held as liquid or solid in recesses or through holes of a porous sheet, which is placed opposed to electrothermal converting elements, as described in Japanese Laid-Open Patent Application No. 54-56847 or No. 60-71260. The present invention can be most effectively applied to the film boiling system for each ink as above mentioned. | A liquid jet recording head comprising discharge energy generating means for generating discharge energy in the recording liquid, and a liquid flow passage forming substrate for forming liquid flow passages through which the recording liquid is flowed toward the discharge ports, characterized in that the surface of said liquid flow passage forming substrate and the lateral faces of said liquid flow passages are constituted of a plane of single crystalline silicone and a pair of planes perpendicular thereto, respectively. | 1 |
BACKGROUND OF THE INVENTION
[0001] The present invention relates to a bible field enhancer. More particularly, the invention relates to a bible field enhancer that is effective in treating and controlling patient's pain.
[0002] The Dermatron is an analytical instrument (EAV: electroacupuncture According to Voll) developed in the 1950's by Dr. Voll in Germany to analyze the energy state of health of Chinese acupuncture meridians which reflect the energetic state of health of various body systems, i.e., heart, small intestines, endocrine, lung etc. A skin probe is used to measure the electrical skin resistances on a meter. This meter is scaled from zero to 100, where 50 represents a normal healthy state. 51-100 represents, progressive inflammatory disease states, and 0-49 represents progressive degeneration states. Plain and infection manifestations are in the inflammatory zone and cancer in the degenerative zone (Refer to FIG. 7 ).
[0003] The Dermatron also has the capability to determine the therapeutic of harmful effects of medicine, vitamins, herbs, food, etc. on any meridian when it is placed in the electrical probe circuitry. Even the benefits of prayer can be determined. It has often been found for the average devout Christian that their prayers for mild illness help for about one minute when measured on the Dermatron. True healing will show persistent reading of 50 indefinitely.
[0004] About five years ago, the inventor found that reading a popular verse (John 3:16) transiently improved the meter reading for about 30 seconds. Testing several conditions such as reading a Xerox copy, reading with eyes closed, reading in silence, reading at a distance away from the Bible had no benefits. Maps, pictures, commentaries weaken the benefit. It was concluded that the Bible has a field phenomenon or characteristic. Because the body meridians represent bio-field characteristics on the skin, the bible field also has a therapeutic bio-field body. This human property could be reflective of an undiscovered spiritual presence of God in the Bible text. The problem is that this Bible field created by the word text of the Bible is so weak that it has remained undetectable, elusive and of no practical value. But if it could be amplified thousands of time, it could be a constant, predictable, easily administrable, free and inexhaustible source of healing power to help impact the crushing cost of chronic care throughout the world. The divine presence of God is not just limited only to pain but potentially to all diseases.
[0005] The Bible Field Enhancer was invented through extensive research and development. It amplified the bible field to a level where you do not have to read any passages in the Bible, just stand in front of it for about 30 minutes. Nearly all patients have felt relief immediately and have been nearly pain free for 1-2 weeks at least with one treatment. The Dermatron also reflects these improvements.
SUMMARY OF THE INVENTION
[0006] The present invention contrives to solve a problem that has not been addressed by the prior art.
[0007] An object of the invention is to provide a bible field enhancer that enhances a bible field.
[0008] Another object of the invention is to provide a bible field enhancer that is effective in treating patient's pain.
[0009] To achieve the above objects, the present invention provides a bible field enhancer that enhances a bible field of a bible. The bible field enhancer operates a receiver that is adapted to receive the bible field. The receiver includes a first hollow cone and the cone has an outer surface, an inner surface, an apex closed end and a base open end. The apex open end of the cone is adapted to be located close to the bible.
[0010] The cone is made of titanium and has a bible jacket holder attached to the outer surface. The bible jacket holder holds bibles incased with a gold leaf lined copper foil sheet.
[0011] The cone consist of an apex cone segment closed at the tip on one end and open at the base measuring 5¾ inches in diameter at the other end. This apex segment measures 41 inches in length.
[0012] The receiver may have a second hollow middle cone with an outer surface, an inner surface, a smaller open end and a larger base open end, and the smaller open end of the second cone surrounds the base open end of the first cone. The second measures 28 inches in length and measures from about 6 inches to 10 inches in diameter at the smaller open end and the base open end respectively. The receiver may have a third hollow or distal cone segment with an outer surface and an inner surface, a smaller open end, and a larger base open end. The smaller open end of the third cone surrounds the base open end of the second cone segment. The third cone segment measures 48 inches in length and measures from about 10¾ inches to 14½ inches in diameter at the smaller open end and base open end, respectively.
[0013] The bible field enhancer further includes a bible pedestal that supports the bible in unfolded state and the apex closed end of the cone is close to the bible pedestal.
[0014] Plain bible for the bible field enhancer has the best result, and bible with commentation has interference. Judeo-Christian bible is the best in the original text. Hebrew old testament and new testament version are the best, or alternatively, the old and new testaments written completely in those of the King James Version, in original text, or any accurate translation into any language.
[0015] Although the present invention is briefly summarized, the fuller understanding of the invention can be obtained by the following drawings, detailed description, and appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] These and other features, aspects and advantages of the present invention will become better understood with reference to the accompanying drawings, wherein:
[0017] FIG. 1 is a perspective view showing a bible field enhancer according to the present invention;
[0018] FIG. 2 is a top view of the bible field enhancer;
[0019] FIG. 3 is a rear elevation view of a receiver cone;
[0020] FIG. 4 is a front elevation view of the receiver cone;
[0021] FIG. 5 is an elevation view of a bible jacket holder;
[0022] FIG. 6 is a perspective view showing the bible field enhancer with the apex of the receiver cone is covered with sheets of a bible; and
[0023] FIG. 7 is a perspective view of a meter that shows electrical skin resistance.
DETAILED DESCRIPTION OF THE INVENTION
[0024] FIG. 1 shows a bible field enhancer 10 according to the present invention. The bible field enhancer 10 includes a hollow receiver cone 9 and a bible jacket holder 11 that is attached along the receiver cone 9 . The bible field enhancer 10 enhances the bible field of a bible 12 a that is placed on a bible pedestal 50 , and a plurality of bibles 12 b that are enclosed in the bible jacket holder 11 . The receiver cone 9 is supported by pedestals 8 a and 8 b . While there is no ideal size or minimum size required for the receiver cone 9 , preferably the height to base diameter ratio is 7 to 1 or more. The larger the receiver cone, the stronger the bible field by allowing more bibles attached to it.
[0025] FIG. 2 shows that the receiver cone 9 are provided as an assembly of three cone segments 9 a , 9 b , and 9 c , and the bible jacket holder 11 are provided as three separate jacket holders 11 a , 11 b , and 11 c that are attached to the cone segments 9 a , 9 b and 9 c , respectively. The cone segments 9 a , 9 b and 9 c are made of commercial grade 2-quality titanium, and have 0.02 inch thickness. Black duct tapes and Velcro patches are used to stabilize the cone segments. Tight tolerances between the dimensions of the cone segments are not critical.
[0026] Referring to FIGS. 3 and 4 , the cone segment has an apex 52 that is a closed and sharp point. The cone segments 9 a , 9 b , 9 c includes outer surfaces 18 a , 18 b , 18 c , and inner surfaces 20 a , 20 b , 20 c , respectively. The cone segment 9 a has 41″ length, and diameter from 0 to 5¾ inches. The cone segment 9 b has 28″ length, and diameter from 6 to 10 inches. The cone segment 9 c has 48″ length and diameter from 10¾-14¼ inches. The middle cone segment 9 b overlaps with the apex cone segment 9 a and the distal cone segment 9 c , and the overall assembled length is about 115 inches. Distilled water may be filled inside the receiver cone 9 . The effect with distilled water in the cone chamber is superior to ambient air.
[0027] Referring to FIG. 5 , the bible 12 b includes a Gideon bible with covers removed. Each of the jacket holders 11 a , 11 b and 11 c includes a copper foil panel 54 , and a plurality of gold leaves 56 that are lined up and layered over the copper foil panel 54 . The gold leaf 56 , or gold leaf paper is rectangular has a size of 3½ by 3½ inches. The copper foil panel 54 is precut to match the length of each of the cone segments and is wide enough to fold over the back, binding and front of the bible 12 b . The copper foil panel has 0.20 inch thickness.
[0028] The bible 12 b is closed about 75%-80% with approximately 20%-25% open at the middle, page 647 of Gideon bible. The exposed portion is open at about 60-90 degrees angle to lay over the outer surface of the cone segment. The bibles 12 b directly contact the outer surface 18 a , 18 b , 18 c of the cone segments 9 a , 9 b , 9 c . Black duct tape and Velcro patches are used to hold the bible 12 b in this shape win the jacket holder 11 a , 11 b , 11 c . The bibles 12 b in the jacket holders are aligned so that they have the same orientation. The open ends of the bible jacket holders are aligned over the surface of the cone segments 9 a , 9 b , 9 c evenly. The jacket holders 11 a , 11 b , 11 c can be in any rotated position with respect to the cone segments 9 a , 9 b , 9 c . In FIGS. 2 and 6 , they are pointed upward. The jacket holders may lay sideways on a table for stability.
[0029] FIG. 6 shows that the detached open bible 12 a is sits on the bible pedestal 50 and is open in the middle. The apex 52 of the cone segment 9 a is projected about ⅔ way in the middle of the bible 12 a . The bible 12 a is closed over the top.
[0030] In use of the bible field enhancer 10 , people expose the part of their body in pain directly in front of the largest cone segment 9 c . The Judeo-Christian bible with the old and new testaments texts written completely in Hebrew is the best. However, most English versions though not as potent are still quite effective. Maps, red print and other commendations cause interference with the Bible field.
[0031] The following are a few case histories of patients that have benefited from exposure to the bible field enhancer after it was completed. Patients would expose the area of pain at a distance of 1-2 feet in front of the base open end of the cone for 20-30 minutes. They were not encouraged to pray or read the Bible.
EXAMPLE 1
[0032] A 65 years old female with rheumatism and early arthritis of both hands for 2 years complain of pain especially when she flexed her hands and finger. Even before finishing exposure to the Bible field she noticed improvement in the pain. After the treatment the pain continued to improve and was nearly gone. Checking with her in a few days the improvement was still significant and after 3 weeks, there still was come benefit.
EXAMPLE 2
[0033] A 60 years old male with borderline hypertension for 2 years has persistent readings of 140/90. He was not taking any hypertensive medication. After exposure to the bible field, his blood pressure a few hours later read 130/80. Checking the pressure the next day also remained the same, 130/80. One month later his blood pressure read 130/88.
EXAMPLE 3
[0034] A 42 years old female had a problem of amenorrhea for a few years. Missing her period made her feel swollen, bloated, sluggish and uncomfortable. Only by taking birth control pills or female period inducing hormone could she have normal periods. At the time of her next period, she was able to have a two-day flow with relief.
EXAMPLE 4
[0035] A 50 years old female had low chronic back pain for years. After exposure to the bible field, her low back soon felt significant relief. Checking with her a few days later, she was grateful that the relief was still present.
EXAMPLE 5
[0036] A 75 year old Chinese male that is not a Christian, had injured his low back as a youth and was forced since to lean his upper torso slight forward since. Trying to straighten up erect quickly would tighten up his low back and eventually cause pain. After exposure to the cone for 30 minutes he immediately was able to easily straighten up and maintain an erect posture for hours. The next day he still could stand erect easily. I took this opportunity to get him to accept the Lord which he was very receptive.
[0037] While the invention has been shown and described with reference to different embodiments thereof, it will be appreciated by those skilled in the art that variations in form, detail, compositions and operation may be made without departing from the spirit and scope of the invention as defined by the accompanying claims. | A bible field enhancer includes a receiver cone that is hollow, and the apex of which is positioned near a bible. The bible is open in the middle and closed over the top, wherein the apex of the receiver cone is projected about ⅔ way in the middle of the bible. The enhancer also includes a bible jacket holder that holds a partially opened bible, and is attached along the receiver cone. The receiver cone and the bible jacket holder may be provided as small units that are assembled to make a large cone. | 6 |
FIELD OF THE INVENTION
This invention relates to improvements in air-cooled, belt-fed, gas-operated machine guns. More particularly, it relates to improvements in the M60 7.62-mm machine gun described in detail in the Department of the Army Field Manual FM 23-67, dated October 1964.
BACKGROUND OF THE INVENTION
The M60 machine gun is an excellent weapon but improvements are possible and desirable. In particular, there are certain areas where improvements are especially desirable.
The M60 machine gun has its feeding mechanism arranged in a pivoted cover which is raised to load a belt of cartridges into the gun and then closed to render the feeding mechanism operative. The feeding mechanism includes cam means operated by the reciprocating bolt assembly which must be in its rearward position for proper engagement of the cam follower carried by the assembly with the cam means of the feeding mechanism when the cover is moved to closed position. Thus, when the bolt assembly is in its forward position with the cover open, if the latter is closed the bolt assembly cannot be moved rearwardly to cock the gun and if it is forced rearwardly there is a possibility of the cam follower thereon actually damaging the feeding mechanism. Thus, the present construction presents a possibility not only of damage to the feeding mechanism but also of a dangerous battle situation because of undue delay in cocking the weapon because the gunner must open the cover before he can retract the bolt assembly to cock the gun and then must reclose the cover before he can fire.
As mentioned above, the M60 machine gun is gas-operated. On occasion, for various reasons, gas pressure is insufficient to move the bolt assembly to its full rearward position for cocking engagement with the sear of the trigger mechanism. Even though the bolt assembly is not moved to its full rearward position, however, gas pressure may be sufficient to move the assembly rearwardly a distance sufficient to cause the feeding mechanism to feed another cartridge into position to be transferred by the bolt assembly into the barrel chamber and subsequently fired. The foregoing situation results in a runaway gun, i.e., it will continue to fire even though the trigger is released; manifestly a dangerous situation.
On prolonged firing, the barrel of the M60 machine gun becomes quite hot and for continued use must be replaced by the usual spare. To enable rapid replacement without delay, heat-insulating protective hand coverings, such as asbestos mittens, now are employed for removal of a hot barrel. The use of such mittens not only is an expensive nuisance but also contributes to delay in barrel replacement.
The M60 machine gun also is provided with a bipod support assembly secured to the barrel. The assembly is not readily detachable and removable from the barrel. Consequently barrel spares normally are provided with such bipod support assemblies, thus necessitating the provision of more than one bipod support assembly for each gun.
The gas-operated piston and cylinder of the M60 machine gun also is somewhat bulky and inaccessible for cleaning. The cylinder is provided with a cleaning port aligned with the barrel gas port, with the cleaning port being closed by a threaded plug. The forward end of the cylinder is closed by an extension held in place by a clamp nut with a lock washer. Both the plug and the extension of the cylinder are retained against loss by lock wires because the usual threads and lock nuts fail under extreme heat conditions. Since lock wires cannot be replaced readily in the field, the gas system is cleaned only infrequently with resulting possible sluggish operation of the gun. Furthermore, the cleaning port plug sometimes is lost and the gun thereby rendered inoperative because of loss of adequate gas pressure.
The rearward end of the gas cylinder is provided with interior threads engaged by exterior threads on a nut to provide a forwardly facing shoulder engageable by the piston on its rearward travel. Both this nut and the cylinder extension unnecessarily complicate the construction of the cylinder and piston arrangement and add unnecessary weight to the weapon.
It also has been found that control of the gun is difficult when firing from a standing position.
SUMMARY OF THE INVENTION
It is therefore an object of this invention to provide an improved feeding mechanism for the M60 machine gun which will enable the cover to be moved from open to closed positions while the bolt assembly is in its forward position and the bolt assembly subsequently to be moved to its rearward position to cock the gun with operative engagement of the cam follower thereon with the feeding cam means on the cover without opening the cover. Such improvement not only avoids the possibility of damage, as described above, but also avoids delay in cocking the gun in an emergency.
It is another object of this invention to provide an improved sear and notch means for the M60 machine gun which will reduce and minimize the possibility of a runaway gun.
It is another object of this invention to provide a carrying handle for the M60 machine gun that is secured to the barrel and which can be used for handling a hot barrel without the necessity for heat-insulating protective hand coverings, thus avoiding the expensive nuisance and delay attendant the use of such coverings.
It is another object of this invention to provide an M60 machine gun with a bipod support assembly that is secured to a fixed portion of the gun other than the barrel, so that the provision of a bipod support assembly for each barrel is unnecessary and only one such assembly need be provided for each gun.
It is another object of this invention to provide the M60 machine gun with an improved lightweight pistol grip detachably secured to the bipod support assembly in order to give improved control when firing, especially when firing from the hip or shoulder when standing or walking.
It is a further object of this invention to provide an improved and simplified gas-operated cylinder and piston construction which eliminates the necessity for lock wires and facilitates cleaning in the field while reducing the possibility of loss of parts required for operation of the gun and simplifying the entire construction and making it lighter in weight.
Other objects and advantages of the invention will become evident from the following detailed description and accompanying drawings in which:
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1A and 1B constitute related generally longitudinal vertical sectional views through adjacent portions of a machine gun embodying this invention;
FIG. 1C is a fragmentary view of the forward end of the gas cylinder shown in FIG. 1B;
FIG. 2 is a side view, partly in vertical section, of the cover mechanism shown in FIG. 1A;
FIG. 3 is a view of the underside of the cover mechanism shown in FIG. 2;
FIG. 4 is an enlarged fragmentary top view, partly broken away, taken on line 5--5 of FIG. 3;
FIG. 5 is an end view taken from the right hand end of FIG. 4; and
FIG. 6 is a side view of the part shown in FIG. 4.
DETAILED DESCRIPTION OF THE INVENTION
Referring now to FIGS. 1A and 1B of the drawings, there is shown a machine gun having a barrel 10 with its breech end detachably locked within a receiver assembly 12 by a rotatable lock pin 14. Mounted for repetitive cycles of reciprocating movement in the receiver assembly 12 is a bolt assembly 16 having a firing pin 18 coaxially mounted therewithin, the bolt assembly 16 is connected to a lower parallel hollow operating rod 20 by a yoke 22. The operating rod 20 is constantly urged forwardly, to move the bolt assembly forwardly by a coil compression drive spring 24 disposed within the rod and engaged between a solid extension 26 closing the forward end of the rod and the piston rod 28 of a buffer assembly 30 disposed within the gun stock 32. Carried on the receiver assembly 12 to the rear of the barrel 10, is a feed tray 34 for receiving and guiding a belt of linked cartridges (not shown) into position wherein the leading cartridge may be engaged by the bolt assembly 16, on its forward movement, fed into the chamber 36 of the barrel 10, and then fired by the firing pin 18.
The bolt assembly 16 is moved rearwardly, for another feeding and firing movement and to extract a spent cartridge after firing, by the operating rod 20 which is moved rearwardly by the development of gas pressure in the barrel 10, on the firing of a cartridge, which is communicated through a gas port 38 therein into a cylinder 40 secured to, beneath and parallel with, the barrel. A piston 42 is reciprocable in the cylinder 40 and is moved rearwardly by the gas pressure to engage the solid extension 26 of the operating rod 20 and forcibly move the rod rearwardly. When the rod 20 reaches its rearmost position, a notch 44 in the underside thereof is engaged by a sear 46 of the trigger mechanism 48, which is releasable by a trigger 50, to cock the gun. A cocking handle (not shown) is secured to the operating rod 20 and projects outwardly through a slot in the right hand side of the receiver assembly 12 to enable the gun to be cocked manually.
Pivotally mounted to the receiver assembly 12, for upward swinging movement from a closed firing position (shown in FIG. 1A) to an open loading position (not shown) about a pivot pin 52 secured to the receiver assembly adjacent the rear end of the barrel 10, is a cover assembly 54 which contains mechanism for feeding a belt of cartridges (not shown) step-by-step over the feed tray 34 to present the leading cartridge in a position to be engaged and fed into the barrel chamber 36 as aforesaid. The feeding mechanism includes feed cam means 56 in the form of an inverted trough extending generally longitudinally of the gun and pivotally secured at its rearward end, by a stud 58 depending from the top 60 of the cover assembly 54, for lateral oscillating movement. The feed cam means 56 has engaged in the trough thereof a cam roller or follower 62 secured to and projecting upright from the bolt assembly 16 so that reciprocating movements of the latter oscillate the feed cam means. Also secured to the cover assembly 54 for oscillating movement about a stud 64 depending from the top 60 thereof is a feed cam lever 66 having the rear end thereof provided with a slot engaged with an upright stud 68 on the feed cam means 56. Consequently, the feed cam lever 66 is oscillated by oscillation of the feed cam means 56. The forward end of the feed cam lever 66 has slotted engagement with a stud 70 on a reciprocating belt feed pawl 72. Thus, oscillation of the feed cam lever 56 feeds a belt of cartridges forwardly step-by-step to bring the leading cartridge into position to be engaged and fed into the barrel chamber 36 by the bolt assembly 16. The aforedescribed mechanism is known and described in the aforementioned Army Field Manual, so no further detailed description thereof is necessary here.
As mentioned before, the M60 machine gun, when the bolt assembly 16 is moved forward with the cover assembly 54 open and the latter then closed, cannot thereafter be cocked manually without first opening the cover assembly because with the latter closed the forward end of the feed cam means 56 is not in a position to be operatively engaged by the cam roller or follower 62 on the bolt assembly. Thus, in order to cock the weapon, the cover assembly 54 has to be opened, the bolt assembly 16 pulled to the rear manually and cocked, and the cover assembly then closed to render the weapon operative for firing. Under these circumstances, a gunner sometimes attempts to cock the weapon without opening the cover assembly 54 and applies considerable force in such an effort. The result is possible damage to the weapon, which will render it inoperative.
The aforementioned disadvantages are overcome by the present improvement wherein the forward end of the feed cam means 56 is contoured to be engaged by the cam roller or follower 62 when the cover assembly is closed with the bolt assembly 16 in its forward position so that rearward movement of the bolt assembly pivots the feed cam means into position to be operatively engaged by the cam roller or follower. Thus, the forward end of the feed cam means 56 has extending laterally from one side thereof, flush with the lower edge of one side wall 74 of the trough, a flange 76 having depending therefrom at the rearward edge thereof, a forwardly inclined cam rib 78. As later explained, the feed cam means 56 is arranged so that its forward end, in advance of the rear pivot stud 58, can yield somewhat upwardly relative to the top 60 of the cover assembly 54. Thus, when the bolt assembly 16 is in its forward position, and the cover assembly 54 moved from open to closed position, the laterally extending flange 76 on the feed cam means 56 engages with the top of the upstanding cam roller or follower 62 on the bolt assembly, and the forward end of the feed cam means yields upwardly to accommodate such engagement and enable the cover assembly to be closed completely. When the bolt assembly 16 is then moved manually rearwardly by the cocking handle, the top of the cam follower 62 rides along beneath the flange 76 until it engages the depending forwardly inclined cam rib 78 which pivots the feed cam means 56 laterally until the cam follower engages within the trough of the feed cam means. Spring means is then employed to urge the forward end of the feed cam means 56 downwardly so that the trough will snap over and operatively engage with the cam follower 62. The spring means includes a coil compression spring 80 surrounding the stud 68 and engaged between the base of the latter and a washer 82 engaged beneath the feed lever 66. The top 60 of the cover assembly 54 is provided with a recess 84 in its undersurface to accommodate upward movement of the stud 68 against the downward urging of the spring 80, when the lateral flange 76 on the feed cam means 56 engages the top of the cam follower 62.
It thus will be seen that when the bolt assembly 16 is in its forward position, it can always be moved rearwardly to cock the weapon irrespective of whether the cover assembly 54 is open or closed, and further irrespective of whether the bolt assembly has been moved to its forward assembly with the cover assembly open.
Referring now to the FIG. 1B of the drawings, it will be seen that the weapon is provided with a carrying handle 86 having a grip 88 of heat-insulating material, e.g., plastic, secured to one leg of a generally U-shaped rod 90, the other leg of which is secured for pivotal movement about a longitudinal axis in a bracket 92 secured to the rear end of the barrel 10 just in advance of the receiver assembly 12. The grip 88, when the handle 86 is in carrying position, preferably is adjacent the center of gravity of the gun to facilitate carrying the latter with one hand. The handle 86 can be pivotally moved to one side or the other for unobstructed vision through the rear sight 94 when the gun is in use. It also will be seen, however, that when the pivot lock pin 14 is disengaged, the handle 86, because of its heat-insulating grip 88, can be used to remove a hot barrel from the gun without the use of heat-insulating hand coverings. Spare barrels will be supplied with such a carrying handle, but the necessity and expense of providing each barrel with such a handle outweighs the expense, nuisance and delay attendant the use of protective hand coverings for replacing a hot barrel with a cool spare.
Referring again to FIG. 1B of the drawings, there is shown a bipod supporting assembly 96 that is disclosed in somewhat greater detail in my copending application, Ser. No. 137,780, filed Apr. 7, 1980, the disclosure of which is incorporated by reference herein. As described therein, the bipod assembly 96 has a mounting structure which includes a ring member 98 secured to the forward end of a tube 100 on the receiver assembly 12 which encloses the operating rod 20. The ring member 98 is secured in place by a set screw 102 threaded through the member and engaged with the tube 100. The tip of the screw 102 is reduced for engagement within a pilot aperture 104 in the tube 100 for proper alignment of the bipod assembly 96 on the tube. Also secured to the ring member 98 is a depending pistol grip of lightweight material, e.g., plastic, having a socket 108 engaged with a depending complementary portion 110 on the ring member and held in place by the head of the screw 102.
By means of the foregoing construction, it will be seen that each gun need be provided with only one bipod supporting assembly 96, thus avoiding the necessity of providing such an assembly for each spare barrel. At the same time, there is provided a simple pistol grip 106 depending between the rearwardly foldable legs 112 of the bipod assembly 96 which increases the gunner's control of the weapon when firing in a standing position, either from the hip or from the shoulder.
Referring again to FIG. 1B of the drawings, the gas cylinder 40, which is of simple smooth bore construction, is secured beneath and to the barrel 10 by two integral ring members 114 which surround the barrel. Extending through the forward ring member 114 in alignment with the lower radial gas port 38 in the barrel 10 is a passageway 116 which communicates the port with the interior of the cylinder 40. The rear end of the cylinder 40 is reduced to fit snugly within and provide support for the forward end of the tube 100 which encloses the operating rod 20, and also provide a forwardly facing interior shoulder 118 engageable by the piston 42 which reciprocates in the cylinder. The forward end of the cylinder 40 is closed by a plug 120 which has a skirt 122 threadedly engaged within the cylinder and extending past the radial passageway 116 to form a stop for forward movement of the piston 42 effected by the operating rod 20. The inner end of the skirt 122 is notched, as at 124, in alignment with the passageway 116 to permit gas to flow from the passageway into the cylinder 40. Correct alignment of the notch 124 with the passageway 116 is assured by a notch 126 in the outer end of the plug 120 in longitudinal alignment with the notch 124. The plug 120 is held in place by a clamp nut 128 threaded onto the forward end of the cylinder 40. The plug 120 is installed by threading it into the cylinder 40 until the flange on the plug abuts the forward end of the cylinder. The plug is then unthreaded until the notch 126 is in vertical alignment with the barrel 10. The clamp nut 128 is then installed. The pitch of the threads on the plug 120 is greater than those in the nut 128 to eliminate the need for a locking wire or other securing means to hold the plug and nut in place. Opposite the inner end of the gas passageway 116, the cylinder is provided with a cleaning port 130 normally closed by the skirt 122 on the plug 120. When the latter is removed, however, a cleaning tool (not shown) can readily be inserted through the cleaning port 130 and through the gas passageway 116 to clean the gas port 38 in the barrel 10.
It thus will be seen that the objects and advantages of this invention have been fully and effectively achieved. It will be realized, however, that the foregoing specific embodiment has been disclosed only for the purpose of illustrating the principles of this invention and is susceptible of modification without departing from such principles. Accordingly, the invention includes all embodiments encompassed within the spirit and scope of the following claims. | Improvements to the M60 7.62-mm machine gun (1) to enable it to be cocked after the cover assembly has been closed without opening the latter (2) to minimize the possibility of a runaway gun (3) to enable a hot barrel to be changed without the necessity of using protective hand coverings (4) to eliminate the necessity of providing a bipod support assembly for every spare barrel (5) to provide for better control of the gun when firing from a standing position and (6) to simplify the construction of the gas cylinder and piston. | 5 |
BACKGROUND OF THE INVENTION
The present invention refers to a method and apparatus of cleaning fibrous material which is fed in the form of a sliver to an opening roller and is opened into individual fibers and, subsequently, fed to an open-end spinning device.
In known opener units of preparatory machines in spinning mills, the coarse impurities such as leaf, stalk and seed-kernal residues are largely removed and eliminated by beating action upon the cotton flock. But in that case, there is effected not only elimination but also partial smashing of these bits, whence arise particles of 300μ and smaller, which cling to the fibers again as microscopic dust. Hence, the fibers remain burdened with considerable amounts of microscopic dust, the greater proportion of which amounts to 150μ or is still finer (Melliand Textilberichte August 1976, pages 609 to 613).
With open-end spinning devices, the practice is known of loosening the sliver as far as single fibers, and in this form, leading it past a trash separator opening which exhibits a separator edge (West German O/S No. 1 914 115). For avoiding loss of fibers, an airstream directed against the direction of flight of the dirty matter is introduced into the fiber-air stream led to the spinning rotor. Dirty matter which is just as light or even lighter than fibers is held back by this infed flow of air just like the fibers and arrives with the fibers in the spinning rotor. Here the fine dust is deposited on the rotor wall and in the collector groove and interfers with the spinning operation. The shape of the groove is continually altered and the spinning process disturbed, whereby yarn breakages arise.
SUMMARY OF THE INVENTION
The above problem is minimized in accordance with the present invention by subjecting the fibrous material to the action of the beater roller and to a flow of air sucked outwards with respect to the beater roller, while the fibrous material is carried circumferentially to the beater roller. Through the high acceleration of the fibers in the region of the beater roller, the fibers are subjected by the roller lining to a high mechanical stress. Large amounts of microscopic dust are thereby rubbed off the surface of the fibers and the fragments of the fiber present in the mass of fibers are released. This fine, dirty matter gets carried away by the suction air flow while the fibers are carried in the direction circumferential to the beater roller and thereby held back.
Preferably, the fibrous material is still retained as a fiber tuft while the flow of suction air is acting on it. By this means, the separative action is still more intensive since the very fine dust gets eliminated in the region in which it gets separated from the fibers, before it can settle between the fibers afresh and have to be loosened out of the fibers once more by the lining/fiber, guide/fiber, and fiber/fiber friction.
In accordance with the invention, for performance of the method, a dust-separator opening is connected to a source of suction air provided between a delivery device and the open-end spinning machine in the wall of the housing surrounding the beater roller, and is provided with a gauze-like covering over which the fibrous material is carried past during the opening process, so that it is kept by the covering within the effective range of the beater roller. Advantageously, the dust-separator opening lies moreover in the region of the fiber tuft. In order to take into account the rapid motion of the dirty matter to be eliminated in the direction circumferential to the opening roller, the dust-separator opening advantageously extends in the direction of the free end of the fiber tuft to beyond it. In order to avoid sucking back into the fiber-air flow, of the very fine dust already eliminated, the dust-separator opening extends by less then 50 percent of the average fiber length beyond the free end of the fiber tuft.
In accordance with a preferred embodiment of the invention, the covering is arranged in continuation of the wall of the housing. In that case, the housing is advantageously provided with a lining which in the region of the dust-separator opening is made as a gauze-like covering.
Depending upon the fibrous material being processed, the dust to be eliminated differs in its character. It is, therefore, advantageous if for adaptation to the kind of material to be processed the covering can be exchanged. The covering may, in that case, extend around to the nip of the delivery device, in which caase in constructing the delivery point as a delivery roller with associated feeding trough at least one part of the covering may be made as an integral component of the feeding trough.
The dust-separator device in accordance with the invention may be used by itself or in connection with a trash-separator opening having a separator edge. In the latter case, the trash-separator opening is provided with a separator edge and follows the dust-separator opening.
For improvement of the conveyance of the fiber from the delivery device to the fiber feed channel, especially after the dust-separator opening in accordance with a further feature of the invention, there is provided in the wall of the housing an air supply opening which with respect to the direction of conveyance of the fiber is before the dust-separator opening. In order to compensate for the proportion of the air sucked away at the dust-separator opening an air supply opening can also be arranged after the dust-separator opening, which is advantageously made as a trash-separator opening.
A porous or perforated partition in the wall of the housing opposite to the periphery of the beater roller in the region of the fiber tuft is indeed already known, which separates the interior of the housing from a suction chamber (West German O/S No. 2 134,342). But this partition, together with the air flow acting upon the fiber tuft through it, has the object of raising the fiber tuft from the beater roller while the spinning device is standing still. Accordingly, it is not a dust-separator opening, since the suction air is not effective during operation of the spinning device. Furthermore, the fibers do not get conveyed along this partition during the opening process but get retained here after raising out of the effective range of the opening roller. A device is furthermore known (Japanese Patent As No. 23 773/71) by which means of a perforated partition too early action of the beater roller upon the fiber tuft is prevented. In the region of this perforated partition, the fiber tuft is not subjected to the action of the beater roller.
A porous partition is likewise known through the West German O/S No. 2 108 254. Air is, however, not sucked through this partition but, on the contrary, fed into the fiber/air flow.
Again, a trash-separator opening equipped with grate bars is known, which on the side remote from the opening roller is screened by a gauze (West German O/S No. 2 038 059, FIGS. 10 to 12). But such a device in a very short time clogs with dirty matter and is then no longer able to work since it does not keep the fibrous material in the effective range of the beater roller and, hence, no fibers get carried past across it, which might clean this gauze again.
An air-permeable feeding trough is already known (Czech Pat. No. 144 745). But air is led in and not out through the air-permeable portion of the feeding trough. Furthermore, in this case, it is not a matter of the covering over a trash-separator opening.
By the device in accordance with the invention, not only are particles of dust and small fragments of fiber arising in the earlier working runs led away, but also the particles of dust and small fragments of fiber which arise during the opening process in the beater device itself are removed. In this way, a considerable reduction in yarn breakages is achieved.
Accordingly, it is an important object of the present invention to provide a method and apparatus which enables fine, dusty matter contained in fibrous material to be separated therefrom.
Another important object of the present invention is to provide a device for separating dust from fibrous material as it is fed round a beater roll for being spun in an open-end spinning device.
These and other objects and advantages of the invention will become apparent upon reference to the following specification, attendant claims, and drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side elevational view, partially in section, illustrating an open-end spinning device equipped with a fine dust separator constructed in accordance with the present invention;
FIG. 2 is a side elevational view, partially in section, of a modified form of the invention wherein a dust-separator device is positioned outside the region of the fiber tuft;
FIG. 3 is a side elevational view of still another modified form of the invention wherein a gauze-like covering is shown positioned over a dust-separator opening and is defined by a portion of a feeding trough and by a portion of the wall of the housing;
FIG. 4 is still another modified form of the invention in which a dust-separator device is an integral component of the feeding trough.
FIG. 5 illustrates still another modified form of the invention wherein the dust-separator device is positioned beyond a trash separator device provided in the wall of the housing surrounding a beater roll;
FIG. 6 is a sectional view illustrating still another modified form of the invention wherein an air supply opening is positioned in the wall of the housing following a dust-separator device.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The fibrous material is fed in the form of a sliver 1 through a feed device 2 of an opening roller 3. The feed device 2, which in principle may be otherwise constructed, exhibits in accordance with the embodiment shown in FIG. 1 a delivery roller 20 and a feeding trough 21 cooperating with it. The front end of the sliver 1 which forms a fiber tuft 10 is opened by the opening roller 3 into individual fibers 11 and, in this form, is fed through a fiber feed channel 4 of a spinning chamber 5. The particular form of the spinning chamber is without interest to the present invention. Thus, the spinning chamber 5 may be constructed for example, as a spinning rotor, as shown, but also as an open-end spinning chamber operating electrostatically or pneumatically or in any other way. The fibrous material is drawn out of the spinning chamber 5 in the form of a yarn in a known manner (not shown).
The opening roller 3 is surrounded by a housing 30 which is provided with a wear-resistant lining 34 which exhibits the necessary openings 340 and 341 for the feeding of the sliver 1 to the opening roller 3 and for the removal of the fibers 11 into the fiber feed channel 4.
In the housing 30 between the delivery device 2 and the feed chamber 5, a dust-separator opening 6 is provided which is covered by a gauze-like covering 72. The gauze-like covering 72 is an integral component of the lining 34 while the dust-separator opening 6 is provided in the feeding trough 21. The feeding trough 21 is pressed by a first compression spring 210 against the delivery roller 20 and by a second compression spring 211 against the lining 34 to make a seal.
A pipe connection 81 is provided for the feeding trough 21 and is connected to the dust-separator opening 6. A hoselike channel 8 is connected to the pipe connection. A source of suction air 82 is connected to the channel 8 via a filter 80.
The fibrous material is fed to the opening roller 3 in a known manner in the form of a sliver 1 by means of the delivery device 2. The fibers 11 are opened out of the front end of the sliver 1 by the opening roller 3 and are carried between the opening roller 3 and the lining 34 in the direction of the arrow to the fiber feed channel 4, via which they arrive in the spinning chamber 5 for spinning. The fibers make their way to the fiber feed channel past the dust-separator opening 6 while being kept by the covering 72 in the effective range of the opening roller 3.
Through the rubbing of the fibers 11 against the teeth of the lining of the opening roller 3, through the rubbing of the fibers 11 on one another, and through the rubbing of the fibers 11 against the lining 34 and against the covering 72, the microscopic dust gets rubbed off the surface of the fibers 11. In the region of the covering 72, the fibers 11 are subjected to a flow of air acting through the covering 72. The fine dust rubbed off the fibers 11 is thereby sucked out and carried away. Advantageously, the dustladen air sucked away via the channel 8 is carried away via a filter 80 and purified.
On the side next to the opening roller 3, the gauze face of the covering 72 is kept free by the fibers 11 sliding over it. The outside of the covering 72 remains free of deposits through the constant sucking away of the microscopic dust.
The dust-separator device, in accordance with the present invention, may also be used in combination with a trash-separator device for coarser particles, which exhibits a trash separator opening 9 and a separator edge 90. The construction of the trash separator device and its arrangement in the path of conveyance of the fibers is without interest to the present invention. If the housing 30 is provided with a lining 34, an opening 342 is provided therein for the trash-separator device. The device in accordance with the invention may be constructed in various ways. Thus, it is possible to provide the dust-separator opening 6 at any point in the wall 31 of the housing between the delivery device 2 and the fiber feed channel 4 (FIG. 2). The dust-separator opening 6 is covered over in continuation of the wall 31 by a gauze-like covering 7 which is fitted into the housing 30 in such a way that between the cover 7 and the wall 31, there is no projecting edge at least in the direction of conveyance as indicated by the arrow 32, against which the fibers 11 could get caught or packed together. The gauze-like covering 7 may, in that case, form part of the housing 30 in the form, for example, of a lining (FIG. 1) and/or be replaceable.
By changing the covering 7, adaptation is possible to the particular fibrous material being admitted for spinning. By appropriate selection of the width of mesh of the covering 7, the removal of microscopic dust being striven for is possible.
The width of mesh of the coverings 7 and 72 is so dimensioned that the dust escapes in the way desired, but the fibers 11 are guided past and not impeded in their motion of conveyance.
The conveyance of the fibers 11 in the direction towards and into the fiber feed channel 4 is effected by a flow of air. Since air is sucked away through the channel 8, it may be advantageous if an air supply opening 37 (FIG. 6) follows after the covering 7 or 72 over the dust-separator opening 6 in the direction of conveyance of the fiber. If, in accordance with FIGS. 1 and 3 a trash-separator opening 9 is provided, this opening 9 may take over the function of the air supply opening since the separation of the coarse dirty matter is effected against the flow of air being fed in here.
As shown in FIGS. 1, 3 and 4, the dust-separator opening 6 preferably lies in the region 33 of the housing 30 surrounding the opening roller 3, in which the fibers 11 are opened out of the fiber tuft 10 from the sliver 1 being held back by the delivery device 2.
While the fibers 11 are still getting held back by the delivery device 2, the dusty matter is getting stripped off the fibers 11 by lining/fiber, fiber/fiber and fiber/covering friction and immediately carried away by the flow of suction air. Thereby, the components of the dust released from the fibers 11 cannot settle on the fibers 11 afresh.
The fibers 11 are conveyed in the direction of the arrow 32 in a flow of air between the opening roller 3 and the wall 31 of the housing or the lining 34 to the spinning chamber 5. This flow of air arises through the rotation of the opening roll 3.
The flow of air is further strengthened for the second time if the spinning chamber 5 is of such a construction that reduced pressure is needed for spinning. Taking into consideration the flow through the spinning air system, the effective dust-separator opening 6 over which the coverings 7 and 72 extend is so dimensioned that it extends not only under the fiber tuft 10 but also even beyond. In this way, the fine dust released from the fiber tuft 10 is safely carried away under the action of the flow of suction air acting in the channel 8. But the covering 7 or 72 should not project beyond the fiber tuft 10 by more than 50 percent of the average length of fiber. If the covering 7 or 72 projects beyond the fiber tuft 10 by more than 50 percent of the average length of fiber with increasing length of the covering 7 or 72, the danger becomes ever greater that the fine dust already sucked away can get sucked back into the fiber-air flow being carried in the direction of the arrow 32. This increases the danger of the fine dust settling in the spinning chamber 5 and leading to spinning trouble.
A flow of air conveys the fibers 11 over the dust-separator opening 6. Depending upon the strength of the flow of air sucked away through the channel 8, it may therefore be advantageous if an air supply opening 36 is provided before the dust-separator opening 6 (FIGS. 2 and 3).
As shown in FIG. 3, one part 22 of the feeding trough 212 may be made as a gauze-like covering, so that at least one part of the covering is an integral component of the feeding trough 212. If the covering 7 extends round underneath the gauze-like part 22 of the feeding trough 212 the covering 7 in this region exhibits a larger opening 70 in order to avoid clogging of the covering 7.
The feeding trough 21 may also be extended in the direction circumferential to the opening roller 3 and its end which extends from the nip 23 between the delivery roller 20 and the opening roller 3 forms a covering 73. This end is made gauze-like. The channel 8 is connected to a source 82 of suction air ending underneath part 22 of the feeding trough 21.
The feeding trough opening 35 in the housing 30 as illustrated in the embodiment shown in FIG. 4 is larger than usual since it includes the dust-separator opening 6. The feeding trough opening 35 is covered over from the inside of the housing by a diaphragm 24 which is connected to the feeding trough 21. The wall 31 of the housing is separated radially from the opening roller 3 further than usual. The inner face 240 of the diaphragm 24, however, is arranged at such a gap from the opening roller 3 that it still keeps the fibers 11 within the effective range of the opening roller 3. The dust-separator opening 6 is again arranged in the feeding trough 21 as in the case of the embodiment shown in FIG. 1. In contrast to the embodiment of FIG. 1, the feeding trough is pressed outwards by the compression spring 211 so that the diaphragm 24 is held in contact with the wall 31.
Operation of a device of this kind is the same as described above. In an embodiment of this kind (just as the embodiment of FIG. 1), it is advantageous for uniform opening of the sliver 1 that a long support for the fiber tuft 10 be provided.
The sucking away of the fine dust released is effected both in the circumferential direction outwards and also to the sides. In accordance with FIG. 3, a space (not shown) at the side of the opening region 33, likewise connected to the channel 8, is covered over by a gauze-like covering 71. Hence, the sucking away of the fine dust released from the fibers 11 is effected out of the sides, too.
As the preceding description shows, the device in accordance with the invention may be made in various ways and also be combined with a trash-separator device as known hitherto. The channel 8 may be connected directly or indirectly via an intermediate space (not shown) to the covering 7. Depending upon the feed of fiber and the degree of impurities, it may be advantageous if the reduced pressure in the channel 8 is controllable. The filter 80 may also be made as a simple filter or as a fairly large filter installation.
As explained in connection with FIG. 2, for the object of the invention, it plays no part in principle where on the path of conveyance the covering 7 of the dust-separator opening 6 is arranged. Hence, it is also possible to provide a dust-separator device if a trash-separator opening 91 is arranged in the direct neighborhood of the feed device 2 (FIG. 5). In this case, the dust-separator opening 6 is provided in the shell of the housing 30 between the trash-separator opening and the start of the fiber feed channel 4.
The present description shows that the object of the invention may be modified in many ways. The common feature of all embodiments is that the sliver 1 is guided in the region of influence of the opening roller 3 over a gauze-like surface, the coverings 7, 70 or 72 respectively, while at the same time, it is subjected to a flow of suction air directed outwards with respect to the opening roller 3. | A method and apparatus for cleaning fibrous material which is fed in the form of a sliver by a delivery device to an opening roller carried within a housing which opens the fibrous material and feeds the opened fibers to an open-end spinning device. A dust separator opening is provided in the housing between the delivery device and the open-end spinning device. A source of suction is connected to the dust-separator opening and a gauze-like covering extends over the dust-separator opening for maintaining the fibrous material within the effective range of the opening roller as the fibrous material is carried thereover during the opening process. The dust from the fibrous material is withdrawn through the gauze-like covering and the dust-separator opening by the source of suction. The housing can also be provided with a trash separator opening having a separator edge positioned adjacent thereto for separating trash from the fibrous material simultaneously while the dust is being removed therefrom. | 3 |
BACKGROUND
Field of the Technology
[0001] The present invention relates generally to toilet sanitation. In particular, the invention relates to anti-splash devices for conventional toilets in CPC E03D 9/00, sanitary or other accessories for lavatories, and CPC A47K 13/26, mounting devices for seats or covers.
[0002] Conventional floor toilets, typically constructed of porcelain or a similar material, are a receptacle having a floor-mounted, bowl-shaped collection basin with a pool of standing water in the basin. A drain is typically placed at the bottom of the basin below the pool of standing water. The interior walls of the basin and the standing water provide an area to receive a stream of urine from a person using the toilet. When the toilet is flushed, water runs down and along the interior walls and the standing water, along with the urine, exits through the drain. Fresh water then replaces the flushed fluids to create another pool of standing water for future use.
[0003] The porcelain construction of toilets means that it has hard-surfaced walls. These hard surfaces reflect or deflect some portion of any urine stream directed thereon, splashing droplets of urine away from the point where the urine stream impacts the surface. Further, a urine stream directed into the standing pool of water in the basin will also cause splashing, in this case in the form of a urine-water mixture.
[0004] This splash back is a long-recognized problem and can occur regardless of whether the urine stream first contacts the surface of the water or the interior wall of the collection basin.
[0005] Several functional solutions to the problem of splash back in conventional toilets have been attempted. Past solutions suffer from having either small targets making use of the solution difficult or prevent the use of the toilet for solid waste making the solution inconvenient. Accordingly, there is a continuing need for an alternative conventional-toilet splash-back device that is convenient, effective, and practical.
BRIEF SUMMARY
[0006] The illustrated embodiments of the invention include an apparatus for attenuating reflective splash during the use of a conventional toilet. The apparatus includes a base that includes a plurality of upstanding, retractable baffles. The base, lying against the interior surface of the basin, has an appropriate thickness so that the flow of water down the interior walls of the basin during the flushing process is unobstructed. Additionally, the base, made of a flexible sheet material which is wrapped into a frustoconical form and laid on the interior surface of the toilet bowl, has perforations defined therethrough to prevent the collection of fluid on the surface of the base while still conforming to the contours of the interior surface of the basin. A central opening, defined by the base, exposes the pool of standing water below it and allows for, in addition to the retractable baffles, the operation of the toilet for solid waste without the need to remove the apparatus. The conical shape of the base prevents the base from sliding down into the lower portion of the basin. Rails run along both the upper and lower edges of the base providing rigidity and structure to the base.
[0007] In some embodiments, the base does not use the rails along both upper and lower edges. This allows the base to maintain a flexible property and adapt to different toilet-bowl shapes.
[0008] In some embodiments, the base has a radial cut through the entirely of the thickness of the base, breaking the continuity of the base, to allow for temporary manipulation of the shape of the base to ease the installation process into the toilet.
[0009] In some embodiments, the base is suspended by hooks that attach to the rim of the toilet bowl while continuing to keep the base in close contact with the interior surface of the basin.
[0010] In accordance with the present invention, a plurality of hinges are disposed radially on the base. The hinges would rotate such that the baffles, in the non-operative configuration, would lie parallel to the surface of the base or the rails on the upper and lower edges of the base.
[0011] In some embodiments, the hinges are disposed in a radial fashion, but offset such that the hinges form a pinwheel-like pattern, or configuration, on the base.
[0012] In some embodiments, the hinges are disposed to form concentric circles where the hinges would rotate toward the central opening.
[0013] Also in accordance with the present invention, a plurality of upstanding baffles are disposed on top of the plurality of hinges. When the hinges rotate downward, the baffles are placed into a non-operational configuration and when the hinges rotate upward, the baffles are placed into an operational configuration. The plurality of baffles are substantially uniform or approximately equal in height, thickness, and flexibility.
[0014] In accordance with some embodiments, the baffles vary in length with a range of approximatelyl inch to 5 inches, thickness with a range of approximately 0.05 inches to 0.25 inches, and distance between baffles within a group of baffles.
[0015] In accordance with some embodiments, the distance between one group of baffles and another, has a range of approximately 0.25 inches to 1 inch so that the operation of the hinges do not cause interference with adjacent baffles.
[0016] In some embodiments, where the hinges are disposed in concentric circles, the hinges would vary in height with the taller hinges disposed on top of the base closer to the outer edge of the base and the shorter hinges disposed on top of the base closer to the inner edge of the base.
[0017] Also in accordance with the present invention, a plurality of stoppers are disposed adjacent to the plurality of hinges such that the stoppers and hinges are paired together. The stopper prevents the hinge from rotating beyond 90 degrees.
[0018] Also in accordance with the present invention, a plurality of rods are disposed within the hinges such that a single rod is disposed within a single hinge. The rod is disposed within the hinge such that the length of the rod runs along the length of the hinge. The exposed end of the rod, facing the outer edge of the base, has an eyelet.
[0019] Also in accordance with the present invention, a cable is threaded through each eyelet and secured to each eyelet. When the cable is pulled in one direction, the hinges will rotate and position the baffles in a non-operative configuration. When the cable is pulled in an opposing direction, the hinges rotate oppositely and position the baffles in an operative configuration. The operative configuration includes a configuration where the plurality of baffles are rotated from an angular orientation lying flatly along the interior surface of the toilet to an angular orientation elevated above the inner toilet surface. The intended or preferred fully operative configuration is that one where the plurality of baffles are rotated to an angular orientation wherein they extend generally radially into the central opening of the toilet, but any orientation bringing the baffles out of they flat disposition against the inner surface of the toilet will be operative to a degree.
[0020] Also in accordance with the present invention, a spring is attached to one end of the cable. The cable, affixed to the base, provides constant tension such that the baffles are normally disposed into a non-operative configuration.
[0021] Also in accordance with the present invention, overcoming the tension in the spring pulls the cable so that the baffles rotate into an operative configuration.
[0022] In accordance with some embodiments of the present invention, the cable is attached to the toilet seat. When the toilet seat is lifted, the cable is pulled overcoming the tension of the spring and rotating the baffles into the operative configuration. When the toilet seat is lowered, the baffles rotate into the non-operative configuration.
[0023] In accordance with some embodiments of the present invention, the trigger mechanism is a foot pedal disposed on the floor adjacent to the toilet. When the pedal is depressed and locked, the cabled is pulled and the baffles rotate into the operative configuration. When the pedal is released, the baffles rotate back into the non-operative configuration.
[0024] While the apparatus and method has or will be described for the sake of grammatical fluidity with functional explanations, it is to be expressly understood that the claims, unless expressly formulated under 35 U.S.C. §112, are not to be construed as necessarily limited in any way by the construction of “means” or “steps” limitations, but are to be accorded the full scope of the meaning and equivalents, and in the case where the claims are expressly formulated under 35 U.S.C. §112 are to be accorded full statutory equivalents under 35 U.S.C. §112. The disclosure can be better visualized by turning now to the following drawings wherein like elements are referenced by like numerals.
BRIEF DESCRIPTION OF THE DRAWINGS
[0025] FIG. 1 is an isometric view of a single hinge with the baffles coupled to the hinge in the operative configuration.
[0026] FIG. 2 is a side plan view of a single hinge with the baffles in the operative configuration
[0027] FIG. 3 is an isometric view of a single hinge with the baffles in the non-operative configuration.
[0028] FIG. 4 is a side plan view of a hinge with the baffles in the non-operative configuration.
[0029] FIG. 5 is top perspective view of the apparatus with a plurality of hinges coupled together with their corresponding baffles disposed in the operative configuration.
[0030] FIG. 6 is top perspective view of the apparatus with a plurality of hinges coupled together with their corresponding baffles disposed in the non-operative configuration.
[0031] FIG. 7 is a top perspective view of the apparatus with a plurality of hinges coupled together with their corresponding baffles disposed in the operative configuration within a conventional floor toilet.
[0032] FIG. 8 is a top perspective view of the apparatus with hooks that suspend the apparatus within the toilet.
[0033] FIG. 9 is a top perspective view of the base without the upper or lower rails and without the hinges, stoppers, or baffles with the radial cut through the base.
[0034] FIG. 10 is an isometric view of the hook that attaches to the toilet seat with the cable adhered to the hook.
[0035] FIG. 11 is a top perspective view of the apparatus disposed within a conventional toilet with the hook attached to the toilet seat.
[0036] The disclosure and its various embodiments can now be better understood by turning to the following detailed description of the preferred embodiments which are presented as illustrated examples of the embodiments defined in the claims. It is expressly understood that the embodiments as defined by the claims may be broader than the illustrated embodiments described below.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0037] FIG. 1 illustrates an aspect of one embodiment. Hinge 101 is a rotatable bar from which a plurality of finger-like baffles 102 extend. Baffles 102 may be integral with hinge 101 or each separately connected or attached to hinge 101 . Hinge 101 is rotatable clockwise in FIG. 1 to dispose baffles 102 in a non-operative configuration shown in FIG. 3 and is rotatable counter-clockwise in FIG. 1 to dispose baffles 102 in an operative configuration, which is the configuration shown in FIG. 1 . Hinge 101 may include a rod (not shown) along its length that acts as an axle, adjacent and parallel to stopper 103 . Alternatively, hinge 101 could rotate on a pin (not shown) extending from each end of the stopper 103 . Stopper 103 is a bar with vertically extending flange 100 against which hinge 101 rotates and which serves to stop further counter-clockwise rotation from that shown in FIG. 1 . Stopper 103 prevents hinge 101 from rotating beyond an angular orientation corresponding to the extension of flange 100 as best depicted in the side plan view of FIG. 2 . Hinge 101 and stopper 103 are preferably composed a substantially rigid plastic. In one embodiment baffles 102 are disposed on top of hinge 101 through holes (not shown) on top of the hinge 101 and adhered within the hinge 101 .
[0038] Eyelet 104 provides a location where a cable 105 may attach. Eyelet 104 is disposed on or extends from an end of hinge 101 . The cable 105 rotates hinge 101 in either clockwise or counter-clockwise directions depending on the direction of tension of the cable 105 . When the cable 105 pulls from the left in the depiction of FIG. 1 , the baffles 102 are disposed in the non-operational configuration shown in FIGS. 3 and 4 . Due to the offset of eyelet 104 from the pivot point where hinge 101 is rotatably coupled to stopper 103 , the cable 105 pulls from an elevated angle or lever arm relative to the pivot point. This angle allows for the cable 105 to pull the hinge 101 and baffles 102 upward into the operative configuration of FIGS. 1 and 2 . When the cable 105 pulls from the right as depicted in FIG. 1 , the similar but opposite action occurs to dispose hinge 101 and baffles 102 into the nonoperative configuration of FIGS. 3 and 4 . Because the cable 105 is threaded or disposed through a base-mounted eyelet 106 shown in FIG. 5 , the cable 105 pulls on hinge 101 from a depressed angle to allow for the cable 105 to pull the hinge 101 and baffles 102 downward.
[0039] A plurality of hinges 101 with their corresponding baffles 102 are assembled to a plurality of upper base rails 107 and lower base rails 108 shown in FIGS. 5 and 6 . Upper and lower base rails 107 , 108 collectively form the base 110 . Each base rail 107 and 108 may be rigidly coupled to its corresponding stopper 103 and to the adjacent base rails 107 , 108 at each opposing end of each base rail 107 , 108 or may be flexibly coupled together by means of conventional flexible couplings (not shown). Therefore, continuing around the base rails 107 , 108 , the cable 105 is laid out concentrically in an in-and-out pattern in the depiction of FIGS. 5 and 6 . The cable 105 lies over the stopper 103 and through the eyelet 104 on the hinge 101 . In the illustrated embodiment of FIGS. 5 and 6 the upper end of hinge 101 is provided with eyelet 104 and upper base rail 107 is similarly provided with a base-mounted eyelet 106 through which cable 105 will be led. Alternatively, lower base rail 108 may have the eyelet 106 disposed thereon or extending thereform when eyelet 104 on hinge 101 is provided on the lower end of hinge 101 . Then the cable 105 is led concentrically in FIGS. 5 and 6 by being threaded throughbase eyelet 106 and this pattern repeats toward the adjacent hinge 101 and baffle 102 .
[0040] FIG. 5 illustrates an aspect of one embodiment. Baffles 102 are disposed in the operative configuration. Base 110 comprises a flexible material demonstrating some elasticity and contains perforations through the base to mitigate the collection of fluid on the base surface. Hinges 101 are fastened on the surface of base 110 either through adhesives, screws, or rivets. Central opening 114 exposes the pool of standing water (not shown) in the center of the toilet basin (not shown).
[0041] Baffles 102 will typically comprise a flexible material and vary in thickness and in length. Baffles 102 that are too long may cause more splash back due to the proximity of the baffles 102 to the upper rim of the toilet basin. Therefore, baffles 102 or varying lengths may typically be used where longer baffles 102 are disposed lower in the toilet basin and shorter baffles 102 are disposed higher in the toilet basin. Additionally, baffles 102 that are too thick may reduce the effectiveness of splash reduction. Therefore, the thickness of the baffles 102 would likely be smaller than the diameter of a typical urine stream.
[0042] During use, the urine stream will likely make contact with one of three different points: the baffles 102 , the surface of the base 110 , and the pool of standing water through the central opening 114 . When the urine stream strikes the water, splash-back is mitigated through the interference of the baffles 102 . As splash occurs, the baffles 102 interrupt the droplets' upward motion. When the urine stream strikes the surface of the base 110 , the reflective droplets are again interrupted by the nearby baffles 102 . Additionally, the perforations in the base 110 will mitigate the amount of the urine stream that makes contact at such an angle that produces droplets that would reflect outward. When the urine stream strikes a baffle 102 , the urine stream is broken apart and a majority of the stream is fanned out. The fanning-out process produces the benefit of decelerating the urine stream as well as causing the urine stream to strike additional baffles 102 which will cause additional deceleration. Additionally, the amount of surface area by which outward-bound droplets form is reduced by the fact that the baffles 102 are cylindrically shaped including a rounded tip 116 .
[0043] A larger density of hinges 101 may be used. This would reduce the amount of exposed base surface during the urinating process.
[0044] The position of the baffle 102 on each hinge 101 may be placed in a staggered formation to ease the transition to the non-operational configuration. A staggering of the baffles 102 may help the baffles 102 retract more compactly.
[0045] FIG. 6 illustrates an aspect of one embodiment. Baffles 102 are disposed in the non-operative configuration. A spring 111 is affixed to one end of the cable 105 . The other end of the spring 111 is affixed to the base 110 . The spring 111 provides a persistent tension pulling the hinges 101 and baffles 102 into the non-operative configuration. Perforations 118 provide a bore through base 110 .
[0046] FIG. 7 illustrates an aspect of one embodiment. The apparatus is disposed within toilet 120 with baffles 102 disposed in the operative configuration.
[0047] FIG. 8 illustrates an aspect of one embodiment. Hooks 119 provide a suspension mechanism for the apparatus when disposed within the toilet.
[0048] FIG. 9 illustrates an aspect of one embodiment. Base 110 comprises of a flexible sheet material with a radial cut through base 110 . Perforations 118 provide a bore through base 110 . Central opening 114 exposes the pool of standing water within the toilet when base 110 is disposed along the inner-toilet surface.
[0049] FIG. 10 illustrates an aspect of one embodiment. Hook 125 , comprising of a substantially rigid material, attaches to the toilet seat. Cable 105 is adhered to hook 125 .
[0050] FIG. 11 illustrates an aspect of one embodiment. The apparatus is disposed within toilet 120 with baffles 102 in the non-operative configuration. Cable 105 is adhered to hook 125 and hook 125 is attached to the toilet seat of toilet 120 . When the toilet seat is lifted, tension is provided in cable 105 which transitions baffles 102 from the non-operative configuration to the operative configuration shown in FIG. 7 .
[0051] Many alterations and modifications may be made by those having ordinary skill in the art without departing from the spirit and scope of the embodiments. Therefore, it must be understood that the illustrated embodiment has been set forth only for the purposes of example and that it should not be taken as limiting the embodiments as defined by the following embodiments and its various embodiments.
[0052] Therefore, it must be understood that the illustrated embodiment has been set forth only for the purposes of example and that it should not be taken as limiting the embodiments as defined by the following claims. For example, notwithstanding the fact that the elements of a claim are set forth below in a certain combination, it must be expressly understood that the embodiments includes other combinations of fewer, more or different elements, which are disclosed in above even when not initially claimed in such combinations. A teaching that two elements are combined in a claimed combination is further to be understood as also allowing for a claimed combination in which the two elements are not combined with each other, but may be used alone or combined in other combinations. The excision of any disclosed element of the embodiments is explicitly contemplated as within the scope of the embodiments.
[0053] The words used in this specification to describe the various embodiments are to be understood not only in the sense of their commonly defined meanings, but to include by special definition in this specification structure, material or acts beyond the scope of the commonly defined meanings. Thus if an element can be understood in the context of this specification as including more than one meaning, then its use in a claim must be understood as being generic to all possible meanings supported by the specification and by the word itself.
[0054] The definitions of the words or elements of the following claims are, therefore, defined in this specification to include not only the combination of elements which are literally set forth, but all equivalent structure, material or acts for performing substantially the same function in substantially the same way to obtain substantially the same result. In this sense it is therefore contemplated that an equivalent substitution of two or more elements may be made for any one of the elements in the claims below or that a single element may be substituted for two or more elements in a claim. Although elements may be described above as acting in certain combinations and even initially claimed as such, it is to be expressly understood that one or more elements from a claimed combination can in some cases be excised from the combination and that the claimed combination may be directed to a subcombination or variation of a subcombination.
[0055] Insubstantial changes from the claimed subject matter as viewed by a person with ordinary skill in the art, now known or later devised, are expressly contemplated as being equivalently within the scope of the claims. Therefore, obvious substitutions now or later known to one with ordinary skill in the art are defined to be within the scope of the defined elements.
[0056] The claims are thus to be understood to include what is specifically illustrated and described above, what is conceptually equivalent, what can be obviously substituted and also what essentially incorporates the essential idea of the embodiments. | Described herein is an apparatus mitigating splash-back during the use of a conventional toilet while urinating. The apparatus uses a plurality of upstanding baffles that provide for a large target area mounted on a base with a central opening. Additionally, the baffles rotate into and out of operative configurations, relative to the inner-toilet surface, to allow the use of the toilet for solid waste. The baffles mitigate the effect of splash back as the urine stream makes contact with the baffles and reflects the droplets laterally. Additionally, droplets generated when the urine stream contacts either the base or pool of standing water is mitigated by the baffles intercepting the reflective path back to the user. | 4 |
BACKGROUND OF THE INVENTION
This invention relates to an insulating enclosure for a ceiling opening, and more particularly, to a cap-like enclosure for a ceiling opening of the kind associated with a pull-down folding stair.
As is well known, pull-down folding stairs are often used for access, in homes or other building structures, to overhead areas such as attics or the like. Typically, such stairs fold or retract upwardly into a frame secured between the joists of the structure, and the folded stairway is covered when so retracted by a panel associat,ed with the ceiling. Folding stairs of the foregoing type are favored for use in connection with areas to which access is only occasionally required, because, unlike conventional fixed stairways, folding stairs take up no floor space.
It has been found that folding stairs and the enclosures in which they are typically mounted are difficult to insulate, and can account for relatively high heat losses. This is so because the area of the frame into which the stair folds, unlike surrounding areas between structural joists and above ceilings, is devoid of insulation. The thin cover panel usually associated with the stair provides little resistance to heat loss by radiation, conduction or convection. The problem is made more acute in situations in which the ceiling with which the stair is associated divides an inhabited, and therefore heated or cooled, space, and a space which is not temperature controlled or is in communication with ambient atmospheric conditions.
It has also been observed that the nature and construction of folding stairs makes it difficult to insulate such stairways merely by adding conventional insulation. Because it is necessary to have access through the ceiling opening in which the stair is mounted, conventional roll insulation cannot readily be used. Moreover, insulation lying above the stair and the ceiling opening would creates difficulties with access to the overhead space, and is not, in any event, particularly effective. One reason for this is that in the folded position, the stair mechanism usually extends well above the floor line. Therefore, a simple blanket of insulation, laid over the opening, is ineffective, because the stair mechanism lifts the blanket from the floor when the stair is closed.
In view of the above, it has heretofore been proposed to provide insulating caps or covers for folding stairs. In this regard, U.S. Pat. No. 4,281,743, issued Aug. 4, 1981, to George C. Fuller suggested an insulating enclosure, fabricated in several embodiments from foamed plastic polymeric material, held together by tongue and groove joints.
U.S. Pat. No. 4,312,423, issued Jan. 26, 1982, to Earl G. Helbig, suggested the use of foamed material as an internal liner for an insulating cap, the cap itself being made of corrugated paper or other suitable material. In U.S. Pat. No. 4,344,505, issued Aug. 17, 1982, to Waters et al., it was proposed that an insulating cap be made of expanded polystyrene, the top of the cap being a slab-like member, hingedly secured to a rectangular frame.
U.S. Pat. No. 4,151,894, issued May 1, 1979, to Robert A. Edwards, suggested a rigid insulating cap, provided, however, with wheels to facilitate its rolling removal from the area around the ceiling opening.
Other insulating enclosures, caps or devices are illustrated in U.S. Pat. Nos. 2,321,499, issued June 8, 1943 to Marschke; 4,299,059, issued Nov. 10, 1981 to Smith; and 4,337,602, issued July 6, 1982 to King.
Prior art arrangements have generally, once installed, been made up of one large unit, requiring substantial additional head room and/or floor space to accommodate the cap or cover in its open position. By contrast, the present invention requires no additional floor space, and, in a presently preferred embodiment, needs only twenty-six inches (26") of headroom over the opening.
BRIEF DESCRIPTION OF THE INVENTION
It is, accordingly, a principal object of this invention to provide an insulating enclosure which is simple, inexpensive and effective, and which may be made from readily available and easily worked materials.
It is another object to provide an insulating enclosure constructed from modular elements, and which, by reason of its construction, provides easy access through the opening when access is desired.
Other objects will appear hereinafter.
The foregoing and other objects of this invention are realized, in a presently preferred form of the apparatus, by an insulating enclosure which comprises a wall portion, disposed around the periphery of the opening with which the enclosure is associated, and a removable top-forming member, which comprises plural panels, articulated in edge-to-edge fashion, providing a top for the enclosure. The wall portion, in the presently preferred from of the apparatus, includes a fixed portion, secured around part of the periphery of the opening and another portion secured to the top forming member, displaceable with the top forming member when access through the opening is desired. When the top-forming member is operatively disposed, the wall portion associated with the top-forming member and the wall portion secured arounu the periphery of the opening form a substantially continuous peripheral wall, and the wall and the top member, taken together, form a substantially continuous enclosure.
The top member and its associated wall portions are so arranged that the top member may be displaced to a stable "open" position wherein the enclosure is configured for access through the ceiling opening. Further, two wall portions secured around the periphery of the opening may be arranged for displacement from their operative, wall-forming position, to provide further ease of passage through the opening.
In presently contemplated forms of the invention, the wall portion and top-forming member are made from easily worked, readily available and relatively inexpensive materials. For example, in a presently contemplated form of the apparatus, the modules which make up the wall portion and the panels which make up the top-forming member comprise die-cut corrugated cardboard skins, assembled around insulating cores of plastic polymeric foam. The modules may be interconnected at various places by tabs extending from the modules and staples, some of the tabs providing hinges, and some of the connections being fixed or rigid. In some instances, staples alone may be used to interconnect the modules, and certain of the connections between the structural members may be effected by tabs and cooperating slits.
For the purpose of illustrating the invention, there is shown in the drawings a form of the invention which is presently preferred. It should be understood, however, that the invention is not limited to the precise arrangements and instrumentalities shown.
DESCRIPTION OF DRAWINGS
FIG. 1 is a side elevation view, in longitudinal cross-section, showing apparatus in accordance with the present invention and the manner in which it cooperates with a ceiling opening.
FIG. 2 is a cross-sectional view, taken along the line 2--2 in FIG. 1.
FIG. 3 is a partial view, in perspective, showing a tab and slit used in the present apparatus.
FIG. 4 is a perspective view, showing the apparatus in an operative configuration, overlying and insulating a ceiling opening.
FIG. 5 is a perspective view, generally similar to FIG. 4, but showing the apparatus in an intermediate position, between the operative position shown in FIG. 4 and an open position.
FIG. 6 is another perspective view, also showing the apparatus in an intermediate position.
FIG. 7 is a perspective view, similar in its aspect to FIGS. 4 through 6, but showing the apparatus in a position permitting access through the ceiling opening.
FIG. 8 is a plan view of a blank which may be used to form the skin of a panel of the top-forming member of the apparatus.
FIG. 8a is a partial view, similar to FIG. 8, of another form of blank used to make panels for the top-forming member.
FIG. 9 is a plan view of a blank which may be used to make modules to be used to make members for the sides of the wall portions of the apparatus.
FIG. 10 is a plan view of a blank which may be used to make members to be used at the ends of the wall portion.
DETAILED DESCRIPTION
Referring now to the drawings in detail, wherein like reference numerals indicate like elements, there is seen in FIGS. 1, 3 and 4 an insulating enclosure designated generally by the reference numeral 10. The enclosure 10 is made up of assemblage of individual modular elements, forming, in general, a peripheral wall 12 and a top 14. The wall 12 and top 14, when operatively disposed as depicted in FIGS. 1, 2 and 4, form a continuous "cap" or enclosure for an opening, designated generally by the reference numeral 16, in a horizontal partition (ceiling or floor) 18. For convenience, the horizontal partition 18 is hereafter referred to as a "ceiling" 18.
Referring to FIGS. 1 and 2, the ceiling 18 includes spaced parallel joists 20 and 22, between which cross braces 24 and 26 extend.
By way of illustration, disposed within the space defined by the joists 20 and 22 and the cross braces 24 and 26, and depicted in phantom in FIG. 1, is a conventional folded pull-down stair, designated generally by the reference numeral 28. The stair 28, it will be seen, includes articulated ladder sections 30, 32 and 34, hingedly interconnected so as to unfold, when desired, to provide a stair from the ceiling 18 to a floor (not shown) below it. A panel 36 is affixed to the ladder section 34 of the stair 28, and lies flush with the surface of the ceiling 18 when the stair 28 is retracted.
The wall 12 is made up of modular units, preferably of just two kinds. Referring to FIGS. 1 and 2, modules 38 form side walls or rails of the enclosure 10. Modules 40, somewhat different in their dimensions from the modules 38, form end walls or rails. In each instance, the modules comprise a "skin" member, designated generally by the reference numeral 42, enclosing a core, designated generally by the reference numeral 44, of insulating material. Preferably, the skin member 42 is made of corrugated board or other easily-worked material, and the core is made of closed-cell foamed polymeric material, such as the foamed polystyrene material, commercially available in block, sheet or bar form. In an alternative form of the invention, not shown, the skin member 42 may be plastic sheet or film.
Upon installation of the enclosure 10, certain of the modules 38 of the wall 12 are fixedly secured around a portion of the periphery of the opening 16. For this purpose, as is perhaps best seen in FIGS. 1 and 7, those modules 38 have extended flaps 46 which may be stapled or nailed, as at 48, to joists, such as the joist 20. Similarly, one of the modules 40 provides an end rail, which like the above-described modules 38, has a flap 50, which may be stapled or nailed, as at 52, to the cross brace 26. The side and end rails fixedly secured around the opening 16 provide a fixed wall portion, the purpose and operation of which will shortly be described.
The top 14 comprises, in the illustrated form of the apparatus, three panels 56, 58 and 60, hingedly interconnected at respective edges in accordian fashion. In this regard, referring to FIGS. 1 and 6, a hinge, formed by a flap 62 at a fold line adjacent the bottom edges of the panels 56 and 58, enables pivoting of these panels with respect to each other about a hinge line at their bottom edges. A hinge, formed by a flap 64, is disposed between the panels 58 and 60, at a fold line disposed adjacent the top surfaces of the panels 58 and 60. Thus, the panels 58 and 60 can rotate with respect to each other about a hinge line adjacent their respective upper faces. Alternatively, the hinges between the panels 56 and 58 and 60 may be formed by die-cut flaps (not illustrated) projecting from the panels, and stapled to the adjacent panel.
The panel 56 is also hingedly connected to the module 40, which provides an end rail, by means of tabs 66 (best seen in FIGS. 1, 6 and 3) which cooperate with slits 68 in the modular unit 40.
Referring to FIGS. 5 and 6, associated with the panel 60, but not secured to the ceiling 18, are wall-forming modules units 38 and an end-forming module 40. Such modules 38 and 40 may be secured to the panel 60 by tabs 70 and staples, or in other expedient ways, such as staples alone.
FIGS. 4 through 7 illustrate the manner in which the top 14 insulating enclosure 10 may be rearranged from an operative position, as illustrated in FIG. 4, in which it overlies and insulates an opening, to an open position, illustrated in FIG. 7, in which substantially free access may be had through the opening 16.
Referring first to FIG. 5, after the stair 28 has been pulled down from its stored position between the joists 20 and 22, a user may advance partly up the stair, and, by applying pressure to the underside of the panel 60 (at the front edge), cause the panel 60 and the associated modules (side rails) and module 40 (end rail) to pivot upwardly about the hinge defined by the tabs 64 approximately to the position shown in FIG. 5. Next, by applying pressure to the underside of the panel 58 near the flap 62, the panel 56 can be made to begin to rotate about the hinge defined by the tabs 66. Referring to FIG. 7, when the panels 56, 58 and 60 reach their ultimate folded position, the panel 60 with its associated modules 38 and 40 stand upright on the side rails defined by modules 38, but the top 14, in its entirety, is maintained above the side rails by the restraint provided by the tabs 66 in association with the slits 68. In other words, ultimately, abutment of the panels 56, 58 and 60 as the top 14 reaches its fully opened position, tends to prevent the top 14 from falling off or behind the side rails. As is evident from FIG. 7, the top 14, when in its folded or retracted position, obstructs the opening 16 only to the extent of the combined depth of the 60 and the module 40. In a presently contemplated form of the apparatus, this amounts to approximately 9 inches out of a total length of the opening 16 of approximately 41/2 feet.
Referring again to FIG. 7, access through the opening 16 may be further enhanced by, instead of securing the module 38' to the joist 22 in the manner of the other modules 38 and 40, securing the modules 38' to their adjacent side rail modules 38 by a hinge defined by a flap 72, positioned to form a hinge between each module 38' and its adjacent module 38. With such an arrangement, the user may, when passing thrbugh the opening 16, displace the module 38' from its alignment with its adjacent module 38, to reduce blockage caused by the side rail to a minimum.
Referring now to FIGS. 8 through 10, there are seen blanks from which the skin members 42 of the various modules may be made. Referring first to FIGS. 8 and 8a, a blank, designated generally by the reference numeral 74 provides one half of the skin member of each of the panels 56, 58 and 60. The blank 74 includes a panel face 76, separated by fold lines 78 and 80 from side flaps 82 and 94. A fold line 86 separates the panel face 76 from an end flap 88, provided, in the illustrated form, with construction tabs 90 and 92.
Folding of the side flaps 82 and 84 and the end flap 88 out of the plane of the panel face 76, and securing of the construction tabs 90 to the side flaps 82 and 84, by stapling, gluing or other suitable techniques, creates from the blank 74 an open-ended tray-like structure. Arcuate slits 94 in the side flap 82 define the above-mentioned tabs 66, so that the tabs 66 can be made to project from the fold line 78 upon folding of the side flap 82 with respect to the panel face 76.
Referring to FIG. 8a, a blank 74', slightly smaller dimensionally than the blank 74, but lacking the arcuate slits 94 providing for the tabs 66, supplies the remainder of the skin member 42 for the panels 56, 58 and 60. The tray-like members defined by the blanks 74 and 74', when fitted around a core 44 and nested into each other, form a substantially continuous skin member 42 for the panels 56, 58 and 60. Glue, tape or other suitable means may be used to effect the final assembly.
Referring now to FIG. 9, there is seen a blank, designated generally by the reference numeral 96 which may be used to form the skin member 42 of a typical side rail module 38. The blank 96 provides rail faces 98 and 100, the rail face 100 being separated by fold lines 102 and 104 from respective side flaps 106 and 108. The rail face 98 is separated by a fold line 110 from a side flap 112. Fold lines 114 and 116 separate the rail face 100 from respective end flaps 118 and 120. Similarly, fold lines 122 and 124 separate the rail face 98 from end flaps 126 and 128. Tabs 130 and 134 are separated by fold lines 136 and 138 from the side flap 108, and in a like manner, tabs 140 and 142 are separated by fold lines 144 and 146 from the side flap 112, together with a cut or punched out portion 150, adjacent to the slit 148, which permits manipulation of the blank 96 in a manner to be described. The slit 148, it will be appreciated, defines the above-described flap 46.
It should now be apparent that the blank 96 may be wrapped around a suitable core, such as the core 152 seen in cross-section in FIG. 2, and suitably secured by glue or other appropriate means, to form a side wall module 38.
Referring to FIG. 7, if it is desired that the module 38 serve as part of the fixed portion of the wall 12, the flap 46 may be made to extend from the rail face 98 as seen in this Figure, and also as in FIG. 1. In the case, however, of the module 38', which is not secured to a joist 20 or 22, the flap 46 remains folded about the fold line 110, so as to remain in the plane of the side flap 112.
Referring now to FIG. 10, there is seen a blank 154, which may be used to form the skin member 42 of an end rail forming module 40.
The blank 154 provides rail faces 156 and 158, separated, respectively, by fold lines 160 and 162 from a rail top flap 164. Separated from the rail face 158 by a fold line 166 is a rail bottom flap 168. End flaps 170 and 172 are separated by fold lines, of which fold line 174 is typical, from the rail face 158. Similarly, end flaps 176 and 178 are separated by fold lines, such as the fold line 180, from the rail face 156. Tabs 182 and 184 are separated by fold lines, such as the fold line 186, from the rail top flap 164.
Another bottom flap 188 is separated by a fold line 190 from the rail face 156, and a slit 192 in the flap 188 defines the above-mentioned flap 50, by which the finished end rail module 40 may be secured to a structural cross brace, such as the cross brace 26. A punched out portion 194 facilitates manipulation of the flap 50.
The above-mentioned slits 68, it will be seen, are formed along the fold line 162.
The blank 154 may be formed around a suitable core, such as the cores 196 and 198, seen in FIG. 1, to form finished modules 40.
An aspect of the manner in which the modules 40 may be joined to the modules 38, whether as part of the fixed wall 12 or of the top 14, is perhaps best seen in FIG. 6. Referring to that Figure, it will be noted in reference to the module 40 associated with the fixed wall 12 that the flap 172, like the flap 170 (hidden in this view) remains in the plane of the rail face 158 and creates, in effect, an extension of that face. Thus, the end flap 172 extends across an end face of the side rail module 38 adjacent to it, so as to provide a reasonably rigid joint and positive positioning of the modules 38 and 40 relative to each other. A piece of tape 200 or other convenient fastening means serves to secure the end flap 172 of the module 40 to the adjacent module 38.
Referring to FIGS. 5, 6 and 7, it will be seen that the module 40 associated with the top 14 is similarly interconnected to the modules 38 with which it is associated. Thus, referring to FIG. 7, the end flaps 170 and 172 of the module 40 extend across the end faces of the modules 38 with which the module 40 and the panel 60 are associated. In the case of the module 40 associated with the panel 60, the flap 50 is, in effect, retracted, and indeed, may advantageously be hidden above the uncut bottom flap 168.
Although the panel 60 obviously does not hinge with respect to the module 40 as does the panel 56 with respect to the module 40 affixed to the cross brace 26, the tabs 66 associated with the panel 60 may, when assembling the top 14, be inserted into the slits 68 in the module 40 for reinforcement and positioning purposes.
The present invention may be embodied in other specific forms without departing from its spirit or essential attributes. Accordingly, reference should be made to the appended claims, rather than the foregoing specification, as indicating the scope of the invention. | An insulating enclosure for a ceiling opening of the kind typically provided for a pull-down folding stair provides an inexpensive and simple structure for enclosing and insulating the opening. The structure comprises wall portions and a top portion overlying the wall portion when the apparatus is operatively disposed, the wall portions and top portions comprising modular insulating block-like members. The block-like members may be made of foam, encased in corrugated board or plastic sheet, interconnected by tabs or tape. | 4 |
This application is a 371 National Phase Entry Application of PCT/US2010/036979, with international filing date of Jun. 1, 2010, entitled “VIKING KNIT HAND TOOL”, which claims priority of U.S. Provisional Patent Application Ser. No. 61/217,622, filed Jun. 1, 2009 and entitled “Viking Knit All-In-One Tool” and which also claims priority of U.S. Provisional Application Ser. No. 61/336,370, filed Jan. 21, 2010 and entitled “Lazee Daizee Viking Knit Matrix Cone Tool”. The disclosures of these two provisional patent applications are incorporated herein by reference.
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates generally to the art and jewelry craft industry, and more particularly to a hand tool for making the Viking Knit weave from wire for use in art and jewelry pieces.
2. Related Art
Viking Knit is an old, traditional wire weave made by a looping technique of the wire around a cylindrical form such as a wooden dowel. The resulting woven wire tube is then gradually reduced in diameter by sequentially pulling the tube through a series of holes of diminishing diameters. Then the drawn Viking Knit is formed into jewelry and other decorative objects.
Methods for fabrication of traditional Viking Knit are centuries old, and have included the use of a solid, cylindrical form such as bone, wood in various sizes, wooden dowels, pencil shapes or more recently, even Allen wrenches. These items are most often attached to a stationary device such as a vise or clamp for ease of manufacture.
According to the prior art practice, before beginning the Viking Knit weave, a start-up bundle of wire loops must be constructed. This is a hand-formed, single-use group of looped wires than can be made by wrapping wire around a thin, solid form, approximately 1″ by ⅛″, to form loops that are then twisted or made stationary at one end. When the loose loops are parted they are shaped into a semi-flat flower petal-like form that is then bent over one end of the dowel, pencil or Allen wrench, and held in place by the wire shape itself, adhesive tape, additional wire or other means. The bent over form is then used as a base to begin the wire weaving process for the Viking Knit technique. Because the loose loops are not rigid, it can be difficult to get the Viking Knit weave started.
The prior art start-up bundle does not spin freely about a vertical axis as the Knit forms at the end of the dowel, pencil or Allen wrench. Later, the start-up bundle is used as a means of pulling the finished Viking Knit through a draw plate, a series of progressively smaller sized drilled holes, often made from a piece of wood. The Knit is drawn through increasingly smaller holes in the plate, allowing the Knit to reduce in diameter and increase in length. The start-up bundle is then cut away and discarded. Therefore, a new start-up bundle is created for each project.
New wire is added making a small hook at one end of the new wire or by inserting the new wire randomly into the existing Knit and holding it in place until the attachment is made following several additional stitches. An awl or other sharp, pointed instrument is used sometimes to lift the wire from the dowel, pencil or Allen wrench, whereby new stitching is created underneath. Also, preferably, the tool of the present invention is provided in a kit with a separate pointed instrument, like a thumb tack or push pin.
An example of one prior art device for making the Viking Knit is the kit currently advertised at CoolToolChick.com (http://www.cooltoolchick.com/viking.html).
SUMMARY OF THE INVENTION
This invention in one embodiment comprises a cylindrical rod with a rotatable and removable loop head inserted into the center of the top end of the rod. Preferably, the cylindrical rod is a hexagonal, nylon plastic rod. Alternatively, the rod may be dodecagonal. The loop head is made from, for example, a 6-loop Bali silver bead cap secured to the top of a rivet. Alternatively, the loop head may be molded from plastic with 6 or 12 outwardly, radially extending circumferential loops. The loop head is inserted into a vertical hole drilled into the top end of the rod, wherein the loop head is held by gravity, but able to spin or rotate freely in the hole. The vertical hole has an axis substantially parallel to, or even coincident with, the axis of the rod.
Preferably, the rod also has an anchor hole, drilled diagonally through the rod near its top end, for receiving and securing a wire. Also, preferably, the rod has indicia on its outer surface near its top, for indicating approximately the loop length in the first row of the Viking Knit. Metal wires, varying in size, most generally 32-18 gauge, copper-based, color coated wires and precious metal wires, are woven through the loop head and around the rod to form tubular Viking Knit stitches.
Preferably, the rod also has a conical wire wrap attachment at the bottom of the rod for making wired end caps to cover or enclose the finished Viking Knit weave. The conical wire wrap attachment has a hole drilled transversely through it near its bottom for receiving a wire.
Also, preferably, the tool of the present invention is provided in a kit with a separate draw plate for shaping and sizing the finished Viking Knit. The draw plate may be a sturdy, stiff plastic block with several holes of diminishing diameter drilled through it. The finished Viking Knit is sequentially pulled through several holes of diminishing diameter in order to better align the weave stitches and size the outer diameter of the weave.
In another embodiment, this invention comprises a hollow cone with a free-turning loop head inserted in either or both ends of the cone. Preferably, the hollow cone is hexagonal and/or dodecagonal. Also, preferably, the hollow cone has two rows of about 5/64 inch anchor holes about ½ inch apart, drilled into the cone on two sides thereof.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side, perspective view of one embodiment of the present invention in a hexagonal rod.
FIG. 2 is an exploded view of the embodiment depicted in FIG. 1 .
FIG. 3 is a side, perspective, detail view of the six (6)-loop head depicted at the top in FIG. 2 .
FIG. 4 is a side view of the embodiment depicted in FIG. 1 .
FIG. 5 is a cross-sectional view of the embodiment depicted in FIG. 4 , the section being taken along line 5 - 5 in FIG. 4 .
FIG. 6 is a side perspective view of the embodiment depicted in FIG. 1 , but with a first row of wire loops hanging from the loop head.
FIG. 7 is a side, perspective, detail view of the first row of wire loops depicted in FIG. 6 .
FIG. 8 is a side, perspective view of the embodiment depicted in FIG. 6 , but with an additional second row stitch of Viking Knit hanging from the first row of wire loops.
FIG. 9 is a side, perspective, detail view of the first row of wire loops and second row stitch of Viking Knit depicted in FIG. 8 .
FIG. 10 is a side, perspective view of the embodiment depicted in FIG. 8 , but with an additional third through twelfth rows of stitches of Viking Knit hanging from the first row of wire loops and second row stitch of Viking Knit.
FIG. 11 is a perspective, detail view of the loop head, first row of wire loops and 12 rows of stitches of Viking Knit depicted in FIG. 10 .
FIG. 12 is a perspective, detail view of the 12 rows of stitches of Viking Knit depicted in FIG. 10 .
FIG. 13 is a side, perspective view of another embodiment of the present invention in a dodecagonal rod.
FIG. 14 is an exploded view of the embodiment depicted in FIG. 13 .
FIG. 15 , is a side, perspective, detail view of the twelve (12)-loop head depicted at the top in FIG. 14 .
FIG. 16 is a top view of another embodiment of the present invention in a dodecagonal cone.
FIG. 17 is a side, perspective view of the embodiment depicted in FIG. 17 , with a six (6)-loop head in the small end of the cone, and with a twenty-four (24)-loop head in the large end of the cone.
FIG. 18 is an exploded view of the embodiment depicted in FIG. 17 .
FIG. 19 is a bottom perspective, detail view of the twenty-four (24)-loop head depicted at the bottom in FIG. 18 .
FIG. 20 is a top, perspective, detail view of the twenty-four (24)-loop head depicted in FIG. 19 .
FIG. 21 is a top view of another embodiment of the present invention in a twenty-four (24)-sided cone.
FIG. 22 is a side, perspective view of the embodiment depicted in FIG. 21 , with a six (6)-loop head in the small end of the cone, and a twenty-four (24)-loop head in the large end of the cone.
FIGS. 23-50 is a set of photographs showing the sequential steps of using an embodiment of the invention according to the description in the section below called “Detailed Use of A Preferred Tool”.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to the Figures, there are depicted several, but not all, preferred embodiments of the present invention.
FIG. 1 depicts a side, perspective view of one embodiment 10 of the present Viking Knit hand tool in a hexagonal rod 12 . Rod 12 has an anchor hole 14 drilled into it near its top. Rod 12 has a six (6)-loop head 16 inserted into its top end, and a conical tip 18 secured to its bottom end. Tip 18 has hole 20 drilled through it generally perpendicular to the axis of rod 12 .
FIG. 2 depicts an exploded view of the hand tool 10 depicted in FIG. 1 . From FIG. 2 it is clear that loop head 16 has six (6) radially extending circumferential loops 22 and a central shaft 24 which fits into central axial hole 26 at the top of rod 12 .
FIG. 3 depicts a detail view of the six (6)-loop head 16 depicted at the top of FIG. 2 .
FIG. 4 depicts a side view of the hand tool 10 depicted in FIG. 1 .
FIG. 5 depicts a cross-sectional view of the hand tool 10 depicted in FIG. 4 . From FIG. 5 it is clear that central axial hole 26 extends from the top of rod 12 parallel to the axis of the rod down into anchor hole 14 , which anchor hole is drilled diagonally transversely through rod 12 .
FIG. 6 depicts a side, perspective view of the hand tool 10 depicted in FIG. 1 , but with an additional first row of wire loops 28 hanging from the loop head 16 .
FIG. 7 depicts a detail view of the first row of wire loops 28 depicted in FIG. 6 .
FIG. 8 depicts a side, perspective view of the hand tool 10 depicted in FIG. 6 , but with an additional second row stitch 30 of Viking Knit hanging from the first row of wire loops 28 .
FIG. 9 depicts a detail view of the first row of wire loops 28 and additional second row stitch 30 of Viking Knit depicted in FIG. 8 .
FIG. 10 depicts a side, perspective view of the hand tool 10 depicted in FIG. 8 , but with an additional third through twelfth rows of stitches 32 of Viking Knit hanging from the first row of wire loops 28 and second row stitch of Viking Knit 30 . From FIG. 10 , it is clear that the outer surface of the rod shapes the inside size and shape of the Viking Knit.
FIG. 11 depicts a perspective, detail view of the loop head 16 , removed from the top of the rod as the weave is created and extended upwardly, first row of wire loops 28 and twelve rows of stitches 30 and 32 of Viking Knit depicted in FIG. 10 . FIG. 11 also shows the inner diameter of the tube (IDT) made by the surface of the rod.
FIG. 12 depicts a perspective, detail view of the twelve rows of stitches 30 and 32 of Viking Knit depicted in FIG. 11 , with the loop head removed from the weave by clipping the first row of wire loops. FIG. 12 also shows the inner diameter (IDT) of the woven wire tube.
FIG. 13 depicts a side, perspective view of another, alternative embodiment 110 of the present Viking Knit hand tool in a dodecagonal rod 112 . Rod 112 has an anchor hole 114 drilled into it near its top. Rod 112 has a twelve (12)-loop head 116 inserted into its top end, and a conical tip 118 formed at its bottom end. Tip 118 has hole 120 drilled through it generally perpendicular to the axis of rod 112 . Recess 115 in the outer surface of the rod indicates for the length of the first row of the wire loops, and allows for additional room for the wire to slide under earlier stitches of wire and continuance of the weaving.
FIG. 14 depicts an exploded view of the hand tool 110 depicted in FIG. 13 . From FIG. 14 it is clear that loop head 16 has twelve (12) radially extending circumferential loops 122 and a central shaft 124 which fits into the top of rod 112 .
FIG. 15 depicts a side, perspective, detail view of the twelve (12)-loop head 116 depicted at the top in FIG. 14 .
FIG. 16 depicts a top view of another, alternative embodiment 210 of the present Viking Knit hand tool in a dodecagonal cone 212 . Cone 212 has a series of anchor holes 214 on two sides, and an opening 226 in its top end.
FIG. 17 depicts a side, perspective view of hand tool 210 , with a six (6)-loop head 216 in the small end of the cone, and with a twenty-four (24)-loop head 217 in the large end of the cone. Head 216 has six (6) radially extending circumferential loops 222 . Head 217 has twenty-four (24) radially extending circumferential loops 223 .
FIG. 18 depicts an exploded view of the hand tool 210 depicted in FIG. 17 . From FIG. 18 it is clear that head 216 with loops 222 has central shaft 224 which fits into hole 226 in the top of cone 212 . Also from this FIG. 18 it is clear that head 217 with loops 223 has a plurality of interior legs 225 which collectively fit into a hole in the bottom of cone 212 .
FIG. 19 depicts a bottom, perspective, detail view of the twenty-four (24)-loop head 217 depicted at the bottom of FIG. 18 . Head 217 has twenty-four (24) radially extending circumferential loops 223 , and several upwardly extending, spaced-apart legs 225 for fitting into the bottom of cone 212 .
FIG. 20 depicts a top, perspective detail view of the twenty-four (24)-loop head 217 depicted at the bottom of FIG. 18 . From FIG. 20 it is clear that head 217 has six (6) spaced-apart legs 225 .
FIG. 21 depicts a top view of another, alternative embodiment 310 of the present Viking Knit hand tool in a twenty-four (24)-sided cone 312 . Cone 312 has a series of anchor holes 314 on two sides, and an opening 326 in its top end.
FIG. 22 depicts a side, perspective view of hand tool 310 , with a six (6)-loop head 316 in the small end of the cone, and with a twenty-four (24)-loop head 317 in the large end of the cone. Head 316 has six (6) radially extending circumferential loops 322 . Head 317 has twenty-four (24) radially extending circumferential loops 223 .
Detailed Use of a Preferred Tool:
Referring specifically to FIGS. 23-50 , there are shown illustrations of the preferred methods of using the tool, which may be understood by reference to the following steps:
With a black permanent marker, draw a line around the hex rod approximately ¼″ from the top of the rod or apply the pin striping tape at the same height. Insert the loop head central shaft into the top hole. See FIG. 23 .
Cut 30″ of #26 gauge wire. Holding the rod in your left hand, insert one end of the wire into the top of the diagonal anchor hole, extending about 1 inch. Press the “anchor wire” down with your left forefinger to hold in place. See FIGS. 24 and 25 .
Row 1: Insert the remaining wire down through one of the head loops above the anchor hole. See FIG. 26 . Gently pull the wire down then cross over the top of the previous wire to form an elongated loop. See FIG. 27 . Use the black line as a guide to establish the length of the loop.
Use your left thumb to help hold the first loop in place. See FIG. 28 . Bring the wire down through the next head loop on the right. Pull the wire down, taking care not to distort the first loop. Keep the wire on top and cross to the right. See FIG. 29 .
Make 6 loops around. Keep the stitches similar in size and as evenly spaced as possible. Use the shape of the rod as a guide placing one loop on each side of the hex. This way, the outer surface of the rod determines the size and shape of the inside of the Viking Knit tube. The flat sides also allow extra space to get under the wire. Use the pin tool to help with spacing and to lift the wire if necessary. See FIG. 30 .
The pin tool is sharp. Keep the plastic cover on the point when not in use. Keep away from animals and small children. See FIG. 31 .
Row 2: Bring the wire, right to left, behind the first loop (on row one) at the bottom where the wires cross. See FIG. 32 . Pull through then swing the wire back to the right to form a small loop. See FIG. 33 . Working to the right, repeat on each loop around. See FIGS. 34 and 35 .
Row 3: Continue another round of loops. Use the first 3-6 rows (or more if necessary) to develop a consistent pattern.
The first few rows of Viking Knit can be cut away later, so don't worry if they aren't perfect. You will be amazed how much the draw plate helps to reposition and even out the stitches.
Row 4: Pull the beginning anchor wire out of the diagonal hole and cut close to work. Continue working around with the main wire.
As you continue to work, check to make sure you still have 6 loops on the rod.
Row 5 and beyond: continue working loops around.
Periodically slide the knit out the top of the rod every few rows, otherwise it may be hard to remove later. If it becomes stuck twist the knit tube around the rod to loosen.
Adding wire: move the last loop formed so that it is over the diagonal anchor hole at the top of the rod. See FIG. 36 .
Cut another length of #26 wire, 24-30 inches, or whatever length you are most comfortable working with.
Insert one end of the wire through the last wire loop and into the diagonal hole, extending about 1 inch. See FIG. 37 . Press the “anchor wire” down end with your forefinger to hold in place. Bring the free end of the wire under the next loop and continue. See FIG. 38 . Work 3-4 rows then cut all wires except the main wire to continue working.
Determining length: The final length of your knit depends on how many loops you start with, how far down you draw the knit and the size wire you use.
As a general rule, if you start with 6 loops #26 gauge and make a 6-inch length of Viking Knit, you can gain 2-3 inches or more depending on how small you reduce the tube. The smaller the hole draw the longer the knit. The number of feet needed varies but about 15 feet of wire should be enough for a bracelet.
Preparing the knit: Remove the completed length of Viking Knit from the hex rod. See FIG. 39 . Clip the top loops to remove the loop head and remove any loose wires. See FIG. 40 .
Roll the knit between the soft side of the fabric cloth several times. This helps align the stitching and makes drawing easier. See FIG. 41 .
Cut 3 pieces of #26 wire about 12 inches each. Insert the wires in through loops on rows 2 or 3. See FIG. 42 . Fold wires together and twist. See FIG. 43 . This will give you something to hold onto as you draw the knit through the draw plate. They will be removed later.
Draw plate: pull the knit through the largest hole several times. See FIG. 44 . Continue to pull through each hole several times until the desired length and width is achieved.
You can cut the Viking Knit to any length—it will not unravel. Clip any sharp ends (where added wires began and ended) that may protrude.
About wire: many colored wires have a copper base with color coating on top. They are generally quite durable, however you can scratch the surface color off if not careful.
Different gauges of wire change the length and width of the knit: #24 and #28 gauge wires are suitable. #20 gauge is usually too hard to work.
To make a smaller diameter knit experiment by starting with 4 loops and #26 gauge or 5 loops with #28 gauge. This will allow you to pull the knit through the smallest hole on the draw plate. Just skip one or two loops on the loop head and space accordingly around the rod.
Making Coiled Wire End Caps
Use the Viking Knit hand tool described above to make two 3-4 inch lengths of coil.
Cut a 12″ length of #20 gauge wire and insert one end into the small hole at the cone end of the hex rod. See FIG. 45 .
Holding the rod with your right hand and the long wire in your left, turn the rod to wind the wire 3-4 times around the cone. See FIG. 46 . Add the coil and continue to wind. See FIGS. 47 and 48 .
Cut the wire ½-inch at the bottom and make a small loop. See FIG. 49 . Cut the top wire to release the coil. See FIG. 50 . Finish by adding a loop at the top. The technique for making a Viking Knit with the cone tool is essentially the same as described above.
Advantages:
The Viking Knit Hand Tool eliminates the need for repeatedly creating a new start-up bundle for each project and instead uses a fitted, removable, free-turning, interchangeable loop head inserted into the top center of the rod according to the invention.
The hard plastic nylon rod material is more durable than a dowel or pencil. The vertical shape is preferable over a bent Allen wrench. Constant removal of the Viking Knit wire weave can wear down other, softer materials. The lightweight material is portable and does not necessitate the use of a stationary stand, such as a vise or clamp.
A diagonally drilled anchor hole makes startup, and the addition of new wire, easier by creating tension and a stationary direction for the new wire to be attached. In use, the last stitch of the Viking Knit is aligned over the top diagonal hole on the rod. The new wire is inserted through the existing knit stitch and down through the diagonal hole extending about 1″. A forefinger is placed on the extended end to provide tension. The new wire is in position for the next stitch. After several rows of stitching the 1″ extended end and the original wire are cut away leaving the new wire.
A starting line, indent in the outer surface of the rod, or loop length guide, is provided at the top of the rod, just below the wire loop attachment. The line aids in positioning the first row of Viking Knit.
The hex shape, plastic nylon rod reduces the need for an awl or other pointed instrument to lift the wire from the rod because the flat surfaces allow more clearance room for getting under the initial wire and adding new stitches. Lessening the use of an awl or other pointed instrument to move the wire also reduce the changes of accidentally scratching the surface of the wire, especially in the case of copper-based, color coated wires.
The six sides of the rod also compliment the 6-loop metal head insert. This collaboration is helpful in initially with forming and positioning the first rows of Viking Knit stitches. The rod is constructed of Quadrant Nylon Hexagon Bar, ¼″ across flats (USP item #47521), measuring approximately 6 inches in length (vertical).
A vertical 1/16-inch hole, drilled in the top of the rod approximately ½″ in depth is referred to as the central axial hole.
A ⅛-inch adhesive tape strip may be applied around the circumference of the rod approximately ¼′inch from the top of the rod, referred to as the “loop length guide”. Alternatively, a black line can be drawn with a permanent marker.
In one embodiment, the “wire loop attachment” is comprised of one ⅛″×⅜″ aluminum blind rivet and one 6-loop Bali silver bead cap, #C2010 0.45 grams, 4×10 mm made in Indonesia (beads-park.com). The bead cap is permanently adhered to the top of the rivet. The rivet and bead cap are then inserted into the central axial hole at the top of the rod.
A second 1/16-inch hole, drilled at a slight diagonal, starting approximately 1-inch from the top of the rod, allows the addition of start up or new wire. It is referred to as the “anchor hole”.
A cone wire cap tool is permanently attached at the bottom of the rod. The cast metal cone is approximately ⅞-inch in length, part #BM60606-PE-003. A 1/16-inch hole is drilled through the metal cone near the smallest point. The hole is used to insert a base wire. Coiled wire, beads or other materials are added to the base wire. The base wire is then wrapped about the coil shape to form an end cap. Alternately, the hex rod itself may be shaped or sharpened at the bottom end to form a cone shape, eliminating the need for a metal cone. The cone wire cap tool is not essential to the creation of the Viking Knit weave; it offers a complimentary alternative finishing technique. However, the cone wire cap is also convenient for another important function associated with the Viking Knit Hand Tool. If the woven tube of wire becomes excessively tight on the rod or cone, the tube may be taken off, the rod or cone turned over and passed through the inside of the tube like a reamer. This way, due to the increased diameter of, for example, tip 18 ( FIG. 1 ), or tip 118 ( FIG. 14 ), the inner diameter of the woven tube will be increased, without the danger of scratching the wire, and the woven tube may be conveniently reinstalled on the rod or cone for additional weaving with a more relaxed fit.
One advantage of the Viking Knit Cone Tool is that, instead of limiting the traditional Viking Knit woven wire construction to a single, cylindrical shape, the cone form allows the woven knit to be formed into additional sizes and shapes, like open or closed cones, that add new dimension and opportunities for its use. The cone also eliminates the need to repeatedly create a new start-up bundle for each project and instead uses two or more fitted, removable, free-turning, interchangeable metal or plastic loop heads that can be inserted at either end of the cone. Heads can have a varying number of loops. The shape of the woven tube around the cone allows design options not available on the traditional straight rods.
The hollow cone has six flat sides at the smaller end (¼″) converting to 12 or 24 flat sides at the larger end (1¼″). The overall length is 5″. The six sides of the cone compliment a 6-loop plastic or metal head insert. A 12- or 24-loop metal or plastic head is used at the larger end. The flat surfaces are useful initially in and positioning the first rows of Viking Knit stitches: one or two stitches on each flat surface are useful for measuring stitch length, girth and shape.
The hollow cone is constructed of a plastic carbon and/or nylon reinforced material. Horizontal anchor hole sites of about 5/64 inch diameter are aligned at about ½ intervals down the length of the cone on one or both sides. The small end of the tool is a ¼″ hexagon shape, graduating to 1¼″ with 12 or 24 sides at the large end. Six-loop and a 24-loop head attachments are inserts at either ends of the cone.
Alternatives:
The hex tool may be modified in a number of respects, all without departing from the original intent and concept.
The diameter, length and hex shape could be changed to a larger or smaller diameter and the number of flat-sided surfaces could also be changed, for example, a ⅜″ rod with four sides or a ½″ rod with eight sides.
The rod material could be changed to wood, metal or other plastic materials. It can be solid or hollow. The rod may be round in diameter and not have flat sides at all. It could be attached to a stationary surface if necessary by means of a stand, vise or clamp.
The wire loop attachment can be shaped of a one-piece solid metal or plastic material with an increased or decreased number of loops forming the head. The size, depth and diameter of the rivet or pin inserted into the rod may vary in size.
Also, interchangeable wire loop attachments, of varying loop length and varying loop holes, could be used alternately with the same rod size or different rod sizes, depending on the style of Viking Knit mesh desired. Thus one could mix-and-match a five loop wire loop attachment with a five-sided ½″ rod or a five-sided ¼″ rod.
The number of wire loops on the wire loop attachment head need not correspond to the same number of flat sides on the rod. The flat sides of the rod help make the Viking Knit wrapping technique easier but can also aide in the placement of the Viking Knit loops.
The metal cone wire wrap accessory could be manufactured as part of the actual rod by sharpening the end of the rod into a graduated cone shape with an insert hole drilled at the end.
An alternative method for making the permanent or semi-permanent starting line at the top of the rod could be fashioned by the use of painted, a routed crevice or by burning or engraving a line onto the material.
The diagonal anchor hole could be located at varying heights and vary in diameter. Additional anchor holes could be added as starting points or to accommodate more than one wire.
The diameter of the rod, the number of starting loops, the size of wire used and the draw plate holes all contribute to determining various textures, diameters and sizes of a completed Viking Knit weave project.
The cone material could be changed to wood, metal or other plastic materials. It can be solid or hollow. The cone may be totally round in diameter and not have flat sides at all. It could be attached to a stationary surface if necessary by means of a stand, vise or clamp.
The plastic or metal loop attachments can be shaped of a one-piece solid metal or plastic material with an increased or decreased number of loops forming the head.
Interchangeable wire or plastic loop attachments, of varying loop lengths and varying loop holes, could be used alternately with the same cone size or different cone sizes, depending on the style of Viking Knit mesh desired.
The number of wire loops on the wire loop attachment head need not correspond to the same number of flat sides on the cone. The flat sides of the cone help make the Viking Knit wrapping technique easier but can also be used as a teaching aide to indicate the correct placement of the Viking Knit stitches.
Horizontal or vertical anchor holes could be located at varying heights and vary in diameter. Additional anchor holes could be added as starting points or to accommodate more than one wire.
The diameters of the cone, the number of starting loops at either end, the size of wire used and the draw plate holes all contribute to determining various textures, diameters and sizes of a completed Viking Knit weave project.
The end of the cone can be altered to include an end cap tool can be with the addition of an about 5/64 inch hole drilled through the cone about ¼″ from the end. The hole is used to insert wire and wrap about the cone shape formed an end cap that may be used to complete a Viking Knit project.
Variations of this invention will occur to those skilled in the art. All such variations are intended to be within the scope and spirit of the Viking Knit Hand Tool, and not limited to those alternatives listed. A feature disclosed herein may be used together or in combination with any other feature on any embodiment of the tool. It is also contemplated that any feature may be specifically excluded from any embodiment of this tool.
Although this invention has been described above with reference to particular means, materials and embodiments, it is to be understood that the invention is not limited to these disclosed particulars, but extends instead to all equivalents within the scope of the following claims. | This invention in one embodiment comprises a cylindrical rod with a rotating, removable loop head inserted into the center of the top end of the rod. The loop head is inserted into a vertical hole drilled into the top end of the rod, wherein the loop head is able to rotate in the hole. The loop head has a plurality of outwardly radially extending circumferential loops that receive wire for bending and weaving into the Viking Knit. Preferably, the rod also has an anchor hole, drilled diagonally through the rod near its top end, for receiving and securing a wire. Preferably, the rod also has a conical wire wrap attachment at the bottom of the rod for making wired end caps to cover or enclose the finished Viking Knit Weave. In another embodiment, this invention comprises a hollow cone with a rotating, removable loop head inserted in either or both ends of the cone. | 3 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority from U.S. Provisional Patent Application No. 61/193,375 filed Nov. 21, 2008, the contents of which are being incorporated herein by reference.
FIELD OF THE INVENTION
[0002] The present invention relates to a connector for use in building construction to permit relative movement between two components.
SUMMARY OF THE INVENTION
[0003] It is well known to use connectors to join components used in a building. These connectors may be as simple as plates extending across the joint between a pair of components or may be more complex so as to permit alignment and adjustment between the components. One area in which connectors are used is in the connection between a post and beam. Typically, such a connector will consist of a plate secured to the beam with a threaded rod extending from the plate into a bore in the end of the post. A nut on the threaded rod bears against the end face of the post and rotation of the nut can adjust the relative spacing between the end of the post and the beam. This is particularly useful to ensure that the post is properly supporting the beam in a horizontal manner and also to allow subsequent adjustment to accommodate building movement.
[0004] Movement of the building arises typically through the shrinkage of the wood used in the construction. Relatively small changes in the dimensional lumber can accumulate to represent a relatively large change in overall dimensions and, if this is not accommodated, the beam may not be properly supported or may not remain horizontal. This is particularly acute in log home construction using logs as the basic wall material as the logs are machined and assembled in a green state. Subsequent drying of the logs produces a significant change in the overall vertical height of the wall.
[0005] Many buildings also incorporate a porch or similar overhanging structure in which the roof structure projects beyond the walls and has its outer ends supported on a post. The roof structure is designed on the assumption that there are multiple points of support, that is the walls and the posts, and to maintain the integrity of the roof, it is therefore necessary to ensure that the top of the post and the walls remain aligned. Shrinkage of the wall, particularly where a log wall is used, can therefore impose significant bending loads on the roof that, in extreme cases, may result in failure of the roof.
[0006] Normally, the connection between the post and the roof structure is provided by a connector of the type described above so that the spacing between the end of the post and the roof can be adjusted as the building dries. This arrangement is satisfactory for normal static loads but does not take into account dynamic loads that may be imposed on the roof, such as by wind loads. In extreme weather conditions, the loads imposed on the roof, particularly on an overhanging roof, can create a net uplift on the roof structure. In this condition, the connection between the post and beam cannot provide any assistance to resist the uplift. The entire load is placed on the connection between the walls and the roof structure and failure of this connection can result in damage to the roof or loss of the roof in extreme circumstances.
[0007] Attempts have been made to provide a connector that will resist vertical loads in both directions while still accommodating limited vertical adjustment. One such device is that sold by Simpson Strongtie under model identification PPRC in which the threaded rod is received in a flange that is itself secured to a plate. The flange however has to be manufactured so as to allow rotation relative to the post to accommodate height adjustment but at the same time be retained by the plate. As such, there is significant overlap between the flange and the plate so that a very high torque is required when adjustments are to be made. These devices are suitable for relatively light loads only.
[0008] It is therefore an object to the present invention to provide a connector that permits adjustment between a pair of components whilst providing resistance to loads in opposite directions.
[0009] In general terms, the present invention provides a connector having a pair of members, one of which is to be secured to one component and the other of which is to be secured to the other component. An adjustable abutment acts between the two members to inhibit movement in one direction. A ratchet mechanism is also positioned between the two members that allows rotation in the one direction but inhibits it in the opposition direction.
[0010] Preferably, the ratchet mechanism includes a collet that engages the outer surface of a threaded rod and forms one of the members. The collet abuts an inclined face so that relative movement of the threaded rod in one direction causes the collet to engage the threaded rod and inhibit such movement. Preferably, also, the adjustment is a nut on the threaded rod that controls the relative disposition between the two members.
[0011] The connector may be used to connect a post and a beam structure and may be used at either end of the post. The post may be located within the building, such as to secure an upper floor or may be located outside the building, such as to support an overhanging porch.
[0012] Preferably the collet is spring biased into engagement with the threaded rod.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] Embodiments of the invention will now be described by way of example only with references to the accompanying drawings in which
[0014] FIG. 1 is schematic representation of a building.
[0015] FIG. 2 is a enlarged view of a portion of the building shown in FIG. 1 .
[0016] FIG. 3 is an enlarged view of FIG. 2 .
[0017] FIG. 4 is a view similar to FIG. 2 of an alternative configuration.
DETAILED DESCRIPTION OF THE INVENTION
[0018] Referring therefore to FIG. 1 , a building, generally indicated 10 , has walls 12 constructed from logs 14 that support a roof structure 16 . The roof structure 16 has trusses 18 that include a lower chord 20 supported on a top plate 22 interposed between the uppermost log 14 and the chord 20 .
[0019] The chord 20 extends beyond the wall 12 to provide a roof structure for a porch and is supported by posts 24 . The posts 24 extend from a foundation 26 to a beam 28 that extends the length of the roof 16 . It will be appreciated that the number of posts will generally be less than the number of trusses 18 and that the beam 28 therefore spans several trusses 18 between the posts 24 .
[0020] A connector 30 is located on each of the posts 24 , either at the upper end adjacent to the beam 28 , as shown at post 24 a in FIG. 1 , or alternatively at the lower end of the post, as shown at post 24 b , in FIG. 1 . Each connector is similar and simply inverted according to its disposition. For ease of reference, the connector 30 associated with the post 24 a will initially be described with reference to FIGS. 2 and 3 .
[0021] Referring therefore to FIGS. 2 and 3 , the connector 30 includes a first member 31 with a plate 32 having holes 34 to receive fasteners 36 . Typically, the plate 32 is square and a hole 34 is located adjacent to each corner. A threaded rod 38 is welded to the plate 32 to project to one side of the plate. The threaded rod 38 can be either a fine or a coarse threaded rod and carries a nut 40 that acts as an adjustable abutment. A washer 42 has a central hole 44 through which the rod 38 can pass freely. The position of the washer 42 on the rod 38 is therefore controlled by the nut 40 which can be rotated on the threaded rod 38 to adjust the axial position of the nut 40 relative to the plate 32 .
[0022] The rod 38 is received in a central bore 46 of a barrel 48 that forms a secured member 49 . The barrel 48 has an external thread 50 at one end which is received in a threaded counter bore 52 of an end plate 54 . The end plate 54 has a central hole 56 through which the rod 38 can pass freely and has holes 58 to receive fasteners 60 .
[0023] The barrel 48 is counterbored to provide a internal chamber 62 continuing from the bore 56 and receiving the threaded rod 38 . End wall 64 of the chamber 62 is conical to provide end surfaces of the chamber 62 that are inclined to the axis of the bore 46 .
[0024] A ratchet mechanism is located in the chamber 62 and includes a collet 66 with a pair of jaws 68 having inner part cylindrical faces 70 that are complimentary to the outer surface of the rod 38 . The jaws 68 each have inclined leading edges 72 at one end that are complimentary to the inclined face 64 of the chamber 62 . The opposite end of the jaws 68 is a radial face 74 to bear against a retainer washer 76 . The washer 76 is freely slidable on the threaded rod 38 and is biased into engagement with the jaws 68 by a spring 78 . The spring 78 acts between the retainer washer 76 and the plate 54 and is retained captive within the chamber 72 .
[0025] To install the connector 30 , a bore 80 is drilled in the end face 82 of the post 24 a . The bore 80 provides a clearance for the threaded rod 38 and extends a sufficient distance into the post 24 a to accommodate the rod 38 over the extent of travel anticipated. The connector 30 is assembled so that barrel 48 is threaded on to the end plate 54 with the collet 66 , spring 78 and retainer washer 76 assembled within the chamber 62 and the end plate 54 then secured to the end face 82 of the post 24 a with the fasteners 60 . The rod 38 may then be inserted into the central bore 46 with the rod 38 engaging the jaws 68 to move them away from the inclined surface 64 and increase that spacing to allow the threaded rod 38 to pass between the jaws 66 . The movement is accommodated by the spring 78 . With the rod 38 inserted, the post 24 a may be positioned relative to the beam 28 .
[0026] Once the post 24 a is positioned vertically, the nominal length of the connector 30 can be adjusted by rotating the rod 38 so that it is threaded out of the jaws 68 . Preferably the inner surfaces 70 are formed with a complimentary thread so that rotation of the rod 38 will cause axial adjustment relative to the barrel. During this assembly, the nut 40 is positioned adjacent to the plate 32 so as not to interfere with installation of the post 24 a in the desired position.
[0027] With the plate 32 secured against the beam 28 , the fasteners 36 are inserted and the nut 40 threaded down the rod 38 to bring the washer 42 into abutment with the barrel 48 . In this position, the post 24 a securely supports the beam 28 and relative vertical movement of the beam 28 toward the post 24 a is inhibited by the nut 40 on the rod 38 . At the same time, the jaws 68 are thus held in engagement with the inclined surface 64 so that the jaws 68 engage the surface of the rod 38 by virtue of the spring 78 . The opposite end of the post 24 a is secured to the foundation 26 by a conventional fixed fastener to prevent vertical movement.
[0028] In the event that an upward vertical load is applied to the beam, for example due to wind loading, the rod 38 will attempt to move vertically out of the barrel 48 . The jaws 68 are carried with the rod 38 and by virtue of the inclined surfaces 64 are forced into engagement with the rod 38 to inhibit any relative movement between the rod 38 and the barrel 48 . A secure connection between the beam 28 and the post 24 a is thus provided.
[0029] When it is necessary to reduce the relative vertical spacing between the beam 28 and the post 24 a due to shrinkage of the walls 12 , the nut 40 is rotated to move it along the threaded rod 38 toward the beam 28 . The rotation permits the rod 38 to move relative to the barrel 48 into the bore 80 and carries the jaws 68 away from the inclined surface 64 . The jaws 68 spread within the chamber 62 allowing the threaded rod 38 to pass between the jaws 68 in an axial direction. The nut 40 therefore governs the relative spacing between the beam 28 and the post 24 a and may be used to ensure that the lower chord 20 of the truss 18 is properly supported on the wall 14 and the post 24 . Any upward vertical movement caused by reversed loading of the roof will again cause the jaws 68 to engage the rod 38 and inhibit such movement.
[0030] It will be seen therefore that by providing the ratchet connection between the rod 38 and the post 24 by the spring loaded collet, so that relative movement is permitted in one direction but inhibited in the opposite, vertical adjustment between the beam and the post can readily be accommodated but at the same time, relative movement in the opposite direction is inhibited.
[0031] As indicated in FIGS. 1 and 4 , the connector 30 may similarly be used at the opposite end of the post such that the plate 54 is secured to the lower end face of the post 24 b and the opposite end face of the post 24 b connected directly to the beam 28 . In this arrangement, the plate 32 is secured to the foundation 26 and adjustment between the post 24 b and the beam 28 accomplished as described above. Again, the connector 30 is effective to resist reverse loading on the roof whilst permitting proper adjustment to maintain alignment between the beam 28 and the walls 14 .
[0032] The connector 30 has been described above in the context of securing an external over hanging roof structure. It will of course be apparent that similar connections can be used within the structure of a building to connect a supporting beam to a foundation or other structure and accommodate vertical loading. The connector 30 is able to resist the reversed loadings induced by high winds passing over the roof while still maintaining the functionality to permit adjustment of the relative alignment between the different building components. The connector may therefore be used in a basement to support a beam in the main floor of the building, or could be used in an upper floor within a wall structure to connect a roof structure to an internal support beam. | A connector to connect a pair of components of a building and transfer a load from one to the other. The connector comprising a pair of members, each to be connected to a respective one of the components, and an adjustable abutment acting between the members to inhibit relative movement between the members in one direction. The ratchet mechanism acting between the members to permit movement in the one direction and to inhibit relative movement in an opposite direction, whereby adjustment of the abutment to cause relative movements in the one direction is accommodated by the ratchet mechanism. | 4 |
BACKGROUND OF THE INVENTION
This invention relates to electric motor driven fluid handling assemblies and, more particularly, to a seal-less pump and motor assembly having improved electrical characteristics.
There are various applications in which a mechanical apparatus may be exposed or immersed in a fluid and adapted for being driven by an electric motor. Typical examples are a water pump in a dishwasher or clothes washing machine and an agitator in a clothes washing machine. In such applications, it is desirable to isolate the electric motor from the water both to protect the motor and to prevent electric shock hazards. A classic method of isolating the electric motor is to extend a shaft from the mechanical apparatus through a seal to the motor. The shaft to seal interface must provide for relative shaft motion and therefore is subject to wear and deterioration leading to fluid leaks at the interface.
An alternative strategy which avoids the potential seal leakage is to place the motor into the fluid environment. However, this strategy is inadvisable for water pumps and can be expensive when the electrical connections of the motor must be fluid proof.
Another method which avoids the seal leakage problem is to construct the apparatus, e.g., a pump, within a housing which also encompasses the motor rotor. The housing closely envelopes the circumference of the rotor without contact. The motor stator is then positioned outside the housing about the rotor. With a typical plastic housing, this arrangement requires a relatively large space between the rotor and stator, i.e., the effective "air gap" may be as much as 10 times the normal motor gap for an induction motor. For example, a minimum thickness for a plastic housing is generally about 0.09 inches while a nominal air gap for an efficient induction motor is about 0.01 inch. The resulting construction produces a motor which is oversized, expensive and inefficient with poor operating characteristics.
Still another prior art attempt to resolve the electric motor/pump problem of isolating the motor from the pumped fluid is to use a permanent magnet motor. Such a motor is expensive due to both the magnet cost and fabrication costs to meet water resistant constraints. Further, simple single phase permanent magnet synchronous motors are sometimes used for this purpose and are difficult to start in a controlled direction and have synchronization problems. If an electronically commutated control is used, the motor and drive cost increases dramatically.
Another challenge when designing a seal-less pump is that, even in relatively clean water, the wet rotor of a seal-less pump is subject to corrosion because of the presence of dissolved oxygen. A conventional technique for resisting corrosion is to coat the rotor with a material such as a plastic or an epoxy or to plate the rotor with a corrosion resistant metal such as aluminum. Crevices between rotor laminations and/or between rotor laminations and the rotor cage cause effective sealing to be difficult, and the coatings sometimes fail after a number of immersions.
To avoid the crevices, a solid iron rotor can be used. Sheet rotors comprising a copper shell brazed to a solid steel core are used in X-ray tube target rotators to withstand high temperatures, high speed, and vacuum conditions. Such rotors are typically coated with infra-red emitters.
Solid iron and steel cores can become corroded, and skin effects can affect electromagnetic steady state performance in the solid cores even at low slip frequencies. These skin effects can lead to difficulties in starting the rotor.
SUMMARY OF THE INVENTION
Among the several objects of the present invention may be noted the provision of an induction motor driven fluid handling apparatus which eliminates the necessity of a seal at any rotating interface; the provision of an induction motor driven fluid handling apparatus in which the motor rotor is encompassed by an apparatus housing while the motor air gap is maintained at a nominal value; the provision of an induction motor driven fluid handling apparatus which overcomes the size, inefficiency and poor operating characteristics of prior seal-less motors; the provision of a method for construction of an induction motor driven seal-less pump; and the provision of an economical method of making a corrosion resistant induction motor rotor that will have a good electromagnetic performance.
Briefly, in one embodiment a seal-less pump and electric motor assembly includes a motor rotor fixed to a driving shaft connected to an impeller in the pump assembly. The motor rotor and impeller are enclosed in a common housing such that the rotor rotates within any fluid being pumped by the impeller. The portion of the housing circumscribing the motor rotor includes a plurality of axially extending, circumferentially spaced strips of magnetic material penetrating through the insulative plastic material of the housing. Each of the strips coincide with corresponding ones of the pole teeth of a motor stator circumscribing the outer portion of the housing such that the strips in the housing act as extensions of the pole teeth.
In another embodiment, a rotor of a seal-less pump comprises a rotor shaft, a rotor core including a molded magnetic powder and plastic composite material surrounding the rotor shaft, and an annular corrosion resistant electrically conductive tube surrounding the rotor core.
BRIEF DESCRIPTION OF THE DRAWINGS
For a better understanding of the present invention, reference may be had to the following detailed description taken in conjunction with the accompanying drawings in which:
FIG. 1 is a simplified cross-sectional view of a prior art seal-less pump and electric motor assembly;
FIG. 2 is a simplified cross-sectional view of a seal-less pump/induction motor assembly incorporating the present invention;
FIG. 3 is a perspective view of a pump enclosure segment according to the present invention;
FIGS. 4 and 5 are enlarged sectional views of sections of the enclosure segment of FIG. 3 showing alternate forms of magnetic strips and pole teeth extensions.
FIGS. 6, 6A, 6B, 6C, 6D, and 6E illustrate still other cross-sectional shapes for the magnetic strips and pole teeth extensions;
FIGS. 7 and 8 illustrate manufacturing steps for producing the inventive housing segment;
FIG. 9 is a view of a conventional rotor lamination sheet;
FIG. 10 is a perspective view of a rotor embodiment of the present invention; and
FIGS. 11 and 12 are sectional side views of a fixture for fabricating the rotor of FIG. 10.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 is a simplified cross-sectional view of a prior art seal-less pump/induction motor assembly of the type with which the present invention may be used. The pump 10 comprises an impeller 12 positioned in an enclosure 14 forming a portion of a pump housing 16. Another enclosure 18 forms another portion of housing 16 and encompasses a rotor 20 of an alternating current (AC) induction motor 22. The housing 16 is circular about an axis 24 through the motor rotor 20 and impeller 12. A shaft 26 of rotor 20 lies on axis 24 and connects to impeller 12 so that rotation of rotor 20 drives impeller 12. An O-ring 28 positioned in an annular groove 30 in a wall 32 of enclosure 14 provides a watertight seal between enclosure 14 and enclosure 18. Enclosure 18 may be attached to enclosure 14 by threaded fasteners, clamps or other means well known in the art. For simplicity, neither the enclosure-to-enclosure attachment means nor the pump inlet and outlet lines are shown. Further, the bearing assemblies which support shaft 26 for rotation are omitted.
The motor 22 includes a stator 34 positioned outside enclosure 18 circumscribing rotor 20. Pole faces of stator 34 are desirably abutting the outer surface of enclosure 18 in order to reduce the gap between the pole faces and the outer surface of rotor 20. However, the minimum thickness of enclosure 18 is limited to about 3/32 inch in order to provide sufficient strength and stiffness of the enclosure. For good performance and efficiency and reasonable size, the desired air gap, i.e., the spacing between the stator pole teeth faces and the rotor outer surface should be about 1/100 inch. Thus, the plastic enclosure 18 results in a stator-rotor gap which is about 10 times the desired gap and detrimentally affects motor size, performance and efficiency. Obviously, the stator 34 operates in open air while rotor 20 is submerged in whatever fluid, e.g., water, is being pumped.
Turning to FIG. 2, there is shown a cross-sectional view taken along the line 2--2 of FIG. 1, illustrating an improved electric motor driven pump assembly in accordance with the present invention. The elements of FIG. 1 remain unchanged, the invention lying in the construction of enclosure 18. Considering FIG. 2 in combination with FIG. 3, it will be seen that the inventive enclosure 18 is constructed with a plurality of circumferentially spaced ferromagnetic strips 36 integrally formed in the plastic material of enclosure 18, i.e., the strips 36 alternate with plastic elements 48. Each of the strips 36 has an inner face 38 coincident with the inner face 40 of enclosure 18 allowing the strips 36 to be closely positioned facing rotor 20, preferably within 1/100 inch. The strips 36 extend through enclosure 18 and are accessible from an outer surface of enclosure 18 allowing direct contact with respective pole teeth members 42 of stator 34. For simplicity, the windings 44 of FIG. 1 are not shown in the pole teeth interstices 46 of FIG. 2. It will be appreciated that various numbers of pole teeth may be used and that there may be multiple pole teeth in each magnetic pole of stator 34. The strips 36 are desirably formed with the same axial length and width as the pole teeth 42.
As shown in FIG. 3, at least a portion of the enclosure 18 may be formed as an annular sleeve comprising a plurality of molded magnetic tooth tips or strips 36 interspersed with conventional plastic strips 48 to form a segmented ring 50. In general, the strips 36 are formed by combining iron powder in a plastic matrix and then either extruding or molding the individual strips 36 from the plastic into a shape to match the width and length of a stator tooth with which the ring is to be used. Once the strips 36 have been formed, these strips can then be set into a die or mold that will be used to make the injection molded pump shell or enclosure 18 and molded in place with the remainder of the enclosure 18. The sizing of the segmented ring 50 is selected so that when the motor stator is slid over the enclosure 18, there is a tight fit between each of the strips 36 and a corresponding one of the pole tooth members 42. In effect, the strips 36 become extensions of the pole teeth 42. In this way, the magnetic gap is reduced to that of only the spacing between the outer surface of the rotor 20 and the inner surface of the enclosure 18. Such spacing may be only that gap required to provide a mechanical clearance between the enclosure 18 plus a few mils for stator fit mismatch. Thus, the motor 22 may be of conventional design and size except for a small extra tooth leakage flux and a slightly larger effective gap between the ends of the stator teeth and the outer surface of the rotor 20. It is expected that the powdered iron in the plastic or epoxy matrix will have a lower permeability and higher losses than a steel lamination, but since the volume of the powdered iron matrix is relatively small, the effect will not be of major significance in overall motor performance. A typical powdered iron material useful in forming the strips 36 of the present invention is available from the Hoeganaes Corporation in the form of an atomized iron powder, similar to that used in sintered powder metallurgy production, but with each particle of iron powder coated with a layer of ULTEM™ polyetherimide (ULTEM is a registered trademark of the General Electric Company).
Referring now to FIGS. 4 and 5, there is shown enlarged cross-sectional views of a portion of the enclosure 18 with two different forms of the strips 36. In both FIGS. 4 and 5, the enclosure 18 is molded with the strips 36 having a different radial thickness than the adjacent plastic sections between the strips. Accordingly, the enclosure 18 appears to have a plurality of grooves 52 overlying each of the strips 36. The grooves facilitate accurate matching of the stator to the magnetic strips by forcing the stator teeth into the grooves between the plastic elements and onto the ferromagnetic strips 36. During the assembly process, the grooves enable the stator to be guided into the proper position without any special tooling. For conventional motor stators having a broad or widened tooth tip 54, the arrangement shown in FIG. 4 may be preferred in which the broadened tooth tips simply mate with a wide strip 36. The strips 36 then merely create an extra thick tooth tip. This arrangement results in some additional leakage flux with a penalty in the pullout torque generated by the motor but still provides significant advantages over the prior art. An alternative is to fabricate the stator teeth with straight segments as shown in FIG. 5 and to form the strips 36 in a conventional tooth tip configuration. This arrangement improves the leakage flux problem and further improves pullout torque but does require a redesign of the stator laminations to produce the stator teeth without the conventional tooth tip 54.
It will also be noted in FIG. 4 that the strips 36 are formed with grooves 56 along opposite sides. These grooves 56 may be useful in providing a better binding of the strips 36 to the adjacent plastic sections 48 of the enclosure 18. FIG. 6 illustrates some additional shapes which may be useful in forming the strips 36. These additional shapes may be useful in providing improved sealing, simplifying manufacturing or merely to give greater strength to the outer shell of enclosure 18.
FIGS. 6A, 6B, 6C, 6D, and 6E illustrate other shapes of the pole teeth extensions and strips 36. The radial shape of a magnetic strip affects the flux pattern in the magnetic strip and can provide various physical features to enhance the fabrication process. The shape of a strip can be used to aid the flux transition from a high permeability steel to a lower permeability magnetic strip and to reduce volume occupied by a magnetic strip. Cost of a magnetic strip is proportional to density. It can be cost effective therefore to reduce the density of a magnetic strip while permitting an acceptable level of magnetic losses. The required magnetic strip density can be decreased by reducing the flux density and total flux passing through the magnetic strip.
FIG. 6A encourages alignment of the stator pole teeth members 42 with strips 36 by forming each strip 36 with a radially outward extending portion 36A. Pole teeth members 42, preferably formed of punched and stacked laminations, are designed with an end shaped with a depression to fit about and abut against strips 36. The height of the portion 36A above the outer surface of the rotor shell 48 is about 0.057 inches for a sleeve or shell 48 thickness of about 0.081 inches. This embodiment is useful for alignment but requires more magnetic strip material and promotes a higher flux density in the transition region.
FIG. 6B is a reversal of FIG. 6A in which the pole teeth members 42 are formed with a rounded protuberance 42A which fits into and engages a shaped depression 36B in strip 36. This embodiment aids alignment, reduces the amount of strip material required, and promotes a lower flux density in the transition region of the magnetic strip.
Two potential challenges to fabrication of the seal-less pump are interference of stator winding endturn bundles (not shown) with segmented ring 50 (and pump/rotor housing 18) and difficulty in holding the stator windings in the stator slots prior to assembly with the pump/rotor housing.
FIG. 6C is a view of a stator tooth having vestigial tips 37 which protrude into the stator slot to help hold in place any slot insulator and/or slot wedge. Depending upon the size of the vestigials, the vestigials can also be useful for holding the slot windings in position. Having depressions in strip 36 and protuberances in teeth member 42, as shown in FIGS. 6B-6E, provides an increase in the minimum diameters that the endturn bundles can occupy towards the bore.
FIGS. 6D and 6E illustrate alternative positions for the vestigial tips where the edges of the vestigial tips are not aligned with the magnetic strip. In FIG. 6D, vestigial tips 37a are wider than the magnetic strip edge, and in FIG. 6E, vestigial tips 37b are narrower than the magnetic strip edge.
FIGS. 7 and 8 illustrate other possible intermediate stages of fabrication of an enclosure 18 in accordance with the present invention. In FIG. 7, the magnetic portion of a segmented ring 58 is positioned on a mandrel 60. The segmented ring 58 comprises a plurality of powdered iron and plastic composite tooth tips or strips 36 which can be bonded together by plastic strips 48 molded in between as shown in FIG. 3. The segmented ring 58 is initially formed on the mandrel 60 in a compression molding operation as shown in FIG. 8. A small end ring 62 of material is left at one end to assure that the teeth 36 remain in proper alignment. The mandrel 60 is coated with a release compound and has an outer diameter which forms the inner diameter of the segmented ring 58, i.e., it has a diameter equal to the diameter of the motor rotor 20 plus a desired clearance gap, e.g., about 1/100 inch. The mandrel 60 is positioned into a die 64 which has a plurality of slots surrounding the mandrel with each of the slots having the desired length and configuration of a strip 36 to be molded. The powdered iron and plastic matrix, e.g., ULTEM™ polyetherimide, is poured into the die 64 to fill the space around the mandrel 60 and a ram 66 is then brought down into the die 64 to compression form the segmented ring. The die 64 is heated during compression to mold the powdered iron and plastic into a composite part.
After molding, the mandrel 60 with the molded tooth tips or strips 36 attached is then withdrawn from the die 64. The mandrel 60 and tooth tips 36 are then inserted in a second die (not shown). A molten plastic is then injected into the spaces between each of the preformed strips 36 while the strips are in the die so that the spaces between each of the strips is filled with the molten plastic. The temperature and pressure with which the plastic is injected is selected based upon normal production injection molding of parts. The injected plastic will bond with the plastic base of the magnetic strips 36 thus forming a watertight solid enclosure. Preferably, the plastic is filled with glass fiber such that the expansion coefficients of the tooth tips 36 and the intermediate filler are reasonably matched. After molding and removal from the die, the temporary end ring 62 which was used to hold the molded strips 36 together can be severed from the final segmented ring. The enclosure 18 is then completed by positioning the segmented ring 50 (See FIG. 3) into a conventional pump casing mold (not shown) which molds the final entire enclosure 18 in a conventional manner.
While the above described method of producing the segmented ring 50 is a preferred method, an alternate method may be to extrude the ring 50 as a composite ring with both the magnetic strips 36 and the intermediate plastic sections in a single operation. Since the plastic base used in both the strips and the bonding plastic are the same or compatible, they will merge and bond in the process. The tooth tips formed by the extrusion process will be less dense than those formed using the compression molding process and will result in somewhat poorer electromagnetic performance. However, since the tooth tips form a very small part of the total magnetic circuit, it is believed that there will be little difference in overall motor performance between extruded and compression molded tooth tips.
FIG. 9 is a view of a conventional rotor lamination sheet 110. Induction motor rotors for small machines are conventionally fabricated by punching thin steel sheets (having thickness ranging from about 0.018 inches to about 0.030 inches) and stacking the sheets to form the rotor core. The holes near the periphery of the rotor core are generally filled with molten aluminum to form the rotor windings. Rings of aluminum are molded onto the ends of the windings to connect the windings together and form a "squirrel cage" winding. Stacking of rotor core sheets (laminations) permits the magnetic flux to fully penetrate the rotor during starting, aides in torque production, and can increase efficiency of the rotor during operation. Rotor stacks are often skewed to minimize slot interaction effects. As discussed in the background above, conventional induction motor rotors are conducive to corrosion when they become wet.
Starting and running performance of a corrosion resistant rotor can be achieved by pressing or shrink fitting an annulus of electrically conductive, corrosion resistant material over a solid steel rotor core. For solid steel rotor cores, there will be skin effects, especially during starting, and corrosion occurs.
FIG. 10 is a perspective view of a rotor embodiment of the present invention. A rotor core 112 comprises a molded magnetic powder/plastic composite material. In one embodiment, irregularly shaped iron particles individually coated with a plastic material such as ULTEM™ polyetherimide are compression molded with a shaft hole. Other examples of appropriate magnetic materials include steel, ferrite (iron oxide), stainless steel, nickel, and cobalt. Other examples of appropriate plastic materials include polymers and epoxies. The rotor fabrication process then is completed by applying a shaft 114 comprising a corrosion resistant material such as stainless steel and an annular tube 116 comprising a corrosion resistant electrically conductive material such as aluminum, brass, or copper. In another embodiment, the core is fabricated by extruding a long rod of material with a central hole and cutting off suitable lengths. This less expensive fabrication process results in some surface corrosion from metal exposed by cutting the end surfaces.
FIGS. 11 and 12 are sectional side views of one embodiment of a fixture 118 for fabricating the rotor of FIG. 10. First, hollow aluminum tube 116 is baked in air to form a hard aluminum oxide coating on all surfaces to resist corrosion. Tube 116 is positioned in a cylindrical die fixture 118. Shaft 114 is also positioned in the fixture. The fixture, tube, and shaft are then preheated to a predetermined molding temperature, and the coated iron particles 129 are preheated and poured into the fixture. It is useful to have a mold piece 120 adjacent tube 116 and fixture 118 to better guide particles 112a between the tube and the shaft and to prevent distortion of the tube 116. It is also useful to have a notch 124 in fixture 118 for supporting the rotor shaft.
The poured volume of particles should be greater than the finished rotor core size to allow for compression. A ram 122 can be brought down with a suitable force to compress the volume of particles, and raising the temperature will cause the particles to bond together and form a solid mass 112. After a cooling period, the finished rotor can be removed from the die. Whether preheating and/or cooling is necessary is dependent on the plastic material coating the iron particles.
The rotor of the present invention is expected to have good flux penetration and low losses in running. The molding process will leave a film of bonding material on the surface of the rotor which will provide an additional barrier to the individual particle coats, and a close bond between the core and the tube will prevent the entry of moisture into the core.
While the invention has been described in what is presently considered to be a preferred embodiment, many variations and modifications will become apparent to those skilled in the art. Accordingly, it is intended that the invention not be limited to the specific illustrative embodiment but be interpreted within the full spirit and scope of the appended claims. | A seal-less pump and electric motor assembly includes a motor rotor fixed to a driving shaft connected to an impeller in the pump assembly. The rotor and impeller are enclosed in a common housing such that the rotor rotates within any fluid being pumped by the impeller. The portion of the housing circumscribing the rotor includes a plurality of axially extending, circumferentially spaced strips of magnetic material penetrating through plastic material of the housing. Each of the strips coincide with corresponding ones of the pole teeth of a motor stator circumscribing the outer portion of the housing such that the strips in the housing act as extensions of the pole teeth. In one embodiment, the strips of magnetic material in the housing are formed by molding powdered iron in a plastic binder material. The strips are then placed in a mold in which the housing is formed by injecting plastic. The plastic binder in the strips melds with the injected plastic to form a continuous housing for enclosing the rotor. The ferromagnetic material strips extend through the housing and are spaced from the rotor surface by a normal air gap distance so as to improve the efficiency of the motor by having the magnetic strip act as extensions of the motor stator pole teeth. In one embodiment, the rotor includes a shaft, a core including a molded magnetic powder and plastic composite material surrounding the shaft, and an annular corrosion resistant electrically conductive tube surrounding the core. | 8 |
[0001] This application claims priority from previously filed U.S. provisional application 61/328,377 filed on Apr. 27, 2010 by Gerry Clarke under the title Prism Tripod.
FIELD OF THE INVENTION
[0002] The present device relates to surveying equipment in particular relates to a device and method for finding points and also for marking points namely a prism tripod and method of use therefore.
SUMMARY OF THE INVENTION
[0003] Modern day surveying methods use a robotic total station system in order to determine the location of existing points and also to demark the location of new points to be laid out and marked in the field.
[0004] Presently a prism is generally attached to a handheld post and/or pole, which generally has a pointed end for placement onto the desired location. A robotic total station surveying equipment will generally communicate via the prism to indicate to the user the location of the prism attached to a handheld post or a pole.
[0005] To a certain extent the steadiness of the hand in holding the post or pole on which the prism is mounted can determine the accuracy to which one is able to locate a given point. The users hand will never be totally steady and there will always be some motion and/or swaying of the post or pole on which the prism is located thereby creating a certain margin of error in the location of a specific point which the post or pole is touching.
[0006] In some instances the accuracy required by the engineering and/or architectural specifications is such that the surveyors find it difficult to obtain a quick and accurate location of particular points, which they need to lay out and determine the location of in the field.
[0007] In addition once that point or position is found using the handheld post or pole the surveyor then must in some manner mark or demark the location for future reference by construction personnel.
[0008] In practice often the surveyor will simply scribe or scratch the location of the point by forcibly scratching or scribing the end of the point of the post or pole into the ground, concrete, steel, or other material on which the post or pole is placed.
[0009] The combination of these factors creates a certain amount of uncertainty and error in locating and demarking points to be laid out by the surveyor and at times the accuracy that one is able to obtain using a handheld post or pole onto which a prism is mounted is insufficient in providing the accuracy required by the architectural or engineering specifications.
[0010] Therefore there is a need for a device and method for quickly and accurately locating points, which are already in existence or must be determined. There is a need for a device, which eliminates the variations introduced by the handheld post or pole which is currently used and also provides for a quick and accurate method of locating or demarking a point in the field.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] With the intention of providing demonstration of the characteristics of the device or method, an example is given below, without any restrictive character whatsoever, with reference to the corresponding figures, of a preferred embodiment of the device and method as follows;
[0012] FIG. 1 is a top schematic plan view of a geometrical layout of the elements of the base.
[0013] FIG. 2 is a top schematic plan view of the top surface of the base.
[0014] FIG. 3 is a side perspective schematic elevational view of the prism tripod shown together with a transponder mounted thereon.
[0015] FIG. 4 is a side perspective schematic view of the prism tripod without the transponder mounted thereon.
[0016] FIG. 5 is a side perspective schematic view of the prism tripod together with two prisms mounted on both the prism extension as well as the laser holder.
[0017] FIG. 6 is a schematic bottom plan view of the bottom surface of the base.
[0018] FIG. 7 is a side elevational schematic view of the prism tripod without the transponder attached.
[0019] FIG. 8 is a side perspective view of the laser holder showing the opening 132 .
[0020] FIG. 9 is a side perspective view of the laser together with the wire and switch
[0021] FIG. 10 is a side perspective view of the laser holder together with the laser installed in the opening defined within the laser holder showing the laser in the installed position.
[0022] FIG. 11 is a side perspective schematic elevational view of the prism tripod shown together with a laser holder and a prism mounted thereon along the cantilever axis and adjustable legs with ball ends.
[0023] FIG. 12 is a side perspective schematic elevational view of the prism tripod shown together with a laser holder and a prism mounted thereon along a central axis and adjustable legs with ball ends.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0024] Referring first of all to FIG. 3 , which shows the prism tripod generally as 100 together with a transponder 118 mounted thereon. Prism tripod 100 includes the following major components namely base 102 having a stationary leg 104 , two adjustable legs 106 each having a thumb screw head 108 for the purpose of manually turning adjustable legs 106 . Stationary leg 104 preferable terminates in a point 124 and also includes a prism extension 110 having a threaded end 140 all extending along point axis 190 .
[0025] Extending along cantilever axis 196 is a laser holder 112 having a threaded end 140 and an opening 132 for receiving a laser 126 therein. Laser 126 also includes a switch 128 in electrical communication with laser 126 with a wire 130 . A laser 126 projects a laser beam 134 terminating at laser point 136 when it impinges upon the desired surface.
[0026] Base 102 further includes a top surface 120 , a bottom surface 122 . Mounted on top surface 120 of base 102 is a set of bubble levels shown as 160 and 162 in FIG. 2 .
[0027] Base 102 has attached thereto a central post 114 extending along central axis 180 which has a handle 116 and a knob 146 at it's distal end.
[0028] Shown in FIG. 3 is a transponder 118 attached to central post 114 with a bracket 150 , which includes a thumbscrew 152 .
[0029] Laser 126 is shown in the installed position 210 housed within an opening 132 of laser holder 112 .
[0030] Additionally adjustable legs 106 are mounted and extend along adjustable leg axis 192 and 194 as shown in FIG. 1 .
[0031] FIG. 4 shows prism tripod 100 without transponder 118 mounted thereon and without bracket 150 mounted onto central post 114 .
[0032] FIG. 5 shows prisms 142 mounted onto threaded end of prism extension 110 and prism 144 mounted onto threaded end 140 of laser holder 112 .
[0033] In practice a prism would be mounted onto one or the other of threaded ends 140 but usually not two prisms on each end simultaneously. FIG. 6 is a bottom plan view of the bottom surface 122 of base 102 in particular FIG. 6 shows laser aperture 220 which is a fine hole through which laser beam 134 is projected in order to display a laser point 136 onto the surface on which it is pointed.
[0034] Referring now to FIGS. 8 , 9 and 10 , which show some of the details of laser holder 112 and laser 126 . FIG. 8 for example shows the laser holder 112 having a housing, which includes an opening 132 .
[0035] Opening 132 is sized to permit placement of laser 126 therein and into the installed position 210 shown in FIG. 10 .
[0036] Laser 126 includes a wire 130 and a switch 128 for manually turning laser 126 on and off.
[0037] FIG. 1 shows the geometrical relationships between a central axis 180 and point axis 190 adjustable leg axis 192 and adjustable leg axis 194 .
[0038] The circle 122 drawn about central axis 180 will meet tangentially at each of the triangle sides 178 triangle base 176 . Triangle 170 is an isosceles triangle having equi-length triangle sides 178 and triangle base 176 .
[0039] Perpendiculars 174 shown schematically in dashed lines which pass through central access 180 and meet the outer diameter circle 222 at the tangential intersection between circle 222 and the sides of triangle 170 as depicted in FIG. 1 .
[0040] The reader will note that perpendiculars 174 are in fact normal to each of the triangle sides 178 and triangle base 176 as depicted.
[0041] Referring now to FIGS. 11 and 12 an alternate embodiment showing prism tripod 300 which includes the following major components namely: base 302 having a top surface 320 and a bottom surface 322 . Base 302 being supported by edge adjustable legs 304 and a corner adjustable leg 305 . Each adjustable leg including thumb screws 317 and lock collars 319 for locking the adjustable legs into position.
[0042] Prism tripod 300 further including the bubble level 356 attached to the top surface 320 for levelling base 302 . Prism tripod 300 also including a central post 314 oriented along central axis 352 and a handle 316 attached to the central post for carrying prism tripod 300 .
[0043] Shown in FIG. 11 laser holder 312 having mounted thereon prism 344 is shown oriented along cantilever access 350 . Laser holder 312 is almost identical to laser holder 112 as described previously and houses laser 126 therein for creating a laser beam 134 and projecting a laser point 136 along cantilever access 350 .
[0044] As shown in FIG. 12 laser holder 312 can be positioned in three discreet positions namely along cantilever access 350 as shown in FIG. 11 along central access 352 as shown in FIG. 12 and along point access 354 not shown in FIG. 11 or 12 however shown in FIG. 5 .
[0045] Normally when laser holder 312 together with prism 344 is mounted along point access 354 corner adjustable leg 305 is replaced with a stationery leg 104 having a point 124 as shown in FIG. 3 .
[0046] In FIGS. 11 and 12 the adjustable legs 304 and corner adjustable legs 305 are shown with ball ends 306 . It is possible to use any combination of leg end including pointed ends as shown in FIG. 3 for example and/or a combination of ball ends 306 together with a pointed end 124 .
[0047] For example edge adjustable legs 304 could be fitted with ball ends 306 and corner adjustable leg 305 could be fitted with point 124 or corner adjustable leg 305 could be completely replaced with a stationary leg 104 having a point 124 as shown in FIG. 3 .
In Use
[0048] Referring to the prism tripod 300 shown in FIGS. 11 and 12 it is apparent to a person skilled in the art that laser holder 312 together with prism 344 can be placed in three discreet positions including along cantilever access 350 along central access 352 and also along point access 354 .
[0049] Base 302 includes a cantilever corner 360 which allows one to position base 302 over a point which one is wanting to lay out.
[0050] In other words should a surveyor wish to lay out a new point one would normally place laser holder 312 together with a prism 344 along cantilever access 350 such that the laser 126 can project a laser beam 134 and mark a laser point 136 in the desired location.
[0051] On the other hand if one is looking to determine the location of a pre-existing point one would rather place laser holder 312 along point access 354 and one would likely replace corner adjustable leg 305 with a stationary leg 104 having a point 124 . In this manner one could place point 124 onto the pre-existing point and determine it's location.
[0052] There is the other third configuration for prism tripod 300 namely laser holder 312 together with prism 344 could be installed along central access 352 . In this configuration one could lay out a point which falls in between the adjustable legs such as laying out points within circular tubes and other geometrical configurations which are much easier completed by placing laser holder 312 and prism 344 along central access 352 .
[0053] The reader will note that base 302 includes an unsupported cantilever portion 360 and a supported portion 361 . Supported portion 361 is defined by the area within triangle 170 . The unsupported portion is defined by the area outside triangle 170 and includes the cantilever portion 360 shown in FIG. 12 and also in FIG. 1 . Base 302 also includes other cantilever portions which are the portions outside of triangle 170 as shown in FIG. 1 . These other cantilever portions are not used in the presently preferred embodiment however could be used for other locations of laser holder 312 and prism 344 .
[0054] The reader will note that prism 344 which is alocating device could also include a GPS unit and/or a back sight or any other surveying type of locating device for demarcation layout and/or location of points. In this specification locating device refers to surveying instruments such as prisms, GPS's, back sights and the like.
[0055] Laser 126 is adapted to project a laser beam 134 downwardly shown as lower beam 393 and also upwardly shown as upper beam 391 . This beam can be projected upwardly and downwardly simultaneously or independently.
[0056] A surveyor using the prism tripod 100 or 300 as described above and depicted above will note immediately that it eliminates the need for hand holding of a prism pole and/or post. Tripod 100 and 300 operate in analogous fashion with some small differences which are discussed.
[0057] The prior art device is very similar to the stationery leg 104 together with the prism extension 110 and a prism 142 mounted thereon. The present device the prism tripod 100 rigidly attaches the components of a typical prism holding rod and/or post onto base 102 as shown in the figures in particular FIGS. 3 and 5 . By ensuring that prism extension 110 , stationery leg 104 having point 124 and prism 142 are carefully aligned along point axis 180 always ensures that prism 142 is aligned above point 124 . For example should the surveyor wish to determine the location of a particular point which has already been demarked in the field the surveyor could simply place point 124 of prism tripod 100 onto the demarked point and level base 102 using thumbscrew heads 108 which screwably right raise and lower adjustable legs 106 until such time as the user can visually see that base 102 is level according to bubble level 162 and bubble level 160 . Once point 124 is placed onto the demarked point and adjustable legs 106 are adjusted such that base 102 is level the user can then use the robotic total station to determine the location of prism 142 which in turn will tell the surveyor the exact location upon which point 124 is resting. Movement due to hand holding of a prism post and/or pole has been totally eliminated and errors in the location of a demarked point has been minimized.
[0058] On the other hand if a surveyor is seeking to lay out a particular point and mark the position of the point, the surveyor will place prism 144 on to the top of laser holder 112 namely onto threaded end 140 . Laser holder 112 and prism 144 will be aligned along cantilever axis 196 therefore ensuring that wherever the laser beam 134 projects a laser point 136 it is in alignment with the prism 144 .
[0059] In this manner the surveyor can manipulate prism tripod 100 until such time as a robotic total station will tell the user that prism 144 is directly above the desired location. The surveyor can then turn on laser point 136 by depressing switch 128 and thereby laser beam 134 will exactly impinge upon and mark with a laser point 136 the location of the point, which the surveyor wishes to demark.
[0060] The surveyor can then either use a stamp, ink, line, and/or any other marking tool to very accurately mark the location of laser point 136 which is the point that has been laid out by the surveyor.
[0061] In this process of course the user of prism tripod 100 will have levelled base 102 ming thumbscrew heads 108 thereby screwably raising and lowering adjustable legs 106 until such time as base 102 is level as indicated by bubble levels 160 and 162 .
[0062] It will be apparent to the reader that it is very simple and easy to demark a point in that even when a demarking tool such as a stamp or a pen or an ink line or a scribe is placed on the point one can visually determine very accurately that the mark being made is exactly at the point that has been surveyed. Additionally one is able to visually detect the location of the demarcation that has been made as either a scratch or an ink mark, after the mark has been made by ensuring that the laser point is directly on top and shines onto the mark that has been placed by the surveyor.
[0063] It should be apparent to persons skilled in the art of various modification and adaptations of the structure described above are possible without departure from the spirit of the invention the scope of which is defined in the appended claims. | A Prism Tripod includes a planar base including a supported portion and a cantilever portion. Preferably the base includes a cantilever axis, and a point axis, wherein the cantilever axis within the cantilever portion and the point axis within the supported portion. The prism tripod including at least three legs supporting the base and a laser holder for supporting a locating device and a laser. The base is adapted to demountably receive the laser holder along the cantilever axis, wherein the laser and locating device mounted along the cantilever axis. | 5 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to radio frequency (RF) devices and, more particularly, to an integrated balun and coupler transformer.
2. Description of the Background Art
A balun is a device designed to convert between balanced radio frequency (RF) signals and unbalanced RF signals, such as between twin-lead (balanced line) and coaxial cables (unbalanced line). A balun is typically implemented through the use of a small isolation transformer, with the earth ground or chassis ground left floating on the balanced side. In such a configuration, the balun can also perform impedance matching. For example, baluns are used in amplifiers having a push-pull configuration in order to convert the balanced output signal to an unbalanced signal.
A coupler is a transmission device for sampling (through a known coupling loss) the signal in a transmission line. For example, couplers are used in electronic devices, such as amplifiers, to monitor output signal level and feed a sample to the control logic (e.g., automatic gain control (AGC) logic or other type of monitor circuit for further processing).
Some electronic devices, such as the exemplary amplifiers described above, require both a balun and a coupler at their outputs. Conventionally, the balun and the coupler are two separate devices. As such, they take up significant space, contribute added insertion loss, and compromise the output impedance match.
SUMMARY OF THE INVENTION
One aspect of the invention relates to a radio frequency (RF) device having a balun and coupler. The balun includes a first winding and a second winding arranged on a magnetic core. Respective inputs of the first winding and the second winding are configured to receive a balanced RF input and respective outputs of the first winding and the second winding are configured to provide a first unbalanced RF output. The coupler includes a third winding arranged on the magnetic core. The third winding is configured to provide a second unbalanced RF output, where the second unbalanced RF output is a fraction of the first unbalanced RF output.
BRIEF DESCRIPTION OF DRAWINGS
So that the manner in which the above recited features of the present invention can be understood in detail, a more particular description of the invention, briefly summarized above, may be had by reference to embodiments, some of which are illustrated in the appended drawings. It is to be noted, however, that the appended drawings illustrate only typical embodiments of this invention and are therefore not to be considered limiting of its scope, for the invention may admit to other equally effective embodiments.
FIG. 1 is a schematic diagram depicting an exemplary embodiment of a radio frequency (RF) device constructed in accordance with one or more aspects of the invention;
FIG. 2 is a block diagram depicting an exemplary embodiment of an RF system having the RF device of FIG. 1 constructed in accordance with one or more aspects of the invention;
FIG. 3 is a perspective view depicting an exemplary embodiment of a structure for the RF device of FIG. 1 in accordance with one or more aspects of the invention; and
FIG. 4 is a top view of the structure of FIG. 3 with the top removed.
To facilitate understanding, identical reference numerals have been used, where possible, to designate identical elements that are common to the figures.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 is a schematic diagram depicting an exemplary embodiment of a radio frequency (RF) device 100 constructed in accordance with one or more aspects of the invention. The device 100 includes a balanced RF port 102 , an unbalanced RF port 104 , an unbalanced RF port 106 , a magnetic core 108 , and windings 110 , 112 , and 114 . The balanced RF port 102 includes a positive terminal 116 and a negative terminal 118 . The unbalanced RF port 104 includes a positive terminal 120 and a ground terminal 122 . The unbalanced RF port 106 includes a positive terminal 124 and a ground terminal 126 .
The winding 110 is arranged on the magnetic core 108 and coupled between the positive terminal 116 and the positive terminal 120 . The winding 112 is arranged on the magnetic core 108 coupled between the negative terminal 118 and the ground terminal 122 . The winding 114 is arranged on the magnetic core 108 coupled between the positive terminal 124 and the ground terminal 126 . The winding 110 includes N 1 turns, the winding 112 includes N 2 turns, and the winding 114 includes N 3 turns. In one embodiment, N 1 is equal to N 2 (i.e., the winding 110 has the same number of turns as the winding 112 ). N 3 is less than N 1 and N 2 . In one embodiment, the winding 114 includes a single turn (i.e., N 3 =1). For example, N 1 and N 2 may be between 5 and 10 turns, depending on the bandwidth required and the amount of coupling desired.
The balanced RF port 102 is configured to receive a balanced RF input signal. The RF device 100 converts the balanced RF input signal into an unbalanced RF output signal. The unbalanced RF port 104 provides the unbalanced RF output signal via magnetic coupling between the windings 110 and 112 through the magnetic core 108 . The unbalanced RF port 106 is configured to provide a sample of the unbalanced RF output signal provided by the unbalanced RF port 104 (i.e., a fraction of the unbalanced RF output signal) via magnetic coupling between the windings 112 and 114 through the magnetic core 108 . As is well known in the art, the particular fraction of the unbalanced RF output signal provided at the unbalanced RF port 106 is determined by the ratio of turns between the winding 112 and the winding 114 (e.g., ratio between N 2 and N 3 ). The arrangement of the winding 110 and the winding 112 on the magnetic core 108 provides a balun. The arrangement of the winding 114 on the magnetic core 108 provides a coupler. The balun and coupler share the same magnetic core.
The terminals 120 and 122 may comprise a connector (e.g., a coaxial cable connector) or may comprise the ends of the windings 110 and 112 , respectively. The terminals 124 and 126 may comprise a connector (e.g., a coaxial cable connector) or may comprise the ends of the winding 114 . The terminals 116 and 118 may comprise a connector or may comprise the ends of the windings 110 and 112 , respectively.
In this manner, the RF device 100 provides an integrated balun and coupler. The integrated balun and coupler may be used with various types of electronic devices that require conversion from balanced to unbalanced signals and sampling of RF output, e.g., for control purposes. When used with such electronic devices, the integrated balun and coupler of the invention saves space, reduces insertion loss, and reduces cost compared to the use of two separate components.
FIG. 2 is a block diagram depicting an exemplary embodiment of an RF system 200 constructed in accordance with one or more aspects of the invention. The RF system 200 includes a balanced source 202 , a balanced transmission line 203 , an unbalanced transmission line 205 , an unbalanced load 204 , an unbalanced transmission line 209 , a control circuit 206 , an integrated balun and coupler (the RF device 100 ). The balanced source 202 is coupled to the balanced transmission line 203 , which is coupled to the balanced RF port 102 . The balanced transmission line 203 may comprise a twin-lead transmission line or the like known in the art. The unbalanced load 204 is coupled to unbalanced transmission line 205 , which is coupled to the unbalanced RF port 104 . The control circuit 206 is coupled to the unbalanced transmission line 209 , which is coupled to the unbalanced RF port 106 . The unbalanced transmission lines 205 and 209 may comprise coaxial cable or the like known in the art.
The balanced source 202 is configured to provide a balanced RF signal. The balanced RF signal is coupled to the balanced RF port 102 via positive and negative lines of the balanced transmission line 203 . The RF device 100 converts the balanced RF signal to an unbalanced RF signal through magnetic coupling between the winding 110 and the winding 112 through the magnetic core 108 . The unbalanced RF signal is output from the unbalanced RF port 104 . The unbalanced RF signal is coupled to the unbalanced load 204 via positive and ground conductors of the unbalanced transmission line 205 . The RF device 100 also samples the unbalanced RF signal through magnetic coupling between the winding 112 and the winding 114 through the magnetic core 108 . The sample of the unbalanced RF signal is output from the unbalanced RF port 106 . The sample of the unbalanced RF signal is coupled to the control circuit 206 positive and ground conductors of the unbalanced transmission line 209 . For example, the RF system 200 may comprise an amplifier driving an unbalanced RF load. The control circuit 206 may comprise automatic gain control (AGC) circuitry for the amplifier.
FIG. 3 is a perspective view depicting an exemplary embodiment of a structure 300 for the RF device 100 in accordance with one or more aspects of the invention. In the structure 300 , the magnetic core 108 includes a generally body 350 having a top 301 , a bottom 305 , sides 310 and 312 , ends 302 and 304 , and bores 306 and 308 . The body 350 is generally shaped like a rectangular prism. The body 350 (and hence the magnetic core 108 ) may comprise ferrite. Each of the bores 306 and 308 traverses the length of the body 350 generally parallel to the sides 310 and 312 between the ends 302 and 304 . The bores 306 and 308 are positioned within the body 350 to define a central vane 314 . Each of the windings 110 , 112 , and 114 comprises a transmission line wrapped around the central vane 314 through the bore 306 and the bore 308 . FIG. 4 is a top view of the structure 300 with the top 301 removed to reveal the windings 110 , 112 , and 114 wrapped around the central vane 314 . The ends of each of the windings 110 , 112 , and 114 extend out from either the bore 306 or the bore 308 .
While the foregoing is directed to illustrative embodiments of the present invention, other and further embodiments of the invention may be devised without departing from the basic scope thereof, and the scope thereof is determined by the claims that follow. | Integrated balun and coupler is described. In one example, a radio frequency (RF) device includes a balun and coupler. The balun includes a first winding and a second winding arranged on a magnetic core. Respective inputs of the first winding and the second winding are configured to receive a balanced RF input and respective outputs of the first winding and the second winding are configured to provide a first unbalanced RF output. The coupler includes a third winding arranged on the magnetic core. The third winding is configured to provide a second unbalanced RF output, where the second unbalanced RF output is a fraction of the first unbalanced RF output. | 7 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is the national stage application of international patent application PCT/EP20111067141, filed Sep. 30, 2011, designating the United States and claiming priority from U.S. provisional application Ser. No. 61/388,240, filed Sep. 30, 2010, and German application 10 2010 047 846.6, filed Sep. 30, 2010, and the entire content of the above applications is incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] The invention relates to an optical lens, in particular for use as a spectacle lens, comprising a first lens element and at least one second lens element, wherein the first lens element and the second lens element at least partly act together in an achromatic fashion.
[0003] The invention furthermore relates to method for producing an optical lens, in particular for use as a spectacle lens.
[0004] Such an optical lens is known from the document GB 487 546 A, The optical lens described therein is used as a cataract lens. However, in principle, this lens can also be used as a spectacle lens.
[0005] It is generally known that if the spectacle lens is manufactured from only one lens element, spectacle lenses cause chromatic aberration as a result of the wavelength dependence of the refractive indices of the optical materials from which they are manufactured. The chromatic aberrations include the longitudinal colour aberration (also referred to as axial chromatic aberration or longitudinal chromatic aberration), which generates different foci for different wavelengths of the light. In addition to longitudinal colour aberration, there is also, as a further chromatic aberration, the transverse colour aberration (also referred to as colour magnification error or transverse chromatic aberration), which is expressed by coloured fringes or coloured edges in the image plane, which is the retina of the eye in the case of a spectacle lens; this is perceived by the spectacles wearer and considered an annoyance above a certain intensity.
[0006] In the case of spectacle lenses, chromatic aberrations, in particular the transverse chromatic aberration, will not be noticeable in an annoying fashion to the spectacles wearer in the case of spectacle lenses with a low power; however, the chromatic aberrations, particularly the transverse chromatic aberrations, increase in spectacle lenses with increasing optical power, independently of whether the defective eyesight to be corrected is based on myopia or hyperopia.
[0007] These days, highly-refractive materials, in particular plastics or highly-refractive types of glass, are often used to keep the spectacle-lens thickness as thin as possible for cosmetic reasons. However, precisely materials with a high refractive index have a significantly stronger transverse chromatic aberration because, in general, an increasing refractive index goes hand-in-hand with a lower Abbe number.
[0008] Thus, it is desirable at least to reduce such chromatic aberrations, in particular the transverse chromatic aberration, produced by a spectacle lens.
[0009] The field of objectives, e.g. for cameras, has disclosed the practice of correcting chromatic aberrations by so-called achromats. In optics, an achromat is understood to mean a system consisting of at least two lenses that consist of materials with different Abbe numbers and/or different refractive indices and hence differ in the dispersion behaviour. Of the two lenses, one is a positive lens, usually manufactured from a material with a higher Abbe number (e.g. crown glass), and the other lens is a negative lens made of a material with a lower Abbe number and hence greater dispersion than the positive lens, with this second lens for example being manufactured from flint glass.
[0010] The two lenses are shaped and interconnected on mutually complementary surfaces such that the chromatic aberration is compensated to the best possible extent for two wavelengths. The two lenses then act together achromatically.
[0011] Within the meaning of the present invention “at least partly” acting together “in an achromatic fashion” is understood to mean that the achromatic aberration or aberrations need not necessarily be eliminated completely, but is/are at least reduced.
[0012] The above-described conventional achromats are not suitable for use as spectacle lenses. Namely, since these achromats are assembled from two complete lenses, they also have a corresponding thickness and, going hand-in-hand with this, an excessive weight.
[0013] The lens disclosed in the document GB 487 546A mentioned at the outset consists of two lens elements that substantially have the same refractive index, of which the one lens element is manufactured from flint glass with a refractive index of approximately 1.61 and a reciprocal relative dispersion of approximately 36. The other lens element is manufactured from barium crown glass with a refractive index of approximately 1.61 and a reciprocal relative dispersion of approximately 50. The first-mentioned lens element is a negative lens element, and the lens element mentioned second is a positive lens element. The two lens elements are interconnected on mutually complementary surfaces.
[0014] The lens produced thus has a rear side, i.e. a side facing the eye of the wearer, that is entirely formed by the negative lens element, while the front side of the lens, i.e. the side facing away from the eye of the wearer, is partly formed by the surface of the positive lens and, in the margin region thereof, by the surface of the negative lens.
[0015] The lens is furthermore afflicted by the disadvantage that it consists of two complete lens elements and hence it is relatively thick and quite heavy.
[0016] The professional article “Hybrid diffractive-refractive achromatic spectacle lenses”, W. N. Charman, Opthal. Physiol. Opt. 1994, volume 14, pages 389 to 392 also considers the reduction of chromatic aberrations in spectacle lenses. It emphasizes that achromats that have a lens with a low refractive index and a high Abbe number and a lens with a high refractive index and a low Abbe number, of which the one lens is negative and the other is positive, are not practical as spectacle lenses because they are contrary to the desire of having spectacle lenses with a low thickness and a low weight. In order to resolve the disadvantages of achromats, it proposes to combine a refractive lens with a diffractive element, wherein the combination of the refractive lens and the diffractive element can substantially have the same thickness and the same weight as the refractive lens on its own.
[0017] However, a spectacle lens composed of a refractive lens and a diffractive element is very complex in terms of the production thereof since the diffractive element has to be produced with great precision in order to avoid that the diffractive element induces other aberrations.
BRIEF SUMMARY OF THE INVENTION
[0018] The invention is therefore based on the object of developing an optical lens of the type mentioned at the outset to the effect that the lens has the smallest possible thickness and the lowest possible weight despite having an at least partial achromatic effect.
[0019] According to the invention, this object is achieved in respect of the optical lens mentioned at the outset by virtue of the fact that the second lens element is configured as at least one lens segment that is only arranged in a margin region of the first lens element.
[0020] The optical lens according to the invention departs from the previously pursued concept of achieving an achromatic effect over the entire surface of the lens. Rather, the at least partial achromatic effect is restricted to the margin region of the lens in the case of the optical lens according to the invention, in other words, the optical lens according to the invention constitutes a partial achromat; i.e. if the optical lens is used as a spectacle lens, the spectacle lens is only achromatized in a margin region. The prior art has not considered that the transverse chromatic aberration in particular, which is expressed in the perception of coloured fringes, greatly increases from the centre of the spectacle lens, i.e. from its optical axis that corresponds to the direction of looking straight ahead, to the margin of the spectacle lens. Annoying coloured fringes are only noticed by the wearer of the spectacles when the viewing direction (visual angle) deviates strongly from the direction of looking straight ahead, i.e. if the wearer of the spectacles peers through the margin of the spectacle lens.
[0021] To this end, in the optical lens according to the invention, the second lens element is restricted to one or more lens segments that is/are only arranged in a margin region of the first lens element. By contrast, the second lens element is not present in the central region of the optical lens, which contains the optical axis, and so the lens can be constructed like in a conventional spectacle lens in this region.
[0022] The advantage of the optical lens according to the invention consists in the fact that the chromatic effect is controlled where it is strongest and noticeably perceived by the wearer of the spectacles, while the optical lens overall can substantially have the same thickness and the same weight as a spectacle lens without achromatization.
[0023] In a preferred embodiment, the at least one lens segment extends along the margin region of the first lens element over part of the circumference.
[0024] An advantage of this is that further weight can be saved by the at least one lens segment extending only over a partial region of the margin region of the first lens element, i.e. over part of the circumference. In this case, the at least one lens segment is to be provided at a site in the margin region of the first lens element at which achromatization of the lens is desired.
[0025] As an alternative to the embodiment mentioned above, the second lens element preferably has precisely one lens segment that extends along the margin region of the first lens element over the entire circumference.
[0026] An advantage of this is that the lens according to the invention is at least partly achromatized along the entire margin region.
[0027] In a further preferred embodiment, the second lens element is arranged on the rear side of the first lens element.
[0028] In this case, “rear side” designates the side of the lens facing the eye of the wearer.
[0029] Since optical lenses that are used as spectacle lenses usually have a concave curvature as seen from the eye of the wearer, this measure is advantageous in that the thickness of the optical lens is not excessively thick even in its margin region compared to conventional optical lenses, despite the presence of the second lens element in this margin region. An increase in the thickness is avoided in particular if the rear side of the first lens element is convex and the at least one lens segment of the second lens element is arranged in the vertex region of the rear side of the first lens element.
[0030] According to the invention, provision is also made for a method for producing an optical lens, in particular for use as a spectacle lens, comprising the steps of
providing a first lens element blank and a second lens element blank, wherein the second lens element blank is manufactured from a material, the Abbe number and/or refractive index of which differs from the Abbe number and/or the refractive index of the material of the first lens element blank, removing material from the second lens element blank until a second lens element is created from the second lens element blank, which second lens element is configured as at least one lens segment.
[0033] Thus, the second lens element blank can for example be provided as a bi-concave negative lens, from which the central region inside the margin region of this lens element blank is completely removed.
[0034] The at least one lens segment created thus can either be subsequently applied to the first lens element blank and be connected to the latter e.g. by cementing or, as provided in a preferred embodiment, the first and the second lens element blank are interconnected, in particular cemented to one another, before material is removed from the second lens element blank.
[0035] Hence, as per this measure, a “basic achromat” is firstly produced from the two lens element blanks and the partial achromat according to the invention is subsequently produced from this basic achromat by removing material from the second lens element blank.
[0036] In the process, preference is furthermore given to practice of, additionally, removing material from the first lens element blank in order to obtain a first lens element that has been processed in accordance with the prescription for correcting a defective eyesight.
[0037] In conjunction with the aforementioned measure, the material removal can be continued into the first lens element blank from the second lens element blank, wherein the processing of the first lens element blank serves as per the prescription for correcting a defective eyesight. In conjunction with this measure, the first lens element blank can be provided as an initially biconvex lens.
[0038] The method according to the invention for producing the optical lens according to the invention in the form of a partial achromat can be carried out in a particularly simple and cost-effective fashion using the aforementioned measures.
[0039] Further advantages and features emerge from the subsequent description and the attached drawing.
[0040] It is understood that the features that were mentioned above and that are yet to be explained below can be used not only in the respectively specified combination, but also in other combinations or on their own, without departing from the scope of the present invention.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0041] The invention will now be described with reference to the drawings wherein:
[0042] FIG. 1 shows a front view of a schematic illustration of an optical lens that is embodied as a partial achromat;
[0043] FIG. 2 shows the optical lens from FIG. 1 in a section along the line II-II in FIG. 1 ; and
[0044] FIG. 3 shows a pre-form of the optical lens from FIG. 1 for explaining a method for producing the optical lens from FIG. 1 .
DETAILED DESCRIPTION OF THE INVENTION
[0045] FIGS. 1 and 2 illustrate an optical lens, labelled with the general reference sign 10 , which is destined for use as a spectacle lens.
[0046] As per FIG. 1 , the lens 10 is illustrated as a lens with a circular margin 12 , However, it is understood that the present invention is not restricted to circular optical lenses; rather, the lens 10 can have any other, for example polygonal, in particular rectangular, oval or other, basic shape.
[0047] The lens 10 has a front side 14 and a rear side 16 . The rear side 16 is that side of the lens 10 that faces the eye of the wearer of the spectacles when the lens 10 is used as a spectacle lens. The curvatures of the front side 14 and rear side 16 , and the (central) thickness of the lens 10 , illustrated in FIG. 2 , should be understood to be exemplary.
[0048] The lens 10 has a first lens element 18 and a second lens element 20 .
[0049] In the shown exemplary embodiment, the first lens element 18 has a front surface 22 and a rear surface 24 . In the shown exemplary embodiment, the front surface 22 is convex and the rear surface 24 is concave. However, the convex-concave embodiment of the first lens element 18 in this case should only be understood as being exemplary, and the invention is not restricted to this.
[0050] Nor is the first lens element 18 restricted as to whether it has a positive or negative power. Rather, the first lens element 18 is, in terms of shape, material, polish, etc., matched to the optical effect required for correcting a defective eyesight in accordance with a customer-specific prescription.
[0051] The second lens element 20 is embodied in the form of at least one, here precisely one lens segment 26 , which is only arranged in a margin region 28 of the first lens element 18 .
[0052] Here, the lens segment 26 extends along the margin region 28 of the first lens element 18 over the entire circumference.
[0053] The lens segment 26 is arranged on the rear side 16 of the first lens element 18 .
[0054] The lens segment 26 is fixedly connected, e.g. by cementing, to the first lens element 18 along mutually complementary surfaces 30 , 31 of the first lens element 18 and the lens segment 26 . Since the surface 30 of the first lens element 18 is convex, the corresponding surface 31 of the lens segment 26 is concave. A rear side 32 of the lens segment 26 is likewise concave in this case, and so the lens segment 26 overall has a biconcave design. Hence the lens segment 26 has a negative optical power, while the first lens element 18 is positive at least in the margin region 28 thereof as a result of the biconvex design thereof at said location.
[0055] The second lens element 20 in the form of the lens segment 26 acts together at least partly achromatically with the first lens element 18 . The material of the first lens element 18 and the material of the second lens element 20 are to this end selected accordingly in terms of their Abbe numbers and/or refractive indices. In respect of the dispersion behaviour thereof, the second lens element 20 and the first lens element 18 are matched to one another such that the desired achromatic effect of the lens 10 is achieved in the margin region thereof.
[0056] Since the second lens element 20 in the form of the lens segment 26 is only present in the margin region 28 of the first lens element 18 , the rear side 16 of the lens 10 is substantially formed by the rear side of the first lens element 18 , i.e. there only is the first lens element 18 in a central region 34 .
[0057] The height h of the margin region 28 , over which the second lens element 20 extends in respect of an optical axis 36 , is dependent on the optical effect of the lens 10 , the utilized material, in particular the Abbe number thereof, the design of the lens 10 , i.e. whether the lens 10 is flat, curved, aspherical, etc., and the individual sensitivity of the wearer of the spectacles in which the lens 10 is utilized.
[0058] The aberrations important for spectacle lenses, such as spherical aberration, oblique astigmatism, etc., can be corrected, taking into account the material configuration of the lens 10 , by appropriate processing of the rear side 16 , for example by introducing an asphere, an atorus, a freeform etc.
[0059] With reference to FIG. 3 , the following text describes how the optical lens 10 can be produced.
[0060] The production method for producing the optical lens 10 firstly consists in manufacturing a “basic achromat”.
[0061] To this end, provision is made for a first lens element blank 40 and a second lens element blank 42 . In the illustrated exemplary embodiment, the first lens element blank 40 has a biconvex design and the second lens element blank 42 has a biconcave design.
[0062] The first lens element blank 40 and the second lens element blank 42 are subsequently interconnected, for example cemented, along two mutually complementary surfaces 44 of the first lens element blank 40 and 46 of the second lens element blank 42 .
[0063] The basic achromat 48 created thus is subsequently processed for producing the finished optical lens 10 .
[0064] To this end, material from the second lens element blank 42 is removed from a rear side 50 of the second lens element blank 42 , for example by means of usual material removal methods that are utilized in the production of spectacle lenses.
[0065] Here, the removal of material from the second lens element blank 42 does not finish at the surface 44 of the first element blank 40 ; rather, material is also removed from the first lens element blank 40 until a rear side 52 of the basic achromat 48 is created, which is illustrated in FIG. 3 by a dashed line and corresponds to the rear side 16 of the finished optical lens 10 as per FIG. 2 . The rear side 52 is then finished, e.g. lapped and polished.
[0066] Thus, by removing material from the second lens element blank 42 and into the first lens element blank 40 , the first lens element 18 and the second lens element 20 in the form of the lens segment 26 are created, which lens segment extends along the margin region 28 of the first lens element 18 over the entire circumference. | An optical lens ( 10 ), in particular for use as a spectacle lens, comprises a first lens element ( 18 ) and at least one second lens element ( 20 ), wherein the first lens element ( 18 ) and the second lens element ( 20 ) at least partly act together in an achromatic fashion. The second lens element ( 20 ) is configured as at least one lens segment ( 26 ) that is only arranged in a margin region ( 28 ) of the first lens element ( 18 ). Furthermore, a method for producing the optical lens ( 10 ) is described. | 6 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
Numerous deposit-forming substances are inherent in hydrocarbon fuels. These substances, when used in internal combustion engines, tend to form deposits on and around constricted areas of the engine contacted by the fuel. Typical areas commonly and sometimes seriously burdened by the formation of deposits include carburetor ports, the throttle body and venturies, engine intake valves, etc.
Deposits adversely affect the operation of the vehicle. For example, deposits on the carburetor throttle body and venturies increase the fuel to air ratio of the gas mixture to the combustion chamber thereby increasing the amount of unburned hydrocarbon and carbon monoxide discharged from the chamber. The high fuel-air ratio also reduces the gas mileage obtainable from the vehicle.
Deposits on the engine intake valves when they get sufficiently heavy, on the other hand, restrict the gas mixture flow into the combustion chamber. This restriction, starves the engine of air and fuel and results in a loss of power. Deposits on the valves also increase the probability of valve failure due to burning and improper valve seating. In addition, these deposits may break off and enter the combustion chamber possibly resulting in mechanical damage to the piston, piston rings, engine head, etc.
The formation of these deposits can be inhibited as well as removed by incorporating an active detergent into the fuel. These detergents function to cleanse these deposit-prone areas of the harmful deposits, thereby enhancing engine performance and longevity. There are numerous detergent-type gasoline additives currently available which, to varying degrees, perform these functions.
The use of detergent-type gasoline additives is complicated by a phenomenon termed "Octene Requirement Increase "("ORI"). In particular, with regard to automobile engines that require the use of nonleaded gasolines (to prevent disablement of catalytic converters used to reduce emissions), it has been found difficult to provide gasoline of high enough octane to prevent knocking and the concomitant damage which it causes. The chief problem lies in the area of the degree of octane requirement increase, herein called "ORI", which is caused by deposits formed by the commercial gasoline.
The basis of the ORI problem is as follows: each engine, when new, requires a certain minimum octane fuel in order to operate satisfactorily without pinging and/or knocking. As the engine is operated on any gasoline, this minimum octane increases and, in most cases, if the engine is operated on the same fuel for a prolonged period, will reach an equilibrium. This is apparently caused by an amount of deposits in the combustion chamber. Equilibrium is typically reached after 5,000 to 15,000 miles of automobile operation.
The octane requirement increase in particular engines used with commercial gasolines will vary at equilibrium from 5 to 6 octane units to as high as 12 or 15 units, depending upon the gasoline compositions, engine design and type of operation. The seriousness of the problem is thus apparent. A typical automobile with a research octane requirement of 85, when new, may after a few months of operation require 97 research octane gasoline for proper operation, and little unleaded gasoline of that octane is available. The ORI problem also exists in some degree with engines operated on leaded fuels. U.S. Pat. Nos. 3,144,311; 3,146,203; and 4,247,301 disclose lead-containing fuel compositions having reduced ORI properties.
The ORI problem is compounded by the fact that the most common method for increasing the octane rating of unleaded gasoline is to increase its aromatic content. This, however, eventually causes an even greater increase in the octane requirement.
This ORI problem is recognized to be particularly significant with fuels, especially unleaded fuels, containing hydrocarbyl-substituted polyamine fuel additives. Accordingly, while certain hydrocarbyl-substituted polyamine additives are well known in the art as excellent dispersant/detergent fuel additives which have been commercially successful in leaded gasolines, the ORI problem associated with these additives have prevented their commercial use in unleaded gasolines. Accordingly, it would be particularly advantageous to develop a fuel composition containing such hydrocarbyl-substituted polyamine additives which would reduce to an acceptable level the ORI associated with these additives.
The instant invention is directed to synergistic fuel compositions containing a hydrocarbyl-substituted amine or polyamine and a hydrocarbyl-terminated poly(oxyalkylene) monool. These compositions provide for an unexpected decrease in those deposits which have been correlated to ORI.
2. Prior Art
Hydrocarbyl-substituted polyamines useful as fuel additives are known in the art and are disclosed in U.S. Pat. Nos. 3,438,757; 3,565,804; 3,574,576; and 3,671,511.
Likewise, the use of poly(oxyalkylene) diols as an additive in fuel compositions is disclosed in U.S. Pat. No. 4,548,616 which discloses the use of block copolymers as an ORI additive. U.S. Pat. No. 3,756,793 discloses fuel compositions containing a combination of a hydrocarbyl polyamine with a polyether glycol and etherified and esterfied products thereof.
U.S. Pat. No. 4,160,648 discloses certain polyether carbamates as fuel additives possessing good ORI properties and further discloses that poly(oxyalkylene) monools and polyols display synergistic effects when combined with such polyether carbamates in fuel compositions.
However, these references neither disclose the combination of hydrocarbyl-substituted polyamines with a C 1 -C 30 hydrocarbyl-terminated poly(oxyalkylene) monool nor do any of these references teach that such a combination would synergistically result in lower ORI for such fuel compositions.
SUMMARY OF THE INVENTION
The present invention is directed toward a synergistic fuel composition which contains a hydrocarbyl-substituted amine or polyamine and a hydrocarbyl-terminated poly(oxyalkylene) monool. In particular, the present invention is directed to a fuel composition comprising a major portion of hydrocarbons boiling in the gasoline range and (a) from about 0.001% by weight to about 1.0% by weight of a hydrocarbyl-substituted amine or polyamine having an average molecular weight of about 750 to about 10,000 and also having at least one basic nitrogen atom, and (b) a hydrocarbyl-terminated poly(oxyalkyline) monool having an average molecular weight from about 500 to about 5,000 wherein said oxyalkylene group of the hydrocarbyl-terminated poly(oxyalkylene) monool is a C 2 to C 5 oxyalkylene group and the hydrocarbyl group of said hydrocarbyl-terminated poly(oxyalkylene) monool is a C l to C 30 hydrocarbyl group and wherein the weight percent of the hydrocarbyl-terminated poly(oxyalkylene) monool in the fuel composition ranges from about 0.01 to 100 times the amount of hydrocarbyl-substituted amine or polyamine.
The compositions of this invention provide for reduction in ORI as compared to fuel compositions containing only the hydrocarbyl-substituted amine or polyamine additive. Thus, in its method aspect, the instant invention is directed to a method of reducing the ORI of a fuel composition containing a hydrocarbyl-substituted amine or polyamine which comprises adding a hydrocarbyl-terminated poly(oxyalkylene) monool having a molecular weight of from about 500 to about 5,000 wherein said oxyalkylene of the hydrocarbyl-terminated poly(oxyalkylene) monool is a C 2 to C 5 oxyalkylene group and the hydrocarbyl group of said hydrocarbyl-terminated poly(oxyalkylene) monool is a C l to C 30 hydrocarbyl group and wherein the weight percent of the hydrocarbyl-terminated poly(oxyalkylene) monool in the fuel composition ranges from about 0.01 to 100 times the amount of hydrocarbyl-substituted amine or polyamine.
DETAILED DESCRIPTION OF THE INVENTION
As noted above, the fuel compositions of this invention contain a hydrocarbyl-substituted amine or polyamine and a hydrocarbyl-terminated poly(oxyalkylene) monool. These components are described in detail below:
A. Hydrocarbyl-Substituted Amines or Polyamines
The hydrocarbyl-substituted polyamines employed in this invention are well known and are disclosed in U.S. Pat. Nos. 3,438,757 and 3,394,576. A method for their preparation is found in U.S. Pat. Nos. 3,565,804 and 3,671,511; the disclosure of which is hereby incorporated by reference.
The hydrocarbyl-substituted amines employed in this invention are prepared by reacting a hydrocarbyl halide (i.e., chloride) with ammonia or a primary or secondary amine to produce the hydrocarbyl-substituted amine.
The hydrocarbyl-substituted amines and polyamines are high-molecular-weight hydrocarbyl-N-substituted amines or polyamines containing at least one basic nitrogen. The hydrocarbyl group has an average molecular weight in the range of about 750-10,000 more usually in the range of about 1000-5000.
The hydrocarbyl radical may be aliphatic or alicyclic and, except for adventitious amounts of aromatic structure in petroleum mineral oils, will be free of aromatic unsaturation. The hydrocarbyl groups will normally be branched-chain aliphatic, having 0-2 sites of unsaturation, and preferably from 0-1 site of ethylene unsaturation. The hydrocarbyl groups are preferably derived from petroleum mineral oil, or polyolefins, either homopolymers or higher-order polymers, or 1-olefins of from 2-6 carbon atoms. Ethylene is preferably copolymerized with a higher olefin to insure fuel solubility.
Illustrative polymers include polypropylene, polyisobutylene, poly-1-butene, etc. The polyolefin group will normally have at least 1 branch per 6 carbon atoms along the chain, preferably at least 1 branch per 4 carbon atoms along the chain. These branched-chain hydrocarbons are readily prepared by the polymerization of olefins of from 3-6 carbon atoms and preferably from olefins of from 3-4 carbon atoms.
In preparing the compositions of this invention, rarely will a single compound having a defined structure be employed. With both polymers and petroleum-derived hydrocarbon groups, the composition is a mixture of materials having various structures and molecular weights. Therefore, in referring to molecular weight, average molecular weights are intended. Furthermore, when speaking of a particular hydrocarbon group, it is intended that the group include the mixture that is normally contained within materials which are commercially available. For example, polyisobutylene is known to have a range of molecular weights and may include small amounts of very high molecular-weight materials.
Particularly preferred hydrocarbyl-substituted amines or polyamines are prepared from polyisobutenyl chloride.
The polyamine employed to prepare the hydrocarbyl-substituted polyamine is preferably a polyamine having from 2 to about 12 amine nitrogen atoms and from 2 to about 40 carbon atoms. The polyamine is reacted with a hydrocarbyl halide (i.e., chloride) to produce the hydrocarbyl-substituted polyamine, employed in this invention. The polyamine is so selected so as to provide at least one basic amine in the hydrocarbyl-substituted polyamine. The polyamine preferably has a carbon-to-nitrogen ratio of from about 1:1 to about 10:1.
The amine portion of the hydrocarbyl-substituted amine may be substituted with substituents selected from (A) hydrogen, and (B) hydrocarbyl groups of from 1 to about 10 carbon atoms.
The polyamine portion of the hydrocarbyl-substituted polyamine may be substituted with substituents selected from (A) hydrogen, (B) hydrocarbyl groups of from 1 to about 10 carbon atoms, (C) acyl groups of from 2 to about 10 carbon atoms, and (D) monoketo, monohydroxy, mononitro, monocyano, lower alkyl and lower alkoxy derivatives of (B) and (C). "Lower", as used in terms like lower alkyl or lower alkoxy, means a group containing from 1 to about 6 carbon atoms.
At least one of the nitrogens in the hydrocarbyl-substituted amine or polyamine is a basic nitrogen atom, i.e., one tetratable by a strong acid.
Hydrocarbyl, as used in describing the amine or polyamine substituents of this invention, denotes an organic radical composed of carbon and hydrogen which may be aliphatic, alicyclic, aromatic or combinations thereof, e.g., aralkyl. Preferably, the hydrocarbyl group will be relatively free of aliphatic unsaturation, i.e., ethylenic and acetylenic, particularly acetylenic unsaturation. The substituted polyamines of the present invention are generally, but not necessarily, N-substitutd polyamines. Exemplary hydrocarbyl groups and substituted hydrocarbyl groups include alkyls such as methyl, ethyl, propyl, butyl, isobutyl, pentyl, hexyl, octyl, etc., alkenyls such as propenyl, isobutenyl, hexenyl, octenyl, etc., hydroxy alkyls, such as 2-hydroxyethyl, 3-hydroxypropyl, hydroxyisopropyl, 4-hyroxybutyl, etc., ketoalkyls, such as 2-ketopropyl, 6-ketooctyl, etc., alkoxy and lower alkenoxy alkyls, such as ethoxyethyl, ethoxypropyl, propoxyethyl, propoxypropyl, 2-(2-ethoxyethoxy)ethyl, 2-(2-(2-ethoxyethoxy)ethoxy)ethyl, 3,6,9,12-tetraoxatetradecyl, 2-(2-ethoxyethoxy)hexyl, etc.
Typical amines useful in preparing the hydrocarbyl-substituted amines employed in this invention include methylamine, dimethylamine, ethylamine, diethylamine, n-propylamine, di-n-propylamine, etc. Such amines are either commercially available or are prepared by art recognized procedures.
The polyamine component also may contain heterocyclic polyamines, heterocyclic substituted amines and substituted heterocyclic compounds, wherein the heterocycle comprises one or more 5-6 membered rings containing oxygen and/or nitrogen. Such heterocycles may be saturated or unsaturated and substituted with groups selected from the aforementioned (A), (B), (C) and (D). The heterocycles are exemplified by piperazines, such as 2-methylpiperazine, 1,2-bis-(N-piperazinyl)ethane, and N,N'-bis(N-piperazinyl)piperazine, 2-methylimidazoline, 3-aminopiperidine, 2-aminopyridine, 2-(betaaminoethyl)-3-pyrroline, 3-aminopyrrolidine, N-(3-aminopropyl)morpholine, etc. Among the heterocyclic compounds, the piperazines are preferred.
Typical polyamines that can be used to form the compounds of this invention include the following: ethylene diamine, 1,2-propylene diamine, 1,3-propylene diamine, diethylene triamine, triethylene tetramine, hexamethylene diamine, tetraethylene pentamine, methylaminopropylene diamine, N-(betaaminoethyl)piperazine, N,N'-di(betaaminoethyl)piperazine, N,N'-di(betaaminoethyl)imidazolidone-2, N-(beta-cyanoethyl)ethane-1,2-diamine, 1,3,6,9-tetraaminooctadecane, 1,3,6-triamino-9-oxadecane, N-methyl-1,2propanediamine, 2-(2-aminoethylamino)-ethanol.
Another group of suitable polyamines are the propyleneamines, (bisaminopropylethylenediamines). Propyleneamines are prepared by the reaction of acrylonitrile with an ethyleneamine, for example, an ethyleneamine having the formula H 2 N(CH 2 CH 2 NH) Z H wherein Z is an integer from 1 to 5, followed by hydrogenation of the resultant intermediate. Thus, the product prepared from ethylene diamine and acrylonitrile would be H 2 N(CH 2 ) 3 NH(CH 2 ) 2 NH(CH 2 ) 3 NH 2 .
In many instances the polyamine used as a reactant in the production of hydrocarbyl-substituted polyamine of the present invention is not a single compound but a mixture in which one or several compounds predominate with the average composition indicated. For example, tetraethylene pentamine prepared by the polymerization of aziridine or the reaction of dichloroethylene and ammonia will have both lower and higher amine members, e.g., triethylene tetramine, substituted piperazines and pentaethylene hexamine, but the composition will be largely tetraethylene pentamine and the empirical formula of the total amine composition will closely approximate that of tetraethylene pentamine. Finally, in preparing the hydrocarbyl-substituted polyamines for use in this invention, where the various nitrogen atoms of the polyamine are not geometrically equivalent, several substitutional isomers are possible and are encompassed within the final product. Methods of preparation of polyamines and their reactions are detailed in Sidgewick's "The Organic Chemistry of Nitrogen", Clarendon Press, Oxford, 1966; Noller's "Chemistry of Organic Compounds", Saunders, Philadelphia, 2nd Ed., 1957; and Kirk-Othmer's "Encyclopedia of Chemical Technology", 2nd Ed., especially Volumes 2, pp. 99-116.
The preferred hydrocarbyl-substituted polyalkylene polyamines for use in this invention may be represented by the formula ##STR1## wherein R l is hydrocarbyl having an average molecular weight of from about 750 to about 10,000; R 2 is alkylene of from 2 to 6 carbon atoms; and a is an integer of from 0 to about 10.
Preferably, R l is hydrocarbyl having an average molecular weight of from about 1,000 to about 10,000. Preferably, R 2 is alkylene of from 2 to 3 carbon atoms and a is preferably an integer of from 1 to 6.
B. Hydrocarbyl-terminated Poly(oxyalkylene) Monools.
The hydrocarbyl-terminated poly(oxyalkylene) polymers employed in the present invention are monohydroxy compounds, i.e., alcohols, often termed monohydroxy polyethers, or polyalkylene glycol monohydrocarbylethers, or "capped" poly(oxyalkylene) glycols and are to be distinguished from the poly(oxyalkylene) glycols (diols), or polyols, which are not hydrocarbyl-terminated, i.e., not capped. The hydrocarbyl-terminated poly(oxyalkylene) alcohols are produced by the addition of lower alkylene oxides, such as ethylene oxide, propylene oxide, the butylene oxides, or the pentylene oxides to the hydroxy compound R 3 OH under polymerization conditions, wherein R 3 is the hydrocarbyl group which caps the poly(oxyalkylene) chain. Methods of production and properties of these polymers are disclosed in U.S. Pat. Nos. 2,841,479 and 2,782,240 and the aforementioned Kirk-Othmer's "Encyclopedia of Chemical Technology", Volume 19, p. 507. In the polymerization reaction a single type of alkylene oxide may be employed, e.g., propylene oxide, in which case the product is a homopolymer, e.g., a poly(oxyalkylene) propanol. However, copolymers are equally satisfactory and random copolymers are readily prepared by contacting the hydroxyl-containing compound with a mixture of alkylene oxides, such as a mixture of propylene and butylene oxides. Block copolymers of oxyalkylene units also provide satisfactory poly(oxyalkylene) polymers for the practice of the present invention. Random polymers are more easily prepared when the reactivities of the oxides are relatively equal. In certain cases, when ethylene oxides is copolymerized with other oxides, the higher reaction rate of ethylene oxide makes the preparation of random copolymers difficult. In either case, block copolymers can be prepared. Block copolymers are prepared by contacting the hydroxyl-containing compound with first one alkylene oxide, then the others in any order, or repetitively, under polymerization conditions. A particular block copolymer is represented by a polymer prepared by polymerizing propylene oxide on a suitable monohydroxy compound to form a poly(oxypropylene) alcohol and then polymerizing butylene oxide on the poly(oxyalkylene) alcohol.
In general, the poly(oxyalkylene) polymers are mixtures of compounds that differ in polymer chain length. However, their properties closely approximate those of the polymer represented by the average composition and molecular weight.
The polyethers employed in this invention can be represented by the formula
R.sub.4 O--R.sub.3 O--.sub.p H
wherein R 4 is a hydrocarbyl group of from 1 to 30 carbon atoms; R 3 is a C 2 to C 5 alkylene group; and p is an integer, such that the molecular weight of the polyether is from about 500 to about 5,000.
Preferably, R 3 is a C 3 or C 4 alkylene group.
Preferably, R 4 is a C 7 -C 30 alkylphenyl group.
Preferably, the polyether has a molecular weight of from about 750 to about 3,000; and more preferably from about 900 to about 1,500.
C. Fuel Compositions
The fuel employed in the fuel compositions of the instant invention is generally a hydrocarbon distillate fuel boiling in the gasoline range. The hydrocarbyl-substituted amine or polyamine as well as the hydrocarbyl-terminated poly(oxyalkylene) monool are generally added directly to the fuel at the desired concentrations. The hydrocarbyl-substituted amine or polyamine is added at a dispersant/detergent amount and in general at from about 0.001% by weight to about 1.0% by weight to the fuel, although preferably, at from about 0.02% by weight to about 0.1% by weight. The hydrocarbyl-terminated poly(oxyalkylene) monool is added to this composition at an amount to reduce ORI. In general, the hydrocarbyl-terminated poly(oxyalkylene) monool is added at from about 0.01 to 100 times the amount of hydrocarbyl-substituted amine or polyamine, although preferably at from about 1 to 50 times.
In gasoline fuels, other fuel additives may also be included, such as anti-knock agents, e.g., methylcyclopentadienyl manganese tricarbonyl, tetramethyl or tetraethyl lead, or other dispersants or detergents such as various substituted succinimides, amines, etc. Also included may be lead scavengers, such as aryl halides, e.g., dichlorobenzene or alkyl halides, e.g., ethylene dibromide. Additionally, antioxidants, metal deactivators and demulsifiers may be present.
The following examples are offered to specifically illustrate this invention. These examples and illustrations are not to be construed in any way as limiting the scope of this invention.
EXAMPLES
EXAMPLE 1
Preparation of Dodecylalkylphenyl-poly(oxybutylene)monool
A dried 5-liter, 3-neck round bottom flask fitted with a chilled water reflux condenser and mechanical stirrer was charged with 487 g (1.85 moles) of dodecylalkylphenol and 21.7 g (0.56 moles) of metallic potassium. The mixture was heated at 65° C. with stirring under a nitrogen atmosphere until metallation was complete. The pot temperature was then raised to 85° C. and 3980 ml (46.3 moles) of 1,2-epoxybutane was added at such a rate to maintain gentle reflux. After adding all the 1,2-epoxybutane, the pot temperature was raised to 115° C. to complete the reaction as indicated by no further refluxing. The reaction was cooled to approximately 70° C. and 350 cm 3 of Dowex hydrogen ion exchange resin was added to the reaction with stirring. After stirring approximately 45 minutes, the reaction was filtered through a medium porosity sintered glass Buchner filter funnel with the aid of vacuum to afford 2682 g of the title compound as a golden oil: molecular weight approximately 1500, hydroxyl number=36.
EXAMPLE 2
Preparation of N-Polyisobutylenyl Ethylene Diamine
A 1-liter, 3-neck round bottom flask was charged with 150 g of polyisobutylene, average molecular weight approximately 950, and 160 ml of carbon tetrachloride and fitted with a chilled water condenser, gas dispersion tube and mechanical stirrer. The mixture was cooled to between 0°-5° C. with an ice-salt bath and 8.1 g (0.23 moles) of chlorine gas introduced via the gas dispersion tube at a rate of approximately 250 ml per minute with vigorous stirring. After adding the chlorine, the reaction was degassed with a nitrogen stream for 10 minutes and then stripped in-vacuo to afford 158.2 g of polybutene chloride containing 4.5 wt % chlorine.
A 250-ml, single-neck round bottom flask was charged with 75 g polybutene chloride (containing 0.96 moles of chlorine), 5 ml of xylenes, 21 ml of n-butanol and 26.6 ml (0.397 moles) of ethylenediamine. This flask was fitted with a Dean Stark distillation head, magnetic stir bar and the reaction mixture heated to 100° C. over approximately 20 minutes with vigourous stirring under a nitrogen atmosphere. The pot temperature was then raised to 150° C. and allowed to reflux for 30 minutes. The pot temperature was then raised to 160° C. and 21 ml of distillate (bp 130° C.) collected. The reaction was cooled to room temperature and transferred to a separatory funnel with the aid of toluene and washed with water until the water washings were neutral (pH paper). The use of n-butanol was required during washing to aid in decreasing emulsion formation. The organic layer was then dried over anhydrous potassium carbonate, filtered and stripped invacuo to afford 70.8 g of the title compound as a golden oil containing 1.71% basic nitrogen and 1.77% total nitrogen.
EXAMPLE 3
A method for determining whether or not a fuel additive is prone to causing ORI is to determine the residue it leaves behind in the thermal gravimetric analysis (TGA) experiment. In the TGA experiment, those additives which show less residue after being heated in an air atmosphere tend to be less prone to causing ORI.
The TGA procedure employed Du Pont 951 TGA instrumentation coupled with a microcomputer for data analysis. Samples of the fuel additives (Approximately 25 milligrams) were heated isothermally at 300° C. under air flowing at 60 cubic centimeters per minute. The weight of the sample was monitored as a function of time. Incremental weight loss is considered to be a first order process. Kinetic data, i.e., rate constants and half-lives, were readily determined from the accumulated TGA data. The half-life measured by this procedure represents the time it takes for half of the additive to decompose. Half-life data for a fuel additive correlates to the likelihood that that additive will contribute to ORI. Lower half-lives represent a more easily decomposable product--one which will not as likely accumulate and form deposits in the combustion chamber.
The compositions tested contained varying ratios of a dodecylphenyl poly(oxyalkylene) alcohol ("A") (prepared in a manner similar to that of Example 1) having an average molecular weight of approximately 1500 and a polyisobutenyl ethylene diamine ("B") (prepared in a manner similar to that of Example 2) having an average molecular weight of approximately 1500.
The weight loss of the compositions are shown in Table I below:
TABLE I______________________________________ Calculated Weight Loss Without Weight Weight Any Synergism Loss (%) Loss (%) PresentSample After 4 Min. After 30 Min. (After 30 Min.)______________________________________100% B 17 37 --100% A 99 99 --50% A/50% B 30 92 6825% B/75% A 94 98 83.510% B/90% A 99 99 92.8______________________________________
The above data establishes thast the compositions of the instant invention synergetically provide for a reduction in those deposits which have been correlated to ORI. | Disclosed is a synergistic fuel composition containing a hydrocarbyl-substituted amine or polyamine and a poly(oxyalkylene) monool. These compositions provide for an unexpected decrease in those deposits which have been correlated to Octane Requirement Increase (ORI). | 2 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The invention relates to a method for producing a plurality of measurement regions on a chip, wherein electrically contactable electrode pairs are structured on the chip in each of the measurement regions and wherein the measurement regions are formed by producing a compartmental structure which separates the measurement regions from one another.
[0003] 2. Description of Related Art
[0004] Moreover, the invention relates to a chip having a plurality of electrically addressable measurement regions, wherein a compartmental structure which separates the measurement regions from one another is provided on the surface of the chip.
[0005] A chip of the kind described hereinbefore and a method of producing it is known, for example, from U.S. Patent Application Publication 2009/0131278 A1. The chip is a silicon-based chip on the surface of which are provided a plurality of electrode pairs by metalizing and structuring. These pairings are in a two-dimensional array, preferably a chessboard arrangement. The electrode arrangements consist of electrode strips meshing with one another which ensure that the two electrodes of the electrode arrangement are adjacent to one another over a long distance.
[0006] The measurement regions are provided for functionalizing with certain biologically active substances. These may be, for example, antibodies which react chemically to specific antigens, these chemical reactions being electrically detectable by means of the electrode arrangement. Functionalization is carried out by a so-called spotting process, in which each measurement region is acted upon by another, e.g., water-based solution. The molecules responsible for the functionalization on the corresponding measurement regions are thereby immobilized. It is crucially important that the different liquids in the individual measurement regions are not mixed with one another, to ensure that only one type of relevant molecules is present on each measurement region.
[0007] To prevent the liquids of adjacent spots from being mixed together, it is proposed according to from U.S. Patent Application Publication 2009/0131278 A1 that mechanical barriers in the form of small walls may be provided between the individual measurement regions. The surface of the chip is thus divided into different compartments of a box, so to speak, the liquids each being “poured” into one of these compartments during the spotting process. However, it should be taken into consideration that the compartments present on the chip surface are of an order of magnitude in the μm range. Therefore, the effect of the mechanical boundaries comes up against its limits. As a result of the surface tension of the solvent, such as water, it may happen that in spite of the mechanical boundaries the liquids of adjacent measurement regions combine and thus the relevant functional molecules are mixed together.
SUMMARY OF THE INVENTION
[0008] The object of the invention is to provide a method for producing a plurality of measurement regions on a chip, as well as a chip which can be produced by this method in particular, while at least substantially preventing liquids from mixing together during the spotting process.
[0009] The above problem is solved by a method and a chip as described herein.
[0010] It goes without saying that features, embodiments, advantages and the like which are mentioned hereinafter only in connection with one aspect of the invention, to avoid repetition, nevertheless also apply accordingly to the other aspects of the invention.
[0011] It also goes without saying that in the statements of values, numbers and ranges provided hereinafter, the values or ranges specified should not be interpreted in a restrictive capacity; the skilled man will understand that deviations may occur from the specified ranges and figures, as a result of individual cases or in relation to particular applications, without departing from the scope of the present invention.
[0012] Moreover, it is the case that all the values or parameters or the like specified hereinafter may be determined or ascertained by standardized or explicitly stated methods of determination or by methods of determination which are familiar to the skilled man. Subject to this, the present invention will now be described in more detail.
[0013] According to one aspect of the present invention, the formation of the compartmental structure is preferably carried out using the following process steps. First, hydrophilic properties are produced in the measurement regions. This is a necessary prerequisite for wetting the measurement regions with a hydrophilic liquid. Generally, the functional molecules are dissolved in water, and for this reason the hydrophilic properties of the measurement regions are of supreme importance. Moreover, the method according to the invention comprises producing hydrophobic wetting properties on the surface of the chip outside the measurement regions by applying a self-organized monolayer consisting of a fluorosilane compound. Examples of possible fluorosilane compounds include Teflon (polytetrafluoroethylene or PTFE). For example, (tridecafluoro-1,1,2,2-tetrahydrooctyl) trichlorosilane C8H4Cl3F13Si may be used. Advantageously, the hydrophobic effect of this monolayer is far more effective than a mechanical barrier. Owing to the fact that the chip surface between the measurement regions is virtually impossible to wet with hydrophilic liquids, a safety interval is produced between the individual spots of the functional liquids, which effectively prevents mixing. Therefore, reliably functionalized chips can advantageously be produced by the method according to the invention.
[0014] According to another aspect of the present invention, in particular, a chip is proposed in which the compartmental structure is formed from a self-organized (self-assembling) monolayer, consisting of a fluorosilane compound, which covers the chip surface outside the measurement regions.
[0015] A monolayer is formed when only one layer of molecules is formed on the chip surface. The self assembly of the monolayer is caused by the structure of the fluorosilane compound used. The fluorosilane molecules comprise a trichlorosilane group which has a high affinity for silicon, which is why this group is provided on the surface of the chip. The remainder of the molecules are then distanced from the surface, and form a surface which is comparatively hydrophobic. This hydrophobic action on the surface is advantageously highly effective.
[0016] According to an embodiment of the method according to the invention, the method is carried out using the following steps in the order specified, in order to form the compartmental structure. First, a fluorosilane compound is vapor-deposited on the chip surface as a monolayer. This takes place in a vacuum atmosphere. CVD or PVD processes may be used. Then a photo-structurable coating is applied to the chip surface. This initially covers the whole of the chip surface. Next, the measurement regions are illuminated through a suitable mask. By developing the photo-structurable coating, a photo-structured coating is formed in which the measurement regions can be exposed. In the measurement regions thus exposed, hydrophilic properties are generated so that the aqueous solutions can be spotted onto them. Finally, the photo-structurable coating is removed.
[0017] According to an alternative embodiment of the invention, the method for forming the compartmental structure may also be carried out using the following process steps in the order specified. First the hydrophilic properties are generated over the entire chip surface. Then a photo-structurable coating is applied to the chip surface. This can be photo-structured by illuminating the surface of the chip outside the measurement regions. A photo-structured coating is produced by developing the photo-structurable coating, the measurement regions being covered by the photo-structured coating. Then a fluorosilane compounds is vapour-deposited in a monolayer on the surface of the chip, in the manner already mentioned. Finally, the photo-structured coating is removed.
[0018] The two alternative processes have the major advantage that the individual production steps are well known per se and can therefore be carried out with considerable process reliability. Therefore, by improving the process reliability, high quality results are advantageously obtained.
[0019] According to another embodiment of the process, it is provided that the production of the hydrophilic properties is carried out in an oxygen plasma or by dry etching. These methods, which are conventional in the processing of wafers, are also advantageously carried out with high process reliability.
[0020] According to a further embodiment of the invention it is provided that, after the end of the process steps as described above, the processed chip surface is cleaned. In this way the chip surface can be prepared for a subsequent spotting process. Contamination is advantageously eliminated so that after spotting no measurement errors occur as a result of a contaminated surface of the measurement regions. The cleaning of the processed chip surface may form the end of the preparation of the chips. These chips are then packaged so that no further cleaning of the chip surface is required. The user will then only remove the packaging just before the spotting process is carried out. Alternatively, it is, or course, also possible for the cleaning to be carried out by the user at the last possible moment before the spotting process.
[0021] The cleaning is preferably carried out by a wet chemical method. The use of a piranha solution is recommended. This consists of a mixture of hydrogen peroxide and sulphuric acid and constitutes a highly effective compound for cleaning the surface. Advantageously, the monolayer of fluorosilane compounds is sufficiently chemically stable to withstand this cleaning step.
[0022] According to a further embodiment of the invention it is also possible for the functionalization of the measurement regions by a spotting process to be carried out immediately after the cleaning has taken place. In this case the user is provided with the already functionalized chips. This is advantageous in analytical processes which are very often used as standard, as the chips can be functionalized in large numbers immediately after manufacture. This satisfactorily prevents contamination during the process.
[0023] According to another aspect of the present invention, a method for producing a chip having a plurality of electrically addressable measurement regions or for producing a plurality of measurement regions on a chip is proposed, in which electrically contactable electrode pairings are structured in each of the measurement regions on the chip and the measurement regions are formed by producing a compartmental structure which separates the measurement regions from one another.
[0024] The formation of the compartmental structure comprises the production of hydrophobic wetting properties on the surface of the chip outside the measurement regions. Moreover, the formation of the compartmental structure may include the production of hydrophilic properties in the measurement regions.
[0025] Furthermore, according to an aspect of the present invention which can be achieved independently, the measurement regions are provided with a protective coating at least substantially until the chip is incorporated in an electric component. By the expression “until the chip is incorporated” is meant the process step in the manufacture of the chip in which removal of the protective coating makes sense. This may be immediately before the spotting process, but may also, for example, be immediately after the cutting of the wafer from which the chip is made, or after the electrical contacting (bonding) of the (individual) chip.
[0026] The use of a protective coating which at least substantially covers the measurement regions makes further processing of the chip easier. The chip, or the wafer from which the chip is made, may for example be divided up or electrically connected or provided with passivation on the outside or cast, without any risk of the delicate measurement regions or areas of the chip vapor-coated with metals such as gold, being exposed to mechanical, thermal or chemical stresses and being damaged or even destroyed.
[0027] Within the scope of the present invention, particularly good results are obtained if the protective coating is a photo-structured coating or a photoresist. Photo-structured coatings are generally obtainable from photo-structurable coatings. By a photo-structurable coating is meant, within the scope of the present invention, a coating the aggregate state and/or chemical nature of which is altered by the effects of electromagnetic radiation, particularly UV radiation, thus producing a photo-structured coating. In particular, it is provided in this context that only the regions of the photo-structurable coating which are exposed to the electromagnetic radiation are subject to change. The change in the protective coating induced by the effect of electromagnetic radiation may be in particular such that the coating becomes fixed or liquefies, is chemically cured, i.e. cross-linked, or polymeric structures are destroyed. Thus, by the use of masks and UV radiators, for example, structures can thus be produced on the surface of the chip.
[0028] In this context it may be envisaged that the photo-structured coating contains a photoresist or is a photoresist. Photoresists which usually cure under the effect of UV radiation are known per se to the skilled man and are commercially available in large numbers.
[0029] Within the scope of the present invention it is preferable if the photo-structured coating is a photoresist which is also used within the scope of rendering the chip surface hydrophobic. In this way, time, materials and equipment can be saved within the scope of the present invention, as the photo-structured coating applied in the course of producing the hydrophobic finish, particularly the photoresist, also remains on the measurement regions for protecting the measurement regions even after the hydrophobic finish has been applied and continues to protect these regions up to the time of installation or until the processing of the chip has been complete.
[0030] If a photo-structured coating is used as a protective coating for the within the scope of the present invention, it is preferable if the photo-structured coating, particularly the photoresist, is chemically and/or physically stable at least for short periods at temperatures up to 150° C., particularly 200° C., preferably 250° C., preferably 300° C. During the processing of the chip, for example during the cutting process or installation into devices, it may happen over and over again that the chip is subjected to thermal peaks, i.e. short-lived thermal stresses. In this case, the photo-structured coating or the photoresist must not decompose chemically, nor can the chemical or physical nature change so that the measurement regions are no longer adequately protected, or the coating is no longer removable at a later stage.
[0031] For this reason, the protective coating or the photo-structured coating applied should be sufficiently thermally stable, particularly at the temperature peaks which occur briefly during the processing of the chip.
[0032] Thermally resistant photo-structured coatings or photoresists of this kind are advantageously formed on the basis of polyamide, within the scope of the present invention. Polyamide-based photoresists often have a decidedly high thermal stability of up to 400° C. and may furthermore be hydrophobic.
[0033] Generally, the hydrophobic treatment is carried out within the scope of the present invention by applying a hydrophobic coating to the chip. In this context, it may be that the hydrophobic coating is applied to the chip in the form of a layer of lacquer or a monolayer. If the hydrophobic coating is applied as a layer of lacquer, this may refer particularly to photo-structured coatings, particularly photoresists, which cure or depolymerise or are destroyed by electromagnetic radiation, particularly UV radiation. When, within the scope of the present invention, the hydrophobic coating is formed by a photoresist, and in particular the photoresist is applied to the chip by one of the methods described above, there is no need for any further hydrophobic treatment of the surface of the chip. In this case, the hydrophobic photoresist remains outside the measurement regions on the chip and is not removed again. If, on the other hand, the hydrophobic coating is formed by a monolayer, it has proved satisfactory within the scope of the present invention if the monolayer is applied as a self-assembling monolayer. Monolayers produce particularly sharply delimited hydrophobic regions on the chip.
[0034] Similarly within the scope of the present invention it may also be provided that the hydrophobic treatment is carried out by reacting with reactive chemical compounds. Preferably, the reactive chemical compounds used within the scope of the present invention are silanes, particularly alkylsilanes and/or fluorosilanes. When alkylsilanes are used within the scope of the present invention, it has proved suitable to use trialkylsilanes or silazanes as alkylsilanes, preferably trimethylchlorosilane and/or hexamethyldisilazane. If, on the other hand, fluorosilanes are used within the scope of the present invention, it has proved satisfactory to use partially fluorinated or perfluorinated silanes, most preferably tridecafluoro- 1,1,2,2-tetrahydrooctyl-trichlorosilane.
[0035] The use of fluorosilanes is particularly preferred as they have not only outstanding hydrophobic properties but also excellent chemical resistance.
[0036] For further details on the process according to the invention, reference may be made to the foregoing remarks on the other aspects of the invention which apply equally to the method according to the invention.
[0037] In respect of other details regarding the method according to the invention, reference may be made to the remarks concerning the other aspects of the invention which apply equally to the method according to the invention.
[0038] Finally, according to a fourth aspect of the present invention, the invention also relates to a chip having a plurality of measurement regions, which can be obtained by the method described hereinbefore.
[0039] For further details on the chip according to the invention, reference may be made to the foregoing remarks on the other aspects of the invention which apply equally to the chip according to the invention.
[0040] Further details of the invention are described hereinafter by reference to the drawings. Identical or corresponding elements of the drawings have been given the same reference numerals in the figures and their explanations are only repeated where there are differences between the individual figures.
BRIEF DESCRIPTION OF THE DRAWINGS
[0041] FIGS. 1 to 4 show selected steps of a first embodiment of the method according to the invention,
[0042] FIGS. 5 to 7 show selected manufacturing steps of another embodiment of the method according to the invention,
[0043] FIG. 8 shows a detail of the surface of the chip of an embodiment of the chip according to the invention as a three-dimensional view, and
[0044] FIG. 9 shows a schematic representation of the chip in the connected and installed state.
DETAILED DESCRIPTION OF THE INVENTION
[0045] FIG. 1 shows the detail of a chip 11 made of silicon. However, the chip 11 may also be made of a different material.
[0046] Particularly preferably, the chip 11 comprises or contains electronic circuits and/or electrode arrangements 23 not shown in FIG. 1 (cf. FIGS. 8 and 9 ).
[0047] The chip 1 preferably has a hydrophobic coating 12 which may take the form of a monolayer and/or may preferably contain or be formed from a fluorosilane compound.
[0048] Preferably, a fluorosilane compound, particularly as described above, has first been vapour deposited on the chip 11 in a desiccator, in the course of which the fluorosilane compound has formed a self-assembled monolayer 12 on the chip surface 13 . After this, a photo-structurable coating 14 has been applied to the monolayer 12 . Using a perforated mask 15 , the regions that are intended to form the measurement regions 16 subsequently are illuminated with light 17 (cf. also FIG. 4 ).
[0049] FIG. 2 shows the photo-structured coating 18 after the photo-structurable coating 14 has been developed. In this way, the hydrophilic regions which subsequently produce the measurement regions 16 are defined. They appear as windows 19 in the photo-structured coating 18 .
[0050] FIG. 3 shows how the hydrophilic regions have been produced in the oxygen plasma. The monolayer 12 has been removed in the region of the windows 19 , apart from the chip surface 13 . In this way the hydrophilic measurement regions 16 are formed. Then the photo-structured coating 18 has also to be removed from the monolayer 12 . This can be seen in FIG. 4 . FIG. 4 also shows how different liquids 20 a, 20 b are applied to the measurement regions 16 in order to functionalize these measurement regions (spotting method). In this way the finished functionalized chip 11 is produced.
[0051] The method according to FIGS. 5 to 7 also works with a photo-structurable coating 14 and a hydrophobic coating or a monolayer 12 (cf. FIG. 6 ). However, the order of application of these two coatings is precisely reversed, compared with the method described according to FIGS. 1 to 4 . According to FIG. 5 , first of all, the photo-structurable coating 14 is applied to the surface 13 of the chip 11 .
[0052] For structuring the photo-structurable coating 14 , an illuminating mask 21 is preferably used which consists of a transparent sheet and has a lightproof coating 22 in the region of what will subsequently be the measurement regions 16 . The photo-structurable coating 14 is structured by means of the light 17 .
[0053] As can be seen from FIG. 6 , the photo-structured coating 18 remains in the measurement regions 16 , while the surrounding areas have been exposed right down to the surface of the chip 13 . These regions are then coated with the hydrophobic coating or self-assembling monolayer 12 , particularly of fluorosilanes.
[0054] As can be seen from FIG. 7 , the photo-structured coating 18 is then removed, exposing the measurement regions 16 . These are located directly on the chip surface 13 . The functionalizing of the measurement regions 16 , as described previously, is carried out by a spotting process in which the liquids 20 a, 20 b are applied.
[0055] Alternatively, the measurement regions 16 may also only be exposed later. The measurement regions 16 are then protected by the photo-structurable coating 14 or the photo-structured coating 18 , i.e., by a protecting coating, or by a photoresist or the like which forms it, for example, until the chip 11 has been separated from other chips (not shown) of a wafer or the like, and/or until the chip 11 has been electrically connected (bonded) and/or provided with a passivation layer on the outside and/or cast into position or installed in a housing.
[0056] To form the photo-structurable coating 14 it is particularly preferable to use a photoresist. Particularly preferably, a polyamide-based photoresist is used, especially on account of its thermal stability.
[0057] According to another alternative, the structurable or structured coating 14 , 18 or the photoresist is preferably used instead of the monolayer 12 or fluorosilane compound to form the hydrophobic layer 12 or compartmental structure 24 . The photo-structurable coating 14 , as indicated in FIG. 5 , then forms the hydrophobic layer or coating in the desired regions and hence the compartmental structure 24 or intermediate regions 27 . The method is thereby simplified, as preferably only the coating 14 or the photoresist has to be removed to form the measurement regions 16 , i.e. there is no need to apply a second coating. In this case the photoresist is then preferably of a correspondingly hydrophobic nature or can be rendered hydrophobic by an alternative method.
[0058] FIG. 8 shows a detail of the edge of a measurement region 16 on the chip surface 13 . The measurement region 16 comprises an electrode pairing or arrangement 23 which preferably consists of a first electrode 23 a and a second electrode 23 b. These electrodes preferably comprise fingers which preferably mesh with one another. This electrode arrangement 23 reacts with great sensitivity to the fact that functional molecules (not shown in detail) which are immobilized in the measurement region 16 , react with molecules that are to be detected.
[0059] The measurement region 16 is also surrounded by a compartmental structure 24 , only a detail of which is shown. Part of this detail is shown on a larger scale, showing that the compartmental structure 24 is preferably formed from the layer or monolayer 12 . This consists particularly of molecules of the fluorosilane compound, these molecules being docked with their functional group 25 on the surface 13 of the chip 11 , whereas the molecular residue 26 which produces the highly hydrophobic properties of the monolayer 12 projects upwardly or away from it.
[0060] Preferably, the compartmental structure 24 or the hydrophobic coating 12 —particularly on its free surface—forms a hydrophobic intermediate region 27 between the (adjacent) measurement regions 16 , so that liquids 20 a, 20 b not shown in FIG. 8 do not flow into adjacent measurement regions 16 or mix or combine fluidically with adjacent liquids during spotting, i.e. during the application of drops of liquid to the measurement regions 16 , particularly for immobilizing scavenger molecules or the like (not shown).
[0061] The compartmental structure 24 or the hydrophobic coating 12 or the respective intermediate region 27 is therefore preferably hydrophobic, particularly strongly hydrophobic.
[0062] Particularly preferably, the contact angle of the compartmental structure 24 or the hydrophobic coating 12 or the intermediate regions 27 with water is at least substantially 90°, preferably more than 120°, most preferably more than 150°, in each case measured under normal conditions with distilled water.
[0063] FIG. 9 shows, in a highly diagrammatic plan view, the proposed chip 11 in the connected, installed state, or the chip 11 with or in a housing 28 .
[0064] Preferably, the chip 11 together with other chips 11 is produced in a conventional process, for example by the CMOS method, on a common carrier or substrate, particularly a so-called wafer. Then the chips 11 are separated from one another, connected electrically and preferably installed, particularly in an associated housing 28 or the like.
[0065] In the embodiment shown, the chip 11 is preferably electrically connected to contact surfaces or terminals 29 , particularly by electrical connections 30 indicated by dashed lines. This is only schematically shown here. The electrical connection of the chips 11 is usually referred to as bonding.
[0066] In the installed state, at least the measurement regions 16 are accessible for receiving samples (not shown) that are to be measured.
[0067] FIG. 9 shows the compartmental structure 24 which with its intermediate regions 27 or hydrophobic layers 12 (completely) surrounds the measurement regions 16 and/or separates them from one another. In particular, a lattice-like or honeycomb-shaped structure is formed, each measurement region 16 preferably being annularly defined.
[0068] As already mentioned, the measurement regions 16 may be covered or protected by a protective layer, particularly a coating 14 , particularly preferably of photoresist. This protective coating is then preferably not removed until after the cutting or division of the chips 11 and/or after the electrical connection and/or installation of the chip 11 in question. However, it is also possible to expose the measurement regions 16 earlier.
[0069] If the removal of the protective layer does not take place until after installation, the protective layer is particularly preferably configured to be of sufficient thermal stability. In fact, for installation, the chip 11 is cast into position, in particular. Because of the temperatures occurring, a conventional photoresist may harden. This would at least make it difficult, if not completely impossible, to remove it from the measurement regions 16 at a later stage. Therefore, preferably, a photoresist is used which is sufficiently thermally stable without hardening. A polyamide-based photoresist is particularly suitable for this purpose.
[0070] FIG. 9 schematically shows an electrode arrangement 23 in only one measurement region 16 , namely in the lower right-hand measurement region 16 . In particular, electrode arrangements 23 of this kind which are preferably identical or similar, are formed or arranged in all the measurement regions 16 .
[0071] The electrode arrangements 23 are preferably formed before the production or application of the compartmental structure 24 .
[0072] The electrode arrangements 23 are preferably located at least substantially in the chip surface 13 on which the measurement regions 16 are formed and the compartmental structure 24 is created.
[0073] The chip surface 13 is preferably configured to be at least substantially flat and/or preferably constitutes a flat side of the chip 11 .
[0074] In the embodiment shown, the hydrophobic layers 12 or intermediate regions 27 preferably adhere to one another and/or form a cohesive lattice. However, they may also form separate regions or portions on the chip surface 13 which surround or enclose one or more measurement regions 16 .
[0075] Preferably, different molecules for detection may be detected in the measurement regions 16 by means of the electrode arrangements 23 . Corresponding detection signals are emitted electrically, in particular, by the chip 11 or can preferably be interrogated electrically.
[0076] Preferably, the compartmental structure 24 is raised relative to the at least substantially flat ship surface 13 .
[0077] Preferably, the compartmental structure 24 surrounds each measurement region 16 completely or annularly with the hydrophobic layer 12 of the hydrophobic intermediate region 27 .
[0078] In particular, the compartmental structure 24 or hydrophobic layer 12 or monolayer or the intermediate region 27 is of lattice-like or honeycomb-shaped configuration.
[0079] The compartmental structure 24 or hydrophobic layer 12 or intermediate regions 27 is or are preferably embodied as a flat and/or planar coating.
[0080] Preferably, the compartmental structure 24 or hydrophobic layer 12 or the intermediate region 27 is smaller in height than width. Particularly preferably, the width between two adjacent measurement regions 16 is greater than the height relative to the chip surface 13 carrying the measurement regions 16 by a factor of at least 5, preferably by a factor of at least 10.
[0081] Particularly preferably, the height of the compartmental structure 24 or hydrophobic layer 12 or the hydrophobic intermediate region 27 is less than 2 μm, more particularly less than 1 μm, and/or more than 10 nm, particularly more than 100 nm.
[0082] Particularly preferably, the intermediate regions 27 have a width between the measurement regions 16 of more than 10%, particularly more than 20%, particularly preferably about 50% or more, of a measurement region 16 .
[0083] Particularly preferably, the intermediate regions 27 have a width between the measurement regions 16 of more than 5 μm, particularly more than 10 μm or 20 μm, particularly preferably more than 50 μm.
[0084] The measurement regions 16 preferably have a width or an average diameter of more than 50 μm, particularly more than 100 μm, and/or less than 500 μm, preferably less than 300 μm, particularly less than 200 μm, most particularly preferably about 120 to 180 μm.
[0085] Preferably, during the so-called spotting, drops of liquid 20 a, 20 b are applied to the individual measurement regions 16 , particularly each having a volume of 1,000 to 2,000 pl, while the hydrophobic layers 12 or intermediate regions 27 ensure that the drops of liquid 20 a, 20 b remain in place on the respective measurement region 16 and do not mix with adjacent drops of liquid 20 a, 20 b and/or do not flow into an adjacent measurement region 16 .
[0086] The above-mentioned spotting may theoretically be carried out as desired, either before or after the division of the chips 11 and/or the electrical connection and installation of the chip 11 in question. Preferably, the spotting takes place after the connection and installation of the chips 11 .
[0087] The spotting or application of drops of liquid 20 a, 20 b serves, in particular, only to functionalize the individual measurement regions 16 , i.e., particularly to precipitate or bind special molecules for trapping or reacting with molecules that are to be detected in a sample. The drops of liquid are removed again, in particular, after a desired immobilization or binding of the special molecules. Thus, spotting also serves in particular to prepare the chip 11 or the measurement regions 16 .
[0088] The sample liquid itself, containing molecules that are to be measured or detected, is subsequently applied to the chip 11 or the measurement regions 16 —for example over the entire surface and/or using a membrane which covers, as flatly as possible, the measurement regions 16 with the sample liquid located thereon—when the chip 11 is used correctly. The membrane may interact with the compartmental structure 24 , in particular may lie on it, in order to distribute the sample liquid over the measurement regions 16 and/or to achieve fluidic separation of the sample liquid in the various measurement regions 16 from one another.
[0089] However, alternatively, it is also possible to apply one or more samples that are to be measured to the previously functionalized measurement regions 16 by spotting.
[0090] Individual aspects and features of the various embodiments, variants and alternatives may also be implemented independently of one another, but also in any desired combination. | A a chip and a method for producing the chip with a plurality of measurement regions which are provided with electrodes for electrically detecting reactions in which, in order to reliably separate the individual measurement regions from one another, a monolayer of a fluorosilane is formed on the chip surface which has strongly hydrophobic properties. Therefore, during spotting with a liquid, the drops of liquid applied by spotting can be reliably prevented from coalescing, and thus, causing mixing of the substances in the drops of liquid which are supposed to be immobilized in the measurement regions. | 1 |
RELATED APPLICATION
[0001] This nonprovisional application claims the benefit of co-pending, provisional patent application U.S. Ser. No. 60/882,471, filed on Dec. 28, 2006, which is hereby incorporated by reference in its entirety.
TECHNICAL FIELD
[0002] The present invention relates generally to methods and systems for reservoir simulation and history matching, and more particularly, to methods and systems for calibrating reservoir models to conduct forecasts of future production from the reservoir models.
BACKGROUND OF THE INVENTION
[0003] One way to predict the flow performance of subsurface oil and gas reservoirs is to solve differential equations corresponding to the physical laws that govern the movement of fluids in the subsurface. Because of the nature of the problem, the differential equations are conventionally solved using numerical methods working in discrete representations in space and time. Solving such equations typically requires the use of three dimensional, discrete representations of the subsurface rock properties and the associated fluids in the rocks.
[0004] In the oil and gas industry, numerical methods to solve for the flow of fluids in the reservoir are called “Numerical Reservoir Simulation”, or simply “Flow Simulation”. Predictions of future performance of subsurface oil and gas reservoirs with models based on physical laws are considered the highest standard in current technology. The three dimensional, discrete models of the subsurface are constructed in such a way that the models are consistent with actual measurements taken from the reservoir. Some of these measurements can be included directly in the model at the time of the construction. Other measurements, such as ones that are related to the movement of fluids within the reservoir, are used in an indirect manner utilizing a model calibration process. The calibration process involves assigning properties to the model and then verifying that the solutions computed with a numerical reservoir simulator are consistent with the measurements of the fluids. This calibration process is iterative and stops when the reservoir model is able to replicate the observations within a predetermined tolerance. Once the model is appropriately calibrated, the model can be run in a flow simulator to forecast or predict future performance.
[0005] The process of calibrating numerical models of oil and gas reservoirs to measurements related to production and/or injection of fluids is usually referred to as history matching. The calibration problem described previously may be considered as being a particular case within the field of inverse problem theory in mathematics. While there exists a rigorous mathematical framework for the solution of model calibration problems, such a framework becomes impractical for dealing with complex problems such as large scale reservoir flow simulation. For a detailed explanation of such a framework, see A. Tarantola, Inverse Problem Theory—Methods for Data Fitting and Model Parameter Estimation , Elsevier, 1987, hereinafter referred to as “Tarantola”. This Tarantola reference is hereby incorporated by reference in its entirety into this specification.
[0006] There are numerous difficulties in calibrating numerical models of oil and gas reservoirs to data related to the movement of fluids within the reservoirs. First, numerical models based on laws of physics are usually complex and a significant amount of computational time is required to evaluate, i.e. run a simulation on, each numerical model. Data to calibrate the numerical models are often uncertain. Furthermore, data to calibrate numerical models are scarce, both in time and space dimensions. Finally, there is not a unique solution to the calibration problem. Rather, there are many ways to calibrate a numerical model that is still consistent with all the measurements. Thus, there is not a unique calibrated numerical model. Accordingly, a probability is associated with any combination of model parameters and this probability may be expressed such as by using a probability density function (PDF).
[0007] The mathematical inverse problem theory provides the framework to deal with the inverse problem presented by reservoir flow simulation. Tarantola describes the mathematical theory applicable to the problem of calibration and uncertainty estimation. The solution to the problem is based on application of techniques relying on Monte Carlo simulation. The general approach prescribed by the mathematical theory, as described by Tarantola, can be summarized with a high level of simplification as follows.
[0008] A parameterization system, comprising model parameters, is defined for a mathematical model. Initially, an “a priori” probabilistic description is defined for the model parameters describing the mathematical model. Next, a probabilistic model is defined for measured or observed data which is to be used for calibration. This probabilistic model is constructed by defining a measure of the discrepancy between actual observed measurements of parameters and corresponding calculated parameters predicted by using the mathematical model. This measure of discrepancy is associated with a “likelihood” function in a Bayesian approach to updating probabilities. Then an “a posteriori” probabilistic description of the model parameters is constructed by updating the “a priori” probabilistic model using the observed measurements. In the most general case, the model parameter space is sampled in such a way that the resulting probability density function provides the desired “a posteriori” probabilistic description of the model parameters. The sampling takes into account the “a priori” model description. A common approach for performing the sampling is the application of variants of the Metropolis algorithm for Monte Carlo sampling. This process also produces probability density functions that correspond to the predictions calculated with the reservoir model.
[0009] The step of sampling the model parameter space is the most computational demanding part of this process and limits the practical application of this rigorous mathematical approach to solving problems involving oil and gas reservoir models based on physical laws. Using terminology commonly associated with inverse problem theory, the process involves solving the “forward problem” (running the flow simulation) a very large number of times during the sampling of the parameter space. The “forward problem” refers to computing the model response to a given combination of input model parameters.
[0010] Tarantola describes the use of probability theory in inverse problems such as in history matching and production forecasting. Likelihood functions need to be computed in the applications described by Tarantola. A likelihood function is a measure of how good results from a simulation run on a proposed model are as compared to actual observed values. Computation of likelihood functions in conjunction with very large models, such as are used in reservoir simulations, are not practical due to great computational costs. Evaluation of a likelihood function requires a reservoir simulation run. Each run of a large reservoir simulation may require hours of time to complete. Furthermore, thousands of such simulations may be required to obtain valid results.
[0011] There is a need for a practical method for history matching and forecasting wherein the high computational costs associated with calculating likelihood functions are reduced to a manageable level. The present invention addresses this need.
SUMMARY OF THE INVENTION
[0012] A method, system and program storage device for history matching and forecasting of subterranean reservoirs is provided. Reservoir parameters and probability models associated with a reservoir model are defined. A likelihood function associated with observed data is also defined. A usable likelihood proxy for the likelihood function is constructed. Reservoir model parameters are sampled utilizing the usable proxy for the likelihood function and utilizing the probability models to determine a set of retained models. Forecasts are estimated for the retained models using a forecast proxy. Finally, computations are made on the parameters and forecasts associated with the retained models to obtain at least one of probability density functions, cumulative density functions and histograms for the reservoir model parameters and forecasts. The system carries out the above method and the program storage device carries instructions for carrying out the method.
[0013] It is an object of the present invention to substitute low computational cost, non-physics based likelihood proxies for likelihood functions while applying inverse problem theory to calibrate reservoir simulation models and to forecast production from such calibrated simulation models.
[0014] It is another object to create likelihood proxies for likelihood functions which are used in history matching of reservoir simulation models with actual production data.
[0015] It is yet another object to build a likelihood proxy for a likelihood function that optimizes the number of flow simulations required to achieve a predetermined level of accuracy in approximating the true likelihood function.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] These and other objects, features and advantages of the present invention will become better understood with regard to the following description, pending claims and accompanying drawings where:
[0017] FIG. 1 is a flowchart of a preferred embodiment of a production forecasting method made in accordance with the present invention;
[0018] FIG. 2 is a flowchart of the construction of a usable likelihood proxy LP for a likelihood function L;
[0019] FIG. 3 is a flow chart describing steps in selecting sets or vectors a of model parameters m representative of reservoir models in constructing usable likelihood proxies LP;
[0020] FIG. 4 is a graph depicting how a likelihood proxy LP is constructed for an associated likelihood function L;
[0021] FIG. 5 is a flow chart describing steps taken in constructing a usable forecast proxy FP used to forecast results from selected reservoir models; and
[0022] FIG. 6 is a flow chart describing the process for generating forecasts and associated statistics using a generic Monte Carlo sampling.
DETAILED DESCRIPTION OF THE INVENTION
[0023] The present invention provides a method to calibrate numerical models of subsurface oil and gas reservoirs to measurements related directly and indirectly to the production and/or injection of fluids from and/or into the reservoirs. Further, the present invention provides a method for estimating the uncertainty associated with future performance of the oil and gas reservoirs after the calibration of the numerical models.
[0024] Probabilistic descriptions can be obtained which are conditional to observed data related to the movement of fluids within the subsurface, for both the mathematical models used to represent actual oil and gas reservoirs and for the predictions of future performance computed using such models. Both model description and predictions are ideally conveyed by way of approximated probability density functions (PDF's) conditioned to the observed data. The probabilistic description of both the reservoir model and predictions (forecasts) are of significant importance to decision processes related to reservoir production based on risk analysis.
[0025] FIG. 1 is a flowchart of steps taken in a preferred embodiment of the present invention. High level steps will first be described. Then, these high level steps will be described in greater detail, often using other flow charts.
[0026] First, reservoir models, which include reservoir geologic models and reservoir flow simulation models, are defined in steps 50 and 70 , respectively, for one or more subterranean reservoirs. Reservoir model parameters, i.e., a set or vector a of parameters m i , characteristic of geologic and flow simulation properties, observed data d obs and probability models associated with the reservoir parameters m i and observed data d obs are defined in step 100 . A likelihood function L is then defined for flow simulation models in step 200 . A usable likelihood proxy LP is constructed in step 300 to approximate the likelihood function L. A usable forecast proxy FP is then constructed in step 400 . Next, a sampling is performed in step 500 on sets α of reservoir parameters m to obtain a set of retained reservoir models. A forecast is estimated in step 600 for each of the retained reservoir models using the usable forecast proxy FP. Finally, statistics, such as probability density functions (PDF's), cumulative density functions (CDF's) and histograms, are computed for the forecasts and for the sets a of reservoir parameters m.
[0027] One or more geologic models are created in step 50 in a process generally referred to as reservoir characterization. These geologic models are ideally three-dimensional, discrete representations of subsurface formations or reservoirs of interest which contain hydrocarbons such as oil and/or gas. Of course, the present invention could also be used with 2-D or even 1-D reservoir models. Examples of data used in constricting a geological model may include, by way of example and not limitation, seismic imaging, geological interpretation, analogs from other reservoirs and outcrops, geostatistics, well cores, well logs, etc. Data related to the flow of fluids in the reservoirs are typically not used in the construction of the geological models. Or if this data is used, it is generally only used in a minor way.
[0028] Reservoir flow simulation models are created in step 70 , generally one flow simulation model for each geologic model. These flow simulation models are to be run using a flow simulator program, such as Chears™, a proprietary software program of Chevron Corporation of San Ramon, Calif. or Eclipse™, a software program publicly available from Schlumberger Corporation of Houston, Tex. Those skilled in the art will appreciate that the present invention may also be practiced using many other simulator programs as well. These simulator programs numerically solve differential equations governing the flow of fluids within subsurface reservoirs and in wells that fluidly connect one or more subsurface reservoirs with the surface. Inputs for the flow simulation model typically include three dimensional, discrete representations of rock properties. These rock properties are obtained either directly from the geological model defined in step 50 or else through a coarsening process, commonly referred to as “scale-up”. Inputs for the flow simulation model typically also include the description of properties for fluids, the interaction between fluids and rocks (i.e. relative permeability, capillary pressure, etc), and boundary and initial conditions.
[0029] Reservoir models, i.e., vectors α of parameters m, observed data d obs and their associated probability models are defined in step 100 . The reservoir model, which includes the geologic and flow simulation models, is parameterized with a vector a of reservoir model parameters m. A non-limiting exemplary list of reservoir model parameters m includes:
[0000] (a) geological, geophysical, geostatistical parameters and, more generally, the same input parameters for algorithms invoked in the workflow used to construct the geological and/or flow simulation models, i.e., water-oil contacts, gas oil contacts, structure, porosity, permeability, fault transmissibility, histograms of these properties, variograms of these properties, etc. The reservoir model parameters m can be defined at different scales. For example, some parameters may affect the reservoir model at the scale used to construct a geological model, and others can affect a flow simulation model which results from the process of coarsening (scale-up). The coarsening process produces the flow simulation model used for computation of movement of fluids within the subsurface reservoir. For an example of a reservoir model parameterization system at the level of a Geological Model, see Jorge Landa, Technique to Integrate Production and Static Data in a Self - Consistent Way , SPE 71597 (2001) and Jorge Landa and Sebastien Strebelle, (2002), Sensitivity Analysis of Petrophysical Properties Spatial Distributions, and Floss Performance Forecasts to Geostatistical Parameters Using Derivative Coefficients , SPE 77430, 2002;
(b) parameters related to the description of the fluids properties in the reservoir (i.e. viscosity, saturation pressure, etc), parameters affecting the interaction between reservoir rock and reservoir fluids (i.e., relative permeability, etc), and well properties such as skin, non-darcy effects, etc.
[0030] A first “a priori” probabilistic model is defined for the vector α of reservoir model parameters m defined above. This probabilistic model could be as simple as a table defining the maximum and minimum values that each of the parameters m may take, or as complex as a joint probability density function (PDF) for all the reservoir model parameters m. The a priori probabilistic model defines the state of knowledge about the vector α reservoir model parameters m before taking into consideration data related to the movement of fluids in the reservoir or reservoirs.
[0031] A second probabilistic model is defined for observed data d obs . This observed data d obs will later be used to update the a priori probability reservoir model parameters m. The second probabilistic model for the observed data d obs ideally takes into consideration the errors in the measurements of the observed data d obs and the correlation between the measurements of the observed data d obs . The second probabilistic model may also include effects related to limitations due to approximations to the true physical laws governing the reservoir model.
[0032] A typical example for the second probabilistic model for the observed data d obs is a multi-Gaussian model with a covariance matrix C d . Of course, those skilled in the art of data analysis will appreciate that there are other possible data models which could be used as the second probabilistic model. In this preferred embodiment, the observed data d obs is data directly or indirectly related to the movement of fluids in the reservoir. Observed data d obs , by way of example and not limitation, may include: flowing and static pressure at wells, oil, gas and water production and injection rates at wells, production/injection profiles at wells and 4D seismic among others.
[0033] A likelihood function L is defined in step 200 for the reservoir models. Eqns (1), and (2) below represent non-limiting examples of likelihood functions L:
[0000]
L
(
α
_
)
=
k
exp
(
-
1
2
(
d
_
obs
-
d
_
calc
)
T
C
d
-
1
(
d
_
obs
-
d
_
calc
)
)
(
1
)
[0000] or alternatively
[0000]
L
(
α
_
)
=
k
exp
(
-
∑
i
=
1
i
=
n_data
d
i
obs
-
d
i
calc
σ
i
)
(
2
)
[0000] where
L=the likelihood function; k=is a constant of proportionality; {right arrow over (d)} obs =observed data; {right arrow over (d)} calc =calculated data; C d −1 =inverse of covariance matrix of observed data; n_data=number of observed data points; σ i =standard deviation for observation i; and i=index of data points in model parameter space.
[0042] For a more comprehensive list of approaches to define likelihood functions L, see Tarantola.
[0043] A likelihood proxy LP, preferably a “usable” likelihood proxy, for the likelihood function L is constructed in step 300 . A “usable” likelihood proxy is a proxy that provides an approximation to the mathematically exact likelihood function L within a predetermined criterion.
[0044] FIG. 2 is a flowchart describing exemplary steps comprising overall step 300 . A trial likelihood proxy LP is selected in step 310 . This trial likelihood proxy LP is ideally a low computational cost substitute for a computationally intensive model, such as is involved in computing an actual likelihood function L. The trial likelihood proxy LP need not be based on any physical laws. For example, it may be one of multi-dimensional data interpolation algorithms, such as kriging algorithms, which are commonly used in the field of geostatistics. In this exemplary embodiment, the preferred trial likelihood proxy LP for the estimation of the likelihood function L is a multi-dimensional data interpolator. The trial likelihood proxy LP uses, as part of its input, the reservoir model parameters m and produces an estimation of the likelihood function L that otherwise would practically have to be computed using a numerical flow simulator. Other non-limiting examples of trial likelihood proxies LP include other estimators such as, splines, Bezier curves, polynomials, etc.
[0045] A selected trial likelihood proxy LP may also require, as inputs, a secondary set of parameters β that can be used as tuning parameters. An approximation, P, to the likelihood function L, may be estimated as:
[0000] L (α)˜ P=f (α,β, s,v ) (3)
[0000] where
f=trial likelihood proxy LP or the functional or algorithm to perform the estimation of L; α=a vector of reservoir model parameters m characterizing a reservoir model; s=a vector representing the locations in the reservoir model parameter space that has been previously sampled using a numerical flow simulator; v=a vector corresponding to the values of L at the previously sampled locations s; and β=additional input parameters for f.
[0051] For example, if f is a kriging interpolation algorithm, then a variogram is a parameter for f.
[0052] If the full or partial gradients of L, with respect to the model parameters β, ∇L or grad(L), are available, then the definition of the proxy f is adjusted to take advantage of the gradient information, i.e., P=f(α, s, v, ∇β, β).
[0053] The likelihood proxy LP, which is a low computational cost substitute for L, can be constructed to model L directly or indirectly, as in the case of constructing proxies for a function of L, for example log (L); or proxies for d calc which are used as input in the definition of L (Eqns. 1 and 2).
[0054] A proxy quality function index J 1 is defined in step 320 . This proxy quality function index J 1 is used to assess the quality of the output from the trial likelihood proxy LP relative to the output that would otherwise be obtained from a run of the numerical flow simulator. In this exemplary embodiment, a preferred mathematical form of the proxy quality function index J 1 may be expressed as:
[0000] J =(Σ( w i *|L i −P i | p ) 1/p ) (4) where
w i =weighting factor for the sample i; L i =mathematically exact likelihood function for the sample i; P i =estimated likelihood function for the sample i; and p=power (usually 1 or 2).
[0060] A first set of vectors a of reservoir model parameters m are selected in step 330 . The reservoir models are constructed using reservoir model parameters m that are obtained from sampling the model parameter space within feasibility regions. Feasible models, located within the feasibility regions, are considered those which have a probability greater than zero in the a priori probability models. The sample locations are ideally determined using experimental design techniques. In this exemplary embodiment, the most preferred experimental design techniques are those which ensure that there is a good coverage of the sample space, such as using a uniform design sampling algorithm. Consequently, the sample vectors a are preferably more or less equidistantly distributed in the parameter space. Alternatively, sample locations might be determined using the experience of an expert practitioner. As a result of the above process, a geological model and a flow simulation model are obtained for each sample point.
[0061] Numerical flow simulations are run in step 340 on each of the flow simulation models constructed in step 330 to produce calculated data d calc . This calculated data d calc is required to calculate the likelihood function L defined in step 200 .
[0062] A likelihood threshold L thr is selected in step 350 . The value of likelihood threshold L thr is selected in such away that models that result in L less than the threshold L thr are considered very unlikely models. The threshold L thr will be used to guide the construction of the likelihood proxy LP in a step 390 , to be described below.
[0063] Likelihood functions L are computed in step 360 for the vector a of reservoir model parameters m of step 340 by combining the calculated data d calc , d obs , and the probability model for the observed data d obs defined in step 100 . This computation utilizes Eqns. (1) or (2) of step 200 . The results of the calculations are stored in step 365 in a flow simulation database which ideally stores (1) the vectors a of reservoir model parameters m used to create the flow simulation models, (2) the calculated data d calc and (3) the computed likelihood functions L.
[0064] An enhanced likelihood proxy LP is created in step 370 by optimizing the trial likelihood proxy LP utilizing the proxy quality function index J 1 . This step includes searching for a secondary set of parameters β, of step 310 , which results in a better proxy quality function J 1 , of step 320 . That is, the value of J 1 is minimized. In this exemplary embodiment, a preferred method of searching is based on gradients algorithms. Other non-limiting examples of applications might use commonly known optimizers, such as simulated annealing, genetic algorithms, polytopes, random search, trial and error.
[0065] The proxy quality function J 1 may be computed in several ways, depending on the particular type of trial likelihood proxy LP. For example, when using interpolation algorithms, such as kriging, there are numerous ways of calculating the proxy quality function index J 1 . As a first example, the database may contain n different sample points, i.e., 1000 points. A first set of 700 points may be selected to build a trial likelihood proxy LP. Then, the remaining points, i.e., i=300 points, are used to make comparisons such as described in equation (4). In the most preferred embodiment, one point is extracted from the set of 1000 points and a trial likelihood proxy LP is created from the remaining 999 points. The estimation error of this extracted point is then computed for this likelihood proxy LP. This process of removing one point, calculating the proxy for the remaining points, and then calculating the error between that trial likelihood proxy LP and the extracted point is used to create the proxy quality function index J 1 .
[0066] In step 380 , the enhanced likelihood proxy LP of step 370 is evaluated as to whether it meets a predetermined criterion. For example, the predetermined criterion might be checking whether the enhanced likelihood proxy LP is within 10% of the true value which is produced from a simulation run associated with the tested location, i.e. space vector s. If the predetermined criterion is met, then the enhanced proxy is considered to be a “usable” proxy. If the predetermined criterion is not met, then additional samplings are needed to improve the quality of the likelihood proxy LP. In the event a predetermined number of simulations or a time limit is reached without arriving at a “usable” likelihood proxy LP, and if a large number of sets or vector a of reservoir parameters m have been identified that produce reasonable matches to the observed data d obs , then the process is ended. These models a of reservoir parameters m are then used to estimate the range of variability of reservoir parameters and forecasts.
[0067] In step 390 , a new set or vector a of reservoir models is selected to generate new trial likelihood proxy LP candidates. Step 390 is further detailed out in steps 392 - 396 . Referring now to FIG. 3 , in step 392 , a first set of n f reservoir models is selected using the following process. The parameter space is sampled at the n f locations using the enhanced likelihood proxy LP from step 370 . In this process, the number n f of samples used is much greater than 1. This number n f is generally greater than 100, more preferably greater than 10,000, and most preferably will be on the order of a few million samples.
[0068] The process for obtaining the n f samples of locations is made in this example through the application of parallel or sequential sampling techniques such as experimental design, Monte Carlo, and/or deterministic search algorithms for finding locations in the parameter space that result in high values of estimated likelihood P. For example, the sampling technique could be random sampling, simulated annealing, uniform design, and/or gradient based optimization algorithms such as BFGS (Broyden, Fletcher, Golfarb and Shanno) formulation. Those skilled in art will appreciate that there are many other sampling techniques that will work with this invention. For example, see Tarantola and/or Philip E. Gill, Walter Murray, and Margaret H. Wright, Practical Optimization , Academic Press, (1992) for additional of these techniques.
[0069] The sampling may use one or a combination of several sampling and searching techniques. For example, if only one technique were used, then random sampling might be used. Or else, as a combination of techniques, random sampling, uniform design, random walks (such as Metropolis type algorithms) and gradient search algorithms might be used on each of a million sample points of the parameters to obtain the values of P for each of the sample points.
[0070] For each of the n f points selected, an estimated value of likelihood P is computed in step 394 .
[0071] It is generally not computationally practical to run numerical flow simulations on all n f sample points. Therefore, in step 396 a proper subset of n b sample points is preferably selected from the n f sample points. The size of this proper subset n b is related to the available computational power to run numerical flow simulations. For example, assume n f =1,000,000 and the proper subset n b =100. Ideally, the 100 sample points are chosen to equidistantly sample the parameter space. Further, the region in the parameter space to be improved is the region or regions that provide high values of P. However, some samples are required in regions of the parameter space that are highly uncertain. This sampling is performed through a combination of “exploration” and “refining.” “Exploration” refers to the sampling of regions of the parameter space with high uncertainty. “Refining” refers to the process of improving the quality of the proxy in regions that have already been identified as having high values of P. In the refining step, the selection is made such that the value of P is higher than the threshold value L thr determined in step 350 . From this proper subset n b . 100 sample points are selected which are generally equidistantly spaced, apart with respect to the previously locations that were sampled and used in flow simulations in step 340 and between the n b points. These n b points are used to create reservoir models to be processed in flow simulation in step 340 .
[0072] FIG. 4 depicts the evolution of likelihood proxy LP during the process of step 300 in constructing a usable likelihood. For the sake of simplicity a graph of likelihood L versus a particular reservoir parameter m is shown. The likelihood threshold L thr is shown by a dotted line. The true likelihood function L is shown by a solid line. This true likelihood function L is equivalent to sampling with an infinite number of numerical flow simulations. The purpose of step 300 is to find a likelihood proxy (or substitute) that provides a good estimation of the true likelihood L at a significantly lower computational cost. A line-dot curve is used to represent the computed value P (the estimated value of L using a likelihood proxy LP) for the case of a small number of samples, at the earlier stages of process 300 . This likelihood proxy LP does not generally provide a good approximation to L, and thus it is not generally usable proxy. A line-dot-dot curve represents a usable proxy LP, which provides a good approximation to L. This usable proxy LP is obtained after applying the process of taking addition samples during the refining and exploration stages in process 300 .
[0073] A usable forecast proxy FP is constructed in step 400 . Referring now to FIG. 5 , a trial forecast proxy FP is selected in step 410 . A proxy quality function index J 2 is defined in step 420 . The functional form for J 2 is similar to J 1 in Eqn. (4), but using forecasts instead of likelihood L. In step 430 , reservoir model parameters are selected which were stored in step 365 and which have a likelihood L greater than a predetermined threshold, i.e, L thr . In step 440 , reservoir simulations are run on the models selected in step 430 to create output forecast data d out . In step 450 , the trial forecast proxy FP of step 410 is optimized using the tuning parameters β to produce an optimized quality proxy index J 2 . In step 460 , a determination is made as to whether the enhanced forecast proxy FP meets a predetermined criterion of usability. If the criterion is not met, then a new trial forecast proxy FP is selected in step 410 and steps 450 - 460 are repeated. If after many trials no useable forecast proxy FP is found, then additional simulations are needed. However, if the criterion is met, then the enhanced forecast proxy FP is deemed usable.
[0074] At this point, two usable proxies have been created. The LP proxy for the likelihood function LP has been created in step 300 and the forecast proxy FP has been created in step 400 .
[0075] Reservoir model parameters are sampled in step 500 with Monte Carlo techniques utilizing the usable proxy LP for the likelihood function L, the forecast proxy FP, and utilizing the probability models to determine a set of retained models and their associated forecasts. In a preferred embodiment, the model parameter space is sampled using the well known Metropolis type algorithms that perform random walks in the reservoir model parameter space. Again, Tarantola can be consulted for a more detailed explanation.
[0076] Referring now to FIG. 6 , a reservoir model is proposed in step 510 from a random walk process that ensures the a priori probability models defined in step 100 . In step 520 , P, the estimated value for the likelihood function L, is computed using the usable likelihood proxy LP. The proposed model is tested based on an accept/reject basis in step 530 . If the estimated likelihood P for the proposed model is higher or equal than the estimated likelihood P of the previously accepted model, then the proposed model is accepted. If that is not the case, that is the estimated likelihood P for the proposed model is lower than the estimated likelihood P of the previously accepted model, then the proposed model is accepted randomly with a probability P proposed /P last — accepted .
[0077] If the reservoir model parameters in is rejected, then this reservoir model is ignored and another reservoir model will again be proposed in step 510 . If the reservoir model parameters are accepted, then an estimated forecast associated with the reservoir model parameters is computed in step 540 using the forecast proxy FP. The reservoir model parameters α and the associated forecast are stored for further use in step 550 .
[0078] In step 560 , a check is made to see if enough retained models have been accepted. If not, then another set a reservoir model parameter m is proposed in step 510 . When sufficient retained models and their associated forecast have been determined and stored, statistics are computed in step 610 . A first set of statistics can be generated for the sets α of reservoir model parameters m. This is commonly referred to as a “posterior probability” for the reservoir model parameters. A second set of statistics can be prepared for the forecast.
[0079] Ideally, these statistics are then displayed in step 620 in the form of a histogram, probability density function, probability cumulative density function (CDF), tables, etc.
[0080] Alternatively, by way of example and not limitation, step 500 could also be accomplished by direct application of Bayes Theorem (probability theory) using a large number of random sample points. See Eqn. (5) below:
[0000]
p
(
α
_
d
obs
)
=
p
(
α
_
)
p
(
d
obs
α
_
)
p
(
d
obs
)
=
k
1
p
(
α
_
)
L
(
α
_
)
p
(
d
obs
)
≅
k
1
p
(
α
_
)
P
(
α
_
)
p
(
d
obs
)
=
k
2
p
(
α
_
)
P
(
α
_
)
(
5
)
[0000] where k 1 and k 2 are proportionality constants, p(α|d obs ) is the “posterior” probability of the reservoir model parameters (probability after adding the d obs information), p(α) is the “a priori” probability of the reservoir model parameters (probability before adding the d obs information); and P(a) is approximation to the Likelihood L computed using the usable proxy.
[0081] While in the foregoing specification this invention has been described in relation to certain preferred embodiments thereof, and many details have been set forth for purpose of illustration, it will be apparent to those skilled in the art that the invention is susceptible to alteration and that certain other details described herein can vary considerably without departing from the basic principles of the invention. | A method, system and program storage device for history matching and forecasting of subterranean reservoirs is provided. Reservoir parameters and probability models associated with a reservoir model are defined. A likelihood function associated with observed data is also defined. A usable likelihood proxy for the likelihood function is constructed. Reservoir model parameters are sampled utilizing the usable proxy for the likelihood function and utilizing the probability models to determine a set of retained models. Forecasts are estimated for the retained models using a forecast proxy. Finally, computations are made on the parameters and forecasts associated with the retained models to obtain at least one of probability density functions, cumulative density functions and histograms for the reservoir model parameters and forecasts. The system carries out the above method and the program storage device carries instructions for carrying out the method. | 4 |
CROSS REFERENCE TO RELATED APPLICATION
This application is a division of U.S. patent application Ser. No. 11/405,149 filed on Apr. 17, 2006.
BACKGROUND AND SUMMARY OF THE INVENTION
Wristbands formed by die cuts made in multi-ply forms so as to be processible by printers and especially laser printers are known in the art. One of the inventors herein is an inventor of a number of different wristband forms as shown in his prior U.S. Pat. Nos. 5,933,993, 6,000,160, 6,067,739, 6,438,881, 6,510,634, 6,748,687, 7,017,293 and 7,017,294, the disclosures of which are incorporated herein by reference. Each of the wristbands disclosed in these prior patents are self laminating, meaning that they contain a laminate layer or ply which, when the wristband is separated from its carrier, may be folded over to encapsulate an imaging area typically defined by a die cut in a face stock ply. These imaging areas are desirably sized to extend along a substantial length thereof so as to provide “real estate” for receiving printed data. This printed data may include the patient's name, the attending doctor's name, a patient ID number, admission date, medical information such as special precaution concerns such as allergic reactions, etc., and even more recently a bar code which is swiped numerous times a day. Some are putting photo images of the patient in the imaging area, taking advantage of the recent advances in digital photographic technology. As a result of the desire to put ever increasing amounts of data and even images on the imaging area, the size including especially the length of the imaging area is desirably long.
Although this desire to provide maximum “real estate” for imaging leads to longer imaging areas, the anatomical limits of the patient's wrist around which the wristband wraps create some practical limitations to this length, even for adult sized wristbands. As the imaging area is typically made from a face stock or other print receptive material such as bond paper, it typically exhibits a relative stiffness when compared with the laminate backing ply. This relative stiffness helps the imaging area to lie flat against the wrist so as to enhance the readability of the data imaged onto it. However, as the imaging area is typically a single length of regularly sized face stock, formed into the shape of a rectangle with rounded corners, the imaging area can have a tendency to bow, or assume an arcuate shape, to more closely fit about the patient's wrist especially if the wristband is tightened close to the wrist. While this does present some inconvenience for a nurse or other medical professional seeking to read the information contained in the imaging area, it is more of a problem now that bar codes have come into common usage. That's because bar code readers are better able to accurately read when the bar code is lying flat and not on a curved surface.
In order to further improve on the good and valuable inventions previously developed, patented, and for which great commercial success has been achieved, the inventors herein have succeeded in designing a self laminating wristband along the lines of several of those disclosed and claimed in the patents mentioned above, except that the single imaging area has been formed, preferably, into two or more separated imaging areas. Between each pair of imaging areas, there is created a natural hinge or fold point therebetween which permits the wristband to bend around the wearer's wrist so that each imaging area lies flat against a portion of the wrist instead of “bowing” or even perhaps wrinkling or crinkling at a point of stress determined at random as the wristband is secured and tightened about the wrist. The space between the imaging areas is bridged by two layers of laminate, which necessarily is of a thinner dimension than that formed in the imaging areas as there is no face stock in the intervening space. The types of imaging areas preferably include a main area of larger length and one or more “side car” or auxiliary imaging areas spaced from the main area and arranged along the longitudinal axis of the wristband, or crossways to the wearer's wrist. Alternatively, multiple equally sized imaging areas may be provided. If two smaller auxiliary imaging areas are provided, they preferably are located on either side of the main imaging area.
This side car auxiliary imaging area is preferably a square, although it could be formed in any convenient shape as desired and to suit the individual application. For example, the auxiliary imaging area may be formed in the shape of a circle, or it may be intended to be merely decorative, or it may be intended to receive a trademark or logo or other indicia for identifying an organization or even the individual. This auxiliary imaging area may also be imprinted with any data, as desired or to suit individual needs. For example, the imaging area may be imprinted with a photo of the patient taken by a digital camera upon admission. Or the bar code identifying the patient may be imprinted there. Another example would be for “special precautions” flags or markers to be placed on the auxiliary area. Yet another use for this auxiliary imaging area may be to separate critical patient care data from administrative data. For example, legends such as “Do Not Resuscitate”, blood type information, or other important data may be separated from other administrative and identification data to guide the health care provider in the event of an emergency or the like. In other words, this area could be designated as a “look first” zone, and highlighted by the use of color to catch the nurse's eye.
To further implement this special precautions application, printed lines may define target areas of the face stock for adhering matching laminate portions peeled off the laminate ply of the form in which the wristband is carried. In one such example shown in greater detail below, three ellipses are defined by printed lines in the auxiliary imaging area which may be individually used. On the back of the laminate ply are a series of matching ellipses of different color with each color providing an indication of a different special caution condition. Although special precautions indicators are preferably applied prior to laminating the wristband, with this arrangement a special precautions indicator may be added after the wristband has been applied to the patient's wrist which eliminates the need to “re-band” the patient with a new wristband in those instances. There are other uses for the auxiliary imaging area, limited only by the imagination of the designer.
The wristband invention disclosed herein may be provided in a “sheetlet” or envelope sized page containing the wristband and perhaps an extender which, as is explained in the inventor's prior patents, may be used to extend the length of the wristband for those patients having particularly large wrists. Also disclosed herein is the wristband as provided in a “combo” or larger sized page combined with a matrix of a plurality of self adhering labels. Yet another embodiment is a page having four wristbands, two of adult size and two of infant size such as might be used in a maternity or pediatric ward of a medical facility. In these embodiments, the wristband is preferably defined by a plurality of die cuts formed in a two ply business form comprised of a page. The top ply is a face stock or imaging layer, the bottom ply is a laminate layer, and a layer of patterned adhesive joins the two layers. The die cuts are arranged to permit the separation of the unassembled wristband from the page in an assembly, with the laminate ply including a clamshell portion for folding over and encapsulating both imaging areas. In one embodiment shown, a pair of integrally formed, adhesive coated tabs at opposite ends of the wristband are used to attach the wristband to the wearer's wrist, as shown in the inventor's prior patents. In another embodiment, the wristband further includes a cinch attachment, again as is disclosed in several of the inventor's prior patents, generally comprising a strap or tail portion extending to one side of the imaging areas and a slot portion on the opposite side of the imaging areas and through which the tail portion is inserted for securing the wristband. Preferably, a patch of adhesive at the tip of the tail portion is then used to adhere it back onto itself after passing through the slot and finish the attachment of the wristband. The cinch is operably formed in the laminate ply alone.
While the principal advantages and features of the invention have been briefly explained above, a more thorough understanding of the invention may be attained through referring to the drawings and reading the description of the preferred embodiment below.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a plan view of a sheetlet sized page detailing the die cuts in a face stock ply defining the two imaging areas with the auxiliary imaging area having three printed outlines for identifying special precautions marker target areas and a printed line defining the outline of the entire wristband,
FIG. 2 is a plan view of a sheetlet similar to that of FIG. 1 except with the auxiliary imaging area having no printed lines defining special precautions target areas and instead adapted to receive data imprinted thereon,
FIG. 3 is a plan view of a sheetlet similar to that of FIG. 1 except that a pair of auxiliary imaging areas are defined by die cuts, with one being substantially square and the second being substantially circular in shape,
FIG. 4 is a plan view of the back or laminate ply of the sheetlet shown in FIG. 1 with die cuts defining the laminate portion including the cinch tail and slot, special precautions markers, and a security seal,
FIG. 5 is a plan view of a full size page, either 8½ by 11 inches or A4 size or any other convenient size, with the wristband of FIG. 1 combined with a matrix of a plurality of self adhering labels,
FIG. 6 is a plan view of a full size page, either 8½ by 11 inches or A4 size or any other convenient size, with the wristband of FIG. 2 combined with a matrix of a plurality of self adhering labels,
FIG. 7 is a plan view of a full size page, either 8½ by 11 inches or A4 size or any other convenient size, with four wristbands of FIG. 1 provided in adult length and infant length,
FIG. 8 is a plan view of a full size page business form with both a wristband and labels, with the wristband being of a full length laminate clamshell and integral tab fastener embodiment, and with a pair of auxiliary imaging areas provided one on either side of a main imaging area,
FIG. 9 is a plan view of a full size page business form with both a wristband and labels, with the wristband being of a full length laminate clamshell and integral tab fastener embodiment, and having a main imaging area and an auxiliary imaging area to one side,
FIG. 10 is a plan view of a full size page business form with both a wristband and labels, with the wristband being of a full length laminate clamshell and integral tab fastener embodiment, and having a main imaging area and a pair of circular auxiliary imaging areas one on each side of the main imaging area,
FIG. 11 is a plan view of the back or laminate ply of the full page size sheet of FIGS. 8-10 and illustrate the full length clamshell laminating portion and, as an example, a printed line showing three imaging portions as might be die cut into the face stock ply, and
FIG. 12 is a perspective view of the wristband of FIG. 1 applied to a patient's wrist.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The wristband 100 of the present invention is shown as a first embodiment in FIGS. 1 , 4 as defined by a plurality of die cuts in the face ply layer 102 of FIG. 1 and the laminate ply layer 104 of FIG. 4 , both of which comprise a sheetlet sized page 105 . As shown in FIG. 1 , a first die cut 106 defines a first imaging area 108 , a second die cut 110 defines a second side car or auxiliary imaging area 112 and a third die cut 114 defines a removable tab 116 covering of a layer of adhesive for use in securing the wristband as will be explained below. Also as shown in FIG. 1 , three separate print lines 118 define three separate ellipse target areas 120 for adhering the special precautions markers described below. These special precautions markers are preferably of different color to indicate a different condition, such as allergies, fall risk, do not resuscitate, etc. Also shown in FIG. 1 is a die cut 122 which defines a removable tab 124 covering of a layer of adhesive for use in securing the extender as is explained in the inventor's prior patents. Upon removal of the wristband 100 from the page 105 , the die cuts all separate allowing their defined face ply portions to separate and become part of the separated wristband.
The laminate ply layer 104 as shown in FIG. 4 also has a plurality of die cuts defining the laminating portion 128 of the wristband 100 , as will now be explained. A first die cut 126 surrounds and defines the entirety of the laminating portion 128 of wristband 100 . This laminating portion is shown as being preferably in a clamshell configuration extending the length sufficient to cover both of the imaging areas. Alternatively, the laminating portion could be shortened to cover only one of the imaging areas, or depending on how many imaging areas are used, less than all of them. Second and third die cuts 130 , 132 define slots 134 which along with the tail portion 136 comprise the cinch attachment for the wristband 100 . Slots 134 are firmly adhered to the face ply layer 102 so that upon separation of the wristband from the sheetlet 105 , they remain adhered thereto thereby creating holes in the laminating portion 128 . Also indicated by an outline 138 is a clear area 140 of the laminating portion 128 under which is a layer of release so that upon separation of the wristband and folding over of the bottom half of the laminating portion 128 the clear area 140 is not obscured by any adhesive as it overlies the imaging area 108 . Although not shown, a second clear area may be formed to overlie the second imaging area 112 . Should printed data be placed on the second imaging area 112 , this second clear area would be desired. For the embodiments shown in FIGS. 1 and 3 , with special precautions areas or ellipses 120 , it is generally desired to coat this area with adhesive to help hold the laminating portion 128 together and in place over the special precautions markers. Additional die cuts 142 define the special precautions ellipses 144 , die cut 146 defines a security seal 148 , and die cuts 150 define additional markers 152 which may comprise “window pane” highlighters for placement on either imaging area preferably before folding over the laminating portion 128 to help highlight selected printed data. The security seal 148 may be applied over the tail portion of the cinch attachment to not only further secure it but also provide an indication of tampering should a patient try to remove and replace it, such as in an attempt to switch wristbands with another patient. Another die cut 154 defines the extender 156 for extending the length of the wristband 100 through attachment at the end of tail portion 136 . A layer of patterned adhesive, not shown, joins the two plies 102 , 104 as appropriate and as would be apparent to those or ordinary skill in the art to allow ready separation of the wristband 100 as an assembly of the face ply portions defined by die cuts and the laminating portion 128 and assembly through folding over the two halves of the laminating portion 128 to enclose the imaging areas 108 , 112 .
As depicted in FIG. 2 , the second imaging area 158 may be configured simply as another area for receiving printed information as the sheetlet page 105 is processed through a laser printer prior to separation of the wristband 100 therefrom. Any desired data may be imaged on the second imaging area 158 including for example a photographic image of the wearer, a bar code identifying the wearer, a trademark or logo, etc. Otherwise, the embodiment shown in FIG. 2 is the same as that depicted in FIG. 1 .
As depicted in FIG. 3 , a pair of second imaging areas 159 , one of which may be formed in the shape of a circle or other decorative design or shape may be provided, with one on either side of the main imaging area 108 . In this embodiment wristband, with the shortened clamshell laminating portion and cinch attachment, use of two second imaging areas 159 necessitates a smaller main imaging area 108 in order to yet provide a sufficient length tail portion 136 to properly attach the wristband to a wearer. Alternatively, a longer length imaging area may be provided and reliance made on the extender to attach the wristband.
As depicted in FIGS. 5 and 6 , either embodiment of the wristband 100 depicted in FIG. 1 , 2 , or 3 may be configured as a “combo” form with a matrix of a plurality of self adhering labels 160 . In these embodiments, the page 162 is sized appropriately at 8½ inches by 11 inches, A4, or any other convenient size for processing through a printer which is preferably a laser printer. For illustration, lines are depicted in FIGS. 5 and 6 showing the outline of the laminating portion of the wristband which is die cut into the laminating ply which backs this top or face stock ply.
Yet another embodiment of the present invention is shown in FIG. 7 and comprises two adult sized wristbands 100 along with two infant sized wristbands 164 . The arrangement of the wristbands on the page 166 , and the relative sizing of the wristbands, may be adjusted as desired to suit any particular application.
Still another embodiment of the present invention is shown in FIG. 8 and comprises a full size page with a wristband of the type having a full length laminating portion with two integrally formed, adhesive coated tabs at its ends for securing the wristband. With this embodiment, the face ply extends for a greater length along the wristband and there is thus more length of imaging area with which to work with. In this embodiment, a main first imaging area 168 is flanked on either side by a second auxiliary imaging area 170 such that a hinge 172 is formed in two places of the laminate ply along the length of the wristband. Still other alternative versions of this embodiment are depicted in FIGS. 9 , 10 which include a somewhat shorter main imaging area 174 and a single second imaging area 176 of rectangular shape to one side thereof; and a main imaging area 178 flanked on either side by a circularly shaped second imaging area 180 .
The full length, clamshell laminating portion 181 as would be typically used with the face stock ply depicted in FIGS. 8-10 is shown in FIG. 11 . As shown therein, the laminating portion extends substantially the full length of the wristband and has a pair of integrally formed, adhesive coated tabs 183 at its ends for attaching the wristband to a wearer. As an example of the use that could be made of this increased length of imaging area in this embodiment, three imaging areas are shown with a hinge provided between each pair of imaging areas. Alternatively, the laminating portion 181 could be sized to extend less than the full length of the wristband and cover fewer than all of the imaging areas.
Use of the wristband 100 is shown in FIG. 12 . As depicted therein, the wristband has been separated from its respective carrier page, assembled through application of several special precautions markers before laminating the imaging areas, and then secured to the wearer's wrist with the cinch attachment. When so applied, the gap separating the second imaging area from the first imaging area along the length of the wristband, and between any two imaging areas or group of imaging areas so arranged, has a natural tendency to fold in the fashion of a hinge, which for clarity has been marked with a line and numbered as 182 in the drawing figure. However, it is not necessary, or preferably provided, that a line or crease or other weakness be created in this gap or intervening space, although one could be provided. With this configuration however, the wristband has a tendency to follow the contour of the wearer's wrist and bend which has the desired effect of allowing the imaging areas to become flatter in orientation than if no such separation were provided between the two imaging areas. This flatter orientation provides for better readability, and especially for reading bar codes. It also provides a natural placement and fit for the wristband to the wearer's wrist as the hinge point naturally orients at a location to accommodate the contour of the wrist. Should more imaging areas be provided along the wristband length, they are preferably positioned to provide a hinge at the location of the wristband where it curves around the wrist, although this is not necessary. It is also noted by the inventors that groupings of imaging areas could be provided, or offset imaging areas, overlapping imaging areas, imaging areas in mixed patterns such as in a diamond shaped or diagonally offset pattern, etc. all of which could contribute to an increased flexibility of the wristband even should a distinct gap not be provided to delineate a hinge point.
The present invention has been disclosed and described in several embodiments. It would be understood by those of skill in the art that various changes and modifications could be made without departing from the spirit and scope of the invention. For example, the imaging areas are depicted as having a particular shape although other shapes could be used. Also, two or three imaging areas are shown but more could be provided. Furthermore, the arrangement of the imaging areas may be changed. The relative size of the imaging areas could be varied. For example, the imaging area are all shown to be of approximately the same width, which is substantially the full width of the wristband. However, different height imaging areas could be provided, with some imaging areas being stacked one above the other, and the hinge feature would only be active between those imaging areas arranged along the length of the wristband. The self laminating clamshell design of various size as disclosed in the inventor's earlier patents has been incorporated into the present design although separated laminating portions could be used and assembled as would be apparent to those of skill in the art. The ellipses arranged on the second imaging area are merely design choices and different shapes or colors for the special precaution markers could be used. The choice of materials is optional and would be those well known to those of skill in the art. Yet other changes could be contemplated, and those as well are to be considered within the scope of the invention which is limited to the scope of the claims and their equivalents. | A self laminating wristband separable from a multi-ply page form has a plurality of separated imaging areas, with one larger imaging area for receiving printed data corresponding to the wearer such as his name, i.d. number, etc., with one or more second imaging areas adapted to receive either printed information or markers which may be adhered thereto. The separated imaging areas are aligned along the length of the wristband so that the gap between them acts as a natural hinge point which allows the imaging areas to lie flatter against the wearer's wrist. | 8 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to antitumor anthracycline antibiotics and more particularly, to N-acyl derivatives of the known antitumor antibiotic carminomycin.
2. The Prior Art
It is well known that carminomycin is a natural anthracycline antibiotic which displays antitumor activity in humans and animals (G. F. Gause, M. G. Brazhnikova and V. A. Shorin, Cancer Chemother. Rep., Part 1, 58, 255 (1974)). Unfortunately, the therapeutic usefulness of carminomycin is severely restricted because of its high toxicity. Moreover, carminomycin can be obtained in only limited amounts from natural sources and no practical syntheses for carminomycin are known; although a total synthesis of the aglycone has been reported in the literature (Kende et al, J. Am. Chem. Soc. 98, 1967 (1976)).
SUMMARY OF THE INVENTION
The present invention relates to carminomycin derivatives and to a synthetic process for the manufacture of carminomycin and its derivatives which are provided by the invention.
The present invention provides, in one aspect thereof, N-acyl derivatives of carminomycin of the formula I: ##STR1## wherein R is an acyl group selected from the group consisting of acetyl, mono, di and trichloroacetyl, trifluoroacetyl, benzoyl and substituted benzoyl. Presently, the most preferred such compound is the trifluoroacetyl derivative.
According to the invention, the compounds of formula I [wherein R, in addition to being as defined above, may also be hydrogen--in which case, the compound is the known antibiotic carminomycin], are prepared from daunomycinone (II), according to scheme I (below), with particular emphasis on the new N-acyl derivatives of carminomycin. As shown in scheme I, daunomycinone (II) is demethylated with a Lewis acid such as aluminum trichloride, or tribromide, to form the aglycone of carminomycin (III). The latter is then condensed with a 2,3,6-trideoxy-3-acylamido-4-O-acyl-α-L-lyxopyranosyl chloride to yield compound (IV), wherein the acyl groups are R, as defined above.
A mild hydrolysis of (IV) in methanol containing triethylamine leads to the N-acyl derivatives of carminomycin (I; R=the acyl groups as specified above, preferably, trifluoroacetyl). When R is trifluoroacetyl, the compound (I) in turn can be transformed into carminomycin itself (I; R=H) by treatment with an aqueous alkaline base. ##STR2##
In yet another aspect, the invention provides a method of treating certain mammalian tumors using the new N-acyl derivatives of carminomycin. These new N-acyl derivatives of carminomycin are endowed with antitumor activity in mammals and are much less toxic than the parent compound, carminomycin.
In particular, N-trifluoroacetylcarminomycin, because of its very low toxicity, can be administered at very high doses which results in a more effective antitumor activity than carminomycin itself.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The following examples are given to more clearly describe the invention. Unless otherwise specified, all parts given are by weight.
EXAMPLE 1
4-Demethoxy-4-hydroxydaunomycinone (III)
To a refluxed solution of 10 g. of daunomycinone (II) in 1 liter of dichloromethane, 30 g. of aluminum trichloride were added over a two hour period with stirring. After an additional 4 hour period, the reaction mixture was cooled and poured into ice water containing 150 g. of oxalic acid. The organic layer was separated, washed with water and concentrated in vacuo to yield 6 g. of crystalline 4-demethoxy-4-hydroxy-daunomycinone (III), which were collected by filtration.
EXAMPLE 2
N-trifluoroacetylcarminomycin (I; R=CF 3 CO--)
To a solution of 1 g. of 4-demethoxy-4-hydroxydaunomycinone (III) and 0.850 g. of 2,3,6-trideoxy-3-trifluoroacetamido-4-O-trifluoroacetyl-α-L-lyxopyranosyl chloride in a 1:1 mixture of dimethyl formamide and dichloromethane, a solution of 0.570 g. of silver trifluoromethanesulfonate in 15 ml. of anhydrous diethyl ether was added dropwise at room temperature. After 1 hour of stirring, the reaction mixture was diluted with dichloromethane, washed with an aqueous solution of NaHCO 3 and finally with water. The solvent was removed in vacuo and the residue taken up in chloroform. The insoluble starting material was removed by filtration, and the filtrate was evaporated to a residue which was then dissolved in methanol containing a trace of triethylamine. The resulting solution was left to stand for 2 hours at room temperature. Removal of the solvent in vacuo and purification of the residue by column chromatography (silica gel; chloroform/acetone 95:5, v/v) afforded 0.370 g. of N-trifluoroacetyl carminomycin I; R=CF 3 CO--).
EXAMPLE 3
Carminomycin hydrochloride (I; R=H)
0.5 grams of N-trifluoroacetyl carminomycin (I; R=CF 3 CO--) was dissolved in 0.15 N NaOH and left standing for 2 hours at room temperature. After acidification with oxalic acid and neutralization with aqueous NaHCO 3 , the free base with extracted with dichloromethane which was washed with water. The solvent was removed in vacuo and the resulting residue was dissolved in dry dichloromethane and treated with 1 equivalent of HCl in methanol. The solution was then concentrated in vacuo and diethyl ether was added to precipitate 0.300 g. of carminomycin hydrochloride (I; R=H), which was found to be identical to an authentic sample.
Biological Activity
The activity of N-trifluoroacetyl carminomycin (I; R=CF 3 CO--) on P 388 lymphocytic leukemia in CDF 1 male mice (tumor inoculum 10 6 cells i.p.) in comparison with daunorubicin, doxorubicin and carminomycin was determined. Treatment i.p. was effected on days 5, 9 and 13 after inoculation.sup.(a)
Table 1______________________________________ Dose mg./kg. T/C.sup.(b)______________________________________Daunorubicin 8 126 4 115 2 122 1 117 0.5 108Doxorubicin 8 185 4 141 2 126 1 122 0.5 106N-trifluoroacetyl- 25 123carminomycin 12.5 104 6.25 106 3.1 106 1.56 98Carminomycin 25 0 12.5 91 6.25 0 3.13 129 1.56 130______________________________________ .sup.(a) Data obtained under auspices of National Cancer Institute. .sup.(b) Median survival time expressed as percent of untreated controls.
The results of another series of experiments, under the same conditions as in Table 1, are reported in Table 2.
Table 2______________________________________ Dose mg./kg. T/C.sup.(b)______________________________________Daunorubicin 32 96 16 123 8 132 4 126 2 123Doxorubicin 16 92 8 191 4 189 2 145 1 110N-trifluoroacetyl- 200 215carminomycin 100 118 50 145 25 118 12.5 96______________________________________
Variations and modifications can, of course, be made without departing from the spirit and scope of the invention. | N-acyl derivatives of the known antitumor antibiotic carminomycin, particularly N-trifluoroacetyl carminomycin, have a much lower toxicity than carminomycin. | 2 |
BACKGROUND OF THE INVENTION
This invention relates to pulsed-transmission, single-frequency echo ranging systems, and more particularly to the array used to form the received acoustic beam in very high resolution side-scanning sonars.
The principal objective of this invention is to reduce the level of grating (side)-lobes caused by spatially undersampled hydrophone arrays.
A further objective is to increase the quality of sonic images that are produced by an array having a given number of staves.
A third objective is to reduce the number of array staves needed to produce an image of given quality.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a graphic showing of array radiation patterns.
FIG. 2 is a graphic showing of array beam and stave radiation.
FIG. 3 is a representation of beam geometry from which time delays can be calculated.
FIG. 4 is a showing of stave pattern nulls and array factor grating lobes.
FIG. 5 is a graphic showing of the array response of a focussed line array showing large grating lobes.
FIG. 6 is a showing of a fixed stave angle variable focal length linear array.
FIG. 7 is a showing of a fixed stave angle, variable focal length circular array.
FIG. 8 is a graphic showing of the location of space factor grating lobes and stave nulls provided by the invention.
FIG. 9 is a graphic showing of the location of space factor grating lobes and stave nulls from a conventional line array.
FIG. 10 is graphic showing of the array response provided by the invention with fixed stave angles and variable focal length.
FIG. 11 is a graphic showing of grating lobe suppression versus focal range.
DETAILED DESCRIPTION OF THE INVENTION
Nearly all sonars having very high resolution beams (beam widths less than 0.5 degrees), operate in the near field (Fresnel) region, and must be focused to produce useful beam patterns. This is most commonly accomplished by constructing a linear array of discrete hydrophone staves so that electronic time delays can be applied to the stave outputs. The individual delays are selected in such a way that the curvature of the arriving spherical wavefront is removed. In contrast to a physically curved array, electronic focusing allows continual refocusing at the appropriate range as the transmitted sound travels through the water. Additional advantages of a sampled array include the ability to (1) amplitude shade the array for increased side lobe rejection, (2) steer the beam, (3) form multiple beams with a single array and (4) change the effective length of the array as the sound travels to maintain a constant azimuthal resolution at all ranges.
Ideally, the staves should be spaced at intervals of not more than one-half wavelength so that spatial aliasing will not occur. This is analogous to the Nyguist sampling theorem in discrete time domain analysis, which requires the sampling frequency to be at least twice the highest signal frequency. For high resolution arrays this would typically necessitate several hundred staves; each with its own preamplifier, filter, time-varied gain stage, and possibly a heterodyne stage. In practice, therefore, arrays are usually undersampled deliberately for economies of cost, size, and power consumption.
The far field radiation pattern, which is also known as the array factor or space factor, of a linear array of n isotropic hydrophones uniformly spaced at intervals d is given by ##EQU1## λ=wavelength.
The radiation pattern of an array element of length D is given by ##EQU2##
By the well known product theorem, the far field radiation pattern of an array of equispaced staves is given by the product of equation (1) and equation (2), and in particular, when the array is completely filled, i.e., when d=D, the beam pattern is ##EQU3##
An example is shown in FIG. 1 where the solid curve 2 is the space factor of an array having 10 dimensionless hydrophones uniformly spaced at 40 wavelength intervals, and the dashed curve 4 is the pattern of a 40 wavelength stave. The major response lobes, 6 and 8, located at plus and minus 1.4 degrees are referred to as grating, side or ambiguous response lobes.
FIG. 2 shows the resulting array pattern in the solid curve 10 with the stave pattern (dashed curve) 12 repeated for reference. Grating lobes are absent. Thus we have an illustration of a case where an array can be successfully undersampled by a factor of 80 to 1. In this special case, the stave pattern may be thought of as the spatial equivalent of an anti-aliasing filter perfectly designed to suppress the ambiguous lobes of the space factor.
The more steering, focusing, or shading (or a combination of these) applied, the greater the level of the grating lobes. The grating lobe locations are a function of the stave spacing and, for an unsteered array, are given by ##EQU4## and θ g is the angle relative to the main response axis, or broadside to the array.
When operating in the near-field region of the array (i.e., distances less than ##EQU5## beam patterns are extremely ill-behaved, and are not useful for producing sonar images. However, by focusing the array, radiation patterns near the focal region become substantially similar to ideal far-field patterns. Because the focal region is typically quite short, it is necessary to refocus frequently as the sonic pulse travels out in range. This can be accomplished conveniently by electronic means, as is usually done in high resolution sonars.
The present invention is specifically concerned with reduction of grating lobes caused by focusing. Electronic focusing is normally achieved by introducing time delays into the stave outputs to compensate for the curvature of the wavefront. The delays are calculated from the geometry shown at 14 in FIG. 3 as ##EQU6##
It will be evident to those skilled in the art that, for a narrow bandwidth sonar, phase shifts given by
φ.sub.i =2πf.sub.0 T.sub.i (6)
where
f 0 =sonar operating frequency can be conveniently substituted for time delays if advantageous to the implementation.
When the array has been thus focused, the space factor grating lobe maxima will fall on lines originating at the array center and inclined at angles θ g given by equation 4. If the stave length D is chosen equal to the stave spacing d, then at very large distances from the array, the stave pattern nulls, occurring at angles ##EQU7## f 0 =sonar operating frequency will all coincide with the space factor grating lobes and cancel them. However, at short ranges, even though all the stave pattern nulls occur at the same angle, they do not originate at the same point. They originate at the stave center of each stave, and therefore do not coincide. Hence they fail to cancel the space factor grating lobes. This is illustrated in FIG. 4 at 16. Only the first array factor grating lobes (i=±1) and the first nulls (i=±1) of the two end stave patterns are shown for clarity.
A typical example of the resulting array beam pattern illustrates the undesirable grating lobes. In FIG. 5, the array response of a hypothetical 10 stave array with 40 wavelength stave length and spacing and focused at 25 meters is shown at 18. The array is shaded with a Dolph-Chebyshev amplitude window. The resulting array grating lobes at 1.4 degrees, 20 and 22, are only 10 dB below the main lobe response 24.
The present invention reduces the grating lobes significantly by forcing all the stave nulls to coincide with the space factor grating lobe at a particular range R SF . This is accomplished by mechanically tilting each stave at a fixed angle relative to broadside of ##EQU8## This is illustrated in FIG. 6 at 26 in somewhat exaggerated form. It will be evident to those skilled in the art that a similar result can be obtained from the circular construction shown at 28 in FIG. 7 if the surface curvature is taken into account when selecting the time delays needed for variable range focusing. The latter arrangement may be more convenient for some applications. This design may be considered a fixed stave angle, variable focal-length array.
The resulting coincidence of stave nulls and space factor grating lobes is illustrated at 30 in FIG. 8 where 25 meters was chosen for R SF . By contrast to FIG. 9, in which is shown at 32 for a conventional array (untilted staves), a superior coincidence of nulls with grating lobes is maintained over nearly all the area of interest.
The resulting radiation pattern of the array is shown at 34 in FIG. 10 at a range of 25 meters. The remaining grating lobes are due entirely to the discrete shading function and the portion due to focusing is completely removed. This pattern is essentially identical to that of an unfocused array at infinite range. This pattern should be compared to that shown in FIG. 5 where the grating lobe levels are 10 dB below the main lobe as opposed to 28 dB below for the technique of this invention.
Since the staves are permanently fixed at particular angles, the array response is optimum for the designed range. When the focal distance is varied electronically from the designed range, grating lobe levels will increase. In FIG. 11 at 36, the calculated grating lobe to main lobe rejection ratio is plotted as a function of electronic focal distance for several values of R SF . It will be observed that the resulting grating lobes are lower at all ranges from zero to twice the value of R SF compared to a conventional array. Further, the maximum range at which grating lobes are of concern may be less than the maximum operating range of the sonar. Thus R SF might be chosen as somewhat less than half of the maximum operating range to obtain optimal grating lobe rejection over the ranges of interest. This case might arise if the projector pattern could be confined in such a way that the receive array grating lobes fall outside the project pattern beyond some range and are thus not of interest.
In summary, this invention significantly improves the beam patterns of very high resolution sonar arrays at all ranges by means of an ingenious combination of electronically varied space factor focus and mechanically fixed stave tilt angles.
The invention described herein can be applied equally well to linear arrays, curved arrays (including irregular shapes), and to slightly aperiodic arrays that are operated in the nearfield. The basic principle of the invention could also be applied to phased radar arrays. | A pulsed transmission, single frequency, high resolution sonar system has duced grating (side) lobes achieved by employing mechanically fixed antenna array stave tilt angles together with electronic focussing in which phase shifts are substituted for time delays. | 8 |
RELATED APPLICATION
[0001] This patent application claims the benefit of U.S. Provisional Application No. 62/365,231, filed Jul. 21, 2016, entitled “Trailer Sway Simulator,” which is incorporated herein by reference.
BACKGROUND
[0002] This invention generally relates to tools for educating customers who rent moving trailers. More particularly, it relates to an apparatus for simulating a vehicle traveling on a road and towing a trailer, wherein the apparatus includes a scale model towing vehicle and trailer combination positioned on a moving belt of a treadmill. The apparatus has a speed control and a remote control steering mechanism to demonstrate how the vehicle/trailer towing combination will react to vehicle operator inputs under varying conditions, including variations in weight distribution of the trailer load.
[0003] Many of the public have misconceptions about the cause and prevention of towing related accidents and the importance of trailer loading. It is an object of the present invention to provide an educational tool to help dispel these misconceptions by educating persons who use moving trailers as to how a vehicle/trailer combination will react under certain towing conditions.
[0004] Another object of the present invention is to provide a simulator that can physically demonstrate the importance of properly loading a trailer as well as showing the corresponding relationship of speed and avoidance of towing related crashes.
[0005] Additional objects and advantages of the invention will be set forth in the description that follows, and in part will be apparent from the description, or may be learned by practice of the invention. The objects and advantages of the invention may be realized and obtained by means of the instrumentalities and combinations pointed out in the appended claims.
SUMMARY
[0006] To achieve the foregoing objects, and in accordance with the purposes of the invention as embodied and broadly described in this document, there is provided an apparatus for simulating a vehicle traveling on a road and towing a trailer. In one embodiment, the apparatus includes a motorized belt with a surface movable at a variable speed in a longitudinal direction and a support frame including a cross member disposed above the motorized belt. A model towing vehicle is positioned on the belt movable surface and includes a vehicle steering assembly for turning the front wheels of the vehicle and a servo motor adapted to control the steering assembly in response to a servo control signal. The model towing vehicle is coupled to the frame cross member via a coupling arm so that the vehicle can move laterally when the motorized belt is in motion in the longitudinal direction. A model trailer is adapted for coupling to the rear end of the model towing vehicle and includes removable weights for simulating weight distribution in a life size trailer. A steering control assembly includes a steering wheel and a servo driver configured to provide the servo control signal in response to the operation of the steering wheel. In this configuration, when the motorized belt moves in the longitudinal direction, an operator can operate the steering control mechanism to steer the model towing vehicle laterally with respect to the motorized belt.
[0007] In an advantageous embodiment, the steering wheel is disposed in a generally vertical orientation to the rear of the model towing vehicle. The apparatus can include a camera for capturing track level images of the operation of the model towing vehicle or the model trailer. The support frame can be mounted to a storage box bottom platform configured to mate with a storage box top section that is configured to fit over and encase the apparatus.
[0008] A trailer sway simulator according to the present invention provides an educational tool that can be used to educate the public on the importance of properly loading a trailer by demonstrating the stability of such a trailer as well as the instability of an improperly loaded trailer. By demonstrating the reaction of vehicle/trailer towing combinations that have different trailer load distributions, it allows the potential driver to see the stability of a properly loaded trailer in comparison to an improperly loaded trailer. By allowing a user to manually steer the model towing vehicle, the simulator can simulate how a specific vehicle/trailer towing combination will react to driver inputs under the modeled conditions. With this visual education tool, customers are less likely to improperly load their trailer, which should result in fewer crashes from vehicles towing trailers.
[0009] A trailer sway simulator according to the present invention can also physically demonstrate the relationship between towing speed and the likelihood of a crash with an improperly loaded trailer as well as the importance generally of reducing vehicle speed, particularly in the case of a trailer sway or whipping situation; it can be used to disprove the misconception held by some people of increasing speed to reduce trailer sway or whipping.
[0010] Because the simulator can be used with model trailers having single or double axle configurations, different axle locations, and different tongue lengths, it can help teach how towing combinations with these different trailer configurations will react differently under the modeled conditions. Moreover, the simulator can be customized to show the impact of misaligned trailer axles or other variable trailer conditions and the effect if such conditions on stability of the towing combination.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate the presently preferred embodiments of the invention and, together with the general description given above and the detailed description of the preferred methods and embodiments given below, serve to explain the principles of the invention.
[0012] FIG. 1 is a side perspective view of one embodiment of a trailer sway simulator according to the present invention, showing the model towing vehicle and model trailer positioned on the motorized belt surface of the apparatus.
[0013] FIG. 2 is an end perspective view of the trailer sway simulator embodiment of FIG. 1 .
[0014] FIG. 3 is a wiring diagram showing the steering control assembly and model towing vehicle of the trailer sway simulator embodiment of FIG. 1 .
[0015] FIG. 4 is a perspective front view of the model towing vehicle of the embodiment of FIG. 1 showing the the vehicle connected to the frame cross member via the coupling arm.
[0016] FIG. 5 is an enlarged perspective view of the front end of the model towing vehicle of FIG. 4 showing the connection between the coupling arm and the front end of the vehicle frame.
[0017] FIG. 6 is a perspective view of the model towing vehicle of the embodiment of FIG. 1 with the body shell removed and showing the vehicle frame and the components mounted to it.
[0018] FIG. 7 is a bottom view of the top cover of the steering control box of the embodiment of FIG. 1 showing components of the control box.
[0019] FIG. 8 is a side view of the single-axle model trailer of the embodiment shown in FIG. 1 .
[0020] FIG. 9 is an end perspective view of another embodiment of a trailer sway simulator according to the present invention.
[0021] FIG. 10 is a side perspective view of the trailer sway simulator of FIG. 9 .
[0022] FIG. 11 is another perspective view of the trailer sway simulator of FIG. 9 .
[0023] FIG. 12 is an enlarged view showing the steering wheel mounted to the trailer sway simulator of FIG. 9 .
[0024] FIG. 13 is an enlarged top perspective view of the trailer sway simulator of FIG. 9 showing a camera housing.
[0025] FIG. 14 is an enlarged top perspective view of the trailer sway simulator of FIG. 9 showing how the simulator is mounted to a storage box bottom platform.
DETAILED DESCRIPTION
[0026] Reference will now be made in more detail to presently preferred embodiments of the invention, as illustrated in the accompanying drawings. While the invention is described more fully with reference to these examples and drawings, the invention in its broader aspects is not limited to the specific details, representative devices, and illustrative examples shown and described. Rather, the description which follows is to be understood as a broad, teaching disclosure directed to persons of ordinary skill in the appropriate arts, and not as limiting upon the invention.
[0027] It will be appreciated that terms such as “upper,” “inner,” “outer,” “vertical,” “horizontal,” “bottom,” “below,” “top,” “side,” “inwardly,” “outwardly,” “downwardly” and “lower” and other positionally descriptive terms used in this specification are used merely for ease of description and refer to the orientation of the referenced components as shown in the figures. It should be understood that any orientation of the components described herein is within the scope of the present invention. The term “generally” as used in this specification is defined as “being in general but not necessarily exactly or wholly that which is specified.” For example, “generally perpendicular” is used herein to indicate components that are in general, but not necessarily exactly or wholly, perpendicular.
[0028] In the drawings, the reference numeral 10 designates a trailer sway simulator in accordance with the invention. Referring to FIGS. 1-8 , one embodiment of the sway simulator 10 includes a treadmill assembly 12 having a support frame 13 that supports a belt 14 that can be driven at a selected speed by a suitable drive mechanism (generally an electric motor and gear system) (not shown) of the type that is used in exercise treadmills. The support frame 13 includes a cross member 16 that is disposed above the belt surface 15 . A coupling arm 21 is rotatably attached at one end to the cross member 16 and at the other end to the scale model towing vehicle 20 , with the vehicle positioned on the belt surface 15 . The model towing vehicle 20 includes a frame 22 (see FIG. 6 ) and a removable body shell 23 . A model trailer 40 is hitched to the rear of the model towing vehicle 20 .
[0029] A control panel 17 permits the user to select the speed at which the belt 14 is driven and includes a display 18 for displaying a speed of belt surface 15 relative to the model towing vehicle 20 based on the selected drive speed of the belt 14 . When the belt drive mechanism is turned on, the belt surface 15 moves in the direction D shown in FIG. 1 , thereby providing relative movement between the belt surface 15 and the model towing vehicle 20 and trailer 40 to simulate the movement of a towing vehicle/trailer combination over a road surface. As the belt surface 15 moves, the model towing vehicle 20 can be remotely steered by a user with a steering wheel 52 as described in more detail below.
[0030] Referring to FIGS. 3 and 6 , a vehicle steering assembly 24 is mounted to the towing vehicle frame 22 and can turn a set of front wheels 25 to steer the vehicle. A vehicle servo motor 60 is mechanically coupled to and controls the vehicle steering assembly 24 to turn the vehicle front wheels 25 . Removable weights 26 are mounted to the towing vehicle frame 22 and are selected and placed to simulate the weight distribution of an actual, life-size towing vehicle. The frame 22 has a front connector 28 attached to the frame front end 30 for rotatably connecting to the coupling arm 21 and a tow hitch 32 (see FIGS. 1 and 8 ) attached to the rear end 34 for coupling to the model trailer 40 .
[0031] Referring to FIGS. 1-2 and 8 , the model trailer 40 includes a frame 42 to which removable weights 44 can be mounted near the trailer front end 46 and rear end 48 to simulate load distribution in an actual, life-size trailer. Although the model trailer 40 shown in the figures has a single-axle configuration, it will be understood upon reading this specification that other configurations (e.g., a double-axle configuration and configurations with different tongue lengths) can be used to model various configurations of actual, life-size trailers.
[0032] Referring to FIGS. 2-3 and 8 , a user steering control assembly 50 is mounted to the simulator support frame 13 and includes a steering wheel 52 which an operator can use to turn the vehicle front wheels 25 and steer the model towing vehicle 20 when the belt 14 is moving. As shown in FIGS. 3 and 8 , an L-shaped pivot arm 53 is mounted to the shaft of the steering wheel 52 . One end of the pivot arm 53 is mounted to two tension springs 54 , which provide a suitable resisting force when the steering wheel 52 is turned in either direction. The other end of the pivot arm 53 is coupled via a linking mechanism 55 to a servo driver 56 . The linking mechanism 55 translates the rotational motion of the steering wheel to a rotating input knob of the servo driver 56 , which in turn outputs a servo control signal in response to the rotation of the input knob. The servo driver 56 is powered by a power supply 58 . The servo driver 56 is electrically coupled to a vehicle servo motor 60 on the model towing vehicle 20 via control signal wires 57 connecting the output of the server drive 56 to a receiving board 59 on the model towing vehicle 20 . The receiving board 59 receives the control signal from the servo driver 56 and in response to that signal, controls the vehicle servo motor 60 to turn the vehicle front wheels 25 . In this configuration, a user can remotely steer the model towing vehicle 20 with the steering wheel 51 .
[0033] Appendix A and Appendix B provide additional information regarding a suitable servo driver, receiving board and servo that have been used in one embodiment of the sway simulator 10 .
[0034] FIGS. 9-14 show another in one embodiment of the trailer sway simulator 10 . As shown in to FIGS. 9-12 , in this embodiment the steering control assembly 50 and steering wheel 52 are is mounted in a generally vertical orientation on the simulator support frame 13 to the rear of the model towing vehicle 20 . In this configuration, the simulator provides a better simulation of the act of driving and the user can get a better sense of how swerving while driving affects the trailer. The steering control assembly 50 includes a hanger member 64 for removably hanging the steering control assembly 50 from a cross member 66 of the simulator support frame 13 . This allows the lateral position of the steering control assembly 50 to be adjusted as can be seen by comparing the position of the steering control assembly 50 shown in FIG. 9 versus that shown in FIG. 12 .
[0035] The embodiment of FIGS. 9-14 also includes a camera housing 68 (see FIG. 13 ) for holding a video camera (not shown) that records the operation of the simulator when it is powered on. In one embodiment, the video camera is installed at track level to provide a “ground level” view of the operation of the simulator.
[0036] In addition, in the embodiment of FIGS. 9-14 the simulator support frame 13 is mounted to a storage box bottom platform 70 as can bee seen in FIGS. 10, 11 and 14 . The storage box bottom platform 70 is configured to receive a storage box top section 72 (see FIG. 13 ), which can fit over and encase the trailer sway simulator 10 . In this configuration, the trailor sway simulator 10 can be easily and quickly boxed for shipment.
[0037] From the foregoing, it can be seen that the apparatus of the present invention possesses numerous advantages. It can provide a tool for educating the public on the importance of properly loading a trailer by demonstrating the stability of such a trailer as well as the instability of an improperly loaded trailer. It can physically demonstrate the relationship between towing speed and the likelihood of a crash with an improperly loaded trailer as well as the importance of reducing vehicle speed in the case of a trailer sway or whipping situation. It can help teach how towing combinations with different trailer configurations will react differently under the modeled conditions and can be customized to show the effect of variable trailer conditions on the stability of the towing combination.
[0038] Upon reading this disclosure, additional advantages and modifications will readily occur to those skilled in the art. Therefore, the invention in its broader aspects is not limited to the specific details, representative devices, and illustrative examples shown and described. Accordingly, departures may be made from such details without departing from the spirit or scope of the general inventive concept. | An apparatus for simulating a vehicle traveling on a road and towing a trailer, wherein the apparatus includes a scale model towing vehicle and trailer combination positioned on a moving belt of a treadmill. The apparatus has a speed control and a remote control steering mechanism to demonstrate how the vehicle/trailer towing combination will react to vehicle operator inputs under varying conditions, including variations in weight distribution of the trailer load. | 6 |
BACKGROUND OF THE DISCLOSURE
In the use of vehicles in extremely cold environments, as for example a crawler tractor in Alaska during the winter, an operator sometimes finds that the hydraulic fluid increases in viscosity to a magnitude sufficient to make the hydraulic system slow to respond. One of the principal locations at which the hydraulic fluid becomes excessively viscous is in the relatively long conduits which provide the fluid pathway between the control valve and the hydraulic cylinders which actuate the clutch and brakes of the crawler tractor. During extended operation without clutch actuation, the fluid in these long conduits can cool to a value at which the pump pressure is slow to move the viscous fluid in the conduit upon actuation of the control valve.
This invention solves the problem of hydraulic line "freeze up" during inactive periods of the associated work element by providing means for substantially continuously passing hydraulic fluid between the control unit and the hydraulic cylinder.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a diagrammatic view of a portion of a hydraulic system of a vehicle having the apparatus of this invention;
FIG. 2 is a diagrammatic, enlarged view of a portion of the hydraulic system showing the control valve and associated hydraulic conduits; and
FIG. 3 is a diagrammatic view of a portion of the apparatus of FIG. 2 with the spool of the control valve positioned at another location.
DETAILED DESCRIPTION OF THE INVENTION
Referring to FIG. 1, a vehicle hydraulic system 10 is provided for controllably passing hydraulic fluid to a hydraulically actuated cylinder 12 of a work element (not shown), for example a vehicle clutch or brake. The hydraulic system 10, as is known in the art, has a fluid reservoir 14, a pump 16, and a control valve 18 connected between the pump 16 and cylinder 12 and positioned a relatively great distance from the cylinder 12.
A conduit 20 is connected to an intake of the pump 16 for passing fluid from the reservoir 14 to the pump 16. A first means 22, for example a conduit, is provided for passing fluid from the pump 16 to the control valve 18, a second means 24, for example another conduit, is provided for passing fluid from the control valve 18 to the hydraulic cylinder 12, and a third means 26, for example another conduit, is provided for returning hydraulic fluid from the control valve 18 to the reservoir 14.
Referring to FIG. 2, the control valve 18 has a chamber 28 and first, second, and third ports 30,32,34 in fluid communication with the chamber 28. Each of the ports 30,32,34 is connected to a respective one of the first, second, and third means 22,24,26 for passing hydraulic fluid, as set forth above.
A spool 36 is slidably positioned within the housing chamber 28 and is movable in response to actuating control means 38, such as a brake or clutch pedal. The spool 36 is movable between a first position (FIG. 2) and a second position (FIG. 3). At the first position, a fluid pathway is open from the pump 16, through the control valve 18, and to the reservoir 14. At the second position, a fluid pathway is open from the pump 16, through the control valve 18, and to the hydraulic cylinder 12, and is of a magnitude sufficient for actuating said cylinder 12 by fluid passing through the pathway to the cylinder at a preselected rate.
In this invention, a fourth port 40 is opened into the control valve chamber 28 at a first end portion 42 of the valve 18. A circulating conduit 44 has one end connected to the fourth port 40 and the other end connected to the cylinder 12 or the second means 24 at a location immediately adjacent the hydraulic cylinder 12.
Fourth means 46 provides a fluid pathway from the pump 16, through the control valve 18, through the circulating conduit 44, through a portion or all of the second means 24, back through the control valve 18, and through the third means 26 to the reservoir 14 at the first position of the spool 36, as shown in FIG. 2. At the second position of the spool 36, the fourth means 46 provides for blocking the fluid pathway from the pump 16 to the circulating conduit 44 and provides a fluid pathway from the pump 16, through the control valve 18 and to the hydraulic cylinder 12 for the actuation thereof.
The fourth means 46 is provided by constructing the valve with openings such as holes, slots, or grooves at preselected locations relative to the travel limits of the spool 36.
Referring to FIGS. 2 and 3, a first opening 48, here a curvilinear hole, opens at one end on a side of the spool 36, extends through a portion of the spool 36, and opens on the spool first end 50. The first opening 48 can be a groove, an orifice, or other configuration, but is of a construction sufficient for communicating said first and fourth ports 30,40 through said first opening 48 at the first position of the spool (FIG. 2) and spacing said first opening 48 from the first port 30 at the second position of the spool 36 (FIG. 3) for blocking fluid communication of the first port 30 with the fourth port 40.
A second opening 52, such as a groove for example, is positioned on a middle portion 54 of the spool 36. The second opening is of a construction sufficient for communicating the second and third ports 32,34 at the first position of the spool 36 (FIG. 2) and, at the second position of the spool 36, spacing said second opening 52 from the third port 34 while communicating said first and second ports through said second opening 52.
In the embodiment shown in the drawings, the control valve 18 has a housing 56 having a removable end cap 58 with said fourth port 40 extending through said end cap 58.
During use of the hydraulic system, fluid from the pump 16 is circulated through the control valve 18, conduits 24,44 and back to the reservoir during periods when fluid is not being delivered to cylinder 12. Therefore, the fluid in the conduits between the control valve 18 and the cylinder 12 is not in a quiescent, exposed position for detrimentally increasing the viscosity thereof in response to chilling.
Other aspects, objects, and advantages of this invention will become apparent from a study of the specification, claims, and the drawings. | A hydraulic system for use in extremely cold environments has a pump for passing hydraulic fluid from a reservoir to a hydraulic cylinder of a work element via a control valve that is positioned a relatively great distance from the hydraulic cylinder. Fluid pathways are provided for substantially continuously moving hydraulic fluid between the control valve and hydraulic cylinder during operation of the pump. | 1 |
TECHNICAL FIELD
The present request of invention patent deals with a textile dying process of cellulosic fibers in recycled dye baths without performing any intermediate depuration treatment, with reactive and direct dyes for the cellulosic fibers and disperse dyes for polyester, recycling both the water already used in a previous dying as well as all products that have been added and have not been absorbed by the textile substrate, in addition to the remains of disperse dyes that have not been depleted in the previous dying.
FOUNDATIONS OF THE TECHNIQUE
Any dying process, such as those carried out until now, requires an aqueous bath in a ratio between 5 L and 20 L per Kg of textile substrate, to which a number of auxiliary products are added (humectants, sliders, dispersers, etc.) of an organic nature and other compounds (neutral salts, acids and alkalis), which are not consumed during the dying process, or consumed only partially, besides the dyes: disperse for polyester and direct for cellulosic fibers that deplete themselves between 90% to 99% and also reactive ones also for cellulosic fibers, with a yield ranging from 60% to 90%, even if in this case the residual dye it not apt for a later dying of the same cellulosic fibers, since 10% to 40% of dye remains in its non-reactive, hydrolyzed form.
Due to a reduction in the availability of water for industrial processes, with a progressive cost increase, both in impounding and in softening and decalcifying and depuration for its discharge or recycling, for reasons of environmental protection it is necessary to consider all technical possibilities of treating water as still another reagent in the process and to look for more appropriate conditions for its direct recycling, as well as to its use and the use of all the other auxiliary products and other compounds that are not spent in the dying process. This is so because, besides cutting down on their needs and consumption, it allows a resulting advantage regarding the current depuration system for the discharge of residual waters, since only biodegradable or flocculable products can be extracted from residual waters by secondary treatments (physico-chemical or biological) whereas soluble sodium salts may be extracted only through inverted osmosis. The latter has a price tag unattractive for the industry at this moment and yields brine as a byproduct in a volume from 30% to 40%, which can be discarded only through discharge into the oceans and is not eliminated—these salts produce a progressive salification of the superficial beds and/or underground waters with the inconvenience this represents both on an environmental level and for the use of downstream river waters.
DETAILED DESCRIPTION OF THE INVENTION
This way, once the necessary studies and surveys have been performed on a laboratory level, as well as their validation on an industrial level in some concrete production plants, one proposes the following invention regarding dying processes with the direct recycling of dying baths already used without passing by any intermediate physico-chemical and/or biological depuration treatment: the textile dying process of cellulosic fibers and their blends and polyester and its blends with recycled dye baths, without performing any later depuration treatment, comes up only through a mechanical withholding filter of fibers and particles that may have been loosened from the textile substrate used in the dying process that preceded the next recycling.
The goal of said process is described in detail and both in the common aspects for cellulosic fibers and polyester and in the particular and specific aspects of the bath recomposition in the three cases mentioned:
Disperse Dyes—Polyester Direct Dyes—Cellulosic Fiber Reactive Dyes—Cellulosic Fibers
The direct recycling of dye baths applies to any kind of current dye machines usually used according to the way the textile substrate (fiber tuft thread or yarn and plane or knitted fabrics) presents itself when dye processes by depletion are carried out, and it suffices to connect the machine or machine bank carrying out the same dye processes to an additional tank, situated on a lower level, on the same level or on a level above the machines, with a capacity of Σ i=1 n (o′qVi). The Vi is the individual volume of each machine, with the corresponding injection pumps (according to the status level of each machine and tank), allowing to send a residual bath of each machine to the tank, and from it to each machine for a new dye. Plus the coupling of a mechanical filter on the outlet of each machine or a single filter situated at the tank input, to which all conduits coming from the machines are connected.
The tank must include a thermometer next to the bath outlet channel, as well as a system allowing to easily extract samples from residual baths for their measurement and adjustment in the laboratory in the necessary cases and appropriate measurement systems of outflow and/or volumes that go in and out of the tank, both for an individual machine and a bank of machines that carries out the same process.
The studies and surveys carried out by the inventors of this proposed process have shown the sensitivity levels of each disperse dye, whereas its use in recycled dye baths is very particular vis-à-vis the variety of the distribution. This applies especially to the first recyclings, until a non-variable status can be achieved for its tinctorial parameters, in which it is possible to produce color deviations when these process types are started from a new bath, practically from the 5th to the 8th recycling, depending on the volume of the extracted bath, as the dye machine varies (80%-87.5%) as well as the volume of clean water to be added in each case for the following dye in a recycled bath (20%-12.5%)
For this reason, according to the color to be obtained in each dye and until acquiring enough experience with the usually used dyes (it is recommended the use of a trichromy with total compatibility on a wide range of intensity of the three dyes), it is necessary, especially in the 10 first recyclings, to confirm and adjust formulas in laboratory before starting a new industrial process, after being analyzed by U-Vis spectroscopy the residual concentrations of the dyes in the bath to be recycled, by taking a 5 ml sample from this bath and adding NN′ Dymethyl-Formacide (5 ml) until a totally transparent solution is obtained and by comparison with the corresponding calibration straight lines for each dye in the three wave longitudes of maximum absorption of the specter achieved.
Once the new dye formula is adjusted according to the wanted color, the dying process takes place according to the following form:
The residual bath available volume is sent again to the dying machine, with the exact measurement, as appropriate to it. The volume of clean water that is lacking to reach the ratio of the wanted bath (minimum 10% of the total) is added, minus the volume that will be used to dissolve the auxiliary and dye products. The amounts of auxiliary products (humectants, slider, anti-reducer, etc.) that were lacking are added, due to the volume of the added clean water. It is added the amount of acetic acid (or of another organic acid usually used due to the added clean water and after checking the bath's pH. It is added the amount of acetic acid (or another organic acid usually used due to the added clean water and the bath pH is checked. The necessary amounts of dye are added according to the dying formula, previously discounted from the total volume necessary for dying. The necessary amounts of dye are added according to the dye formula, previously discounted from the total volume necessary for dying.
After these operations, the temperature at the beginning of the procedure must be 60° C. at the most and, before starting the dying, the pH is checked once again and corrected if necessary.
In this following dying process, that is: heating gradient (ΔT/Δt ° C./min), the maximum temperature of the process and the threshold time and the cooling time must be appropriate, considering the intensity of the color to be achieved, the types of dyes to be used (low, medium or high diffusion) and the features of the PES own substrate (in fabrics, the final cooling may lead to fixed wrinkles).
The bath cooling may stop at 80° C. or 70° C. and the machine is emptied into the additional tank until preparation of the next dying with the recycled bath.
Later, rinses, washes, usual reducing wash in each case of polyester dying, whether normal or in microfiber, are carried out.
This process requires that the polyester textile substrate must be purged prior to its dying for, otherwise, according to the nature and amount of impurities, unrecoverable interferences may be produced when the dying baths are systematically recycled.
The recycling of residual baths of cellulosic fibers for dying with direct dyes is very similar in its features, precautions and valuations as the recycling with dispersed dyes, as indicted in section 2.1.
The main differences are as follows:
The cellulose substrate, in the case of natural fibers (cotton, linen, bamboo, etc.) must be previously whitened and, due to the solidity of direct dyes, one usually uses clear/medium hues, which must also be chemically bleached. In the case of artificial fibers (viscose, Lyocell, etc.), the case will be similar to those indicated for polyester. The ratio of the recycled bath is notably lower than the availability in polyester, since, as they are hydrophilic materials, water withholding is superior (30%-20%). The stationary state is achieved with the lowest number of recyclings (3 to 6), as the ratio of clean water added in each recycling is increased. The proof and adjustment of formulas will be carried out in this case by taking 9 mL of initial residual bath and adding 1 mL of pyridine in order to achieve a totally transparent solution apt for its measurement by UV-Vis spectroscopy. It is recommended the use of totally compatible trichromes of identical sensitivity to salt or to the temperature (B or C types, according to the SDC), whereas dyes of good equalization (A type) are not recommended as it is more difficult to reproduce the color.
Once the dying formula for the new bath to be recycled is adjusted, the process is carried out as follows:
The residual bath available volume is sent again to the dying machine, with its exact measurement. The lacking volume is added with clean water, according to the wanted bath ratio, except the sum of the volumes to be added with auxiliary products, dyes and neutral electrolyte. The lacking auxiliary products are added by being dosed according to the total clean water volume added. The dyes are added and, according to the laboratory-adjusted formula, previously dissolved. According to the types of dyes being used and their sensitivity level to salt, one may add the lacking electrolyte (according to the added total clean water), whether chlorine or sodium sulfate, also previously dissolved in the total clean water, at the beginning of the dying or at the end of the heating stage, according to the usually employed equalization control system.
After such operations, the dying process is started at a temperature that should not exceed 50° C., the bath is heated up to its boiling point, with the gradient appropriate to the dyes and the color intensity, and boiling and, later, cooling, are carried out like the usual processes in each concrete dying. After the machine is emptied into the auxiliary tank, the rinses and later treatments are made as usual, according to the type of used dye.
On both described processes, 2.1 and 2.2, the following elements are recycled:
A high percentage (70-90%) of dye water. This same percentage of auxiliary products, neutral salts and acid. A small percentage of dye that usually remains in the residual bath, since a 100% depletion is never achieved and depends on each type of dye and dying intensity, ranging from 5 to 20% of the initial dye.
The recycling of residual dye baths of cellulosic fibers with reactive dyes substantially differs from the two previously shown ones since, during the dying process, reactive dyes undergo a partial reaction of hydrolysis that makes impossible to recycle it in a later dying process. Not long ago, studies on recycling were focused on using hydrolized reactive dye as the dye for dying other textile fibers (polyamide, wool, silk), shown by the inventors of this patent that, even if it is not possible to recycle these dyes to dye cellulosic fibers, it also does not interfere in the result of the new dye with residual bath, to which must be added all reactive dye as if in the case of dying in clean water.
Even if the process is applicable to any kind of reactive dye, possible interferences will be smaller the bigger the yielding of the reaction, as it happens with bi- and trifunctional dyes.
In this process, the main advantage in the recycling of residual baths lies in the considerable savings of neutral salts (sodium chloride or sulfate), which spectacularly bears upon the non-salinity of cleansed residual waters for their flow-off, a critical aspect in certain countries and zones, where a clear risk of salinity occurs both in superficial river waters and in underground aquifers.
For this recycling process, it is not necessary to carry out the residual dye measurement, since it does not make part of the dye to be fixed to the following dye and, for this reason, the stages to be carried out are:
Previous adjustment of the pH of the residual bath at 7, with chlorhydric acid, as in the previous process the alkaline pH is finalized (approx. 9.5-10.5) as well as the calculation of the amount of sodium chloride produced in said neutralization. Resending of the neutral residual bath to the dye machine and addition of the clean water volume necessary, according to the wanted bath ratio, minus the volume that will be used in dye dissolutions, auxiliary products, neutral electrolyte and alkali. Addition of the lacking auxiliary products due to the total volume of the clean water added. Start of the process, consisting of: Addition of the previously dissolved dyes; Addition of the electrolyte necessary to reach the nominal concentration, minus the sodium chloride produced in the neutralization of the previous residual bath; or perhaps: Dosing of the dye and lacking neutral electrolyte as previously indicated, according to the linear, progressive or regressive curves. Heating, or keeping the temperature on a neutral stage, as the usually followed procedure. Addition of all usual amount of alkali, according to the dye and intensity of the dying, dosing according to the available systematics and installations. Keeping the indicated time and temperatures in alkaline medium according to the dyes and intensities of the dying.
Also in this dying, the natural textile substrate should have been previously made non-crude (and whitened according to the color intensity) and in the initial recyclings it is advisable to check and make the adjustments to the laboratory formulation, considering the particular sensitivity of each dye and reactive group to the presence of the initial hydrolized dye in the bath.
Once the machine has been emptied into the auxiliary tank, one proceeds with rinsing and soaping the material—this is always recommended and a sine-qua-non for medium and intense color shades.
The inventors, in collaboration with Golden Química do Brasil, have studied and established trichromes of dyes and auxiliary products appropriate to cut down to a minimum the interferences by substances which, by addition of dyes (crystalline gels) and their own textile substrates, will accumulate in residual baths, until reaching a stationary state in which such concentrations remain practically constant, thus assuring maximum reproduction of the color, as well as the quality and solidity of the dyes in directly recycled residual baths.
At the same time, all details of the process that ensure its continuity and validity have been established, upon the use of recycled baths in a complete closed cycle system, which constitutes the usual work form of a textile dyer plant.
Despite the fact that the invention is detailed, it is important to understand that it does not limit its application to the details and stages described here. The invention is capable of other modalities or of being practiced or executed in a variety of ways. It must be understood that the terminology employed here is for the purpose of description and not limitation. | A textile dyeing process for dyeing cellulosic fibers and polyester and their respective blends with other fibers in recycled dyeing baths without carrying out any intermediate depuration treatment and using reactive and direct dyes for the cellulosic fibers and dispense dyes for polyester is described. The process recycles both the water already used in a previous dyeing cycle and all added products that have not been absorbed by the textile substrate, as well as the rest of the disperse dyes that had not been depleted in the previous dyeing cycles. | 3 |
BACKGROUND OF THE INVENTION
Field of the Invention
The present invention relates to a method and a device for digitally measuring an analog voltage that varies over a predetermined voltage range, and more particularly to the use of such a device for measuring a temperature.
In automotive electronics, it is often necessary to measure the temperature of certain fluids, oil or coolant, or devices such as a catalytic converter for oxide reduction of the exhaust gases from a motor vehicle, or an oxygen sensor used in a device for regulating the air and fuel mixture supplied to the engine of such a vehicle. Currently, a suitable temperature pickup furnishes an analog electrical signal to an analog/digital converter, which furnishes a digital expression of the temperature measurement that can be used by a computer that forms part of an open- or closed-loop control unit provided in the vehicle.
The signal output by the pickup is normally an electrical voltage. When the temperature monitored becomes the subject of closed-loop control, this control keeps the signal within a predetermined voltage range. Thus oxygen sensors are known that are associated with a heating resistor actuated in such a way as to maintain the sensor temperature within a very narrow temperature range, for example 650° to 750° C., in which range the signal output by the sensor can be used. If the sensor temperature is evaluated on the basis of the temperature of the heating resistor, whose resistance is a function of that temperature, then the voltage picked up at its terminals to do so also varies within a range whose values are fixed by the limits of the aforementioned temperature range.
It has also been desirable for the temperature of the catalytic converter, around an optimal operating temperature of 850° C., for example, to be known by a computer with a fixed precision of several percent. If a thermocouple is used to do so, then its output voltage varies in a corresponding manner within a predetermined voltage range.
The problem then arises of the precision of the digital measurement of the image voltage of the temperature observed. This precision is a function of the reference voltage V ref of the converter and of the number of bits n of the measurement N that it furnishes. In the aforementioned applications, measuring the voltage is of interest only within a predetermined voltage range, which a priori does not correspond to the dynamics of the digital measurement chain used, which depends on parameters (V ref , n) that are independent of this range.
SUMMARY OF THE INVENTION
Accordingly, the object of the present invention is to furnish a method of digital measurement of a voltage that varies within a predetermined range, with the aid of a measurement chain including an analog/digital converter, with which method a maximum measurement precision within this range can be attained.
Another object of the present invention is to furnish such a method that is suitable for measuring an analog voltage affected by the voltage furnished by an electrical power source, which may possibly fluctuate, as is the case of the voltage furnished by the battery of a motor vehicle, by which method a digital measurement freed of any influence of the fluctuations of the voltage can be obtained.
Furthermore, an object of the invention is to use a device for implementing this method that can be used particularly in a temperature measurement chain.
These objects of the invention as well as others that will become apparent in the ensuing description, are attained with a method by which
a) the voltage to be measured is amplified with a gain proportional to the ratio between the reference voltage of the analog/digital converter used and the length of said voltage range;
b) the reference voltage is amplified with a gain proportional to the ratio between the lower value of the voltage range to the breadth of this voltage range; and
c) the analog input of the converter is supplied with the difference between the thus-amplified voltages.
As will be noted in further detail hereinafter, this method makes it possible to adapt the converter dynamics to the length of the voltage range, so as to advantageously maximize the precision of the measurement furnished by the converter.
In a variant of the method according to the invention, adapted for measuring an analog voltage affected by the voltage furnished by a possibly fluctuating electrical supply source, the converter is supplied with a reference voltage proportional to the fluctuating electrical voltage, in such a way as to make the digital measurement furnished by the converter independent of the fluctuations in said voltage.
This variant is especially useful in motor vehicle electronics, because as is well known, the source of electrical voltage normally used there is the vehicle battery, whose output voltage currently exhibits very major fluctuations, for example from 4 to 15 V for a nominal voltage of 12 V.
For implementing this method, the invention furnishes a device, including an analog/digital converter and a source of reference voltage (V ref ) for supply to this converter; this device is notable in that it includes amplification means supplied with the analog voltage (U e ) to be measured and with the reference voltage (V ref ) in order to furnish to the analog input of the converter an output voltage (U s ) such that: ##EQU1## where U 1 and U 2 , respectively, are the lower and upper values of the predetermined voltage range.
Further characteristics and advantages of the present invention will become more apparent from the ensuing description and from a study of the accompanying drawing, in which:
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a graph useful for illustrating the method of the present invention;
FIG. 2 is a functional diagram of a device for implementing the method of the present invention;
FIG. 3 illustrated one embodiment of the device schematically shown in FIG. 2;
FIG. 4 is a diagram of a device for measuring a temperature with the aid of a thermocouple, implementing the method of the invention; and
FIG. 5 is a diagram of a device for measuring the temperature of an oxygen sensor, corresponding to another use of the method of the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
On the U e axis of FIG. 1, a predetermined voltage range (U 1 , U 2 ), within which a voltage U e to be measured varies, is plotted. Also shown in FIG. 1, on the other axis, is the graph of the output N of an analog/digital converter supplied with a reference voltage V ref .
If U 1 <U 2 <V ref , then one can see that the range of variation dN of the output of the analog/digital converter corresponding to the range (U 1 , U 2 ) is much narrower than the dynamics ΔN of the converter, at the expense of the precision of the digital measurement of the voltage to be measured, whose resolution is proportional to the reference voltage V ref and inversely proportional to 2 n , where n is the number of bits of the output of the converter.
In the present invention, the precision of the voltage measurement to be made is maximized by adapting the voltage range [0, V ref ] of the converter to the voltage range [U 1 , U 2 ]. To do so, the voltage U 1 is made to correspond to 0 in the range to be measured of the converter, and the voltage U 2 is made to correspond to the voltage V ref . This measurement range is then graduated over the totality of the 2 n levels of the output N of the converter, not over a fraction of these 2 n levels, which thus improves the precision of measurement of a voltage U e that is within this measurement range. A computer, supplied with the output of the converter and loaded with the voltage value U 1 corresponding to the 0 of the converter output, thus establishes the voltage U e with the greatest possible precision, taking into account the characteristics of the analog/digital converter used.
Turning to FIG. 2 of the accompanying drawing, a device will be described that is designed for the implementation of the present invention. A pickup 1 furnishing a voltage signal U e to be measured is connected to amplification means 2, whose output U s supplies an analog/digital converter 3, which in turn is supplied with a reference voltage V ref .
According to the present invention, the amplification means 2 are further supplied by the reference voltage V ref and furnish an output voltage U s such that:
U.sub.s =K·U.sub.e -K'·V.sub.ref (1)
where K and K' are constants established as follows.
According to the invention, the voltage U 1 and U 2 correspond respectively to the voltages 0 and V ref at the output of the amplification means 2, and hence by employing the equation (1) above:
0=K·U.sub.1 -K'·V.sub.ref
V.sub.ref=K·U.sub.2 -K'·V.sub.ref
The following relationships can be found: ##EQU2##
The relationship (1) is then expressed as follows: ##EQU3##
Thus by amplifying the voltages U e and V ref in the means 2 with the amplification gains K and K', which are calculated as indicated above, and by supplying the analog input of the converter 3 with the difference U s between these amplified voltages, a measurement of the voltage U e whose precision is as high as possible can be taken from the output N of the converter and from a recorded digital measurement of the voltage U 1 ; the pitch of this precise measurement of the voltage U e is equal to V ref /2 n , where n is the number of bits of the output N of the converter 3. Thanks to the amplification means 2, an output N=0 of the converter 3 corresponds to an input voltage U e =U 1 , and N=2 n corresponds to a voltage U e =U 2 .
One embodiment of the device schematically shown in FIG. 2 has been shown in FIG. 3 of the accompanying drawing. The amplification means comprise a differential amplifier 2', supplied on the one hand with the voltage U e to be measured, via charge resistors R 1 and R' 1 , between its inverting and noninverting inputs, respectively, and on the other is supplied with an offset voltage as a function of the reference voltage V ref of the converter. A reaction resistor R 2 is mounted between the output of the amplifier and the inverting input, in order in combination with the resistor R 1 to establish the gain of the amplifier relative to the input voltage U e , while the reference voltage V ref of the converter is connected to one terminal of a resistor R 3 , whose other terminal, which is in common with the resistor R 2 , is connected to the inverting input of the amplifier. The noninverting input is connected to ground through a resistor R' 2 . Under these conditions, it can be demonstrated that the relationship (2) above becomes as follows: ##EQU4##
A first use of the invention, for measuring a voltage that varies within a predetermined range furnished by a thermocouple, is illustrated in FIG. 4. The measurement chain represented includes a thermocouple whose "hot" junction 4 is at a temperature Θ 1 to be measured, while its reference junction 5 is at a temperature Θ 2 . It is known that such a thermocouple furnishes a voltage as follows:
U.sub.e=f (Θ.sub.1 -Θ.sub.2)
The voltage U e supplies a device that is identical to that of FIG. 3. The same reference numeral is used for devices or elements that are identical or similar in FIGS. 3-5. It is understood that a computer can determine the voltage of the temperature Θ 1 from the function f and from a measurement of the voltage U e , with the temperature of Θ 2 being assumed to be fixed and known.
When the temperature Θ 2 the reference junction is likely to vary (as is the case for example when it is at ambient temperature), then according to the invention means are provided that are sensitive to the temperature of this junction and are capable of furnishing a correction signal, enabling the computer to suitably correct the calculation of the temperature Θ 1 .
To do so, a temperature pickup, such as a thermistor 6, is disposed in proximity with the reference junction 5, and the variations in the resistance of the thermistor 6 cause the voltage at the middle point of a resistor bridge (R 4 ,6), which is supplied with the voltage V ref for example, to vary. The computer periodically orders a switching means 7 to connect the middle point of the bridge to the input of the converter 3, which then furnishes the computer with a digital measurement of the temperature Θ 2 . Such a device is useful especially when a temperature sensor must be located at a distance far from the computer, as is the case for instance when the temperature of a catalytic converter for oxide reduction of the exhaust gases from an internal combustion motor driving a motor vehicle is measured.
Another "motor vehicle" use of the present invention is shown in FIG. 5. This is the measurement of the temperature of an oxygen sensor 8 heated by a heating resistor R ch . As has been seen above, the temperature of such a sensor must be kept within a relatively narrow range. To that end, a device for closed-loop control of this temperature controls the supply to the heating resistor. This resistor may be considered in thermal equilibrium with the sensor 8 that it heats. The temperature of the sensor can be known from that of the heating resistor assumed to be in thermal equilibrium with the sensor, which resistor varies with the temperature, as is well known. This measurement is made by picking up the voltage U e from the middle point of a bridge comprising the resistor R ch and a fixed resistor R 5 , the resistors being connected in series between the positive pole of the vehicle battery and ground. This voltage varies inversely with the variation in the resistance of R ch , when this resistor has a positive temperature coefficient, as is conventionally the case. The measurement of this voltage by a computer supplied with the output of the converter 3 of a device that is also in accordance with those shown in FIGS. 3 and 4 accordingly makes it possible to arrive at the temperature of the sensor 8.
In a motor vehicle, the voltage +V bat furnished by the battery is capable of very major fluctuation, as has been seen above. Such fluctuations accordingly adulterate the measurement made, since they affect the supply to the heating resistor.
This disadvantage is overcome, according to the present invention, by taking the reference voltage V ref of the converter from the voltage +V bat furnished by the battery, in such a way that these voltages vary in the same direction. Automatic compensation for the effects of fluctuation in the battery voltage is thus obtained. Since the battery voltage is generally higher than the maximum voltage that the converter can withstand at its reference voltage terminal, it is only a fraction αV bat (α<1) of the output voltage of the battery that supplies the device according to the invention. It is understood that the present invention is not limited to the embodiments described and shown, which are given solely by way of example. The invention is accordingly advantageously applicable as well to the digital measurement of any variable that is accessible by means of a voltage varying within a predetermined range, and not only to measuring a temperature. | A method wherein (a) a voltage to be measured (U e ) is amplified with a gain proportional to the ratio between the reference voltage (V ref ) of an analogue-to-digital converter (3) and the extent of the voltage range; (b) the reference voltage (V ref ) is amplified with a gain proportional to the ratio between the lower terminal (U 1 ) of the voltage range and the extent of the voltage range; and (c) the analogue input of the converter (3) is supplied with the resulting amplified voltage difference. The method is useful for measuring a temperature by means of a thermocouple and measuring the temperature of an oxygen sensor in a motor vehicle exhaust line. | 5 |
CLAIM OF PRIORITY
[0001] The present application is a continuation of patent application Ser. No. 10/732,934 filed Dec. 11, 2003, which claims priority under 35 USC §119(e) from Provisional Application Ser. No. 60/436,159 filed Dec. 23, 2002.
BACKGROUND OF INVENTION
[0002] The present invention is directed to the reduction of protein deposition on surfaces. The invention provides compositions and methods for inhibiting the deposition of protein on the surfaces of medical devices, particularly biomedical and prosthetic devices. The invention is based on the discovery that certain polymers and related copolymers comprising the monomer n-isopropylacrylamide (NIPAM) significantly inhibit protein deposition on the surfaces of contact lenses.
[0003] Proteins adsorb to almost all surfaces and the minimization or elimination of protein adsorption has been the subject of numerous studies, such as those reported by Lee, et al., in J. Biomed. Materials Res., vol. 23, pages 351-368 (1989). Sensors, chromatographic supports, immunoassays, membranes for separation, biomedical implants, prosthetic devices (e.g., contact lenses) and many other devices or objects can be adversely affected by protein adsorption. A method and/or means for treating the surfaces of such objects so as to prevent or reduce protein deposition would therefore be quite advantageous.
[0004] The use of NIPAM-containing polymers to modify surfaces and control protein deposition on glass and silicon substrates has been previously described. The following publications provide further background regarding such modifications:
[0005] 1. Kidoki, et al., Langmuir, 17, pp. 2402-2407 (2001);
[0006] 2. Bohanon, et al., J. Biomater. Sci. Polymer Edn., Vol. 8, No. 1, pp.19-39 (1996);
[0007] 3. International (PCT) Patent Publication No. WO 02/30571 A2 (Sudor);
[0008] 4. U.S. Pat. No. 6,447,897 (Liang, et al.);
[0009] 5. U.S. Pat. No. 6,270,903 (Feng, et al.); and 6. Huber, et al., Science, Vol. 301, pp. 352-354, Jul. 18, 2003.
[0010] The above-identified publications do not disclose or suggest that NIPAM-containing polymers could be used to modify the surfaces of medical devices, such as contact lenses, and to control protein deposition and release on such surfaces.
[0011] The terms “soft” and “hard” relative to contact lenses are generally associated with not only the relative hardness of the respective types of lenses, but also the type of polymeric material from which the lenses are formed. The term “soft” generally denotes a contact lens that is formed from a hydrophilic polymeric material, such as hydroxyethyl methacrylate or “HEMA”, while the term “hard” generally denotes a lens that is formed from a hydrophobic polymeric material, such as polymethylmethacrylate or “PMMA”. The surface chemistry and porosity of the hard and soft lenses is quite different. Soft lenses typically contain a large amount of water, are quite porous, and bear ionic charges on the exposed surfaces of the lenses, while hard lenses are considerably less porous and generally do not bear ionic surface charges.
[0012] The ionic surfaces and porous nature of soft contact lenses can lead to significant problems when the lenses come into contact with the tear film due to the complex composition of the tear film, which is largely comprised of proteins, lipids, enzymes and various electrolytes. Tear components include albumin, lactoferrin, lysozyme and a number of immunoglobulins. The uptake of proteins from the tear fluid onto the lens is a common problem and depends on a number of factors, including the nature of the materials from which the lens is made.
[0013] Soft contact lenses act as efficient substrates for protein deposition and adsorption. This fouling can lead to dehydration of the lens and instability of the tear film, resulting in discomfort and lack of tolerance in the wearer. Adsorption of proteins can also facilitate bacterial colonization and this can increase the risk of vision-threatening infections.
[0014] In view of the potential fouling of contact lenses and the problems created by such fouling, as discussed above, it is generally accepted that contact lens cleaning must be a regular part of a patient's lens care regimen. Many different types of cleaning agents have been utilized in the past for this purpose. Cleaning agents such as surfactants and enzymes are typically incorporated into contact lens care products to remove protein deposits. However, the use of these agents can lead to irritation, and in cases where rubbing and cleaning regimens are required, there is a possibility that the cleaning agents will not be used properly or will be used in a manner that damages the lenses. In view of the foregoing problems, it would be advantageous if the surfaces of contact lenses could be modified so as to prevent or reduce the adsorption of proteins to the surfaces.
[0015] Various attempts have been made to reduce protein deposit formation on contact lenses. The following patents may be referred to for further background regarding such attempts:
[0016] U.S. Pat. No. 4,411,932 describes the use of polymeric alcohols and polymeric ethers, including poly(ethylene glycol), polyethylene oxide and polyethylene glycol methyl ether, as prophylactic agents against soilant deposits on contact lenses;
[0017] U.S. Pat. No. 6,274,133 (Hu et al.) describes the use of cationic cellulose polymers to prevent the build-up of lipids and proteins on a silicone-hydrogel lens;
[0018] U.S. Pat. No. 6,323,165 (Heiler, et al.) describes the use of charged polyquaternium polymers to block the binding of proteins to hydrophilic contact lenses; and
[0019] U.S. Pat. No. 6,096,138 (Heiler, et al.) describes the use of polyquaternium polymers such as Luviquat® (BASF), which is a mixture of vinylpyrrolidone and vinylimidazolium moieties that can bind to hydrophilic contact lens materials, so as to block the binding of proteinaceous materials to the lenses.
[0020] These prior attempts to reduce protein binding have drawbacks. For example, cationic polymers may act as irritants upon contact with the eye when utilized at high concentrations. Additionally, due to the positive charge character of these macromolecules, complex formation with anionic surfactants or other components of CLC products may lead to flocculation and phase separation in the formulation, which is a significant problem. Accordingly, there is need for new approaches to provide protein resistant surfaces.
[0021] Due to the trend toward use of extended wear lenses, it would be useful to be able to provide contact lens wearers with a contact lens surface that inhibits adsorption of proteinaceous matter for extended time periods, without compromising the safety of the patient. The polymer should also be compatible in contact lens care solutions when storage, disinfection and/or cleaning are desired by the patient. The present invention is directed to satisfying these needs.
SUMMARY OF INVENTION
[0022] The present invention is directed to the use of polymers that are surface active and exhibit a temperature response in aqueous solutions. The polymers and related polymers (e.g., co-polymers) are formed from a N-isopropylacrylamide (“NIPAM”) monomer.
[0023] The present invention is based on a discovery that the NIPAM polymers and related polymers may be utilized to inhibit protein deposition on the surfaces of hydrogel contact lenses. The NIPAM polymers provide unique solution properties, and it has been discovered that these properties can be employed in formulations where protein resistant hydrogel surfaces are desired.
[0024] As discussed above, there is a need for improved approaches for modifying the adsorption of proteins on the surfaces of contact lenses. The present invention is based on a discovery that the NIPAM polymers described herein are uniquely suited for this purpose.
[0025] The NIPAM polymers described herein may be employed in various manners in order to achieve modification of contact lens surfaces and surfaces of other medical devices. For example, contact lenses can be stored in solutions containing NIPAM polymers prior to being worn. This prophylactic approach allows the polymers to form a protective layer on the surface of the lenses before the consumer even exposes the lenses to tear fluids containing protein. The NIPAM polymers may also be incorporated in multi-purpose solutions for treating contact lenses on a daily basis. Chemical grafting on surfaces to form permanent coatings of NIPAM polymers is another method for preparing protein resistant surfaces.
[0026] In addition to contact lenses, the surface modification techniques described herein may be applied to various medical devices where protein resistant surfaces are desired, such as intraocular lenses, catheters, cardiac stents, prosthetics, and other medical devices that undergo prolonged exposure to proteins during use in or on the bodies of humans or other mammals.
[0027] Although not wishing to be bound by theory it is believed that the NIPAM polymers described herein have a range of inherent physical properties (e.g., low interfacial free energy, hydrophilic-hydrophobic properties, very low toxicity, dynamic surface mobility and steric stabilization) that enable these polymers to exhibit superior protein inhibiting characteristics.
BRIEF DESCRIPTION OF DRAWINGS
[0028] FIG. 1 is a graph showing the results of the tests described in Example 1; and
[0029] FIG. 2 is a graph showing the results of the tests described in Example 3.
DETAILED DESCRIPTION OF THE INVENTION
[0030] The NIPAM polymers utilized in the present invention have the following formula:
wherein n is a whole number of from 10 to 3,000.
[0031] The NIPAM polymers utilized in the present invention include various types of polymers that comprise the above-described monomer. The polymers may be formed entirely from the NIPAM monomer identified above, or other monomers can be incorporated into the polymer by copolymerizing the NIPAM monomer with other monomers, such as acrylic acid, acrylamide, N-acetylacylamide, N,N-dimethylacrylamide and butyl methacrylate. In addition, modified polymers or copolymers containing the NIPAM monomer can be prepared by functionalization of end groups, preparation of block copolymers, and cross-linking of polymers. All such polymers, copolymers or modifications thereof are referred to herein as either “NIPAM polymers” or “PNIPAM”. The NIPAM polymers utilized in the present invention will typically have molecular weights of from 1,000 to 300,000 Daltons. The polymers are available from Polymer Source, Inc., Dorval, Quebec (Canada).
[0032] The amount of PNIPAM utilized in the compositions of the present invention will vary depending on the form of the compositions and the intended use thereof. The concentration of PNIPAM utilized will generally be an amount sufficient to obtain a solution surface tension of less than 50 milliNewtons per meter (“mNm −1 ”) at room temperature (23° C.).
[0033] The above-described NIPAM polymers are surface active, and therefore will readily adsorb to most types of surfaces. Factors such as the type of surface (hydrophobic versus hydrophilic), temperature, buffer and excipients will influence the interaction between the polymers and a surface, and will influence the magnitude of the interactions.
[0034] The above-described PNIPAM polymers may be combined with other components commonly utilized in products for treating contact lenses, such as rheology modifiers, enzymes, antimicrobial agents, surfactants, chelating agents or combinations thereof. The preferred surfactants include anionic surfactants, such as RLM 100, and nonionic surfactants, such as the poloxamines available under the name “Tetronic®”, and the poloxamers available under the name “Pluronic®”. Furthermore, a variety of buffering agents may be added, such as sodium borate, boric acid, sodium citrate, citric acid, sodium bicarbonate, phosphate buffers and combinations thereof.
[0035] The compositions of the present invention that are intended for use as CLC products will contain one or more ophthalmically acceptable antimicrobial agents in an amount effective to prevent microbial contamination of the compositions (referred to herein as “an amount effective to preserve”), or in an amount effective to disinfect contact lenses by substantially reducing the number of viable microorganisms present on the lenses (referred to herein as “an amount effective to disinfect”).
[0036] The levels of antimicrobial activity required to preserve ophthalmic compositions from microbial contamination or to disinfect contact lenses are well known to those skilled in the art, based both on personal experience and official, published standards, such as those set forth in the United States Pharmacopoeia (“USP”) and similar publications in other countries.
[0037] The invention is not limited relative to the types of antimicrobial agents that may be utilized. Examples of antimicrobial agents that may be used include: chlorhexidine, polyhexamethylene biguanide polymers (“PHMB”), polyquaternium-1, and the amino biguanides described in co-pending U.S. patent application Ser. No. 09/581,952 and corresponding International (PCT) Publication No. WO 99/32158, the entire contents of which are hereby incorporated in the present specification by reference.
[0038] The preferred antimicrobial agents are polyquaternium-1, and amino biguanides of the type described in U.S. patent application Ser. No. 09/581,952 and corresponding International (PCT) Publication No. WO 99/32158. The most preferred amino biguanide is identified in U.S. patent application Ser. No. 09/581,952 as “Compound Number 1”. This compound has the following structure:
It is referred to below by means of the code number “AL-8496”.
[0039] The ophthalmic compositions of the present invention will generally be formulated as sterile aqueous solutions. The compositions must be formulated so as to be compatible with ophthalmic tissues and contact lens materials. The compositions will generally have an osmolality of from about 200 to about 400 milliosmoles/kilogram water (“mOsm/kg”) and a physiologically compatible pH.
[0040] The compositions of the present invention and the ability of those compositions to reduce protein adsorption on contact lenses are further illustrated by the following Examples. Unmodified (i.e., non-ionic) NIPAM polymers and modified (i.e., end terminated with —COOH groups) NIPAM polymers were added to appropriately buffered solutions to demonstrate the ability of these polymers to reduce protein adsorption when utilized as components of buffered multi-purpose solutions for treating contact lenses. A simple means of producing PNIPAM-modified surfaces was used in order to mimic the contact lens disinfection/cleaning regime typically used by the consumer.
EXAMPLE 1
[0041] The tests described below were conducted to evaluate the ability of NIPAM polymers to modify contact lens surfaces and thereby reduce protein adsorption.
[0000] Materials/Methods
[0042] The materials and methods utilized in the evaluation were as follows:
[0043] Chemicals
[0044] Lysozyme (Sigma, Chicken egg white, grade 1, 3× crystalline), Trifluoroacetic Acid Anhydrous (Sigma, Protein sequencing grade) Acetonitrile (EM Science, HPLC grade), Sodium Phosphate Monobasic, Monohydrate (Sigma, ACS reagent grade), Sodium Phosphate Dibasic, Anhydrous (Sigma, ACS reagent grade), Sodium Chloride (Sigma, ultra pure grade), Unisol®4 (Alcon Laboratories, Inc., preservative-free. pH-balanced saline solution for rinsing)
[0045] The NIPAM polymers utilized are identified in Table 1 below. These polymers were purchased from Polymer Source Inc. and were used without further purification.
TABLE 1 Polymer Type M v × 10 3 M w /M n P2991-NIPAM Non-ionic 46,380 2.36 P604-NIPAM Non-ionic 71,600 2.44 P1239-NIPAM Non-ionic 122,000 2.50 P2426F2-NIPAM-COOH Anionic 132,000 1.29
[0046] Lenses
[0047] Acuvue (Vistakon, a division of Johnson & Johnson Vision Products, Inc) lenses were used as the substrate in this study. The lenses had the following parameters: 42% etafilcon A, 58% water, FDA Group IV lens. Diameter, 14.0 mm; base curve, 8.8 mm; power, −2.00.
[0048] Formulations
[0049] The NIPAM and NIPAM-COOH polymers identified in Table 1 were formulated at pH 7.8 in a buffered vehicle containing 1.5% sorbitol, 0.6% boric acid and 0.32% NaCl. In a beaker, all the formulation chemicals except for the NIPAM polymers were weighed out and purified water was added (QS to 95%). The pH was adjusted to 7.8 with NaOH/HCl. The NIPAM polymer was weighed out and added to the buffer solution and this was stirred overnight to solubilize the polymer. The test formulations are shown in Table 2 below; the concentrations are expressed as weight/volume percent (“w/v %”):
TABLE 2 Formulation Numbers 9591-47C Component 9591-47A 9591-47B (Control) P2991-NIPAM 0.034 0.017 — Sorbitol 1.5 1.5 1.5 Boric Acid 0.6 0.6 0.6 Sodium Chloride 0.32 0.32 0.32 Purified Water QS QS QS pH 7.8 7.8 7.8
The test formulations were evaluated for their prophylaxis behavior using lysozyme as the model protein, as described below.
[0050] Preparation of Deposition Solution
[0051] Phosphate Buffered Saline (PBS) 1.311 g of monobasic sodium phosphate (monohydrate), 5.74 g of dibasic sodium phosphate (anhydrous), and 9.0 g of sodium chloride were dissolved in deionized water and the volume was brought to 1000 mL with deionized water, and pH was adjusted (as necessary). The final concentrations of sodium phosphate and sodium chloride were 0.05 M and 0.9%, respectively. The final pH was 7.4.
[0052] Lysozyme Solution
[0053] A 1.5-mg/mL lysozyme solution was prepared by dissolving 750 mg of lysozyme in 500-mL phosphate buffered saline pH adjusted to 7.4.
[0054] Lens Extraction Solution (ACN/TFA)
[0055] A lens extraction solution was prepared by mixing 1.0 ml of trifluoroacetic acid with 500-mL acetonitrile and 500 ml of deionized water. The pH of the solution ranged from 1.5 to 2.0.
[0056] Lens Presoak Procedure
[0057] Each lens was immersed in 3-mL of each test formulation and allowed to sit at room temperature overnight. The next morning, the lenses were removed from the test formulations and dabbed lightly on a towel.
[0058] Lens Deposition Procedure (Physiological Deposition Model)
[0059] Each presoaked lens was immersed in a Wheaton glass sample vial containing 3-mL of lysozyme solution. The vial was closed with a plastic snap cap and incubated in a constant temperature water bath at 37° C. for 24 hours. Three additional lenses were included as controls to establish the total amount of lysozyme deposited. After incubation, the deposited lenses were removed from their vials and rinsed by dipping into three consecutive beakers containing 200 ml Unisol®4 or water to remove any excess of the deposition solution.
[0060] Extraction and Determination of Lysozyme Extraction
[0061] The lenses were extracted with 5 ml of ACN/TFA extraction solution in a screw-capped glass scintillation vial. The extraction was done by shaking the vial with a rotary shaker (Red Rotor) at room temperature for at least 2 hours (usually overnight).
[0062] Calculations for the Determination of Lysozyme
[0063] Quantitative determination of the lysozyme of the lens extract was carried out using a fluorescence spectrophotometer interfaced with an autosampler and a computer. The fluorescence intensity of a 2 ml aliquot from each sample solution was measured by setting the excitation/emission wavelength at 280 nm/346 nm with excitation/emission slits of 2.5 nm/10 nm, respectively, and the sensitivity of the photomultiplier was set at 950 volts.
[0064] A lysozyme standard curve was established by diluting the lysozyme stock solution to concentrations ranging from 0 to 40 μg/ml, using the ACN/TFA extraction solution for the lens extract and the vehicle for the soaking solutions. The instrument settings for measuring the fluorescence intensity were the same for the lens extracts and lens soaking solutions.
[0065] The lysozyme concentrations for all of the samples were calculated based on the slope developed from the linear lysozyme standard curve. The % prophylaxis of each formulation was calculated by subtracting the amount of lysozyme in the lens extract from the amount of lysozyme from the control lenses (total deposit), then dividing that by the total deposit and multiplying by 100.
[0000] Results
[0066] FIG. 1 shows the % prophylaxis as a function of PNIPAM concentration (g/100 ml) for nonionic NIPAM polymers having molecular weights of 46,380; 71,600; and 122,000, respectively.
[0067] FIG. 1 shows that there was no significant PNIPAM molecular weight dependence on the % prophylaxis using the defined polymer concentrations. PNIPAM concentrations up to 0.2 g/100 ml gave % prophylaxis results of approximately 30%. With increasing PNIPAM concentrations above 0.2 g /100 ml the % prophylaxis could be increased to 50% to 60% using polymer concentrations between 0.4 g/100 ml and 0.65 g /100 ml. The % prophylaxis was not dependent on the molecular weight of the NIPAM polymers.
EXAMPLE 2
[0068] The prophylactic properties of NIPAM polymers were further evaluated using a 3-day cycling study. Two sets of lenses were prepared. One set was presoaked in the formulations shown in Table 2 before going into the lysozyme solution, whereas the other set was not. Both sets of lenses were then placed in the lysozyme solution for 8 hours (Day 1). At the end of the day all the lenses were rinsed and put in their respective formulations to soak overnight. The following day (Day 2), the lenses went back into the lysozyme for the day (8 hours). This was repeated to complete 3 cycles (3 Days). At the end of the experiment all the lenses were analyzed in accordance with the procedures described in Example 1. The results are presented in Table 3:
TABLE 3 Uptake of Amount Lysozyme Removed % Sample (ug/lens) sd (ug/lens) Prophylaxis sd 9591-47A(PS) 124.1 9.1 261.9 67.8 0.8 9591-47B(PS) 151.5 3.9 234.5 60.8 0.6 9591-47C(PS) 386.0 6.1 — — — 9591-47A 206.3 2.7 174.9 45.9 1.2 9591-47B 221.3 10.4 159.9 41.9 0.9 9591-47C 381.2 7.1 — — — PS = Presoaked
[0069] The results demonstrate that the buffered solutions containing a NIPAM polymer (i.e., P2991-NIPAM) were effective in reducing protein uptake in both the presoaked and non-presoaked lenses. For example, the presoaked lenses treated with solutions containing concentrations of 0.034% and 0.017% of the NIPAM polymer demonstrated prophylaxis values of 67.8% and 60.8%, respectively. For the non-presoaked lenses the prophylaxis values were 45.9% and 41.9% at concentrations of 0.034% and 0.017%, respectively.
[0070] The results set forth in Table 3 demonstrate that treatment of the lenses with a NIPAM polymer solution prior to exposure to proteins is preferable. However, the results also show that even when the lenses have already been exposed to proteins prior to an initial treatment with a NIPAM polymer solution, the uptake of protein is reduced when the lenses are subsequently treated with a NIPAM polymer solution. Thus, the results of this study confirm that the compositions of the present invention are effective in reducing the formation of protein deposits on contact lenses, even when the lenses are repeatedly exposed to protein contamination.
EXAMPLE 3
[0071] The prophylaxis work was extended to formulations containing the antimicrobial agent AL-8496 with unmodified NIPAM (non-ionic) and modified NIPAM (end functionalized with COOH) polymers. The formulations evaluated are shown in Table 4, below:
TABLE 4 Formulations for Microbiology Evaluation of PNIPAM Formulations Containing A Contact Lens Disinfecting Agent (AL-8496) Formulation Numbers 9591-44I Component 9591-44B 9591-44C 9591-44D 9591-44E 9591-44F (Control) P2991-NIPAM 0.087 0.21 P2426F2-NIPAMCOOH 0.040 0.10 0.25 AL-8496* 0.0004 0.0004 0.0004 0.0004 0.0004 0.0004 Tetronic ® 1304 0.1 0.1 0.1 0.1 0.1 0.1 Sorbitol 0.4 0.4 0.4 0.4 0.4 0.4 Sodium borate 0.2 0.2 0.2 0.2 0.2 0.2 Sodium citrate 0.6 0.6 0.6 0.6 0.6 0.6 Propylene glycol 1.0 1.0 1.0 1.0 1.0 1.0 Disodium edetate 0.05 0.05 0.05 0.05 0.05 0.05 pH 7.8 7.8 7.8 7.8 7.8 7.8 % Prophylaxis 37.4 ± 0.2 54.1 ± 1.0 51.0 ± 0.5 57.3 ± 0.4 62.8 ± 1.2 0.6 ± 0.0 *As base
[0072] The procedures utilized were the same as in Example 1. FIG. 2 shows the prophylaxis data obtained using the overnight soak model with lenses pre-soaked in the respective PNIPAM formulations.
[0073] FIG. 2 shows that the prophylaxis properties of the NIPAM polymers were retained in the presence of the antimicrobial agent AL-8496 and other formulation components, including cleaning ingredients (e.g., citrate and Tetronic® 1304). The data demonstrate that both unmodified and modified NIPAM polymers can be incorporated into multi-purpose contact lens care formulations without compromising the prophylactic properties of the polymers.
EXAMPLE 4
[0074] The disinfection activity of the formulations shown in Table 4 above was also evaluated. The results are shown in Table 5 below.
TABLE 5 Disinfection Properties of PNIPAM Formulations containing AL-8496 Time 9591- 9591- 9591- 9591- 9591- 9591- Microorganism (hrs) 44B 44C 44D 44E 44F 44I Candida 6 2.8 3.0 3.0 3.4 3.2 3.0 albicans 24 3.9 4.5 6.0 6.0 5.3 6.0 Serratia 6 2.7 6.2 2.8 2.7 2.6 2.6 marcescens 24 5.5 6.2 5.5 6.2 5.5 4.9 Staphylococcus 6 5.5 4.5 5.5 4.4 4.3 4.9 aureus 24 6.2 5.0 6.2 6.2 6.2 5.2
[0075] The results demonstrate that the NIPAM polymers did not adversely affect the antimicrobial activity of the antimicrobial agent AL-8496.
EXAMPLE 5
[0076] Several formulations were evaluated to compare the prophylaxis properties of PNIPAM with two well-known block co-polymers, Tetronic® 1107 and Pluronic® F127. The formulation components and prophylaxis results are given in Table 6, below.
[0077] The evaluation was carried out using the same procedures as outlined in Example 1. The buffered solution utilized as a control (10581-85J) did not exhibit any prophylaxis properties. However, as shown in Table 6, the compositions of the present invention containing PNIPAM at concentrations of 0.2% (10581-85B) and 0.4% (10581-85C) produced prophylaxis results of 56.2% and 63%, respectively.
[0078] In contrast, the solutions containing Tetronic® 1107 and Pluronic® F127 block co-polymers at concentrations of up to 0.8% did not produce any significant prophylaxis.
TABLE 6 Components 10581-85B 10581-85C 10581-85E 10581-85F 10581-85H 10581-85I 10581-85J PNIPAM P2991 0.2 0.4 — — — — — Tetronic ® 1107 — — 0.4 0.8 — — — Pluronic ® F127 — — — — 0.4 0.8 — Sorbitol 1.5 1.5 1.5 1.5 1.5 1.5 1.5 Boric Acid 0.6 0.6 0.6 0.6 0.6 0.6 0.6 Sodium Chloride 0.32 0.32 0.32 0.32 0.32 0.32 0.32 Purified Water QS QS QS QS QS QS QS pH 7.8 7.8 7.8 7.8 7.8 7.8 7.8 % Prophylaxis 56.2 + 0.1 63.0 + 0.4 0.00 + 2.3 4.1 + 2.2 0.0 + 2.1 0.0 + 0.9 0.8 + 1.0 | The use of NIPAM polymers to prevent or reduce the formation of protein deposits on the surfaces of medical devices is described. The invention is particularly directed to reduction of the adsorption of proteins on surfaces of contact lenses and other medical prosthetics. | 8 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates generally to vehicle passenger safety restraints and, more specifically, to an Improved Bus Seat Safety Restraint.
2. Description of Related Art
Mass transportation vehicles such as buses have been widely used in virtually every city and town in the developed world for decades. Generally speaking, these vehicles typically include two or more columns of bench seats aligned one behind the other with a minimum necessary distance between a seat and the seat behind it. It is uncommon to find automobile-type lap or shoulder restraints for the passengers on public transportation vehicles, apparently because passengers repeatedly fail to engage the belts, either due to carelessness or due to perceived discomfort. In general, then, there is not currently a widely used restraint system to prevent passengers of mass transportation systems from being tossed from their seats in the event of a vehicle collision or rollover.
This problem is particular egregious in the case of school buses. Many children ride the bus to and from school five days a week in all weather, traffic and road conditions. The high frequency of ridership under a variety of conditions indicates that it is inevitable that more children passengers will experience a collision while riding a bus than virtually any other passenger group. This is exacerbated by the fact that children can tend to be particularly unruly while riding the bus to and from school; the children cannot be relied upon to engage the current safety restraints, even if they were provided. What is needed, therefore, is a safety restraint system for vehicles with bench seats that is easy to use and to be monitored.
Majerus, U.S. Pat. No. 4,681,344 sought to solve this problem. The Majerus unit comprises a hinged, U-shaped bar attachable to the legs of each forward seat in a column and a releasable belt which holds the bar in a lowered position, laying across the passengers' laps, restraining them from striking the seat in front of them. When not in use, the Majerus belt is released, and the bar is pivoted up to the stowed position. There are three serious problems with the Majerus system: (1) the locking belt system is as difficult to enforce as a common lap belt—if the passenger pulls down the bar (i.e. to mislead the driver into believing that the bar is engaged), but fails to lock the belt, the system will not provide any restraint; (2) the Majerus belt extends from the bar to the seat at the aisle side of the seat, thereby trapping the restrained passengers in the seat until the belt is released; and (3) the system relies upon the passenger to adjust the belt until the bar is in the proper position—if the belt is left too loose, the bar won't provide restraint to the passengers, and may even be a hazard. What is needed, therefore, is a bus passenger safety restraint that is easily engaged, automatically adjusted, and easily verified as such by the bus driver. This system should further permit the passengers to easily egress in case of system malfunction.
Amabile, U.S. Pat. No. 4,796,913 sought to solve some of the Majerus problems. The Amabile device is also a hinged U-shaped bar attached to the next seat forward. The Amabile device differs from Majerus in that it attaches to the seatback frame directly and does not require a belt for engagement. The Amabile system comprises a pair of pivoting cam hinges at each end of the U-shaped bar attached to either side of the forward seatback frame. These cam hinges define three bar positions: an upper limit (stowed position), a lower limit, and a lower locked limit. The Amabile bar is automatically engaged in the lower locked limit position whenever the restrained passengers' inertia forces the bar forward and into the lower locked cam in the hinges.
One serious problem with the Amabile system is that it is only responsive to a passenger accelerating forward relative to the seats, such as in a front-end collision. The Amabile bar will not restrain the passengers in the event of a side collision, or in a bus rollover. Furthermore, the Amabile bar is not height-adjustable by the passengers for their particular thigh height. Once installed, the Amabile cam hinge has a set locked position that cannot be adjusted; it is conceivable that a passenger with sufficiently large thighs will prevent the bar from dropping down low enough to engage if a collision occurs. Finally, the Amabile bar is difficult to install in existing buses. In order to activate both cam hinges (i.e. on both ends of the bar), the cams must be aligned with each other to a very close tolerance. Misalignments due to seat frame bending or simply inconsistent installations may create a situation where one hinge's cam locks while the other hinge doesn't. What is needed, therefore, is a safety restraint system that engages and locks in front, and side collisions, and even in the event of vehicle rollover. The system should be easily installed and aligned on existing buses, and further should provide adjustability for differing passenger body types.
SUMMARY OF THE INVENTION
In light of the aforementioned problems associated with the prior devices, it is an object of the present invention to provide an Improved Bus Seat Safety Restraint. The preferred safety restraint will comprise a padded U-shaped bar. The bar has indexed stops at stowed, in-use and lower locked positions. It is an object that the bar lock and restrain the passenger when the vehicle experiences a side or front collision, or if the vehicle rolls over. It is a further object that the bar have a single, fixed pivot point. The preferred bar will further comprise a padded thigh pad that is height-adjustable to provide greater comfort to a wide variety of body shapes and sizes. It is a still further object that the restraint bar system be installable on both new and existing buses and the like.
BRIEF DESCRIPTION OF THE DRAWINGS
The objects and features of the present invention, which are believed to be novel, are set forth with particularity in the appended claims. The present invention, both as to its organization and manner of operation, together with further objects and advantages, may best be understood by reference to the following description, taken in connection with the accompanying drawings, of which:
FIG. 1 is a side view of a pair of school bus seats, the forward of which has a preferred device of the present invention installed thereon;
FIG. 2 is a back view of the forward seat of FIG. 1 depicting the restraint bar in the in-use and lower locked positions;
FIG. 3 is a back view, similar to FIG. 2, depicting the restraint bar in the stowed position;
FIG. 4 is a partial cutaway side view of a preferred aisle-side hinge assembly as it is attached to the front seat of FIG. 1;
FIGS. 5A and 5B are partial side views of the aisle-side hinge assembly of FIG. 4, depicting the rest and engaging positions of the weight;
FIG. 6 is a partial cutaway top view of the hinge assembly of FIGS. 4 and 5;
FIG. 7 is a partial cutaway bottom view of the hinge assembly of FIGS. 4-6;
FIG. 8 is a partial back view of the preferred hinge assembly of FIGS. 4-7;
FIGS. 9A and 9B are partial perspective views of the preferred shaft and spring of FIGS. 4-8 depicting the relationship between the spring and the indexing notches on the shaft;
FIGS. 10A and 10B are perspective views of the preferred restraint bar of the present invention depicting the action of the preferred thigh pad; and
FIGS. 11A and 11B are cutaway side view of the thigh pad of FIGS. 10A and 10B and the restraint bar of previous figures.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The following description is provided to enable any person skilled in the art to make and use the invention and sets forth the best modes contemplated by the inventor of carrying out his invention. Various modifications, however, will remain readily apparent to those skilled in the art, since the generic principles of the present invention have been defined herein specifically to provide an Improved Bus Seat Safety Restraint.
The present invention can best be understood by initial consideration of FIG. 1 . FIG. 1 is a side view of a pair of school bus seats 10 and 12 , with the forward seat 10 having a preferred device of the present invention installed thereon to restrain the person(s) seated in the next-rear seat 12 . The device includes a U-shaped restraint bar 14 in hinged attachment to the seat back 16 of the forward seat 10 . The restraint bar 14 may be pivoted into a stowed position 18 to permit passenger ingress to and egress from the next-rear seat 12 ; the hinge assembly (see FIGS. 4-10) preferably provides an indexed stop to hold the bar 14 in the stowed position 18 until it is pulled down, presumably by a passenger seated in the next-rear seat 12 . When pulled down from the stowed position 18 , the bar 14 will drop until it either reaches the passengers' thighs or reaches an indexed in-use position 20 . The system further preferably defines a lower locked position 22 that will permit the bar 14 to approach the seating surface 24 of the next-rear seat 12 no closer than the minimum thigh distance 26 . This minimum thigh distance 26 may be defined by law to be a distance sufficient to prevent crushing the passengers' legs. The system may include a bulkhead stop 27 , which is essentially a padded protrusion mounted to the bulkhead of the vehicle, positioned to prevent the bar 14 from traveling down further than the lower locked position 22 . If the seat back 16 happens to be deformed, such as in the event of a heavy rear impact, the bulkhead stop 27 will prevent the bar 14 from violating the minimum thigh distance 26 . It should be appreciated that one critical aspect of the present invention is the novel pivoting-and-locking action of the bar 14 that defines a single fixed hinge axis 28 about which the bar 14 pivots.
Turning to FIG. 2, we can view the restraint bar 14 from another perspective. FIG. 2 is a back view of the forward seat 10 of FIG. 1 depicting the restraint bar 14 in the in-use and lower locked positions 20 and 22 , respectively. As can be seen, the bar 14 is U-shaped, with a center section 30 and aisle- and window-side ends 32 and 34 extending forwardly where they are pivotally attached to the seatback 16 . As discussed above, the restraint bar 14 may pivot along the hinge axis 28 to in-use and lower locked positions 20 and 22 , respectively.
FIG. 3 is a back view, similar to FIG. 2, depicting the restraint bar 14 in the stowed position 18 . In the stowed position 18 , the bar's center section 30 extends above the top of the seat back 16 such that it is easily viewable by the bus driver desiring to check whether the bar 14 is being employed properly by the passenger.
Now turning to FIG. 4, we might discuss the novel functioning of the present invention. FIG. 4 is a partial cutaway side view of a preferred aisle-side hinge assembly 36 as it is attached to the front seat of FIG. 1 . It should be appreciated that both the aisle-side and window-side hinge assemblies are identical mirror images of one another; we simply focus on the aisle-side assembly 36 here for ease of understanding.
The hinge assembly 36 comprises a plurality of mounting brackets 38 made from a hardened material, such as steel, attached to the typically tubular frame 40 of the seat back 16 . The hinge assembly 36 can be attached at virtually any height along the seat frame 40 that is desired, depending upon the particular installation. A critical feature of the hinge assembly 36 is that virtually all components, with the possible exception of the end of shaft 42 , are contained within the seat cover 44 and/or the padding 46 surrounding the frame 40 . As such, all mechanical components of the hinge assembly 36 are hidden from view and protected from tampering and against injuring the passengers. Another preferred hinge assembly 36 may comprise “U”-bolts or other substitutes for the mounting brackets 38 , depending upon the particular installation requirements.
The restraint bar end 32 comprises, a frame 48 surrounded by rubberized padding thereover, and is fixedly attached to the shaft 42 , such that when the shaft 42 rotates on the hinge axis 28 , the restraint bar (see FIGS. 1-3) pivots upwardly and downwardly. The shaft 42 is further configured with a plurality of teeth 52 formed on its surface. A jaw member 54 is pivotally attached to the mounting brackets 38 in the vicinity of the shaft 42 . The jaw member 54 is also formed with teeth 56 thereon opposite the shaft teeth 52 . It should be obvious that if the jaw member 54 is pivoted such that the jaw teeth 56 engage the shaft teeth 52 , the shaft 42 will be prevented from rotating, which in turn will prevent the restraint bar (see FIGS. 1-3) from moving. As designed, the system may be configured to engage in the event of heavy braking or swerving of the vehicle, prior to any actual impact; it is unnecessary that the passenger strike the bar (see FIGS. 1 and 2) in order to engage the locking system.
The jaw teeth 56 are caused to engage the shaft teeth 52 when the jaw member 54 is forced to pivot by the rocking pad 58 . The rocking pad 58 is attached to, and rides on, the fulcrum 60 , such that when the fulcrum 69 is caused to rock back and forth, the rocking pad 58 will urge the jaw member 54 towards the shaft 42 . The fulcrum 60 rides atop the fulcrum bracket 62 , which is essentially a metal bracket attached to the mounting brackets 38 to provide a substantially horizontal surface upon which the fulcrum 60 may rest. Extending downwardly from the fulcrum 60 is the pendulum rod 64 , at the end of which is a weight 66 . It should be apparent, then, that the system functions like a pendulum such that when impact or gravitational forces cause the weight 66 and pendulum rod 64 to leave vertical alignment by a sufficient amount, the fulcrum 60 will rock, thereby causing the rocking pad 58 to urge the jaw member 54 towards the shaft 42 until the jaw teeth 56 engage the shaft teeth 52 .
To prevent the system from being damaged by excessive downward force being place on the restraint bar (see FIGS. 1 and 2 ), such as if a large child sits of bounces on it, the preferred hinge assembly may also include a pin 63 protruding radially from the shaft 42 and configured to engage a shaft stop 65 to prevent further rotation of the shaft 42 . Further detail regarding the shaft stop pin 63 and the shaft stop 65 is provided below in connection with FIGS. 5, 6 and 8 .
In order to prevent the bar 14 from being locked in position when the vehicle is struck from the rear, a weight stop 67 is provided. The weight stop 67 may be a protrusion from the mounting bracket 38 , or may actually be a feature of a metal enclosure for the hinge assembly 36 (not shown). The weight stop 67 is positioned to prevent the weight 66 from traveling backwards beyond the rest position (see below).
FIGS. 5A and 5B are partial side views of the aisle-side hinge assembly of FIG. 4, depicting the rest and engaging positions 68 and 70 of the weight 66 , provided to further illuminate the novel functioning of the present invention. As can be seen in FIG. 5A, the pendulum rod 64 is in vertical alignment with the fulcrum 60 and the weight 66 ; the weight 66 being in the rest position 68 . In this rest position 68 , the jaw member 54 is also “at rest”, its teeth 56 are not engaged with the shaft teeth 52 , and the shaft 42 is free to rotate about the hinge axis 28 .
FIG. 5B depicts the weight 66 in the engaging position 70 , wherein the weight 66 is no longer in vertical alignment with the pendulum rod 64 and the fulcrum 60 . In this case, the weight 66 has traveled forward, such as from the vehicle suffering a front-end collision. When the weight 66 reaches the engaging position 70 , the attached components have forced the jaw member 54 to pivot around the pivot shaft 72 until the jaw teeth 56 have engaged the shaft teeth 52 . Furthermore, if the vehicle drives up or down a severe enough incline, the weight 66 might also reach the engaging position 70 , thereby locking the shaft 42 (and restraint bar) from movement. This is an added safety benefit not available with the prior devices.
Still further, it should be understood that the actual location limit setting of the engaging position 70 is configurable by altering the length of the pendulum rod 64 , for example. It should also be appreciated that once the jaw teeth 56 and shaft teeth 52 are engaged, the shaft 42 will be released for rotation after the weight 66 drops to the rest position 68 and any rotational force on the shaft 42 is relieved (such as by slightly lifting the restraint bar). It can further be seen that the weight stop 67 will prevent the weight 66 from traveling backwards sufficiently past the rest position 68 to cause the jaw 54 to engage the shaft 42 .
FIG. 6 is a partial cutaway top view of the hinge assembly 36 of FIGS. 4 and 5. As depicted here, the mounting brackets 38 are preferably attached to the frame 40 by a plurality of mounting bolts 74 . The shaft 42 is also configured to rotate in one of the mounting brackets 38 around the hinge axis 28 . Another aspect shown here is the novel means for attaching the restraint bar 14 to the shaft 42 . The preferred restraint bar 14 is formed with an adapter 78 at its end. The adapter 78 is of the same cross-section as the shaft 42 , and has a mating surface configured to be accepted by a V-notch 76 formed in the end of the shaft 42 . As long as the adapter 78 is firmly attached to the shaft 42 , such as by a bolt or the like, the mating surface of the adapter 78 will engage the V-notch 76 to prevent rotational motion between the shaft 42 and the bar 14 . To remove the restraint bar 14 , one need merely remove the attaching means (i.e. a bolt), and the adapter 78 will slip out of the V-notch.
Also depicted in FIG. 6 is the spring 80 . The spring 80 attaches between the shaft 42 and the mounting bracket(s) 38 to urge the shaft 42 to rotate and cause the restraint bar 14 to be biased towards the stowed position (see FIGS. 1 - 3 ). This spring action will assist the passenger in lifting the bar 14 up and out of the way, but will not be strong enough to cause the bar 14 to lift without manual passenger assistance. Furthermore, the shaft stop pin 63 is depicted located on the restraint bar 14 side of the hinge assembly 36 to reduce the torque generated within the system when engaging the shaft stop (see FIGS. 4 and 8 ).
FIG. 7 is a partial cutaway bottom view of the hinge assembly 36 of FIGS. 4-6 presented to show additional detail regarding these components. It can be seen that the preferred jaw member 54 extends over substantially the entire exposed length of the shaft 42 , such that all resultant forces created between the jaw member 54 and the shaft 42 when their teeth (see FIGS. 4-5) are engaged are adequately transferred to the seat frame 40 . Further depicted is the beveled aperture 82 formed in the fulcrum bracket 62 to allow the pendulum rod (see FIGS. 4-5) to pass through and attach to the fulcrum (see FIGS. 4-5) and still permit the weight 66 a full range of motion.
FIG. 8 is a partial back view of the preferred hinge assembly 36 of FIGS. 4-7, provided to give insight into the response of the hinge assembly 36 in the event of a side collision to the vehicle. As discussed above, when at rest, the weight 66 will hang in vertical alignment with the pendulum rod 64 , such that the rocking pad 58 does not push the jaw member 54 to engage its teeth with those of the shaft 42 . When a lateral- or side-impact to the vehicle causes the weight 66 to move sufficiently left or right to reach one of the lateral engaging positions 84 , the fulcrum (see FIGS. 4-5) will cause the rocking pad 58 to push the jaw member 54 upwardly until its teeth are engaged with the shaft teeth (see FIGS. 4 - 5 ). Here, the shaft stop pin 63 and shaft stop 65 are also depicted; as can be seen, the preferred shaft stop 65 is inserted in a pair of cooperating apertures (not shown) in the mounting bracket 38 to provide a rigid stop for the shaft stop pin 63 and shaft 42 .
It should also be understood that vehicle rollover will also cause the weight 66 to reach one of the lateral engaging positions 84 , thereby engaging the jaw member 54 with the shaft teeth (see FIGS. 4 and 5 ).
Now turning to FIGS. 9A and 9B, which are partial perspective views of the preferred shaft 42 and spring 80 of FIGS. 4-8, we might discuss the relationship between the spring 80 shaft 42 . In its preferred form, the spring 80 will be formed with an arch 86 near its center. The arch 86 defines an indexing segment 88 at its apex. The indexing segment 88 is located and configured to engage the in-use indexing notch 90 and the stowed indexing notch 92 , which are formed in the shaft 42 . In addition to urging the restraint bar towards the stowed position, the spring 80 interacts with these indexing notches 90 and 92 to provide positive “stops” at the in-use and stowed positions. Other intermediate stops may be provided by forming the appropriate notches in the shaft 42 . Once “stopped”, the user need merely exert a minimum amount of force on the restraint bar in order to pop the indexing segment 88 out of the in-use indexing notch 90 . FIG. 9B depicts that the shaft 42 has now rotated until the indexing segment 88 has engaged the stowed indexing notch 92 . The shaft teeth 52 are also depicted to show that they do extend over a substantial portion of the shaft's 42 length. The indexed rotation of the shaft 42 will provide smoother, less jarring engagement than the prior devices.
Finally, turning to FIGS. 10A and 10B we may discuss still another novel aspect of the present invention. These figures are perspective views of the preferred restraint bar 14 of the present invention depicting the action of the preferred thigh pad 94 . The thigh pad 94 may simply be an oblong pad formed over the center section 30 of the restraint bar 14 . The thigh pad 94 is rotatable in the upward direction 96 and the downward direction 98 in order to provide the user with a comfortable place upon which to rest his or her arms and/or hands. Furthermore, the thigh pad 94 may be rotated to provide greater or less distance between the restraint bar 14 and the passengers' thighs, if desired.
While only the pendulum-type locking mechanism has been described heretofore, it is understood that (1) other locking mechanisms are conceived of for use in this invention, such as other forms or arrangements of jaw members and shafts; and (2) any accelerometer-type sensing system beyond the pendulum-fulcrum system may be used, depending upon the details of a particular installation.
Now turning to FIGS. 11A and 11B, we may discuss the details of the novel thigh pad 94 of the present invention. FIG. 11A is a cutaway side view of the thigh pad of FIGS. 10A and 10B, and FIG. 11B is a partial cutaway side view of the restraint bar 14 of the previous figures. The thigh pad 94 comprises a thigh pad frame 100 , preferably made from metal or other durable material. The frame 100 , like the rest of the restraint bar 14 , is surrounded by padding 50 , such as is commonly used in prior restraint bars. The pad 94 further has a durable cover 102 over the padding 50 and frame 100 , made from material which resists cutting, tearing or wear.
The frame 100 is further defined by a bore 104 , configured to accept the restraint bar frame 48 , and further includes a keyway 106 . The keyway 106 is cooperates with the key 108 such that the thigh pad 94 is permitted to rotate through it desired range of rotation 96 (in this case 130 degrees). The assist in assembly of the thigh pad 94 , the frame 100 , padding 50 (and possibly other elements) may be divided into two or more sections that are assembled around the restraint bar frame 48 .
Those skilled in the art will appreciate that various adaptations and modifications of the just-described preferred embodiment can be configured without departing from the scope and spirit of the invention. Therefore, it is to be understood that, within the scope of the appended claims, the invention may be practiced other than as specifically described herein. | An Improved Bus Seat Safety Restraint is disclosed. The preferred safety restraint comprises a padded U-shaped bar that has indexed stops at stowed, in-use and lower locked positions. The bar locks and restrains the passenger when the vehicle experiences a side or front collision, or if the vehicle rolls over. The bar preferably has a single, fixed pivot point. The bar further comprises a padded thigh pad that is height-adjustable to provide greater comfort to a wide variety of body shapes and sizes. Still further, the restraint bar system is installable and easily aligned on both new and existing buses and other mass transportation vehicles. | 1 |
[0001] The United States Government has rights in this invention pursuant to Contract No. W-7405-ENG-48 between the United States Department of Energy and the University of California for the operation of Lawrence Livermore National Laboratory.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to the production of phase shifting masks for extreme ultraviolet lithography (EUVL), and more specifically, it relates to systems and methods for directly writing patterns into the reflective multilayer coating of an extreme ultraviolet lithography phase shifting mask and providing a patterned absorber layer onto the EUVL mask.
[0004] 2. Description of Related Art
[0005] Phase shifting masks (also known as reticles) are commonly used as a resolution enhancement technique in optical lithography and the technology is well established and widely used in deep ultra-violet lithography systems. See U.S. Pat. No. 5,045,417, Okamoto et al., titled “Mask For Manufacturing Semiconductor Device And Method Of Manufacture Thereof” issued 1991. Current DUV masks are transmissive and are designed to alter both the phase and amplitude of the transmitted light. In particular, the alternating phase shifting mask (alt-PSM) has been developed to extend the resolution limit of DUV optical systems. The fundamental quantity of interest in determining lithographic resolution is the normalized image line slope (NILS) as this is what determines the sharpness of the lines that can be printed. A common factor used to estimate the smallest printable feature size is the k 1 factor of the printing process. For a printing system of a given numerical aperture (NA) operating at a given wavelength (λ) the critical dimension (CD) is given by:
CD = k 1 λ NA .
[0006] A lower CD means the ability to print smaller lines, and a smaller value of k 1 means that smaller lines can be printed on the same optical system. The factor k 1 is dependent on the design of the mask used. See U.S. Patent Application No. US2001/0021475, 2001, titled “Lithography Method And Lithography Mask” to Czech et al. For binary transmission masks, k 1 lies in the range of 0.5 to 0.7 (the Rayleigh limit of resolution). Halftone masks enable k 1 to be reduced to values of 0.38 to 0.55, whilst phase shift masks enable k 1 to lie in the range of 0.2 to 0.38.
[0007] Phase shift masks can improve the CD specification in a number of ways. These include, but are not limited to:
[0008] 1. Direct resolution enhancement By taking advantage of both intensity and phase modulation, it is possible to control more of the complex number space defining the optical wave-field leaving the mask, and therefore increase the information content of the light field. This can be used to directly reduce the k 1 factor, thus, the printable feature size.
[0009] 2. If k 1 can be improved, it is possible to reduce the NA for a given CD specification. High NA optics are generally larger and harder to fabricate than low NA optics, thus improving k 1 through phase shifting enables the specifications on the size and NA of the optics to be relaxed for a given CD specification, thereby reducing the cost of fabricating the optics set.
[0010] 3. Maintaining the CD specification by reducing k 1 and moving to a lower NA also increases the process window. Lower NA optics have a greater depth of focus, thus the focusing tolerances in the wafer plane are relaxed and it is possible to use more economical stages to scan the wafer.
[0011] 4. Flare control: Flare in the wafer plane can vary as the mask is scanned due to variations in feature density on the mask, with the flare variation affecting contrast in the image plane and, thus, minimum feature resolution. The addition of superfluous phase and amplitude features to the mask can be used to control this.
[0012] Although the concept of a phase shifting mask can be directly extended to EUV lithography, the existing technologies for making DUV phase shifting masks are not compatible with EUV mask technology. An EUV mask consists of a thick opaque substrate coated with a reflective multilayer film, on top of which is deposited an absorption layer. The absorption layer is patterned to produce regions that either allow or block reflections from the underlying multilayer coating. This is fundamentally different from the transmissive masks currently used in DUV lithography, and the technology for producing phase shifts in the DUV masks cannot be directly applied to reflective EUV masks.
[0013] The development of a new technology for the production of EUV phase shifting masks, such as the technique described in this ROI, would enable direct application of these existing image enhancement techniques to EUV lithography and would find direct application to the printing of smaller CD features using EUV optical systems.
[0014] Existing Technologies
[0015] With the potential need for phase shifting masks in EUV lithography, several strategies have already been developed for the production of EUV phase shifting masks. These basically fall into three categories: (a) introducing thickness variations by patterning the substrate prior to multilayer coating; (b) depositing phase shifting material on top of the multilayer during the patterning process, and (c) and etching the multilayer to introduce a refractive phase shift into the reflected light.
[0016] The first, illustrated in FIG. 1, involves patterning the substrate 10 prior to multilayer coating 12 with an additional layer 14 of well-controlled thickness. Patrick Naulleau et al, LBL, personal communication, October 2001. The multilayer deposited on this raised region of the substrate will reflect at a different phase as compared to the multilayers on the substrate itself, thereby forming a phase shift between the two parts of the pattern. A major drawback of this technique is that it requires patterning of the mask blank prior to deposition of the reflective multilayer, which would require the multilayer coating infrastructure to be incorporated into the patterning process line. This is at odds with the aim of semiconductor manufacturers to source unpatterned, multilayer coated mask blanks form external vendors. Furthermore, the smoothing process which takes place during multilayer deposition, and which is used to reduce the printability of substrate defects, would make the manufacture of sharp phase gradients and phase discontinuities difficult.
[0017] The second technique, illustrated in FIG. 2, involves depositing additional material 20 , in addition to the absorber material 24 on top of the multilayer stack 22 (on substrate 26 ) to impart a refractive phase shift on the reflected light. See, for example, Czech et al., “Lithography method and lithography mask”, U.S. Patent Application US2001/0021475, 2001, p.2. This is analogous to the addition of more glass in transmissive optics to impart a phase shift into the transmitted light. The problem is that at EUV wavelengths the optical constants are not as forgiving as for visible light For example, a 43 nm thick layer of Molybdenum will impart a λ phase shift on reflected 13.4 nm light, but will also reduce the reflected intensity by a factor of 0.6. Such localized loss of intensity associated with the production of the phase shift is not good when the aim is to produce a purely phase shifting mask, and could cause serious limitations on the practical utility of this approach to phase shifting.
[0018] A third technique, illustrated in FIG. 3, involves thinning ( 30 ) the multilayer 32 (on substrate 34 ) in order to impart the desired phase shift The multilayer stack also includes an absorber layer 36 . This technique draws on ideas developed for the repair of amplitude defects in which it was shown that milling out craters in a reflective EUV multilayer imparts a refractive phase shift on the reflected light given by 2(2π/λ(1−n)h(x), where h(x) is the depth profile of the thinned out region, n is the refractive index difference between the media and the additional factor of two is due to reflection causing the light to pass twice through the region of refractive index change. Note that this phase shift is not the same as the phase shift imparted by reflection from the surface of the lowered profile, which would be given by 4πh(x)/π. This is because the interference properties of the multilayer mirror force all wavefronts within the multilayer to be in phase, thus the phase shift imparted on reflection is due solely to refractive effects and not reflection from the top layer of the thinned region. For Mo/Si multilayers, (1−n)=0.03, so for normal incidence it would be necessary to remove 15 bilayers of material to achieve a phase shift of π in the reflected light. If there are sufficient bilayers in the multilayer before thinning takes place, this reduction in the number of layers will have little effect on the reflected intensity (subject of course to the terminating material, for example Mo rather than Si, not having absorption properties of its own). However there are significant problems with this idea:
[0019] 1. The phase shifting features would be high aspect ratio trenches. Take the case of dense 1:1 features having a minimum feature size of 20 nm at the wafer. For a 4× magnification optical system the feature size on the mask would be 80 nm. The phase shifting trenches would be etched between every other feature, and would need to be less than 80 nm wide and 100 nm deep. This would be difficult to achieve cleanly in the multilayer without damaging the layers or getting undesired edge effects from the finite resolution of the ion mill.
[0020] 2. The interaction of the radiation with the phase shifting features would be complicated, and would certainly include some diffraction from the side walls. This could lead to undesirable modulations of the aerial image that would be difficult to control.
SUMMARY OF THE INVENTION
[0021] It is an object of the present invention to phase shifting mask and a method for fabricating a phase shifting mask for EUV lithography.
[0022] It is another object to enhance the printability of a reflection mask consisting of a patterned absorber layer deposited on a reflective multilayer coating.
[0023] These and other objects will be apparent based on the disclosure herein.
[0024] The invention is a phase shifting mask and a method for fabricating a phase shifting mask for EUV lithography. The principle is to enhance the printability of a reflection mask consisting of a patterned absorber layer deposited on a reflective multilayer coating by producing a phase shift between the fields reflected on either side of a critical feature, as shown in FIG. 4. A multilayer stack 40 on a substrate 42 includes a patterned absorber layer 44 . Layer contraction is produced, e.g., at 46 by localized heating.
[0025] The strategy of applying a pi phase shift across a critical feature reduces k 1 and extends the resolution of the imaging process well beyond the Raleigh diffraction limit. Other potential advantages derived from using the phase shift strategy include (1) reducing the required numerical aperture, which increases the depth of focus and decreases the manufacturing cost of the optical system, and (2) increasing the NILS of the aerial image, which increases the process latitude and makes the exposure less sensitive to flare. However, the methods used to produce phase shifting masks in DUV lithography do not readily extend to EUV lithography due to the fundamental change from the transmission to the reflection mode of operation. This invention consists of a process for producing a spatially varying phase shift in a EUV mask by locally modifying the structure of the reflective multilayer coating. The multilayer structure is modified by exposing the mask to a high-resolution thermal source such as an electron beam. The energetic beam causes thermally activated interdiffusion in the reflective multilayer coating, producing a contraction of the layers that results in a local phase shift with no appreciable loss of reflectivity. This process can be applied to the mask as a last step, after the patterning of the absorber layer, which has the advantage of being able to use the absorber pattern for alignment
BRIEF DESCRIPTION OF THE DRAWINGS
[0026] [0026]FIG. 1 shows the prior art patterning of a substrate prior to multilayer coating.
[0027] [0027]FIG. 2 shows the prior art deposition of additional material on top of the multilayer stack to impart a refractive phase shift on the reflected light.
[0028] [0028]FIG. 3 shows the prior art technique of thinning a multilayer in order to impart a desired phase shift.
[0029] [0029]FIG. 4 illustrates the phase shift technique of the present invention, in which localized heating is used to induce local contraction in the multilayer period, resulting in a phase shift in the reflected light.
[0030] [0030]FIG. 5 shows a schematic representation of the production of the arbitrary phase patterns using a high-resolution electron beam to heat the multilayer to activate silicide formation at the Molybdenum/Silicon multilayer interfaces.
[0031] [0031]FIG. 6 shows a simulation of the multilayer contraction resulting from a 35 ms exposure to an electron beam of r o =150 nA at 10 kV.
[0032] [0032]FIG. 7 is an example of the surface profile modification caused by electron beam heating.
DETAILED DESCRIPTION OF THE INVENTION
[0033] The invention described herein is compatible with the manufacture of phase shifting reflective EUV masks in which all steps can be accomplished as a part of the patterning process. U.S. patent application Ser. No. 09/669,390, filed Oct. 26, 2000, titled “Repair Of Localized Defects In Multilayer-Coated Reticle Blanks For Extreme Ultraviolet Lithography” is incorporated herein by reference. U.S. patent application Ser. No. 09/752,887, titled “A Method For Fabricating Reticles For EUV Lithography Without The Use Of A Patterned Absorber” is incorporated herein by reference.
[0034] Embodiments of the present invention specifically contemplate the use of this technique on Mo/Si multilayers in which the heating is caused by a focused, energetic electron beam. However, the technique could be applied to multilayers made of other material, in which case the layer contraction described here could take the form of expansion. Furthermore, although the following description is directed to the use of an electron beam for the heating, it should be pointed out that the technique relies only on the heating, and the use of other heat sources to write the phase pattern might be possible. For the purposes of simplicity, however, consider the specific example of a Mo/Si multilayer heated using a focused electron beam. This serves to make the discussion more directed and enables the use of concrete examples to describe the technique.
[0035] The present method, as illustrated schematically in FIG. 5, contemplates the production of the arbitrary phase patterns using a high-resolution electron beam 50 to heat the multilayer 52 (on substrate 54 ) to activate silicide formation at the Molybdenum/Silicon multilayer interfaces. Because the silicide layer is denser than either Mo or Si alone, growth of the silicide leads to contraction of the multilayer in the regions where the silicide has been formed, and this contraction in turn alters the position of the reflective layers within the multilayer. The phase of the reflected light is determined by the location of the Mo layers, thus displacing one part of the multilayer relative to another causes a shift in the relative phase shift of the reflected light. In the case of defect repair, this contraction is used to restore the phase of the distorted multilayer to reduce the defect printability; conversely, the same strategy can be used to induce a deliberate phase shift in the reflected light in order to produce printable features. That is to say, the phase shifting properties of layer contraction can be used to produce a programmable phase pattern in the reflected light. As shown in the figure, a point beam produces a dot and a scanned beam produces a line or area phase shifts. The beam is scanned in the direction 56 .
[0036] Silicide growth at the Mo/Si interfaces is essentially an activated process limited by thermal interdiffusion. See R. S. Rosen et al., (1993) 32 Appl. Opt. 6975.
[0037] Silicide growth is understood and can be modeled as following the relationship
w 2 =w o 2 +2 Dt
[0038] where w o =1.0 nm is the starting thickness of the MoSi 2 interface layers in deposited Mo/Si multilayers and the interdiffusion coefficient is given by
D=D
o
e
−E
a
/kT
[0039] where D o =50 cm 2 /S and E A =2.4 eV for multilayer films. The formation of the silicide leads to densification, which in turn causes contraction of the multilayer period. That change in period is given by
εΛ=Λ o −α( w−w o )
[0040] where α=0.39 is the contraction factor, the value of which depends on the particular silicide compound formed. See D. G. Stearns, “High-Performance Multilayer Mirror For Soft X-Ray Projection Lithography”, Proc. Soc. Photo-Opt. Instrum. Eng., San Diego, 1991, p.2.
[0041] It can be seen from these equations that the silicide layer growth has an approximately square root dependence on the time the multilayer is subjected to heating, which is herein referred to as the exposure time. For a given electron beam, it is possible to model the energy deposition and, thus, the heating caused in the sample. From this it is relatively straightforward to compute the rate of silicide formation using the above equations and from that, compute the layer contraction profile. Given that the heating time and/or strength can be readily controlled, it is therefore possible to controllably deform the multilayers and, hence, write arbitrary phase patterns directly into the multilayer film.
[0042] For example, FIG. 6 shows a simulation of the multilayer contraction resulting from a 35 ms exposure to an electron beam of r o =150 nA at 10 kV. Note that the top-layer depression is 6 nm, but that this depression is distributed over a number of layers so that the maximum individual layer contraction is εΛ=0.2 nm. This assures that the repair affects primarily the phase of the reflected field whilst not adversely affecting the reflectance curve. Note, however, that there is no practical limit to the scale over which the phase shift may be affected, thus it is possible to produce large phase shifted regions if necessary. This could be achieved by either scanning a small beam over the sample to write a pattern, or by using a larger electron beam to heat more of the sample. At the other end of the scale, the smallest feature size that could be written is determined by restrictions on electron beam spot size and current imposed by the physics of electron beam interactions in column design.
[0043] An example of the surface profile modification caused by electron beam heating is shown in FIG. 7. In this case a multilayer consisting of 40 bilayer pairs of alternating Mo and Si with a bilayer period of 7.0 nm was deposited on a 1″×¼″ fused silica substrate, and then irradiated with 12 keV electrons at a beam current of 0.8 mA in a beam radius of 500 μm e −2 radius. To vary the dose, the electron beam was scanned at various scan speeds and the resultant multilayer profile observed. The results of this experiment are shown in FIG. 7. A clean trench was formed by the electron beam and the depression depth was readily controlled by varying the dose (in this case the scan speed).
[0044] As described above the strategy of the repair is to use the layer contraction induced by the local heating to cause a depression in the multilayer. However, it is evident from inspection of FIG. 6 that the electron beam heating does not produce a uniform displacement throughout the film—the layer displacement increases with depth from the surface. Hence, the desired profile is produced at a single chosen depth; the layers above this will have slightly more displacement and the layers below will have slightly less. As the goal is to produce a desired phase structure, the depth at which the amplitude of the reflected field is divided into two equal parts is chosen as the depth at which to effect the desired layer profile. The reflected field from the layers above this depth will have slightly retarded phase whilst the field from the layers below will have slightly advanced phase, and the contribution from the two will, on average, cancel out in the total reflected field. The actual depth of this layer is chosen by considering the number of layers required to obtain half the reflected amplitude (one quarter of the reflected intensity) of the entire multilayer coating. For Mo/Si multilayers this turns out to be the 7 th bilayer from the top surface, thus we choose to make the 7 th layer have the depression profile necessary to produce the desired phase structure.
[0045] It is also necessary to consider the effect of layer contraction on the multilayer reflectance curve to ensure that the multilayer reflectivity is not moved too far out from the bandpass of the optics. To investigate this, the reflectance profile of the phase-shifted multilayers was measured and is shown in FIG. 7. The multilayer contraction does cause a slight shift in the wavelength as expected, and also causes a slight decrease in reflectivity associated with the formation of additional MoSi 2 at the multilayer interfaces.
[0046] In viewing this data is must be remembered that change in the reflectance curve, as measured by the wavelength at which the reflectivity peaks, is a direct consequence of the individual layer contraction, and that the individual layer contraction required to produce a given phase shift will decrease as the number of layers contracted increases. Given that most of the reflection occurs within the top few layers the amount of wavelength shift could therefore be reduced by increasing the number of bilayers participating in the contraction. Modeling of electron beam heating at energies of 12-16 kV indicates that the majority of the heating, and therefore the majority of layer contraction, will take place within the top 20 bilayers. However if a heat source can be found which could provide more uniform heating through the depth of the multilayer, the amount of wavelength shift could be reduced—the greater the number of layers participating in the contraction the smaller the shift in peak reflectivity caused by introducing a given phase shift.
[0047] Note also that phase shift masks in which the phase shifting material introduces some attenuation are not new to the field. See, for example, U.S. Pat. No. 5,928,281, titled “Attenuated Phase Shift mask”, Krivokapic et. al., issued 1999. Thus, there are existing technologies that can handle or compensate for the effect of attenuation that might be introduced into the phase shifted regions.
[0048] The present invention is not limited to electron beam heating. The layer contraction effect can be produced by any form of localized heating. The example of electron beam heating is an example of an embodiment of the technique. Other embodiments can be carried out using, e.g., an electromagnetic beam or an ion beam The scope of the claims is limited to any one type of phase shifting mask (for example the alternating phase shift mask, commonly referred to as alt-PSM). The technique can be used to produce controllable phase structures on masks for any purpose and is not limited to any one particular embodiment of phase shift mask technology.
[0049] The foregoing description of the invention has been presented for purposes of illustration and description and 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. The embodiments disclosed were meant only to explain the principles of the invention and its practical application to thereby enable others skilled in the art to best use the invention in various embodiments and with various modifications suited to the particular use contemplated. The scope of the invention is to be defined by the following claims. | A method for fabricating an EUV phase shift mask is provided that includes a substrate upon which is deposited a thin film multilayer coating that has a complex-valued reflectance. An absorber layer or a buffer layer is attached onto the thin film multilayer, and the thickness of the thin film multilayer coating is altered to introduce a direct modulation in the complex-valued reflectance to produce phase shifting features. | 6 |
BACKGROUND OF THE INVENTION
The present invention relates to a hairspring for a balance wheel/hairspring resonator.
DESCRIPTION OF THE PRIOR ART
It is known that the center of gravity of a flat hairspring moves during the oscillatory movement of the balance wheel. This is due to the fact that one of the ends of the hairspring is fixed, whereas the other end moves while still remaining at the same distance from the balance wheel arbor. This displacement of the center of gravity has an influence on the isochronism because it generates lateral forces on the pivots of the balance wheel arbor.
Abraham-Louis Breguet had the idea of providing the flat hairspring with one or two terminal curves enabling this defect to be remedied. Subsequently, a theoretical treatment of such a curve was published by M. Phillips.
Before the solution devised by Breguet and Phillips, T. Mudge had proposed the use of two hairsprings fastened to the same balance wheel and offset by 180°. Since the hairsprings work in synchronism, but in phase opposition, the variations in their respective centers of gravity are compensated for, but their axial offset creates, however, a slight torque in a plane containing the balance wheel arbor. This solution has been adopted in recent productions.
The problem with this solution lies in the fact that it is necessary to have two superposed hairsprings, increasing the height, two studs and two stud carriers that are offset by 180° about the balance wheel arbor, and two regulator pins, and each hairspring must be regulated in perfect synchronism with the other, leading to an extremely complex solution difficult to implement. In addition, it doubles the number of components.
This solution has been adopted in several publications, especially in U.S. Pat. No. 3,553,956, in FR 2 447 571 and in CN 1 677 283.
The object of the present invention is to benefit from the advantages of this solution while remedying, at least in part, the abovementioned drawbacks.
SUMMARY OF THE INVENTION
For this purpose, the subject of the present invention is a hairspring for a balance wheel/hairspring resonator, which hairspring comprises n blades, where n≧2, fastened via at least one of their respective homologous ends are wound in spirals with an angular offset capable of neutralizing the lateral forces likely to be exerted on its central arbor when one of the ends of each blade is moved angularly about said central arbor relative to its other end.
BRIEF DESCRIPTION OF THE DRAWINGS
The appended drawings illustrate schematically, and by way of example, several embodiments of the hairspring forming the subject of the present invention:
FIG. 1 is a plan view of a first embodiment;
FIG. 2 is a plan view of a second embodiment;
FIG. 3 is a graph showing the variation of the hairspring pitch plotted as a function of the number of turns from the center outwards in the case of the embodiment shown in FIG. 2 ;
FIG. 4 is a graph showing the variation in the thickness along the blade plotted as a function of the number of turns from the center outwards in the case of the embodiment shown in FIG. 2 ;
FIG. 5 is a plan view of a third embodiment;
FIG. 6 is a plan view of a fourth embodiment;
FIG. 7 is a plan view of a fifth embodiment;
FIG. 8 is a plan view of a sixth embodiment;
FIG. 9 is a side view of a seventh embodiment;
FIGS. 10 a and 10 b are side views of two variants of an eighth embodiment; and
FIG. 11 is a side view of a ninth embodiment.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The first embodiment of the hairspring forming the subject of the invention is illustrated in FIG. 1 . This flat hairspring comprises two blades 1 a, 1 b wound in the same direction, but with an offset of 2π/2, i.e. 180°. The respective internal ends of these blades 1 a, 1 b are fastened to a collet 2 and their external ends are fastened to a fastening ring 3 . These external ends are also angularly offset by 180°. The fastening ring 3 to which the external ends of the blades 1 a, 1 b of the hairspring are fastened has an opening 3 a for fastening it to the balance wheel bridge. This fastening ring 3 therefore replaces the conventional stud.
The two blades 1 a, 1 b of the hairspring must not touch each other as they contract and expand. The risk of so doing increases with the amplitude. Therefore, this can be reduced by limiting the amplitude. However, it may be also advantageous to increase the diameter of the hairspring.
Yet another solution is that which consists in varying the pitch of the turns and varying the thickness of the blades. This is shown by the embodiment in FIG. 2 , and also the graphs of FIGS. 3 and 4 which illustrate the variation in the pitch of the turns in microns and the variation in the thickness of the blades in microns, respectively, as a function of the number of turns N t of the wound blades 1 a, 1 b of FIG. 2 , starting from the center of the hairspring toward the outside, so as to prevent the turns of the blades 1 a, 1 b from touching each other during the alternating expansion and contraction of the hairspring. FIG. 3 plots one of the two blades 1 a, 1 b through the formula r(θ)=r 0 +p(θ)×θ/2π, where r represents the distance from the arbor to the neutral fiber of the blade and r(θ=0)=r 0 =600 microns in the case of FIGS. 2 to 4 and θ=2πN t .
As a variant, the height of the hairspring blade could also be varied.
In the case of hairsprings made of single-crystal silicon, a material that can be used to produce the hairspring according to the invention, the temperature compensation of the hairspring is achieved by forming, on the surface of the hairspring blades, a layer of amorphous silicon oxide, the thermal coefficient of the Young's modulus of which is of opposite sign to that of single-crystal silicon, as described in EP 1 422 436. This amorphous silicon oxide layer makes it possible to compensate for the thermal coefficient of the Young's modulus whatever the crystallographic orientation of the silicon, namely (100), (111) or (110).
The number of blades forming the hairspring is not limited to two. As a variant, various other solutions may be envisioned, such as that illustrated in FIG. 5 , which is a variant of that of FIG. 1 , but which has three blades 1 a, 1 b and 1 c attached, on the one hand, to the collet 2 and, on the other hand, to the fastening ring 3 . The internal and external ends of these blades are angularly offset with respect to one another by an angle of 2π/3. This angular offset will advantageously be 2π/n, where n corresponds to the number of blades.
Simulations carried out based on the hairsprings of FIGS. 1 and 2 have shown that it ought to be possible for the isochronism of a balance wheel/hairspring resonator fitted with a hairspring according to the present invention to be very substantially improved.
In the embodiments described hitherto, the blades forming the hairspring are attached to one another via their two respective ends. The embodiment illustrated in FIG. 6 shows a hairspring formed from two blades 1 a, 1 b attached via only their internal ends to the collet 2 . Their external ends are free, thereby making it possible to pretension the two blades, in one direction or another, so as in particular to adjust the isochronism.
Other variants using the same concept, namely a hairspring having several angularly offset coplanar blades attached via at least one of their respective homologous ends, can be envisioned.
Thus, it is possible to have a hairspring comprising four blades, namely two blades 1 a, 1 b placed between the collet 2 and an intermediate ring 4 , to which their external ends are fastened, and two blades 1 c, 1 d placed between the intermediate ring and the fastening ring 3 . To make the intermediate ring 4 as light as possible, its structure may be apertured so as to reduce its weight as far as possible.
The internal blades 1 a, 1 b and the external blades 1 c, 1 d may all be wound in the same direction, as illustrated in FIG. 7 , or the internal blades 1 a, 1 b may be wound in the opposite direction to that of the external blades 1 c, 1 d, as illustrated in FIG. 8 .
It is obvious that countless other combinations may be envisioned.
It is also obvious that the novel design of the hairspring according to the invention does not lend itself to being manufactured using the conventional processes for Nivarox/Parachrom hairsprings.
In the present case, a process very suitable for the manufacture of the hairspring according to the invention is in particular the one described in EP 1 422 436, already mentioned, which consists in cutting the hairspring, for example by plasma etching, from an {001} single-crystal silicon wafer. The hairspring is temperature-compensated by the formation of a layer of amorphous silicon oxide on the surface of the hairspring blades, for example by a heat treatment.
It would also be possible to use a quartz single crystal machined in the same way or by chemical machining. Other appropriate materials, adapted to the embodiments for producing a hairspring in a plane, can be used.
The use of photolithographic processes, such as the UV-LIGA (Lithographie, Galvanisierung und Abformung) process, could also be used to produce this type of hairspring according to the present invention made of a metal alloy.
The manufacturing process does not form part of the present invention. The nonlimiting examples of processes, listed above by way of example, are merely intended to demonstrate that the technical means for producing the novel type of hairspring according to the invention already exist and that a person skilled in the art has a raft of options for producing this hairspring.
When the hairspring is referred to as being flat, this is the hairspring as obtained above. However, nothing precludes locating the embedment points 5 and 6 of the external ends of the blades 1 a, 1 b outside the plane of the hairspring, especially on one side of the balance wheel 7 in the embodiment shown in FIG. 9 . Thus, these two embedment points may be respectively located on either side of the plane of the hairspring, so that the two blades 1 a, 1 b form two symmetrical cones on either side of the plane of the hairspring. This solution has the advantage of preventing the turns of the two blades from touching each other and makes it possible to produce hairsprings of small diameter with a large number of turns. Such a solution therefore constitutes another means of preventing contact between the blades of the hairspring during the alternation of expansions and contractions.
According to another variant of the invention, the two blades 1 a, 1 b are made on an SOI (Silicon-On-Insulator) wafer as shown in FIGS. 10 a, 10 b, which consists of an Si—SiO 2 —Si multilayer stack. A blade 1 a is etched from the external face of one of the Si layers and the other blade 1 b is etched from the external face of the second Si layer. In this case, the internal ends of the two blades are fastened via the intermediate SiO 2 layer 8 . The advantage of this embodiment is that it reduces the diameter of the hairspring, as the distance between two adjacent turns is increased. Such an advantage is even more pronounced if the hairspring is extended vertically, as shown in FIG. 10 .
FIG. 11 illustrates another variant of FIGS. 10 a , 10 b in which the internal ends of the blades 1 a, 1 b are fastened to the same collet 8 , whereas their external ends are fastened to the SiO 2 intermediate layer 5 . | Hairspring for a balance wheel/hairspring resonator, comprising n blades, where n≧2, which are fastened via at least one of their respective homologous ends and wound in spirals with an angular offset capable of neutralizing the lateral forces liable to be exerted on its central arbor when one of the ends of each blade is moved angularly around said central arbor relative to its other end. | 6 |
CROSS-REFERENCE
[0001] This application is a continuation-in-part application of Ser. No.14/622,114, filed Feb. 13, 2015, which is a continuation of Ser. No. 12/628,382, filed Dec. 1, 2009 and now issued as U.S. Pat. No. 8,986,291 on Mar. 24, 2015, which claims the benefit of Provisional Application No. 61/118,802, filed Dec. 1, 2008, and Provisional Application No. 61/170,055, filed on Apr. 16, 2009, the disclosures of which are incorporated herein by reference in their entirety.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates generally to medical apparatus and methods. More particularly, the present invention relates to a method and apparatus for capturing, fragmenting, and removing urinary stones from the kidney or bladder as well as capturing, dissecting or incising, and removing from the interior of a kidney or bladder, or other body lumen.
[0004] Urinary tract endoscopy, a minimally invasive procedure for removing urinary stones, debulking growths and tumor, and collecting biopsy samples that are present in the bladder, ureter, or kidney, may be performed in several ways. A large viewing scope, referred to as a cystoscope, is advanced from the urethra into the bladder. When necessary, a smaller ureteroscope is further advanced from the bladder, through the ureter, and into the kidney. Alternatively, a nephroscope entering through a percutaneous tract into the kidney may be used in the kidney and upper urinary tract. In each of these protocols, endoscopes carry either an optical element or optical fiber bundle which in some cases is steerable so that individual stones or targeted tissue may be observed, captured, and removed from the kidney and bladder. Similarly, other types of endoscopes such as gastroscopes or colonoscopes are utilized for similar purposes in non-urinary body tracts or lumens. The endoscopes carry a working channel for the introduction of tools to the distal end of the device. The working channel in a smaller endoscope such as a ureteroscope or angioscope, however, has have a very small diameter, due to the very small size of the device itself, typically limiting tool use to one small tool at a time. Optionally, the stones or tissue may be fragmented using laser or other energy, and the intact stone and/or fragments may be removed using a deployable basket advanced through a working channel of the endoscope, while large or multiple tissue samples too large to be withdrawn through the working channel are managed similarly using baskets or grasping devices. In both cases, the entire endoscope must be withdrawn, along with the samples or fragments to in order to retrieve those for further study. This can require multiple placements and removals of the endoscope, extending the procedure duration as well as potentially increasing endoscopic-related trauma to the patient.
[0005] Endoscopic stone treatment is particularly difficult to perform in the bladder and kidney where the stones or stone fragments may be mobile and are present in a large open volume and thus are often difficult to capture. While the stones may be captured using a basket or other tools under direct visualization, steering the scope and firmly capturing the stone is problematic, particularly if the stone is mobile and suspended within the open volume. Moreover, if the stone is fragmented with energy, capturing the many stone fragments which disperse throughout the volume and can be even more difficult and time consuming.
[0006] For these reasons, it would be desirable to provide improved and alternative apparatus and protocols for the ureteroscopic treatment and removal of stones from the urinary system, particularly the kidney and bladder. Such systems and protocols will preferably be compatible with many or all conventional endoscopes which are commercially available. Desirably, the apparatus and protocols will facilitate capturing of the stones within the open volumes of the kidney and bladder, will allow for energy-based fragmentation of the stones while they remain captured, and will contain most or all of the stone fragments resulting from the fragmentation. The apparatus and protocols would preferably reduce the need to use the working channel of the endoscope, making the working channel available for an energy source or use in new protocols.
[0007] Similarly, tumor or growth debulking in a relatively large open volume is inefficient when multiple fragments are removed or also inefficient when multiple biopsy samples are taken due to the desirability of not having to remove the endoscope for each individual sample recovery. Despite the tissue being typically initially anchored to a lumen wall, recovery of loose sample is time consuming and inefficient. Further, in the case of a growth or tumor fully filling a smaller lumen such as the ureter, the target tissue may itself distort or mis-shape the lumen. Preferably the apparatus and protocols will help to correct this distortion and improve the ability of the endoscope to visualize and excise the tissue while aiding the collection and removal.
[0008] At least some of these objectives will be met by the inventions described below.
[0009] 2. Background of the Background Art
[0010] This is a continuation in part of copending application Ser. No. 14/622,144. The present application claims the benefit of Provisional Application No. 61/118,802, filed on Dec. 1, 2008, and Provisional Application No. 61/170,055, filed on Apr. 16, 2009, which are incorporated in U.S. Pat. No 8,986,291. Commonly owned, copending application Ser. Nos. 10/886,886; 11/777,515; 12/041,241; and 12/269,739 describe conformable structures which are deployable in the urethra and ureter and which may be used to entrap stones during lithotripsy. Dr. Bogdan Petrut has filed a Romanian Patent Application describing a stone capture device for attaching to a ureteroscope to capture and draw stones into a sheath for containing the stones while delivering laser energy to break up the stones. See also U.S. Pat. Nos. 3,760,810; 3,870,048; 4,222,308; 4,257,420; 4,471,766; 4,735,194; 5,423,834; 5,507,797; 6,099,535; 6,645,195; 6,869,395; 7,204,804; and 7,223,230. U.S. Patent Publication No. US2006/0116693 describes a stone capture device intended for use in lithotripsy treatment. The RothNet® foreign body retrieval device is described at http://www.usendoscopy.com/foreignbody.php.
SUMMARY OF THE INVENTION
[0011] In a first aspect of the present invention, methods are provided for removing urinary stones or tissue from a body cavity, such as a kidney or, bladder or stomach, or a stone or tissue from a body lumen such as ureter, hepatic duct or colon. The methods comprise introducing a viewing scope, such as a commercially available ureteroscope, having an optical element at its end into an open volume of the body cavity. A perforate sweeping structure is deployed from a distal end of the viewing scope, while the viewing scope is steered and advanced within the open volume of the body cavity to engage the deployed perforate sweeping structure against the stone. Once the stone is engaged, the sweeping structure is further advanced to urge the stone against a wall structure of the body cavity so that the stone is captured between the sweeping structure and the wall structure. Energy is then applied through the viewing scope, typically laser energy delivered via an optical (laser) fiber advanced through a working channel of the viewing scope. The delivered energy disrupts the captured stone and large fragments, producing smaller stone fragments. Usually, the stone is held in place while delivering energy solely by the sweeping structure against the wall structure, and no separate basket, forceps, loop structures, or the like, are used to hold the stone in place. In a preferred aspect of the method, the region around the captured stone is irrigated, typically before, during, and/or after the energy-based fragmentation, to wash the stone fragments into the sweeping structure. Preferred sweeping structures comprise mesh structures, often double-walled mesh structures, in which the stone fragments become entrapped as they are washed away by the irrigating solution.
[0012] The viewing scope is usually introduced transluminally, i.e., through the urethra and optionally through the bladder, ureter, and into the kidney. Alternatively, however, the sweeping structure and viewing scope could be introduced through a percutaneous incision in the abdomen.
[0013] During delivery and prior to deployment, the perforate sweeping structure is usually maintained in a tubular configuration. Such a tubular structure may be deployed by axial foreshortening. The sweeping structure is disposed over a distal portion of the viewing scope, where the tubular configuration is transformed into a concave structure which extends distally from the distal end of the viewing scope. The concave structure, which may be conical, hemispherical, or have other expansibly tapered structures, will surround the optical element of the viewing scope so that view from the element is not obscured. Moreover, the tubular configuration of the sweeping structure will typically be sufficiently flexible so that the distal end or region of the viewing scope can be steered in a conventional manner without excessive constraint by the sweeping structure. When the tubular configuration of the sweeping structure is shifted to the concave structure, however, it will become more rigid, allowing it to engage, move, and entrap kidney stones against the body cavity wall while retaining sufficient flexibility to conform to an irregularly shaped wall surface. While a preferred perforate sweeping structure is deployed by foreshortening, alternative sweeping structures may have an initial collapsed, closed configuration extending over the distal end of the viewing structure and may be deployed or otherwise opened to a concave configuration surrounding the distal end of the viewing structure, typically by releasing the constrained structure from a surrounding sleeve or other structure.
[0014] The methods of the present invention optionally include steering the viewing scope within the body cavity while the distal portion of the viewing scope is present within the tubular configuration of the sweeping structure. Methods further comprise engaging the perforate structure against the urinary stones when said structure is sufficiently rigid to manipulate the stones while remaining sufficiently flexible to conform an outer rim of the structure to an irregularly shaped bladder wall and sufficiently porous to allow fluids to pass freely through the perforations or apertures in the perforate structure when the region is being irrigated. Generally, the perforate sweeping structure will be formed as a metal or polymeric mesh with individual interwoven wires or filaments. The mesh will have openings or interstices which are sufficiently large to allow the free flow of irrigation fluid, but which have dimensions which contain and/or entrap the stone fragments within the mesh, particularly within a double walled mesh structure which will be described hereinbelow. Usually, porosity of the deployed perforate structure will be sufficient to limit stones larger than 2 mm in any dimension from passing therethrough. The deployed perforate structure utilizes irrigation from the viewing scope to maintain the captured stone fragments (typically smaller than 2 mm) against the interior of the perforate structure and/or against the wall of the body cavity so as not to obscure vision during lithotripsy procedures.
[0015] Usually, the perforate sweeping structure will be removably attached to the distal end of the viewing scope. Thus, after the assembly viewing scope and perforate structure has been used in a procedure, the perforate sweeping structure may be detached from the assembly and disposed of while the viewing scope may be sterilized and reused.
[0016] While the presently preferred perforate sweeping structure will be an evertable tubular structure, as described above, other embodiments of the perforate sweeping structure include a self-expanding tube or other elongate structure which can be distally advanced from a carrier sleeve or sheath. Usually, the carrier sleeve or sheath will be configured as a “monorail” device which has a relatively short engagement length, typically from 2 cm to 10 cm, usually from 3 cm to 8 cm, with a lumen or passage therethrough which receives the viewing scope. Thus, the carrier sleeve may be advanced over a proximal end of the viewing scope in a manner similar to a monorail vascular catheter. A hypotube or other elongate shaft is attached at the proximal end of the carrier sleeve allowing the carrier sleeve to be pushed over the viewing scope until the sleeve reaches the distal end of the scope. At that point, a second pusher rod or element is used to distally advance a conical (tapered to open in the distal direction) or other expanding mesh structure from the carrier sleeve, where the structure will be configured so that a proximal end is aligned with the optical viewing element of the viewing scope. The assembly of the viewing scope and the carrier sleeve with deployed perforate sweeping structure then can be manipulated and advanced within the open volume of the body cavity to capture stones and engage the stones against a structure, typically a wall of the body lumen, prior to delivering energy to break up the stones. After the stones are broken up, the perforate structure may be proximally retracted so that the structure as well as the stones carried therein are drawn back into the carrier sleeve which may then be withdrawn from the body cavity to remove the stone fragments.
[0017] In a second aspect of the present invention, a stone capture device for use with a steerable viewing scope comprises a sheath and a perforate sweeping structure. The sheath has a distal end, a proximal end, and a lumen therebetween, where the lumen is positionable over the distal end of the viewing scope. Usually, the sheath will have a length which extends over most, but not all of the length of the viewing structure, allowing a proximal end of the sheath to be available for manipulation by the treating physician during a procedure. That is, the sheath will have a length sufficient to allow the proximal end of the sheath to lie outside of the patient even when the distal end has been fully advanced into the kidney. Usually, the sheath length will be in the range from 20 cm to 100 cm, more usually from 60 cm to 70 cm when configured for use with a relatively long ureteroscope, and will be in the range from 10 cm to 50 cm, usually from 30 cm to 35 cm when configured to work with a shorter cystoscope or nephroscope.
[0018] The perforate sweeping structure will be removably attached to and extend distally from the distal end of the sheath. The perforate sweeping structure will be shiftable between a tubular configuration with a width generally about the same as that of the sheath and a concave configuration which increases in width in the distal direction. A distal end of the viewing scope is disposed within the concave sweeping structure when said sweeping structure is deployed. Prior to deployment, the sweeping structure may be positioned proximally to the distal end of the viewing scope to enhance visibility and/or maneuverability of the distal scope tip. Usually, an optical element of the viewing scope will be generally centered within the deployed sweeping structure. Optionally, the stone capture device may further comprise a means for closing a distal end of the deployed concave sweeping structure to capture the stones therein. Conveniently, the closing means may be a simple wire, suture, or other loop or tether which extends around the distal end of the deployed concave sweeping structure. Thus, the tether can be drawn to close the distal end in the manner of a “purse string.” The sweeping structure typically comprises woven or braided filaments which form a mesh tube which can be foreshortened to evert to form a double-walled concave structure. The double-walled concave structure will usually have a conical or hemispherical geometry, typically being advanceable over the viewing scope, typically in a monorail fashion, the position the sweeping structure in the bladder or kidney.
[0019] In a preferred configuration where the perforate sweeping structure is attached to the distal end of the viewing scope, the sheath will typically be configured to position the perforate sweeping structure distally over a distal region of the viewing scope while the sweeping structure is in its tubular configuration. By drawing the viewing scope proximally, where the viewing scope is connected to a distal end of the tubular sweeping structure, the tubular configuration of the sweeping structure will be deformed to assume a concave configuration where all or a principal portion of the concave configuration is positioned distally of the distal end of the viewing structure. In its tubular configuration, the sweeping structure will be sufficiently flexible and bendable to allow steering of the viewing structure within the sweeping structure prior to deployment. After deployment into its concave configuration, however, the sweeping structure will assume its double-walled configuration and will have sufficient stiffness to engage and manipulate stones within the body cavity so that the stones may be urged against a cavity wall. Typically, the sweeping structure in its concave configuration will have a bending stiffness which is at least 25% greater than that in the tubular configuration, usually being at least 50% greater, and often being 100% greater or more. The sweeping structure in its concave configuration will further have a width which is greater than that of the sheath, typically being at least twice that of the sheath, often up to eight-fold larger that the sheath width.
[0020] The stone capture device is typically packaged as a kit where the sheath and perforate sweeping structure are attached to each other, sterilized, and present in a sterile package, such as a bag, tube, or box. The stone capture device is thus ready to be removably attached to the distal end of a conventional or commercially available viewing scope, such as a ureteroscope, where a distal portion of the scope is placed within the perforate sweeping structure of the capture device. The distal end of the scope will typically be secured to the distal tip of the tubular configuration of the perforate sweeping structure so that retraction of the viewing scope relative to the sheath will foreshorten the perforate sweeping structure causing it to assume the concave configuration.
[0021] Similarly, the same device structure may be utilized in other open lumens of the body such as the stomach or peritoneum for management of tissue removed from the body for the purposes of debulking a cancerous or non-cancerous growth or for collection of multiple or large biopsy samples.
[0022] In a final aspect, the same device structure may be utilized to expand and to circularize a body duct distorted by a stone or a growth in order to achieve better visualization and access for a debulking or biopsy procedure. In this case, the user would manipulate the endoscope until it was immediately adjacent to the restriction, then evert or expand the porous collection cone of the above device in order to correct the distortion caused by the restriction itself. In some cases, the deployment of the cone will simultaneously slightly expand the duct immediately adjacent to the restriction. Increased visualization, due to the expanded space, as well as the increased irrigation flow allowed through the porous cone improves visualization, particularly if the excision or biopsy process causes bleeding. A relatively large quantity of tissue may be removed in a single endoscopic placement by filling the cone before endoscope removal.
INCORPORATION BY REFERENCE
[0023] All publications, patents, and patent applications mentioned in this specification are herein incorporated by reference to the same extent as if each individual publication, patent, or patent application was specifically and individually indicated to be incorporated by reference.
BRIEF DESCRIPTION OF THE DRAWINGS
[0024] The novel features of the invention are set forth with particularity in the appended claims. A better understanding of the features and advantages of the present invention will be obtained by reference to the following detailed description that sets forth illustrative embodiments, in which the principles of the invention are utilized, and the accompanying drawings of which:
[0025] FIG. 1 is a perspective view of a stone capture device constructed in accordance with the principles of the present invention.
[0026] FIG. 2 is a perspective view of a viewing scope in the form of a commercially available ureteroscope having a steerable distal end.
[0027] FIG. 3 is a detailed view of the distal end of the stone capture device of the present invention.
[0028] FIGS. 4A and 4B illustrate the distal end of the stone capture device with a partially deployed sweeping structure.
[0029] FIGS. 5A and 5B illustrate the distal end of the stone capture device with a fully deployed sweeping structure.
[0030] FIG. 6 illustrates the initial placement of the stone capture device and viewing scope of the present invention through the urinary tract into a kidney.
[0031] FIGS. 7A-7D illustrate deployment of the sweeping structure on the stone capture device for capturing, fragmenting, and removing a stone within the kidney.
[0032] FIGS. 8A-8C illustrate the structure and use of an alternative embodiment of the sweeping structure of the present invention.
[0033] FIG. 9 illustrates the use of the stone capture device in a bladder.
[0034] FIGS. 10A-10B illustrates the use of the stone capture device in a duct or vessel.
DETAILED DESCRIPTION OF THE INVENTION
[0035] Referring to FIG. 1 , a stone capture device 10 constructed in accordance with the principles of the present invention comprises a sheath 12 having a proximal end 14 and a distal end 16 . A deployable sweeping structure 18 is disposed at the distal end of the sheath 12 and is shiftable between a low profile tubular configuration (shown in full line) and an open or deployed concave configuration (shown in broken line). A hub 20 is typically provided at the proximal end 14 of the sheath 12 .
[0036] The stone capture device 10 of the present invention is intended to be mounted over the steerable shaft 24 of a conventional viewing scope ( 26 , FIG. 2 ), typically a ureteroscope, such as those commercially available from Olympus/ACMI. The viewing scope 26 further comprises a control handle 28 attached to a proximal end of the shaft 24 . The control handle 28 includes a steering lever 30 which can be advanced and retracted to selectively deflect or “steer” a distal region 32 of the shaft 24 , as shown in broken line. The control handle 28 will further include a connector for compiling a light source and an optical element of the viewing scope to a suitable screen and power source (not shown).
[0037] As shown in FIG. 3 , a distal tip 40 of the steerable shaft 24 of the viewing scope 26 is introduced through the entire length of the sheath 12 of the stone capture device 10 so that said distal end is received in and attached to a distal tip 42 of the deployable sweeping structure. The deployable sweeping structure 18 is typically a woven or braided mesh, typically formed from polymeric or wire filaments or fibers, so that axial compression of the sweeping structure 18 from its tubular configuration (illustrated in FIG. 3 ) to a foreshortened configuration (as shown in FIGS. 4A and 5A , will cause the sweeping structure to assume a concave configuration, more particularly a conical configuration. Usually, the sweeping structure will be fabricated so that it preferentially bends and everts about a weakened region 44 , as shown in FIGS. 4A and 5A . Thus, a distal most portion 46 of the sweeping structure 18 will preferentially evert into a proximal most portion 48 . Thus, as the steerable shaft 24 is progressively pulled proximally, as shown by the arrows in FIGS. 4A and 5A , the steering structure progressively shortens with the forward diameter or width becoming larger.
[0038] The sweeping structure in its tubular configuration, as shown in FIG. 3 , has only a single wall and is thus relatively flexible, typically having a bending stiffness in the ranges set forth above. As the sweeping structure 18 is everted, however, the wall becomes doubled, increasing the bending stiffness within the ranges set forth above. The relatively flexible tubular configuration is desirable since it will be over the steerable distal region 32 of the viewing scope. Thus, the viewing scope may be steered even while the sweeping structure 18 is over it. When the sweeping structure is deployed, however, it will have more stiffness and rigidity to facilitate engaging and manipulating the urinary stones within the kidney or bladder. As the deployed sweeping structure is distal to the distal end of the steerable shaft 24 , however, the structure will not interfere with steering and advancement.
[0039] The sweeping structure mesh is preferably constructed from a wire braid. Usually eight to 36 wires are used to construct braid. The wire will usually be formed from a flexible metal or polymer material such as a superelastic nickel-titanium alloy (nitinol), a nylon, or a polyethylene terephthalate (PET).
[0040] The sweeping structure 18 will further include a mechanism for drawing the open end closed after it has been partially or fully deployed. In the exemplary embodiments of FIGS. 3, 4A -B, and 5 A-B, the structure to close the end is a simple filament or suture 60 which passes through the mid-section of the sweeping structure which becomes the forward edge of the sweeping structure after deployment. Thus, by pulling on the filament, the filament acts as a purse string to draw the sweeping structure closed, as illustrated in FIG. 7D discussed below.
[0041] The viewing scope 26 will be introduced into the urinary tract UT with a stone capture device 10 disposed thereover, as illustrated in FIG. 6 . The assembly of the viewing scope 26 and the stone capture device 10 is introduced in the same manner as a conventional ureteroscope without the stone capture device. That is, a distal end of the assembly of the present invention will be introduced through the urethra URTH into the bladder B, and optionally further through the ureter URE and into the kidney K. Once in the kidney, the non-deployed sweeping structure 18 and the distal region 32 of the viewing scope may be steered together using the lever 30 of the viewing scope which selectively deflects a distal portion of the shaft 24 of the viewing scope 26 .
[0042] As illustrated in FIG. 7A , the kidney K may have a number of kidney stones KS therein. The sweeping structure 18 and distal region 32 may be steered while the physician views through the optical element 70 of the viewing scope (illustrated in FIGS. 4B and 5B ). While viewing, illumination will be provided by a light source 72 on the viewing scope. Once a target kidney stone KS is located, as shown in FIG. 7A , the sweeping structure 18 may be deployed, as shown in FIG. 7B . The combination stone capture device 10 and viewing scope 26 ( FIG. 2 ) may then be advanced, while continuing to optically view the region, until the deployed sweeping structure 18 engages a wall of the kidney, as shown in FIG. 7C , to capture the kidney stone between the sweeping structure and the wall. An optical (laser) fiber 80 or other stone fragmentation device may then be introduced through the working channel 74 ( FIGS. 4B and 5B ) of the viewing scope and advanced into the region where the stone is captured. By applying laser or other energy to the stone, the stone will be fragmented. Preferably, irrigation medium will be introduced simultaneously through the working channel to sweep the resulting stone fragments into the double-walled mesh of the deployed sweeping structure, thus simultaneously clearing the scope's field of view and entrapping the stone fragments therein. Occasionally, stones in the kidney are trapped within one of the cul-de-sac-like calices of the kidney. The sweeping structure may be advantageously deployed over the mouth of such a calyx to contain the stone and fragments produced by the lithotripsy process, in exactly the same manner as above. After the stone has been fragmented sufficiently, and the stone fragments captured, the filaments 60 may be retracted in order to close the sweeping structure 18 over the stone fragments, as shown in FIG. 7D . At that point, the combined assembly of the stone capture device 10 and the viewing scope 26 may be withdrawn from the urinary tract. After the procedure is complete, the stone capture device 10 may be removed from the viewing scope 26 , and the stone capture device will usually be disposed of in a conventional manner. The viewing scope, however, can be sterilized and reused in subsequent procedures.
[0043] Referring now to FIGS. 8A-8C , an alternative perforate sweeping structure 100 comprises a carrier sleeve 102 attached at the distal end of a hypotube or other elongate tubular member 104 . A pusher rod 106 extends coaxially through an inner passage or lumen of the hypotube 104 and is attached to a perforate sweeping structure 108 which is in a proximally retracted, radially collapsed configuration as shown in FIG. 8A . By pushing on the rod 106 , typically using handle 110 while holding on to a second handle 112 which is attached at the proximal end of the hypotube 104 , the self-expanding perforate sweeping structure 108 can be distally advanced so that it is released from the sleeve 102 and expands into an open conical configuration, as shown in FIG. 8B . A proximal end 112 of the perforate sweeping structure 108 will also expand to open and align with a passage or lumen 114 ( FIG. 8A ) which runs through the carrier sleeve 102 .
[0044] The sweeping structure assembly 100 may then advance over a viewing scope 120 ( FIG. 8B ) by advancing a proximal end of the scope into the passage 114 of the sleeve 102 . The hypotube 104 may be used to distally advance the sleeve 102 over the viewing structure 120 until the sleeve 102 approaches a distal end 122 of the viewing scope 120 , as best seen in FIG. 8B . At that point, the viewing scope 120 and/or the assembly of sleeve 102 and hypotube 104 may be manipulated to cause the deployed perforate sweeping structure 108 to capture kidney stones KS therein. By then engaging a distal periphery 124 of the perforate sweeping structure 108 against the wall W, of the body cavity, kidney stones KS may be captured and energy applied through an optical fiber advanced through a working channel of the viewing scope 120 in order to disrupt the stones. After the stones are disrupted into a plurality of small fragments, the hypotube 104 may be retracted proximally in order to draw and collapse the sweeping structure 108 back into the passage 114 of sleeve 102 (as shown in FIG. 8C ), optionally after the viewing scope 120 has been at least partially retracted therein. The viewing scope and sweeping structure assembly 100 may then be withdrawn from the body cavity to remove the stones.
[0045] FIG. 9 illustrates the use of the stone capture device 10 in the bladder B for retention and removal of a bladder stone BS or a growth G or malignancy. The device 10 is utilized in a similar manner as in the kidney K as illustrated in FIG. 7A-D . The everted porous cone 18 is not utilized as a sweeping structure, but is still utilized as a containment device to isolate and to trap tissue fragments removed during debulking. In the case of biopsy rather than removal or debulking, the containment structure 18 is similarly used to isolate the region to be sampled, then will serve to collect those samples for simultaneous removal.
[0046] FIG. 10 illustrates the use of the device 10 in a duct or vessel such as a ureter, colon, hepatic duct, airway, or blood vessel where there is not a large body cavity relative to the endoscope. In this case, the device 10 is shown in use in the ureter URE where there is situated a growth G or stone S shown completely obstructing the duct lumen. FIG. 10A illustrates the growth G distorting the ureter URE, so that the ureter is partly obstructed adjacent to the growth, not allowing good access by ureteroscope 12 to growth G. FIG. 10B illustrates the deployment of everted porous cone 18 , again as a containment structure but also as a dilation structure to improve visualization and access to growth G. Once the procedure is completed, multiple fragments may be removed simultaneously as in FIG. 7D .
[0047] While the above is a complete description of the preferred embodiments of the invention, various alternatives, modifications, and equivalents may be used. Therefore, the above description should not be taken as limiting the scope of the invention which is defined by the appended claims. | A stone or tissue capture device comprises a shaft with a deployable sweeping/containment structure at its distal end. The shaft is adapted to be removably placed over and connected to a conventional endoscope. The combination of the capture device and endoscope can be introduced into the various body lumens to capture, fragment/excise, and remove stones or tissue from the bladder and kidney, stomach, peritoneum, and from lumens such as the ureter, colon, hepatic ducts, airways, or blood vessels. | 0 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates generally to fabric handling systems and, more particularly, to a system for precisely moving a fabric panel from a stack of fabric panels to a work station.
2. Description of the Prior Art
Fabric panels for apparel are typically cut or die cut and bundled into packages for subsequent transfer to a work station where the bundles are opened and the panels are assembled into garments or partial garments. In the past this has primarily been a manual operation since fabric pieces are soft goods and are easily distorted by mechanical handling systems. However, with the advent of more sophisticated material handling systems there has been renewed interest in automating at least some sewing operations.
One operation which has resisted automation is the removal of a fabric panel from a stack of fabric pieces and presentation of the fabric panel to a work station for a sewing operation. Some attempts have been made at this operation by the use of fabric pickups in combination with edge detectors to locate at least the leading edge of the fabric piece. However, because lightweight knitted fabric pieces are easily distorted by mechanical handling, such systems have only been successful with heavy weight fabrics such as denim.
Thus, there remains a need for a new and improved fabric panel loader which is operable both to remove a fabric panel from a stack of fabric pieces and to precisely position the fabric panel for transfer to a work station.
SUMMARY OF THE INVENTION
The present invention is directed to a fabric panel loader for automatically feeding a fabric panel from a stack of fabric pieces to a work station. The apparatus includes a fabric pickup assembly for removing the fabric panel from the stack of fabric pieces and transferring the panel to a smoothing table. The smoothing table receives the fabric panel and automatically moves the fabric panel from the stack of fabric pieces to a predetermined orientation. The smoothing table includes a table for receiving the fabric panel from the stack of fabric pieces and drive means attached to the table for moving the table. A vision system connected to the drive means controls the drive means to move the table in response a control signal indicating the position of the fabric panel. A panel loader removes the fabric panel from the table and transfers the panel to the work station.
Accordingly, one aspect of the present invention is to provide an apparatus for automatically feeding a fabric panel from a stack of fabric pieces to a work station. The apparatus includes: (a) a table for receiving the fabric panel from the stack of fabric pieces, the table being operable to move the fabric panel into a predetermined orientation; and (b) a panel loader for removing the fabric panel from the table and transferring the panel to the work station.
Another aspect of the present invention is to provide an apparatus for automatically moving a fabric panel from a stack of fabric pieces to a predetermined orientation. The apparatus includes: (a) a table for receiving the fabric panel from the stack of fabric pieces; (b) drive means attached to the table for moving the table; and (c) a vision system connected to the drive means for controlling the drive means to move the table in response a control signal indicating the position of the fabric panel.
Still another aspect of the present invention is to provide an apparatus for automatically feeding a fabric panel from a stack of fabric pieces to a work station. The apparatus includes: (a) a fabric pickup assembly for removing the fabric panel from the stack of fabric pieces and transferring the panel; (b) a smoothing table for receiving the fabric panel and for automatically moving the fabric panel from the stack of fabric pieces to a predetermined orientation, the smoothing table including: (i) a table for receiving the fabric panel from the stack of fabric pieces; (ii) drive means attached to the table for moving the table; and (iii) a vision system connected to the drive means for controlling the drive means to move the table in response a control signal indicating the position of the fabric panel; and (c) a panel loader for removing the fabric panel from the table and transferring the panel to the work station.
These and other aspects of the present invention will become apparent to those skilled in the art after a reading of the following description of the preferred embodiment when considered with the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side elevational view of a panel feeding machine constructed according to the present invention;
FIG. 2 is an enlarged side elevational view of the smoothing table shown in FIG. 1;
FIG. 3 is an enlarged front elevational view of the smoothing table shown in FIG. 1;
FIG. 4 is an enlarged top view of the smoothing table shown in FIG. 1;
FIG. 5 is an enlarged side elevational view of the panel loader shown in FIG. 1;
FIG. 6 is an enlarged front elevational view of the panel loader shown in FIG. 1;
FIG. 7 is an enlarged top view of the panel loader shown in FIG. 1; and
FIG. 8 is an enlarged side elevational view of a single unloader pick-up device.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
In the following description, like reference characters designate like or corresponding parts throughout the several views. Also in the following description, it is to be understood that such terms as "forward", "rearward", "left", "right", "upwardly", "downwardly", and the like are words of convenience and are not to be construed as limiting terms.
Referring now to the drawings in general and FIG. 1 in particular, it will be understood that the illustrations are for the purpose of describing a preferred embodiment of the invention and are not intended to limit the invention thereto. As best seen in FIG. 1, there is shown a panel feeding machine, generally designated 10, constructed according to the present invention.
Panel feeding machine 10 includes a supply magazine 14 for holding a stack of fabric pieces 16. An unloader assembly 20 adjacent to supply magazine 14 removes single panels of fabric pieces from stack 16 and transfers them one panel at a time to smoothing table 22. A vision system 24 located above smoothing table 22 is connected to a controller 26 to orient smoothing table 22 whereby panel loader assembly 30 can pick up the oriented fabric panel and move it for a subsequent operation.
Unloader assembly 20 includes a linear slide frame 32 for moving a plurality of pick-up heads 34 into an operable position with the top of the stack 16 of fabric pieces and to grasp an individual panel of fabric and remove it from stack 16. Drive means 36 connected to slide frame 32 moves the plurality of pick-up heads 34 in the x and z directions up and away from the upper surface of the stack 16 of fabric pieces and over and down onto the upper surface of smoothing table 22.
Smoothing table 22 includes a platen 40 having a flat upper surface and forming a plenum. A drive assembly 42 is attached to the lower portion of platen 40 for moving the platen in the x, y and theta directions. A source of vacuum 44 is connected to the plenum chamber of platen 40 for causing the fabric panel to remain stationary on the upper surface of platen 40.
Panel loader assembly 30 includes a linear slide frame 46 for supporting a plurality of vacuum pick-up arms 50. Drive means 52 moves slide frame 46 in the x direction between a position above the surface of smoothing table 22 to a second position where the fabric panel is presented to a work station for subsequent operations.
As best seen in FIG. 2, there is shown an enlarged side elevation view of the smoothing table 22. Smoothing table 22 includes a base 54 onto which an x-slide 56 and an x-drive means 60 are attached thereto. The upper surface of platen 40 includes an edge smoothing assembly 62. The edge smoothing assembly 62 generally includes a drive means 64 for moving a plurality of plates 66 on the surface of platen 40 by means of a lead-screw assembly 70. The movement of the plates outwardly from the center of the platen and parallel to the surface of the platen operates to remove wrinkles from the fabric panel.
Turning now to FIG. 3, there is shown an enlarged front elevation view of the smoothing table 22. As can be seen, smoothing table 22 also includes a y-linear slide 72 and a y-drive means 74 from moving the table in the y direction. In combination with x slide 56 and x drive means 60 and theta drive means 76, the table can be oriented in three degrees of freedom by the operation of vision system 24 and controller 26.
As best seen in FIG. 4, there is shown an enlarged top view of the smoothing table 22. The upper surface of platen 40 includes a plurality of perforated apertures 80 whereby a source of vacuum 44 provides a stream of air through the perforated apertures adjacent to the upper surface and the fabric panel on the surface thereby causing the fabric panel to remain stationary on the surface of the platen. In their initial position, smoothing plates 66 extend over the surface of the platen until the fabric plan is transferred to the surface of the platen. At that point, drive 64 is actuated and smoothing plates 66 are moved outwardly by lead screw assembly 70 simultaneously thereby causing the surface of the fabric panel to be smoothed. After the fabric panel is smoothed onto the upper surface platen 40 and platen 40 is oriented by vision system 24 and controller 26 and drives 60, 74, and 76, panel loader assembly 30 moves into position to pick up the oriented fabric panel.
As best seen in FIG. 5, there is shown an enlarged side elevational view of the panel loader shown in FIG. 1. In addition to the x-drive means 52, panel loader assembly 30 also includes a y-drive means 82 for moving the panel loader assembly with respect to the upper surface of platen 40 and the fabric panel thereon. Each of the plurality of vacuum pick-up arms 50 include perforated apertures 84 connected to a second source of vacuum 93 for removing the fabric panel from the upper surface of platen 40. While other types of pick-up devices can be used, a vacuum pick-up device ensures the most positive positioning of the fabric panel since the surface of the fabric panel is not distorted mechanically.
Turning now to FIG. 6, there is shown an enlarged front elevational view of panel loader assembly 30. As can be seen, panel loader assembly 30 preferably includes two types of vacuum pick-up arms 50. A central stationary arms 84 pick up the central portion of the fabric panel. A pair of pivotable arms 86 move from a outward position 86a to an inward position rotated 90° with respect to the surface of the platen 86b by means of cam followers 88. This arrangement allows the outer edges of the fabric panel to be oriented at 90° to the central portion of the fabric panel thereby permitting the fabric panel to be utilized in subsequent sewing operations.
As best seen in FIG. 7, there is shown an enlarged top view of the panel loader assembly 30. As can be seen, drive 90 is connected to lead screws 92 for moving outward pivotable arms 86 along cam followers 88 to orient the arms between parallel and 90° orientation.
Finally, turning to FIG. 8, there is shown an enlarged side elevation view of a single unloader pick-up device 34 used in unloader 20. In the preferred embodiment, fabric pick-up device 34 includes a mounting base 96 which is attached to support 94. A frame 100 is slidably mounted to the base 96 thereby allowing the pick-up device to adjust for variations in the height of the stack 16 of fabric pieces. A gripper head 102 is attached to one end of the frame 100.
Gripper head 102 includes a stationary jaw 104 and a moveable jaw 106. The jaws 104, 106 are actuated by a pneumatic cylinder 110 having one end attached to bracket 112 and the other end attached to a Jaw actuator. In the preferred embodiment, an air ejector tube 114 passes through frame 100 and has one end connected to a source of compressed air and the other end adjacent to jaws 104, 106.
In operation, the pick-up device is positioned adjacent to the top ply fabric piece and brought in contact with the surface of the fabric piece. The pickup device is then actuated to grasp the surface of the fabric piece and to lift it upwardly to separate it from the adjacent fabric piece. The pick-up device is then moved in a linear fashion to place the fabric piece onto the smoothing table where it can be smoothed and oriented for pick-up by panel loader assembly 30.
Certain modifications and improvements will occur to those skilled in the art upon a reading of the foregoing description. By way of example, the fabric magazine could be replaced with a die cut machine directly adjacent to the table for supplying the fabric pieces. Also, electrostatic means could be used to hold the fabric pieces in place instead of vacuum. It should be understood that all such modifications and improvements have been deleted herein for the sake of conciseness and readability but are properly within the scope of the following claims. | A fabric panel loader for automatically feeding a fabric panel from a stack of fabric pieces to a work station. The apparatus includes a fabric pickup assembly for removing the fabric panel from the stack of fabric pieces and transferring the panel to a smoothing table. The smoothing table receives the fabric panel and automatically moves the fabric panel from the stack of fabric pieces to a predetermined orientation. A panel loader removes the fabric panel from the table and transfers the panel to the work station. | 3 |
Applicant hereby claims priority under 35 U.S.C. §119 from Provisional Application No: 60/337,260 filed on Nov. 2, 2001, the disclosure of which is herein incorporated by reference.
BACKGROUND OF THE INVENTION
This invention relates generally to loading individual cartridges or shells into a magazine clip of the type used with automatic weapons, particularly automatic and semiautomatic pistols.
The known method for loading cartridges into a magazine clip is by manually inserting each shell into the open end of the clip by depressing the slug end of the cartridge with the heel or rim end of the next shell so that entry of each of the shells follows in generally reverse motion to that which the shell will ultimately take as it leaves the magazine clip and enters the firing chamber of the pistol.
Such a procedure requires two hands for so loading the magazine clip, a decided disadvantage to those who are capable of firing a pistol once it is loaded, but who are disabled and can only use one hand for this operation.
SUMMARY OF THE INVENTION
In accordance with the present invention for loading cartridges into a conventional magazine clip, a tray is provided with cavities or receptacles for holding each of the individual cartridges to be loaded in side by side relationship. Each cavity includes means for centering the cartridges in each of the cavities, and nevertheless provides sufficient clearance on either side of the cartridge to allow the clip to be forcibly pushed downwardly against the cartridge in the cavity at a slight angle to the orientation of the cavity, that is not normally to the tray but rather at approximately a 70-degree angle thereto. The magazine clip is then used to apply pressure from the heel of the follower provided in the magazine clip or a cartridge that has already been loaded to push the cartridge to be loaded from the tray against the rear of its associated cavity, and to thereby move the follower or the cartridges already in the clip further into the clip to allow space for the cartridge to be loaded to enter the clip itself.
The tray defining the side-by-side cavities for each of the cartridges to be loaded preferably is of elongated rectangular configuration perpendicular to the axes of the various cavities, and preferably includes a non-slip surface on the back surface plus counter sunk openings receive fasteners for securing the tray to the countertop or the like. This later configuration is especially convenient in the environment of a firing range or the like.
It is nevertheless a feature of the present invention that a tray constructed in accordance with the above-described parameters can be conveniently carried about by a disabled marksman who will be able then to load cartridges into his semi-automatic weapon magazine clip using only one hand.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows the prior art manual approach to loading cartridges into a semiautomatic weapon magazine clip.
FIG. 2 is a perspective view showing a tray constructed in accordance with the present invention.
FIG. 2A is a sectional view taken generally on the line 2 A of FIG. 2 and showing a cartridge in cavity.
FIG. 3A is an elevational view showing in vertical section, the initial position assumed by the user to prepare for loading a cartridge into the magazine clip.
FIG. 3B is a view subsequent to that of FIG. 3A wherein the cartridge is being driven into the magazine clip as a result of the user continuing to exert downward and in the direction of the arrow to drive the cartridge in the clip. Note that the clip is driven toward the user slightly as indicated generally by the arrow “A” in FIG. 3 B.
FIG. 3C shows the cartridge loaded into the clip.
DETAILED DESCRIPTION
FIG. 1 shows a conventional approach to loading individual cartridges C into a magazine clip M of the type used in present day automatic pistols. The user must grip the magazine clip in one hand, and the cartridge to be loaded in the other, while he applies pressure onto the nose or slug end of a cartridge previously loaded into magazine M by applying a force to that loaded cartridge in an appropriate direction to achieve movement of that cartridge against the bias of an internal spring provided in the magazine until he can slide the cartridge C to be loaded into place. This operation is repeated sequentially until the desired number of cartridges have been loaded into the magazine M. The magazine clip M typically includes a biased follower F that must itself be depressed in the same manner to achieve loading of the first or initial cartridge in accordance with this prior art technique.
FIGS. 3A and 3B show the magazine clip M and the spring biased follower F. The clip M is gripped by the user who uses the magazine itself as a sort of a handle in carrying out the method of the present invention using the cartridge tray of the present invention.
FIG. 2 shows a tray T which is preferably fabricated of a high-density polymeric or plastic/synthetic material of the type that exhibits a degree of lubricity. The tray T is formed with a plurality of cartridge-cavities, 10 , 10 preferably corresponding in number to the number of cartridges to be loaded in the magazine clip M. Each cavity 10 has a forward end 10 a and a rearward end 10 b, which are spaced apart from one another, a distance that exceeds the length of the cartridge C to be loaded.
Each of the cavities 10 is somewhat greater in width W than the diameter of the cartridge C as best shown in FIG. 2 A. As also shown in FIG. 2A, each of the cavities 10 includes a central groove 10 c which extends at least approximately the length of the cavity 10 for supporting the cartridges C,C in centered relationship in each of the cavities 10 again as suggested for example in FIG. 2 A. The width W is designed to accommodate the width defined by flanges M 1 , on the clip as suggested in FIG. 3 B.
Once the user has placed his cartridges in the cavities 10 of the tray T, he can grasp the magazine clip M and hold it in the position shown in FIG. 3 A. By applying a downward pulling force as indicated by the arrow 12 in FIG. 3A, the user can with one hand push the rear end of cartridge C 1 against the slug end of the cartridge C in the tray T, and thereby displace the cartridge C 1 upwardly against the force of the spring S in the magazine clip M. Further pressure in the rearward direction coupled by a slight forward rocking motion as indicated by the arrow 12 in FIG. 3A will result in the cartridge C ultimately assuming the position for the cartridge C 1 as suggested in FIG. 3 C.
This process can be repeated until all of the cartridges are loaded into the magazine clip, and in accordance with the present invention, only one hand is required to complete this operation.
In light of the above, it is therefor understood that within the scope of the appended claims, the invention may be practiced otherwise then as specifically described. | A method and apparatus for loading cartridges into a gun magazine clip from a tray. The cartridges are arranged in tray cavities that hold each cartridge so the clip can be manipulated with one hand to load each cartridge in succession. | 5 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] The present continuation Application claims the benefit of priority under 35 U.S.C. §120 to application Ser. No. 10/006,298, filed Dec. 6, 2001, and under 35 U.S.C. § 119 from United Kingdom Application No. 0029863.8, filed on Dec. 7, 2000, the entire contents of both are hereby incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to embedding data in material. Embodiments of the present invention relate to watermarking.
[0004] Material as used herein means information material represented by information signals and material includes at least one or more of image material, audio material and data material. Image material is generic to still and moving images and includes video and other forms of information signals represents images.
[0005] 2. Description of the Prior Art
[0006] Steganography is the embedding of data into material such as video material, audio material and data material in such a way that the data is imperceptible in the material.
[0007] Data may be embedded as a watermark in material such as video material, audio material and data material. A watermark may be imperceptible or perceptible in the material.
[0008] A watermark may be used for various purposes. It is known to use watermarks for the purpose of protecting the material against, or trace, infringement of the intellectual property rights of the owner(s) of the material. For example a watermark may identify the owner of the material.
[0009] Watermarks may be “robust” in that they are difficult to remove from the material. Robust watermarks are useful to trace the provenance of material which is processed in some way either in an attempt to remove the mark or to effect legitimate processing such as video editing or compression for storage and/or transmission. Watermarks may be “fragile” in that they are easily damaged by processing which is useful to detect attempts to remove the mark or process the material.
[0010] Visible watermarks are useful to allow e.g. a customer to view an image e.g. over the Internet to determine whether they wish to buy it but without allowing the customer access to the unmarked image they would buy. The watermark degrades the image and the mark is preferably not removable by the customer. Visible watermarks are also used to determine the provenance of the material into which they are embedded.
[0011] FIG. 1 shows one such known apparatus, generally 100 , for embedding a transform domain watermark in an image. The image 105 is received by the transformer 110 and output as a transform domain image 115 . The transform domain watermark 145 is then applied to the transform domain image 115 by the combiner 120 which outputs a transform domain watermarked image 125 . The transform domain watermarked image 125 is then received by the inverse transformer 130 and output as a spatial domain watermarked image 135 .
[0012] However, a problem arises in that the image 105 may be degraded by the operation of both the transformer 110 and inverse transformer 130 . The transformers 110 , 130 need to be very accurate to ensure that any degradation is minimised. Accurate transformers are relatively expensive and two are required.
SUMMARY OF THE INVENTION
[0013] According to one aspect of the present invention there is provided an apparatus comprising a transformer for transforming transform domain data into spatial domain data; and a combiner for receiving material and combining said spatial domain data with said material to form data embedded material.
[0014] Hence, in preferred embodiments the material is not subject any transformation at all. One less transformer is required than the prior art approach thereby reducing cost and complexity. Advantageously, since only the transform domain watermark is transformed the transformer can have less precision and range thereby further reducing cost and complexity.
[0015] According to another aspect of the present invention there is provided a method comprising the steps of a) transforming transform domain data into spatial domain data; and b) combining said spatial domain data with material to form data embedded material.
[0016] According to a further aspect of the present invention there is provided a computer program product arranged to carry out the method of said another aspect when run on a computer.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] The above and other objects, features and advantages of the invention will be apparent from the following detailed description of illustrative embodiments which is to be read in connection with the accompanying drawings, in which:
[0018] FIG. 1 is a block diagram illustrating a prior art watermarking apparatus;
[0019] FIG. 2 is a block diagram illustrating a watermark apparatus according to an embodiment of the present invention;
[0020] FIG. 3 is a block diagram illustrating a watermark apparatus according to another embodiment of the present invention;
[0021] FIG. 4 is a block diagram illustrating an embodiment of the strength adapter of FIG. 3 ;
[0022] FIG. 5 is a block diagram illustrating a watermark apparatus according to a further embodiment of the present invention;
[0023] FIGS. 6A and 6B illustrate a UMW structure; and
[0024] FIGS. 7A and 7B illustrate wavelet processing and notation.
DESCRIPTION OF PREFERRED EMBODIMENTS
[0025] Whilst the embodiments described herein refer to images and watermarking images it will be appreciated that the technique can be equally be applied to other material such as audio, video and data generally.
[0026] FIG. 2 illustrates a watermark apparatus, generally 200 , according to an embodiment of the present invention. The watermark apparatus 200 comprises an inverse transformer 210 and a combiner 220 . In overview, the watermark apparatus 200 receives a spatial domain image 105 and a transform domain watermark 145 , and outputs a spatial domain watermarked image 225 . The transform domain watermark 145 is inverse transformed in a transformer 210 and combined with the spatial domain image 105 in a combiner 220 to produce the spatial domain watermarked image 225 . Only the transform domain watermark 145 , and not the spatial domain image 105 , is subject to subject any transformation. The spatial domain image 105 is not subject to any lossy processing which may degrade the spatial domain image 105 and is fully recoverable.
Spatial Domain Image 105
[0027] The spatial domain image 105 is preferably a digital bitmap. The digital bitmap comprises of a plurality of pixels, each pixel having a particular binary value.
Transform Domain Watermark 145
[0028] The transform domain watermark 145 comprises encoded watermark information. The transform domain watermark 145 is preferably a digital bitmap. The digital bitmap comprises of a plurality of pixels, each pixel having a particular binary value, each particular binary value encoding the watermark information.
[0029] The transform domain watermark 145 may comprise wavelet coefficients, each coefficient being represented by one pixel of the digital bitmap. Wavelets are described in more detail below the section entitled wavelets. The value of each wavelet coefficient encodes the watermark information. The wavelet has watermark information which is encoded in coefficients in at least two bands in at least one level. In preferred embodiments, the upper horizontal band, hH 1 , hV 1 and the upper vertical band, 1H 1 , hV 1 are used to encode the watermark information as watermark information encoded in these bands have been found not to be readily perceptible in the spatial representation. Furthermore, watermark information is encoded in these bands because it has been found to be robust to image compression techniques such as those agreed by the Joint Picture Expert Group (JPEG). However, it will be appreciated that the watermark information may be encoded in any suitable coefficients and any band or level as appropriate.
[0030] Alternatively, the transform domain watermark 145 may comprise Discrete Cosine Transform (DCT) coefficients, each coefficient being represented by one pixel of the digital bitmap. DCTs are well known in the art. Preferably, the value of each DCT coefficient encodes the watermark information.
[0031] The watermark information may, for example, identify the owner of the spatial domain image 105 or provide other information associated with the spatial domain image 105 . Preferably, the watermark information comprises a Universal Material Identifier (UMID) associated with the spatial domain image 105 . The use of a UMID is advantageous as it provides for unique identification of the spatial domain image 105 . UMIDs are described in more detail below in the section entitled UMIDs. Preferably, the watermark information is encoded by a Pseudo Random Symbol Stream. The use of Pseudo Random Symbol Stream encoding is advantageous as it reduces the visual perceptibility of the watermark and makes it more difficult for the watermark information to be isolated or removed. The Pseudo Random Symbol Stream spreads the watermark over many coefficients. Encoding or ‘spreading’ using Pseudo Random Symbol Stream's is well known in the art. The watermark information may also be subject to en- or correction coding to improve decoding success rates.
Inverse Transformer 210
[0032] The inverse transformer 210 receives the transform domain watermark 145 and transforms transform domain watermark 145 into a spatial domain watermark 215 . Where the transform domain watermark 145 comprises wavelet coefficients, the inverse transformer 210 comprises an inverse wavelet transformer. Where the transform domain watermark 145 comprises DCT coefficients, the inverse transformer 210 comprises an inverse DCT transformer. It will be appreciated that other techniques for transform domain representation may also be used and suitable inverse transformers will be required as appropriate. Since only the transform domain watermark 145 , and not the spatial domain image 105 , is to be transformed the inverse transformer 210 can have less precision and range thereby further reducing cost and complexity. Any losses introduced into the spatial domain watermark 215 by the inverse transformer 210 may be recovered using decoding techniques such as error correction coding.
[0033] The spatial domain watermark 215 is preferably a digital bitmap. The digital bitmap comprises of a plurality of pixels, each pixel having a particular value.
Combiner 220
[0034] The combiner 220 receives the spatial domain image 105 and the spatial domain watermark 215 , and outputs a spatial domain watermarked image 225 . The combiner 220 arithmetically combines respective pixels of the spatial domain image 105 and the spatial domain watermark 215 to produce the spatial domain watermarked image 225 .
ALTERNATIVE EMBODIMENT
[0035] FIG. 3 illustrates a watermark apparatus, generally 300 , according to another embodiment of the present invention. The watermark apparatus 300 is similar to the arrangement of FIG. 2 but with the inclusion of a strength adapter 310 . The strength adapter 310 adapts the strength of the spatial domain watermark 215 in dependence on the spatial domain image 105 to produce a strength adapted spatial domain watermark 315 . The combiner 220 arithmetically combines respective values of the spatial domain image 105 and the strength adapted spatial domain watermark 315 to produce a spatial domain watermarked image 325 .
[0036] The strength adapter 310 allows the strength of the watermark spatial domain watermark 215 to be adapted such that the strength adapted spatial domain watermark 315 is not readily perceptible in the spatial domain watermarked image 325 . Each pixel of the spatial domain watermark 215 may be individually adapted in dependence on respective pixels of the spatial domain image 105 . Alternatively, a predetermined number of pixels of the spatial domain watermark 215 may be adapted in dependence on particular representative pixels of the spatial domain image 105 .
[0037] FIG. 4 illustrates an embodiment of the strength adapter of FIG. 3 . The strength adapter 310 comprises a generator 410 and a multiplier 420 . The generator 410 receives the spatial domain image 105 and generates strength control information 415 . The strength control information 415 is received by the multiplier 420 which, in response, adapts the magnitude of the spatial domain watermark 215 to produce a strength adapted spatial domain watermark 315 .
[0038] The generator 410 may generate strength control information 415 such that each pixel of the spatial domain watermark 215 may be individually adapted in dependence on respective pixels of the spatial domain image 105 . Alternatively, the generator 410 may generate strength control information 415 such that a predetermined number of pixels of the spatial domain watermark 215 may be adapted in dependence on particular representative pixels of the image 105 . The strength control information 415 (α) is generated using the algorithm α=F(Image), where F(Image) is a function representing the ability of the image 105 to mask respective pixels of the spatial domain watermark 215 .
[0039] The strength adapted spatial domain watermark 315 is then combined by the combiner 220 with the image 105 to produce a spatial domain watermarked image 325 as described above.
FURTHER EMBODIMENT
[0040] FIG. 5 illustrates a watermark apparatus, generally 400 , according to a further embodiment of the present invention. The watermark apparatus 400 is similar to the arrangement of FIG. 4 but with the strength adaptation being performed in the transform domain instead of the spatial domain. Hence, a transformer 430 is provided which transforms the spatial domain image 105 into a transform domain image 535 .
[0041] The generator 410 receives the transform domain image 535 and generates strength control information 515 . The strength control information 515 is received by the multiplier 420 which, in response, adapts the magnitude of the transform domain watermark 145 to produce a strength adapted transform domain watermark 545 .
[0042] The generator 410 may generate strength control information 515 such that each pixel of the transform domain watermark 145 may be individually adapted in dependence on respective pixels of the transform domain image 535 . Alternatively, the generator 410 may generate strength control information 515 such that a predetermined number of pixels of the transform domain watermark 145 may be adapted in dependence on particular representative pixels of the transform domain image 535 .
[0043] The inverse transformer 210 receives the strength adapted transform domain watermark 545 and transforms the strength adapted transform domain watermark 545 into a strength adapted spatial domain watermark 555 .
[0044] The strength adapted spatial domain watermark 555 is then combined by the combiner 220 with the spatial domain image 105 to produce a spatial domain watermarked image 525 as described above.
[0045] Hence, it will be appreciated that only the transform domain watermark 145 , and not the image 105 , is subject to any transformation. Accordingly, the image 105 is not subject to any lossy processing and will be fully recoverable.
UMIDs
[0046] FIGS. 6A and 6B illustrate a UMID structure.
[0047] The UMID is described in SMPTE Journal March 2000. Referring to FIG. 6A an extended UMID is shown. It comprises a first set of 32 bytes of basic UMID and a second set of 32 bytes of signature metadata.
[0048] The first set of 32 bytes is the basic UMID. The components are:
A 12-byte Universal Label to identify this as a SMPTE UMID. It defines the type of material which the UMID identifies and also defines the methods by which the globally unique Material and locally unique Instance numbers are created. A 1-byte length value to define the length of the remaining part of the UMID. A 3-byte Instance number which is used to distinguish between different instances' of material with the same Material number. A 16-byte Material number which is used to identify each clip. Each Material number is the same for related instances of the same material.
[0053] The second set of 32 bytes of the signature metadata as a set of packed metadata items used to create an extended UMID. The extended UMID comprises the basic UMID followed immediately by signature metadata which comprises:
An 8-byte time/date code identifying the time and date of the Content Unit creation. A 12-byte value which defines the spatial co-ordinates at the time of Content Unit creation. 3 groups of 4-byte codes which register the country, organisation and user codes
[0057] Each component of the basic and extended UMIDs will now be defined in turn.
[0058] The 12-byte Universal Label
[0059] The first 12 bytes of the UMID provide identification of the UMID by the registered string value defined in Table 1.
[0000]
TABLE 1
Specification of the UMID Universal Label
Byte No.
Description
Value (hex)
1
Object Identifier
06h
2
Label size
0Ch
3
Designation: ISO
2Bh
4
Designation: SMPTE
34h
5
Registry: Dictionaries
01h
6
Registry: Metadata Dictionaries
01h
7
Standard: Dictionary Number
01h
8
Version number
01h
9
Class: Identification and location
01h
10
Sub-class: Globally Unique Identifiers
01h
11
Type: UMID (Picture, Audio, Data,
01, 02, 03, 04h
Group)
12
Type: Number creation method
XXh
[0060] The hex values in Table 1 may be changed: the values given are examples. Also the bytes 1 - 12 may have designations other than those shown by way of example in the table. Referring to the Table 1, in the example shown byte 4 indicates that bytes 5 - 12 relate to a data format agreed by SMPTE. Byte 5 indicates that bytes 6 to 10 relate to “dictionary” data. Byte 6 indicates that such data is “metadata” defined by bytes 7 to 10 . Byte 7 indicates the part of the dictionary containing metadata defined by bytes 9 and 10 . Byte 10 indicates the version of the dictionary. Byte 9 indicates the class of data and Byte 10 indicates a particular item in the class.
[0061] In the present embodiment bytes 1 to 10 have fixed preassigned values. Byte 11 is variable. Thus referring to FIG. 6B , and to Table 1 above, it will be noted that the bytes 1 to 10 of the label of the UMID are fixed. Therefore they may be replaced by a 1 byte ‘Type’ code T representing the bytes 1 to 10 . The type code T is followed by a length code L. That is followed by 2 bytes, one of which is byte 11 of Table 1 and the other of which is byte 12 of Table 1, an instance number (3 bytes) and a material number (16 bytes). Optionally the material number may be followed by the signature metadata of the extended UMID and/or other metadata.
[0062] The UMID type (byte 11 ) has 4 separate values to identify each of 4 different data types as follows:
[0063] ‘01h’=UMID for Picture material
[0064] ‘02h’=UMID for Audio material
[0065] ‘03h’=UMID for Data material
[0066] ‘04h’=UMID for Group material (i.e. a combination of related essence).
[0067] The last (12th) byte of the 12 byte label identifies the methods by which the material and instance numbers are created. This byte is divided into top and bottom nibbles where the top nibble defines the method of Material number creation and the bottom nibble defines the method of Instance number creation.
[0068] Length
[0069] The Length is a 1-byte number with the value ‘13h’ for basic UMIDs and ‘33W for extended UMIDs.
[0070] Instance Number
[0071] The Instance number is a unique 3-byte number which is created by one of several means defined by the standard. It provides the link between a particular ‘instance’ of a clip and externally associated metadata. Without this instance number, all material could be linked to any instance of the material and its associated metadata.
[0072] The creation of a new clip requires the creation of a new Material number together with a zero Instance number. Therefore, a non-zero Instance number indicates that the associated clip is not the source material. An Instance, number is primarily used to identify associated metadata related to any particular instance of a clip.
[0073] Material Number
[0074] The 16-byte Material number is a non-zero number created by one of several means identified in the standard. The number is dependent on a 6-byte registered port ID number, time and a random number generator.
[0075] Signature Metadata
[0076] Any component from the signature metadata may be null-filled where no meaningful value can be entered. Any null-filled component is wholly null-filled to clearly indicate a downstream decoder that the component is not valid.
[0077] The Time-Date Format
[0078] The date-time format is 8 bytes where the first 4 bytes are a UTC (Universal Time Code) based time component. The time is defined either by an AES3 32-bit audio sample clock or SMPTE 12M depending on the essence type.
[0079] The second 4 bytes define the date based on the Modified Julian Data (MJD) as defined in SMPTE 309M. This counts up to 999,999 days after midnight on the 17 Nov. 1858 and allows dates to the year 4597.
[0080] The Spatial Co-Ordinate Format
[0081] The spatial co-ordinate value consists of three components defined as follows:
Altitude: 8 decimal numbers specifying up to 99,999,999 metres. Longitude: 8 decimal numbers specifying East/West 180.00000 degrees (5 decimal places active). Latitude: 8 decimal numbers specifying North/South 90.00000 degrees (5 decimal places active).
[0085] The Altitude value is expressed as a value in metres from the centre of the earth thus allowing altitudes below the sea level.
[0086] It should be noted that although spatial co-ordinates are static for most clips, this is not true for all cases. Material captured from a moving source such as a camera mounted on a vehicle may show changing spatial co-ordinate values.
[0087] Country Code
[0088] The Country code is an abbreviated 4-byte alpha-numeric string according to the set defined in ISO 3166. Countries which are not registered can obtain a registered alpha-numeric string from the SMPTE Registration Authority.
[0089] Organisation Code
[0090] The Organisation code is an abbreviated 4-byte alpha-numeric string registered with SMPTE. Organisation codes have meaning only in relation to their registered Country code so that Organisation codes can have the same value in different countries.
[0091] User Code
[0092] The User code is a 4-byte alpha-numeric string assigned locally by each organisation and is not globally registered. User codes are defined in relation to their registered Organisation and Country codes so that User codes may have the same value in different organisations and countries.
[0093] Wavelets
[0094] FIGS. 7A and 7B illustrate wavelet processing and notation. Wavelets are well known and are described in for example “A Really Friendly Guide to Wavelets” by C Valens, 1999 (c.valensOlmindless.com) and available at http://perso.wanadoo.fr/polyvalens/clemens/wavelets/wavelets.html.
[0095] Valens shows that the discrete wavelet transform can be implemented as an iterated filter bank as used in sub-band coding, with scaling of the image by a factor of 2 at each iteration.
[0096] Thus referring to FIG. 7B , a spatial domain image is applied to a set of high pass HP and low pass LP filters. At level 1 , the first stage of filtering, the image is filtered horizontally and vertically and, in each direction, scaled down by a factor of 2. In level 2 , the low pass image from level 1 is filtered and scaled in the same way as in level 1 . The filtering and scaling may be repeated in subsequent levels 3 onwards.
[0097] The result is shown schematically in FIG. 7A . FIG. 7A is a representation normal in the art. The horizontal axis indicates increasing horizontal frequencies and the vertical axis indicates increasing vertical frequencies. At level one the image is spatially filtered into four bands: the lower horizontal and vertical band, 1H 1 , 1V 1 ; the upper horizontal band hH 1 , 1V 1 ; the upper vertical band 1H 1 , hV 1 ; and the upper horizontal and vertical band, hH 1 , hV 1 . At level 2 , the lower horizontal and vertical band, 1H 1 , 1V 1 is filtered and scaled into the lower horizontal and vertical band, 1H 2 , 1V 2 ; the upper horizontal band hH 2 , 1V 2 ; the upper vertical band 1H 2 , hV 2 ; and the upper horizontal and vertical band, hH 2 , hV 2 . At level 3 (not shown in FIG. 7A ), the lower horizontal and vertical band, 1H 2 , 1V 2 is further filtered and scaled.
[0098] In so far as the embodiments of the invention described above are implemented, at least in part, using software-controlled data processing apparatus, it will be appreciated that a computer program providing such software control and a storage medium by which such a computer program is stored are envisaged as aspects of the present invention.
[0099] Although particular embodiments have been described herein, it will be appreciated that the invention is not limited thereto and that many modifications and additions thereto may be made within the scope of the invention. For example, various combinations of the features of the following dependent claims could be made with the features of the independent claims without departing from the scope of the present invention. | An apparatus including a transformer for transforming transform domain data into time domain data and a combiner for receiving material and combining said time domain data with said material to form data embedded material. Hence, the material is not subject any transformation at all. | 7 |
PRIORITY CLAIM
This application is a continuation of U.S. patent application Ser. No. 09/907,954 filed Jul. 18, 2001 entitled “AIR-POWERED LOW INTERFACE PRESSURE SUPPORT SURFACE” and now U.S. Pat. No. 6,782,574 issued on Aug. 31, 2004. which, in turn, claimed benefit of U.S. Provisional Application No. 60/219,074, filed Jul. 18, 2000, both of which are incorporated herein by reference for all purposes.
BACKGROUND OF THE INVENTION
This invention generally relates to mattresses and mattress coverlets for preventing, reducing, and/or treating decubitus ulcers, also known as pressure sores or bedsores. More particularly, this invention concerns therapeutic mattresses or mattress coverlets capable of transferring or dissipating moisture vapor and heat from a patient's skin.
Often, patients that are bedridden or immobile can develop decubitus ulcers (pressure sores or bedsores). Such ulcers are often caused by pressure, friction, shear, moisture, and heat. Pressure results in a reduction of blood flow to the soft tissues of the body, particularly the skin. Continuous lack of blood flow, and the resultant lack of oxygen, can cause the skin to die and ulcers or sores to form. Friction and shear of the skin against the support surface can lead to skin tears and decubitus ulcers. Moisture and heat may lead to skin maceration. Other factors play a part in determining the speed with which such ulcers will form or heal including the overall health of the patient and such patient's nutritional status.
To insure normal (or, at least, relatively improved) blood flow to such areas of potentially problematic contact, patients are often turned or repositioned regularly by medical personnel. Turning or repositioning of patients, however, is not always possible, particularly where trained medical staff are not available. Additionally, repositioning can be painful and disruptive for the patient. In an effort to overcome such difficulties, numerous mattresses and mattress coverlets have been developed to more evenly distribute, across the patient's skin, the pressure generated by the weight of the body. At least two methods have been used to redistribute skin pressure. The first is the use of static supports such as foam, air or water mattresses. The second method involves the use of alternating pressure inflatable mattresses or mattress coverlets that dynamically shift the location of support under the patient. Two examples of alternating pressure inflatable surfaces are illustrated in U.S. Pat. Nos. 5,509,155 and 5,926,884, the disclosures of which are fully incorporated herein by reference.
In addition to such two methods of redistribution of skin pressure, an additional feature has been utilized to help address other of the aforementioned factors important to the healing process. In particular, a low air loss feature has been used to aid in the removal of both moisture vapor and heat thereby reducing both at the patient-bed boundary. This has been done in an effort to prevent skin maceration, keep wounds dry and to promote healing.
There have been essentially three approaches to achieving a low air loss support surface. First, relatively tiny holes can be provided in the top surface of inflatable air cells of an air mattress having a vapor-permeable top surface. Such holes allow extra air to circulate inside the mattress to assist in drying moisture vapor passing through the top surface from the patient.
Second, relatively tiny holes can be provided in the top surface of the mattress so that the air venting from the air cells can transfer through the top surface to the patient in order to remove both heat and moisture from the area immediately surrounding the patient.
Finally, a multi-layer mattress coverlet can be used wherein the top layer is perforated to allow air flowing between the top layer and a middle vapor-permeable layer to exhaust across the patient thus aiding in removing both moisture and heat from the area immediately surrounding the patient. The third layer of such a three-layer approach may be a three-dimensional fabric, which allows for additional moisture vapor to be carried away from the patient.
While each of these approaches is useful for its purpose, there are various disadvantages with these approaches and in particular, with using them individually. The first and second referenced approaches to obtaining a low air loss feature requires a large compressor pump to maintain sufficient air to inflate the air cells of the mattress. Such large compressor pumps tend to be very noisy, require high electrical consumption and generate significant heat in a relatively confined area. Such high electrical consumption, and the additional need for continuous blower operation, has, in the past, resulted in over-heating of the air used to circulate about the patient. Conversely, in the case of an elderly patient, airflow directly across their body could result in an uncomfortable reduction in body temperature or even a drying out of the skin beyond that which is helpful.
Additionally, having holes in air cells of an inflatable air system results in a support surface that will deflate if there is a loss of electrical power or if no such power supply is available. Further, having perforations in the patient-bed contact surface results in a mattress that is not fluid-proof. This allows for potential contamination of the interior of such mattress by bodily fluids, products used to treat the patient and/or products used to clean such mattress itself. All three referenced approaches fail to allow air to flow under load (i.e., underneath the patient or through the top surface to the patient's skin when supporting the weight of the patient).
Similarly, some prior art mattresses and mattress coverlets have had difficulty in controlling billowing. Billowing is the uncontrolled inflation of the upper surface of a mattress or mattress coverlet in the area immediately surrounding the outline of a patient's body when the patient lies on the mattress. In essence, the mattress or mattress coverlet fails to fully support a patient and instead seemingly envelops them when the patient's weight is applied thereto. Thus further illustrating the failure of some prior mattresses and/or mattress coverlets to fully support the patient and thus resulting in the air flow through the mattress, mattress top layer, or through the coverlet (i.e., the three aforementioned approaches) to flow around the patient, rather than flowing underneath the patient to aid in controlling moisture and heat.
With all of the above approaches, it is further unknown to have the capability to turn on or off the low air loss option while retaining through the use of powered air cells the redistribution of skin pressure feature of the mattresses or mattress coverlets. If a low air loss therapy is not desired, a different system must be utilized with an alternative controller and air cell array.
SUMMARY OF THE INVENTION
The present invention recognizes and addresses various of the foregoing limitations and drawbacks, and others, concerning the prevention and/or treatment of decubitus ulcers. It is, therefore, a principle object of the subject invention to provide an improved mattress and/or mattress coverlet for use in the prevention and treatment of decubitus ulcers. More particularly, it is a principle object of the subject invention to provide a mattress and/or mattress coverlet incorporating an air circulation system that does not exhaust its air directly across the patient.
Another more particular object of the subject invention is to provide a new air flotation mattress and/or mattress coverlet including a low air loss feature. In such context, it is a further object to provide a mattress and/or mattress coverlet wherein the low air loss feature can be turned on or off as desired for the treatment of the patient, independently of how the basic patient support surface is operated.
It is still a further object of the present invention to provide a mattress and/or mattress coverlet including a three-dimensional non-crush fabric to allow for the airflow of such a low air loss feature to flow under load.
Another general object of the subject invention is to provide a mattress capable of selectively providing either an alternating pressure inflatable support or a floatation support for the redistribution of skin pressure.
It is still a further object of the subject invention to provide a self contained external control system (ECS) including at least two pumps which are required to respectively maintain both the inflation of the mattress support and, if desired, the low air loss feature of the mattress coverlet. In such context, it is a further object of the present invention to provide a mattress or mattress coverlet capable of maintaining inflation of the patient support surface during a loss or unavailability of electrical power.
Another object of the present invention is to provide an independently usable low air loss coverlet, which may be combined with various support scenarios, such as with preexisting mattress support systems, patient positioners, and/or wheelchair/seating cushions (as a retrofit or as original equipment combined with a prior design), regardless of whether such prior systems incorporate an air powered patient support surface.
Additional objects and advantages of the invention are set forth in, or will be apparent to those with ordinary skill in the art from the detailed description herein. Also, it should be further appreciated that modifications and variation to the specifically illustrated, referenced, and discussed features, materials, or devices hereof may be practiced in various uses and embodiments of this invention without departing from the spirit and scope thereof, by virtue of present reference thereto. Such variations may include, but are not limited to, substitution of equivalent materials, means, or features for those shown, referenced or discussed, and the functional, operational, or positional reversal of various features, parts or the like.
Still further, it is to be understood that different embodiments, as well as different presently preferred embodiments, of this invention may include various combinations or configurations of presently disclosed features, or elements, or their equivalents (including combinations of features or configurations thereof not expressly shown in the figures or stated in the detailed description).
One exemplary embodiment of the present invention includes an air flotation mattress with an ECS. The support surface of such air flotation mattress may include a foam shell with a surface treatment on its upper surface. An exemplary GEO-MAT® surface treatment is illustrated in commonly owned U.S. Pat. No. 4,862,538, which is fully incorporated herein by reference. Such surface treatment aids in redistributing skin pressure. Additionally, the air floatation mattress includes a plurality of air cells running side-to-side providing the ability to sub-divide the mattress support into pre-designated zones.
Included with such an exemplary air flotation mattress may be a low air loss coverlet in accordance with the subject invention. Such air flotation mattress serves as the primary support surface offering both a flotation and alternating pressure treatment option. Such low air loss coverlet provides an option to enhance the process of removing moist warm air from the area around the skin of the patient. It achieves such function by employing a patient-contact fabric top layer possessing a high moisture vapor transfer ratio enhanced by airflow through an inner layer of the coverlet.
Such a mattress coverlet preferably comprises three layers. The first layer (on the top, facing the patient interface) is a vapor permeable layer, which allows moisture vapor and heat to travel away from the patient's body. Such moisture vapor enters the second layer, which may comprise a non-crush three-dimensional fabric, such as a specialty knit. The ECS forces air through the second (i.e., middle) layer to aid in carrying away the warm moist air. The final layer of such mattress coverlet (furthest from the patient interface) is a waterproof, vapor impermeable layer that acts as a boundary to protect the underlying mattress.
The mattress coverlet's third layer may additionally comprise a coverlet-mattress topper such as a zippered sheath for encasing a mattress. Such construction advantageously enables the coverlet to effectively function with any mattress and not just the air flotation mattress as disclosed herein. Accordingly, various embodiments of the subject invention may comprise a mattress coverlet in accordance with the subject invention, combined with a variety of underlying patient support surfaces, including a mattress, patient positioner, and/or wheelchair/seating cushion (regardless of whether pre-existing, disclosed herewith, or later developed).
Yet another exemplary embodiment of the present invention includes an air flotation mattress with an ECS. The air flotation mattress includes a plurality of air cells running head-to-foot. A foam shell topper with foam bolsters and foam sides running the length of the mattress on either side forms the air flotation mattress. At each end of the air flotation mattress and capping the foam bolsters and sides is either a foam header or foam footer, which along with the bolsters form a cavity in the mattress. This cavity is for positioning of the air cells.
Included with such an exemplary air flotation mattress may be a low air loss coverlet in accordance with the subject invention. Such air flotation mattress serves as the primary patient support surface. Such low air loss coverlet provides an option to enhance the process of removing moist warm air from the area around the skin of the patient. It achieves such function by employing a patient-contact fabric top layer possessing a high moisture vapor transfer ratio enhanced by airflow through an inner layer of the coverlet.
Such a mattress coverlet preferably comprises two layers. The first layer (on the top, facing the patient interface) is a vapor permeable layer, which allows moisture vapor and heat to travel away from the patient's body. Such moisture vapor enters the second layer, which may comprise a non-crush three-dimensional fabric. The ECS forces air through the second layer of such mattress coverlet to aid in carrying away the warm moist air.
The air floatation mattress additionally comprises a multi-layer mattress topper comprising three layers. The first layer of such multi-layer mattress topper (adjacent such a mattress coverlet) is a waterproof, vapor impermeable layer that performs as a boundary to protect the underlying mattress. The second layer may comprise a non-crush three-dimensional fabric. The ECS forces air through the second (i.e., middle) layer in addition to providing airflow through the second layer of such a companion low air loss mattress coverlet.
The multi-layer mattress topper's third layer may comprise a waterproof, vapor impermeable layer that performs as a boundary to protect the underlying mattress. The topper's third layer serves as the basis for a zippered sheath for encasing such a foam-based portion of the mattress. The multi-layer mattress topper's first and third layers are welded around their perimeter so as to secure their construction.
Similarly, the two layers of such a coverlet are sewn together around their perimeter and may utilize an elasticized band there-around for securing the coverlet to the mattress. Such construction advantageously enables the coverlet to effectively function with any mattress and not just the air flotation mattress as disclosed herein. Accordingly, various embodiments of the subject invention may comprise a mattress coverlet in accordance with the subject invention, combined with a variety of underlying patient support surfaces, including a mattress, patient positioner, and/or wheelchair/seating cushion (regardless of whether pre-existing, disclosed herewith, or later developed).
BRIEF DESCRIPTION OF THE DRAWINGS
A full and enabling disclosure of the present invention, including the best mode thereof, directed to one of ordinary skill in the art, is set forth in the specification, which makes reference to the appended figures, in which:
FIG. 1 is a bottom elevational view of an exemplary air flotation mattress in accordance with the subject invention with exemplary foam bolsters, sides, header, and footer, and individual air cell features of such exemplary mattress running side-to-side;
FIG. 2 is a cross-sectional view of the exemplary air flotation mattress shown in FIG. 1 , taken along line 2 / 5 - 2 / 5 in FIG. 1 , illustrating an exemplary foam shell topper ( 20 ) with a specific surface treatment, a foam header and footer, and including a foam block with a hole there-through for connection of air passageways to the exemplary air cells of the mattress;
FIG. 3 is a cross-sectional view of the exemplary air flotation mattress shown in FIG. 1 , taken along line 3 - 3 in FIG. 1 , illustrating the construction of an exemplary foam shell of the mattress including an exemplary foam shell topper ( 20 ), bolsters and sides.
FIG. 4 is a top elevational view of the construction of an exemplary mattress coverlet showing numerous spot welds used in accordance with the subject invention to aid in the prevention of billowing, and showing exemplary air exhaust ports that provide an exit for the air flowing through the mattress coverlet during low air loss operation;
FIG. 5 is a cross-sectional view of the exemplary air flotation mattress shown in FIG. 1 , taken along line 2 / 5 - 2 / 5 in FIG. 1 , showing an exemplary three-layer mattress coverlet in accordance with the subject invention and otherwise illustrating exemplary foam shell topper ( 20 ), header and footer, and air cells of the mattress;
FIG. 6 is a schematic view of exemplary air flotation mattress air cell zones and the ECS which controls their inflation/deflation, and which in accordance with the subject invention separately provides for independent operation of the subject low air loss feature;
FIG. 7 is a schematic view of an exemplary arrangement of air flotation mattress air cells and their respective inflation tubing;
FIG. 8 is an exemplary internal schematic view of an ECS in accordance with the subject invention showing the two exemplary pumps used to respectively provide air for the air flotation mattress and the mattress coverlet, and showing an exemplary rotary valve which may be practiced in accordance with the subject invention;
FIG. 9 is an external view of an exemplary ECS showing exemplary hanging hooks and rubber feet for supporting the ECS respectively on either the bedframe or the floor, as well as exemplary connection points for air flow passageways;
FIG. 10 is a bottom elevational view of an exemplary air flotation mattress in accordance with the subject invention with exemplary foam bolsters, sides, header, and footer, and individual air cell features of such exemplary mattress running head-to-foot; and
FIG. 11 is a cross-sectional view of the exemplary air flotation mattress shown in FIG. 10 , taken along line 11 - 11 in FIG. 10 , showing an exemplary multi-layer mattress coverlet and a multi-layer mattress topper in accordance with the subject invention and otherwise illustrating an exemplary foam shell topper ( 20 ), header and footer, and such head-to-foot air cells of the mattress.
Repeat use of reference characters throughout the present specification and appended drawings is intended to represent same or analogous features, aspects, or elements of the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Reference will now be made in detail to a presently preferred embodiment of the invention, an example of which is discussed in conjunction with the accompanying drawings. Such example is provided by way of an explanation of the invention, not limitation thereof. In fact, 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 and scope thereof. For instance, features illustrated or described as part of one embodiment can be used on or in another embodiment to yield a still further embodiment. Still further, variations in selection of materials and/or characteristics may be practiced, to satisfy particular desired user criteria. Thus, it is intended that the present invention cover such modifications and variations as come within the scope of the present features and their equivalents.
As referenced above, the present invention is particularly concerned with, in exemplary broad terms, an air flotation mattress 100 and mattress coverlet 200 for the prevention and treatment of decubitus ulcers (pressure sores and bedsores). The air flotation mattress 100 provides a user selectable flotation or alternating pressure support surface. The mattress coverlet 200 provides a low air loss feature that can be turned on or off as desired by the user (here, broadly referencing a patient or person resting on such coverlet and/or a caregiver therefore).
As shown in the bottom elevational view of FIG. 1 , the air flotation mattress 100 is formed by a foam shell topper 20 (best seen in FIGS. 2 and 3 ) with foam bolsters 22 and foam sides 24 running the length of the mattress 100 on either side. At the respective ends of the air flotation mattress 100 and capping the foam bolsters and sides 22 and 24 , respectively, are a foam header 26 and foam footer 28 , which along with the bolsters 22 form a cavity in the mattress 100 . This cavity is for positioning of air cells, such as the exemplary grouped (i.e., zoned) air cells 30 , 32 , 34 and 36 .
The cavity formed by the foam bolsters 22 , header 26 , and footer 28 , contains the air cells 30 , 32 , 34 and 34 . The air cells 30 , 32 , 34 , and 36 are essentially inflatable air bladders connected directly to an external control system 300 via passageways 76 , 78 , and 80 (see FIGS. 6 and 7 and corresponding discussion) for their inflation/deflation. Such air cells 30 , 32 , 34 , and 36 may be operated to provide the primary support surface for the patient.
There are twelve exemplary air cells 30 , 32 , 34 and 36 . Other numbers thereof (or none at all) may be practiced in various embodiments of the subject invention. Such air cells 30 , 32 , 34 , and 36 are divided into four separate zones. The first exemplary zone (hereinafter the head zone) comprises three air cells 30 each of which may be maintained in an equal state of inflation/deflation relative to each other. The second exemplary zone (hereinafter the foot zone) comprises three air cells 36 each of which may be maintained in an equal state of inflation/deflation relative to each other.
Exemplary zones three and four together (all of the remaining cells) comprise the central or torso zone. Each of zones three and four comprise an alternating set of three air cells 32 and 34 , respectively, within the torso zone. The torso zone (i.e., all six air cells 32 and 34 ) may be maintained at an equal state of inflation/deflation. As part of the capability of air flotation mattress 100 to provide alternating pressure support, zones three and four can alternate between specific states of inflation/deflation, thus dynamically changing the location of the support for the patient's torso. As part of the ECS 300 , a firmness control may be provided which allows the user to specify the level of inflation of the air cells 30 , 32 , 34 , and 36 both during the flotation and alternating pressure support treatment cycles.
As represented to those of ordinary skill in the art by the cross-sectional view of FIG. 2 , the foam shell topper 20 of such air flotation mattress 100 may have on its upper surface 38 a GEO-MATT® surface treatment to aid in redistributing skin pressure. The bottom surface 40 of such foam shell topper 20 may be cut to provide predetermined ridges 42 running side-to-side to act as retainers for such air flotation mattress' respective air cells 30 , 32 , 34 and 36 .
In order for the mechanical connections between the ECS 300 and both the mattress 100 and mattress coverlet 200 to be made an exemplary foam block 44 with a hole there-through may be located at the end of one foam bolster and side 22 and 24 , respectively.
As best seen in the cross-sectional views of FIGS. 2 and 3 , the foam shell topper 20 extends across almost the entire width and substantially the entire length of such mattress 100 . The foam shell topper's 20 width extends from each foam side 24 . Similarly, the topper's 20 length is terminated only by the foam header 26 and the foam footer 28 . The bolsters 22 act as both supports for the connection between the topper 20 and the sides 24 and as retainers for the air cells 30 , 32 , 34 , and 36 .
The exemplary mattress coverlet 200 is comprised of three separate layers. As seen in FIGS. 4 and 5 , the first layer 46 of such mattress coverlet 200 is a sheet of waterproof, vapor permeable material. It is designed to allow moisture-vapor and heat from the patient's body or relatively immediately adjacent thereto to pass through to the second (i.e., middle) layer 48 . The second layer 48 of such mattress coverlet 200 is a non-crush three-dimensional fabric that is moisture resistant and vapor and air permeable. It is through this middle layer 48 of the mattress coverlet 200 that the low air loss feature of the present invention forces air, which aids in removing the warm moist air generated by the patient. An exemplary depiction of the direction of airflow through the mattress coverlet 200 is indicated by exemplary airflow 50 .
In accordance with the present preferred embodiment, the third layer 52 of the mattress coverlet 200 is a waterproof, vapor impermeable sheet. This final layer 52 acts as a retainer of the warm moist air generated by the patient and transmitted through the first layer 46 to the second layer 48 . It maintains the warm moist air within the second layer 48 so it can be removed by the low air loss airflow (as indicated in FIG. 5 by exemplary air flow 50 ). Similarly, it acts as a boundary to prevent heat transfer from the air within the air flotation mattress's air cells 30 , 32 , 34 , and 36 , to the patient. Such third layer 52 may additionally comprise a zippered coverlet-mattress topper for encasing a mattress.
In other embodiments, an exemplary coverlet 200 in accordance with the subject invention may be modularly applied to other supports including mattresses, wheelchair/seating cushions, and/or patient positioners (whether air powered, pre-existing, disclosed herewith, or later developed). Several exemplary such support surfaces can be found in commonly owned U.S. Pat. No. 5,568,660 to Raburn et al; U.S. Pat. No. 5,797,155 to Maier et al.; and Des. 355,488 to Hargest et al., the disclosures of which are full incorporated herein by reference.
Some former mattress coverlets have suffered from the problem of billowing. As further represented in the top elevational view of present FIG. 4 , in accordance with the present invention the occurrence of billowing may be reduced through the use of spot welds 54 of the first layer 46 to the third layer 52 in locations throughout the surface of the mattress coverlet 200 . In making such spot-welds 54 , small sections of the material of the second layer 48 of the mattress coverlet 200 have been removed to allow for an unimpeded welding of the first and third layers ( 46 and 52 , respectively).
The mattress coverlet 200 is preferably constructed of a first layer 46 comprising a polyurethane coated polyester which is perimeter welded 58 to the third layer 52 . Along the head end of the coverlet 200 , where the first and third layer 46 and 52 , respectively, are connected the perimeter weld 58 is intermittent to provide for exhaust air ports 60 . It is through these exhaust air ports 60 that the warm moist air trapped within the second layer 48 is disposed.
The third layer 52 of the coverlet 200 preferably comprises a polyurethane coated nylon so as to be moisture and vapor impermeable. The second (i.e., middle) layer 48 is preferably a non-crush three-dimensional fabric. The third layer 52 additionally may have skirt welds 63 along substantially the entire perimeter of the material.
As best seen in FIG. 5 , in the presently preferred exemplary embodiment, the third layer 52 forms a coverlet-mattress mattress topper, which may encase a mattress. The coverlet-mattress topper comprises an upper (i.e., the third layer 52 of the mattress coverlet 200 ) and lower sheet connected to two side panels, a head panel, and a foot panel in a bag-like configuration. Around the perimeter of the coverlet-mattress topper, running along the middle of the side, head, and foot panels is a zipper 56 for encasing a mattress within the topper. It is this coverlet-mattress topper that may maintain the mattress coverlet 200 in place despite the movement of the patient while on the support surface.
As will be clear to those of ordinary skill in the art from FIGS. 6-9 and their associated discussion, the air flotation mattress 100 and the mattress coverlet 200 are regulated by the ECS 300 . The exemplary ECS 300 comprises two pumps 62 and 64 , a regulator 66 , a rotary valve 68 , a single quick-disconnect connector 70 for connection of air passageway 72 to the mattress coverlet 200 , and three quick-disconnect connectors 74 for connecting air passageways 76 , 78 , and 80 to the air flotation mattress air cells 30 , 32 , 34 , and 36 . Air is provided to the head and foot zones via air passageway 76 and is provided to zones three and four (i.e., the central or torso zone) via air passageways 78 and 80 , respectively. The ECS features are preferably all within a stand-alone housing 82 . The housing 82 is provided with rubber feet 84 for positioning the housing on the floor and with hooks 86 for hanging the ECS 300 from a bedframe.
The ECS 300 has two pumps 62 and 64 for separate operation of the air flotation mattress 100 and the mattress coverlet 200 . The first pump 62 operates the air flotation mattress 100 . It is preferably a pump which provides quiet operation and a quick response to an inflation request. The second pump 64 functions to provide air for the low air loss system in the mattress coverlet 200 . The low air loss system pump 60 64 is preferably a pump which provides a higher air flow rate for the mattress coverlet 200 than would be provided by the air flotation mattress pump 62 .
The first pump 62 operates in connection with a regulator 66 and a rotary valve system 68 to provide air for the air flotation mattress 100 . In operation of this exemplary embodiment, the air provided to the head and foot zones (i.e., exemplary air cells 30 and 36 , respectively) is delivered through a first passageway 76 . This first passageway 76 serves to interconnect the head and foot zones to insure consistent inflation/deflation. The air provided to the torso zone, exemplary air cells 32 and 34 , respectively, enters through separate passageways 78 and 80 , respectively. With each of the passageways 78 and 80 associated with the torso zone are control valves 88 to either allow inflation/deflation or to maintain the current state of inflation/deflation of the air cells 32 and/or 34 . Such valves 88 are separately operable which allows for the provision of an alternating pressure support surface within the air flotation mattress 100 . When the control valves 88 within passageways 78 and 80 are set to mimic the inflation/deflation of the head and foot zones, the air flotation mattress 100 is able to provide a static support surface. The construction of such valves 88 and pumps 62 and 64 are well known to those of ordinary skill in the art, and details thereof form no particular part of the subject invention.
The second pump 64 may be operated in accordance with the subject invention to provide a continuous flow of air to the low air loss mattress coverlet 200 . As shown in FIG. 4 , the first layer 46 of the mattress coverlet 200 contains air exhaust ports 60 for the expulsion of the low air loss air flow through the mattress coverlet 200 . An air input port (not shown) is preferably generally located at the foot end of the mattress coverlet 200 and the air exhaust ports 60 are preferably located at the opposite end of the mattress coverlet 200 . However, one of ordinary skill in the art will recognize that alternative configurations of such features fall within the scope and spirit of the present invention.
In operation, the ECS 300 functions to provide the user the widest variety of treatment options. The user can select from either a static pressure support surface, in which the air flotation mattress 100 maintains a consistent inflated state across all zones, or an alternating pressure support surface, in which the head and foot zones maintain a consistent inflation state and zones three and four within the torso zone dynamically fluctuate between opposed states of inflation/deflation, respectively. In addition to the choice of support surface function to be provided by the air flotation mattress 100 , the ECS 300 allows the user to choose whether or not to allow the operation of the low air loss mattress coverlet 200 to aid in removing warm moist air away from the patient's skin. It is this wide range of user (and/or caregiver) choice in treatment methods and its modularity that allows the system, the air flotation mattress 100 , the low air loss mattress coverlet 200 and the ECS 300 , to be so flexible.
Additionally, in emergency operations, the system is designed to be as flexible as possible in order to aid in the treatment of the patient. Should the need arise to quickly provide a more sturdy surface for the patient, such as in the case where a patient suffers a heart attack and requires chest compression, the present invention provides the user three options: inflate the air flotation mattress 100 fully by utilizing the static support surface feature, terminate the operation of the pumps and allow the air flotation mattress to deflate, or to utilize the quick-disconnect connectors 74 between the ECS 300 and the air passageways 76 , 78 , and 80 to allow for complete deflation of the air flotation mattress 100 .
Similarly, when there is a loss of power to the ECS 300 , the system is designed to retain its functionality to aid in the treatment of the patient. The air flotation mattress is designed to maintain the inflation pressure within the air cells 30 , 32 , 34 , and 36 . It performs such function by allowing the pressure across all the cells 30 , 32 , 34 , and 36 to even out and become consistent (as when utilizing the static pressure support surface feature). The system is able to maintain the air within the cells through the use of several three-way control valves 88 which open to allow communication between the air cells 30 , 32 , 34 , and 36 and through the use of a two-way control valve 90 which closes to deny an exit path for the air already in the system.
An alternative presently preferred embodiment may comprise an air flotation mattress 100 with a multi-layer mattress topper 400 and/or mattress coverlet 200 for the prevention and treatment of decubitus ulcers (pressure sores and bedsores). The mattress coverlet 200 provides a low air loss feature that can be turned on or off as desired by the user (here, broadly referencing a patient or person resting on such coverlet and/or a caregiver therefor).
As best seen in FIG. 10 , a foam shell topper 20 with foam bolsters 22 and foam sides 24 running the length of the mattress 100 on either side forms the air flotation mattress 100 . At the respective ends of the air flotation mattress 100 and capping the foam bolsters and sides 22 and 24 , respectively, are a foam header 26 and foam footer 28 , which along with the bolsters 22 form a cavity in the mattress 100 . This cavity is for positioning of air cells 35 . Unlike the above-preferred embodiment, the air cells 35 of the presently preferred embodiment run head-to-foot with such cavity.
As above, the cavity formed by the foam bolsters 22 , header 26 , and footer 28 , contains the air cells 35 . The air cells 35 are essentially inflatable air bladders connected directly to an external control system 300 as above described for their inflation/deflation. Such air cells 35 are operated to provide the primary support surface for the patient.
As represented to those of ordinary skill in the art by the cross-sectional view of FIG. 2 , the foam shell topper 20 of such air flotation mattress 100 may have on its upper surface 38 a GEO-MATT® surface treatment to aid in redistributing skin pressure. The bottom surface 40 of such foam shell topper 20 may be alternatively cut to provide predetermined ridges 42 running head-to-foot to act as retainers for such air flotation mattress' respective air cells 35 .
In accordance with this alternative presently preferred embodiment, the mattress coverlet 200 may be additionally sheathed in a multi-layer mattress topper 400 . The first layer 51 of the multi-layer mattress topper 400 is a waterproof, vapor impermeable sheet. The second (i.e., middle) layer 53 may comprise a non-crush three-dimensional fabric, such as a knit, cloth, polymeric film, foam or extruded woven fibers. Finally, the third layer 52 may additionally comprise a waterproof, vapor impermeable sheet for protection of the underlying mattress coverlet 200 . Such third layer 52 may additionally comprise a zippered sheath for encasing the mattress coverlet 200 .
The exemplary mattress coverlet 200 is comprised of two separate layers. As seen in FIG. 11 , the first layer 47 of such mattress coverlet 200 is a sheet of waterproof, vapor permeable material. It is designed to allow moisture-vapor and heat from the Patient's body or relatively immediately adjacent thereto to pass through (such as perforations or relatively small holes 59 in layer 47 ) to the second layer 49 . The second layer 49 of such mattress coverlet 200 is a non-crush three-dimensional fabric that is moisture resistant and vapor and air permeable. It is through this middle layer 49 of the mattress coverlet 200 that the low air loss feature of the present invention forces air, which aids in removing the warm moist air generated by the patient. An exemplary depiction of the direction of airflow through the mattress coverlet 200 is indicated by exemplary airflow 50 .
The two layers 47 and 49 of the mattress coverlet 200 are sewn together around their perimeter. Various methods of attaching such a coverlet 200 may be utilized. For example, said coverlet 200 may be formed with an elastic band sewn around its outer perimeter so as to envelop such a mattress 100 as would a fitted sheet.
In the case of a “fitted-sheet” style coverlet 200 , the entirety of the outer perimeter of the first and second layers 47 and 49 , respectively, may be sewn together. In such an embodiment, the forced air from the ECS 300 along with the warmth and moisture from the air in the second layer 49 of the coverlet may escape around the entire perimeter through the loose friction fit of the elastic band of the coverlet 200 . As described above, this alternative presently preferred embodiment may be regulated by an ECS 300 . The two pumps 62 and 64 of the ECS 300 serve to provide the airflow for both the primary patient support (i.e., the mattress 100 and the airflow through the middle layer 53 of the multi-layer mattress topper 400 ) and for the mattress coverlet 200 . The method of connection of the ECS 300 , its operation and features is as discussed in detail above.
As in other embodiments, the exemplary coverlet 200 in accordance with the subject invention may be modularly applied to other supports including mattresses, wheelchair/seating cushions, and/or patient positioners (whether air powered, pre-existing, disclosed herewith, or later developed).
It is to be understood that the present invention may be practiced in conjunction with combinations of additional features, not necessarily shown or discussed in detail. In particular, the size, shape and support characteristics of the air flotation mattress 100 , the multi-layer mattress topper 400 and/or the mattress coverlet 200 may vary as desired or as needed. Additionally, both the mattress coverlet 200 and the multi-layer mattress topper 400 may be utilized with mattresses of various size and shape (regardless of whether air powered, pre-existing, disclosed herewith, or later developed), in addition to being useful with other support devices such as patient positioner and wheelchair/seating cushions. All such variations, as would be understood by one ordinarily skilled in the art are intended to fall within the spirit and scope of the present invention. Likewise, the foregoing presently preferred embodiments are exemplary only, and their attendant descriptions are similarly intended to be examples of the present invention rather than words of limitation. | An air inflatable mattress and mattress coverlet are provided for the prevention and treatment of decubitus ulcers (i.e., pressure sores or bedsores). The mattress incorporates a user selectable static or alternating air powered support surface for more uniformly redistributing pressure exerted on a patient's skin. The mattress coverlet encompasses a low air loss feature independent of the mattress's user selectable air powered support surface. Such low air loss feature provides a patient contact surface exhibiting a high moisture vapor transfer ratio in conjunction with a forced air flow to aid in reducing the moisture and heat near the patient's body. Both the mattress and mattress coverlet are driven by an external control system which houses the user controls, as well as the necessary pumps, regulators, and valving. | 0 |
This invention relates generally to the accessories for automotive trucks. More specifically it relates to air deflectors.
BACKGROUND OF THE INVENTION
It is well known that the high, wide front wall of a truck body creates a considerable drag on the vehicle's forward travel, as this wall strikes flat against the air in front hereof. This drag slows up the vehicle's forward progress, so that more fuel must be burned in order to keep the truck travelling at an efficient rate of speed. This increased use of fuel is objectionable, because fuel is expensive, and this situation is accordingly in need of an improvement.
SUMMARY OF THE INVENTION
Therefore, it is a principal object of the present invention, to provide a stream-lined air deflector which is mountable upon the narrower and lower roof of the truck cab, and which deflects the forward air sidewardly and upwardly away from this truck body front wall, so as to reduce the air resistance in front as the vehicle travels ahead along a road.
Another object is to provide an air deflector which is adjustable in stream-line shape, so as to suit vehicles of different sizes of truck body front wall, in order that it is a perfect shape to deflect the front air just enough so as to clear the body front wall and pass around the sides and over a top of the truck body as the vehicle travels ahead.
Yet a further object is to provide an air deflector which accordingly is adjustable in stream-line shape so as to be set up for the usual cruising speed of the vehicle, in order that the approaching front air is deflected at a speed rate so that the deflected air clears the edges of the forwardly moving body front wall as it advances ahead.
Yet a further object is to provide an air deflector which accordingly by being adjustable, prevents the use of an excessive over-stream-lined deflector for the specific vehicle, such as which, while deflecting front air, would be at too great an inclined angle, and thus itself came a drag.
Further objects of the invention will appear as the description proceeds.
To the accomplishment of the above and related objects, this invention may be embodied in the form illustrated in the accompanying drawings, attention being called to the fact, however, that the drawings are illustrative only, and that changes may be made in the specific construction illustrated and described within the scope of the appended claims.
BRIEF DESCRIPTION OF THE DRAWING FIGURES
The figures on the drawings are briefly described as follows:
FIG. 1 is a side perspective view of the invention installed upon a truck cab.
FIG. 2 is a rear perspective view of the frame structure of one embodiment of invention.
FIG. 3 is a plan view thereof, shown with the covering panels removed.
FIG. 4 is a side cross sectional view taken on line 4--4 of FIG. 6 and showing another embodiment.
FIG. 5 is a fragmentary cross sectional view taken on line 5--5 of FIG. 4. FIG. 6 is a fragmentary bottom view of the device, and showing principally only the moving parts of the mechanism.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now to FIG. 1 and 4-6 of the drawings in greater detail, the reference numeral 10 represents a retractable air deflector according to the present invention, and which may be installed upon a roof 11 of a truck cab 12 in order to deflect air 13 upwardly at 13', preventing the air from striking the front wall 14 of the truck body 15.
The air deflector is constructed with a V-shaped base frame shown generally at 16 which is secured directly on the cab roof, and is positioned so that an apex point 17 thereof extends forwardly toward the approaching air 13. The frame is comprised of two straight side rails 18 which junction at the point 17, and a lower flat panel 19 is pivoted along an upper edge of each rail by means of hinges 20. Each side rail is comprised of an inclined side wall 21 integral with upper and lower flanges 22 and ribs 23 between the flanges. The panels 19 are each generally triangular in shape (as shown in FIG. 9) with one corner 24 of each being at the apex of the frame, and one longitudinal side edge 25 of one panel 19 abutting the edge 25 of the other panel 19 when both of the panels are pivoted into a common flat horizontal plane. A cross beam 26 is fixedly secured between the side rails 18.
The panels 19 are are pivotable upwardly from the above-described horizontal plane position by means of a captive screw mechanism 27, which is supported on the cross beam 26 and on a slidable block 28.
The mechanism 27 includes a threaded rod 29 having an enlarged head 30 at one end for being held axially inside the apex 31 of the frame, while the rod is free to be rotated manually by means of a handle 32 affixed on the rod opposite end. The block 28 is threaded on the rod 29 so as to be slidable along the rod when the handle 32 is turned. A pair of braces 33 are pivotally attached at one end on the block 28, and the other end of braces are pivotally attached at 34 to an underside of each panel 19 so as to cause the panels to be raised or lowered a selected distance, as desired.
A central panel unit 35 rests on top of the two panels 19, so as to cover the gap 36 between the edges 25 of the two panels 19. The panel unit comprises a triangular, flat, central panel 37 pivotally attached along two side edges to an upper pair of triangular, flat, side panels 38 by means of hinges 39. One side edge 40 of each side panel 38 is rounded so as to slide upon the upper side of the panels 19.
A single brace 41, pivotally attached at one end to the block 28, is pivotally supported at its opposite end in a slot 42 of a bracket 43 secured to an underside of the central panel 37, so that the panel unit 35 is likewise raised or lowered together with the panels 19. An apex of the panel unit is pivoted in a recess 44 of the apex 31 and additionally may be attached thereto by a hinge 45.
A pair of auxiliary braces 46 are additionally pivotally attached to the cross beam 26 and slidable along an intermediate portion of the brace 41, for strengthening purposes.
The central panel unit 35 includes a clip 47 on an underside of each side panel 38 for clipping around a rear edge 48 of the panels 19 which slide in the clips. Additionally a rearward projection 49, affixed to each panel 19, is slidable in a grooved bracket 50 affixed to an underside of the central panel 37. The clips 47 and bracket 50 secure the assembly from breaking up in a high wind. The block 53 can be used to fix the device onto the roof, using any well known mechanism. Other attaching mechanisms can be used as well.
FIGS. 2 and 3 illustrate an alternate design 10' having a slight variation in the actual construction of the retractable air deflector, however, the same, above-described operational structure is included therein. In this embodiment, most items are similar to that of the previous embodiment described. However, the hinges 20' are localized at a particular location, and the brace arrangement 4l', 43', 54 and 55 form a slightly different embodiment which effectively serves to operate in a similar manner as the first embodiment. There are two arms 41' in this embodiment, and a continuous bar arrangement 43' rather than the separate slide connectors 43, in which the ends of the arms 41' pivot on 55 within the brace 54. Other items are substantially identical as the first embodiment and are so indicated by reference numeral.
In operative use, it is now evident that the air 13 struck by the air deflector is deflected as air stream 13' that passes over a top or around the sides of the truck body instead of striking the body front wall 14.
While certain novel features of this invention have been shown and described and are pointed out in the annexed claims, it will be understood that various omissions, substitutions and changes in the forms and details of the device illustrated and in its operation can be those skilled in the art with out departing from the spirit of the invention. | An air deflector mountable upon a truck cab roof so as to deflect air away from a front of the truck body; the deflector including a mechanism to angularly adjust its side and upper surfaces for full air deflection with minimum drag. | 1 |
FIELD OF THE INVENTION
The invention relates to an energy efficient, environmentally favourable process for the preparation of brominated rubbers, in particular bromobutyl rubber, that uses a common medium for both solution polymerization and subsequent bromination of the rubber and which further exhibits an enhanced bromine usage due to the use of an oxidizing agent. More particularly, the invention relates to a process that employs a common aliphatic medium for both solution polymerization and bromination of rubber in the presence of a brominating agent and an oxidizing agent with intermediate removal of un-reacted monomers.
BACKGROUND
The term “butyl rubber” as used herein generally means and encompasses co-polymers of C 4 to C 7 isoolefins, C 4 to C 14 conjugated dienes and optionally other co-polymerizable monomers, if not defined otherwise. The term “bromobutyl rubber” as used herein generally means and encompasses brominated butyl rubbers if not defined otherwise. An illustrative and preferred example of butyl rubber is a rubber obtained by co-polymerization of isoprene and isobutylene, which is hereinafter also referred to as IIR. Its brominated analogue is also referred to as BIIR.
In the conventional process for producing bromobutyl rubber (BIIR), isobutylene and isoprene monomers are first polymerized in a polar halohydrocarbon medium, such as methyl chloride with an aluminum based initiating system, typically either aluminum trichloride (AlCl 3 ) or ethyl aluminum dichloride (EtAlCl 2 ). The butyl rubber does not appreciably dissolve in this polar medium, but is present as suspended particles and so this process is normally referred to as a slurry process. Residual monomers and polymerization medium are then steam stripped from the butyl rubber, before it is dissolved in a bromination medium, typically a non-polar medium such as hexane. The bromination process ultimately produces the final brominated product. The conventional process therefore employs separate polymerization and bromination steps employing two different media. The use of a polar medium for polymerization and a non-polar medium for bromination necessitates intermediate stripping and dissolving steps and is inefficient from an energy point of view.
The step of separating the monomers and methyl chloride from the butyl rubber is conducted before bromination in order to avoid the formation of highly toxic byproducts from the reaction of bromine with residual monomers. The normal boiling points of the components used in the process are: methyl chloride, −24° C.; isobutylene, −7° C.; and isoprene, 34° C. Any stripping process that removes the heavier of the residual monomers (isoprene) will also remove essentially all of the methyl chloride and isobutylene. The process of removing all of the un-reacted components from the rubber slurry requires significant amounts of energy. The greater molecular weight (and therefore higher boiling point) of the brominated monomers also precludes the removal of these species following the bromination process.
Solution processes for the polymerization of butyl rubber have been known for many years and are practiced commercially in Russia. An example of the solution process is described in CA 1,019,095, which discloses the use of iso-pentane as the preferred polymerization medium. The polymers produced using the above process are non-halogenated. Although bromination could theoretically take place in iso-pentane, the presence of residual monomers (isobutylene and isoprene) would lead to formation of the afore-mentioned undesirable by-products during bromination. The removal of the unreacted monomers is the challenge for such a process and has not been resolved yet. Although it would be desirable to remove the monomers by distillation, the boiling point of iso-pentane (28° C.) is lower than that of the heavier residual isoprene monomer (34° C.), therefore this kind of separation is impossible. Even if pure n-pentane (boiling point 36° C.) were used as the medium, the difference in boiling points would be insufficient to allow effective removal of the isoprene using distillation techniques. As a result, the residual monomers and medium would all have to be stripped together from the butyl rubber, as in the slurry process, with the rubber being subsequently re-dissolved for bromination. This is, in fact, more energy intensive than bromination from the conventional slurry process. The use of iso-pentane as a common medium for producing bromobutyl rubber (BIIR) is therefore not practical using the conventional solution process.
It is known in the art to use hexane i.e. a C6 medium as a polymerization medium in the solution process. However, the viscosity of a polymer solution is strongly dependent upon the viscosity of the medium used. Because the viscosity of a C6 medium is much higher than that of a C5 medium, for a given molecular weight and polymer solids level, the resulting viscosity of the polymer solution is also much higher. This limits polymer solids content to relatively low levels when C6 is used as a solvent, since otherwise the solution becomes too viscous for good heat transfer, pumping and handling. The overall economics of a process depend strongly on the level of polymer solids in the solution or suspension emerging from the polymerization reactor; higher solids levels mean higher conversion and improved economics. In order to make material having a sufficiently high molecular weight for commercial purposes, it is necessary in butyl polymerization to employ relatively low temperatures, often less than −80° C. These low temperatures exacerbate the problem of high solution viscosity and lead to even lower solids levels. In the solution process, it is therefore quite difficult to achieve an economic solids level (conversion) at the desired temperature (molecular weight) when using hexane as a solvent due to high viscosity.
In U.S. Pat. No. 5,021,509 a process is disclosed whereby product from the conventional slurry polymerization process is mixed with hexane to produce a crude rubber solution or cement. The hexane is added to the methyl chloride—rubber slurry after exiting the polymerization reactor in order to dissolve the rubber in hexane while still finely divided and suspended in the methyl chloride/monomer mixture. A distillation process is then used to remove methyl chloride and residual isobutene and isoprene monomers for recycle, leaving just the rubber in a hexane solution ready for halogenation. This so-called “solvent replacement” process still requires that all of the original media left with the rubber after the polymerization stage are removed. The energy requirement is essentially the same as in the conventional process. No common solvent is employed for both polymerization and bromination.
In addition to unfavourable energy consumption, a further major inefficiency of known processes for the preparation of bromobutyl rubbers is that the theoretical fraction of bromine present in the reaction mixture which can be introduced into the polymer is at maximum 50% of the theory, and the actual utilization observed in commercial plants is usually less than 45%. Most of the remaining bromine is lost due to formation of hydrogen bromide as a by-product which, under normal conditions, does not brominate the polymer any further. Hydrogen bromide is subsequently neutralized with a basic material such as sodium hydroxide solution and washed off the bromobutyl rubber, as described for example in U.S. Pat. No. 5,077,345. As a consequence, large amounts of diluted alkali metal bromides or alkaline earth metal bromides are disposed off every year.
A known method to enhance the bromine utilization during butyl rubber bromination involves the application of at least 0.5 mol per mol of brominating agent of an oxidizing agent such as hydrogen peroxide or alkali or alkaline earth metal hypochlorite, optionally in the presence of an emulsifier which reoxidizes the hydrogen bromide back to elemental bromine. The regenerated bromine is thus available for further bromination of butyl rubber, thereby significantly increasing the bromine utilization. Such processes are disclosed for example in U.S. Pat. Nos. 3,018,275, 5,681,901 and EP 803 517 A.
EP 709 401 A discloses a process for improving the bromination efficiency in rubber bromination processes by carrying out the bromination reaction in the presence of elemental bromine and an aqueous solution of an organic azo compound such as azodiisobutyronitrile and/or an alkali or alkaline earth metal hypochlorite.
However, there still remains a need for an efficient, environmentally favourable process for the preparation of bromobutyl rubbers that significantly reduces energy and raw material consumption and operates within an acceptable range of viscosities in order to allow high rubber solids levels at the desired molecular weight. The process must further allow separation of the residual monomers from the solvent prior to halogenation in order to mitigate the formation of undesirable by-products.
SUMMARY OF THE INVENTION
There is now provided a process for the preparation of brominated rubbers comprising at least the steps of:
a) providing a reaction medium comprising
a common aliphatic medium comprising at least 50 wt.-% of one or more aliphatic hydrocarbons having a boiling point in the range of 45° C. to 80° C. at a pressure of 1013 hPa, and a monomer mixture comprising at least one isoolefin monomer, at least one multiolefin monomer and either no or at least one other co-polymerizable monomer in a mass ratio of monomer mixture to common aliphatic medium of from 40:60 to 99:1, preferably from 50:50 to 85:15 and even more preferably from 61:39 to 80:20;
b) polymerizing the monomer mixture within the reaction medium to form a rubber solution comprising a rubber polymer which is at least substantially dissolved in the medium comprising the common aliphatic medium and residual monomers of the monomer mixture; c) separating residual monomers of the monomer mixture from the rubber solution to form a separated rubber solution comprising the rubber and the common aliphatic medium, d) brominating the rubber in the separated rubber solution using a brominating agent which is at least partially regenerated by an oxidizing agent.
The scope of the invention encompasses any possible combination of definitions, parameters and illustrations listed herein whether in general or within areas of preference.
As used herein the term “at least substantially dissolved” means that at least 70 wt.-%, preferably at least 80 wt.-%, more preferably at least 90 wt.-% and even more preferably at least 95 wt.-% of the rubber polymer obtained according to step b) are dissolved in the medium.
In an embodiment of the invention the polymerization according to step b) and the provision of a solution according to step a) is effected using a solution polymerization reactor. Suitable reactors are those known to the skilled in the art and include commonly known flow-through polymerization reactors.
Step c) of the process may employ distillation to separate un-reacted residual monomers, i.e. the isoolefin monomers and the multiolefin monomers from the medium. This mitigates the formation of undesirable halogenation byproducts from the unreacted monomers. The process is conducted at a moderate or relatively high ratio of monomers to the common aliphatic medium. Typically, the isoolefin monomers have a significantly lower viscosity than the common aliphatic medium and therefore, a higher monomer level results in a lower overall viscosity. Overall energy efficiency and raw material utilization of the process is improved by eliminating the need to separate the rubber from a first diluent or solvent used for polymerization, then re-dissolve it in a second solvent for bromination and by recycling bromides resulting from bromination back to a brominating agent. The integrated process according to the invention therefore provides improved energy and raw material efficiency and a reduction in the number of process steps as compared with conventional non-integrated processes for making brominated rubbers, in particular bromobutyl rubbers.
In an embodiment of the invention the bromination according to step d) is performed in a continuous process, for example using a commonly known flow-through halogenation reactor.
BRIEF DESCRIPTION OF THE DRAWING
Having summarized the invention, preferred embodiments thereof will now be exemplarily described with reference to FIG. 1 which shows a process flow diagram for a process according to the present invention that employs purification and optional recycle of un-reacted monomers following separation thereof from the polymer solution.
DETAILED DESCRIPTION
Referring to FIG. 1 , a solution polymerization reactor 40 is provided with a feed of monomers M, comprising isoprene and isobutylene, and a feed of the common aliphatic medium S via an optional heat exchanger 10 , preferably a recuperative heat exchanger, and feed cooler 20 . The monomers may either be pre-mixed with the common aliphatic medium or mixed within the polymerization reactor 40 . A catalyst solution, comprising a carbocationic initiator-activator system of the type used for butyl rubber polymerizations (e.g. a trivalent metal species, such as aluminum, and a small amount of water), is pre-mixed with the common aliphatic medium S in a catalyst preparation unit 30 and also introduced to the reactor 40 . The solution polymerization is then allowed to occur within the polymerization reactor 40 . Solution polymerization reactors 40 of a type suitable for use in the present integrated process, along with process control and operating parameters of such reactors, are described, for example, in EP 0 053 585 A, which is herein incorporated by reference. Conversion is allowed to proceed to the desired extent and then a reaction stopping agent Q, for example water or an alcohol such as methanol, is added and mixed into the reactor discharge stream comprising the common aliphatic medium S, un-reacted monomers M and butyl rubber IIR in mixer 50 . The resulting polymer solution comprising un-reacted monomers M i.e. isoprene and isobutylene, the common aliphatic medium S and butyl rubber IIR is passed through a recuperative heat exchanger 10 where it is warmed by the incoming feeds to the reactor, while at the same time helping to cool these feeds before they enter the final feeds cooler 20 . The warmed polymer solution is then directed to a distillation column 60 for removal of the un-reacted monomers. Once the un-reacted monomers have been separated as recycling stream M R , they exit from the top of the column 60 and the separated polymer solution (S, IIR) exits from the bottom of the column 60 to a solution bromination reactor 70 . Additional common aliphatic medium S and/or water W may be provided to the bromination reactor 70 in order to provide the desired conditions for bromination. It is important to note that the same common aliphatic medium used for polymerization accompanies the butyl rubber through the process to bromination and that there is no need to separate the polymer from the solvent prior to bromination. A feed of a bromination agent B and an oxidizing agent OX (as described hereinafter) is also provided to the bromination reactor 70 . The bromobutyl rubber (BIIR) exits the reactor in solution (S, BIIR) and is then finished using finishing equipment 80 , as is conventionally known. The common aliphatic medium removed during the finishing step is sent as recycling stream S R to solvent recovery 110 prior to introduction to solvent purification section 120 . Additional common aliphatic medium S F may be added before purification 120 or afterwards, if the medium has already been pre-purified. The purified common aliphatic medium is recycled back to the recuperative heat exchanger 10 and final feed cooler 20 for re-use in the process. The un-reacted monomers separated from the polymer solution in the distillation column 60 are sent as recycle stream M R to monomer recovery unit 90 and are then purified in monomer purification section 100 prior to being recycled back to the recuperative heat exchanger 10 and feed cooler 20 . Additional fresh monomers M F may be added either prior to monomer purification 100 or afterwards, if the monomers have been pre-purified. The use of a common aliphatic medium for both polymerization and bromination reduces environmental impact and improves economic performance of the integrated process as compared with conventional approaches.
The description of the process given hereinabove is exemplary and can be applied to all common aliphatic media compositions as well as to all monomer and product compositions mentioned herein.
It is within the scope of the present invention that the composition of the common aliphatic medium may have a slightly varying composition before and after removal of the un-reacted monomers due to different boiling points of its components.
The monomer mixture used to produce the butyl rubber, by solution polymerization is not limited to a specific isoolefin or a specific multiolefin or to specific other co-polymerizable monomers, provided that the individual monomers have boiling points lower than the aliphatic hydrocarbons of the common aliphatic medium which are selected from those aliphatic hydrocarbons having a boiling point in the range of 45° C. to 80° C. at a pressure of 1013 hPa. It is clear that the boiling point of the monomers may be higher than 45° C. at a pressure of 1013 hPa, if the aliphatic hydrocarbons of the common aliphatic medium are selected in such a way that their boiling point is higher than that of the highest boiling component of the monomer mixture but still below 80° C. at a pressure of 1013 hPa.
Preferably, the individual monomers have boiling points lower than 45° C. at 1013 h Pa, preferably lower than 40° C. at 1013 hPa.
Preferred isoolefins are iso-butene, 2-methyl-1-butene, 3-methyl-1-butene, 2-methyl-2-butene or mixtures thereof. The most preferred isoolefin is isobutene.
Preferred multiolefins are isoprene, butadiene or mixtures thereof. The most preferred multiolefin is isoprene.
In one embodiment, the monomer mixture may comprise in the range of from 80.0% to 99.9% by weight, preferably in the range of from 92.0% to 99.5% by weight of at least one, preferably one isoolefin monomer and in the range of from 0.1% to 20.0% by weight, preferably 0.5% to 8.0% by weight of at least one, preferably one multiolefin monomer. More preferably, the monomer mixture comprises in the range of from 95.0% to 98.5% by weight of at least one, preferably one isoolefin monomer and in the range of from 1.5% to 5.0% by weight of at least one, preferably one multiolefin monomer. Most preferably, the monomer mixture comprises in the range of from 97.0% to 98.5% by weight of at least one, preferably one isoolefin monomer and in the range of from 1.5% to 3.0% by weight of at least one, preferably one multiolefin monomer.
In a preferred embodiment of the invention the ranges given above apply to monomer mixtures wherein the isoolefin is isobutene and the multiolefin is isoprene.
In one embodiment, the multiolefin content of butyl rubbers produced according to the invention is for example in the range of 0.1 mol % to 20.0 mol %, preferably in the range of 0.5 mol % to 8.0 mol %, more preferably in the range of 1.0 mol % to 5.0 mol %, yet more preferably in the range of 1.5 mol % to 5 mol % and even more preferably in the range of 1.8 mol % to 2.2 mol %.
One of the ways in which the aforementioned viscosity problems have been overcome is by selecting a high ratio of monomers to solvent in the polymerization step. Although mass ratios of up to 60:40 monomers to aliphatic hydrocarbon solvent have been used in the prior art, in one aspect the present invention utilizes higher ratios, for example from 61:39 to 80:20, preferably from 65:35 to 70:30. The presence of higher monomer levels, which are predominantly C4 compounds and have lower viscosity than the common aliphatic medium, reduces the solution viscosity to tolerable limits and also permits a higher solids level to be achieved during polymerization. Use of higher monomer levels also allows an acceptable molecular weight to be reached at a higher temperature than when lower levels of monomer are employed. The use of higher temperature in turn reduces solution viscosity and permits greater polymer solids level in the solution.
Another one of the ways in which the aforementioned viscosity problems have been overcome is by selecting the common aliphatic medium as a solvent. A solvent having a higher content or consisting of compounds having a boiling point of less than 45° C. or less at 1013 hPa would have a boiling point such close to the monomers that their separation from the solution would also result in significant solvent removal.
The use of a solvent having a higher content or consisting of compounds having a boiling point of more than 80° C. at 1013 hPa would cause difficulties in the separation from the rubber after bromination. The solution viscosity provided by use of such solvents is also significantly higher than with the common aliphatic medium, making the solution more difficult to handle and impeding heat transfer in the reactor, even when provided with the high monomer to solvent ratios described above.
In a preferred embodiment of the invention the common aliphatic medium comprises at least 80 wt.-% of one or more aliphatic hydrocarbons having a boiling point in the range of 45° C. to 80° C. at a pressure of 1013 hPa, preferably at least 90 wt.-%, even more preferably at least 95 wt.-% and yet even more preferably at least 97 wt.-%. Aliphatic hydrocarbons having a boiling point in the range of 45° C. to 80° C. at a pressure of 1013 hPa include cyclopentane, 2,2-dimethylbutane, 2,3-dimethylbutane, 2-methylpentane, 3-methylpentane, n-hexane, methylcyclopentane and 2,2-dimethylpentane.
The common aliphatic medium may, for example further comprise other compounds which are at least substantially inert under polymerization conditions such as other aliphatic hydrocarbons like for example heptanes and octanes having a boiling point of more than 80° C. at a pressure of 1013 hPa, propanes, butanes, pentanes, cyclohexane as well as halohydrocarbons such as methylchloride and other chlorinated aliphatic hydrocarbons which are at least substantially inert under reaction conditions as well as hydrofluorocarbons whereby hydrofluorocarbons are for example those represented by the formula: C x H y F z wherein x is an integer from 1 to 20, alternatively from 1 to preferably from 1 to 3, wherein y and z are integers and at least one.
In another preferred embodiment of the invention the common aliphatic medium is substantially free of halohydrocarbons.
In another embodiment of the invention the common aliphatic medium has a content of cyclic aliphatic hydrocarbons of less than 25 wt.-%, preferably less than 20 wt.-%.
In another embodiment of the invention the common aliphatic medium has a content of cyclohexane (boiling point: 80.9° C. at 1013 hPa) of less than 5 wt.-%, preferably less than 2.5 wt.-%.
As used hereinbefore the term “substantially free of halohydrocarbons” means a content of halohydrocarbons within the common aliphatic medium of less than 2 wt.-%, preferably less than 1 wt.-%, more preferably less than 0.1 wt.-% and even more preferably absence of halohydrocarbons.
The preferred ratio of monomers to a hydrocarbon solvent is not calculable in advance, but may be easily determined by very few routine experiments. Although increasing the amount of monomers should reduce solution viscosity, making accurate theoretical predictions of the extent of that reduction is not feasible due in part to the complex effect on viscosity of the interaction of various components of the solution at the concentrations and temperatures employed in the process.
In one embodiment, the process temperature of step b) is in the range of −100° C. to −40° C., preferably in the range of −95° C. to −65° C., more preferably in the range of −85° C. to −75° C., yet more preferably in the range of −80° C. to −75° C.
Although higher temperatures are desirable in that energy usage for refrigeration and pumping (due to lower viscosity at higher temperature) are reduced, this generally leads to lower molecular weight polymers that are not as commercially desirable. However, due to the use of high monomer to solvent ratios in the present invention, a reduced but still acceptable molecular weight can be obtained with higher temperatures.
Therefore, in an alternative embodiment, temperatures in the range of −50° C. to lower than −75° C., preferably −55° C. to −72° C., more preferably −59° C. to −70° C., yet more preferably −61° C. to −69° C., are used while still obtaining the desired molecular weight of butyl rubber.
The weight average molecular weight of butyl rubber polymers produced using the processes according to the invention, as measured prior to bromination, typically is in the range of 200 to 1000 kg/mol, preferably 200 to 700 kg/mol, more preferably 325 to 650 kg/mol, even more preferably 350 to 600 kg/mol, yet more preferably 375 to 550 kg/mol, even more preferably 400 to 500 kg/mol. If not mentioned otherwise, molecular weights are obtained using gel permeation chromatography in tetrahydrofuran (THF) solution using polystyrene molecular weight standards.
The viscosity of the solution at the discharge of reactor 40 is typically and preferably less than 2000 cP, preferably less than 1500 cP, more preferably less than 1000 cP. A most preferred range of viscosity is from 500 to 1000 cP. If not mentioned otherwise, viscosities are measured in a rotational rheometer of cone-plate type (Haake). All given viscosities refer to the extrapolated zero shear viscosity.
The solids content of the solution obtained following polymerization is preferably in the range of from 3 to 25%, more preferably 10 to 20%, even more preferably from 12 to 18%, yet more preferably from 14 to 18%, even more preferably from 14.5 to 18%, still more preferably 15 to 18%, most preferably 16 to 18% by weight. As described previously, higher solids contents are preferred, but entail increased solution viscosity. The higher monomer to solvent ratios used in the present process allow higher solids contents to be achieved than in the past and advantageously also permit use of a common aliphatic medium for both polymerization and bromination.
As used herein the term “solids content” refers to weight percent of the polymer obtained according to step b) i.e. in polymerization and present in the rubber solution.
In step c), un-reacted residual monomers are removed from the solution following polymerization preferably using a distillation process. Distillation processes to separate liquids of different boiling points are well known in the art and are described in, for example, the Encyclopedia of Chemical Technology , Kirk Othmer, 4th Edition, pp. 8−311, which is incorporated herein by reference.
The degree of separation is largely dependent upon the number of trays used in the column. An acceptable and preferred level of residual monomers in the solution following separation is less than 20 parts per million by weight. About 40 trays have been found sufficient to achieve this degree of separation. Separation of the common aliphatic medium from the monomers is not as critical and contents of for example up to 10 wt.-% of components of the common aliphatic medium are acceptable in the overhead stream from the distillation process. In a preferred embodiment the contents of components of the common aliphatic medium in the overhead stream from the distillation process are less than 5 wt.-%, more preferably less than 1 wt.-%.
With reference to FIG. 1 , the process of the present invention preferably includes purification of the un-reacted monomers separated from the polymerization solution using the distillation column 60 . A purification unit 100 may be provided for this purpose; alternatively, purification can take place offsite in a separate purification unit. The purified monomers are normally recycled back into the process and mixed with fresh monomers; however, they may alternatively be utilized in a different process or sold separately. Preferred embodiments of the process include these optional purification and recycling steps in order to achieve advantageous overall process economics.
Purification of monomers may be carried out by passing through adsorbent columns containing suitable molecular sieves or alumina based adsorbent materials. In order to minimize interference with the polymerization reaction, the total concentration of water and substances such as alcohols and other organic oxygenates that act as poisons to the reaction are preferably reduced to less than around 10 parts per million on a weight basis. The proportion of monomers that are available for recycle depends on the degree of conversion obtained during the polymerization process. For example, taking a ratio of monomer to common aliphatic medium of 66:34, if the solids level in the rubber solution produced is 10%, then 85% of the monomers are available to be returned in the recycle stream. If the solids level is increased to 18%, then 73% of the monomers are available for recycle.
Following removal of the un-reacted residual monomers, the butyl polymer is brominated In step d). The bromobutyl rubber is produced using solution phase techniques. The separated rubber solution comprising the rubber and the common aliphatic medium, hereinafter also referred to as “cement” is treated with a brominating agent, which is at least partially regenerated by an oxidizing agent.
Supplemental solvent, for example comprising fresh common aliphatic medium, and/or water may be added to the separated rubber solution in order to form a cement having the desired properties for bromination.
Bromination in the common aliphatic medium used during the polymerization step advantageously saves energy as compared with the conventional slurry process by eliminating the need for separating the polymer from the polymerization medium, then re-dissolving it in a different medium for bromination.
Preferably, the amount of brominating agent is in the range of from 0.1 to 20%, preferably from 0.1 to 8%, more preferably from 0.5% to 4%, even more preferably from 0.8% to 3%, yet even more preferably from 1.2 to 2.5%, even still more preferably from about 1.5% to about 2.5% and most preferably from 1.5 to 2.5% by weight of the rubber.
In another embodiment the quantity of brominating agent is 0.2 to 1.2 times the molar quantity of double bonds contained in the rubber, preferably the butyl rubber, preferably 0.3 to 0.8, more preferably 0.4 to 0.6 times the molar quantity.
The bromination agent may comprise elemental bromine (Br 2 ), interhalogens such as bromine chloride (BrCl) and/or organo-halide precursors thereto, for example dibromo-dimethyl hydantoin, N-bromosuccinimide, or the like. The most preferred brominating agent is molecular bromine (Br 2 ).
Where the reaction is conducted with the oxidizing agent present at the onset of the bromination reaction, hydrogen bromide may be used as the bromine source. The preferred bromine source is molecular bromine (Br 2 ).
The oxidizing agents which have been found suitable for the purposes of the present invention are water soluble materials which contain oxygen. Preferred oxidizing agents are selected from the group consisting peroxides and peroxide forming substances as exemplified by the following substances: hydrogen peroxide, sodium chlorate, sodium bromate, sodium hypochlorite or bromite, oxygen, oxides of nitrogen, ozone, urea peroxidate, acids such as pertitanic perzirconic, perchromic, permolybdic, pertungstic, perboric, perphosphoric, perpyrophosphoric, persulfates, perchloric, perchlorate and periodic acids and mixtures of the aforementioned compounds.
Such oxidizing agents may either be used in combination with surfactants or not. In a preferred embodiment no surfactants are added.
Suitable surfactants are for example C 6 -C 24 -alkyl- or C 6 -C 14 -aryl-sulfonic acid salts, fatty alcohols and ethoxylated fatty alcohols and the like materials.
Preferred oxidizing agents are hydrogen peroxide and hydrogen peroxide-forming compounds, such as per-acids and sodium peroxide, whereby hydrogen peroxide is even more preferred.
For safety reasons, hydrogen peroxide is preferably applied in form of its aqueous solutions, in particular its aqueous solutions comprising 25 to 50 wt.-%, preferably 28 to 35 wt.-%, more preferably around 30 wt.-% of hydrogen peroxide.
It was found that the lower the water content in the cement is, the better the bromine utilization and oxidation performance with hydrogen peroxide is.
The weight ratio of hydrogen peroxide to water within the reaction mixture is therefore preferably below 1:100, even more preferably below 1:50, and yet more preferably below 1:10. In one embodiment of the invention, the total amount of water present in the reaction will be provided by the addition of the hydrogen peroxide solution.
The amount of oxidizing agent used in accordance with the invention depends on the amount and kind of brominating agent used. For example from 0.2 to about 5 mol of oxidizing agent per mol of brominating agent may be used, preferably from 0.5 to 3 mol and more preferably from 0.8 to 1.2 mol.
The oxidizing agent may be introduced into the reaction zone at the onset of the bromination reaction, it may be added prior to, concurrently with or subsequent to the addition of the brominating agent.
In a preferred embodiment the oxidizing agent is added prior to the brominating agent to allow its dispersal throughout the reaction medium the oxidizing agent is added concurrently or before the brominating agent.
In another embodiment the oxidizing agent is not added to the reaction mixture until after at least about 50% of the brominating agent has been consumed in the bromination reaction.
The bromination process may be operated at a temperature of from 0° C. to 90° C., preferably from 20° C. to 80° C. and the reaction time may for example be from 1 minute to 1 hour, preferably from 1 to 30 minutes. The pressure in the bromination reactor may be from 0.8 to 10 bar.
The amount of bromination during this procedure may be controlled so that the final polymer has the preferred amounts of bromine described hereinabove. The specific mode of attaching the halogen to the polymer is not particularly restricted and those of skill in the art will recognize that modes other than those described above may be used while achieving the benefits of the invention. For additional details and alternative embodiments of solution phase bromination processes, see, for example, Ullmann's Encyclopedia of Industrial Chemistry (Fifth, Completely Revised Edition, Volume A231 Editors Elvers, et al.) and/or “Rubber Technology” (Third Edition) by Maurice Morton, Chapter 10 (Van Nostrand Reinhold Company© 1987), particularly pp. 297−300, which are incorporated herein by reference.
After completion of the bromination reaction, the polymer may be recovered by conventional methods, e.g., neutralization with dilute caustic, water washing and removal of solvent such as by steam stripping or precipitation using a lower alcohol such as isopropanol, followed by drying. Processing aids and antioxidants may be mixed with the brominated polymer product prior to or subsequent to stripping the solvent.
The brominated rubber may cured in a further step. The curing of brominated rubbers is well known.
Suitable curing systems for use with the present product are those already known in the art for use with brominated rubbers, in particular bromobutyl rubbers and generally include conventional curing systems such as sulphur, resin and peroxide curing systems.
The brominated rubbers and cured brominated rubbers obtainable using the process according to the invention may be used as a part of a tire including, but not limited to an inner liner, tread, sidewall, an adhesive, as part of a thermoplastic elastomer, footwear, storage membranes, protective clothing, pharmaceutical stoppers, linings, and barrier coatings.
EXAMPLES
Example 1
Polymerization and Distillation
Key elements of the process described in FIG. 1 have been operated at pilot scale with reactors of 2 liter total capacity running in a continuous mode. Feeds to the reactors were 3.87 kg/h of isobutene, 0.09 kg/h of isoprene and 2.0 kg/h of hexane giving a monomer/hexane mass ratio of 66:34. The reaction temperature used was −65° C. and a solution having a solids content of 16 wt % was produced. This material had a weight average molecular weight of about 440 kg/mol and an isoprene content of about 1.7 mol-%. The solution from the reactors was fed to a distillation column with 40 trays and separation of the monomers from the rubber solution was performed. The solution was preheated to 42° C. and a re-boiler was used at the bottom of the column to maintain a bottom temperature of 113° C. A reflux condenser was used to return part of the overhead stream to the top of the column maintaining a temperature there of 36° C. The separation achieved in the column left less than 10 ppm of residual isoprene monomer in the separated rubber solution and 1.2% of hexane in the overhead monomer stream. The separated monomers were purified, then re-introduced to the solution polymerization reactor. The separated rubber solution in the hexane solvent was such that bromination could be accomplished by conventional means with addition of supplemental hexane solvent.
Example 2
Halogenation
The separated rubber solution of Example 2 was halogenated using pilot scale bromination equipment. Supplemental solvent in an amount of 10% was added to the separated rubber solution in order to lower the viscosity. To simulate varying plant conditions, supplemental water (if necessary) was added to the solution and allowed to disperse throughout the reaction medium. 30 wt.-% hydrogen peroxide in water (at a molar ratio of 1:1 with bromine to be added) was introduced into this solution and the resulting mixture was agitated at 50° C. for up to 2 minutes prior to the addition of bromine. The amount of bromine added was 24 kg per ton of base rubber (=65% of standard, non-recovery bromination amount). After a reaction period of up to 30 minutes, caustic solution was added to the reaction mixture to neutralize any residual hydrogen bromide, bromine and hydrogen peroxide. The neutralized cement was rinsed with water in a 1:1 mass ratio. Antioxidants (irganox), stabilizers (paraplex) and calcium stearate were dispersed in the cement before steam injection was used to remove residual solvent. The resulting polymer was dried using a hot mill until less than 0.1% mass loss was achieved, and analyzed using proton NMR to determine the microstructure. The NMR results are tabulated below, sorted for varying water concentrations. Values are given in mol %.
%
Water
%
%
trans endo
Total
content
Chemicals
CH 2 —Br
exo-CH 2 —Br
Br
Functional
Experiment
[wt.-%]
Added
(+/−0.01)
(+/−0.02)
(+/−0.02)
Bromine
2a
10.0
65% Br 2 ,
0.02
0.51
0.04
0.57
1.0 mol equiv
H 2 O 2
2b
5.0
65% Br 2 ,
0.03
0.69
0.03
0.75
1.0 mol equiv
H 2 O 2
2c
2.5
65% Br 2 ,
0.04
0.74
0.07
0.85
1.0 mol equiv
H 2 O 2
2d
1.0
65% Br 2 ,
0.06
0.79
0.07
0.92
1.0 mol equiv
H 2 O 2
2e
10.0
100% Br 2 ,
0.07
0.8
0.07
0.94
(for comparison)
no H 2 O 2
Example 3
Polymerization with Recycled Monomers and Recycled Common Aliphatic Medium
The process of Example 2 is operated with a purified overhead stream augmented with the addition of recycled common aliphatic medium obtained from the drying and finishing of brominated butyl rubber. The reactor is then operated and a rubber solution is produced that is comparable to the rubber solution described in Example 2.
Example 4
Polymerization with Recycled Monomers and Recycled Solvent
The process of Example 3 is operated using commercially available technical hexane as the common aliphatic medium. The technical hexane was consisting of
2.0 wt.-% butanes and pentanes having a boiling point below 45° C. at a pressure of 1013 hPa, 97.5 wt.-% pentanes and hexanes having a boiling point in the range of 45° C. to 80° C. at a pressure of 1013 hPa, 0.5 wt.-% hexanes, heptanes and octanes having a boiling point above 80° C. at a pressure of 1013 hPa,
The organometallic catalyst, ethylaluminumsesquichloride, was dissolved in the technical hexane and activated by traces of water.
Key elements of the process described in FIG. 1 were operated at pilot scale with reactors of 2 liter total capacity running in a continuous mode. Feeds to the reactors were fresh monomers (0.874 kg/h of isobutene and 0.0204 kg/h of isoprene), 3.160 kg/h of recycled monomer from the recovery and 1.9 kg/h of technical hexane giving a monomer/hexane mass ratio of 68:32. During this run the monomer/common aliphatic medium mass ratio was changed from 50:50 to 74:26. The reaction temperature used was about −65° C. and a solution with 15 wt % of polymer was produced thereby. This material had a weight average molecular weight of about 475 kg/mol and an isoprene content of about 1.75 mol %. The solution from the reactors was fed to a distillation column with 40 trays and separation of the monomers from the rubber solution was effected. The solution was preheated to 42° C. and a re-boiler was used at the bottom of the column to maintain a bottom temperature of 113° C. A reflux condenser was used to return part of the overhead stream to the top of the column maintaining a temperature there of 36° C. The separation achieved in the column left less than 10 ppm of residual isoprene monomer in the separated rubber solution and 0.35% of hexane in the overhead monomer stream. The separated monomers were purified and then re-introduced to the solution polymerization reactor.
The separated rubber solution was halogenated using a pilot scale bromination equipment. 10% supplemental technical hexane was added to the separated rubber solution and the bromination effected by using elemental bromine. Thereby, a brominated butyl polymer containing 1.8% bromine was produced. The bromobutyl rubber solution was then finished using conventional drying and finishing techniques.
In a different experiment, the bromination solution was prepared as above, but including hydrogen peroxide solution. Elemental bromine (in a molar ratio of 1:1 with hydrogen peroxide) was used in amounts of 65% of the typical rate to create a comparable brominated butyl polymer containing 1.8% bromine. Conventional techniques were used to finish the product.
The foregoing describes only certain preferred embodiments and other features and aspects of the invention will be evident to persons skilled in the art. Variants or equivalents of described elements that function in the same way may be substituted without affecting the way in which the invention works. | The invention relates to an energy efficient, environmentally favorable process for the preparation of brominated rubbers, in particular bromobutyl rubber, that uses a common medium for both solution polymerization and subsequent bromination of the rubber and which further exhibits an enhanced bromine usage due to the use of a oxidizing agent. More particularly, the invention relates to a process that employs a common aliphatic medium for both solution polymerization and bromination of rubber in the presence of a brominating agent and an oxidizing agent with intermediate removal of un-reacted monomers. | 2 |
This application is a continuation of copending application application Ser. No. 08/495,476 filed on Sep. 11, 1995, now U.S. Pat. No. 5,698,149, and International Application PCT/CA93/00506 filed on Nov. 24, 1993 and which designated the U.S.
FIELD OF INVENTION
This invention relates to dies and particularly split dies for producing compacted parts out of powder material having an undercut, and more specifically relates to a device to compact parts out of powder material which includes a pair of dies linearly moveable relative to one another and then phased, and an associated linearly displaceable pair of punches for producing parts which are phased or have an undercut.
BACKGROUND OF THE INVENTION
Devices to compact parts out of powder material for sintering are well known to those persons skilled in the art. In some cases, the compacted part has an undercut which prevents removal of the part or blank from the dies by linear or axial displacement.
Tool sets with split dies are known in powder material compaction to press parts into shapes that have an undercut in the compacting direction.
For example, U.S. Pat. No. 3,773,446 teaches a device for moulding parts to be sintered by compressing powdered material held between a fixed die and moveable die. A pair of punches extending through the dies compresses the powder material. A pressure plate operated by the punch extending through the moveable die engages the moveable die and is also locked to the fixed die during the compression to produce a part having an undercut.
U.S. Pat. No. 3,752,622 teaches a device for moulding blanks with undercut parts to be sintered by compaction of powder material.
The prior art teaches that both parts of the die are tied together while a feed box moves across the top of the dies for filling the cavity with powdered material. After compaction the upper part of the die moves away together with the top punch to eject the part.
One of the disadvantages of the known systems as referred to above relates to the fact that the upper part of the die has to be tied mechanically to the lower part of the die and the upper punch in an alternating mode, thus making a complicated tool rig necessary.
Moreover, gearsets and camsets, for example, are characterized by two levels of the same shape but phased to each other to comprise an undercut in the compacting direction. Such parts may be manufactured in known methods as referred to above with the disadvantages noted therein.
Another disadvantage of the prior art is that the undercut can only be indirectly filled thereby creating a section of lower density in the compacted part.
It is therefore an object of this invention to provide a device that is simpler to construct and more efficient to operate than heretofore known by the prior art.
It is another object of this invention to provide a tool system with a split die where both parts of the die remain tied to one part of the rig during the entire cycle.
It is a further object of this invention to provide a device and method to produce compact phased parts such as gears, cams and the like with less complicated tooling and more efficient fill of the undercut than presently available.
In a first aspect of the invention there is provided a tool set for a powder molding machine having a pair of die sets each having a die and a punch moveable relative thereto to define respective chambers, the die sets co-operable to place the chambers in communication and thereby to define a mold cavity, the punches being movable relative to one another in a direction parallel to a common axis to reduce the volume of the mold cavity and to compress powder therein, the dies being movable relative to one another in a plane normal to the common axis, independently of movement along the common axis, to displace the chambers relative to one another and to define a phased component in the mold cavity, and the dies being separable in the direction of the common axis to permit a molded component to be removed therefrom.
In one aspect of the invention the dies are movable in linear translation, one relative to the other, in the plane normal to said common axis. In another aspect of the invention the dies are movable in rotation, one relative to the other, in said plane normal to the common axis.
In another aspect of the invention, the tool set is additionally movable to filling, transfer, lateral displacement and withdrawal positions and each said punch is at least partially engaged with each of said dies of said respective die sets in each of said filling, transfer, lateral displacement and withdrawal positions.
In still another aspect of the invention there is provided a tool set for mounting in a powder compacting press, the press having an axis of reciprocation, the tool set comprising a first die and punch set for mounting with the press, including a first die and a first punch movable within the first die to form a first chamber for receiving a charge of powder; a second die and punch set for mounting with the press, the second die and punch set co-operable with the first die and punch set and including a second die and a second punch movable within the second die for forming a second chamber therewithin; the second die movable parallel to the axis relative to the first die to meet the first die at an interface; and with the first and second dies in contact at the interface and with the first and second chambers in communication to define a closed mold cavity for containing the charge of powder, the second die being movable relative to the first die to a transversely displaced position.
Another aspect of the invention encompasses a press assembly for producing compacted powder metal parts, that press assembly comprising a powder press having an axis of reciprocation and a tool set for mounting in that press, that tool set including a first die set and a second die set, the first die set having a first die and a first punch movable in sliding engagement with, and relative to, the first die for forming a first chamber, the second die set having a second die and a second punch movable in sliding engagement with, and relative to, the second die for forming a second chamber, the die sets co-operable to place the chambers in communication and thereby to define a mold cavity, the punches being movable relative to one another in a direction parallel to the axis to reduce the volume of the mold cavity and to compress powder therein, the dies being movable relative to one another in a plane normal to the axis independently of movement along the axis to displace the chambers relative to one another and to define a phased component in the mold cavity, and the dies being separable in the direction of the common axis to permit a molded component to be removed therefrom.
One aspect of the invention is a method for making compacted powder parts with a tool set for mounting in a press having an axis of reciprocation, the tool set including a first die and punch set mountable in the press and a co-operating second die and punch set mountable in the press, the first die and punch set including a first die and a first punch movable therewithin to form a first chamber, the second die and punch set including a second die and a second punch movable therewithin to form a second chamber, that method comprising the sequential steps of a) establishing the tool set in a position in which the first chamber and the second chamber are in communication to form a closed mold cavity, with a charge of powder captured therein; b) displacing the second die relative to the first die while maintaining the first and second chambers in closed communication; c) compacting the powder to form a compacted powder part; and d) ejecting the compacted powder part from the tool set, in one embodiment of the invention the step of displacing includes linearly translating the second die relative to the first die. In another embodiment of the invention the step of displacing includes rotating the second die relative to the first die about an axis parallel to the axis of reciprocation. In yet another embodiment of this aspect of the invention step (a) includes a(i) filling the first chamber with the charge of powder; and a(ii) transferring a portion of the charge of powder from the first chamber to the second chamber.
DRAWINGS OF THE INVENTION
These and other objects and features of the invention shall now be described in relation to the following drawings.
FIG. 1 is a top view of a rotationally phased part such as a cam of a design suitable for fabrication with the apparatus and method of the present invention.
FIG. 2 is an elevation of the phased part of FIG. 1 in the direction of arrows '2--'2.
FIG. 3 is a top view similar to FIG. 1 of an alternative embodiment of a phased part.
FIG. 4a shows a tool set in a position for receiving a charge of powder.
FIG. 4b shows the tool set of FIG. 4a in a closed, transfer position.
FIG. 4c shows the tool set of FIG. 4a in a phased position.
FIG. 4d shows the tools set of FIG. 4a in a compacted position
FIG. 4e shows the tool set of FIG. 4a in a withdrawal position for ejecting a compact.
FIG. 5 is a schematic view of a second embodiment of tool set employing multiple punches.
FIG. 6 is an elevation of a press in which the tool set of FIGS. 4a through 4e has been mounted.
Like parts are given like numbers throughout the detailed description of the preferred embodiments of the invention which follows.
DESCRIPTION OF THE INVENTION
An undercut part is shown generally in FIGS. 1 and 2 as 20. It has a first, or upper portion 22 and a second, or lower portion 24. Upper portion 22 has a first, or upper profile 26, and lower portion 24 has a lower profile 28. Upper portion 22 and lower portion 24 meet at an interface 30. An overhang 32 of upper portion 22 extends beyond the perimeter of lower portion 24 defined by lower profile 28. Similarly a toe 34 of lower portion 24 extends beyond the perimeter defined by upper profile 26. The lower face of overhang 32 lying along interface 30 defines an undercut 34.
In part 20 illustrated in FIGS. 1 and 2, upper profile 26 and lower profile 28 are identical, differing only in angular orientation. As shown they represent adjoining cams of a cam set, each having a major arc 36 and 38, respectively, and a minor arc, 40 and 42, respectively, joined by tangential surfaces 44. As shown, major arcs 36 and 38 share a common radius of curvature about an axis 46, which, for convenience shall arbitrarily be referred to as a longitudinal, or vertical axis. Overhang 32 corresponds to that portion of upper profile 26 that extends beyond lower profile 28 when upper profile 26 has been displaced relative to lower profile 28 by rotation about, and in a plane perpendicular to, axis 46 through a phase angle α, as indicated in FIG. 2. In such a position upper portion 22 is rotationally phased relative to lower portion 24.
In a part 50 illustrated in FIG. 3, once again there is provided upper portion 22 and lower portion 24 having profiles 26 and 28 respectively, and overhang 54 and a toe 56. In this case profiles 26 and 28 share a common major axis 58 and have respective minor axes 60 and 62. Axes 58, 60, and 62 are perpendicular to axis 46. Axes 60, and 62 are offset laterally, that is to say, transversely to axis 46, from each other by linear translation through a translational phase displacement indicated as δ. In the position shown in FIG. 3, upper portion 22 is translationally phased relative to lower portion 24.
Although a cam set, in the nature of part 20 or part 50, is illustrated in FIGS. 1, 2 and 3, the invention as described herein can be used to manufacture gear sets or any other part which is phased or has an undercut in the compacting direction, that is, the direction parallel to axis 46. A tool set 70 for making phased parts, such as part 20 or part 50, is shown, in simplified form, in FIGS. 4a through 4e. An axis 68, which is arbitrarily denoted a longitudinal, or vertical axis, is defined to facilitate explanation. Tool set 70 includes an upper die set comprising an upper die 72 and a mating upper punch 74. The punch 74 can slide within die 72 so can move parallel to axis 68. Tool set 70 also includes a lower die set including a lower die 76 and its corresponding mating lower punch 78 which is slidably mounted for movement parallel to axis 68. Tool set 70 may be mounted in a press 80, as shown in FIG. 6, of a type well known to those skilled in the art, which includes a head having an upper ram 82, and a base having lower ram 84 and press table 86 which is fixed relative to the frame of press 80.
As shown in FIG. 6, lower punch 78 is rigidly mounted to press table 86. Lower die 76 is mounted about lower punch 78 and is rigidly mounted to lower ram 84 on supports 88 such that motion of lower ram 84 relative to press table 86 parallel to axis 72 will result in corresponding relative motion of lower die 76 to lower punch 78. Upper punch 74 is rigidly mounted to upper ram 82 such that motion of upper ram 82 relative to press table 86 parallel to axis 72 will result in corresponding relative motion of upper punch 74 to lower punch 78. Upper die 72 is mounted to upper ram 82 through the medium of a drive system 90 which may comprise a pair of hydraulic cylinders 92 mounted to upper ram 82.
Phased rotation may be accomplished by a variety of means. As illustrated in FIG. 6, upper ram 82 is further provided with a cylindrical body 94 having gearing 96. Press 80 is provided with a worm gear 98 for engagement with gearing 96. Phased rotation of upper die 72 and upper punch 74 relative to lower die 76 and lower punch 78 is then achieved by activating worm gear 98 to engage gearing 96, thereby causing cylindrical body 94, and hence upper die 72 and upper punch 74, to rotate about axis 68.
Phased lateral movement may be accomplished by a variety of means such as using an hydraulic cylinder which could be activated to move upper punch 74 and upper die 72 laterally relative to lower die 76. The method of operation of tool set 70 will now be described with the aid of FIGS. 4a through 4e. FIG. 4a shows tool set 70 in an open, filling position for receiving a charge of powder, indicated generally as `A`. Lower die 76 is shown at its highest position relative to lower punch 78, and the space between them, that is to say, the space between lower die wall 98 and lower punch distal end face 100 defines a pocket, or lower chamber, 102 for receiving charge `A`. In this open position upper die 72 and upper punch 74 are withdrawn to their highest position to permit a feed box (not shown) to move over lower chamber 102 and deposit charge `A` therein. In a relative sense, lower punch 78 is moved far enough down within lower die 76 that lower chamber 102 can contain the entire amount of powder to form part 20 or 50, as the case may be.
After the filling of lower chamber 102 upper ram 82 is moved down until upper die 72 meets lower die 76 at an interface 104 defined by the contacting surfaces of upper die 72 and lower die 76, closing lower chamber 102. As shown in FIG. 4b, upper ram 82 continues to travel downward to move upper die 72 and upper punch 74. Simultaneously, lower ram 84 moves lower die 76 downward to transfer some of charge of powder `A` from lower chamber 102 into an upper chamber 106 defined as the space between upper die 72 and upper punch 74, that is to say, within upper die wall 108 and below upper punch distal end face 110. When upper die 72 and lower die 76 are brought together to meet at interface 104 chambers 102 and 106 define between them a closed mold cavity 112. Examination of FIGS. 4a through 4e shows that the size of chambers 102 and 106, and hence cavity 112, is variable according to the relative positions of punches 74 and 78, and dies 72 and 76. More specifically, the combined size of chambers 102 and 106, and hence by definition cavity 112, in FIGS. 4b and 4c is equal to the filling size of lower chamber 102 in FIG. 4a. The downward relative motion of lower die 76 relative to lower punch 78 between the filling position of FIG. 4a and the transfer position of FIG. 4b results in upward motion of a portion of charge of powder `A` relative to, and across, interface 104 to enter upper chamber 106.
The movement of powder metal into upper chamber 106, called transfer, occurs prior to phasing so that the powder metal does not have any obstruction to flow which may result in pre-densification. Although lower punch 74 is stationary in FIGS. 4a through 4e, it could also be moved to transfer the powder material into upper chamber 106.
Thereafter upper punch 74 and upper die 76 are phased relative to lower die 76 as illustrated in FIG. 4c to produce part 20 or 50 having undercut 34. In particular the phasing can occur by rotation of dies 72, and 76 relative to each other or by laterally displacing dies 72 and 74 relative to each other. Rotation is particularly advantageous to produce a phased part such as a cam set in the nature of part 20 as illustrated in FIGS. 1 and 2, upper die 72 being rotated relative lower die 76 by the same number of degrees to correspond to angle α as shown in FIG. 1.
In FIG. 4c the upper die and punch pair, that is upper die 72 and upper punch 74 have been phased relative to the lower die and punch pair, that is lower die 76 and lower punch 78. In other words there is lateral displacement transverse to axis 68 of one die and punch pair. The movement of the powder metal into the upper cavity, called transfer, occurs prior to phasing so that the powder metal does not have any obstruction to flow which may result in pre-densification. As also shown in FIGS. 4b and 4c, phasing occurs with chambers 102 and 106 in closed communication and with dies 72 and 76 in contact at interface 104.
FIG. 3 illustrates another part which is laterally phased.
FIG. 4 illustrates the device 17 which includes the top or upper die 1, at least one top or upper punch 2, a bottom or lower die 3, and at least one bottom or lower punch 4.
The top die 1 has a drive system 6 which may comprise a pair of hydraulic cylinders mounted to the upper ram 32 of a press 30. Accordingly, the top die is moveable relative the upper ram by means of the drive system 6. The top punch 2 is mounted on the upper ram 32 in a manner which shall be more precisely described below while the bottom die 3 is mounted to the lower ram 34 of the press 30.
The upper punch 2 is associated with the upper die 1. In particular, the upper die 1 has a hole 8 for receiving upper punch 2 for slidable relative motion therebetween.
The lower punch 4 is mounted for relative linear slidable movement with the lower die 3. In particular, lower die 3 includes a hole 9 to receive punches 4 for relative slidable movement therebetween.
The upper die 1 and lower die 3 are adapted for linear relative movement between an open position as illustrated in FIG. 4a and a closed position as shown in FIG. 4b. In the open position, a feed box (not shown) moves over the cavity 7. The cavity 7 is defined by the space between the lower die 3 and the lower punch 4 when the lower punch 4 is in its lowest position relative the lower die 3. The lower punch 4 is moved far enough down or in its lowest position that enough powder 12 can be stored for the compaction of the part 13.
After filling of the cavity 7 the upper ram 32 is moved down until the upper die 1 is touching the lower die 3 as shown in FIG. 4b for sealing of the cavity 7. As shown in FIG. 4b, the upper ram continues to travel downward so as to move the upper die and the upper punch. Simultaneously, the lower ram moves the lower die downward so as to transfer the powder 12 from the lower cavity 7 into the upper cavity 14 in the top die 1. In other words we have movement between the upper punch, upper die and lower die relative the lower punch. The movement of the powder metal into the upper cavity occurs prior to phasing so that the powder metal does not have any obstruction to flow which may result in pre-densification. The upper cavity 14 is defined by the upper die 1 and upper punch 2.
Although the lower punch 4 is stationary in FIG. 4, the lower punch 4 could also be moved to transfer the powder material into the upper cavity 14.
Thereafter the upper punch and upper die is phased relative the lower die as illustrated in FIG. 3c so as to produce a part 13 having an undercut 15. In particular the phasing can occur by rotation of the dies 1, and 3 relative each other or by laterally displacing the dies. Rotation is particularly advantageous so as to produce a phased part such as the camset 2 illustrated in FIGS. 1 and 2. Moreover, the upper die would be rotated relative the lower die by the same number of degrees so as to correspond to the angle as shown in FIG. 1.
Phased rotation may be accomplished by a variety of means such as, for example, utilizing a worm gear 60 which could be activated so as to engage gears 62 and thereby cause the cylindrical body 64 to rotate about axis 66. The cylindrical body 64 is mounted to the ram 32 and the upper punch 2 and upper die 1 is mounted to the body 64.
Phased lateral movement may be accomplished by a variety of means such as utilizing an hydraulic cylinder which could be activated to move upper punch 74 and upper die 72 laterally relative to lower die 78, that is, transverse to, or in a plane normal to, vertical axis 68.
The compaction step is then shown in FIG. 4d and is accomplished by moving upper ram 82 and both dies 72 and 76 and upper punch 74 with a suitable speed relationship. After compaction the part indicated generally as B' is ejected by withdrawing upper die 72 upward and lower die 76 downward as shown in the ejection position FIG. 4e in which upper die 72 and lower die 76 have been separated at interface 104 and withdrawn, upper die 72 withdrawn flush with upper punch 74 and lower die 76 withdrawn flush with lower punch 78 to expose part `B`. Compaction occurs after phasing. As shown in FIGS. 4a to 4e, respectively, tool set 70, and hence a press assembly including press 80 of FIG. 6 and tool set 70, is movable to filling, transfer, transverse displacement, compaction and withdrawal positions. Upper die 72 is illustrated mounted in at least partial engagement of upper punch 74, and Lower die 76 is illustrated mounted in at least partial engagement of lower punch 78 throughout FIGS. 4a to 4e.
The embodiment illustrated in FIGS. 4a through 4e shows the compaction of a single level part 20 or 50 with an undercut 34. The invention is not limited thereto but can also be used for multilevel parts with an undercut by introducing necessary additional top and bottom punches. For example, FIG. 5 illustrates a tool set 120 for producing a part having multiple levels by utilizing several punches. Those illustrated in tool set 120 of FIG. 5 include a core rod 122; an inner lower, or hub punch 124, disposed about core rod 122; an intermediate lower, or lower web punch 126, disposed about hub punch 124; and an outer lower, lower flange, or lower crown punch 128, disposed about lower web punch 126 and contained within a lower die 130. Corresponding upper die and punch components are shown as an upper, upper web or upper inner punch 132 having an aperture 134 for admitting core rod 122; an upper outer, upper flange, or upper crown punch 136; and an upper die 138. Upper inner punch 132, upper crown punch 136 and upper die 138 are nested in a manner similar to that described for lower members of tool set 120. Numeral 140 shows the pitch diameter of the tooth form within the punches and respective dies. Rotationally phasing upper die 138 relative to lower die 130 according to he method of the present invention through a phase angle a will result in α part having upper and lower gear profiles having teeth offset by that angle.
In order to conduct all necessary movements during the cycle with suitable precision, speeds and timing, an hydraulic press with closed loop controls is preferably used, although the invention is not limited thereto.
The drawings illustrate the withdrawal principal which means that after compaction the lower die is withdrawn to eject the part. However the invention described herein is also applicable for the counterpressing principle in which case the bottom, or lower, die is stationary relative to the press and all the bottom, or lower punches are mounted to the lower ram (including the drives for achieving relative movements between the bottom punches, if more than one bottom punch), so that after compaction the bottom punches will be moved further through the bottom die by the lower ram in order to eject the part.
Although the preferred embodiment and its the operation and use have been specifically described in relation to the drawings, it should be understood that variations from the preferred embodiment could be achieved by a person skilled in the art without departing from the spirit of the invention as claimed herein. | This invention relates to a device to compact parts with an undercut out of powder metal, including a pair of dies linearly moveable relative to one another and then phased, and an associated linearly displaceable pair of punches to produce said parts with said undercut. | 8 |
BACKGROUND OF THE INVENTION
[0001] The present invention relates both to a method and to apparatus for establishing a conference or multi-party call including members of a wireless local area network, particularly, although not exclusively, a low power radio-frequency network (LPRF).
[0002] The development of wireless local area networks has stemmed from a desire to replace the cabling and line of sight techniques presently required to connect modern digital electronic equipment such as personal computers, printers, facsimile machines and the like. In addition, the network confers the further advantage of enabling users to form relatively small ad hoc networks or piconets which can bridge to existing voice and data networks and, indeed, another piconet to form a multiple piconet structure or scatternet.
[0003] A digital device capable of utilising a wireless local area network will be provided with a module providing additional functionality in the form of a radio unit, a link control unit, link management and the relevant software including that necessary to interface with the functionality of the device. It has been proposed to provide cellular radio telephone with such a module. Once connected to the network a user of the telephone should be able to transfer data such as phone book entries, for example both to and from his telephone to other devices such as a personal computer, a printer or the like attached to the network.
[0004] A traditional use of telephones for group working has been conferencing. Traditionally, a conference call has been established using the Public Switched Telephone Network (PSTN). Such a call to multiple participants requires the establishment, over the PSTN of a number of connections.
[0005] Consequently, a conference call has been much more expensive in terms of both network resources and subscriber charges than a typical point to point call. Furthermore, it can be difficult and time-consuming to set up a conference call particularly if a language barrier exists in dealing with a network operator.
[0006] It is thus an aim of the present invention to attempt to reduce the cost and complexity involved in making a conference call. It is a further aim of the invention to seek to provide a conference call facility on a network having only limited telephony resources.
SUMMARY OF THE INVENTION
[0007] According to a one aspect of the invention there is provided a communications device for performing conferencing, the device being operable in a first radio communications network and a second different radio communications network and comprising a first transceiver for establishing a channel for connection in the first network and a second transceiver for establishing a channel for connection in the second network and a controller for establishing a call in the first network and routing the call through the channel in the second network.
[0008] Preferably, the memory will hold data indicative of whether a particular member of the first network is available to be joined or added to a call. Conveniently, the member of the network will be able to indicate to the first network whether he is available for inclusion in the conference call. Thus, in the event that the user does not wish to be disturbed or is perhaps involved in a separate call, he can indicate as such to the network which will result in the relevant data being held in the memory of the device.
[0009] Again preferably, the user of the device may dismiss or remove a member of the first network from the call. Alternatively, the member of the first network taking part in a call may request or order that he be removed from the call. The former situation might arise where network conditions are such that a reliable connection of acceptable quality of service (QoS) cannot be maintained over the network connection, for example. The latter situation might arise where the member leaves the network perhaps through moving out of range.
[0010] According to another aspect of the present invention, there is provided a method of performing conferencing using a communications device and comprising establishing a channel for connection in a first network, establishing a channel for connection in a second different network, establishing a call in the first network and routing the call through the channel in the second network.
[0011] According to yet another aspect of the present invention, there is provided a radio communications system comprising a base station of a second radio communications network and a plurality of communication devices forming a first wireless communications network, at least one of which devices being operable in the first radio communications network and the second different radio communications network and comprising a first transceiver for establishing a channel for connection in the first network and a second transceiver for establishing a channel for connection to the base station in the second network and a controller for establishing a call in the first network and routing the call through the channel in the second network.
[0012] It will be appreciated in relation to the above described aspects of the invention, that the first radio communications network can be a Low Power Radio Frequency Network (LPRF) whilst the second radio communications network can be a mobile cellular radio network as exemplified by GSM.
[0013] Depending on the requirements of each network, the transceivers may be required to operate simultaneously. Furthermore, although separate transceivers could be employed for each network, they could be substituted for a single transceiver capable of operating in more than one network.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] In order to understand the invention more fully, an embodiment thereof will now be described by way of example and with reference to the accompanying drawings, in which:
[0015] [0015]FIG. 1 is a diagrammatic view of a network engaged in a multi-party or conference call according to a method of the present invention;
[0016] [0016]FIG. 2, is a flowchart illustrating the steps taken in establishing the multi-party call of the method of FIG. 1;
[0017] [0017]FIG. 3, is a schematic view of a communication device for use in the method of FIG. 1.
[0018] In the following description although reference is made to protocols defined under the Bluetooth—Low Power Radio Frequency (LPRF) network specification, this is intended to be merely illustrative and is not intended in any manner to be limiting.
DETAILED DESCRIPTION OF THE INVENTION
[0019] Referring to the Figures, there is shown a collection of devices each equipped with a LPRF module 1 (see FIG. 3). The devices include a number of cellular radio telephones 2 a, 2 b, 2 c, 2 d. As is well known, each radio telephone or mobile station 3 forms part of a public land mobile network (PLMN) 4 which through various gateways 5 may in itself be linked to other networks such as a PSTN 6 .
[0020] Referring to FIG. 3, there is shown a communication device namely a radio telephone 2 a including the well known baseband 10 a, RF 10 b, and processor 10 c components which together permit the telephone to operate within the PLMN. The telephone 2 a further includes the LPRF module 1 that contains a radio unit 7 that provides an air interface that complies with Federal Communications Commission (FCC) rules for the Industrial, Scientific and Medical (ISM) band at power levels up to 0 dBm. The interface operates in a frequency-hopping mode that results in a spread spectrum operation in the range of 2.402 GHz to 2.480 GHz with a 1 MHz separation. The nominal link range is 0.1 m to 10 m extensible to 100 m with an increased transmit power. A full description of the air interface can be found in the reference document Bluetooth specification Version 1.0B at http://www.bluetooth.com.
[0021] The module 1 further contains a baseband section 8 that contains the hardware providing the digital signal processing functions necessary to carry out baseband protocols and low-level link routines. The baseband section 8 supports both synchronous and asynchronous connection types, the first of which is used for voice and the second for data. Further explanation of the baseband section 8 can be found in the abovementioned reference document.
[0022] The module 1 also includes software providing both Link management and a top layer providing a framework for interoperability with existing specifications such as TCP/IP as well as the functionality necessary to provide audio communication and voice calls, for example. Again, further explanation of the link management layer and software framework may be found in the abovementioned reference document.
[0023] Referring to FIG. 1 in particular, the devices 2 are shown forming an ad-hoc piconet (shown bounded by the chain line 9 ) in which a connection-oriented L2CAP channel pre-exists between the devices 2 as defined in the abovementioned reference document. However, in order to undertake a multi-party or conference call a wireless user group (WUG) must be in place. For a device to form part of the WUG, it must be equipped with a LPRF module 1 that is capable of supporting the telephony Control Specification (TCS) set out in the abovementioned reference. Thus, in the present embodiment, the cellular radio telephones 2 a, 2 b, 2 c, 2 d are so equipped whilst devices such as a printer 2 e and a card reader 2 f shown in FIG. 1 are not.
[0024] A conference call is initiated by a user, hereinafter referred to as the master user, of a radio telephone 2 a who is already involved in a call via the PLMN 4 to a third party, it being immaterial who initiated the call. Assuming a call is in progress, the master user firstly selects via a graphical interface shown on a LCD display 11 of the radio telephone 2 a, a conference call set-up icon. Selecting the icon launches the following steps in the formation of a Wireless User Group made up of those devices 2 a, 2 b, 2 c, 2 d within the existing piconet 9 that support the TCS protocol: Firstly, the LPRF module 1 processes the instruction selected by the master user by designating 12 itself as a WUG Master. As WUG Master, the module 1 begins polling 13 the known devices 2 of the piconet 9 to determine which are both capable of and willing to join a conference call. Whether a device is capable of joining a conference call will, of course, depend on whether it supports the TCS protocol. If the polled device does support this protocol 14 , the next step is to determine whether the device has been configured with the facility to join a WUG enabled 15 . Clearly, in some instances it may not be desirable for the device 2 to join a conference call, for example where the device 2 d is engaged in an incompatible activity such as carrying out an independent telephone call over the PLMN 4 . Alternatively, the facility to join a conference call may be manually disabled by a user who perhaps does not wish to be disturbed. In either case, the facility may be most conveniently placed under software control and accessed via a graphical user interface displayed on the device 2 . Once the WUG Master has determined which devices are available to join a conference call, the Master user is provided 16 on the display of his radio telephone 2 a with a list of those devices 2 b, 2 c, from which he may select 17 to join the conference call, subject, of course, to any limitations on the support for concurrent connections within the piconet 9 . Thus, the Master user may selectively add devices 2 to the conference call following which step, a voice connection is established between the selected device 2 and the call taking place between the master user and the third party. The Master user can repeat this step with as many devices 2 as required, up to any limit provided by the LPRF networking protocol with the result that the users of all the selected devices 2 b, 2 c, the Master user's device 2 a are connected to each other and to the third party.
[0025] In addition to adding to additional devices 2 to a conference call, the Master user may also selectively dismiss devices 2 from the conference call via a list of joined devices 2 displayed on his radio telephone 2 a. In addition, a user of a joined device 2 b, 2 c may select an icon on a display of his own device 2 b, 2 c to dismiss his device 2 b, 2 c from the conference call. Furthermore, in the event that the Master user ends his call with the third party this will automatically end the conference call and cause all the joined devices 2 b, 2 c to be dismissed. It should be noted that the step of adding or dismissing a device 2 from a conference call is a dynamic process and in no sense does dismissing a device 2 from a call prevent its re-entry at a later stage at the request of the master user subject of course to the dismissed device 2 disabling the conference call facility by the methods described above.
[0026] It will be appreciated by those skilled in the art that the security of the conference call is dependent on the particular networking protocol under which the LPRF network operates. For example, the Bluetooth security protocols provide the security necessary to prevent eavesdropping on any communication between devices connected to a network. The devices may also be able to support other forms of shared information such as multimedia content in addition to voice. Furthermore, although the above described embodiment describes a group of interfaced cellular radio telephones, it should be understood that the invention is equally applicable to a wireless local network in which not all the devices include means for communicating externally of the network including, but not limited to, such devices as multimedia personal computers, cordless handsets and the like. | A conference call facility is described in which one ( 2 a ) of a group of communication devices ( 2 a, 2 b, 2 c, 2 d ) connected to a low power radio frequency network ( 9 ) is able to set up a call to a party external of the network ( 9 ) and then selectively add further devices ( 2 a, 2 b, 2 c ) to the call under the control of the user of the one device ( 2 a ). The users of the other devices ( 2 b, 2 c ) are able to enable or disable the selection of their device in a conference call. One or more of the communication devices may be a mobile radio telephone equipped with the necessary network interface ( 1 ). | 8 |
FIELD
[0001] The present disclosure relates to fuel control systems and methods for heating catalysts in exhaust systems.
BACKGROUND
[0002] The background description provided herein is for the purpose of generally presenting the context of the disclosure. Work of the presently named inventors, to the extent it is described in this background section, as well as aspects of the description that may not otherwise qualify as prior art at the time of filing, are neither expressly nor impliedly admitted as prior art against the present disclosure.
[0003] An engine combusts an air/fuel mixture to generate drive torque for a vehicle. The air is drawn into the engine through a throttle valve and an intake manifold. The fuel is provided by one or more fuel injectors. The air/fuel mixture is combusted within one or more cylinders of the engine. Combustion of the air/fuel mixture may be initiated by, for example, compression provided by a piston and/or spark provided by a spark plug. Combustion of the air/fuel mixture produces exhaust gas. The exhaust gas is expelled from the cylinders to an exhaust system.
[0004] The exhaust system includes a catalyst, such as a three-way catalyst, that reacts with the exhaust gas to reduce emissions. “Three-way” refers to the three emissions that a catalytic converter reduces, including carbon monoxide (CO), unburned hydrocarbons (HCs) and nitrogen oxide (NO x ). The catalyst, however, may be unable to react when the temperature of the catalyst is less than a light-off temperature. Accordingly, the catalyst's reaction capability may be limited upon engine startup (e.g., key ON) when the catalyst temperature is less than the light-off temperature.
[0005] An engine control module (ECM) controls the torque output of the engine. For example only, the ECM controls the torque output of the engine based on driver inputs and/or other inputs. The ECM also controls various engine parameters to warm the catalyst when the catalyst temperature is less than the light-off temperature. For example only, the ECM may retard the spark timing to provide hydrocarbons in the exhaust gas. Oxidation of hydrocarbons in the exhaust system produces heat, which warms the catalyst.
[0006] The amount of heat produced via hydrocarbon oxidation is limited by the amount of oxygen in the exhaust system. A secondary air pump may be mechanically coupled to a cylinder head to provide air directly to the cylinder head. The air delivered by the secondary air pump increases the amount of oxygen in the exhaust system and, therefore, the secondary air pump increases hydrocarbon oxidation capability. The ECM may control operation of the secondary air pump to control oxidation of hydrocarbons in the exhaust system and warm the catalyst.
SUMMARY
[0007] A control system for an engine having N cylinders in first and second banks includes a catalyst heat module and a fuel control module. N is an integer greater than two. The catalyst heat module selectively operates the engine in a catalyst heat mode to heat a catalyst. The fuel control module, throughout a fuel injection sequence for each of the N cylinders, adjusts a first air/fuel (A/F) ratio for the first bank to a rich value and adjusts a second A/F ratio for the second bank to a lean value.
[0008] A method for an engine having N cylinders in first and second banks includes selectively operating the engine in a catalyst heat mode to heat a catalyst, and throughout a fuel injection sequence for each of the N cylinders, adjusting a first air/fuel (A/F) ratio for the first bank to a rich value and adjusting a second A/F ratio for the second bank to a lean value.
[0009] Further areas of applicability of the present disclosure will become apparent from the detailed description provided hereinafter. It should be understood that the detailed description and specific examples are intended for purposes of illustration only and are not intended to limit the scope of the disclosure.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] The present disclosure will become more fully understood from the detailed description and the accompanying drawings, wherein:
[0011] FIG. 1 is a functional block diagram of an exemplary engine system according to the principles of the present disclosure;
[0012] FIG. 2 is a functional block diagram of an exemplary engine control module according to the principles of the present disclosure; and
[0013] FIG. 3 is a flowchart depicting exemplary steps of a control method according to the principles of the present disclosure.
DETAILED DESCRIPTION
[0014] The following description is merely exemplary in nature and is in no way intended to limit the disclosure, its application, or uses. For purposes of clarity, the same reference numbers will be used in the drawings to identify similar elements. As used herein, the phrase at least one of A, B, and C should be construed to mean a logical (A or B or C), using a non-exclusive logical or. It should be understood that steps within a method may be executed in different order without altering the principles of the present disclosure.
[0015] As used herein, the term module refers to an Application Specific Integrated Circuit (ASIC), an electronic circuit, a processor (shared, dedicated, or group) and memory that execute one or more software or firmware programs, a combinational logic circuit, and/or other suitable components that provide the described functionality.
[0016] A fuel control system and method of the present disclosure may operate an engine in a catalyst heat mode to heat a catalyst. In the catalyst heat mode, an air/fuel (A/F) ratio of one cylinder bank is adjusted to lean while an A/F ratio of another cylinder bank is adjusted to rich. Excess carbon monoxide (CO) from the rich bank reacts with excess oxygen (O 2 ) from the lean bank before entering the catalyst to create an exothermic reaction in the catalyst.
[0017] A fuel control system and method of the present disclosure may initiate the catalyst heat mode during a cold start of the engine. The catalyst heat mode may be terminated when the catalyst temperature is greater than or equal to a light-off temperature. In this manner, an exothermic reaction may be created in the catalyst during a cold start to increase the catalyst temperature to the light-off temperature without using a secondary air pump.
[0018] Referring now to FIG. 1 , an engine system 10 includes an engine 12 that may be a port injection engine or a direct injection engine. The engine 12 may include a plurality of cylinders 13 , such as, for example, 2, 4, 6, 8, 10 and 12 cylinders. An exhaust manifold 14 is connected to the engine 12 and directs exhaust gas from the engine 12 through an exhaust pipe 16 to a three-way catalyst (TWC) 18 that may be electrically-heated.
[0019] The cylinders 13 in the engine 12 may be distributed between a first bank 20 and a second bank 22 . The TWC 18 may include an upstream catalyst 24 and a downstream catalyst 26 . The upstream catalyst 24 includes catalyst materials suitable for reducing NO x . The downstream catalyst 26 includes catalyst materials that stimulate oxidation of HC and CO molecules.
[0020] Oxygen sensors 30 at exits of the exhaust manifold 14 measure oxygen levels in the exhaust gas. An engine coolant temperature (ECT) sensor 32 at the engine 12 measures an engine coolant temperature. A catalyst temperature sensor 34 at the TWC 18 measures a catalyst temperature. An ignition input 36 , such as an ignition key or button, generates a start signal.
[0021] An engine control module (ECM) 40 starts the engine 12 based on the start signal. The ECM 40 receives the oxygen levels, the engine coolant temperature, and the catalyst temperature. The ECM 40 determines air/fuel (A/F) ratios for the first and second banks 20 , 22 based on the oxygen levels. The ECM 40 actuates fuel injectors 42 to inject fuel into the cylinders 13 based on the A/F ratios. Air enters the cylinders 13 through an intake valve 44 . The fuel and air combine to form an air/fuel mixture that combusts within the cylinders 13 . Exhaust gas exits the cylinders 13 through an exhaust valve 48 .
[0022] The ECM 40 operates the engine system 10 in a catalyst heat mode during a cold start of the engine 12 . In the catalyst heat mode, the ECM 40 adjusts the A/F ratio of the first bank 20 to rich and simultaneously adjusts the A/F ratio of the second bank 22 to lean. A rich A/F ratio is greater than a stoichiometric ratio and a lean A/F ratio is less than a stoichiometric ratio.
[0023] Referring now to FIG. 2 , the ECM 40 may include a catalyst heat module 200 and a fuel control module 202 . The catalyst heat module 200 receives the engine coolant temperature from the ECT sensor 32 , the catalyst temperature from the catalyst temperature sensor 34 , and the start signal from the ignition input. The catalyst heat module 200 may generate a catalyst heat signal to operate an engine in a catalyst heat mode, thereby heating a catalyst.
[0024] The catalyst heat module 200 may initiate the catalyst heat mode during a cold start of the engine. The catalyst heat module 200 may determine that the cold start occurs when the engine is started and when the engine coolant temperature is less than an operating temperature. The catalyst heat module 200 may determine that the engine is started when the start signal provides direction to start the engine.
[0025] The catalyst heat module 200 may terminate the catalyst heat mode when the catalyst temperature is greater than or equal to a light-off temperature. The catalyst heat module 200 may terminate the catalyst heat mode when the engine coolant temperature is greater than or equal to the operating temperature. For example only, the operating temperature may be approximately 95° C.
[0026] The fuel control module 202 controls the fuel injectors 42 to adjust A/F ratios of cylinders based on the catalyst heat signal received from the catalyst heat module 200 . The fuel control module 202 adjusts a first air/fuel (A/F) ratio to rich and adjusts a second A/F ratio to lean when the catalyst heat signal provides direction to operate the engine in the catalyst heat mode.
[0027] The first and second A/F ratios may be associated with first and second cylinders, respectively. Alternatively, the first and second A/F ratios may be associated with first and second banks cylinder banks, respectively. The second cylinder bank may be closer to the catalyst than the first cylinder bank.
[0028] Rich and lean A/F ratios may vary based on a fuel injection system type. For port injection systems, a lean A/F ratio may be 11.5 and a rich A/F ratio may be approximately 16. For direct injection systems, a lean A/F ratio may be approximately 13 and a rich A/F ratio may be approximately 16.
[0029] Referring now to FIG. 3 , control monitors an engine control temperature in step 300 . Control determines whether a cold start of an engine has occurred in step 302 . Control may determine that the cold start occurs when the engine is started and the engine coolant temperature is less than an operating temperature.
[0030] Control returns to step 300 when the cold start has not occurred. Control monitors oxygen levels in exhaust gas exiting cylinders in step 304 when the cold start has occurred. Control determines first and second air/fuel (A/F) ratios of the cylinders based on the oxygen levels in step 306 .
[0031] Control adjusts the first A/F ratio to rich and simultaneously adjusts the second A/F ratio to lean in step 308 . This creates an exothermic reaction that heats a catalyst. Control may adjust an amount of fuel injected into first and second cylinders to adjust the first and second A/F ratios, respectively. Alternatively, control may adjust an amount of fuel injected into first and second banks of cylinders to adjust the first and second A/F ratios, respectively.
[0032] Control monitors a catalyst temperature in step 310 . Control determines whether the catalyst temperature is greater than or equal to a light-off temperature in step 312 . Control returns to step 304 when the catalyst temperature is less than the light-off temperature. Control stops adjusting the first A/F ratio to rich and the second A/F ratio to lean in step 314 when the catalyst temperature is greater than or equal to the light-off temperature.
[0033] The broad teachings of the disclosure can be implemented in a variety of forms. Therefore, while this disclosure includes particular examples, the true scope of the disclosure should not be so limited since other modifications will become apparent to the skilled practitioner upon a study of the drawings, the specification, and the following claims. | A control system for an engine having N cylinders in first and second banks includes a catalyst heat module and a fuel control module. N is an integer greater than two. The catalyst heat module selectively operates the engine in a catalyst heat mode to heat a catalyst. The fuel control module, throughout a fuel injection sequence for each of the N cylinders, adjusts a first air/fuel (A/F) ratio for the first bank to a rich value and adjusts a second A/F ratio for the second bank to a lean value. | 8 |
BACKGROUND OF THE INVENTION
1. Field of The Invention
The present invention relates to an exposure method and an exposure apparatus and, more particularly, to an exposure method and an exposure apparatus for forming an image of a pattern of a mask on an uppermost layer of a substrate by aligning a pattern formed on a given layer of the substrate with a pattern on the mask.
2. Description of the Related Art
In a method for forming plural patterns in layers superimposed on a substrate by exposure to light, an upper-most layer of the layers superimposed on the substrate is generally formed with a new pattern by aligning the new pattern with one of the previous patterns already formed in the layers on the substrate.
For comparative purposes, an example of conventional exposure methods will be described with reference to FIG. 5 illustrating such a conventional exposure method, a first step of which comprises a selection of operation steps, an exposure apparatus and an exposure reticle as a preparation step for operations. Then, a substrate is aligned under alignment conditions and subjected to test exposure to light (pilot or pre-processing), followed by a measurement of an alignment residual error of the substrate exposed to light by a given measurement device. As a result of the test exposure, when it is found that the alignment residual error for the substrate is within a given reference value, a main exposure is carried out. On the other hand, if the alignment residual error for the substrate is found to be outside the given reference value, the alignment conditions are changed on the basis of the alignment residual error measured and the substrate is aligned again under the renewed alignment conditions, followed by the implementation of a main exposure step or the re-implementation of a test exposure step.
In the conventional process as described hereinabove, the alignment conditions may change, too, when conditions for exposing the substrate to light changes. In other words, alignment conditions may also change in each case where an operation step is changed, where a different exposure apparatus is used, where a different reticle for allowing the substrate to be exposed to light is employed, where a substrate is changed for a test exposure, where there is used a different device for exposing an alignment layer with a mark formed as a reference of alignment or where a reticle used for exposure of the alignment layer is changed. In order to sustain a high level of accuracy in alignment, the conventional process requires the test exposure to be conducted again, whenever alignment conditions change. This results in a reduction of throughput.
In order to solve problems and disadvantages encountered with such conventional exposure methods, extensive review and studies have been made to develop an exposure method that can improve throughput of an exposure apparatus while sustaining a high level of accuracy in alignment.
SUMMARY OF THE INVENTION
Therefore, the present invention has the object to provide an exposure method that can improve throughput of an exposure apparatus while sustaining a high level of accuracy in alignment.
It is another object of the present invention to provide an exposure apparatus capable of carrying out the exposure method as described hereinabove.
In order to achieve the above object, the present invention provides an exposure method which comprises storing an alignment error between patterns formed in plural layers superimposed on a substrate so as to correspond with conditions relating to exposure to light and alignment for each of the plural layers; reading an alignment error and an alignment condition corresponding thereto from at least one of the plural layers storing the alignment errors corresponding each to an exposure condition set for an uppermost layer superimposed on the substrate; calculating an alignment condition for the uppermost layer on the basis of information read; and aligning at least one pattern on the substrate with the pattern on the mask in accordance with the alignment condition calculated hereinabove. In a preferable aspect of the exposure method according to the present invention, at least a portion of the conditions relating to exposure to light and alignment for every layer is formed on each layer as an identification code.
The present invention further provides an exposure apparatus for exposing an image of a pattern formed on a mask to each of plural exposing layers superimposed upon a substrate, comprising a storage means for storing an alignment error between patterns formed in plural layers superimposed on a substrate so as to correspond to exposure and alignment conditions for each of the plural layers; an operation means for reading an alignment error and an alignment condition corresponding thereto from at least one of the plural layers storing the alignment errors corresponding each to an exposure condition set for an uppermost layer of the layers superimposed on the substrate and for calculating an alignment condition for the uppermost layer on the basis of data read; and an alignment means for aligning at least one pattern on the substrate with the pattern on the mask in accordance with the alignment condition calculated hereinabove.
In a preferred aspect of the exposure apparatus according to the present invention, the alignment means is provided with an alignment mark detection system for photoelectrically detecting a ray of light emitting from an alignment mark formed in at least one pattern on the substrate by illuminating the alignment mark and it is disposed so as to allow the mask to move relative to the substrate or vice versa in accordance with an output from the alignment mark detection system and the alignment condition calculated. The alignment means may also be provided with a means for recording at least a portion of the exposure and alignment conditions for the uppermost layer of the substrate in the uppermost layer thereof, causing a reader means to optically read the recorded conditions and transmitting the read conditions to the operation means.
With the arrangement of the exposure apparatus in the manner as described hereinabove, the present invention can calculate a new alignment condition by making a search for and retrieving the past alignment conditions in an appropriate fashion. Accordingly, even if exposure conditions and the like for a substrate would change, the exposure apparatus according to the present invention does not require any new test exposure and can calculate a new alignment condition, unlike the conventional exposure apparatuses. This can, as a matter of course, make a period of time required for determining the alignment condition remarkably shorter as compared to conventional techniques.
Other objects, features and advantages of the present invention will become apparent in the course of description that follows, with reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic view showing an exposure system according to an example applied to the present invention.
FIG. 2 is a schematic view showing an essential part of the exposure system of FIG. 1.
FIG. 3 is a plane view showing a wafer to be used for the exposure system of FIG. 1.
FIG. 4 is a flowchart showing an exposure method according to an example of the present invention.
FIG. 5 is a flowchart showing a conventional exposure method.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The present invention will be described in more detail by way of examples with reference to the accompanying drawings. This example is directed to an application of an embodiment of the present invention to a semiconductor projection exposure system for projection exposing a pattern formed on a reticle to a wafer.
A description will first be made of an exposure system according to the example with reference to FIG. 1. The exposure system comprises a coater developer unit 10, an exposure unit 12 for exposing a wafer 100 to light, a main control unit 14 for controlling an entire system comprehensively, and a storage 16 connected to the main control unit 14.
The coater developer unit 10 comprises a wafer cassette 18 for storing a plurality of wafers, a coater 20 for coating a surface of the wafer with a photoresist, a developer 22 for developing the wafer 100 after exposure, an inspection unit 24 for measuring an alignment error of the wafer 100 after development, an articulated robot arm 26 for conveying the wafer 100, and a guide rail 28.
The exposure unit 12 comprises an articulated robot arm 34 for delivering and receiving the wafer 100 to and from the coater developer unit 10, a bar-code reader 36 for reading a bar code formed on the wafer 100, a laser processor 38 for forming the bar code provided on the wafer 100, a prealignment unit 42, and exposure units 47, 52, 54 and 56. The prealignment unit 42 has a turntable 44 for rotating the wafer 100 loaded thereon, and a sensor 46 for sensing an orientation flat of the wafer 100. The wafer 100 is carried and delivered to the prealignment unit 42 by the articulated robot arm 34 disposed so as to move on and along a guide 40. The delivery of wafers between the prealignment unit 42 and the exposure unit 12 is conducted by a slider arm 48 disposed so as to slide on and along the guide 50.
As shown in FIG. 1, one of the plural wafers stored in the wafer cassette 18 is taken by the articulated robot arm 26 and the wafer 100 is then conveyed to the coater 20. The wafer 100 is coated at its surface with a photoresist by the coater 20 and then conveyed to a waiting position 30 by the articulated robot arm 26. The wafer 100 is held at its waiting position 30 by the articulated robot arm 34 mounted on the exposure unit 12 and conveyed to the bar-code reader 36 for reading an identification code, such as a bar code, provided in each layer on the wafer 100. The bar-code reader 36 transmits to the main control unit 14 information read which contains conditions of exposure and alignment at the time of the formation of a pattern on each layer.
The robot arm 34 further moves on and along the guide 40 and delivers the wafer 100 to the turntable 44 of the prealignment unit 42. The prealignment unit 42 irradiates a parallel illumination flux of a non-exposing wavelength onto an outer peripheral portion of the wafer 100 by the sensor 46 while rotating the wafer 100 by the turntable 44. The illumination flux which is not blocked by the wafer 100 is photoelectrically detected. The rotation of the turntable 44 is suspended in accordance with output from the sensor 46, and the orientation flat of the wafer 100 is aligned with a given direction. The wafer 100 is then conveyed to a position above a wafer stage 47 by the slider arm 48 and allowed to be attached by vacuo to a wafer holder 52.
On each of the plural layers of the wafer 100 is formed a pattern in a superimposed fashion and an alignment mark provided on at least one pattern formed on the plural layers is detected by an alignment sensor 56. Then, the main control unit 14 drives the wafer stage 47 on the basis of output from the alignment sensor 56 and a given correction amount (an alignment condition) to align a pattern on the wafer 100 with a pattern of the reticle. Thereafter, the main control unit 14 exposes the uppermost layer of the wafer 100, namely, a photoresist layer provided thereon, to an image of the pattern on the reticle through a projection optical system 54. A method for the calculation of the alignment condition for the wafer 100 will be described hereinafter.
After all the shot areas (patterns) of the wafer 100 are exposed so as to allow the pattern images of the reticle to be superimposed thereupon, the wafer 100 is then transferred from the wafer stage 47 by the slider arm 46 and delivered to the robot arm 34. Then, the robot arm 34 conveys the wafer 100 to the laser processor 38 for recording the conditions relating to exposure and alignment at the uppermost layer of the wafer 100. The laser processor 38 irradiates laser beams having a wavelength range capable of photosensitizing the photoresist coated on the uppermost layer onto the wafer 100, thereby writing the exposure and alignment conditions on the uppermost photoresist layer of the wafer 100 in the form of bar codes, numerals or alphabets.
The wafer 100 with various conditions recorded thereon is conveyed to the waiting position 30 by the robot arm 34 and then to the developer 22 by the robot arm 26. The inspection unit 24 detects rays of light emitting from the wafer 100 by illuminating each of some shot areas and the light is detected photoelectrically by an image pick-up element such as a CCD. Further, image signals from the image pick-up element are scanned by plural scanning lines, thereby measuring an alignment error of alignment of the pattern formed in at least one of the layers on the wafer 100 with the pattern (resist pattern) to be formed on the uppermost layer upon exposure by the exposure unit 12. The measurement results are transmitted to the main control unit 14.
FIG. 2 shows the configuration of the exposure section of the exposure unit 12. The light for exposure emitted from an exposing light source 60 illuminates a reticle 62 held with a reticle stage 64. The reticle 62 is formed with a given circuit pattern which in turn is projected onto the wafer 100 with the projection optical system 54. The wafer stage 47 is disposed so as to be step-movable in both x- and y-directions by a stage drive system 68. The alignment sensor 56 photoelectrically detects an alignment mark (not shown) provided in the shot area of the wafer 100 at a position deviated by a given amount from an optical axis of the projection optical system 54. On the wafer stage 47 is fixed a reflecting mirror 70 which in turn reflects a ray of light emitted from an interferometer 72. The light reflected from the reflecting mirror 70 is received by the interferometer 72 and detects the position of the wafer stage 47. To the projection optical system 54 is connected a control unit 74 for controlling imaging characteristics.
FIG. 3 shows a shot sequence of the wafer 100. In a street line of plural shot areas ES1 through ESN of the wafer 100 are provided alignment marks Mxj and Myi in a lattice form to be detected photoelectrically by the alignment sensor 56. In this example, the wafer is aligned by a so-called EGA (enhanced global alignment) system. In other words, sample areas SA1 through SA9 are selected from the plural shot areas ES1 through ESN and alignment marks provided in these sample areas SA1 through SA9 are detected. The coordinates (x, y) of the shot sequence are determined statistically by the least square.
Then, a description will be made of the method for exposing the wafer 100 to light with reference to the flowchart as shown in FIG. 4. The exposure method according to the present invention may be carried out on the basis of data stored in two databases as will be described hereinafter, namely, database 1 and database 2. The storage 16 stores, as the database 1, alignment residual errors measured by the inspection unit 24 after exposure and conditions of exposure and alignment upon exposure.
The contents of the database 1 are as follows:
1. Names of operation steps;
2. Names of exposure apparatuses;
3. Names of reticles;
4. Names of steps for forming alignment layers;
5. Names of exposure apparatuses for exposing the alignment layers;
6. Names of reticles for exposing the alignment layers;
7. Alignment conditions; and
8. Alignment residual errors.
By the term "alignment layer" referred to herein is meant a layer formed on the wafer 100 on which the alignment mark to be used herein is provided.
As the alignment conditions, there may be used correction parameters as will be described hereinafter. The correction parameters include correction parameters for correcting the coordinates of sequences of shot areas of the wafer 100 as follows:
1. Offset (x, y);
2. Scaling (x, y);
3. Orthogonal degree; and
4. Wafer rotation.
The correction parameters within each of the shot areas further include correction parameters as follows:
5. Shot magnification; and
6. Shot rotation.
In each layer superimposed on the wafer was recorded a wafer ID for each of the exposing steps as database 2 which in turn includes the contents as follows:
1. Names of operation steps;
2. Names of exposure apparatuses; and
3. Names of reticles for exposure.
These data may be recorded in a wafer unit or in a lot unit consisting of plural wafers.
In the exposure method according to the example of the present invention, the main control unit 14 selects an operation step, an exposure apparatus and a reticle for exposure, as a preparatory procedure, and then locates a step for forming an alignment layer, prior to the alignment of the wafer 100 (step 1). Then, the main control unit 14 retrieves the contents of the database 1 stored in the storage 16 (step 2). Further, the main control unit 14 gives an instruction to the bar-code reader 36 which in turn reads the wafer ID to be exposed therein from the database 2 (step 3), followed by retrieving the database 2 (step 4). The main control unit 14 now has both the databases 1 and 2 read therein. It can be noted herein that when the name of the operation step corresponds to the name of the step for forming the alignment layer in a one-to-one manner, it is not required to locate the step for forming the alignment layer in the preparation for operations.
The main control unit 14 then sets the following parameters on the basis of the data read therein from the databases 1 and 2 (step 5).
1. Name of the operation step;
2. Name of the exposure apparatus;
3. Name of the reticle for exposure;
4. Name of the step for forming the alignment layer;
5. Name of the exposure apparatus for exposing the alignment layer; and
6. Name of the reticle for exposing the alignment layer.
Thereafter, the main control unit 14 searches for the past alignment conditions and alignment residual errors corresponding to the above six parameters from the database 1 stored in the storage 16 (step 6). In this search process, it is not necessary to search for all the past data as a search condition and it may be one such as n pieces of latest data or data saved in latest n hours (or days or months). From a mean value of the data for which the search has been made and which has been retrieved, the main control unit 14 calculates new alignment conditions (correction parameters) for the wafer 100 to be exposed from the formula as follows (step 7):
New alignment conditions=corresponding past alignment conditions minus corresponding past alignment residual error.
The new alignment conditions may also be calculated from the coordinates system of a vernier measurement instrument as follows:
New alignment conditions=corresponding past alignment conditions plus corresponding past alignment residual error.
Then, the main control unit 14 corrects information on the position of the wafer 100 detected by the alignment sensor 56 and implements the alignment process in accordance with the new alignment conditions as calculated above. More specifically, the wafer stage 47 is driven by the drive unit 68 and the projection magnification of the projection optical system 54 is controlled by the control unit 74 for controlling the imaging characteristics. The wafer 100 is transferred by the drive unit 68 while the position of the wafer stage 47, namely, the position of the wafer 100, is being monitored by the interferometer 72. After the alignment has been completed, the main control unit 14 then exposes an image of the pattern on the reticle 62 to the shot areas ES1 to ESN of the wafer 100 one after another through the projection optical system 54 (step 8).
It is to be noted herein that the main control unit 14 writes the current exposure and alignment conditions on the wafer 100 through the laser processor 38.
In this example as described hereinabove, the main control unit 14 is disposed so as to control one set of the coater developer unit 10 and the exposure unit 12. It can also be noted herein that it may be disposed so as to control plural sets of the coater developers 10 and the exposure units 12. More specifically, the main control unit 14 can be arranged to control a different exposure unit so as to superimpose a new pattern upon the currently exposed layer and to expose the new pattern to the currently exposed layer on the basis of the current exposure and alignment conditions as well as alignment error.
Although the present invention is described hereinabove on the basis of the examples, it should be understood that it is not limited in any respect to the examples as described hereinabove and it is interpreted as encompassing any modifications and variations from the gist of the present invention within the scope and spirit of the present invention.
The present invention can present the advantages that the time required for determining the alignment conditions can be shortened, thereby improving throughput because the past alignment conditions and alignment errors are stored for each layer to be superimposed on a substrate, the past alignment conditions and alignment residual error, corresponding to the exposure conditions for a layer superimposed on the substrate to be newly exposed, are read from the information stored, and new alignment conditions can be determined on the basis of the information read. | Disclosed is an exposure method for exposing an image of a pattern formed on a mask to plural layers superimposed upon a substrate, comprising: the step of storing an alignment error between the plural layers together with at least one of exposure data and alignment data; the step of setting alignment data upon exposing another pattern to the substrate on the basis of at least one of the exposure data and alignment data; and the step of displacing the mask and the substrate relative to each other on the basis of the alignment data set in the previous step. There is further disclosed an exposure apparatus for exposing an image of a pattern formed on a mask to plural layers superimposed upon a substrate, comprising a storage for storing alignment errors between the plural exposure layers together with at least one of exposure data and alignment data; and a control unit connected to the storage for setting alignment data upon exposing another pattern to the substrate on the basis of at least one of the exposure data and alignment data; wherein the control unit controls the mask and the substrate so as to be displaced relative to each other on the basis of the alignment data set. | 6 |
This application is a continuation-in-part of a copending application, Ser. No. 883,270, filed Mar. 3, 1978 now issued as U.S. Pat. No. 4,169,473 dated Oct. 2, 1979.
This invention relates to an anti-snore and anti-tooth-grinding device, and more particularly, to a device for selective insertion within the mouth of a user so as to obstruct the oral flow of air past the lips of the user, and to increase the size of the air passageway through the oro- and naso-pharynx, and which may also be provided with means for immobilizing jaw movement.
BACKGROUND OF THE INVENTION
Snoring is caused by the relaxation of body tissue in the lingual compartment, the tissue including the tongue, the pharyngeal folds, the soft palate, the muscularis uvulae and the palate-pharyngeal arch. During normal waking hours, muscle tone in most individuals unconsciously maintains the above structures in adequate spacial relationships so as not to interfere with the free passage of air therepast. However, with increasing age, and during periods of unconsciousness, some muscle tone is lost, thereby allowing one or more of the tongue, the pharyngeal folds, the soft palate, the uvulae and the posterior pharyngeal wall to vibrate as tidal air flows therepast.
While the act of snoring is socially discomfitting to other persons who hear the snores, and especially annoying to a spouse attempting to sleep, it can also cause harmful complications to the snorer, such as disturbed rest, excessive drying of the oro- and naso-pharyngeal mucous membranes with consequent injury to the throat, middle and inner ear, susceptibility to infection, vertigo and impaired hearing. Of equal importance is the fact that people who snore are not making use of the physiologically beneficial aspects of nasal breathing. The anatomical nasal structures (such as the turbinates, mucous membranes, etc.) provide moistening and cleansing functions during sleep.
Prior patents, such as U.S. Pat. No. 3,132,647, have dealt with the various lingual compartment tissues and their relationship to the snoring phenomenon. Such patients disclose that snoring should and can be reduced, if not altogether prevented, by providing for unobstructed air flow between the tongue and the soft palate. U.S. Pat. No. 3,132,647 seeks to keep the passage open by engaging and depressing the rear portion of the tongue while supporting a portion of the downwardly-hanging soft palate. Oral breathing is permitted, and no attempt is made to prevent vibration of the forward end of the tongue.
Other patented devices have been proposed as "snore-preventing" such as U.S. Pat. Nos. 1,774,446 and 3,434,470, and British Pat. No. 1,248,474. All such prior proposals have been constructed to permit, or at least allow, the partial inhalation of air orally to insure that oral breathing occurred.
While U.S. Pat. No. 2,867,212 recognizes that snoring is caused by vibrations of the soft palate and uvula and could be prevented if oral breathing is prevented, the mouthpiece described in said patent is intended to serve as an aid for practice of nasal breathing by blocking the oral flow of air. No attempt is made in said device to open the naso-pharynx, thus presenting a troublesome situation for users whose muscle tone is such as to partially close the nasal passageway.
British Pat. No. 751,381 includes a device to be held within the mouth of a user, said device having a central open bore provided for continuous passage of air.
It is one object of the present invention to provide an anti-snore device which serves to receive and hold the forward portion of the tongue in a forward position, thereby drawing the remainder of the tongue forwardly and in such a way that no portion of the tongue, or other oral soft tissue, will vibrate during breathing.
It is a further object of the present invention to provide an anti-snore device which not only holds the forward portion of the tongue forwardly but also prevents oral breathing by obstructing the flow of air through the mouth.
It is another object of this invention to provide an anti-snore device which not only prevents oral breathing, but also, opens the internal air passageway for nasal breathing through the naso-pharynx.
A still further object of the present invention is to provide an anti-snore device which prevents oral breathing by obstructing the flow of air through the mouth, holds the tongue forwardly so as to prevent soft tissue vibration, and opens the air passageway for nasal breathing.
And still another object of this invention is to provide a novel combination anti-snore and anti-bruxism device.
These and other objects and advantages of the invention will become clear from the following description of a preferred embodiment of the invention.
BRIEF SUMMARY OF THE INVENTION
The anti-snore and anti-bruxism device of this invention is adapted for insertion into the mouth of a user with means for obstructing the oral flow of air and for holding the tongue forwardly, thereby preventing oral breathing and enlarging the internal naso-pharynx to enhance nasal breathing. In one form, the device includes a molded body portion of a size to cover the user's mouth and lips, and another portion for entry into the mouth to engage at least one of the user's upper or lower teeth or gum arches to hold the device in position and to prevent the passage of air therepast. In a second form, the device eliminates the portion thereof located outside of the user's lips, and the portion located within the user's mouth is shaped somewhat differently and in a manner that facilitates molding. In both forms a tongue-receiving socket with a closed forward end extends rearwardly from and is provided by the body portion, the rear end of the socket being open and sized and shaped to receive a part of the forward end of the user's tongue. When operatively positioned within the mouth, the user creates a negative pressure within the socket by applying gentle suction, thereby effecting a holding by the socket of a portion of the tongue within the socket. The position of the tongue, when so secured, is to be pulled forwardly of its normal resting position behind the lower teeth. The remainder of the body of the tongue, when held forwardly of its normal proximity to the soft palate, the uvula and the posterior pharyngeal wall, provides an increase in size of the nasal air passageway. Because the devices are molded for removal cooperation with the upper and lower dental arches, relative jaw movement is effectively precluded, and nocturnal tooth grinding is prevented.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a vertical, cross-sectional view, along the longitudinal axis, of line 1--1 of FIG. 2, of a first form of the anti-snoring and anti-bruxism device of the present invention, illustrating the device operatively positioned in the mouth of a user;
FIG. 2 is a perspective view of the embodiment of the invention shown in FIG. 1, the embodiment including upper and lower dental-engaging arches in the anti-snoring device, and with a forward portion of the device partially cut away to provide illustration of the invention's features;
FIG. 3 is a perspective view of a second embodiment of an anti-snoring device of the present invention, the embodiment including an upper dental arch-securing trough;
FIG. 4 is a cross-sectional view of a portion of the molded plastic wall of the anti-snoring device illustrating the use of an embedded layer of wire mesh for strength and shape maintenance;
FIG. 5 is a view similar to FIG. 1 but showing an improved form of the device of this invention;
FIG. 6 is a rear elevational view of the improved form of device shown in FIG. 5; and
FIG. 7 is a side perspective view, somewhat from the rear, of the device of FIGS. 5 and 6.
DETAILED DESCRIPTION OF THE INVENTION
Referring now to the drawings, one form of the anti-snoring and anti-tooth-grinding device of this invention is shown generally as 10 in FIGS. 1 and 2. This specific device comprises a means 12 for preventing the flow of air through the mouth and an elongated tongue-receiving socket 14 for opening the nasal breathing passage.
FIG. 1 depicts the usual anatomical structure of the mouth of a user of the device of the present invention. The mouth includes an upper jaw 50, a lower jaw 52, a tongue 54, the soft palate or musculus uvulae 56 handing downwardly approximate the base of the tongue, the posterior pharyngeal wall 57, and the upper and lower dental arches comprising upper and lower gums or upper and lower natural teeth 58 and 60.
Although the drawings depict a device adapted for mounting about the teeth of a user, it should be apparent that the device is readily modifiable for use by people having few if any natural teeth. For such usage, the U-shaped trough is widened so as to fit the upper and/or lower gums of the dental arches.
The body means 12 includes an enlarged and rearwardly curved front plate 16 adapted to be placed over the exterior surface of the lips so as to completely cover the mouth opening. Also formed as part of the body means 12 is an upper U-shaped trough 18 and a lower U-shaped trough 20 molded to closely conform to the configuration of the upper and lower dental arches and adapted to receive either the gums or the natural teeth 58 and 60 of a user. The upper and lower teeth/gum-receiving, U-shaped, troughs 18 and 20 are spaced apart by a central web 22. Both troughs 18 and 20 and the web 22 are generally semicircular in shape to substantially conform to the anatomical shape of the upper and lower dental arches.
The tongue-receiving socket 14 is an elongated element molded integrally with the body means so as to form an oppositely disposed, closed end 26 extending from the rear wall 17 or the curved plate 16 and an open end 24 extending internally of the mouth and sized to accept the tongue of a user therein. As seen in FIG. 2, the socket 14 may be stabilized by diametrically arranged molded portions 27 extending between the exterior of socket 14 and adjacent exterior portions of an arch 18 or web 22.
FIG. 3 represents a simplified embodiment 10' of the anti-snoring and anti-bruxism device of the present invention disclosed in FIGS. 1 and 2, and wherein identical numbers represent substantially identical parts of the FIGS. 1-2 embodiment. A tongue-receiving socket 14' is molded integrally with an upper U-shaped trough 18' and a curved front plate 16'. The socket 14' includes a forward, closed end 26' and an open, rear end 24'. In this form, the device 10' may be inserted into the mouth of a user to engage the upper dental arch with the lower surface 28' of the trough resting upon the top of the lower dental arch. The lower trough surface 28' assists in clamping the device 10' between the upper and lower jaws so that the socket 14' will be positioned to hold the tongue 54 forward of its normal position. The main securing force is furnished by the close conformity between the molded upper trough 18' and the upper gum or teeth 58 forming the upper dental arch.
This embodiment permits some voluntary movement of the lower jaw 52 relative to the upper jaw 50 so as to allow swallowing of accumulated saliva. Further, the rigid constraints of the double trough embodiment are absent, thereby alleviating the anxiety which complete enclosure might cause some people. After experiencing this less restrictive model, the user may wish to acquire the more inclusive double trough device 10 or even proceed to a custom-built model.
Although the device could best be fitted by a dentist trained in the art of fabricating similar oral prostheses for the replacement of natural dental structures, a similar device could be produced in several sizes and shaped for over-the-counter sales at considerably less expense. An exact reproduction is not necessary, given the adaptability of the soft and yielding tongue to accommodate itself to a space provided for it.
The device is preferably molded of any well-known synthetic plastic resin that displays properties that render the plastic more pliable if warmed to a relatively low temperature above body temperature, with solidification occurring as it cools to body temperature. One such resin is ethylene vinyl acetate. Alternatively, the troughs could be lined with a yielding rubber or plastic material so that biting down would provide sufficient gripping power to securedlyhold the device. If desired, an oxidation-resistant wire mesh 28 may be embedded with the plastic resin for enhancing structural strength, rigidity and durability (see FIG. 4).
It should be appreciated that a single troughed design for engaging the lower dental arch is also within the scope of this invention.
OPERATION
In use, the device 10 is placed in hot water or otherwise warmed to a temperature above body temperature wherein the plastic becomes pliable, but which will not burn or otherwise harm the oral tissue which it later is to contact. The device 10 is then positioned in the mouth of the user such that the upper U-shaped trough 18 receives the upper teeth 58 and the lower U-shaped trough 20 receives the lower teeth 60. The user, by closing his jaws, bites into the troughs 18 and 20. Since the device is in its heated, pliable state, the upper and lower teeth 58 and 60 make impressions in the trough surfaces 18 and 20. The device 10 is left in position in the mouth until cooling brings about solidification after which the molded impressions operate to secure the device in operative position as seen in FIG. 1.
By means of insertion of the tongue tip and gentle suction therepast, the forward end of the tongue 54 will be drawn into the socket 14 in a substantially airtight relation, so as to be held forward of its normal resting position, thus bringing the body of the tongue also forward from its usual proximity to the soft palate 56 and the posterior pharyngeal wall 57. The front plate 16 and the upper and lower troughs 18 and 20 serve to prevent the oral flow of air, while the socket 14, by maintaining the tongue in a forward position, opens the nasal breathing passageway, which prevents soft tissue vibration as air passes through said passage. By restricting the jaw movement, nocturnal tooth grinding is also prevented.
The single-troughed device 10' is substantially identical in operation to the double-troughed device 10, the principal difference being that complete jaw movement is not prevented. However, oral breathing is still substantially eliminated by the curved plate 16' overlying the lips, and the single tooth-engaging trough 18' is sufficient to prevent nocturnal tooth grinding.
PREFERRED FORM OF CONSTRUCTION
In recent experimentation with devices of the type disclosed hereinbelow, I discovered that a simpler device could be provided for securing the anti-snore and anti-bruxism advantages sought. FIGS. 5-7 disclose the improved device discovered by my research.
In FIG. 5, the improved device is a unitary, formed body, generally indicated at 100 and is shown mounted in the mouth of a user. For purposes of reference, the user's upper lip is shown at 102, the lower lip at 104, the upper tooth arch at 106, the upper, or hard palate at 108, the lower tooth arch at 110 extending upwardly from lower gum 112, and the tongue is generally indicated at "T" as shown in FIG. 5.
The imperforate air flow preventing means of device 100 is of a size and shape to have a forward and outer portion 114 to protrude between the user's lips 102 and 104. The device 100 is also shaped to provide an elongated, rearward, socket means, generally 116, having a forward closed end and a rearward open end into which a portion of tongue "T" is inserted.
The vertical axial cross-section illustration in FIG. 5 discloses that the exterior of the air flow preventing means 100 is shaped to provide therein upper and lower recesses that are adapted for receiving thereinto forward portions of said upper and lower dental arches which engage that device 100 to hold same in position and to limit rearward movement thereof further into the mouth of the user. The device 100 may be removed from the mouth of the user by spreading the jaws and disengaging same from the teeth and then pulling the device forwardly out of the mouth.
The teeth-receiving upper recess is indicated at 118 and the teeth-receiving lower recess is indicated at 120. Bounding the forward portion of said upper recess 118 is a flange 122 that fits between the upper lip 102 and the forward portion of the upper teeth and gum arch. Rearwardly of said forward portion of the upper teeth arch 106 is an upper shelf 124, that is shaped to bound a rearward portion of the elongated socket means 116 and to lie closely adjacent in spaced relation to, or even directly abutting, the upper hard palate 108. The portions of the body 100 that bounds said lower recess 120 include a forward flange 126 which fits between the lower lip 104 and the forward portion of the lower tooth arch 110, and a lower shelf 128. The upper shelf 124 extends rearwardly into the mouth of the user a greater distance than the lower shelf 128.
With respect to the elongated socket means 116 defined in body 100, it is preferred that there be a constriction therein whose location is indicated generally at 130 that is spaced axially between the front and rear ends of said socket means 116 and closer to the front end of the socket means than to the rearmost end of the socket means. The purpose of this constriction 130 is to generally duplicate a constricted neck of an opening, such as is found in the mouth of a soft drink bottle, so that when air has been evacuated from the forward portion of the socket means 116, only the tip of the tongue enters into the portion of socket 116 forwardly of constriction 130 and is held by the constriction or neck 130 in that position, thus drawing the tongue forwardly to the position seen in FIG. 5.
With respect to the actual device produced by my experimentation, FIGS. 6 and 7 illustrate generally the type of shape that the exterior of the air flow preventing means will take. Thus, in FIG. 6 it will be seen from the rear view that the shape is generally ovate in elevation, corresponding with the fact that a person's mouth is laterally elongated relative to the normal vertical spacing of the lips. Also, the upper flange 122 and upper shelf 124 are of varying peripheral shape selected to perform their respective functions. The upper flange 122 merges with the side portions 132 and 134 that are selected to be of a dimension to engage the buccal portions of the mouth. The rearward portion of the socket means 116 has an ovate shape that is laterally elongated and vertically reduced as seen at 136 with a central crease 138 in the lower wall to accommodate the structure of the bottom of the tongue T. The constriction seen in FIG. 6 is indicated generally at 130 and is located forwardly within the elongated socket means 116. The upper shelf 124 is of sufficient width to comfortably accommodate the upper tooth arch 106.
FIG. 7 is a side perspective view taken partly from the rear and illustrates more clearly both the nature of the upper recess 118, for receiving the forward portion of the upper tooth arch 106, and the relative proportioning and appearance of the upper flange 122 and upper shelf 124. The upper shelf 124 is not required to contact upper palate 108 or the upper gum portion of the arch 106, but does provide an inner surface that makes suction contact with the tongue.
The forward flange 126 is thinned or tapered to provide a comfortable fit with and against the gum of the lower tooth arch 110. The height of the side portions 132 and 134 (seen in FIG. 6) is selected so as to fit comfortably between the upper and lower teeth and to provide at their inner surfaces a seal with the tongue.
The device 100 cannot be used by a person that is unable to breathe freely through his nasal passageways. However, use of the device has exhibited initial promise as a prosthesis for aiding in avoidance of, or obviating, problems associated with sleep apnea in elderly persons, wherein cases have been reported where the person's tongue is swallowed, leading to suffocation.
While the protrusion of the body 100 from between the lips 102 and 104 may be exaggerated in FIG. 5 for purposes of illustration, I have determined that the length of the socket means 116 and thickness of wall body 100 at the forward end, extending forwardly of the tooth line, need not be in excess of only about 5/8".
While particular forms of my invention have been disclosed and described, it will be understood that the invention may be utilized in other forms and for other purposes, so that the purpose of the appended claims is to cover all such forms of devices not disclosed but which embody the invention disclosed herein.
As noted earlier above, the body 100 is preferably formed from a synthetic plastic resin that displays the property that renders the plastic more pliable when warmed to a relatively low temperture above body temperature, with solidification occurring as the resin is cooled to body temperature. One such resin is ethylene vinyl acetate. | A device is provided for positioning within the mouth of a user for preventing snoring and nocturnal tooth grinding. The device is an integrally molded body. The device provides dental engaging portions and a rearwardly-opening central socket for cooperating with the forward portion of the user's tongue in a manner to draw the tongue forwardly so as to increase the unobstructed dimension of the nasal breathing passage. When operatively positioned within the mouth, some of the user's upper and lower teeth will enter into recesses provided by the device. The device substantially eliminates oral breathing. The tongue will be held in the socket by a negative pressure developed in the socket. When the tongue is held, it draws the body of the tongue forwardly of its usual restive position behind the lower teeth and adjacent the soft palate, the uvula and the posterior pharyngeal wall, thereby increasing the dimension of the air flow passage through the naso-pharynx to facilitate nasal breathing. The device's engagement with at least portions of one of the user's dental arches operates to eliminate nocturnal tooth-grinding. | 0 |
BACKGROUND OF THE INVENTION
The present invention relates to a fluid flow control system, assembly and method and, more particularly, to a system, assembly and method utilizing reeled tubing for controlling the flow of fluid in oil and gas earth wells.
In the operation of subterranean oil and gas earth wells, it is often necessary to control the flow of fluid through the production tubing and into the annulus between the tubing and the wellbore casing. For example, in stimulation techniques the wellbore casing passes through a formation in the earth well and a pressurized fluid is passed through the production tubing and then laterally through appropriate openings formed in the tubing into the annulus between the tubing and the wellbore casing. Perforations are provided in the latter casing for directing the fluid into the formation for stimulating the recovery of oil and gas.
Known techniques of this nature employ threaded tubing for selective conveying of the fluid from the ground surface to the perforated casing. Although reeled tubing has been used in connection with production tubing to perform other functions there has been no known effective use of reeled tubing for conveying stimulation fluid into the annulus between the production tubing and the casing probably due to the need for relatively sophisticated high pressure sealing and blow-out prevention techniques. There is a need for reeled tubing in these types of operations since the reeled tubing has several advantages. For example, it can be more rapidly inserted into the well and can be more easily passed through downhole equipment. Also, the reeled tubing can traverse highly deviated, or horizontal, wells which could otherwise not be traversed with wireline or threaded tubing in a controlled manner.
SUMMARY OF THE INVENTION
It is therefore an object of the present invention to provide a fluid flow control system, assembly and method for oil and gas wells.
It is a further object of the present invention to provide a system, assembly and method of the above type which is adapted for use with reeled tubing.
It is a still further object of the present invention to provide a system, assembly and method of the above type in which the flow of the fluid from the reeled tubing can be selectively controlled.
It is a still further object of the present invention to provide a system, assembly and method of the above type in which can be used in vertical, deviated, or horizontal wells.
It is a still further object of the present invention to provide a system, assembly and method of the above type which can be used to perform stimulation, injection or formation testing operations using reeled tubing.
Toward the fulfillment of these and other objects, the assembly of the present invention uses a sliding sleeve valve connected in a string of well tubing which is inserted in the wellbore casing. A straddle assembly is provided within the sliding sleeve valve for sealing against axial flow of fluid and isolating a lateral fluid flow path. A stinger assembly is provided which receives reeled tubing, is insertable within the straddle assembly and functions to lock the stinger assembly and reeled tubing relative to the straddle assembly and the sleeve valve. The sliding sleeve valve functions to selectively control the lateral flow of stimulation or formation testing fluid through the assembly into the annulus between the assembly and the wellbore casing.
DESCRIPTION OF THE DRAWINGS
The above brief description, as well as further objects, features and advantages of the present invention will be more fully appreciated by reference to the following detailed description of the presently preferred but nonetheless illustrative embodiments in accordance with the present invention when taken in conjunction with the accompanying drawings wherein:
FIGS. 1A-1C are longitudinal sectional views of the sliding sleeve valve of the present invention with FIG. 1B being a downward continuation of FIG. IA and FIG. 1C being a downward continuation of FIG. 1B;
FIGS. 2A-2D are longitudinal sectional views of the entire flow control assembly of the present invention inserted in a wellbore casing with FIG. 2B being a downward continuation of FIG. 2A, FIG. 2C being a downward continuation of FIG. 2B, and FIG. 2D being a downward continuation of FIG. 2C;
FIG. 3 is a developed view of the indexing sleeve of the control assembly of the present invention; and
FIG. 4 is a schematic view, partially in elevation and section, and partially broken away, of an earth well, showing the system and assembly of the present invention installed in a wellbore casing.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to FIGS. 1A-1C, the reference numeral 10 refers in general to a sliding sleeve valve comprising an upper tubular housing 12 and a lower tubular housing 14 each of which has a stepped outer diameter and inner diameter. An intermediate tubular housing 16 extends between the upper housing 12 and the lower housing 14. The upper and lower end portions of the upper housing 12 are stepped and are provided with a plurality of external threads to enable the upper end portion to be connected in a string of well tubing (not shown) and to enable the lower end portion to receive and engage an overlapping threaded upper end portion of the intermediate housing 16. Similarly, the lower end portion of the intermediate housing 16 is in threaded engagement with the upper end portion of the lower housing 14 and the lower end portion of the latter housing is externally threaded for connection in the string of well tubing, as will be described.
The valve 10 is positioned relative to a wellbore casing 20 located in an earth well and having a plurality of axially and angularly spaced perforations 20a. As described in detail later, the valve 10 is normally connected between two sections of production tubing (not shown), and packers, or the like, are spaced above and below the valve 10 to isolate zones in the casing 20 for selective stimulation of the oil and gas reservoirs adjacent the casing or for other similar functions.
An annular packing 22 extends between the lower end of the upper housing 12 and an inwardly directed annular flange 16a formed on the intermediate housing 16. Similarly, an annular packing 24 extends between the upper end of the lower housing 14 and another inwardly-directed annular flange 16b formed on the intermediate housing 16 in a spaced relation to the flange 16a. A plurality of angularly-spaced openings 16c (one of which is shown) are provided through the intermediate housing 16 and extend between the packings 22 and 24.
The inner bores of the upper housing 12 and the lower housing 14 ar shown by the reference numerals 12a and 14a, respectively and are stepped to define a pair of shoulders 12b and 14b and a continuous enlarged bore extending therebetween. The latter bore receives a sliding sleeve 26 the outer diameter of which is slightly less than the inner diameter of the enlarged bore and the packings 22 and 24. The sleeve 26 is adapted for slidable movement between a closed position shown in FIGS. 1A-1C, in which the upper end of the sleeve 26 engages the shoulder 12b, and an open position (shown and further described in connection with FIGS. 2A-2D) in which the lower end of the sleeve 26 engages the shoulder 14b.
Three axially spaced annular detents 14c, 14d and 14e are provided in the inner surface of the lower housing 14 and are adapted to be engaged by an annular raised portion 26a formed on the outer surface of the sleeve 26. In the closed portion of FIGS. 1A-1C the raised portion 26a extends in the detent 14c.
A plurality of angularly-spaced openings 26b (one of which is shown) are provided through the sleeve 26 which, in the closed position of FIG. 1, are axially-spaced from the openings 16c in the intermediate housing 16. Similarly, a plurality of angularly spaced, relatively small-diameter passages 26c are provided through the sleeve 26 for reasons to be described.
The sliding sleeve valve 10 is located in the string of well tubing and relative to the casing 20 so that the openings 16c are axially aligned with the perforations 20c in the casing.
FIGS. 2A-2D depict the entire fluid control assembly of the present invention, including the sliding sleeve valve 10, mounted in the casing 20. After the valve 10 is positioned in the casing 20 in the location described above, the sleeve 26 is moved downwardly to its open position in a manner to be described. A tubular straddle isolation assembly 30 is then inserted in the bore of the valve 10 in a coaxial relation thereto also in a manner to be described. The straddle assembly 30 includes an upper locking mandrel assembly 32, a straddle mandrel 34 connected to the lower end of the mandrel 32, a packing sub 36 connected to the lower end of the straddle mandrel 34, an equalizer sub 38 connected to the lower end of the packing sub 36 and a cap 40 connected to the lower end of the equalizer sub 38.
All of these components making up the straddle assembly 30 are tubular and thus define a continuous bore which is closed at its lower end by the cap 40. Also, all of these components have stepped inner and outer surfaces and their respective end portions are in a telescoping, or overlapping, relationship and are connected together by cooperating internal and external threads respectively provided thereon and O-ring seals extending therebetween. Since these type of connections are conventional they will not be described in any further detail.
The locking mandrel assembly 32 includes a fishing neck 42 having an enlarged end portion 42a and an expander sleeve 44 in threaded engagement with the lower end portion of the fishing neck. A portion of the expander sleeve 44 extends within the upper end portion of a locking sleeve 46 having three angularly-spaced elongated openings, or windows, 46a (only one of which is shown). Each of the windows 46a receives a locking key 48 having a stepped outer surface which, in the locking position shown, extends through its respective window and into corresponding grooves 12c and 12d formed in the inner bore of the upper housing 12. It is understood that three leaf springs (not shown) are provided between the expander sleeve 44 and the locking sleeve 46 and that each leaf spring is bent so that its upper portion extends radially in a slot (not shown) formed in the locking sleeve 4 and its lower end portion extends underneath a corresponding key 48 to urge the keys radially outwardly into the locking position shown. The expander sleeve 44 can then be moved downwardly to the position shown to lock the keys 48 in the locking position shown. A retainer sleeve 50, having a stepped outer surface, receives the expander sleeve 44, the locking sleeve 46 and the keys 48, and is connected, at its lower end portion, to the straddle mandrel 34.
Since the locking mandrel 32 is conventional and is more specifically described in U.S. Pat. No. 3,208,531, assigned to the same assignee as the present invention, it will not be described in any further detail.
An annular packing 54 extends between a shoulder defined by the stepped outer surface of the sleeve 50 and the upper end of the straddle mandrel 34, and an annular packing 56 extends between a shoulder defined by a stepped outer surface of the packing sub 36 and the upper end of the equalizer sub 38. The packings 54 and 56 are designed to provide a tight fit with the corresponding surface of the side door valve 10 to withstand and seal against relatively high fluid pressures.
A plurality of angularly-spaced openings 34a (one of which is shown) are provided through the mandrel 34 which are in axial alignment with the openings 16c in the housing 16 of the side door valve 10 and with the openings 26b of the sleeve 26 in the open position of the sleeve shown in FIG. 2.
A plurality of angularly-spaced, radially-extending indexing pins 58 (one of which is shown) extend through an opening in the straddle mandrel 34 in threaded engagement therewith. The pins 58 project inwardly into the bore of the mandrel 34 and their function will be described later.
The equalizer sub 38 has a radial passage 38a extending therethrough which is normally blocked by an equalizer valve 59 having two spaced O-rings 59a and 59b engaging the inner bore of the sub. A plurality of slots are formed in the lower end of the valve 59 to form resilient fingers 59c which normally rest on a beveled internal shoulder 38b of the sub 38.
The reference numeral 60 refers, in general, to a tubular stinger assembly having a portion extending within the bore of the straddle assembly 30. The upper portion of the stinger assembly 60 includes an upper housing 62 having an internally threaded upper end portion for connection to reeled tubing (not shown). The housing 62 extends over an inner mandrel 64 having a chamfered end 64a and an annular groove 64b. A plurality of shear pins 65 (one of which is shown) extend through angularly-spaced openings formed through the upper housing 62 and into an annular groove formed in the outer surface of the inner mandrel 64 to normally prevent relative axial movement between the housing and the mandrel.
A valve housing 66 extends over the lower end portion of the upper housing 62, and a plurality of angularly-spaced retaining lugs 68 (one of which is shown) extend from the inner mandrel 64, through corresponding openings found in the upper housing 62 and into an annular groove formed in the inner surface of the valve housing 66. The lugs 68 normally prevent axial movement of the upper housing 62 relative to the valve housing 66 but permit an emergency release of same as will be described. A ball valve 69 is sized to rest on the chamfered end 64a of the inner mandrel 64 for reasons to be described.
A fishing neck 70 projects upwardly from the valve housing 66 with its lower end portion in threaded engagement with the upper end portion of the latter housing. The upper end portion of a cross over sub 72 is in threaded engagement with the lower end position of the valve housing 66, and a valve cage 74 is secured between the lower end of the valve housing 66 and a shoulder formed by a stepped inner surface of the crossover sub 72. The body portion of the valve cage 74 is spaced slightly radially outwardly from the corresponding inner surface of the valve housing 66 to define an annular passage P1 and a plurality of openings 74a (one of which is shown in FIG. 2a) in communication with the latter passage. The upper end of the valve cage 74 is chamfered for receiving a ball valve 76 which moves between the latter end and a beveled shoulder 66a formed on the inner surface of the valve housing, for reasons that will be explained.
The stinger assembly 60 also includes a packing sub 80 connected to the lower end portion of the cross-over sub 72, a circulating sub 82 connected to the lower end of the packing sub and a retainer cap 84 extending over the lower end portion of the circulating sub. All of these components are tubular, have stepped inner and outer surfaces, and their respective end portions are in a telescoping, or overlapping relationship and are connected together by cooperating internal and external threads respectively provided thereon. Since these types of connections are conventional they will not be described in any further detail.
An annular packing 86 is located between the upper end of the circulating sub 82 and a shoulder 80a formed on the packing sub 80. A plurality of annular-spaced openings 82a (one of which is shown) extend through the sub in axial alignment with the openings 34a of the mandrel 34, the openings 16c in the housing 16 of the sliding sleeve valve 10, and with the openings 26b of the sleeve 26 in its open position.
An indexing sleeve 88 extends between the upper end of the cap 84 and a shoulder 82b defined by the stepped outer surface of the sub 82. The inner diameter of the sleeve 88 is slightly greater than the outer diameter of the corresponding portion of the sub 82, and the outer diameter of the sleeve is slightly less than the corresponding portion of inner diameter of the mandrel 34 to permit rotation of the sleeve for reasons to be described.
As shown in FIG. 3, a plurality of slots 88a are provided in the lower portion of the sleeve 88 which receive the indexing pins 58 and a plurality of slots 88b are provided in the upper portion of the sleeve 88. The sleeve 88 also includes angled cam surfaces 88c and 88d located adjacent the slots 88a and 88b, respectively, for reasons to be described. During downward movement of the sleeve 88 relative to the pins 58, the pins engage the lower cam surfaces 88c, work their way into the grooves 88a (by rotation of the sleeve 88 as necessary), engage the upper cam surfaces 88d and work their way into, and pass through, the grooves 88b until the lower end of the housing 72 bottoms out on the upper end of the fishing neck 42. Upon subsequent upward movement of the sleeve 88, the pins pass back through the grooves 88b, engage the cam surface 88d to cause rotation and orientation of the sleeve 88, and bottom out on the lower ends of the latter grooves, as shown by the dashed lines. This locks the sleeve 88, and therefore the assembly 60, against further upward axial movement relative to the assembly 30. Since this locking technique utilizing this pin groove arrangement is conventional as shown, for example, in U.S. Pat. No. 4,321,965, assigned to the assignee of the present invention, it will not be described in any further detail.
The casing 20 is shown in FIG. 4 passing through a formation 90 in an earth well 92. The reference numerals 94a and 94b refer to an upper section and a lower section, respectively, of a string of well tubing located in the casing 20. The sliding sleeve valve 10 is connected between the tubing sections 94a and 94b in the manner described above.
Two axially spaced packers 96a and 96b extend between the outer surfaces of the well tubing sections 94a and 94b, respectively, and the inner surface of the casing 20. The packers 96a and 96b operate in a conventional manner to anchor and seal the tubing sections 94a and 94b to the casing 20 to form a sealed annular chamber and isolate the perforations 20a in the casing 20 from other axially spaced perforations (not shown) formed through the casing. In this manner, the fluid stimulation operation to be described can be applied to the perforations 20a.
In FIG. 4, the straddle assembly 30 is positioned in the sliding sleeve valve 10 in the manner described above, and the stinger assembly 60 is shown after it has been lowered into the straddle assembly 30. To the latter end, the upper end of the stinger assembly 60 is connected, via an adapter 98 to the lower end of a section of reeled tubing 100 which is stored on a reel 102 above ground and is injected into the casing 20 by an injector 104. It is understood that a manifold (not shown) is provided which includes the necessary pumps, valves, and fluid reservoirs to discharge high pressure stimulation fluid into and through the reeled tubing 100. It is also understood that a wellhead valve (not shown) is used to control vertical access to and fluid communication with the upper well tubing section 94a and blowout preventers, or the like (not shown), can be installed to block fluid flow during emergency conditions. Since these components are conventional they will not be discribed in any further detail.
In operation, the sliding sleeve valve 10 is connected between the two well tubing sections 94a and 94b and the assembly is positioned in the wellbore casing 20, as shown in FIG. 4, i.e., with the openings 16c of the valve 10 in approximate axial alignment with the perforations 20a in the casing 20. The sleeve 26 of the valve 10 is in its closed position shown in FIG. 1B, i.e., with the raised portion 26a of the sleeve 26 in the detent 14c, and the openings 26b axially-spaced from the openings 16c in the intermediate housing 16. A shifting tool, or the like (not shown), is inserted into the casing 20 by reeled tubing or wireline and is lowered until it extends within the side door valve 10. An example of such a shifting tool is disclosed in U.S. Pat. No. 3,051,243, the disclosure of which is incorporated by reference. The shifting tool is adapted to engage the sleeve 26 in a conventional manner and the tool is then moved downwardly relative into the side door valve 10 to slide the sleeve downwardly. This downward movement of the sleeve 26 continues until the raised portion 26a engages in the detent 14e and the lower end of the sleeve abutts the shoulder 14b of the housing 14 as shown in FIG. 2D. In this position, the openings 26b of the sleeve 26 are in axial alignment with the openings 16c of the intermediate housing 16.
The straddle assembly 30 is then connected, above surface, to a suitable running tool, or the like (not shown), the upper end of which is connected to a section of reeled tubing (which may be reeled tubing 100) and the lower end of which is adapted to be quick releasably connected to the fishing neck 42. The running tool can be of the type disclosed in co-pending application Ser. No. 417,282, filed Oct. 5, 1989, and assigned to the assignee of the present invention. The running tool, and therefore the straddle assembly 30, is then inserted into the casing 20 as disclosed in the above-identified application. A prong (not shown) associated with the running tool initially enters the straddle assembly 30 and passes through the bore thereof until it engages the upper end of the equalizer valve 59 and forces it downwardly, which causes the shoulder 38b formed on the equalizer sub 38 to cam the fingers 59c radially inwardly to permit the valve to continue to move downwardly until the lower ends of the fingers engage an internal shoulder 38c of the sub 38. This slideable movement of the valve 59 exposes the opening 38a, and thus permits any well fluid to flow through the latter opening into the interior of the equalizer sub 38 and pass upwardly through the bore of the straddle assembly 30. This fluid can then exit through suitable radial openings (not shown) formed in the fishing neck 42 in order to equalize the pressure across the latter assembly during this downward movement of the assembly 30.
The assembly 30 then enters the inner bore of the valve 10 and continues until it attains the position shown in FIGS. 2A-2D. During this movement, the keys 48 are initially spring biased into the corresponding grooves 12c and 12d. Upon further movement of the fishing neck 42 and the expander sleeve 44 downwardly, the latter sleeve locks the keys 48 in the position shown and prevents further downward movement of the latter neck and sleeve. In this position, the openings 34a in the mandrel 34 are in alignment with the openings 26b and 16c respectively provided in the sleeve 26 and the housing 16, which openings extend between the packing assemblies 54 and 56.
The equalizer valve 59 can then be moved back, by the above mentioned prong, to the position shown in FIG. 2D, i.e. in a position blocking flow through the passage 38a and the prong, along with the above-mentioned running tool, are removed from the wellbore.
As shown in FIG. 4 an end of a section of the reeled tubing 100 is then threaded onto the adapter 98 which is also connected to the housing 62 of the stinger assembly 60. The assembly 60 and the reeled tubing 100 is pushed through the casing 20 and the well tubing section 94a until it enters the upper end portion of the straddle assembly 30 and continues until the pins 58 pass into and through the appropriate grooves 88a in the sleeve 88. Further movement of the straddle assembly, and therefore the sleeve 88, causes the pins 58 to engage the cam surfaces 88d to rotate the sleeve into proper orientation until the pins enter and engage the upper end portions of the grooves 88b as shown by the solid lines in FIG. 3, as described above. It is noted that, just prior to the pins 58 engaging the surfaces defining the upper ends of the grooves 88b, the lower end of the crossover sub 72 contacts the upper end 42a of the fishing neck 42 to eliminate damage to the pins 58.
The operator then pulls up on the reeled tubing 100 and therefore the stinger assembly 60 and the sleeve 88, which causes the pins 58 to move out of the grooves 88b and take the position shown by the dashed lines in FIG. 3, i.e. with the pins engaging the apex of each of the cam surfaces 88d to lock the stinger assembly 60 against further upward axial movement relative to the straddle assembly 30. In this position of the stinger assembly 60, the openings 82a are in alignment with the openings 34a, 26b and 16c as show in FIG. 2C.
Pressurized stimulation fluid can then be introduced, via the reeled tubing 100, through the bore of the stinger assembly 60. Flow through the assembly is blocked by the end cap 40 of the straddle assembly 30 and the packings 54, 56 and 86. Thus, the fluid passes radially through the aligned openings 82a, 34a, 26b and 16c before discharging into the annulus defined between the outer surface of the side door valve 10 and the inner surface of the casing 20. The fluid then will pass through the perforations 20a and into the formation 90 to stimulate same.
During the above operation, the ball valve 76 is forced against the end of the cage 74 by the stimulation fluid as it passes around the ball and through the opening 74a. In the event the well fluid pressure becomes excessive to the extent that it flows upwardly through the bore of the stinger assembly 60, the force of this pressure drives the ball valve 76 against the shoulder 66a to block any further flow upwardly, and thus prevent possible backflow towards the surface. Of course, in situations in which it is desired to permit the backflow of well fluid from the formation, through the aligned openings 16c, 26b, 34a and 82a, into the bore of the stinger assembly 60 and to the reeled tubing 100 for passage to the surface, the valve 76 is not used.
In the event it is necessary to effect an emergency release of the reeled tubing 100 from the stinger assembly 60, the ball valve 69 is dropped into the reeled tubing and is forced against the end 64 aof the inner mandrel 64 under the pressure of the fluid from the reeled tubing. The latter pressure thus builds up against the ball valve 69, and when this pressure is sufficient to exert a force sufficient to shear the pins 65, the sleeve 64 moves downwardly until the groove 64b aligns with the lugs 68. This permits the lugs 68 to move into the groove 64b, thus releasing the housing 62 from the housing 66 and permitting a quick disconnect of the housing 62 and therefore the reeled tubing 100 from the stinger assembly 60. It is understood that a plurality of circulating holes (not shown) are provided through the housing 62, which are axially aligned with, and angularly spaced from, the holes receiving the shear pins 65, to allow for circulation of fluid through the reeled tubing 100 while the latter is being removed from the well.
Removal of the housing 62 exposes the fishing neck 70 which allows a heavy duty workstring (not shown), which may include a pulling tool, an accelerator and a hydraulic jar, to be attached to a reeled tubing and lowered into the casing 20 until the pulling tool engages the fishing neck. Thus a pulling operation can be performed on the stinger assembly 60.
In the event it is desired to remove the assembly of the present invention from the casing 20, the above-described operation is reversed. Thus, the stinger assembly 60 is initially removed from the straddle assembly 30 by pushing down on the reeled tubing, and therefore the sleeve 88, to cause the sleeve to rotate against the pins 58 and align the slots 88a with the pins so that the sleeve 88, and therefore the stinger assembly, can be released from the straddle assembly by pulling up on the reeled tubing. A pulling tool (not shown) is then connected to the reeled tubing and lowered into the casing until it engages the fishing neck 42 of the locking mandrel assembly 32 to permit the straddle assembly 30 to be removed An example of a suitable pulling tool for the purpose is described in copending patent application Ser. No. 345,899, filed May 1, 1989, and assigned to the assignee of the present invention. During the lowering of the pulling tool, a prong associated with the pulling tool can move the valve 59 downwardly to equalize the pressure. The sleeve 26 of the valve 10 is then moved upwardly to its closed position by the shifting tool described above using reeled tubing. During this movement of the sleeve 26, it can be stopped in an intermediate position in which the raised portion 26a engages in the middle detent 14d. In this position, the passages 26c are in alignment with the opening 16c in the intermediate housing 16 to permit any well fluid to flow therethrough and equalize the pressure of the fluid. This is done when the sleeve 26 is closed, and equalization is needed prior to opening.
It is thus seen that the system, assembly and method of the present invention provide an efficient and reliable technique for directing stimulation fluid into and through the perforations in the casing 20 while effectively isolating same from leakage and preventing blow-out.
It is understood that several variations can be made in the foregoing without departing from the scope of the invention. For example, even though the opening of the sliding side door and the setting of the straddle assembly was described as being done utilizing reeled tubing, these operations could also be performed using wireline.
Other modifications, changes and substitutions are intended in the foregoing disclosure and in some instances some features of the invention will be employed without a corresponding use of other features. Accordingly, it is appropriate that the appended claims be construed broadly and in a manner consistent with the scope of the invention. | A fluid flow control system, assembly and method for wells in which a sliding sleeve valve is connected in a string of well tubing in a wellbore casing. The sliding sleeve valve functions to selectively control the lateral flow of fluid through the assembly into the annulus between the assembly and the wellbore casing. A straddle assembly is locked within the sleeve valve assembly for isolating a lateral flow path. A stinger assembly is provided which receives reeled tubing and is insertable to lock within the straddle assembly to create a flow path between the reeled tubing and exterior of the sleeve valve. | 4 |
FIELD OF THE INVENTION
[0001] The present invention is in the field of stakes used to support concrete forms or barriers that are used along the outside of an area in which concrete is to be poured, so as to contain the poured concrete in that area.
BACKGROUND AND DESCRIPTION OF RELATED ART
[0002] Concrete form stakes are typically used to secure wooden boards or “forms” around the perimeter of a concrete pouring area, the stakes driven partway into the ground along the outside face of a form to hold it securely in place before, during, and after the pouring operation. Known stakes come in many shapes and sizes, for example homemade stakes made from scrap wood at the construction site as well as different types of commercial stake made from wood, plastic, and metal.
[0003] Another type of stake used in concrete pouring operations is known as a screed stake, used in spaced pairs to hold screed rods or bars in an even plane across the area to be poured to ensure that the concrete is level and smooth.
[0004] My earlier U.S. Pat. No. 6,588,164, issued Jul. 8, 2003, discloses a stake especially adapted for use as a screed stake, but which can also be used as a form stake. This screed/form stake has a flat rear face and a U-shaped upper cradle portion extending from the front face of the stake, the cradle designed to mate with a separate driver. The driver also has a flat rear face, and a screed-rod-shaped portion that extends from the front face of the driver to mate with a screed rod groove in the cradle portion of the stake. When the lower end of the driver is mated with the stake's upper cradle, the upper end of the driver serves as a pounding surface to drive the stake into the ground. The upper surface of the screed-rod-shaped portion of the driver can be used as a screed rod elevation-measuring surface when seated in the cradle, providing a platform for a transit to measure whether the stake has been pounded in far enough to support a screed rod at the proper height. The screed/form stake has holes formed along its face for securing it to a concrete form with screws or nails. When used as a form stake, the stake is driven home with the same driver used for screeding operations, with the flat back of the driver allowing it to be used against the face of the form without interference. As shown in the patent, the stake can be driven to a point where its cradle is below the upper surface of the form. The stake is typically removed from the exterior face of the form after the concrete has been poured and has set.
[0005] I have a co-pending U.S. patent application Ser. No. 10/957,348 filed Oct. 2, 2004 for a stake designed specifically for use as a form stake. The stake can be pounded or driven into the ground with any non-specialized driving tool, such as a hammer or mallet or even a boot, and naturally levels itself at the top of the concrete form when pounded with such a tool. When the form is no longer needed, the stake can be easily pulled out of the ground with fingers or the claw of a hammer or tool. The form stake has a relatively wide, flat body with a flat rear face, and a forward-facing T-shaped flange structure extending from the front face of the stake. The T-shaped flange structure has a horizontal driving shelf with a uniform, level impact surface at the top of the stake, and a central vertical rib section extending downwardly from the driving shelf with a depth equal to the depth of the shelf protruding beyond the face of the stake. The driving shelf forms the top surface of the stake. The vertical rib bisects the stake. In a preferred form, the underside of the driving shelf has a predominantly perpendicular or acutely-angled surface on both sides of the central rib for grasping with the fingertips or hooking with a tool to pull the stake out of the ground. Although the form stake is lighter and less expensive to manufacture than my previous screed/form stake, it is easier and faster and stronger to use as a form stake.
[0006] Perhaps the most common type of concrete form stake is a simple nail stake, which looks and functions like a giant nail, except that it typically has a number of holes formed along the shank of the nail for securing it to a wooden form board.
[0007] Nail type stakes are often used for other purposes, most notably as tent stakes, since they easily penetrate even the hardest ground. When used as tent stakes, nail stakes are sometimes provided with a cross-piece frictionally held in place on the upper end of the shank below the nail-head to provide a pull handle and a place to tie guy-lines from the tent.
BRIEF SUMMARY OF THE INVENTION
[0008] The present invention is a form stake with a narrow ground-penetrating shank terminating at its upper end in a wider, horizontal, integral driving shelf that allows the stake to be pounded or driven into the ground with any non-specialized driving tool, such as a hammer or mallet or even a boot, and naturally levels itself at the top of the concrete form when pounded with such a tool. When the form is no longer needed, the stake can be easily pulled out of the ground with fingers or the claw of a hammer or tool. The driving shelf has a wide, uniform, level impact surface at the top of the stake, the preferably cylindrical ground-penetrating shank extending downwardly from the center of the driving shelf and tangentially aligned with a flat, rear, form-abutting edge of the driving shelf. In a preferred form, the shank has a diameter or width equal to the front-to-back depth of the driving shelf. The outer ends of the driving shelf extend freely beyond and above the shank body.
[0009] In a further form of the invention, the underside of the driving shelf has a pair of opposing force-transferring flanges extending downwardly and inwardly at an acute angle to an upper end of the shank. The flanges are thin-walled and centered on the underside of the driving shelf. In a preferred form, the flanges extend from an intermediate portion of the underside of the driving shelf, such that the outer ends of the shelf extend beyond the uppermost portions of the flanges.
[0010] In a further form of the invention, the shank portion of the stake is cruciform in section, with the force-transferring flanges merging into two side ribs of the cruciform shank.
[0011] The present form stake is lighter and less expensive to manufacture than my previous form stake, is easier and faster to use as a form stake, and is less likely to wander or cant when driven into hard ground.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] FIG. 1 is a perspective view of two form stakes according to the invention, one prior to being driven into the ground against a wooden form, and the other driven in level with the top of the form.
[0013] FIG. 2 is a front elevation view of a stake as shown in FIG. 1 .
[0014] FIG. 3 is a side elevation view of the stake of FIG. 1 , partially driven into the ground against the outside face of a concrete form.
[0015] FIG. 4 is a side elevation view similar to FIG. 3 , but with the stake fully driven into position adjacent the concrete form.
[0016] FIG. 5 is a top plan view of the stake of FIG. 4 driven into the ground against the face of the form, with the shank portion of the stake shown in hidden lines.
[0017] FIG. 6 is a side elevation view similar to FIG. 3 , but shows the stake being pulled from its fully driven position by hand.
[0018] FIG. 7 is a perspective view of a stake similar to the stake in FIGS. 1-6 , but with a cruciform shank.
[0019] FIG. 7A is top plan view of the stake of FIG. 7 , with the cruciform shank section shown in hidden lines.
DETAILED DESCRIPTION OF THE INVENTION
[0020] Referring first to FIGS. 1 and 2 , the invention is illustrated in a first illustrative example as form stake 10 . Stake 10 is preferably molded as one piece from a suitably strong plastic material, for example a nylon or ABS plastic, although other plastics and materials such as wood or metal can be used, and although the stake is not limited to one-piece construction. Stake 10 is used to laterally secure a wooden form 12 in place around an area in which concrete 13 is to be poured. As shown in the Figures, stake 10 is driven into the ground with its rear surface against the outer face of form 12 to prevent the form from shifting during pouring or curing of the concrete against the opposite inner face of form 12 . The length of stake 10 can vary from under a foot to several feet in length, but in the illustrated embodiment is on the order of twelve to fourteen inches in length.
[0021] Stake 10 has a cylindrical ground-penetrating shank 16 terminating at its upper end in a flat, horizontal driving shelf 18 formed as an integral part of the stake, whether by molding, welding, mechanical attachment, or some other method for giving the driving shelf 18 a permanent, non-rotating, fixed driving connection to shank 16 . The lower end of shank 16 preferably terminates in a point 16 a that helps the shank penetrate hard ground.
[0022] As best seen in FIGS. 2 through 4 , driving shelf 18 has a flat top surface 18 a , a flat bottom surface 18 b , a rear edge 18 c flush at 17 with the tangentially rear-most portion 16 b of shank 16 , and a front edge 18 d flush at 17 with the tangentially front-most portion 16 c of shank 16 . Driving shelf 18 extends beyond both sides of shank 16 , in the illustrated embodiment having a width (for example, 2.875 inches) at least three times the diameter (for example, 0.875 inches) of shank 16 . The flat top surface 18 a of driving shelf 18 forms the upper end of the stake, with a surface area greater than the cross-sectional area of shank 16 . As best shown in FIG. 5 , when stake 10 is viewed from above, the relatively wide, flat, upper face 18 a of driving shelf 18 is the only visible surface, overlying the circumference of shank 16 , and therefore presenting a significantly greater driving face. FIG. 5 shows the tangential or flush alignment of the rear-most and front-most vertical edges or surfaces 16 b , 16 c of shank 16 with the rear and front edges 18 c and 18 d of the driving shelf, allowing the form-facing side of stake 10 to present a smooth, unbroken sliding face to form 12 as stake 10 is driven into the ground against the form until the rear edge 18 c of the driving shelf is against the form. While a perfectly smooth, flat, uniform upper surface 18 a is preferred, it will be understood that minor variations such as different textures or surface finishes or patterns that leave the upper surface generally flat relative to the driving force and the top of the concrete form are acceptable. It will be understood that if both the rear and front edges 16 b and 16 c of the shank are flush with the rear and front driving shelf edges 18 c and 18 d as shown in FIG. 5 , stake 10 can be used reversibly against form 12 .
[0023] The junction of the upper end of shank 16 and the lower surface of driving shelf 18 is reinforced with angled fillets or flanges 20 extending from intermediate portions of the underside of the driving shelf to the sides of the upper end of shank 16 , centered on the underside of the driving shelf 18 in alignment with the long axis of the shelf. Flanges 20 are preferably molded in one piece with the rest of stake 10 . Flanges 20 are also preferably thin-walled, as illustrated, allowing an essentially tangential connection to the sides of shank 16 , and providing room for fingers or a tool to grasp the underside of shelf 18 in the vicinity of the flanges. Flanges 20 efficiently transfer driving force from regions of the driving shelf 18 on either side of shank 16 into the shank, reducing stress at the junction of shelf and shank, and helping to keep the shank driven straight down even when the driving force is off-center.
[0024] Referring to FIGS. 3 and 4 , stake 10 can be pounded into the ground with any non-specialized tool, for example the illustrated mallet 30 , since the upper driving surface 18 a of the stake is a flat, wide, uniform force-distributing surface. No specialized driving tool is necessary, and, in soft soil, foot and even hand pressure (with body weight behind it) may be used to push against the relatively wide, even surface of the driving shelf. Driving the stake with non-specialized tools is accordingly both effective and comfortable, whether using a hammer, a mallet, a rock, a board, a boot, a hand, or any other convenient implement.
[0025] As best shown in FIGS. 1 and 4 , stake 10 tends to automatically level itself both vertically and side-to-side at the upper surface 12 a of form 12 , since a non-specialized driver (especially a driver with a driving or impact face wider than the depth of shelf 18 ) will tend to hit the upper surface 12 a of the form when the flat upper surface 18 a of driving shelf 18 is even with the upper surface of the form. Assuming that the overall length of stake 10 allows a sufficient portion of the stake to be driven into the ground for good holding power relative to the ground, leaving the stake's upper end 18 approximately even with the upper edge of form 12 provides the strongest possible support for the form. Leaving the upper surface of the stake 10 even with the top of form 12 also ensures that concrete smoothing tools can be run across the top of the form without interference. The overall jobsite is also given a neater, more professional appearance with all form stakes driven in evenly against the forms. And the risk of overdriving the form stake to a point where it becomes difficult to remove from the ground is reduced or eliminated.
[0026] Referring next to FIG. 6 , stake 10 is also easily pulled out of the ground when the concrete forming operation is done. The lower surface or underside 18 b of driving shelf 18 is preferably perpendicular to the shank 16 of stake 10 so that maximum pulling force can be exerted on the stake through the shelf with the fingers or a tool hook or claw, as shown. The lower surface 18 b can also be angled inwardly at an acute angle to the front face of stake 10 (not shown), for an even better hooking action on the shelf when the stake is being pulled from the ground. While the lower surface 18 b is preferably flat and uniform as shown, it is possible to vary the contour so long as significant gripping or hooking portions are perpendicular or acute.
[0027] Holes 22 through shank 16 allow the stake to be secured to the face of form 12 in known manner, for example with nails or screws driven through holes 22 into the face of the form. Holes 22 preferably pass through shank 16 perpendicular to rear and front edges 18 c and 18 d of shelf 18 , and therefore perpendicular to a form 12 being supported by a driven stake 10 . Holes 22 could also be acutely angled, but angles greater than 45° tend to put nails or screws inserted through the holes at an ineffective angle relative to the face of form 12 .
[0028] Referring to FIG. 6 , although the thin walls of flanges 20 leave room for fingertips to hook the underside 18 b of shelf 18 on either side of the upper end of shank 16 , upper portions of flanges 20 extend only partway toward outer ends 18 e of the shelf, allowing fingers or a hooking tool to wrap fully under (and even around the outer ends of the shelf 18 when the shelf reaches a point higher than form 12 ) for a better grip, as shown in phantom. This gives the person removing stake 10 the ability to exert both a very strong vertical pulling force, but also creates a moment arm relative to the shank body to provide side-to-side leverage to rock or loosen the shank to help free the stake from difficult ground. This is useful where the stake becomes firmly lodged in the ground, for example if a rough shank surface finish or holes 22 attract concrete dust or moist or compacted dirt or snow that can cement or freeze the stake into the ground.
[0029] Referring next to FIGS. 7 and 7 A, a modified version of stake 10 is illustrated at 100 , having a cruciform-section shank 116 , a driving shelf 118 essentially the same as shelf 18 in FIGS. 1-6 , and force-transferring flanges 120 similar to previously-described flanges 20 . The cruciform shank 116 , centered under driving shelf 118 and having a narrow, ground-penetrating body, will generally be lighter than cylindrical shank 16 if made from the same material, and may have some advantage in penetrating and holding in certain types of soil. The diameter of shank 116 and its relationship to driving shelf 118 is preferably similar to that of shank 16 and shelf 18 , with the same tangential alignment of the rear and front ribs 116 c and 116 d with the rear and front edges 118 c and 118 d of driving shelf 118 , and the same proportion of shelf width to shank diameter. The side ribs 116 e of shank 116 lend themselves to being extended to form (or to merge with) flanges 120 at the upper end of the shank.
[0030] It will be understood that while the circular and cruciform shanks 16 and 116 illustrated above are currently preferred, other cross-sectional shapes are possible, provided that at least the central rear edge or tangent of the shank body centered relative to drive shelf 18 is flush or tangential with the center of the rear form-facing edge 18 c of shelf 18 . It will also be understood that while a rectangular shelf 18 is preferred, other symmetrical shapes with a flat rear form-facing edge are possible. And while the illustrated embodiments show single front and rear vertical edges or surfaces of the shank body aligned with the front and rear edges of the driving shelf 18 , it is possible to align multiple front and rear edges of surfaces of a shank body with central portions of the front and rear edges of driving shelf 18 , for example by rotating the cruciform shank body 116 of FIGS. 7 and 7 A approximately 45°.
[0031] It will be understood that the length and width and relative dimensions of shank 16 and driving shelf 18 can vary according to the anticipated height of the forms with which it will be used, the nature of the ground into which stake 10 will be driven, and the weight or force of concrete that is anticipated against the form.
[0032] While stake 10 is especially designed for use as a form stake, it may find use in other applications for providing good holding power against significant forces in loose soil or sand or even snow.
[0033] It will be understood that the disclosed embodiment is representative of a presently preferred form of the invention, but is intended to be illustrative rather than definitive of the invention. The scope of the invention is defined by the following claims. I accordingly claim: | A form stake having a narrow vertical shank body terminating at its upper end in a wider, flat driving shelf whose outer ends extend far enough from the shank body to provide grasping or hooking surfaces on the underside of the driving shelf spaced from the shank. At least a rearmost edge or surface of the shank is aligned flush with the rearmost edge of the driving shelf, allowing the entirety of the stake to be driven smoothly down into the ground adjacent the face of a form board. In a preferred form the stake includes reinforcing flanges extending from the underside of the driving shelf to an upper end of the shank, the flanges terminating short of the outer ends of the driving shelf. | 4 |
CROSS-REFERENCE TO RELATED APPLICATION
Claim is made of the benefit of the filing date of U.S. Provisional Patent Application No. 61/111,828, filed on Nov. 6, 2008, pursuant to 35 U.S.C. §119(e).
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
This invention was made with Government support under NIH-SBIR Grant 5-R44NSO48734-03 awarded by the National Institute of Health. The Government has certain rights in this invention.
FIELD OF THE INVENTION
The invention relates to a therapeutic intervention to reduce central nervous system (CNS)-mediated pain.
BACKGROUND OF THE INVENTION
Significant pain in cases of spinal cord injury (SCI) or traumatic brain injury (TBI) is quite common, with an estimated 52-58% of TBI patients reporting chronic pain (Sherman et al. 2006). Headache is the most common symptom, but symptoms suggestive of neuropathic pain are also common, sometimes extending into the neck and regions of the shoulder and back (Uomoto et al. 1993). In this study, pain after TBI occurred in more than one area of the body in 60% of patients. Similarly, in spinal cord injury, around 40% of patients develop persistent neuropathic pain (Baastrup & Finnerup 2008; Yezierski 2005). Neuropathic pain is characterized by spontaneous persistent pain and a range of abnormally-evoked responses, such as allodynia (pain evoked by non-noxious stimuli), and hyperalgesia (an enhanced response to noxious stimuli).
A very common cause of CNS-mediated responses contributing to neuropathic pain is cervical or lumbar nerve root injury (radiculopathy), often a result of whiplash or disc herniation. Nerve roots sit at the junction of the central and peripheral nervous systems (PNS) and contain elements of both nervous systems (Fraher et al. 1987). Both radiculopathic and neuropathic injuries affect cellular mechanisms both locally at the site of injury (that is, the nerve root or nerve), and centrally in the spinal cord. Moreover, the CNS (brain and spinal cord) has been shown to mount cellular and molecular cascades in response to neuropathic and radiculopathic injuries that reflect a perceived injury to the CNS (Hashizume et al. 2000; DeLeo & Yezierski 2001; DeLeo & Winkelstein 2002; Watkins & Maier 2005). Therefore, CNS-mediated pain includes pain with injury originating in the CNS, although it can include pain from injuries that originate in the PNS.
There is a substantial literature on possible interventions, including pharmacological (Basstrup & Finnerup 2008) and physical (acupuncture, heat, electrical) treatments (Kumar et al. 2007). However, all these methods have proved inadequate, and no safe, effective method to treat pain after CNS-mediated responses to neuronal injury has been developed.
Neuropathic pain after CNS injury can have different causes, but activation of microglia and the resulting NO production, and release of pro-inflammatory cytokines is a common mechanism (Huselbosch 2008; Rothman et al 2009b). In addition to its pro-coagulant properties, activation of microglia is one of the many properties of mammalian thrombin, a multifunctional serine protease (Weinstein et al. 2008). Since activation of microglia predicts neuropathic pain, the exposure of CNS tissue to thrombin is contraindicated although it is inevitably produced as a result of blood coagulation subsequent to traumatic injury. Xue et al. (2006) show that thrombin from intracerebral injection of autologous blood in mice produced significant brain damage. Further evidence of thrombin's neurotoxicity on CNS tissue is the neuroprotective effect of thrombin inhibitors (Festoff et al. 2004).
The primary structure of thrombins from various species is highly conserved (Banfield & MacGillivray, 1992). Michaud et al. (2002) compared human and salmon thrombin, and found that they were nearly identical in polymerizing fibrinogen and activating Factor XIII, and similar but not identical in stimulating human platelets. They differed in the greater activity of salmon thrombin at low pH and high salt environments. Sawyer et al. (1999), Wang et al. (2000), and Laidmae et al. (2006) demonstrated the similarity of salmon and mammalian-derived thrombin and fibrinogen as fibrin sealants. When combined with fibrinogen, mammalian thrombin appeared safe for use in the rat CNS (Petter-Puchner et al. 2007), but there was no attenuation of the inflammatory response, and its capability to cause pain was unexamined. Fibrin gels composed of salmon fibrinogen and either human or salmon thrombin were equally effective in enhancing neurite outgrowth from mammalian neurons, and Ju et al. (2007) identified salmon fibrinogen, which differs in amino acid sequence and glycosolation from mammalian fibrinogen, as the beneficial component.
BRIEF SUMMARY OF THE INVENTION
According to an aspect of the invention, a method of alleviating central nervous system-mediated pain includes applying salmon thrombin at a site of neural injury. For example, the neural injury site can be part of the central nervous system and/or part of the peripheral nervous system.
Applying salmon thrombin can include applying a gel that includes salmon thrombin. The gel can also include fibrinogen, for example, salmon fibrinogen, human fibrinogen, or bovine fibrinogen. Alternatively, or in addition, the gel can include polyethylene glycol, a synthetic molecule preparation, collagen, and/or alginates.
Applying the gel can include injecting the gel.
The salmon thrombin can be obtained using any known method from any salmon stock. For example, the method can also include obtaining a salmonid, for example, an Atlantic salmon, that is a progeny of domesticated broodstock that are reared under consistent and reproducible conditions. Blood is obtained from the fish, plasma is separated from the blood, and the salmon thrombin is extracted from the plasma. The salmonid from which the blood can be obtained, for example, sexually immature, in the log-phase of growth, larger than two kilograms, and/or reared by standard husbandry methods. Obtaining blood from the salmonid can include rendering the salmonid to a level of loss of reflex activity and drawing blood from a caudal blood vessel. Prior to rendering the salmonid to a level of loss of reflex activity, the levels of proteolytic enzymes and non-protein nitrogen present in the blood of the salmonid can be reduced. Separating plasma from the blood can include centrifuging the blood. Extracting the salmon fibrin from the plasma can include performing an extraction process on the plasma such that all process temperatures are no greater than 6° C., no cytotoxic chemical residues remain in the one or more plasma components, and no oxidation of plasma lipids occurs. An antioxidant and/or a protease inhibitor can be added to the plasma prior to extracting the salmon thrombin.
Alternatively, the salmon thrombin can be obtained using recombinant technology, or by fractionation.
According to another aspect of the invention, a pain relief substance includes a gel that includes salmon thrombin. The gel can also include fibrinogen, such as salmon fibrinogen, human fibrinogen, or bovine fibrinogen. Alternatively, or in addition, the gel can include polyethylene glycol, a synthetic molecule preparation, collagen, and/or alginates.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 are charts showing mechanical allodynia in the forepaw following nerve root compression, with FIG. 1A showing results from treatment with salmon fibrin and FIG. 1B showing results from treatment with human and salmon thrombin.
FIG. 2 is a series of representative micrographs showing ED1 staining of macrophages at the C7 ipsilateral nerve root at day 7 after sham controls, injury, and injury with salmon fibrin (thrombin plus fibrinogen) treatment.
FIG. 3 is a chart showing the activation of microglia (macrophages) by iba1 staining and ED1 staining in the spinal cord adjacent to the injury site.
DETAILED DESCRIPTION OF THE INVENTION
According to the invention, salmon thrombin is used to significantly reduce pain after neural injury, such as injury to the CNS or PNS, a result that is not possible using mammalian thrombin. The invention utilizes salmon thrombin, a serine protease with molecular weight and enzymatic activities toward coagulation substrates similar to human thrombin. Preferably, the salmon thrombin is obtained from salmon by the methods of Michaud et al. (2002), but may be prepared by any of the well-known commercial methods for preparation of human thrombin such as fractionation (Miller-Andersson et al. 1980) or recombinant technology (Holly et al. 1995). Fibrinogen, preferably from salmon (Wang et al. 2000) or from human or bovine sources using known methods of preparation may be combined with the thrombin.
We used a rat model of mechanical allodynia (behavioral sensitivity) that is generally accepted as mimicking or correlating to human neuropathic pain, and initiating sustained CNS responses that regulate pain originating from injury to the CNS and PNS (DeLeo & Winkelstein, 2002) Hubbard and Winkelstein 2005, 2008; Rothman et al. 2005, 2007, 2009 a,b). We show that injection of salmon fibrinogen and thrombin as a fibrin gel, reduces neuropathic pain after a painful nerve root compression injury. Unexpectedly, we found that salmon thrombin alone, but not human thrombin, produced even greater pain reduction.
Although salmon thrombin may be used alone, it is preferably applied with fibrinogen. The use of fibrinogen offers the benefit of application of both proteins in liquid form with the resulting gel filling the injury site. The gel permits a localized treatment without the concerns that accompany systemic therapy. The thrombin may also be combined with any gel-forming material that is compatible with neural injury repair, such as but not limited to polyethylene glycol, synthetic molecules, collagen, alginates, and other organic molecules and biopolymers.
Example #1
Salmon thrombin was prepared from salmon plasma by the method of Michaud et al, 2002, which is incorporated herein by reference. Salmon fibrinogen was also prepared from salmon plasma by the methods of Wang et al, 2000, which is also incorporated herein by reference. These proteins were lyophilized and then held at less than −20° C. On the day of use, the proteins were rehydrated at room temperature, and then held on ice.
Anesthetized male Sprague-Dawley rats (250-350 g) were subjected to a 15-minute compression of the C7 cervical dorsal nerve root with a 10 gf microclip, an established technique that produces behavioral sensitivity that persists for 3-6 weeks and mimics symptoms of persistent pain (Hubbard et al. 2005). Two groups of rats (N=6 per group) were used to evaluate the effectiveness of the fibrin gel and its components to alleviate pain. In one group of rats no treatment was given at the time of injury. A second group received a fibrin gel prepared from salmon fibrinogen and thrombin at the injury site. The fibrinogen was diluted to a working solution of 6 mgs/ml in low-glucose DMEM (Invitrogen, Inc., Grand Island, N.Y.). Salmon thrombin was also diluted with DMEM to a working solution of 4 NIH units/ml and kept on ice until use. Both proteins were filtered to 0.22μ. Immediately following the compression injury to the nerve root, 20 μl of the fibrinogen solution was pipetted into 20 μl of the thrombin solution, mixed gently, and 20 μl of the fibrin solution was applied directly to the nerve root at the site where the nerve root enters the spinal cord. The fibrin solution was allowed to gel for one minute before the surgical site was sutured. Rats in both groups were followed for seven days, during which time mechanical allodynia was measured in the affected forepaw. Mechanical allodynia was assessed by measuring frequency of paw withdrawals after light touch. Treatment with the salmon-derived fibrin gel significantly decreased behavioral sensitivity in the affected forepaw compared to that of untreated rats (p<0.01) ( FIG. 1 .). In addition, similar decreases in sensitivity were also observed in the contralateral paw, suggesting a potential utility for reducing widespread symptoms of pain.
Example #2
A second study was performed on several groups of rats to investigate mechanisms by which the salmon fibrin was mediating pain relief in this model. Separate groups underwent nerve root compression, each with one of the following treatments: human thrombin, salmon thrombin, medium alone (neural basal media), or no treatment. The effect on pain reduction was mediated by the activity of salmon thrombin but not human thrombin, as shown in FIG. 1 . The charts of FIG. 1 show levels of mechanical allodynia in the forepaw following nerve root compression. FIG. 1A shows that salmon fibrin (thrombin plus fibrinogen) alleviated a measure of pain symptoms; reduction in sensitivity was significant and sustained. FIG. 1B shows that a similar reduction in pain is achieved by salmon thrombin alone but not by human thrombin. Error bars show standard deviation.
The nerve root compression injury does not induce massive bleeding, and the endogenous coagulation factors of the rat are sufficient for hemostasis, but as discussed before, also activate inflammation. Additional clotting activity provided by human thrombin at the site of injury did not alleviate pain compared to medium alone (control), and may even exacerbate the pain response. In contrast, salmon thrombin significantly reduced pain (p<0.005) on all days after treatment. Allodynia after salmon thrombin treatment is statistically indistinguishable from uninjured controls.
Behavioral results showing decreased allodynia after treatment with salmon thrombin alone or combined with salmon fibrinogen given at the site of neural injury demonstrate that the nociceptive and/or inflammatory response is mediated by the salmon thrombin. The neural basal media also decreased allodynia at later time points but to a lesser extent than did the salmon proteins. FIG. 2 is a series of representative micrographs showing ED1 staining of macrophages at the C7 ipsilateral nerve root at day 7 after sham controls, injury, and injury with salmon fibrin (thrombin plus fibrinogen) treatment. As shown, treatment with the salmon fibrin at the time of injury reduced ED1 staining compared to injury. The 100 μm scale bar applies to all micrographs.
Thus, FIG. 2 shows the decreased activation of microglia (macrophages) after treatment with salmon thrombin plus fibrinogen, within the area surrounding the nerve root as evidenced by reduced ED1 staining. This same reduction in ED1 positive cells after treatment was even more pronounced when evaluating the spinal cord, as shown in FIG. 3 . FIG. 3 is a chart showing the activation of microglia (macrophages) by iba1 staining and ED1 staining in the spinal cord adjacent to the injury site. As shown, the activation of microglia shown by ED1 staining is reduced after salmon thrombin treatment. Similarly, density of activated microglia as shown by iba1 staining is reduced to sham levels.
Some ED1 staining was present in the spinal cord of all untreated rats, while none was present for sham. However, in the salmon group, only one rat exhibited any ED1 staining in the spinal cord ( FIG. 3 .). Similarly, using immunohistochemistry (Rothman et al. 2009b), quantitative densitometry indicated a marked reduction of iba1 (another marker of activated microglia) in the spinal cord with staining reduced to sham levels.
These examples address nerve-root pain, a model of CNS-mediated pain with a causative mechanism common to other injuries to the CNS, namely, activation of microglia. An equivalent mechanism in the PNS is activation of Schwann cells (Campana W M, 2007). Therefore, salmon thrombin is likely to show efficacy in the PNS for indications involving pain. | A method of alleviating central nervous system-mediated pain includes applying salmon thrombin at a neural injury site. Applying salmon thrombin can include applying a gel that includes salmon thrombin. The gel can also include fibrinogen, for example, salmon fibrinogen, human fibrinogen, or bovine fibrinogen. The salmon thrombin can be obtained from salmon plasma, or using recombinant technology, or by fractionation. A pain relief substance includes a gel that includes salmon thrombin. | 0 |
FIELD OF THE INVENTION
The present invention relates generally to locking mechanisms and, more particularly, to an electronic locking mechanism adaptable to fit enclosures of varying dimensions, while maintaining minimal power consumption.
BACKGROUND OF THE INVENTION
There are currently many different ways to lock things. One of the most common ways is the key locking mechanism. This type of mechanism is relatively secure and tamper proof. However, it is difficult to re-key a key lock to work with a different key if the original key is lost or stolen. Key locks can also be picked. In addition, it is sometimes inconvenient to keep a key.
Manual and electronic combination locking mechanisms provide many advantages. People may forget the combination, but at least they do not have to keep a key. The problem with manual combination locks such as those found on safes, vaults, lockers, and other enclosures, however, is that parts of the actual locking mechanism are often exposed and thus subject to tampering. In addition, mechanical combination locks require machining to high tolerances to avoid manipulation attacks.
While electronic combination locks are generally not exposed, they have other disadvantages. Electronic locks must keep the strike retracted until the user opens the lock, thus using large amounts of power. Another problem associated with electronic locks is that the strike operation can time out, thus forcing re-entry of the key. If one-time keys are used, access can be denied if the user is slow.
Another disadvantage of both key and combination locking mechanisms is their inability to accommodate enclosures of varying dimensions without having to alter the basic operation of the locking mechanism or having to use multiple locks for long doors.
Therefore, there is a need for an electronic locking mechanism that draws little power and that is adaptable to accommodate a broad range of enclosures.
SUMMARY OF THE INVENTION
One embodiment of the present invention provides an improved electronic locking mechanism that requires little power during operation and that is readily adaptable to fit enclosures of varying sizes without having to change the operation of the locking mechanism. The locking mechanism may be adapted to use two rods, a first and a second. The first rod may be attached to one side (i.e., a fixed portion) of an enclosure. The second rod may be attached to the door or lid (i.e., a movable) side of the enclosure. The first and second rod can be cut to the length necessary to fit the enclosure. Attached to one of the rods, preferably the second rod, are one or more cam wafers which are configured to engage to the first rod to lock the mechanism.
The locking mechanism itself is solenoid driven and can be secured to any one of the cam wafers in order to hold the lock in place. The solenoid is spring actuated and is powered by a battery or some other source of electricity. In the preferred embodiment, the electricity source is located in a module external from the locking mechanism. When the correct combination code is entered through a keypad and electronic controller, the controller energizes the solenoid just long enough for the solenoid to lift the pawl arm. When the pawl arm is lifted, no other force acts on the cam wafer in the locking mechanism. Because of the action of a torsion spring, which is coiled around the second rod with potential energy, when the force of the pawl arm is released from the cam wafer the second rod rotates and the cam wafer rotates and disengages from the first rod.
To lock the mechanism, the user manually pushes on the door or lid of the enclosure. The first rod contacts the cam wafer and, as the user pushes the door or lid shut, the second rod rotates and the cam wafer rotates. An aperture in the cam wafer slips behind a portion of the pawl arm, which comes down like a clamp and locks it in place.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention is illustrated by way of example, and not limitation, in the figures of the accompanying drawings in which like reference numerals refer to similar elements and in which:
FIG. 1 is a perspective view of the locking mechanism shown in the locked position in accordance with one embodiment of the present invention.
FIG. 2A is a top view of the locking mechanism showing a cam wafer engaged with the first rod as would be the case when the locking mechanism is in the locked state.
FIG. 2B is a top view of the locking mechanism showing the cam wafer disengaging from the first rod as the locking mechanism is unlocking in accordance with one embodiment of the present invention.
FIG. 3 is a side view of the locking mechanism in the locked position in accordance with an embodiment of the present invention.
FIG. 4 illustrates various components of the locking mechanism including the cam wafer, the solenoid, the cam spring, the pawl arm, the microswitch and the pawl spring in accordance with an embodiment of the present invention.
FIG. 5 is a perspective view of the lock box, the cam wafer, and the pawl arm components of the locking mechanism in accordance with an embodiment of the present invention.
FIG. 6 is a side view of the locking mechanism showing how multiple cam wafers may be added to the second rod as might be needed when locking a large enclosure.
DETAILED DESCRIPTION
Throughout the following description specific details are set forth in order to provide a more thorough understanding of the invention. However, the invention may be practiced without these particulars. In other instances, well known elements have not been shown or described in detail to avoid unnecessarily obscuring the present invention. Accordingly, the specification and drawings are to be regarded in an illustrative, rather than a restrictive, sense.
Referring now to FIG. 1, there is shown a perspective view of an adaptable electronic locking mechanism configured in accordance with one embodiment of the present invention. The locking mechanism 100 includes a first rod 20 and a second rod 22 . The first rod 20 is a round rod and is attached to one side of an enclosure. The second rod 22 is a hexagonal rod and is attached to the door or lid side of the enclosure. The first rod 20 and second rod 22 are cut to the length necessary to fit the enclosure. Note, in this example the rods have the cross-sectional shapes recited above, but this is not critical to the present invention. Rods of any convenient cross-sectional shape may be used so long as the overall functionality of the locking mechanism remains substantially similar to that described below.
Attached to the second rod 22 is a cam wafer 30 which is configured to engage to the first rod 20 to lock the mechanism. The cam wafer 30 includes a thru-hole 32 through which the second rod 22 may pass. In this way the cam wafer 30 may be secured to the second rod 22 . A u-shaped hole 34 in the cam wafer 30 engages the first rod 20 and is fitted to the diameter of the first rod 20 . A clip on the cam wafer (not shown in this view) extends below the horizontal plane of the body of the cam wafer 30 and engages the torsion spring 40 which is coiled around the second rod 22 below the cam wafer 30 . A portion of the cam wafer 30 may bend downward in a right angle to the main horizontal plane of the cam wafer 30 . The bent portion of the cam wafer 30 may have a u-shaped hole 36 to engage the end of the torsion spring 40 at the base of the locking mechanism 100 and thus provide a self-opening tension for the door.
Circumferential or semi-circumferential grooves (not shown in this view) may be cut into the second rod 22 directly above and below the cam wafer 30 . These grooves can accommodate an upper e-clip 42 and a lower e-clip 44 , which in this example are dome-shaped wafers made of spring steel. The domed portion of the upper e-clip 42 and the lower e-clip 44 is inserted laterally into the respective grooves on the second rod 22 thereby securing the upper e-clip 42 and the lower e-clip 44 to the second rod 22 . The cam wafer 30 is held firmly in place between the upper e-clip 42 and the lower e-clip 44 and is thus prevented from moving up or down the second rod 22 . Similarly, other shapes for the e-clips 42 and 44 may be used. However, regardless of the configuration of the e-clips 42 and 44 , it is desirable to include some method such as press-fittings or set screws to prevent displacement of the cam wafer 30 along the second rod 22 .
The locking mechanism includes a lock box 60 that may be fabricated from stainless steel or other suitable material and shaped to form a three sided housing which may be attached to the inside of an enclosure (not shown in this view). The lock box 60 may be mounted on the rear or inside surface of the enclosure by conventional fastening means, such as screws and bosses. The present invention is useful in a variety of applications. Therefore, the lock box 60 may be mounted to the inside of a safe, a locker, a storage container, a vault, or other types of enclosures.
The lock box 60 encloses a solenoid 10 that can be mounted vertically between an upper flange 70 and a lower flange 72 or other fastening means which are secured to the distal wall of the lock box 60 . A pawl arm 80 is pivotably mounted on a fixed axis (not shown in this view) which is secured to the base of the lock box 60 . The solenoid 10 is positioned in the housing so that the pin 12 of the solenoid 10 may be attached to the frontal portion of the pawl arm 80 . A pawl spring 90 is suspended from a third flange 74 which is secured to the distal wall of the lock box 60 . One end of the pawl spring 90 is secured to the flange 74 . The other end of the pawl spring 90 is secured to the distal portion of the pawl arm 80 .
When tumblers are correctly aligned through the proper combination, key, or other unlocking means such as an electronic controller (not shown in this view) a battery, capacitor, or some other electricity source (not shown in this view) energizes the solenoid 10 momentarily. In the embodiment represented by FIG. 1, the battery is external to the locking mechanism and is part of a module that might also include a key pad, a display screen, a smart-card slot, a barcode reader, a light emitting diode, or a scanner linked to a computer database of authorized individuals and their associated unique personal characteristics such as fingerprints or iris patterns.
When the solenoid 10 is energized the pin 12 retracts and lifts the pawl arm 80 . The frontal portion of the pawl arm 80 has been fabricated to bend downward so that it engages an aperture 36 in the cam wafer 30 to secure the device. When the pawl arm 80 is lifted it disengages from the aperture 36 in the cam wafer 30 . Because of the action of the torsion spring 40 which is coiled with potential energy, when the force of the pawl arm 80 is released from the cam wafer 30 , the energy in the torsion spring 40 starts to release which causes the second rod 22 to rotate and the cam wafer 30 to rotate and disengage from the first rod 20 . The pawl arm 80 rests upon the upper plane of the cam wafer 30 when the mechanism 100 is unlocked and the door is open to indicate an unlocked state.
Preferably, a microswitch 82 may also be fitted to the lock box. The distal portion of the pawl arm 80 depresses the microswitch 82 when the frontal portion of the pawl arm 80 is lifted. This information may be passed through electronic circuitry (not shown in this view) in a manner well known in the art and may be shown in an optional display panel in a module external to the locking mechanism (not shown in this view) to indicate to the user whether the mechanism is in an unlocked or locked state.
To re-lock the enclosure, the user pushes on the door or lid of the enclosure. The first rod 20 engages the cam wafer 30 and, as the user pushes the door shut, the second rod 22 rotates and the cam wafer 30 rotates. The aperture 36 of the cam wafer 30 rotates to reengage the frontal portion of the pawl arm 80 , thereby securing the mechanism.
In the embodiment of FIG. 1, the locking mechanism 100 is made of stainless steel and may be used to lock enclosures of varying materials including but not limited to metal, wood, and plastic. In other embodiments, the locking mechanism may be made of rolled steel, various other metals, composites such as fiberglass, carbon fiber, or plastics. The locking mechanism may also be mounted horizontally in the enclosure, such that the first rod 20 is attached to the door or lid of the enclosure and the second rod 22 is attached to a side of the enclosure.
In still other embodiments, the cam wafer engages 30 directly with a door or lid frame within the enclosure. The locking mechanism in this embodiment thus requires only one rod.
FIG. 2A is a top view of the locking mechanism 200 showing the cam wafer 210 engaged with the first rod 220 as would be the case when the locking mechanism 200 is in the locked state. The second rod 222 passes through the thru-hole 224 in the cam wafer 210 . In this view, the top plane of the solenoid 230 is shown as it is mounted to the upper flange 232 which is secured to the distal wall of the lock box (not shown in this view). The pawl arm 240 is pivotably mounted on a fixed axis 242 to the base of the lock box (not shown in this view). In the locked state, the pawl arm 240 engages an aperture (not shown in this view) in the cam wafer 210 to secure the locking mechanism.
FIG. 2B is a top view of the locking mechanism 250 showing the cam wafer 260 disengaging from the first rod 270 as the locking mechanism 250 is unlocking in accordance with one embodiment of the present invention. The second rod 272 passes through a thru-hole 274 in the cam wafer 260 . In this view, the top plane of the solenoid 280 is shown as it is mounted to the upper flange 282 which is secured to the distal wall of the lock box (not shown in this view). The pawl arm 290 is pivotably mounted on a fixed axis 292 to the base of the lock box (not shown in this view) and is in the lifted state and thus disengaged from the aperture (not shown) in the cam wafer 260 .
FIG. 3 is a side view of the locking mechanism 300 in the locked position in accordance with one embodiment of the present invention. The cam wafer 310 is configured to engage to the first rod 320 . The second rod 322 passes through a hole (not shown in this view) in the cam wafer 310 . The torsion spring 324 is coiled around the second rod 322 below the cam wafer 310 . An alternative embodiment of the pawl arm 330 is disclosed in this view. The solenoid 340 is vertically mounted between two flanges (not shown in this view) secured to the lock box (not shown in this view). A pawl arm 330 is pivotably mounted on a fixed axis 332 at the base of the lock box 350 . The solenoid 340 is positioned so that the solenoid pin 342 may be attached to the frontal portion of the pawl arm 330 . In the locked position, the solenoid coil 344 remains unenergized and the frontal portion of the pawl arm 330 bends downward and engages an aperture 312 in the cam wafer 310 to secure the device. A pawl spring 360 is suspended from a flange (not shown in this view) which is secured to the distal wall of the lock box (not shown in this view). In this embodiment, a microswitch 370 is fitted to the base of the lock box 350 . The microswitch 370 is in the open state and is not depressed by the distal end of the pawl arm 330 .
FIG. 4 illustrates various components of the locking mechanism including the cam wafer 410 , the solenoid 420 , the cam spring (or torsion spring) 430 , an alternative embodiment of the pawl arm 440 , the microswitch 450 , and the pawl spring 460 .
FIG. 5 is a perspective view of the lock box 500 , the cam wafer 510 , and the pawl arm 520 components of the locking mechanism in accordance with an embodiment of the present invention.
In a further embodiment of the present invention as illustrated by FIG. 6, multiple cam wafers 610 , 620 , and 630 may be added to the second rod 640 to increase the security of the locking mechanism, such as might be needed to lock a large enclosure. FIG. 6 is a side view of the locking mechanism 600 in the locked state where an upper cam wafer 610 middle cam wafer 620 and bottom cam wafer 630 are secured to the second rod 640 . The cam wafers 610 , 620 and 630 are configured to engage the first rod 650 . The second rod 640 passes through hole (not shown in this view) in the cam wafers 610 , 620 , and 630 . A torsion spring 612 is coiled around the second rod 640 below the upper cam wafer 610 and a torsion spring 614 is coiled around the second rod 640 below the lower cam wafer 630 . In this embodiment, an e-clip 616 is secured to the second rod 640 below the middle cam wafer 620 . Of course, in another embodiment it would be possible to have a third torsion spring coiled around the second rod 640 at the base of the middle cam wafer 620 . An alternative embodiment of the pawl arm 650 is disclosed in this view. The solenoid 660 is vertically mounted between two flanges (not shown in this view) secured to the lock box (not shown in this view). The pawl arm 650 is pivotably mounted to a fixed axis 670 on the lock box base 680 . The solenoid 660 is positioned so that the solenoid pin 664 may be attached to the frontal portion of the pawl arm 650 . In the locked position, the solenoid coil 662 remains unenergized and the frontal portion of the pawl arm 650 bends downward and engages an aperture 622 in the cam wafer 620 to secure the device. A pawl spring 690 is suspended from a flange (not shown in this view) which is secured to the distal wall of the lock box (not shown in this view). Although in the embodiment of FIG. 6 three cam wafers 610 , 620 , and 630 are secured to the second rod 640 , a plurality of cam wafers may be added to the second rod 640 for additional security. Only one solenoid 660 is necessary to power the locking mechanism, regardless of how many cam wafers 610 , 620 and 630 are added to the second rod 640 to increase the strength of the locking mechanism.
An adaptable electronic locking mechanism has thus been described. Although the foregoing description and accompanying figures discuss and illustrate specific embodiments, it should be appreciated that the present invention is to be measured only in terms of the claims that follow. | An electronic locking mechanism comprises a first rod and a second rod. The second rod secures to the first rod by a cam wafer, which is attached to the second rod. A locking and unlocking mechanism secures the cam wafer to the first rod and releases the cam wafer from the first rod via an electrical solenoid. | 8 |
[0001] This application claims the priority benefit of Taiwan patent application number 100110737 filed on Mar. 29, 2011.
FIELD OF THE INVENTION
[0002] The present invention relates to a centrifugal heat dissipation device, and more particularly to a centrifugal heat dissipation device that rotates and utilizes a produced centrifugal force to enable enhanced vapor-liquid circulation of a working fluid filled therein. The present invention also relates to a motor that uses the above-described centrifugal heat dissipation device and therefore has largely upgraded heat dissipation performance.
BACKGROUND OF THE INVENTION
[0003] All the currently available motors, power generators, and various kinds of electric engines include a rotor and a stator. When a motor is excited due to the effect of stator-rotor mutual induction, the motor works or generates power. Heat will be generated when the silicon steel sheets provided on the rotor and the winding coils wound on the silicon steel sheets are supplied with an electric current. The hysteresis loss (iron loss) and copper loss of the rotor would generate thermal power, which causes increased temperature and lowered efficiency of the motor rotor, and thereby limits the maximum power of the rotary motor.
[0004] A motor usually has an efficiency of 85%. The 15% loss of the motor would cause heat transfer among the motor windings, the motor stator and/or the motor housing. When operating under atmospheric pressure, the heat generated by the motor rotor is transferred to the motor housing mainly via convection. That is, the heat generated by the motor rotor is transferred to the motor housing with the air inside the motor as the heat transfer medium. By providing the motor rotor with radiating fins to cool the motor, the effect of heat transfer via convection can be maximized.
[0005] It is also possible to transfer part of the thermal loss power of the motor or the power generator to an external environment through heat conduction and radiation via the rotary shaft and bearings of the motor or the power generator. However, this type of heat transfer mechanism can only provide relatively small cooling effect. When a high-speed shaft and a thermal rotor operate in a high-temperature condition, the rotor must be cooled. Otherwise, the rotor rotating at high load is subject to burnout due to the thermal power generated by the hysteresis loss (iron loss) and copper loss.
[0006] The currently cooling systems available for motors and power generators are mainly designed to carry heat away from the stator. As to the rotor, it could not be effectively cooled since there has not been any effective heat dissipation means for rotor up to date.
[0007] In brief, the prior art motors or power generators have the following disadvantages: (1) the hysteresis loss and copper loss of the rotor thereof generates thermal power to result in increased rotor temperature and limited motor power; (2) heat tends to accumulate in the rotor; and (3) the rotor has low cooling performance.
SUMMARY OF THE INVENTION
[0008] A primary object of the present invention is to provide a centrifugal heat dissipation device that utilizes a centrifugal force to enable enhanced vapor-liquid circulation of a working fluid filled therein, so as to provide increased heat dissipation effect.
[0009] Another object of the present invention is to provide a motor with centrifugal heat dissipation device.
[0010] To achieve the above and other objects, the centrifugal heat dissipation device according to the present invention includes a main body having a shaft hole, a heat-absorption zone, and a heat-transfer zone. The heat-transfer zone has a radially inner side connected to the shaft hole and a radially outer side connected to the heat-absorption zone; and the shaft hole axially extends through the main body.
[0011] To achieve the above and other objects, the motor with centrifugal heat dissipation device according to an embodiment of the present invention includes at least one shaft, a centrifugal heat dissipation device, a plurality of silicon steel sheets, and a housing. The shaft internally defines a hollow space, and has a first end and an opposite second end communicating with the hollow space. The centrifugal heat dissipation device includes a main body having a shaft hole, a heat-absorption zone, and a heat-transfer zone. The heat-transfer zone has a radially inner side connected to the shaft hole and a radially outer side connected to the heat-absorption zone; and the shaft hole axially extends through the main body for receiving the shaft therein. The silicon steel sheets are externally fitted around the main body of the centrifugal heat dissipation device. The housing is internally provided with a magnetic member, which is located corresponding to but spaced from the silicon steel sheets when the centrifugal heat dissipation device and the shaft are mounted in the housing. The housing has at least one end being an open end, to which a cap is connected to close the housing.
[0012] To achieve the above and other objects, the motor with centrifugal heat dissipation device according to another embodiment of the present invention includes at least one shaft, a centrifugal heat dissipation device, at least one magnetic member, and a housing. The shaft internally defines a hollow space, and has a first end and an opposite second end communicating with the hollow space. The centrifugal heat dissipation device includes a main body having a shaft hole, a heat-absorption zone, and a heat-transfer zone. The heat-transfer zone has a radially inner side connected to the shaft hole and a radially outer side connected to the heat-absorption zone; and the shaft hole axially extends through the main body for receiving the shaft therein. The magnetic member is externally fitted around the main body of the centrifugal heat dissipation device. The housing is internally provided with a plurality of silicon steel sheets, which are located corresponding to but spaced from the magnetic member when the centrifugal heat dissipation device and the shaft are mounted in the housing. The housing has at least one end being an open end, to which a cap is connected to close the housing.
[0013] When the centrifugal heat dissipation device rotates along with the shaft of the motor, a centrifugal force is produced. The centrifugal force enables enhanced vapor-liquid circulation of a working fluid filled in the heat-absorption zone of the main body of the centrifugal heat dissipation device, so that heat generated by the operating motor is absorbed by the centrifugal heat dissipation device and transferred to the shaft for guiding out of the motor, allowing the motor to have largely upgraded heat dissipation performance.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] The structure and the technical means adopted by the present invention to achieve the above and other objects can be best understood by referring to the following detailed description of the preferred embodiments and the accompanying drawings, wherein
[0015] FIG. 1 is a perspective view of a first embodiment of a centrifugal heat dissipation device according to the present invention;
[0016] FIG. 2 is a cross sectional view of FIG. 1 ;
[0017] FIG. 3 a is a cross sectional view of a second embodiment of the centrifugal heat dissipation device according to the present invention;
[0018] FIG. 3 b is a cross sectional view of a variant of the second embodiment of the centrifugal heat dissipation device according to the present invention;
[0019] FIG. 4 is a cross sectional view of a third embodiment of the centrifugal heat dissipation device according to the present invention;
[0020] FIG. 5 is a perspective view of a fourth embodiment of the centrifugal heat dissipation device according to the present invention;
[0021] FIG. 6 is an exploded perspective view of a first embodiment of a motor with centrifugal heat dissipation device according to the present invention;
[0022] FIG. 7 is an assembled view of FIG. 6 ;
[0023] FIG. 8 is an assembled longitudinal sectional view of the motor of FIG. 6 ;
[0024] FIG. 9 is an exploded perspective view of a second embodiment of the motor with centrifugal heat dissipation device according to the present invention without showing the housing thereof;
[0025] FIG. 10 is an assembled perspective view of a third embodiment of the motor with centrifugal heat dissipation device according to the present invention without showing the housing thereof;
[0026] FIG. 11 is an assembled longitudinal sectional view of a fourth embodiment of the motor with centrifugal heat dissipation device according to the present invention;
[0027] FIG. 12 is an assembled longitudinal sectional view of a fifth embodiment of the motor with centrifugal heat dissipation device according to the present invention;
[0028] FIG. 13 is an assembled longitudinal sectional view of a sixth embodiment of the motor with centrifugal heat dissipation device according to the present invention;
[0029] FIG. 14 is an exploded perspective view of a seventh embodiment of the motor with centrifugal heat dissipation device according to the present invention;
[0030] FIG. 15 is an assembled view of FIG. 14 ;
[0031] FIG. 16 is an assembled longitudinal sectional view of the seventh embodiment of the motor with centrifugal heat dissipation device according to the present invention;
[0032] FIG. 17 is an assembled perspective view of an eighth embodiment of the motor with centrifugal heat dissipation device according to the present invention without showing the housing thereof;
[0033] FIG. 18 is an assembled perspective view of a ninth embodiment of the motor with centrifugal heat dissipation device according to the present invention without showing the housing thereof;
[0034] FIG. 19 is an assembled longitudinal sectional view of a tenth embodiment of the motor with centrifugal heat dissipation device according to the present invention;
[0035] FIG. 20 is an assembled longitudinal sectional view of an eleventh embodiment of the motor with centrifugal heat dissipation device according to the present invention; and
[0036] FIG. 21 is an assembled longitudinal sectional view of a twelfth embodiment of the motor with centrifugal heat dissipation device according to the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0037] The present invention will now be described with some preferred embodiments thereof and with reference to the accompanying drawings. For the purpose of easy to understand, elements that are the same in the preferred embodiments are denoted by the same reference numerals.
[0038] Please refer to FIGS. 1 and 2 that are assembled perspective view and cross sectional view, respectively, of a first embodiment of a centrifugal heat dissipation device 1 a according to the present invention. As shown, the centrifugal heat dissipation device 1 a in the first embodiment includes a cylindrical main body 1 having a shaft hole 11 , a heat-absorption zone 12 , and a heat-transfer zone 13 . The heat-transfer zone 13 has a radially outer side connected to the heat-absorption zone 12 and a radially inner side connected to the shaft hole 11 . The shaft hole 11 axially extends through the main body 1 .
[0039] The heat-absorption zone 12 is internally provided with a working fluid 2 .
[0040] Please refer to FIG. 3 a that is a cross sectional view of a second embodiment of the centrifugal heat dissipation device 1 a according to the present invention, and to FIG. 3 b that is a cross sectional view of a variant of the second embodiment of the centrifugal heat dissipation device 1 a . As can be seen from FIGS. 3 a and 3 b , the centrifugal heat dissipation device 1 a in the second embodiment and the variant thereof are generally structurally similar to the first embodiment, except for a wick structure 125 that is further provided in the heat-absorption zone 12 . The wick structure 125 may be a sintered powder structure as shown in FIG. 3 a , or a net-like structure as shown in FIG. 3 b , or include a plurality of continuous or discontinuous grooves (not shown), or be any combination of the previous structures.
[0041] FIG. 4 is a cross sectional view of a third embodiment of the centrifugal heat dissipation device according to the present invention. As shown, the third embodiment is generally structurally similar to the first embodiment, except for a plurality of recesses 126 formed in the heat-absorption zone 12 .
[0042] FIG. 5 is a perspective view of a fourth embodiment of the centrifugal heat dissipation device according to the present invention. The fourth embodiment is generally structurally similar to the first embodiment, except that the heat-absorption zone 12 is radially outward extended from only a partial axial length of the heat-transfer zone 13 and has a first transverse surface 12 a and an opposite second transverse surface 12 b.
[0043] The present invention also relates to a motor 9 with centrifugal heat dissipation device. Please refer to FIGS. 6 , 7 and 8 , in which a first embodiment of the motor 9 with centrifugal heat dissipation device according to the present invention is shown. As shown, the motor 9 in the first embodiment thereof includes at least one shaft 3 , a centrifugal heat dissipation device 1 a , a plurality of silicon steel sheets 4 , and a housing 5 .
[0044] The shaft 3 internally defines a hollow space 31 and has a first end 32 and an opposite second end 33 . The first and the second end 32 , 33 are communicable with the hollow space 31 .
[0045] The centrifugal heat dissipation device 1 a includes a cylindrical main body 1 , which includes a shaft hole 11 , a heat-absorption zone 12 , and a heat-transfer zone 13 . The heat-transfer zone 13 has a radially inner side connected to the shaft hole 11 and a radially outer side connected to the heat-absorption zone 12 . The shaft hole 11 axially extends through the main body 1 , and the shaft 3 is fitted in the shaft hole 11 .
[0046] The silicon steel sheets 4 are externally fitted around the main body 1 of the centrifugal heat dissipation device 1 a.
[0047] The housing 5 is internally provided with a magnetic member 51 , which is located corresponding to but spaced from the silicon steel sheets 4 when the centrifugal heat dissipation device 1 a and the shaft 3 are mounted in the housing 5 . The housing 5 has at least one end being an open end, to which a cap 52 is connected to close the housing 5 . In a preferred embodiment, the magnetic member 51 is a magnet.
[0048] A cooling fluid 6 is filled in the hollow space 31 of the shaft 3 . The cooling fluid 6 may be air, oil, or water.
[0049] The silicon steel sheets 4 have a plurality of winding coils 41 externally wound thereon.
[0050] Please refer to FIG. 9 that is an exploded perspective view of a second embodiment of the motor according to the present invention without showing the housing thereof. As shown, the motor in the second embodiment is generally structurally similar to the first embodiment, except that the centrifugal heat dissipation device for the second embodiment has a heat-absorption zone 12 that is radially outward extended from only a partial axial length of the heat-transfer zone 13 and has a first transverse surface 12 a and an opposite second transverse surface 12 b , and the silicon steel sheets 4 are in contact with the first or the second transverse surface 12 a , 12 b of the heat-absorption zone 12 of the centrifugal heat dissipation device.
[0051] FIG. 10 is an assembled perspective view of a third embodiment of the motor according to the present invention without showing the housing thereof. As shown, the motor in the third embodiment is generally structurally similar to the second embodiment, except for a first rotary oil seal 71 and a second rotary oil seal 72 that are further mounted around the first and the second end 32 , 33 of the shaft 3 , respectively.
[0052] Please refer to FIG. 11 that is an assembled longitudinal sectional view of a fourth embodiment of the motor according to the present invention. As shown, the motor in the fourth embodiment is generally structurally similar to the third embodiment, except for a pressure device 10 that is further connected to the shaft 3 . The pressure device 10 is a pump formed of a pressure unit 101 , a first pipe 102 , and a second pipe 103 . The pressure unit 101 has an outlet 1011 and an inlet 1012 , which are connected to the two ends of the shaft 3 via the first pipe 102 and the second pipe 103 , respectively.
[0053] Please refer to FIG. 12 that is an assembled longitudinal sectional view of a fifth embodiment of the motor according to the present invention. As shown, the motor in the fifth embodiment is generally structurally similar to the third embodiment, except for a pressure device 10 that is further mounted to the hollow space 31 of the shaft 3 . The pressure device 10 is a turbine blade assembly being able to guide a cooling fluid 6 (i.e. ambient air) into the hollow space 31 when the shaft 3 is rotating, so as to remove heat from the rotating shaft 3 to achieve the purpose of cooling the motor.
[0054] FIG. 13 is an assembled longitudinal sectional view of a sixth embodiment of the motor according to the present invention. As shown, the motor in the sixth embodiment is generally structurally similar to the second embodiment, except for a pressure device 10 that is further connected to one end of the shaft 3 . The pressure device 10 is a fan being able to guide a cooling fluid 6 (i.e. ambient air) into the hollow space 31 of the shaft 3 when the shaft 3 is rotating, so as to remove heat from the rotating shaft 3 to achieve the purpose of cooling the motor.
[0055] Please refer to FIGS. 14 , 15 and 16 , which are respectively an exploded perspective view, an assembled perspective views, and an assembled longitudinal sectional view of a seventh embodiment of the motor 9 with centrifugal heat dissipation device according to the present invention. As shown, the motor 9 with centrifugal heat dissipation device in the seventh embodiment thereof includes at least one shaft 3 , a centrifugal heat dissipation device 1 a , at least one magnetic member 51 , and a housing 5 .
[0056] The shaft 3 internally defines a hollow space 31 , and has a first end 32 and a second end 33 . The first and second ends 32 , 33 are communicable with the hollow space 31 .
[0057] The centrifugal heat dissipation device 1 a includes a main body 1 , which has a shaft hole 11 , a heat-absorption zone 12 , and a heat-transfer zone 13 as that shown in FIG. 1 . The heat-transfer zone 13 has a radially inner side connected to the shaft hole 11 and a radially outer side connected to the heat-absorption zone 12 . The shaft hole 11 axially extends through the main body 1 , and the shaft 3 is fitted in the shaft hole 11 .
[0058] The magnetic member 51 is externally fitted around the main body 1 of the centrifugal heat dissipation device 1 a.
[0059] The housing 5 is internally provided with a plurality of silicon steel sheets 4 , which are located corresponding to but spaced from the magnetic member 51 when the centrifugal heat dissipation device 1 a and the shaft 3 are mounted in the housing 5 . The housing 5 has at least one end being an open end, to which a cap 52 is connected to close the housing 5 . In a preferred embodiment, the magnetic member 51 is a magnet.
[0060] A cooling fluid 6 is filled in the hollow space 31 of the shaft 3 . The cooling fluid 6 may be air, oil, or water.
[0061] The silicon steel sheets 4 have a plurality of winding coils 41 externally wound thereon.
[0062] FIG. 17 is an assembled perspective view of an eighth embodiment of the motor according to the present invention without showing the housing thereof. As shown, the motor in the eighth embodiment is generally structurally similar to the seventh embodiment, except that the centrifugal heat dissipation device for the eighth embodiment has a heat-absorption zone 12 that is radially outward extended from only a partial axial length of the heat-transfer zone 13 and has a first transverse surface 12 a and an opposite second transverse surface 12 b , and the magnetic member 51 is in contact with the first or the second transverse surface 12 a , 12 b of the heat-absorption zone 12 .
[0063] FIG. 18 is an assembled perspective view of a ninth embodiment of the motor according to the present invention without showing the housing thereof. As shown, the motor in the ninth embodiment is generally structurally similar to the eighth embodiment, except for a first rotary oil seal 71 and a second rotary oil seal 72 that are further mounted around the first and the second end 32 , 33 of the shaft 3 , respectively.
[0064] Please refer to FIG. 19 that is an assembled longitudinal sectional view of a tenth embodiment of the motor according to the present invention. As shown, the motor in the tenth embodiment is generally structurally similar to the ninth embodiment, except for a pressure device 10 that is further connected to the shaft 3 . The pressure device 10 is a pump formed of a pressure unit 101 , a first pipe 102 , and a second pipe 103 . The pressure unit 101 has an outlet 1011 and an inlet 1012 , which are connected to the two ends of the shaft 3 via the first pipe 102 and the second pipe 103 , respectively.
[0065] Please refer to FIG. 20 that is an assembled longitudinal sectional view of an eleventh embodiment of the motor according to the present invention. As shown, the motor in the eleventh embodiment is generally structurally similar to the seventh embodiment, except for a pressure device 10 that is further mounted to the hollow space 31 of the shaft 3 . The pressure device 10 is a turbine blade assembly being able to guide a cooling fluid 6 (i.e. ambient air) into the hollow space 31 when the shaft 3 is rotating, so as to remove heat from the rotating shaft 3 to achieve the purpose of cooling the motor.
[0066] FIG. 21 is an assembled longitudinal sectional view of a twelfth embodiment of the motor according to the present invention. As shown, the motor in the twelfth embodiment is generally structurally similar to the ninth embodiment, except for a pressure device 10 that is further connected to one end of the shaft 3 . The pressure device 10 is a fan being able to forcedly guide a cooling fluid 6 (i.e. ambient air) into the hollow space 31 of the shaft 3 when the shaft 3 is rotating, so as to remove heat from the rotating shaft 3 to achieve the purpose of cooling the motor.
[0067] In the previous eighth to twelfth embodiments, the cooling fluid 6 filled in the hollow space 31 of the shaft 3 may also be air, oil, a refrigerant, or water.
[0068] Please refer to FIGS. 1 to 21 . According to the embodiments of the present invention, the centrifugal heat dissipation device 1 a is a thermosiphon plate. The centrifugal heat dissipation device 1 a is internally in a vacuum low-pressure state and filled with a working fluid 2 . The working fluid 2 absorbs the heat transferred to the centrifugal heat dissipation device 1 a , so that the working fluid 2 in the centrifugal heat dissipation device 1 a is vaporized or boiled. In other words, the working fluid 2 absorbs sufficient latent heat of evaporation and is transformed into a vapor-phase working fluid 21 . The vapor-phase working fluid 21 is subject to a lower radially outward centrifugal force compared to a liquid-phase working fluid 22 . The centrifugal force would guide the vapor-phase working fluid 21 toward a rotating center, i.e. toward a center of the shaft 3 , while guiding the liquid-phase working fluid 22 toward the radially outer side of the heat-absorption zone 12 to thereby achieve a vapor-liquid separating function. Therefore, the centrifugal heat dissipation device 1 a provides better heat transfer efficiency than conventional heat pipes and vapor chambers that guide the working fluid only via the force of gravity.
[0069] The present invention has been described with some preferred embodiments thereof and it is understood that many changes and modifications in the described embodiments can be carried out without departing from the scope and the spirit of the invention that is intended to be limited only by the appended claims. | A centrifugal heat dissipation device and a motor using same are disclosed. The centrifugal heat dissipation device includes a main body having a shaft hole, a heat-absorption zone and a heat-transfer zone. The heat-transfer zone has a radially outer side connected to the heat-absorption zone and a radially inner side connected to the shaft hole. The shaft hole axially extends through the main body for receiving a shaft of a motor therein. A centrifugal force generated by the rotating shaft and accordingly, the heat dissipation device enables enhanced vapor-liquid circulation of a working fluid in the heat dissipation device, so that heat generated by the operating motor is absorbed by the centrifugal heat dissipation device and transferred to the shaft for guiding out of the motor, allowing the motor to have largely upgraded heat dissipation performance. | 5 |
BACKGROUND OF THE INVENTION
Field of the invention
This invention relates to novel laundry detergent compositions having a high water-soluble alkaline carbonate builder content, the use of which results in reduced fabric encrustation.
Information Disclosure Statement Including Description of Related Art
The following information is being disclosed under the provisions of 37 CER 1.56, 1.97 and 1.98.
Laundry detergent compositions comprising a water-soluble alkaline carbonate are well-known in the art. For example, it is conventional to use such a carbonate as a builder in detergent compositions which supplement and enhance the cleaning effect of an active surfactant present in the composition. Such builders improve the cleaning power of the detergent composition, for instance, by the sequestration or precipitation of hardness causing metal ions such as calcium, peptization of soil agglomerates, reduction of the critical micelle concentration, and neutralization of acid soil, as well as by enhancing various properties of the active detergent, such as its stabilization of solid soil suspensions, solubilization of water-insoluble materials, emulsification of soil particles, and foaming and sudsing characteristics. Other mechanisms by which builders improve the cleaning power of detergent compositions are probably present but are less well understood. Builders are important not only for their effect in improving the cleaning ability of active surfactants in detergent compositions, but also because they allow for a reduction in the amount of the surfactant used in the composition, the surfactant being generally much more costly than the builder.
Two important classes of builders have been widely used in recent years, viz., phosphorus containing salts such as sodium tripolyphosphate (STPP) which are very effective in sequestering calcium and magnesium ions without precipitating them, and the water-soluble alkaline carbonates mentioned previously such as sodium carbonates which may be used in amounts up to 90 wt. % of the composition and which effectively precipitate the calcium ions. However, phosphorus-containing builders have been found to cause a serious problem of eutrophication of lakes, rivers and streams when present in detergent compositions in relatively large amounts, resulting in the passage of laws in several states mandating a drastic reduction in their use. While the use of water-soluble alkaline carbonate builders do not cause eutrophication, they result in the unrelated problem of calcium carbonate precipitation, leading to, for example, fabric encrustation due to the deposition of the calcium carbonate on the fiber surfaces of fabrics which in turn causes fabric to have a stiff hand and gives colored fabrics a faded appearance.
Polymeric polycarboxylates such as polyacrylates are also known in the detergent art as effective sequestering and dispersing agents as well as crystal growth inhibitors. However, such polycarboxylates have limited biodegradability which presents an environmental problem if they are used in relatively large amounts.
The following prior art references may be considered relevant or material to the invention claimed herein.
U.S. Pat. Nos. 4,265,790, issued May 5, 1981 to Winston et al., and 4,464,292, issued Aug. 7, 1984 to Lengyel, disclose detergent compositions comprising an ethoxylated alcohol and an ethoxy sulfate as a combination of nonionic and anionic surfactants, and over 70 wt % of anhydrous sodium carbonate (soda ash) as a detergent builder.
U.S. Pat. No. 4,490,271, issued Dec. 25, 1984 to Spadini et al., discloses detergent compositions comprising an active surfactant, up to 80% of a non-phosphorus detergent builder such as a water-soluble carbonate, and a polyacrylate such as a copolymer of acrylic acid with any of various comonomers.
U.S. Pat. No. 4,521,332, issued Jun. 4, 1985 to Milora, discloses highly alkaline liquid cleaning compositions comprising a nonionic surfactant, 10 to 45 wt. % of sodium hydroxide, 0.04 to 4 wt. % of a polyacrylic acid salt, 0 to 15 wt. % of an alkali metal phosphate builder such as STPP, 0.5 to 20 wt. % of a "building agent" such as sodium carbonate, and 6 to 60 wt. % of water.
U.S. Pat. No. 4,711,740, issued Dec. 8, 1987 to Carter et al., discloses detergent compositions comprising a "detergent active" compound, i.e., a surfactant, a detergent builder which is a water-soluble carbonate, e.g. sodium carbonate in an amount of "at least 5% by weight, such as from 10% to 40%, preferably 10% to 30% weight, though an amount up to 75% could possible be used if desired in special products," a water insoluble carbonate, e.g., calcium carbonate (calcite) in an amount of 5 to 60 wt. %, as seed crystals for precipitated calcium carbonate which is thus prevented from being deposited on fabrics; and a copolymer of a carboxylic monomer, e.g., acrylic acid, and a non-carboxylic monomer, such copolymer being present in an amount of 0.1 to 10 wt. % and acting as a colloid stabilizer for the precipitated calcium carbonate. Other detergency builders such as STPP may also be present.
U.S. Pat. No. 4,820,441, issued Apr. 11, 1989 to Evans et al., discloses granular detergent compositions which may contain in addition to an active surfactant, 5 to 75 wt. % of a crystal growth modified, carbonate-based structurant salt, 0.1 to 20 wt. % of a polymeric polycarboxylate as crystal growth modifier based on the weight of the structurant salt, and 0 to 40 wt. % of STPP. The structurant salt may contain sodium sulfate as well as sodium carbonate and sodium bicarbonate, and the two tables under the heading "PRODUCTS OF THE INVENTION" in columns 8 and 9 of the patent show a maximum of 40 wt. % of sodium carbonate in the final product composition.
U.S. Pat. No. 4,849,125, issued Jul. 18, 1989 to Seiter et al., discloses phosphate-reduced, granular, free-flowing detergent compositions comprising 4 to 40 wt. % of a nonionic surfactant, 3 to 20 wt. % of an anionic surfactant, 0.5 to 15 wt. % of a homopolymeric or copolymeric carboxylic acid or salt, 0 to 20 wt. % of STPP, and, optionally, up to 15 or 20 wt. % of sodium carbonate.
M. M. Reddy and K. K. Wang, "Crystallization of Calcium Carbonate in the Presence of Metal Ions" Journal of Crystal Growth 50 (1980) 470-480, discusses the influence of magnesium ions in solution on the growth of pure calcite from a stable supersaturated solution onto a well-characterized pure calcite surface.
Application Ser. No. 08/136,397, filed Oct. 13, 1993 by the applicants in this application, discloses and claims carbonate built cleaning compositions containing a minor amount of elemental magnesium in the form of a water soluble salt, but is not limited to laundry detergent compositions containing an active surfactant and a polymeric polycarboxylate as is this application.
SUMMARY OF THE INVENTION
In accordance with this invention a laundry detergent composition is provided wherein the solids content comprises an active surfactant, at least about 70 wt. % of a water-soluble alkaline carbonate, up to about 12 wt. %, of elemental magnesium in the form of a water soluble salt, and about 0.05 to 5 wt. % of a polymeric polycarboxylate, based on the total weight of solids in the composition. The term "polymeric polycarboxylate" includes homopolymers of monoethylenically unsaturated carboxylic acids and copolymers of such acids as hereinafter defined.
Incorporation of magnesium ions in the foregoing laundry detergent composition containing carbonate ions is intended to minimize negative interactions that will occur between the precipitation of calcium carbonate and the surfaces of the fabric being cleaned. For example, the composition is capable of providing excellent cleaning and whitening of fabrics while avoiding the problem of eutrophication which occurs when a substantial amount of a phosphorous containing builder such as STPP is present in the composition, and while minimizing the problem of fabric encrustation often present when the composition contains a large amount of carbonate builder.
The reduction in the amount of fabric encrustation when using the laundry detergent composition of this invention is apparently partly due to an effect of magnesium ions at certain concentrations in inhibiting the precipitation of calcium carbonate on the substrate being cleaned, i.e., fabric surfaces, for a limited period of time, with an enhancement of this effect due to the presence of the polymeric polycarboxylate. This is a surprising effect since magnesium is commonly considered to be equal to calcium as a hardness ingredient of water. Furthermore the enhancement in the reduction of encrustation caused by the combination of polymeric polycarboxylate with magnesium is also surprising since such polycarboxylate is conventionally used in detergent compositions to prevent encrustation by calcium and magnesium hardness.
DETAILED DESCRIPTION OF THE INVENTION
The water-soluble alkaline carbonate may be, for example, an alkali metal carbonate, bicarbonate or sesquicarbonate, preferably sodium or potassium carbonate, bicarbonate or sesquicarbonate, and most preferably sodium carbonate. A combination of more than one of such compounds may be used, e.g., sodium carbonate and sodium bicarbonate. The total water-soluble alkaline carbonate may be present in an amount, for example, of about 70 to 90 wt. %, preferably about 75 to 85 wt. %. If a combination of alkali metal carbonate and bicarbonate is used as the water-soluble carbonate, then the alkali metal carbonate, e.g., sodium carbonate, is preferably used in an amount of about 75 to 80 wt. % and the alkali metal bicarbonate, e.g., sodium bicarbonate, in an amount of about 0.1 to 15 wt. %.
Water soluble magnesium salts which may be used in preparing the detergent compositions of this invention are, for example, magnesium sulfate, magnesium chloride, magnesium nitrate, magnesium acetate, and dibasic magnesium citrate. Sufficient magnesium salt is added to the composition such that elemental magnesium is present in an amount, for example, of up to about 12 wt. % based on the total solids. In general, the wash water before the addition of cleaning composition contains a calcium hardness of for example, about 10 to 350 ppm of calcium hardness expressed as CaCO 3 and a Ca/Mg molar ratio of, for example, about 5/1 to 2/1 may be present, in which case the elemental magnesium in the detergent composition should be, for example, about 0.1 to 12 wt. %, preferably about 1 to 5 wt. % based on the weight of total solids in the composition. An amount of magnesium within the foregoing ranges may add, for example about 7 to 800 ppm, preferably about 65 to 340 ppm, of magnesium expressed as CaCO 3 to the wash water, based on the weight of the wash water, so that the final wash liquor contains after the addition of detergent composition, for example, about 15 to 1160 ppm, preferably about 75 to 690 ppm of magnesium expressed as CaCO 3 . This has the effect of decreasing the Ca/Mg molar ratio in the wash liquor by a number of units in the range of about 4/1 to 1/4 units, preferably about 1/1 to 1/2 units, so that the Ca/Mg molar ratio in the wash liquor after the addition of the detergent composition is in the range, for example, of about 4/1 to about 1/4, preferably about 1/1 to about 1/2, at which the beneficial effect of magnesium in reducing encrustation is most evident. If the calcium hardness and magnesium content of the wash water before the addition of detergent composition is known to be substantially outside the stated ranges, the broad and preferred ranges of the amount of elemental magnesium in the detergent composition may be adjusted so that the amount of calcium and magnesium in the wash liquor falls within the foregoing ranges after the addition of detergent composition. The foregoing ranges of amount of magnesium in the detergent composition and the calcium and magnesium content of the wash liquor before and after the addition of detergent composition assume normal and accepted use of a detergent wherein the wash liquor contains about 0.1 to 1 wt. % of detergent solids during the washing operation. The term "expressed as CaCO 3 " as applied to amounts of calcium or magnesium in this paragraph and hereinafter, means the weight in parts per million of the number of moles of CaCO 3 equal to the number of moles of calcium or magnesium being characterized.
The active surfactant component may be, for example, one or more of many suitable synthetic detergent active compounds which are commercially available and described in the literature, e.g., in "Surface Active Agents and Detergents", Volumes 1 and 2 by Schwartz, Perry and Berch. Several detergents and active surfactants are also described in, for example, U.S. Pat. Nos. 3,957,695; 3,865,754; 3,932,316 and 4,009,114. In general, the composition may include a synthetic anionic, nonionic, amphoteric or zwitterionic detergent active compound, or mixtures of two or more of such compounds.
More preferably, the laundry detergent compositions of this invention contain at least one anionic or nonionic surfactant, and, most preferably, a mixture of the two types of surfactant.
The contemplated water soluble anionic detergent surfactants are the alkali metal (such as sodium and potassium) salts of the higher linear alkyl benzene sulfonates and the alkali metal salts of sulfated ethoxylated and unethoxylated fatty alcohols, and ethoxylated alkyl phenols. The particular salt will be suitably selected depending upon the particular formulation and the proportions therein.
The sodium alkybenzenesulfonate surfactant (LAS), if used in the composition of the present invention, preferably has a straight chain alkyl radical of average length of about 11 to 13 carbon atoms.
Specific sulfated surfactants which can be used in the compositions of the present invention include sulfated ethoxylated and unethoxylated fatty alcohols, preferably linear primary or secondary monohydric alcohols with C 10 -C 18 , preferably C 12 -C 16 , alkyl groups and, if ethoxylated, on average about 1-15, preferably 3-12 moles of ethylene oxide (EO) per mole of alcohol, and sulfated ethoxylated alkylphenols with C 12 -C 16 alkyl groups, preferably C 8 -C 9 alkyl groups, and on average from 4-12 moles of EO per mole of alkyl phenol.
The preferred class of anionic surfactants are the sulfated ethoxylated linear alcohols, such as the C 12 -C 16 alcohols ethoxylated with an average of from about 1 to about 12 moles of ethylene oxide per mole of alcohol. A most preferred sulfated ethoxylated detergent is made by sulfating a C 12 -C 15 alcohol ethoxylated with 3 moles of ethylene oxide per mole of alcohol.
Specific nonionic surfactants which can be used in the compositions of the present invention include ethoxylated fatty alcohols, preferably linear primary or secondary monohydric alcohols with C 10 -C 18 , preferably C 12 -C 16 , alkyl groups and on average about 1-15, preferably 3-12 moles of ethylene oxide (EO) per mole of alcohol, and ethoxylated alkylphenols with C 8 -C 16 alkyl groups, preferably C 8 -C 9 alkyl groups, and on average about 4-12 moles of EO per mole of alkyl phenol.
The preferred class of nonionic surfactants are the ethoxylated linear alcohols, such as the C 12 -C 16 alcohols ethoxylated with an average of from about 1 to about 12 moles of ethylene oxide per mole of alcohol. A most preferred nonionic detergent is a C 12 -C 15 alcohol ethoxylated with 3 moles of ethylene oxide per mole of alcohol.
Mixtures of the foregoing synthetic detergent type of surfactants, e.g., of anionic and nonionic, or of different specific anionic or nonionic surfactants, may be used to modify the detergency, sudsing characteristics, and other properties of the composition. For example, a mixture of different fatty alcohols of 12 to 15 carbon atoms may be ethoxylated, directly sulfated, or sulfated after ethoxylation, a fatty alcohol may be partially ethoxylated and sulfated, or an ethoxylated fatty acid may be partially sulfated to yield a mixture of different anionic and nonionic surfactants or different specific anionic or nonionic surfactants.
The total active surfactant in the composition may be in the range, for example, of about 5 to 15 wt. % preferably about 8 to 12 wt. % based on the weight of solids in the composition. If, as preferred, the active surfactant consists of a combination of anionic and nonionic surfactants, then the anionic surfactant is present in the range, for example, of about 4 to 14 wt. %, preferably about 5 to 10 wt. %, and the nonionic surfactant is present in the range, for example, of about 2 to 8 wt. %, preferably about 3 to 5 wt. %, all based on the weight of total solids.
The polymeric polycarboxylate may be, for example, a homopolymer or copolymer (composed of two or more co-monomers) of an alpha, beta-ethylenically unsaturated acid monomer such as acrylic acid, methacrylic acid, a diacid such as maleic acid, itaconic acid, fumaric acid, mesoconic acid, citraconic acid and the like, a monoester of a diacid with an alkanol, e.g., having 1-8 carbon atoms, and mixtures thereof. When the polymeric polycarboxylate is a copolymer, it may be a copolymer of more than one of the foregoing unsaturated acid monomers, e.g., acrylic acid and maleic acid, or a copolymer of at least one of such unsaturated acid monomers with at least one non-carboxylic alpha, beta-ethylenically unsaturated monomer which may be either relatively non-polar such as styrene or an olefinic monomer, such as ethylene, propylene or butene-1, or which has a polar functional group such as vinyl acetate, vinyl chloride, vinyl alcohol, alkyl acrylates, vinyl pyridine, vinyl pyrrolidone, or an amide of one of the delineated unsaturated acid monomers, such as acrylamide or methacrylamide. Certain of the foregoing copolymers may be prepared by aftertreating a homopolymer or a different copolymer, e.g., copolymers of acrylic acid and acrylamide by partially hydrolyzing a polyacrylamide.
Copolymers of at least one unsaturated carboxylic acid monomer with at least one non-carboxylic comonomer should contain at least about 50 mol % of polymerized carboxylic acid monomer.
The polymeric polycarboxylate should have a number average molecular weight of, for example about 1000 to 10,000, preferably about 2000 to 5000. To ensure substantial water solubility, the polymeric polycarboxylate is completely or partially neutralized, e.g., with alkali metal ions, preferably sodium ions, or with magnesium ions supplied by magnesium oxide or hydroxide which thus acts as the source of the added magnesium.
The polymeric polycarboxylate is present in the detergent composition in an amount, for example, of about 0.05 to 5 wt. % preferably about 0.1 to 2 wt. % based on the weight of the total solids.
In addition to its usual function as a soil antiredeposition agent, the polymeric polycarboxylate has the unexpected effect in this invention of enhancing the reduction of encrustation caused by the added magnesium. Thus, in the absence of polymeric polycarboxylate, the added magnesium of this invention has the effect of reducing fabric encrustation for wash cycle times of up to about 12 minutes when the total calcium plus magnesium hardness of the wash water is at least about 50 ppm expressed as CaCO 3 ; at wash cycle times appreciably above about 20 minutes, the addition of magnesium may increase encrustation. However, in the presence of a polymeric polycarboxylate, the addition of magnesium reduces encrustation at all practical wash cycle times and to a degree considerably greater than the added magnesium alone, or of the polymeric polycarboxylate alone.
The detergent composition of this invention is preferably in the form of a dry-appearing powder, in which case the weight percentages of the various components mentioned previously are approximately based on the weight of the total composition. However, such dry appearing powder generally contains water in an amount, for example, of about 1 to 12 wt. %, preferably about 2 to 10 wt. % based on the weight of the total composition. Alternatively, however, the detergent composition may be in the form of a liquid, e.g., a concentrated aqueous solution of the detergent components containing, for example, about 0.5 to 30 wt. % of detergent solids.
The laundry detergent compositions of this invention may also contain various adjuvants common to detergent formulations such as brighteners, enzymes, carboxymethylcellulose, perfumes, dyes and peroxide generating persalts.
The following examples further illustrate the invention. In the examples involving values of turbidity, a test for turbidity was used, the results of which correlate with the fabric encrustation caused by the employment of a carbonate built detergent composition, with lower turbidity indicating lower fabric encrustation. The test is carried out utilizing a calcium hardness solution containing a predetermined amount of calcium chloride dihydrate dissolved in deionized water, and a detergent solution in deionized water of a predetermined amount of carbonate built detergent composition to be tested containing either no magnesium as a control or a predetermined amount of a soluble magnesium salt such as magnesium sulfate or magnesium chloride. The concentrations of calcium chloride dihydrate in the calcium hardness solution and of the components of the detergent composition are controlled so that when predetermined amounts of the two solutions are mixed together with a predetermined additional amount of ionized water, an overall solution containing about 0.162 wt. % of detergent composition, a desired calcium hardness expressed as ppm of calcium carbonate, and a desired amount of magnesium as ppm of CaCO 3 and level of Ca/Mg molar ratio are obtained. The predetermined amounts of the two solutions and the deionized water to be added, are preheated to 35° C. and combined with stirring simultaneously with the starting of a timer. Stirring of the combined solution is continued and the turbidity of the solution is measured with a Hach Turbidimeter in National Turbidity Units (NTU's) at certain set time intervals, e.g., 5, 10, 15 and 20 min.
Example 1 and Comparative Examples A, B and C
In each of these examples, turbidity determinations were carried out using solutions of a base detergent composition comprising 80 parts of sodium carbonate, 0.5 parts of sodium bicarbonate, an active surfactant consisting of 6.0 parts of the sodium salt of a sulfated C 12 -C 15 alcohol (anionic surfactant) and 3.2 parts of a C 12 -C 15 alcohol ethoxylated with 3 moles of ethylene oxide per mole of alcohol (nonionic surfactant) and a calcium hardness in the combined solution of 100 ppm expressed as CaCO 3 . However, the examples differed in that no magnesium was present in the combined solution in Comparative Examples A and C, 100 ppm of magnesium expressed as CaCO 3 was present in Comparative Example B and Example 1 such that the Ca/Mg molar ratio was 1/1, no polymeric polycarboxylate ("polymer") was present in Comparative Examples A and B and 1.5 wt. % of a polymer based on the weight of the detergent composition was present in Comparative Example C and Example 1, such polymer being a terpolymer of about 49.5 wt. % acrylic acid, about 49.5 wt. % maleic acid, and about 1 wt. % of acrylamide and having a number average molecular weight of about 3000. The polymer was completely neutralized on contact with the sodium carbonate of the detergent formulation. The turbidities after 10 and 20 min. are shown in Table I.
TABLE I______________________________________ Polymer Mg, Turbidity (NTU)Example wt. % ppm as CACO.sub.3 10 min. 20 min.______________________________________A 0 0 113 118B 0 100 9 77C 1.5 0 30 311 1.5 100 0.4 0.5______________________________________
The results of Table I show that not only do magnesium and the polymeric polycarboxylate each separately reduce turbidity substantially after 10 and 20 min., but that the presence of both magnesium and polymeric polycarboxylate reduce the turbidity still further to a degree which could not have been predicted from the separate effects of the magnesium and polymer, i.e., the two additives together result in a synergistic effect.
Example 2 and Comparative Example D
In Comparative Example D, the procedure of Comparative Example B was followed utilizing 150 ppm of calcium and varying amounts of magnesium. The results are shown in Table II.
TABLE II______________________________________Mg present, Ca/Mg Turbidity (NTU)ppm as CaCO.sub.3 molar ratio 10 min 20 min______________________________________ 0 -- 192 -- 50 3/1 157 176 75 2/1 159 172100 1.5/1 128 170125 1.2/1 26 138150 1/1 31 69175 1.5/1.75 20 109200 1.5/2 86 177______________________________________
The results of Table II show that at 150 ppm of Ca, the turbidity is decreased by the presence of 50 to 200 ppm of Mg corresponding to a Ca/Mg ratio of from above 3/1 to 1.5/2 after 10 min. of contact between the calcium hardness solution and the detergent solution, while after 20 min. of contact, the turbidity is decreased at a Ca/Mg ratio of from 3/1 to 1.5/1.75.
In Example 2, the procedure of Comparative Example D was followed except that 1.5 wt. % of the polymer utilized in Example 1 was present in each combined solution. The results are shown in Table III.
TABLE III______________________________________Mg, ppm Ca/Mg, Turbidity (NTU)(as CaCO3) Molar Ratio 10 min. 20 min.______________________________________ 0 -- 182 193 50 3/1 193 205 75 2/1 93 117100 1.5/1 1 22125 1.2/1 4 3150 1.0/1 9 8175 1/1.2 14 15200 1/1.3 20 24______________________________________
The results of Table III as compared with those of Table II indicate that the presence of both magnesium and polymer exerts a strong synergistic effect on the reduction of turbidity caused by the interaction of calcium hardness and a carbonate built detergent composition at 10 and 20 min. contact time.
Example 3 and Comparative Example E
These examples show the comparative results of encrustation tests of two detergent formulations. In Comparative Example E the formulation consisted of the base detergent composition described in Comparative Example A plus 1.35 wt. % of Rohm & Haas 445 polymer, which is a polyacrylic acid having a number average molecular weight of about 4500. The polymer becomes completely neutralized on contact with the sodium carbonate of the formulation. In Example 3 the formulation consisted of the same base detergent composition and polymer as Comparative Example E plus 7 wt. % of MgSO 4 . The two detergent compositions were tested for fabric encrustation by repeated washing of cotton fabric at 35° C. In carrying out the test, four 25.4 cm.×25.4 cm., 100% black cotton fabric swatches along with 0.907 kg. of ballast are washed for 12 min. with 113.4g of the detergent composition being tested such that the wash liquor contained about 0.162 wt. % of detergent. After washing is completed, 2.00-4.00 g of the calcium carbonate encrusted fabrics are extracted in 100 ml. of 0.2 N hydrochloric acid for 30 min. and a 2.0-4.0 ml. aliquot is analyzed for hardness by the EDTA titration method. Encrustation is expressed as mg. calcium carbonate per gram of fabric.
In Comparative Example E wherein the detergent formulation contained 1.35 wt. % of polymer and no magnesium, the encrustation was 53 mg of CaCO 3 per gram of fabric, while in Example 3 wherein the formulation contained 7 wt. % of MgSO 4 and 1.35 wt. % of polymer, the fabric encrustation was 15 mg CaCO 3 per gram of fabric. The latter value indicates a synergistic effect of magnesium and polymer used together since the difference between such value and that of 103 obtained when neither magnesium nor polymer was present in the formulation (Comparative Example C of Application Ser. No. 08/136,397, filed , Oct. 13, 1993) is greater than would be predicted from the value of 99 obtained when magnesium but no polymer was present in the formulation (Example 7 of Ser. No. 08/136,397), and the value of 53 obtained when polymer but no magnesium was present (Comparative Example E). The foregoing values of encrustation were obtained after five machine cycles of use.
Examples 4 to 7 and Comparative Example F
These examples illustrate that the benefit in reduced turbidity of including both magnesium and a polymeric polycarboxylate in a carbonate built detergent can be obtained by using a basic magnesium compound to neutralize the acid as well as by separate addition of a magnesium compound and polymer.
The procedure of Example 3 was followed except that the detergent formulation included 1.35 wt. % of the Rohm & Haas 445 polymer as described in Example 3, neutralized as specified hereinafter. The combined solution measured for turbidity contained, exclusive of any magnesium used to neutralize the polymer or added as equivalent to the neutralized base, 150 ppm of calcium and 75 ppm of magnesium each expressed as CaCO 3 (Ca/Mg molar ratio=2/1) which is typical of the natural hardness of water.
In Comparation Example F, the polymer was neutralized with sodium carbonate.
In Example 4, the polymer was neutralized neat with MgO.
In Example 5, the polymer was diluted with water and neutralized with MgO.
In Example 6, the polymer was neutralized with NaOH followed by "ion exchange" with a stoichiometric amount of MgSO 4 .
In Example 7, the polymer was neutralized with sodium carbonate and an equivalent amount of MgSO 4 added to the system. The turbidities of the sample after 5, 10 and 15 minutes are shown in Table IV.
TABLE IV______________________________________ Turbidity (NTU)Example 5 min. 10 min. 15 min.______________________________________F 3 40 854 4 14 485 3 5 586 1 2 557 1 1 27______________________________________
The results of Table IV indicate that at a contact time between detergent composition and wash water above a point between five and ten minutes, the turbidity is reduced by the presence of magnesium ions whether added for the neutralization of the polymer (Examples 4, 5 and 6) or separately (Example 7). The reduction in turbidity at 10 and 15 minutes in Examples 4 to 7 is obtained despite the fact that the addition of magnesium resulted in a relatively slight increase of magnesium in the combined solution, i.e., only 15 ppm expressed as CaCO 3 , for a reduction of the Ca/Mg molar ratio of from 150/75 (2/1) to 150/90.
Examples 8 to 17 and Comparative Examples G and H
These examples illustrate the effect of carrying out 5 cycle encrustation tests using varying amounts of Rohm and Haas 445 polymer and magnesium sulfate in the detergent composition at a constant hardness of wash water.
The tests were carried out using the procedure described in Example 3 and Comparative Example E, under the following constant conditions: total wash water hardness (Ca+Mg, Ca/Mg molar ratio of 2/1)=250 ppm; wash temperature=35° C.; and wash cycle=12 min. The content of Rohm and Haas 445 polymer ("polymer") and magnesium sulfate ("MgSO 4 ") as weight percent of the detergent composition and fabric encrustation as mg. of calcium carbonate per gram of fabric obtained in each example are shown in Table V.
TABLE V______________________________________ Fabric Polymer, MgSO.sub.4, Encrustation,Example wt. % wt. % mg CaCO.sub.3 /g fabric______________________________________G 0 0 97H 1.00 0 85 8 0 7 99 9 1.00 7 2810 1.00 3.5 7311 1.00 2.0 8912 1.35 7 2613 1.35 5 4314 1.35 3 5715 0.92 7 2316 0.62 7 2017 0.31 7 32______________________________________
The results of Table V indicate that at a wash cycle time of 12 min. and a polymer content of 1.00 wt. % the synergistic effect of magnesium and polymer on fabric encrustation is most pronounced when the MgSO 4 content is at least about 3.5 wt. % and increases as the MgSO 4 content is increased. However, at a MgSO 4 content of 7 wt. %, a pronounced synergistic effect can be obtained with a relatively low polymer content, e.g. 0.3 wt. % which is comparable to that obtained at a polymer content of 1.35 wt. %. | A laundry detergent composition, wherein the solids content comprises an active surfactant, at least about 70 wt. % of a water soluble alkaline carbonate, e.g., sodium carbonate, up to about 12 wt. % of elemental magnesium in the form of a water soluble salt, e.g., magnesium sulfate or magnesium chloride, and about 0.05 to 5 wt. % of a polymeric polycarboxylate, e.g., an acrylic acid polymer, based on the total weight of solids in the composition. Incorporation of magnesium ions in the foregoing laundry detergent composition containing carbonate ions is intended to minimize negative interactions that will occur between the precipitation of calcium carbonate and the surfaces of the fabric being cleaned, e.g., fabric encrustation, with an enhancement of this effect due to the presence of the polymeric polycarboxylate. | 2 |
CROSS-REFERENCE TO RELATED APPLICATION(S)
[0001] This application is a U.S. National Stage application under 35 U.S.C. §371 of an International application filed on Feb. 27, 2015 and assigned application number PCT/KR2015/001939, which claimed the benefit of a Korean patent application filed on Feb. 28, 2014 in the Korean Intellectual Property Office and assigned Serial number 10-2014-0024409, the entire disclosure of which is hereby incorporated by reference.
TECHNICAL FIELD
[0002] The present invention relates to a method and apparatus for beam coverage extension when wireless communication is performed by using a millimeter-wave band.
BACKGROUND ART
[0003] To meet the demand for wireless data traffic having increased since deployment of 4th generation (4G) communication systems, efforts have been made to develop an improved 5 th generation (5G) or pre-5G communication system. Therefore, the 5G or pre-5G communication system is also called a ‘Beyond 4G Network’ or a ‘Post LTE System’.
[0004] The 5G communication system is considered to be implemented in higher frequency (mmWave) bands, e.g., 60 GHz bands, so as to accomplish higher data rates. To decrease propagation loss of the radio waves and increase the transmission distance, the beamforming, massive multiple-input multiple-output (MIMO), Full Dimensional MIMO (FD-MIMO), array antenna, an analog beam forming, large scale antenna techniques are discussed in 5G communication systems.
[0005] In addition, in 5G communication systems, development for system network improvement is under way based on advanced small cells, cloud Radio Access Networks (RANs), ultra-dense networks, device-to-device (D2D) communication, wireless backhaul, moving network, cooperative communication, Coordinated Multi-Points (CoMP), reception-end interference cancellation and the like.
[0006] In the 5G system, Hybrid FSK and QAM Modulation (FQAM) and sliding window superposition coding (SWSC) as an advanced coding modulation (ACM), and filter bank multi carrier (FBMC), non-orthogonal multiple access (NOMA), and sparse code multiple access (SCMA) as an advanced access technology have been developed.
[0007] Communication may be interrupted by an obstacle in a millimeter-wave frequency band due to linearity of propagation. Therefore, a Line-Of-Sight (LOS) environment needs to be always maintained, or a beamforming function is necessarily required for smooth communication in a non-LOS environment. Further, beam coverage needs to be expanded in an antenna of the millimeter-wave band since the antenna has directivity instead of omni-directional radiation.
[0008] Therefore, there is a need for a low-power and small-size Radio Frequency (RF) transceiver including the beamforming function in the millimeter-wave frequency band.
DETAILED DESCRIPTION OF THE INVENTION
Technical Problem
[0009] Accordingly, an object of the present invention is to provide a method and apparatus for expanding beam coverage in a wireless communication system.
[0010] Another object of the present invention is to provide a method and apparatus for controlling a beamforming direction in a wireless communication system.
[0011] Another object of the present invention is to provide a method and apparatus for minimizing a signal loss when a beamforming direction is controlled in a wireless communication system.
[0012] Another object of the present invention is to provide a method and apparatus for simultaneously controlling a phase shifter and a switch for selecting an antenna element so as to overcome a unique propagation characteristic such as linearity, narrow beam coverage, or the like of a millimeter-wave and so as to expand beam coverage for allowing high-speed communication by using a millimeter-wave band.
[0013] Another object of the present invention is to provide a method and apparatus for decreasing a package size for a transceiver by using a direct conversion structure not requiring an Intermediate Frequency (IF) end and by implementing it in a form of a transceiver in which a transmitter and a receiver are integrated.
Technical Solution
[0014] An electronic device in a wireless communication system is provided. The device includes a plurality of antenna sets consisting of a combination of a plurality of antenna elements, a plurality of switches for selecting the plurality of antenna elements, a radio frequency (RF) transceiver including a plurality of phase shifters for shifting a phase of a signal transmitted/received through the plurality of antenna elements, and a controller for determining a beamforming direction and the phase of the signal by simultaneously controlling the plurality of switches and the plurality of phase shifters.
[0015] A method of operating an electronic device in a wireless communication system is provided. The method includes determining a beam training area, determining a beam index corresponding to the beam training area, determining a plurality of antenna elements and a plurality of phase shifters according to the determined beam index, and selecting a best beam by measuring quality of a beam based on a shifted phase and the determined antenna element.
[0016] In various exemplary embodiments, the method further includes, before determining the beam training area, measuring link quality, and examining whether the link quality satisfies a Quality of Service (QoS).
[0017] In various exemplary embodiments, the plurality of antenna sets and the plurality of antenna elements are integrated on a multi-layer substrate.
[0018] In various exemplary embodiments, the multi-layer substrate has sections A, B, and C configured in a row.
[0019] In various exemplary embodiments, the plurality of antenna sets and the plurality of antenna elements include at least one of a broadside antenna and an end-fire antenna.
[0020] In various exemplary embodiments, the plurality of antenna sets and the plurality of antenna elements include a plurality of broadside antennas.
[0021] In various exemplary embodiments, the plurality of antenna sets and the plurality of antenna elements include a plurality of end-fire antennas.
[0022] In various exemplary embodiments, the broadside antenna consists of at least one layer in the section A.
[0023] In various exemplary embodiments, the broadside antenna consists of at least one layer in the section B.
[0024] In various exemplary embodiments, the broadside antenna consists of at least one layer in the section C.
[0025] In various exemplary embodiments, the end-fire antenna is located in the section A.
[0026] In various exemplary embodiments, the end-fire antenna is located in the section B.
[0027] In various exemplary embodiments, the end-fire antenna is located in the section C.
[0028] In various exemplary embodiments, the beam book includes at least one of the beam index, switch information for the beam index, and phase information.
[0029] A wireless communication device is provided. The wireless communication device includes: at least two switches for selecting at least two of a plurality of antenna elements;
[0030] a plurality of phase shifters electrically coupled to the at least two switches to shift a phase of an RF signal; and
[0031] a controller for controlling the two or more switches and the plurality of phase shifters according to a beamforming direction of the RF signal.
Advantageous Effects
[0032] The present invention simultaneously controls a phase shifter and a switch by using a beam book, thereby having an advantage in that a communication interruption and a signal loss can be decreased in a millimeter-wave band high-speed communication system.
BRIEF DESCRIPTION OF THE DRAWINGS
[0033] FIG. 1 is a block diagram of a Radio Frequency (RF) transceiver according to an exemplary embodiment of the present invention;
[0034] FIG. 2 is a first diagram illustrating a structure of an RF transceiver according to an exemplary embodiment of the present invention;
[0035] FIG. 3 is a second diagram illustrating a structure of an RF transceiver according to an exemplary embodiment of the present invention;
[0036] FIG. 4 is a third diagram illustrating a structure of an RF transceiver according to an exemplary embodiment of the present invention;
[0037] FIG. 5 is a fourth diagram illustrating a structure of an RF transceiver according to an exemplary embodiment of the present invention;
[0038] FIG. 6 is a fifth diagram illustrating a structure of an RF transceiver according to an exemplary embodiment of the present invention;
[0039] FIG. 7 is a sixth diagram illustrating a structure of an RF transceiver according to an exemplary embodiment of the present invention;
[0040] FIG. 8 is a seventh diagram illustrating a structure of an RF transceiver according to an exemplary embodiment of the present invention;
[0041] FIG. 9 is en eighth diagram illustrating a structure of an RF transceiver according to an exemplary embodiment of the present invention;
[0042] FIG. 10 is a ninth diagram illustrating a structure of an RF transceiver according to an exemplary embodiment of the present invention;
[0043] FIG. 11 is a tenth diagram illustrating a structure of an RF transceiver according to an exemplary embodiment of the present invention;
[0044] FIG. 12 is an eleventh diagram illustrating a structure of an RF transceiver according to an exemplary embodiment of the present invention;
[0045] FIG. 13 is a flowchart illustrating a process of operating an RF transceiver according to an exemplary embodiment of the present invention; and
[0046] FIG. 14 is a block diagram of an electronic device according to an exemplary embodiment of the present invention.
MODE FOR CARRYING OUT THE INVENTION
[0047] Exemplary embodiments of the present invention will be described herein below with reference to the accompanying drawings. Further, in the following description of the present invention, well-known functions or constructions are not described in detail since they would obscure the invention in unnecessary detail. Also, the terms used herein are defined according to the functions of the present invention, and thus may vary depending on user's or operator's intention and usage. Therefore, the definition of the terms used herein must be understood based on the descriptions made herein.
[0048] Hereinafter, a method and apparatus for expanding beam coverage in a wireless communication system will be described.
[0049] The present invention relates to a technique for communicating large-volume data of at least several Gbps by using a millimeter-wave band. Communication may be interrupted by an obstacle in a millimeter-wave frequency band due to linearity of propagation. Therefore, a Line-Of-Sight (LOS) environment needs to be always maintained, or a beamforming function is necessarily required for smooth communication in a non-LOS environment. Further, beam coverage needs to be expanded in an antenna of the millimeter-wave band since the antenna has directivity instead of omni-directional radiation.
[0050] Accordingly, the present invention describes a method of overcoming linearity and narrow beam coverage as a unique propagation characteristic of a millimeter-wave, and a structure thereof.
[0051] FIG. 1 is a block diagram of an RF transceiver according to an exemplary embodiment of the present invention.
[0052] Referring to FIG. 1 , the RF transceiver of the present invention performs a beamforming function to overcome linearity of a millimeter-wave. The beamforming function including an RF phase shift function using an RF phase shifter may be implemented by using various methods such as a Local Oscillator (LO) phase shift method, an analog/baseband phase shift method, or the like. A controller controls the phase shifter to enable high speed beamforming.
[0053] For beam coverage expansion, the RF transceiver of the present invention consists of a plurality of M antenna sets 101 - 1 to 101 -M. Each antenna set may have a structure of a broadside antenna or an end-fire antenna, and the two structures may be combined. The broadside antenna set may output a beam in an up or down direction with respect to a flat surface. The end-fire antenna set may output the beam in a north, south, east, or west direction with respect to the flat surface. The antenna set having the mixed structure of the broadside antenna and the end-fire antenna may form a beam in a different direction other than the up, down, north, south, east, and west directions with respect to the flat surface.
[0054] According to a switching operation of switches 151 - 1 to 151 -N under the control of an RF controller 159 , N antenna elements are selected from M×N antenna elements constituting the M antenna sets 101 - 1 to 101 -M. Herein, the switches 151 - 1 to 151 -N represent a Multi Pole Double Throw (MPDT) switch.
[0055] In this case, the RF controller 159 constitutes a beam book and thus simultaneously controls the switches 151 - 1 to 151 -N for selecting the antenna element and phase shifters 156 - 1 to 156 -N and 157 - 1 to 157 -N for controlling an Antenna Weight Vector (AWV) to allow high-speed beamforming.
[0056] That is, the present invention can perform a beamforming function in which the RF controller 159 controls the phase shifters 156 - 1 to 156 -N and 157 - 1 to 157 -N to change a beam angle. The M antenna sets 101 - 1 to 101 -M consisting of N elements are used to expand antenna beam coverage.
[0057] The M antenna sets 101 - 1 to 101 -M consisting of the N antenna elements consist of M broadside antenna sets, M end-fire antenna sets, or M antenna sets in which the broadside antenna and the end-fie antenna are mixed.
[0058] The RF controller 159 uses the beam book to select N elements from M×N antenna elements by using a switch for selecting N antenna elements. In this case, Power Amplifiers (PAs) 154 - 1 to 154 -N perform an amplification function for transmission, and Low Noise Amplifiers (LNAs) 153 - 1 to 153 -N perform low-noise amplification for a reception signal. Further, an RF/analog block 158 may perform an analog-digital conversion process for a transmission/reception signal.
[0059] In addition, the RF controller 159 allows high-speed beam forming in such a manner that the switches 151 - 1 to 151 -N for selecting the antenna elements and the phase shifters 156 - 1 to 156 -N and 157 - 1 to 157 -N for controlling an antenna weight vector are simultaneously controlled by using the beam book under the control of a main controller 165 .
[0060] The main controller 165 may control the RF controller 159 to indicate whether to perform the beamforming function. Further, the main controller 165 may provide a beam index to the RF controller 159 .
[0061] A modem 160 performs a conversion function between a baseband signal and a bit-stream according to a physical layer protocol of a system. For example, in data transmission, the modem 160 generates complex symbols by coding and modulating a transmission bit-stream. Further, in data reception, the modem 160 restores a reception bit-stream by demodulating and decoding the baseband signal provided from a beamforming transceiver 150 .
[0062] The modem 160 and the beamforming transceiver 150 transmit and receive a signal as described above. Accordingly, the modem 160 and the beamforming transceiver 150 may be referred to as a transmitter, a receiver, a transceiver, or a communication unit. Further, the beam book is as shown in Table 1 below.
[0000]
TABLE 1
Beam Index
Switch control
Phase shifter control
0
SW[0]
SW[1]
. . .
SW[I]
PS[0]
PS[1]
. . .
PS[J]
1
SW[0]
SW[1]
. . .
SW[I]
PS[0]
PS[1]
. . .
PS[J]
Z
SW[0]
SW[1]
. . .
SW[I]
PS[0]
PS[1]
. . .
PS[J]
[0063] In Table 1 above, the RF controller 159 controls a switch and a phase shifter for a determined beam direction according to the control and provided information of the main controller 165 . That is, the main controller 165 determines the beam direction, and provides a beam index for the determined beam direction to the RF controller 159 .
[0064] Thereafter, according to the beam index included in the beam book, the RF controller 159 turns the switch on, and regulates the phase shifter. In Table 1 above, SW[ 0 ], SW[ 1 ], . . . , SW[I] correspond to the number of bits of N switches. PS[ 0 ], PS[ 1 ], . . . , PS[J] denote the number of bits of N phase shifters, and indicate that the switch and the phase shifter are simultaneously controlled according to the beam index.
[0065] FIG. 2 is a first diagram illustrating a structure of an RF transceiver according to an exemplary embodiment of the present invention.
[0066] Referring to FIG. 2 , a multi-layer substrate of the RF transceiver is divided into three sections, i.e., sections A, B, and C. For example, it is shown in FIG. 2 that an antenna set in which a broadside antenna and an end-fire antenna are mixed is located at a top plane of the section A.
[0067] An RF signal is delivered through an antenna, the RF transceiver, and a via and a signal line of the multi-layer substrate. Although the RF signal may be located in all of the sections A, B, and C, it is located at the section B for example in FIG. 2 . Further, although the RF transceiver may be located at all of the sections A, B, and C, it is located at a bottom plane in the section C for example in FIG. 2 . Each section may consist of at least one layer.
[0068] FIG. 3 is a second diagram illustrating a structure of an RF transceiver according to an exemplary embodiment of the present invention.
[0069] Referring to FIG. 3 , the diagram of FIG. 2 is viewed from an upper portion and a lower portion. It is illustrated that a broadside antenna is directed to an upper portion and an end-fire antenna is directed to a lateral portion, and the RF transceiver is located at a lower portion of a multi-layer substrate. Each section may consist of at least one layer.
[0070] FIG. 4 is a third diagram illustrating a structure of an RF transceiver according to an exemplary embodiment of the present invention.
[0071] Referring to FIG. 4 , among antennas, radiation directions of a broadside antenna and an end-fire antenna are illustrated.
[0072] The broadside antenna set radiates in an upper direction 401 , and the end-fire antenna set radiates in lateral directions 402 , 403 , 404 , and 405 .
[0073] For example, in the present invention, N antenna elements located respectively in the directions 401 , 402 , 403 , 404 , and 405 indicate one antenna set among M antenna sets.
[0074] In implementations, RF signals radiated in the respective directions 401 , 402 , 403 , 404 , and 405 may be output as a vertical polarization or a horizontal polarization according to a wireless environment.
[0075] FIG. 5 is a fourth diagram illustrating a structure of an RF transceiver according to an exemplary embodiment of the present invention.
[0076] Referring to FIG. 5 , it is illustrated that a broadside antenna is located in a section A as one or more layers, and an end-fire antenna is also located in the section A. In FIG. 5 , a parasitic patch is located in a top plane of the section A. The broadside antenna and the end-fire antenna are both located in the section A. As described above, each section may consist of at least one layer.
[0077] FIG. 6 is a fifth diagram illustrating a structure of an RF transceiver according to an exemplary embodiment of the present invention.
[0078] Referring to FIG. 6 , it is illustrated that a broadside antenna is located in a section A as one or more layers, and an end-fire antenna is located in a top plane of the section A. The broadside antenna and the end-fire antenna are both located in the section A, and a parasitic patch is located in the top plane of the section A. As described above, each section may consist of at least one layer.
[0079] FIG. 7 is a sixth diagram illustrating a structure of an RF transceiver according to an exemplary embodiment of the present invention.
[0080] Referring to FIG. 7 , it is illustrated that a broadside antenna is located in a top plane of a section A, and an end-fire antenna is located in a section B. As described above, each section may consist of at least one layer.
[0081] FIG. 8 is a seventh diagram illustrating a structure of an RF transceiver according to an exemplary embodiment of the present invention.
[0082] Referring to FIG. 8 , it is illustrated that a broadside antenna is located in a section A, and an end-fire antenna is located in a top plane of a section C for example although it can be located in any layer in the section C consisting of at least one layer. As described above, each section may consist of at least one layer.
[0083] FIG. 9 is an eighth diagram illustrating a structure of an RF transceiver according to an exemplary embodiment of the present invention.
[0084] Referring to FIG. 9 , it is illustrated that a broadside antenna is located in a top plane of a section A, and an end-fire antenna is located in a bottom plane of a section C for example although it can be located in any layer in the section C consisting of at least one layer. As described above, each section may consist of at least one layer.
[0085] FIG. 10 is a ninth diagram illustrating a structure of an RF transceiver according to an exemplary embodiment of the present invention.
[0086] Referring to FIG. 10 , it is illustrated a structure in which a broadside antenna and an end-fire antenna are mixed. Two types of antennas may be located in three sections such as sections A, B, and C of a multi-layer substrate. As described above, each section may consist of at least one layer.
[0087] FIG. 11 is a tenth diagram illustrating a structure of an RF transceiver according to an exemplary embodiment of the present invention.
[0088] Referring to FIG. 11 , it is illustrated a case of consisting of only a broadside antenna. The broadside antenna may be located in any sections such as sections A, B, and C. As described above, each section may consist of at least one layer.
[0089] FIG. 12 is an eleventh diagram illustrating a structure of an RF transceiver according to an exemplary embodiment of the present invention.
[0090] Referring to FIG. 12 , it is illustrated a case where an antenna set consists of only an end-fire antenna. The end-fire antenna may be located in any section such as sections A, B, and C. As described above, each section may consist of at least one layer.
[0091] FIG. 13 is a flowchart illustrating a process of operating an RF transceiver according to an exemplary embodiment of the present invention.
[0092] Referring to FIG. 13 , the main controller 165 of the modem of the present invention or a beam management program 1414 to be described below monitors current uplink and/or downlink quality (step 1305 ).
[0093] Thereafter, the main controller 165 or the beam management program 1414 examines whether the monitored uplink or downlink quality satisfies a pre-set Quality of Service (QoS) (step 1310 ).
[0094] If the monitored uplink or downlink quality satisfies the pre-set QoS, the main controller 165 or the beam management program 1414 ends an algorithm of the present invention.
[0095] If the monitored uplink or downlink quality does not satisfy the pre-set QoS, the main controller 165 or the beam management program 1411 sets a beam training area and determines a beam index for the set beam training area (step 1315 ).
[0096] Thereafter, the main controller 165 or the beam management program 1414 provides the beam index to the RF controller 159 of the beamforming transceiver so that a phase shifter and an MPDT switch for selecting an antenna element can be simultaneously controlled (step S 1320 ).
[0097] The RF controller 159 controls the beamforming switch and the phase shifter according to the beam index so that the electronic device can transmit or receive a beam by selecting an antenna set and a phase according to the determined beamforming direction (step 1325 ).
[0098] Thereafter, the controller 165 or the beam management program 1414 measures channel quality for the received beam, and selects a best beam (step 1330 ).
[0099] Thereafter, the main controller 165 or the beam management program 1414 examines whether the selected best beam satisfies the QoS (step 1310 ), and repeats the subsequent operations.
[0100] FIG. 14 is a block diagram of an electronic device according to an exemplary embodiment of the present invention.
[0101] Referring to FIG. 14 , the electronic device includes a memory 1410 , a processor unit 1420 , an input/output controller 1440 , a display unit 1450 , and an input device 1460 . Herein, the memory 1410 may be plural in number. Each constitutional element is described as follows.
[0102] The memory 1410 includes a program storage unit 1411 for storing a program for controlling an operation of the electronic device and a data storage unit 1412 for storing data generated while the program is executed.
[0103] The data storage unit 1412 may store data required for operations of an application program 1413 and a beam management program 1414 . In particular, the data storage unit 1412 may store a beam book according to the present invention.
[0104] The program storage unit 1411 includes the application program 1413 and the beam management program 1414 . Herein, a program included in the program storage unit 1411 is a set of instructions and may be expressed as an instruction set.
[0105] The application program 1413 includes an application program which operates in the electronic device. That is, the application program 1413 includes an instruction of an application which is driven by the processor 1422 .
[0106] The beam management program 1414 performs the aforementioned procedure of FIG. 13 .
[0107] That is, the beam management program 1411 monitors current uplink and/or downlink quality, and examines whether the monitored uplink or downlink quality satisfies a pre-set Quality of Service (QoS).
[0108] If the monitored uplink or downlink quality does not satisfy the pre-set QoS, the beam management program 1411 sets a beam training area and determines a beam index for the set beam training area.
[0109] According to the determined beam index, the beam management program 1414 provides the beam index to the RF controller 159 of the beamforming transceiver so that a phase shifter and an MPDT switch for selecting an antenna element can be simultaneously controlled.
[0110] The beam management program 1414 measures channel quality for each beam, and selects a best beam.
[0111] The beam management program 1414 examines whether the selected best beam satisfies the QoS, and repeats the subsequent operations.
[0112] A memory interface 1421 controls an access to the memory 1410 of a component such as a processor 1422 or a peripheral device interface 1423 .
[0113] The peripheral device interface 1423 controls a connection of the processor 1422 and the memory interface 1421 with respect to an input/output peripheral device of a base station.
[0114] The processor 1422 controls the base station to provide a corresponding service by using at least one software program. In this case, the processor 1422 executes at least one program stored in the memory 1410 and provides a service according to the program.
[0115] The input/output controller 1440 provides an interface between the peripheral device interface 1423 and an input/output device such as the display unit 1450 and the input device 1460 .
[0116] The display unit 1450 displays state information, an input text, a moving picture, a still picture, or the like. For example, the display unit 1450 displays information of an application program driven by the processor 1422 .
[0117] The input device 1460 provides input data generated by a selection of the electronic device to the processor unit 1420 through the input/output controller 1440 . In this case, the input device 1460 includes a keypad including at least one hardware button, a touch pad for detecting touch information, or the like. For example, the input device 1460 provides touch information such as a touch, a movement of the touch, a release of the touch, or the like detected through the touch pad to the processor 1422 through the input/output controller 1440 .
[0118] The electronic device includes a communication processor 1490 for performing a communication function for voice communication and data communication, and the communication processor 1490 includes the aforementioned beamforming transceiver 150 and modem 160 of FIG. 1 .
[0119] While various embodiments have been shown and described with reference to certain preferred embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims. Therefore, the scope of the various embodiments is defined not by the detailed description of the invention but by the appended claims, and all differences within the scope will be construed as being included in the present invention. | The present disclosure relates to a pre-5th-generation (5G) or 5G communication system to be provided for supporting higher data rates beyond 4th-generation (4G) communication system such as long term evolution (LTE). An electronic device is provided in a wireless communication system. The device comprises a plurality of antenna sets; a plurality of antenna elements configuring the plurality of antenna sets; an RF transceiver including a plurality of switches for selecting the plurality of antenna elements and a plurality of phase shifters for shifting the phase of a signal transmitted/received through the plurality of antenna elements; and a control unit for determining a beam forming direction and the phase of the signal by simultaneously controlling the plurality of switches and the plurality of phase shifters according to a beambook. | 7 |
BACKGROUND
Typical network processors schedule and queue work such as packet processing operations for upper level network protocols, and allow processing with respect to upper level network protocols (e.g., transport and application layers) in received packets before forwarding the packets to connected devices. The functions typically performed by network processors include packet filtering, queue management and priority, quality of service enforcement, and access control. By employing features specific to processing packet data, network processors can optimize an interface of a networked device. A network processor can be implemented within a system-on-chip (SOC), which can contain several processing cores sharing a common set of resources within the SOC.
SUMMARY
Example methods and systems of the present invention provide for coherent communications between a number of system-on-chips (SOCs). In one embodiment, a data message is generated at a first SOC for transmission to a second SOC, where the first and second SOCs each include a cache and a plurality of processing cores. The data message is associated with one of a plurality of virtual channels. A data block is generated to include data associated with each of the plurality of virtual channels, and includes at least a portion of the data message. Segments of the data block are distributed across a plurality of output ports at the first SOC, and are then transmitted, via the plurality of output ports, to the second SOC.
In further embodiments, the data block may be one of a plurality of data blocks used to transmit the data message. As such, the plurality of data blocks may be generated each to include distinct portions of the data message. Each of the data blocks may be distributed across the output ports for transmission to the second SOC. Likewise, the data message may be one of a plurality of data messages, and each data block may include segments of each of the data messages.
In still further embodiments, the data block can be generated to include one or more segments storing an indicator to confirm that another data block was received correctly at the first SOC from the second SOC. A credit count may be maintained on a per-virtual channel basis at each SOC, which can increment and decrement the credit count in response to receiving or transmitting data blocks or credits that may be indicated within the data blocks. Transmittal of data blocks can be permitted based on an adequate respective credit count.
In yet still further embodiments, the data block may be stored to a retry buffer, which can be accessed in the event of an unsuccessful transmittal, or cleared in response to acknowledgement of a successful transmittal. In order to initialize communications, a first initialization block may be transmitted from the first SOC to the second SOC. Following a response from the second SOC, a second initialization block may be transmitted to the SOC before transmitting data blocks.
In still further embodiments, a system may include a plurality of linked SOCs. For example, a system may include first and second SOCs each having respective input/output (I/O) ports, caches, and a plurality of processors, and each are configured to generate data messages for transmission to another SOC. Each data message is associated with one of a plurality of virtual channels. An interface generates a data block to include data associated with each of the plurality of virtual channels, where the data block includes at least a portion of the data message. Further, the interface causes the data blocks to be transmitted between the first SOC and the second SOC via the I/O ports, where the interface distributes segments of the data block across the first set of I/O ports.
BRIEF DESCRIPTION OF THE DRAWINGS
The foregoing will be apparent from the following more particular description of example embodiments of the invention, as illustrated in the accompanying drawings in which like reference characters refer to the same parts throughout the different views. The drawings are not necessarily to scale, emphasis instead being placed upon illustrating embodiments of the present invention.
FIG. 1 is a block diagram illustrating a system-on-chip (SOC) network services processor in which embodiments of the present invention may be implemented.
FIG. 2 is a block diagram of a network processing system including a plurality of interconnected SOCs.
FIG. 3 is a block diagram of an SOC including a SOC coherent interconnect (SCI) interface.
FIG. 4 is a block diagram of an example data block format.
FIG. 5A is a flow diagram illustrating a process of transmitting data according to a SCI protocol.
FIG. 5B is a timing diagram illustrating receipt of data at a plurality of virtual channels.
FIG. 5C is a diagram of a series of data blocks formed of the data of FIG. 5B .
FIG. 6 is a diagram of a synchronization block control word.
FIG. 7 is a diagram of an idle block control word.
FIG. 8 is a diagram of data block with credit control words.
FIG. 9 is a diagram of data block with poison control words.
FIG. 10 is a state diagram of operation modes under a SOC coherent interconnect (SCI) protocol in one embodiment.
DETAILED DESCRIPTION
Before describing example embodiments of the present invention in detail, an example network processor in which embodiments may be implemented is described immediately below to help the reader understand the inventive features of the present invention.
FIG. 1 is a block diagram illustrating a network services processor 100 . The network services processor 100 delivers high application performance using at least one processor core 120 . The network processor 100 can be implemented within a system-on-chip (SOC), and can be a component of a multiple-SOC system linked by a coherent interconnect as described below with reference to FIG. 2 .
The network services processor 100 processes Open System Interconnection network L2-L7 layer protocols encapsulated in received packets. As is well-known to those skilled in the art, the Open System Interconnection (OSI) reference model defines seven network protocol layers (L1-L7). The physical layer (L1) represents the actual interface, electrical and physical that connects a device to a transmission medium. The data link layer (L2) performs data framing. The network layer (L3) formats the data into packets. The transport layer (L4) handles end to end transport. The session layer (L5) manages communications between devices, for example, whether communication is half-duplex or full-duplex. The presentation layer (L6) manages data formatting and presentation, for example, syntax, control codes, special graphics and character sets. The application layer (L7) permits communication between users, for example, file transfer and electronic mail.
The network services processor 100 may schedule and queue work (packet processing operations) for upper level network protocols, for example L4-L7, and allow processing of upper level network protocols in received packets to be performed to forward packets at wire-speed. Wire-speed is the rate of data transfer of the network over which data is transmitted and received. By processing the protocols to forward the packets at wire-speed, the network services processor does not slow down the network data transfer rate.
A packet is received for processing by a plurality of interface units 122 . A packet can also be received by a PCI interface 124 . The interface unit 122 performs pre-processing of the received packet by checking various fields in the L2 network protocol header included in the received packet and then forwards the packet to a packet input unit 126 . At least one interface unit 122 a can receive packets from a plurality of X Attachment Unit Interfaces (XAUI), Reduced X Attachment Unit Interfaces (RXAUI), or Serial Gigabit Media Independent Interfaces (SGMII). At least one interface unit 122 b can receive connections from an Interlaken Interface (ILK).
The packet input unit 126 performs further pre-processing of network protocol headers (e.g., L3 and L4 headers) included in the received packet. The pre-processing includes checksum checks for TCP/User Datagram Protocol (UDP) (L3 network protocols).
A free-pool allocator 128 maintains pools of pointers to free memory in Level-2 cache memory 130 and external DRAM 108 . The packet input unit 126 uses one of the pools of pointers to store received packet data in Level-2 cache memory 130 or external DRAM 108 and another of the pools of pointers to allocate work queue entries for the processor cores 120 .
The packet input unit 126 then writes packet data into buffers in Level-2 cache 130 or external DRAM 108 . Preferably, the packet data is written into the buffers in a format convenient to higher-layer software executed in at least one of the processor cores 120 . Thus, further processing of higher level network protocols is facilitated.
The network services processor 100 can also include one or more application specific co-processors. These co-processors, when included, offload some of the processing from the cores 120 , thereby enabling the network services processor to achieve high-throughput packet processing. For example, a compression/decompression co-processor 132 is provided that is dedicated to performing compression and decompression of received packets. Other embodiments of co-processing units include the RAID/De-Dup Unit 162 , which accelerates data striping and data duplication processing for disk-storage applications.
Another co-processor is a Hyper Finite Automata (HFA) unit 160 which includes dedicated HFA thread engines adapted to accelerate pattern and/or signature matching necessary for anti-virus, intrusion-detection systems and other content-processing applications. Using a HFA unit 160 , pattern and/or signature matching is accelerated, for example being performed at rates upwards of multiples of tens of gigabits per second. The HFA unit 160 , in some embodiments, could include any of a Deterministic Finite Automata (DFA), Non-deterministic Finite Automata (NFA), or HFA algorithm unit.
An I/O interface 136 manages the overall protocol and arbitration and provides coherent I/O partitioning. The I/O interface 136 includes an I/O bridge 138 and a fetch-and-add unit 140 . The I/O Bridge includes two bridges, an I/O Packet Bridge (IOBP) 138 a and an I/O Bus Bridge (IOBN) 138 b . The I/O Packet Bridge 138 a is configured to manage the overall protocol and arbitration and provide coherent I/O portioning with primarily packet input and output. The I/O Bus Bridge 138 b is configured to manage the overall protocol and arbitration and provide coherent I/O portioning with primarily the I/O Bus. Registers in the fetch-and-add unit 140 are used to maintain lengths of the output queues that are used for forwarding processed packets through a packet output unit 146 . The I/O bridge 138 includes buffer queues for storing information to be transferred between a coherent memory interconnect (CMI) 144 , an I/O bus 142 , the packet input unit 126 , and the packet output unit 146 .
The miscellaneous I/O interface (MIO) 116 can include auxiliary interfaces such as General Purpose I/O (GPIO), Flash, IEEE 802 two-wire Management Interface (MDIO), Serial Management Interrupt (SMI), Universal Asynchronous Receiver-Transmitters (UARTs), Reduced Gigabit Media Independent Interface (RGMII), Media Independent Interface (MII), two wire serial interface (TWSI) and other serial interfaces.
The network services provider 100 may also include a Joint Test Action Group (“JTAG”) Interface 123 supporting the MIPS EJTAG standard. According to the JTAG and MIPS EJTAG standards, a plurality of cores within the network services provider 100 will each have an internal Test Access Port (“TAP”) controller. This allows multi-core debug support of the network services provider 100 .
A Schedule/Sync and Order (SSO) module 148 queues and schedules work for the processor cores 120 . Work is queued by adding a work queue entry to a queue. For example, a work queue entry is added by the packet input unit 126 for each packet arrival. A timer unit 150 is used to schedule work for the processor cores 120 .
Processor cores 120 request work from the SSO module 148 . The SSO module 148 selects (i.e., schedules) work for one of the processor cores 120 and returns a pointer to the work queue entry describing the work to the processor core 120 .
The processor core 120 , in turn, includes instruction cache 152 , Level-1 data cache 154 , and crypto-acceleration 156 . In one embodiment, the network services processor 100 includes 32 superscalar Reduced Instruction Set Computer (RISC)-type processor cores 120 . In some embodiments, each of the superscalar RISC-type processor cores 120 includes an extension of the MIPS64 version 3 processor core. In one embodiment, each of the superscalar RISC-type processor cores 120 includes a cnMIPS II processor core.
Level-2 cache memory 130 and external DRAM 108 are shared by all of the processor cores 120 and I/O co-processor devices. Each processor core 120 is coupled to the Level-2 cache memory 130 by the CMI 144 . The CMI 144 is a communication channel for all memory and I/O transactions between the processor cores 100 , the I/O interface 136 and the Level-2 cache memory 130 and controller. In one embodiment, the CMI 144 is scalable to 32 processor cores 120 , supporting fully-coherent Level-1 data caches 154 with write through. Preferably the CMI 144 is highly-buffered with the ability to prioritize I/O. The CMI is coupled to a trace control unit 164 configured capture bus request so software can later read the request and generate a trace of the sequence of events on the CMI.
The Level-2 cache memory controller 131 maintains memory reference coherence. It returns the latest copy of a block for every fill request, whether the block is stored in Level-2 cache memory 130 , in external DRAM 108 , or is “in-flight.” It also stores a duplicate copy of the tags for the data cache 154 in each processor core 120 . It compares the addresses of cache-block-store requests against the data-cache tags, and invalidates (both copies) a data-cache tag for a processor core 120 whenever a store instruction is from another processor core or from an I/O component via the I/O interface 136 .
In some embodiments, a plurality of DRAM controllers 133 supports up to 128 gigabytes of DRAM. In one embodiment, the plurality of DRAM controllers includes four DRAM controllers, each of the DRAM controllers supporting 32 gigabytes of DRAM. Preferably, each DRAM controller 133 supports a 64-bit interface to DRAM 108 . Additionally, the DRAM controller 133 can supports preferred protocols, such as the DDR-III protocol.
After a packet has been processed by the processor cores 120 , the packet output unit 146 reads the packet data from the Level-2 cache memory 130 , 108 , performs L4 network protocol post-processing (e.g., generates a TCP/UDP checksum), forwards the packet through the interface units 122 or the PCI interface 124 and frees the L2 cache memory 130 /DRAM 108 used by the packet.
The DRAM Controllers 133 manages in-flight transactions (loads/stores) to/from the DRAM 108 . In some embodiments, the DRAM Controllers 133 include four DRAM controllers, the DRAM 108 includes four DRAM memories, and each DRAM controller is connected to a DRAM memory. The DFA unit 160 is coupled directly to the DRAM Controllers 133 on a bypass-cache access path 135 . The bypass-cache access path 135 allows the HFA Unit to read directly from the memory without using the Level-2 cache memory 130 , which can improve efficiency for HFA operations.
The network services processor 100 may be implemented in a system on chip (SOC), by integrating all components of the processor 100 within a single substrate. For applications requiring higher processing capacity, multiple SOCs may be interconnected through a common interconnect as described below with reference to FIG. 2 , where each SOC includes one or more network services processor 100 as shown in FIG. 1 . The interconnect may be referred to as a SOC coherent interconnect (SCI), and may enable processor-to-processor communications for operations such as parallel processing and shared cache or memory access. To enable communications between the SOCs, the network services processor 100 may include a SOC coherent interconnect (SCI) interface 185 . The SCI interface 185 may connect to the CMI 144 to send and receive messages, such as memory requests/responses and work requests/responses, with the processing cores 120 and the L2C 130 . Operation of the SCI interface, as well as the SCI interconnect within a multiple-SOC system, are described in further detail below with reference to FIGS. 2-10 .
FIG. 2 is a block diagram of a network processing system 200 including a plurality of interconnected SOCs 210 A-D. Each of the SOCs 210 A-D may include a network processor such as the processor 100 described above with reference to FIG. 1 , including a respective SCI interface 220 A-D.
The network processing system 200 may be configured to be addressable as a single SOC having multiple network processors, which in turn may be addressable as a single network processor. Thus, the system 200 may interface with external elements in a manner similar to the network processor 100 described above. To provide this capability, the system 200 may include an interface to route external communications to the respective ports at each of the network processors 210 A-D.
Further, to provide coherence among the network processors 210 A-D, the network processors 210 A-D may be linked by a common SCI interconnect 270 at each respective SCI interface 220 A-D. The SCI interconnect 270 may include a bus, series of point-to-point connections, or other combination of channels. The SCI interfaces 220 A-D communicate with one another to send and receive messages, such as memory requests/responses and work requests/responses, thereby providing coherence across the network processors 210 A-D.
The SCI interfaces 220 A-D communicate with one another via a protocol described in example embodiments below, referred to as the SCI protocol. In the examples below, the SCI protocol may be a link-layer, point-to-point protocol that provides for the reliable transmission of multi-core interconnect messages between SOCs, also referred to as nodes. The multicore interconnect messages may be assigned to logical (“virtual”) channels based on a type or class of the message. A substantial number of channels (e.g., 15) enables greater precision in organizing messages and controlling traffic. Messages sent on the same channel may be ordered, while those sent on different channels may be reordered depending on a priority or other configuration.
The messages (also referred to as “data messages”) may be delineated into fixed-size (e.g., 8-byte) words and are packed into fixed-size data blocks (e.g., 64-bytes). For an embodiment implementing 8-byte words and 64-byte data blocks, each data block may contain up to 7 words of data and an 8-byte control word. The control word may be used to specify the block type as well as the form of the control word. Data blocks that contain valid data words may be assigned a sequence number and stored in a retry buffer until the remote link partner returns an acknowledgement. In the event of an error, retransmission may include all blocks newer than the failing sequence number. During transmission, the data block may be striped across a configurable number of physical ports (“lanes”) for transmission via the SCI interconnect 270 .
FIG. 3 is a block diagram of an SOC 310 , including a SCI interface 385 in further detail. The SOC 310 may be configured to include some or all of the elements of the network processor 100 described above with reference to FIG. 1 , and may further be configured within a multiple-SOC system such as the system 200 described above with reference to FIG. 2 . The SCI interface 385 may connect to the CMI 344 to send and receive messages, such as memory requests/responses and work requests/responses, with the processing cores 320 and the L2C 330 . For transmission to external SOCs via the SCI, the SCI interface 385 may include a SCI controller 350 , retry buffer 370 , and output ports 360 including respective first-in-first-out (FIFO) buffers. The SCI controller 530 may interface with the cores 320 and L2C 330 to exchange messages, and operates to classify outgoing data messages by channels, form data blocks comprising those data messages, and transmit the data blocks via the output ports. Transmitted data blocks may also be stored to the retry buffer 370 until receipt of the data block is acknowledged by the receiver.
In this example embodiment, the SCI interface 385 is configured for transmission of data across the SCI interconnect. In order to receive SCI communications, the SOC may include an additional SCI interface (not shown), which may be configured in a manner similar to the SCI interface 385 , with modifications as understood in the art. In particular, a receiving SCI interface may omit a retry buffer, and may include receiver ports in place of output ports. The SCI interface 385 may be configured to have receiver ports in addition to the output ports 360 , where the SCI controller 350 may be configured to process received data blocks and forward corresponding data messages to the processing cores 320 and/or the L2 cache/controller 330 .
FIG. 4 is a block diagram of an example data block 400 . In an example embodiment as described above, outgoing data messages may be delineated into fixed-size (e.g., 8-byte) words and are packed into fixed-size data blocks (e.g., 64-bytes). For an embodiment implementing 8-byte words and 64-byte data blocks, each data block 400 may contain up to 7 words of data (DATAWORD 0 -DATAWORD 6 ) and an 8-byte control word (CONTROL WORD). The control word may be used to specify the block type as well as the form of the control word. The SCI interface (e.g., SCI interface 385 in FIG. 3 ) may generate the data block 400 to include data words according to a predetermined configuration, for example by assigning each data word slot to a given virtual channel.
The data block 400 illustrates a general data block format. In example embodiments, the SCI interface may generate a number of different types of data blocks each having a particular application and format. In example SCI communications described below, four different block formats may be employed, namely sync ( FIG. 6 ), idle ( FIG. 7 ), data with credits ( FIG. 8 ) and data with poison ( FIG. 9 ). The block formats may be distinguished by an indicator, “block type field” included in the respective control word. While all blocks may contain the same number of data words, the validity of the data words can be specified in the control word.
Before describing the particular block formats and their applications, block formation is first described below with reference to FIGS. 5A-C .
FIG. 5A is a flow diagram illustrating a process 501 of forming and transmitting data blocks according to an example SCI protocol. The process 501 may be performed by an SCI interface such as the SCI interface 385 described above with reference to FIG. 3 . With reference to FIG. 3 , a SCI controller 350 receives data messages from the processor cores 320 and/or L2 cache/controller 330 via the CMI crossbar 344 ( 510 ). The data messages may be of a number of different types, such as I/O requests and responses (e.g., inter-SOC work requests and responses) and memory requests and responses (e.g., inter-SOC cache or memory accesses). The data messages may be of any size, as they can be segmented into a number of data words for transmission. The SCI controller 350 may be configured to enable a number of virtual channels (e.g., VC 0 -VC 3 ), where each virtual channel is associated with a specific type of data message. In the example shown in FIG. 3 , I/O requests are assigned to VC 0 , I/O responses are assigned to VC 1 , memory requests are assigned to VC 2 , and memory responses are assigned to VC 3 . In further embodiments, virtual channels may be configured in addition to, or in place of, such channels, including virtual channels assigned to more specific types of work or memory requests/responses, and virtual channels assigned to specific processing cores. Accordingly, the SCI controller classifies each data message by type, assigning each message to a corresponding virtual channel ( 520 ).
The SCI controller 350 then proceeds to generate a stream of data blocks from the data messages at each virtual channel ( 530 ). Each data block may have one or more slots available for data words at each of the virtual channels. Alternatively, if the number of virtual channels exceed the number of data word slots in each data block, the SCI interface may select the virtual channels receiving data word slots from data block to data block. (Such a configuration is described below with reference to FIG. 8 .) Because a data message may be larger than a data word, the data message can be segmented into several data words for distribution among several data blocks. Once the data blocks are formed, the SCI controller 350 forwards the data blocks to a number of output ports 360 for transmission to another SOC ( 540 ). The SCI controller may stripe each data block across the output ports, specifically by distributing individual data words (or other division of the data block) across the output ports in a cyclical order. By striping the data blocks across the output ports, transmission speed may be increased over serial transmission. Further, by generating and transmitting data blocks as described above, the SCI interface 385 may effectively control communications traffic with precision among different message types, as well as prevent interference among competing data messages.
Conversely, when receiving data blocks from a remote SOC, the SCI interface may operate the process 501 in reverse order, with modifications as understood in the art.
FIGS. 5B and 5C show an example data block formation from a set of data messages received to a SCI interface. FIG. 5B is a timing diagram illustrating receipt of data messages at a plurality of virtual channels, while FIG. 5C is a diagram of a series of data blocks formed of the data messages of FIG. 5B . As shown in FIG. 5B , data messages of each type can be received to the SCI interface at any time from time N onward. Those data messages can be processed and assigned to virtual channels as described above with reference to FIG. 5A . Once received and assigned a virtual channel, the data messages may enter a per-virtual channel queue and are inserted into a data block based on their place in the respective queue. Although the ordering shown in based on priority, alternative ordering methods, such as per-channel slot reservation or round-robin, may be implemented. In such a method, ordering may also be based on the availability of data word slots for the respective virtual channel.
As shown in FIG. 5C , the data messages are segmented into individual words and formed into data blocks (BLOCK 0 -BLOCK 2 ). To optimize throughput, the SCI interface may be configured to transmit the data blocks as a continuous stream. To transmit in this manner, the SCI interface may generate data blocks with empty (“invalid”) data words in the event that there are no pending data messages in the virtual channel for the given data word slot. For example, BLOCK 1 includes an “invalid” data word in a slot due to an insufficient number of data words in the VC 3 queue at the time of block formation. Alternatively, the SCI interface may configure the data words of each block dynamically based on the occupancy at each virtual channel queue, thereby minimizing the number of invalid words placed within each data block. In such a configuration, rather than employing predetermined slot assignments, the control word of each block may be configured to identify the virtual channel corresponding to each data word in the block. However, invalid words may still be included if no data messages are available at any virtual channel queue at the time of block formation.
As further illustrated in FIG. 5C , data messages can be segmented into several discrete data words for transmission in a plurality of data blocks. For example, the data message “MEM Rsp 2” in VC 3 is larger than a data word, and therefore is divided into multiple data words, “MEM Rsp 2.0,” “MEM Rsp 2.1” and “MEM Rsp 2.2,” which are then distributed to data blocks BLOCK 1 and BLOCK 2 .
FIGS. 6-9 illustrate example data block formats, each of which may be employed in SCI communications in an example embodiment. FIG. 10 illustrates an SCI communications process by which each of the data block of FIGS. 6-9 may be implemented.
FIG. 6 is a diagram of an example synchronization block (“sync block”) control word. Sync blocks may not contain valid data words or credits, and consequently may not be assigned a sequence number and are not written to the retry buffer. Sync blocks may be used to perform retry handshakes and initialization handshakes between the link partners. A description of each field in the synchronization block is provided in the table below:
TABLE 1
Example control word fields of a synchronization block.
Field
Bit Position
Name
Field Description
63:61
Block type
Sync block indicated by “110”
60
ACK
Acknowledge handshake request.
59:54
0
Zero.
53
Init = 0/
Indicate retry or initialization handshake.
Retry = 1
52
Request
Indicates handshake request.
51:38
TX
Indicates the sequence number that will be
Sequence
assigned to the next TX data block. Used for
Number
verification by the receiver.
37:24
RX
Indicates the sequence number that will be
Sequence
assigned to the next RX data block. Used for
Number
verification by the receiver.
23:0
CRC24
A CRC error check that covers the entire data
block, including the control word with a zero-
filled CRC24 field.
FIG. 7 is a diagram of an example an idle block control word. Idle blocks may not contain valid data words or credits. Consequently, idle blocks may not be assigned a sequence number and may not be written to the retry buffer. However, idle blocks may return block acknowledgements (ACKs). Idle blocks may be sent whenever a SCI interface is not performing a retry/init handshake and either no channel data is ready to be transmitted or no channel credits are ready to be returned.
TABLE 2
Example control word fields of an idle block.
Field
Bit Position
Name
Field Description
63:61
Block type
Idle block indicated by “111”
60
ACK
Acknowledge 2 blocks correctly received.
59:52
0
51:38
TX
Indicates the sequence number that will be
Sequence
assigned to the next TX data block. Used for
Number
verification by the receiver.
37:24
RX
Indicates the sequence number that will be
Sequence
assigned to the next RX data block. Used for
Number
verification by the receiver.
23:0
CRC24
A CRC error check that covers the entire data
block, including the control word with a zero-
filled CRC24 field.
FIG. 8 is a diagram of data block with credit control words. DATA blocks must contain at least one valid data word or channel credits. DATA blocks are assigned consecutive sequence numbers and are written to the retry buffer. DATA blocks may return ACKs, but the ACKs must not be resent during a retry. Therefore, DATA blocks should be written to the retry buffer with ACK=0. ACK insertion should be performed after the retry buffer but before the CRC24 calculation.
TABLE 3
Example control word fields of data block with credits.
Field
Bit Position
Name
Field Description
63:61
Block type
“101” indicates a data block with credits for
virtual channels 14-8. “100” indicates a data
block with credits for virtual channels 7-0.
60
ACK
Acknowledge 2 blocks correctly received.
59:52
Channel
Each bit returns 8 credits for a single channel.
Credits
51:48
D6
Channel for data word 6.
Channel
47:44
D5
Channel for data word 5.
Channel
43:40
D4
Channel for data word 4.
Channel
39:36
D3
Channel for data word 3.
Channel
35:32
D2
Channel for data word 2.
Channel
31:28
D1
Channel for data word 1.
Channel
27:24
D0
Channel for data word 0.
Channel
23:0
CRC24
A CRC error check that covers the entire data
block, including the control word with a zero-
filled CRC24 field.
FIG. 9 is a diagram of data blocks with poison control words. DATA blocks must contain at least one valid data word with an unrecoverable error. An example of such an error would be a double-bit error on the message coming from the local multi-core interconnect unit. The channel poison field will be used to carry the error to the remote link partner.
DATA blocks are assigned consecutive sequence numbers and are written to the retry buffer. DATA blocks may return ACKs, but the ACKs must not be resent. Therefore, DATA blocks should be written to the retry buffer with ACK=0. ACK insertion should be performed after the retry buffer but before the CRC24 calculation.
TABLE 4
Example control word fields of data block with poison.
Field
Bit Position
Name
Field Description
63:61
Block type
“001” indicates a data block with credits for
virtual channels 14-8. “000” indicates a data
block with poison for virtual channels 7-0.
60
ACK
Acknowledge 2 blocks correctly received.
59:52
Poison
Each bit indicates poison to the current
message for the respective channel.
51:48
D6
Channel for data word 6.
Channel
47:44
D5
Channel for data word 5.
Channel
43:40
D4
Channel for data word 4.
Channel
39:36
D3
Channel for data word 3.
Channel
35:32
D2
Channel for data word 2.
Channel
31:28
D1
Channel for data word 1.
Channel
27:24
D0
Channel for data word 0.
Channel
23:0
CRC24
A CRC error check that covers the entire data
block, including the control word with a zero-
filled CRC24 field.
FIG. 10 is a state diagram illustrating a method 1000 of operating SCI communications at a SCI interface, also referred to as a host. The example SCI interfaces described above with reference to FIGS. 1-3 and 5A -C may be configured to operate this method 1000 . Further, the data blocks implemented in the method may include data blocks configured as described above with reference to FIGS. 4 and 6-9 .
Following a reset of a SCI interface ( 1010 ), the SCI interface may enter an initialization mode prior to sending and receiving data blocks ( 1020 ). The initialization state is entered to verify that the SCI interface and receiver are synchronized and able to send and receive data blocks. During initialization mode, a SCI interface may continuously send sync blocks. With reference to the sync block of FIG. 6 , the request/ACK bit may be used to perform a 3-way handshake, whereby the SCI interface manages the request/ACK bits of a continuously sends stream of sync blocks for the purpose of establishing the variables of Table 5 prior to transmission of data blocks. An initialization handshake may be designated a higher priority than a retry handshake. During the initialization mode, SCI interfaces synchronize their starting state by setting respective variables to common values. An example set of variable, and their initial values, are provided in the table below.
TABLE 5
SCI variables and respective initial values upon initialization.
Initial
Item
value
Description
TX_X_SEQ_NUM
0
Sequence number assigned to the next newly formed data block. Used as block write address into retry buffer.
TX_X_ACK_SEQ_NUM
0
Sequence number of the oldest block which has not been acknowledged.
TX_X_RETRY_FULL
0
Indicates the retry buffer has no room to store a newly formed data block.
TX_X_CREDITS(0 . . . 14)
0
Per-channel TX credits. One TX channel credit allows a host to sends one 8-byte data word for the respective
channel. Credits are replenished by the correct reception of data blocks containing TX credits.
RX_X_CREDITS(0 . . . 14)
ALL
Per-channel RX credits, reflecting the number of credits that are scheduled to be returned to the remote link
partner. The initial value of each counter should watch the depth of the respective RX fifo.
RX_X_SEQ_NUM
0
Sequence number assigned to the next correctly received data block. During retry mode, given to remote link
partner to indicate where to begin resending blocks.
TX_X_RET_SEQ_NUM
0
Sequence number of next data block sent during retry mode. Used as a block read addres into the retry
buffer. Seeded by the RX sequence number field received during a retry handshake.
RX_X_ACK_CNT
0
Incremented when a data block is correctly received. Decremented twice when data block sent with ACK = 1.
Cleared during a retry or initialization handshake.
At the completion of a successful initialization handshake ( 1030 ), the SCI interface switches to normal operating mode ( 1040 ). Normal operation mode may be entered upon the exit of initialization mode or the exit of retry mode. Normal mode may be exited whenever a block is received with an error, the link goes down, the node is reset, or a sync block is received.
A number of conditions may be required before a SCI interface may form and send a new data block. A first condition is that the SCI interface be in normal operation mode. A second condition is that TX_X_RETRY_FULL be 0. A third condition is that the SCI interface have either channel credits to return or channel data ready to send. In order for channel data to be considered ready to send, the SCI interface may be required to have the necessary channel credits as indicated by TX_X_CREDITS[channel]. It may not be required that a newly formed data block contain 7 valid data words, or that a newly formed data block contain data words from a single channel. However, it may be required that the newly formed block contain either at least one data word or the return of RX per-channel credits.
When the SCI interface forms and sends a new data block, the SCI interface increments TX_X_SEQ_NUM and writes the data block into the retry buffer at the entry corresponding to the sequence number. In addition, if TX_X_SEQ_NUM equals TX_X_ACK_SEQ_NUM, the SCI interface will set TX_X_RETRY_FULL=1.
Whenever the SCI interface correctly receives a data block that contains an ACK or an idle block that contains an ACK while in normal operation mode, the SCI interface may increment TX_X_ACK_SEQ_NUM twice. Each ACK may acknowledge up to two blocks as being received.
When data is unloaded from one of the per-channel RX data FIFOs, the respective per-channel credits counter RX_X_CREDITS is incremented. This incrementing continues during the retry mode. The SCI interface returns the credits to the remote link partner in groups of 8. Any given RX_X_CREDITS counter is decremented by 8 whenever the SCI interface sends a ‘DATA /w Credits’ block with the respective channel credit bit set.
When a data block is correctly received, RX_X_ACK_CNT may be incremented. This incrementing can continue during the retry mode after the retry handshake completes. RX_X_ACK_CNT may be cleared during a retry or initialization handshake. When a data block is correctly received, TX_X_ACK_SEQ_NUM may also be incremented. This incrementing may also continue during the retry mode after the retry handshake completes. TX_X_ACK_SEQ_NUM may be set to RX_X_SEQ_NUM and is cleared during a retry or initialization handshake.
In the event of an error ( 1050 ), the SCI interface may enter the retry mode ( 1060 ). Retry mode may be entered whenever a block is received with an error, the link goes down, or a SYNC block is received with init/retry=1, Request=1. During the retry mode, the SCI interface may begin sending SYNC block with init/retry=1.
The request/ACK bit may be used to perform a 3-way handshake in the retry mode. During the retry handshake, the SCI interface X may insert RX_X_SEQ_NUM into the RX sequence number field of all transmitted sync blocks. The SCI interface may use the RX sequence number field of received sync blocks to initialize TX_X_RET_SEQ_NUM. In addition, the SCI interface may clear RX_X_ACK_CNT.
Upon the completion of the retry handshake, the SCI interface may begin resending data blocks read from the retry buffer starting at TX_X_RET_SEQ_NUM. Per-channel TX credits may not be required to send, as the corresponding TX credit counters were already decremented while forming the blocks. After reading the data block from the retry buffer, the ACK bit may be set if RX_X_ACK_CNT is >=2. When a retried data block is sent with the ACK bit set, RX_X_ACK_CNT may be decremented twice.
When a data block is resent, TX_X_RET_SEQ_NUM may be incremented. When TX_X_REQ_SEQ_NUM equals TX_X_SEQ_NUM, it is confirmed that blocks have been resent. Once all blocks have been resent and no outstanding error remains, the SCI interface may return to normal operating mode ( 1040 ). In the event that an error occur while resending blocks in the retry mode, the SCI interface may perform a retry handshake as when entering retry mode.
It should be understood that the example flow diagrams presented above can be readily converted to modules, subsystems, or systems that operate in a similar manner as set forth above. For example, the example embodiments may include an initialization module, computing module, and reporting module.
It should be further understood that the examples presented herein can include more or fewer components, be partitioned into subunits, or be implemented in different combinations. Moreover, the diagrams herein may be implemented in hardware, firmware, or software. If implemented in software, the software may be written in any suitable software language. The software may be embodied on any form of computer readable medium, such Random Access Memory (RAM), Read-Only Memory (ROM), or magnetic or optical disk, and loaded and executed by generic or custom processor(s).
While this invention has been particularly shown and described with references to example embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the scope of the invention encompassed by the appended claims. | A network processing system provides coherent communications between multiple system-on-chips (SOCs). Data messages between SOCs are assigned to virtual channels. An interconnect linking the SOCs divides the communications into discrete data blocks, each of which contains data segments from several virtual channels. The virtual channels can be implemented to control congestion and interference among classes of communications. During transmission, the interconnect distributes the data blocks across several physical ports linking the SOCs. As a result, communications between SOCs is optimized with minimal latency. | 7 |
BACKGROUND OF THE INVENTION
[0001] Water is a well-known conductor of electricity. Water also retains excess electrons that create static or stray electricity, which often can be measured in a range of 10-400, or more, millivolts. This stray electricity is detrimental to many, if not most water applications, including livestock watering, crop irrigation, and other uses for plants, animals, and humans wherein cellular metabolism affects biological events.
[0002] Therefore, a primary objective of the present invention is the provision of a means and method for removing electricity from water.
[0003] Another objective of the present invention is the provision of a device for collecting stray electricity in water and for transferring the collected electricity to ground.
[0004] A further objection of the present invention is a provision of a water treatment device through which water flows such that static electricity is removed from the water.
[0005] Still another objective of the present invention is the provision of a method of removing static electricity from water.
[0006] Yet another objective of the present invention is the provision of a method of treating water so as to yield approximately zero millivolts of electricity in the water.
[0007] A further objective of the present invention is the provision of a method and means for removing electricity from water which is economical and safe.
[0008] These and other objectives will become apparent from the following description of the invention.
SUMMARY OF THE INVENTION
[0009] A water treatment device is provided to remove electricity from water. The device includes a pipe through which the water flows. An electrical coil within the pipe collects static or stray electrical voltage, which is then directed through a ground wire connected to the coil to a remote ground location. With the electricity removal device, the method passively and continuously operates to produce water free from stray electricity.
DESCRIPTION OF THE DRAWINGS
[0010] FIG. 1 is a schematic view of one embodiment of the water treatment device for removing electricity, according to the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0011] The present invention is directed towards a device for treating water so as to remove static or stray electricity from the water. The device is generally designated by the reference numeral 10 in FIG. 1 . The device 10 maybe used in conjunction with a second water treatment device 40 , which functions to oxidize detrimental contaminants in the water. The device 40 is described in co-pending patent application Ser. No. ______, entitled “Food Treatment Device”, filed on Mar. ______, 2016in the names of inventors Anthony Gutierrez, Faye Cox-Gutierrez, James Downing, and Verlyn Sneller, which is incorporated herein by reference.
[0012] The electricity removal device 10 includes a pipe 12 through which water flows from an inlet 14 to an outlet 16 . The outlet 16 can be connected to another pipe (not shown) for delivery of the treated water for any desired use or application.
[0013] An electrical coil 18 is mounted within the pipe 12 . More particularly, the coil includes a metal core 20 , such as a steel bar, mounted on a rod or mounting hardware 22 so as to be supported in the pipe 12 . As seen in FIG. 1 , the coil 20 preferably extends axially within the pipe 12 . An electrically conductive wire 24 is spirally wrapped around the core 20 so as to form the coil 18 . In FIG. 1 , the wire 24 is illustrated with spacing between the spiral sections, though it is understood that the wire 24 can be wrapped closely and tightly on the core 20 , with little if any spacing between the coil wire revolutions.
[0014] The mounting bracket or rod 22 has a threaded end extending out of the pipe 12 , and is secured by a washer 26 and a nut 28 . A grounding wire 30 is connected to the end of the rod 22 , such as by a grounding nut 32 , and extends to a ground source 34 , such as a grounding stake or post inserted into the earth.
[0015] In operation, water enters an inlet 36 for the treatment device 40 , and then exits into a conduit 38 , which in turn is connected to the inlet 14 of the pipe 12 . The water then passes through the pipe 12 wherein the stray electrical voltage is collected by the core 20 of coil 18 before the water exits the outlet 16 . The collected electricity is transferred or transmitted by the ground wire 30 to the ground 34 .
[0016] Preliminary tests of treating water with the device 10 for livestock consumption have shown beneficial results. In one pig farming trial, use of the electricity removal device 10 increased water intake by the pigs by approximately 20-30%, over and above a 20-25% increase when using the treatment device 40 by itself. The pigs look better, are more even in size, and have more energy. There is less sickness and death loss. The pigs require less chemicals and medicine. The pigs who drink water from the treatment system 10 and 40 have better feed conversion, with less feed required to achieve the desired kill weight. Grow out to kill weight is also faster using the water treatment device 10 . Generally, the pigs are in all-around better health drinking water that has been treated to remove electricity.
[0017] In a second pig farming test, two barns were used, with 1,000 nursery feeder pigs contained in each barn. An electron removal device 10 was used in combination with the treatment device 40 in the first barn, while the second barn used neither device. When the water treatment system was installed, the nursery pigs were one month into the two month term. Each barn had separate water meters. Within two hours after the system was installed in the first barn, the water meter for the first barn showed more water activity than in the second barn. In the first week, water consumption in the first barn was consistently 20-30% more than in the second barn. After the first week, the ground wire 30 for the treatment system of the first barn was unhooked for two days so that electricity was not being transferred from the coil to the ground, which resulted in a 15% decrease in water consumption. When the ground wire 30 was reconnected, water usage again increased by 30% over the untreated water usage in the second barn. At the end of the third week, a visual inspection of the pigs showed that body size, alertness, and general spunkiness were greater for the animals in the treated barn. Also, the eyes of the pigs in the first barn were more prominent and clear, than the eyes of the pigs in the second barn, which were sunken, bloodshot, or draining. This improved condition of the pigs' eyes is a good sign of proper hydration, as compared to the dehydrated condition of the pigs in the second barn. Each of the barns also had their own manure and urine pits, which were measured before and after the tests. After 30 days, the pits of both barns had risen the same level, indicating that the pigs in the first barn, who consumed approximately 30% more water than the pigs in the second barn, had metabolized the extra water, which confirms the improved overall condition of the pigs in the first barn. During this test, the device 10 measured 175 millivolts of removed electricity.
[0018] The water treatment device 10 can be used alone, or in combination with the treatment device 40 . Water treated by the device 10 to remove electricity can be used in numerous and unlimited applications, such as live stock and animal watering, crop irrigation, hydroponics, aquaponics, green house watering, dairy operations, natural and made man water ponds, lakes, pools, lagoons, waste pits, and sanitization systems, desalination, commercial and residential usage for human consumption and for cleaning purposes, meat and plant processing, ethanol production, medical cleansing and sterilization, oil separation, fracking, chemical reactors and processors, and other uses and applications were untreated water has previously been utilized.
[0019] The invention has been shown and described above with the preferred embodiments, and it is understood that many modifications, substitutions, and additions may be made which are within the intended spirit and scope of the invention. From the foregoing, it can be seen that the present invention accomplishes at least all of its stated objectives. | A water treatment device is provided to remove static or stray electricity from water. The device includes a pipe though which the water flows, with an electrical coil within the pipe. The coil captures or collects the electricity and transmits electricity to ground via a ground wire. | 2 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates generally to game tickets for playing games of chance, and in particular to a game ticket assembly and a play method with a multipurpose band printed with promotional indicia in a confusion pattern for advertising and security.
2. Description of the Prior Art
Various types of prior art devices have been used for playing games of chance for money and other prizes. For example, philanthropic, fraternal and social organizations often conduct charity gaming events for fundraising purposes. Moreover, various commercial establishments generate income and provide entertainment for their patrons by operating games of chance. Cards, tickets and other devices are commonly used to determine the game outcome at random or by chance.
Game symbols are often printed on such devices for identifying winners, losers and prize amounts. The game symbols can be concealed from the players until the game is in play, whereupon the concealed game symbols are somehow revealed to the players. For example, a set of game cards can be manufactured with a predetermined combination of winning and losing cards, as determined by combinations of game symbols printed thereon. The game symbols can be initially concealed by suitable concealing means, such as break-open windows or scratch-off coatings.
Another type of gaming device utilizes a set of game tickets printed with the game symbols and folded in such a way that the game symbols are concealed. The tickets can be used individually or in groups of multiple tickets fastened together. Such ticket assemblies can be secured together with the game symbols concealed until the ticket assemblies are bought and played. Ticket assemblies of this type are often sold from point-of-purchase displays. For example, a set of game tickets can be placed in a suitable receptacle, such as a jar. The jar can serve the dual purposes of displaying and holding a set of jar ticket assemblies. The game ticket assemblies can then be purchased at random from the jar and played.
Aesthetics are an important consideration in designing materials for playing games of chance. The game cards or tickets should help to promote the game by attracting players and stimulating player interest. Common devices for promoting a game of chance include point-of-sale advertising flares and artwork on the tickets themselves.
Another important consideration in designing game materials relates to security. With games of chance involving monetary and other prizes, game integrity and security are important considerations to prevent awarding unearned prizes and incurring loses. For games involving hidden game symbols, security measures typically involve concealing the game symbols until the card or ticket is purchased and played. One method of concealing a game symbol prior to play involves securing a band around folded parts of the game tickets. The band can comprise a fungible material, such as paper, and can be adhesively secured or stapled to the tickets.
Heretofore there has not been available a game ticket assembly with the advantages and features of the present invention in the areas of advertising the game and providing security therefor.
SUMMARY OF THE INVENTION
In the practice of the present invention, a game ticket assembly includes one or more individual game tickets. Each ticket is printed with a game symbol, which can comprise either a winning symbol or a losing symbol. The winning symbols can vary according to the prize amounts associated with each. The game materials form a set comprising a plurality of game ticket assemblies. The game tickets are folded to conceal the game symbols and are secured in their folded, closed configurations by a band printed with indicia in a confusion pattern for identifying a commercial entity associated with the game materials. The confusion pattern provides security by concealing the hidden game symbols.
OBJECTS AND ADVANTAGES OF THE INVENTION
The principle objects and advantages of the present invention include: providing a game material set with multiple game ticket assemblies; providing such game ticket assemblies with multiple or individual tickets; providing such game ticket assemblies with game symbol sections which have folded configurations prior to play and open configurations to reveal the hidden game symbols; providing such a game ticket assembly which includes a band releasably securing the game tickets in their folded configurations; providing such a game ticket assembly which includes confusion pattern printing on the band; providing such a game ticket assembly which facilitates game security through the confusion pattern printing on the band; providing such a game ticket assembly which includes promotional indicia associated with a commercial entity printed in a confusion pattern on the band; providing such a game ticket assembly which enhances player interest; providing such a game ticket assembly which enhances game security; providing such a game ticket assembly which can be manufactured on existing game ticket manufacturing equipment with preprinted bands; and providing such a game ticket assembly which is economical to manufacture, efficient in operation and particularly well adapted for the proposed usage thereof.
Other objects 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 DRAWINGS
FIG. 1 is a perspective view of a game ticket assembly embodying the present invention, shown in a closed, concealed configuration with identifying indicia printed in a confusion pattern on a band thereof.
FIG. 2 is a perspective view of the game ticket assembly with the band broken and the tickets partially unfolded.
FIG. 3 is a perspective view of the game ticket assembly with the band broken and the tickets unfolded to an open configuration.
FIG. 4a is an enlarged, longitudinal cross-sectional view of the game ticket assembly taken generally along line 4a--4a in FIG. 1.
FIG. 4b is an enlarged, longitudinal cross-sectional view of the game ticket assembly taken generally along line 4b--4b in FIG. 3.
FIG. 5 is a perspective view of a game ticket assembly comprising a first modified embodiment of the present invention with promotional indicia comprising a logo printed in a confusion pattern on the band.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
I. Introduction and Environment
As required, detailed embodiments of the present invention are disclosed herein; however, it is to be understood that the disclosed embodiments are merely exemplary of the invention, which may be embodied in various forms. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a basis for the claims and as a representative basis for teaching one skilled in the art to variously employ the present invention in virtually any appropriately detailed structure.
Certain terminology will be used in the following description for convenience in reference only and will not be limiting. For example, the words "upwardly", "downwardly", "rightwardly" and "leftwardly" will refer to directions in the drawings to which reference is made. The words "inwardly" and "outwardly" will refer to directions toward and away from, respectively, the geometric center of the embodiment being described and designated parts thereof. Said terminology will include the words specifically mentioned, derivatives thereof and words of a similar import.
Referring to the drawings in more detail, the reference numeral 4 generally designates a game ticket assembly embodying the present invention. A set of game ticket assemblies 4 are adapted for placement in an appropriate receptacle, such as a jar, from which the game ticket assemblies 4 can be extracted at random as they are purchased. A master game card or flare (not shown) identifying the winning game symbols and corresponding prize amounts can also be placed in the jar in view of the players.
II. Game Ticket Assembly 4
The game ticket assembly 4 includes one or more individual game tickets 10 each having game symbol and extension ends 10a,b; upper and lower edges 10c,d; and front and back faces 10e,f. Each game ticket 10 also includes game symbol and extension sections 10g,h adjacent to the game symbol and extension ends 10a,b respectively.
A first fold line 10i demarcates the game symbol and extension sections 10g,h respectively and a second fold line 10j located within the game symbol section 10g divides same into proximate and distal portions 10k,l respectively. The fold lines 10i,j extend between the upper and lower edges 10c,d and are generally parallel to the ends 10a,b. A game symbol 12 is printed on the inner face 10e in the game symbol section 10g and can comprise any one of the game symbols involved, including a winning symbol corresponding to a prize amount or a losing symbol.
The individual game tickets 10 can be used singly or in multiples to form game ticket assemblies 4. In manufacturing a multi-ticket configuration, the game tickets 10 can first be stacked in their open, unfolded configurations. They are then collectively folded along their second fold lines 10j and then collectively folded again along their first fold lines 10i whereby each individual ticket 10 forms a triple-thickness concealed end 14 of the game ticket assembly 4 in a closed position thereof.
The game ticket assembly 4 is retained in its closed position by a band 16. The band 16 has first and second ends 16a,b; first and second longitudinal edges 16c,d and inner and outer faces 16e,f. The band 16 has a width W B defined as the spacing between its edges 16c,d. W B is slightly less than the width W T of the ticket assembly concealed end 14, which approximates the spacing between the first fold line 10i and the second fold line 10j. The band inner face 16e can be printed with a relatively opaque coating 16g. For example, printing the band inner face 16e with black or some other suitable dark color can provide a degree of security by further concealing the hidden game symbol 12. The band is suitably fastened to the concealed end 14 by a fastener such as adhesive 18.
The game ticket assembly 4 described thus far is conventional and well-known in the prior art. The externally-printed band which, in combination with the other features of the game ticket assembly 4, forms the present invention, is described next.
The band outer face 16f is printed with a plurality of indicia 16h which can comprise, for example, the name (e.g., "ACME") of the manufacturer, distributor or dealer of the ticket assembly 4. The identifying indicia 16h forms a confusion pattern 16i on the band outer face 16f. The confusion pattern 16i is preferably relatively closely spaced with relatively small intermediate spaces 16j therebetween in order to provide the desired level of security.
A game ticket assembly 104 comprising a first modified embodiment of the present invention is shown in FIG. 5 and includes a band 110 with a plurality of symbol indicia 112 printed thereon. The symbol indicia 112 can correspond, for example, to the logo of a source (e.g., manufacturer, distributor, etc.) of the game ticket assembly 104. By printing a confusion pattern 114 comprising symbol indicia 112 on the band 110, the security objective described above can be realized. Moreover, by using a logo or symbol associated with the source of the game ticket assembly 104, the band 110 can serve an advertising and promotional purpose. Since the outer surface of the band 110 is generally in plain view of a player, a commercial impression can be conveyed with the confusion pattern 114.
III. Operation
The game ticket assemblies 4 are typically sold individually for a predetermined price each for which the player receives a number of chances at winning which corresponds to the number of individual game tickets 10 in an assembly 4. The number of winning game symbols 12 in the game material set is based upon the prize amount or amounts and the total ticket count. A predetermined payout represents a percentage of all income received from ticket sales, with the remaining percentage representing the percentage profit.
In operation, the band 16 serves several purposes. First of all, it binds the individual game tickets 10 together at the concealed end 14 of a game ticket assembly 4.
Secondly, the band 16, in cooperation with the indicia 16h forming the pattern 16i thereon, functions to provide a measure of security to prevent learning the nature (i.e., winning or losing) of the game symbol 12 until the game ticket assembly 4 is purchased and opened by a player. The combination of the triple-folded concealed end 14, the confusion pattern 16i or 114 and the opaque band coating 16g cooperate to provide security. The concealed end 14 is folded in such a way that it cannot be opened without tearing or otherwise removing the band 16, thus providing a tamper-evident measure of security.
Still further, the band 16 prominently identifies the manufacturer, distributor or dealer of the game ticket assembly 4 by prominently displaying its indicia 16h or 112 in a confusion pattern 16i or 114. The indicia 16h or 112 provides a measure of security against counterfeit tickets which might be brought in from other sources to collect prizes, and further guards against viewing the hidden game symbols 12, for example, with the aid of a bright light, etc. The confusion pattern 16h or 112 formed by the indicia 16i tends to obscure the concealed game symbols 12. Thus, the possibility of the hidden game symbols 12 being detected is reduced.
It is to be understood that while certain forms of the present invention have been illustrated and described herein, it is not to be limited to the specific forms or arrangement of parts described and shown. | A game ticket assembly is provided with a printed band whereby game symbols printed on the ticket are obscured and a commercial entity associated with the ticket is promoted. The trade name or logo of the commercial entity is printed on the band in a repeating confusion pattern and is observable by players. | 8 |
CONTRACTUAL ORIGIN OF THE INVENTION
The United States Government has rights in this invention pursuant to Contract No. W-31-109-ENG-38 between the U.S. Department of Energy and the University of Chicago representing Argonne National Laboratory.
This is a continuation of application Ser. No. 564,112, filed Dec. 21, 1983, now abandoned.
BACKGROUND OF THE INVENTION
This invention relates generally to apparatus for removing impurities from the plasma in a fusion reactor, and, more particularly to apparatus for removing the helium ash from a deuterium-tritium plasma.
The most likely fuel for a fusion reactor is deuterium and tritium, which produces alpha particles (helium nuclei) and neutrons. The neutrons produced escape through the walls of the plasma confinement device and are used in generating useful external heat. The alpha particles slow down and collect in the plasma as a helium impurity. Minute amounts of oxygen may also be present as an impurity. Since continuous operation of a fusion reactor requires continuous removal of the fusion by-products and other impurities, the helium ash must be continuously removed from the plasma.
A current method of helium removal involves the limiter, which serves to position the plasma away from the confinement device walls. Typically slots are provided in the limiter. Helium that drifts through the limiter slots is exhausted by a vacuum duct system behind the limiter. Another method involves a divertor, which is usually positioned below the plasma, away from the limiter. A magnetic field is used to divert the escaping alpha particles away from the plasma, where they form helium atoms, which are exhausted by a vacuum duct system. While the vacuum duct system is believed to provide adequate impurity control, it requires extensive structural components which must be fitted to the fusion reactor. Also, since some of the fuel ions would also be swept away in the vacuum system, the tritium must be recycled and a larger inventory of tritium must be available for the reactor.
Therefore, it is an object of the present invention to provide an apparatus for removing impurities from the plasma in a fusion reactor without an external vacuum pumping system.
It is also an object of the present invention to provide an apparatus for removing the helium ash from a fusion reactor.
It is another object of the present invention to provide an apparatus which removes helium ash and minimizes tritium recycling and inventory.
Additional objects, advantages, and novel features of the invention will be set forth in part in the description which follows, 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.
SUMMARY OF THE INVENTION
To achieve the foregoing and other objects and in accordance with the purposes of the present invention, apparatus for removing impurities from a fusion reactor having a hydrogen plasma may comprise: an impurity trapping site within the reactor plasma confinement device, said trapping site being formed of a trapping material having negligible impurity solubility and relatively high hydrogen solubility; and means for depositing said trapping material on said trapping site at a rate sufficient to prevent saturation of impurity trapping. Preferably, the apparatus will remove helium and oxygen.
High energy particles (such as deuterium, tritium and helium) impinging on material surfaces become trapped within the material up to saturation levels which depend on the particle species and energy, the type of material, and the material temperature. Since a fusion reactor uses hydrogen (in the form of deuterium and tritium) as fuel and produces helium as ash, a suitable trapping material must trap helium better than hydrogen. Several materials have been shown to trap helium preferentially over hydrogen: nickel, iron, vanadium, niobium, and tantalum. The selective trapping in certain metals is a result of the negligible solubility of helium compared with the relatively high solubility of hydrogen in the lattice. The impinging helium diffuses through the lattice until it reaches a trapping site where it comes out of solid solution. Hydrogen, on the other hand, remains in solid solution until it diffuses to the surface and escapes. Thus, the trapping material acts as a selective helium pump. However, helium trapping occurs only up to a saturation level, typically 10 17 -10 18 /cm 2 , after which it is released at the same rate of impingment. In order to pump helium usefully in a fusion reactor, i.e. to achieve long burn times (approaching six months), the trapping surface must be continuously replated at a rate to prevent saturation of helium trapping.
Although helium is by far the most abundant impurity in a fusion reactor, trace amounts of oxygen may also be present. It has been found that the materials which preferentially trap helium also preferentially trap oxygen.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention is illustrated in the accompanying drawings wherein:
FIG. 1 is a conceptual view of the self-pumping system.
FIG. 2 is a graph of heat flux and surface growth for a self-pumped divertor using a high-Z material such as tungsten.
FIG. 3 is a graph of equilibrium hydrogen concentration at 0.13 Pa hydrogen pressure and hydrogen solid solubility in various refractory metals.
DETAILED DESCRIPTION OF THE INVENTION
Referring to FIG. 1, trapping site 10, which may be the front face of a limiter, the limiter slot region, or a divertor plate, is positioned within plasma confinement device 12. When deuterium and tritium ions impinge on trapping site 10, they diffuse out as deuterium and tritium atoms. When helium nuclei (alpha particles) impinge on trapping surface 10 they are trapped. The trapping surface is replenished by injecting metal particles (Z°) into the plasma, which strips them of their electrons forming metal ions. The metal ions then deposit on trapping surface 10, which grows continuously at a rate to prevent helium saturation.
There are several material requirements for selective helium pumping: high hydrogen solubility; high hydrogen diffusivity; absence of hydride formation; high thermal conductivity; adequate operating temperature window; high probability of helium trapping (≧0.25); high saturation trapping level; and self-sputtering coefficient <1. Only a few materials meet these requirements. Low Z materials such as beryllium and carbon tend to trap hydrogen as well as helium. Iron and nickel do not have adequate thermal conductivity to accommodate the high heat fluxes near the plasma. Titanium and zirconium form hydrides at low hydrogen concentrations. The materials which appear to meet the above requirements best are vanadium, niobium, tantalum, tungsten, and molybdenum. Although the first three metals are known to form hydrides, they have high hydrogen solubilities. These metals are also considered high-Z materials and can only be used at low particle energies due to self-sputtering limitations.
TABLE I______________________________________Parameters for Self-Pumping System Using a DivertorParameter Value______________________________________Concept Self-pumped divertorPlasma temperature at separatrix, eV 50Helium production rate, s.sup.-1 2.2 × 10.sup.20Helium trapping rate, s.sup.-1 2.2 × 10.sup.20Area of plate, m.sup.2 32Metal (vanadium, etc.) current to plate, s.sup.-1 1.1 × 10.sup.21Energy of helium ions striking plate 450(at separatrix), eVEnergy of D-T ions striking plate 300(at separatrix), eVEnergy of redeposited metal ions striking ≲700plate (at separatrix), eV______________________________________
At low plasma edge temperature (50 eV at separatrix) a vanadium coated divertor plate (see Table I) would be capable of pumping 2.2×10 20 helium ions per second. Particles entering the slot region of a typical divertor impinge on a neutralizer plate coated with vanadium where a significant fraction of the helium particles are trapped. The escaping D-T particles are allowed to flow out of the divertor and re-enter the plasma scrape-off region. The surface of the neutralizer plate is continuously deposited with incoming metal atoms at a rate that is sufficient to prevent helium saturation. Metal can be added to the plasma, either by pellet injection or by vaporization of metal rods.
The helium saturation trapping fraction in vanadium is of the order of 20%. Therefore 10 21 vanadium atoms per second must be deposited to trap the helium continuously.
A REDEP code simulation of a self-pumped divertor surface was performed and the results shown in FIG. 2. Tungsten is believed to be representative of the other high-Z metals and was added at the rate of 10 21 atoms/sec. As shown in FIG. 2 at the end of six months of continuous operation, the surface has grown by a maximum of 0.6 cm. The effect on this growth to the surface heat flux, as shown in FIG. 2, is negligible. The total volume of material used during a 6 month period is 0.25 m 3 . This is an acceptable amount of trapping material to achieve a lifetime of 6 months continuous burn cycle or one year at 50% burn cycle.
A limiter system would give the same results as the above divertor system at low temperatures. However, at low temperatures the limiter would not need leading edges, only a front face.
TABLE II______________________________________Parameters for Self-Pumping System Using Limiter Slot TrappingParameter Value______________________________________Concept Double-edged limiter with two slotsFront face material BerylliumSlot material Vanadium, etc.Plasma edge temperature, eV 150Temperature at slot, eV 50Helium production rate, s.sup.-1 2.2 × 10.sup.20Helium current to limiter, s.sup.-1 2.2 × 10.sup.21Helium entering slots, % 10Total neutralizer plate areas, m.sup.2 ˜10Metal (vanadium, etc.) current to 1.1 × 10.sup.21plate, s.sup.-1Energy of redeposited metal ions striking ≲700plate (maximum), eVHeat flux to plate, MW/m.sup.2 ≲1Plate operating temperature, °C. ≳150______________________________________
At higher plasma edge temperatures (150 eV) a limiter slot system may be used (see Table II). A low-Z material is used for the limited front face to minimize erosion from self-sputtering. Vanadium is used for the slot region to trap helium. While most of the vanadium is confined to the slot region, some of the beryllium would be transferred from the front face to the slot region. The average rate of buildup over 10 m 2 of neutralizer plate to pump 2×10 20 helium atoms per second is estimated to be 2×10 -9 μm/s or 4.8 cm/yr for continuous operation.
For a system using the limiter front face for trapping, metal injection into the plasma by pellets or puffing is probably the simplest technique. The amount of metal is small compared to the D-T flux and vaporization can be easily achieved in the plasma edge.
For the divertor system or limiter slot system the simplest technique would be to position metal rods or bars of the trapping material in the scrape-off or slot regions to allow the incoming D-T flux to vaporize the metal surface. The vaporized atoms would then be swept into the neutralizer plate with the D-T particle flow. At temperatures greater than 1950° K. a metal rod of vanadium having a surface area of <1 m 2 would supply 10 21 atoms/sec. The amount of vaporization can be easily controlled by adjusting the height to which the rods are inserted into the slot region.
An important consideration for vanadium is the possibility of a high retained D-T concentration in the surface layer causing hydride formation. The equilibrium concentration depends upon several factors, including the hydrogen diffusion rate, the hydrogen recombination rate at the surface, and the hydrogen partial pressure in the slot region. The hydrogen concentration in vanadium at 15 Pa (10 -3 torr) along with the hydrogen solubility are shown in FIG. 3. All values for hydrogen concentration are well below the concentrations needed for hydride formation.
A self-pumping helium removal system has been described. Such a system eliminates all vacuum ducts and pumps (except for a small start-up system). At low temperatures a simple limiter without leading edges could be used or a simplified divertor system. | Apparatus for removing the helium ash from a fusion reactor having a D-T plasma comprises a helium trapping site within the reactor plasma confinement device, said trapping site being formed of a trapping material having negligible helium solubility and relatively high hydrogen solubility; and means for depositing said trapping material on said site at a rate sufficient to prevent saturation of helium trapping. | 8 |
PRIOR ART
The present invention relates to a method of processing postal items in a postal sorting machine in order to prepare delivery rounds or “postmen's walks” in a plurality of sorting passes, typically two sorting passes. The invention applies more particularly to a postal sorting machine having a carrousel of trays, in which the postal items travel in the trays above sorting outlets.
Present-day sorting machines are not capable of completely avoiding sorting errors while preparing delivery rounds. A sorting error in a delivery round gives rise to an item being wrongly placed in the delivery round. By way of example, a sorting error may be due to multiple items being taken simultaneously as a bunch during a first pass, but it can also be due to errors in the handling of items between two sorting passes (e.g. an operator inverting articles while they are being loaded onto the feed magazine).
The consequence of one or more sorting errors in a delivery round is a non-negligible extra expense for the postal operator in charge of delivering the mail. That is why known methods of processing postal items in a sorting machine make use of various monitoring means, and in particular means for automatically checking whether multiple items have been taken as a bunch and for directing such items taken as a bunch of multiple items to a reject outlet where they are recovered for manual sorting. For example, U.S. Pat. No. 6,316,741 describes a method of processing postal items in which a monitoring of the sequence in which items pass through is performed in order to detect sorting errors. In the known method, in case of the detection of a sorting error, a manual sort is performed on the detection identified item. Manually inserting items into a stack of sequenced articles in order to remedy sorting errors is expensive in terms of operator time and delay.
The object of the invention is to propose a method of processing postal items that makes it possible to avoid sorting errors in delivery rounds and that also makes it possible to increase the proportion of items that are sorted automatically.
SUMMARY OF THE INVENTION
The idea according to the invention is to perform a rank monitoring in a machine for sorting postal items having a carrousel of trays consisting in checking during a sorting pass, for each current item, data representative of an order number or rank allocated to the distribution point corresponding to the current postal item in a predetermined sequence of distribution points to run through this sorting pass in order to prepare each delivery round; the checking consisting in monitoring how rank varies for successive postal items in order to detect any difference relative to said predetermined sequence; and, based on this rank monitoring, i.e. in response to said detection for a current item, the machine is controlled so as to cause the current item to recirculate through the machine so as to retard the sorting of the current item and thus recreate the expected sequence by making this current item carrying out one complete revolution round the carrousel. To summarize, the invention take advantage of the recirculation possibilities given by a machine having a carrousel of trays in order to correct sorting errors resulting for example of a defective unstacking of the postal items. This consists in deciding to recirculate items checked as out of the rank through monitoring instead of rejecting them. The current item is then expected to be, after a complete revolution round the carrousel, in sequence with the items surrounding it, at the time for a new sorting decision, because its rank might then correspond to the current rank. The rank monitoring has then further for purpose to ensure that after a revolution of the carrousel, the current item is, or is not, in sequence. The rank monitoring further consists in observing the rank of the current postal item in a portion, or “observation window”, of said sequence constituted by a certain number of consecutive postal items
More particularly, the invention provides a method of processing postal items in order to prepare delivery rounds by performing a plurality of sorting passes through a postal sorting machine having a carrousel of trays in which the postal items travel in trays above the sorting outlets and are deposited in the appropriate sorting outlets, the method comprising the steps consisting in: checking in the machine during a sorting pass, for each current item, data representative of an order number or rank allocated to the distribution point corresponding to the current postal item in a predetermined sequence of distribution points to run through this sorting pass in order to prepare each delivery round; the checking consisting in monitoring how rank varies for successive postal items in order to detect any difference relative to said predetermined sequence; the method being characterized in that in response to said detection of a difference for a current postal item: the rank of the current postal item is observed in a portion, or “observation window”, of said sequence constituted by a certain number of consecutive postal items and if the rank of the current postal item is one less than a current rank; a first number of postal items of rank one more than the rank of the current postal item is counted in the observation window and a second number of postal items having the same rank as the current postal item is counted in said window; and if the first number is less than a determined first threshold S 1 and the second number is greater than a determined second threshold S 2 , then the machine is controlled so as to cause the current postal item to be deposited in the appropriate sorting outlet; whereas if the first number is greater than the determined first threshold S 1 and/or the second number is less than the determined second threshold S 2 , then the machine is controlled so as to cause the current postal item to return to the observation window after making one complete revolution round the carrousel.
Consequently, according to the invention, in response to a sorting error being detected for the current item, the current item is caused to recirculate through the machine so as to retard its sorting and thus recreate the expected sequence.
If a two-pass sorting plan is used in which the distribution points of each round are shared successively over N 1 sorting outlets of the machine during a first pass with the last distribution point of any one round being followed immediately by the first distribution point of another round, and in which the distribution points allocated to the N 1 sorting outlets during the first pass are shared during a second pass over N 2 outlets of the machine while following a certain order in the processing of the N 1 sorting outlets, in the method of the invention, it is possible by monitoring rank during the second sorting pass to detect that a current postal item is present in the machine in a manner that is not correct according to the sorting plan and will therefore be wrongly placed during the delivery round. For example, the current postal item may be a postal item that was taken as part of a bunch during the first sorting pass but that has been taken separately during the second pass, or else an item that was unstacked in front of the item preceding it. The method of the invention makes it possible to detect sorting errors and to cause postal items to be put back into circulation in the machine so as to restore coherence in the order of the postal items by deferring machine sorting of critical postal items, when that is possible, instead of merely sending them to a reject outlet.
In a particular implementation of the method of the invention, observations are also made in the observation window of the sorting outlets in which a certain number of consecutive postal items ought to be located, and if the first number is greater than the first determined threshold S 1 and/or the second number is less than the second determined threshold S 2 , and if no postal item of rank one more than the rank of the current postal item is to be placed in the sorting outlet in which the current postal item is placed, then the machine is instructed to place the current postal item in the appropriate sorting outlet.
The invention extends also to a method of processing postal items in order to prepare delivery rounds by performing a plurality of sorting passes through a postal sorting machine having a carrousel of trays in which the postal items travel in trays above sorting outlets and are deposited in the appropriate sorting outlets, wherein the method comprises the steps in which if it is detected that a postal item transported in the machine by the carrousel of trays can not be deposit into a sorting outlet, this postal item is caused to recirculate by controlling the machine in order this postal item performs a complete revolution round the carrousel. In this method, it can be appreciated that the recirculation can be controlled by a detection of the type of a rank monitoring but also for example of the type of a verification of the unavailability of a sorting outlet in the machine. Naturally, this method can be implemented in juxtaposition with a step of checking in the machine during a sorting pass, for each current item, data representative of an order number or rank allocated to the distribution point corresponding to the current postal item in a predetermined sequence of distribution points to run through this sorting pass in order to prepare each delivery round; the checking consisting in monitoring how rank varies for successive postal items in order to detect any difference relative to said predetermined sequence. The rank monitoring allows then to ensure that a recirculated postal item can, or not, be sorted and does not create a sequencing error. This monitoring method before choosing the sanction to apply to a recirculated postal item allows the implementation of a recirculation function during a second sorting pass, which was until now impossible because it was not known if the sort of such a recirculated postal item would, or not, disturb the sorting sequence.
The invention extends to a carrousel of trays type sorting machine specially designed to implement the above-defined methods of processing postal items.
Rank monitoring in accordance with the invention can also be used during a second sorting pass to synchronize the merging of different batches of items coming from respective first sorting passes on different sorting machines.
The invention can be better understood on reading the following description and on examining the accompanying figures. This description is given purely by way of indication and is not limiting on the invention in any way.
BRIEF DESCRIPTION OF THE FIGURES
FIG. 1 is a very diagrammatic view of a carrousel postal sorting machine with trays arranged to implement the method of the invention.
FIG. 2 shows an observation window for monitoring rank in accordance with the invention.
FIG. 3 is a flow chart showing various steps in monitoring rank in accordance with the invention.
FIG. 4 is a table showing an example of the operation of the method of the invention.
FIG. 5 is a flow chart showing a second way of implementing the method in accordance with the invention.
FIG. 6 is a flow chart showing a third way of implementing the method in accordance with the invention.
DETAILED DESCRIPTION OF THE INVENTION
In FIG. 1 , there can be seen a machine 1 for sorting postal items 2 , the machine comprising a carrousel 3 , or annular circulating conveyor, of trays. The postal items 2 are serialized by an unstacker (not shown) at the inlet of the machine, and are injected as represented by arrow 4 into the trays of a carrousel circulating in the direction indicated by arrow 5 above a plurality of sorting outlets 6 of the machine.
Each tray normally transports a single postal item 2 to a sorting outlet 6 that is determined on the basis of automatically recognizing the postal address of the item by means of optical character recognition (OCR). Each postal item address corresponds to a distribution point in a delivery round and each distribution point is associated with a sorting outlet during a first or a second pass on the basis of a pre-established sorting plan as mentioned above.
At the end of the first pass, the postal items are returned to the inlet of the machine in a certain order (or sequence), e.g. by means of an automated system for handling tubs known as an automated tub management system (ATMS). With such a handling system, each sorting outlet is provided with a tub into which the postal items are loaded. In particular, at the end of the first pass, the tub is taken from the last sorting outlet of the machine and the postal items in the tub are reinserted into the machine in order to perform the second sorting pass. Then the tub is taken from the last-but-one sorting outlet of the machine and the postal items in that tub are subsequently reinserted into the machine, and so on until the items from the first sorting outlet of the machine have been reinserted. It will be understood that if N 1 sorting outlets are used during the first pass shared successively amongst the distribution points of the delivery rounds, the last sorting outlet has the rank “N1” and the first sorting outlet has the rank “1” in the succession of N 1 sorting outlets. Under such circumstances, if each distribution point is associated with the rank of the corresponding sorting outlet associated therewith during the first sorting pass and if during the second sorting pass the rank of the distribution point corresponding to each current postal item passing through the machine is read, it is possible to verify that the rank values for the successive postal items during the second sorting pass vary in a manner that is continuous, and in particular that decreases if it is considered that the rank of the last sorting outlet has a value that is greater than the rank of the first sorting outlet. Any sawtooth variation in the ranks, for example, is indicative of an error in the positioning of one or more postal items and thus of a sorting error in a delivery round that is detected by the method of the invention.
In FIG. 2 , there can be seen a series of consecutive postal items referenced A, B, C, . . . , L that have accumulated in the sorting machine 1 during a second pass, and the rectangle 10 represents an observation window covering a certain number of these accumulated postal items between points 7 and 8 of the carrousel 3 . In practice, the observation window 10 is a file 14 or table in a memory operating as a first-in-first-out (FIFO) stack in which there are recorded certain characteristics of these consecutive items, and from which rank is monitored in accordance with the invention.
In FIG. 2 , the arrow 11 represents the circulating movement of the postal items in the machine between the points 7 and 8 , and thus the direction in which the postal items accumulate in the observation window 10 . In the example of FIG. 2 , item A is no longer in the observation window, item B is the first item entered into the observation window (first in), and item K is the item that entered the observation window last. Below, the last item entered into the observation window 10 , i.e. the item that has just passed the insertion point 7 , is referred to as the “inserted item” 12 and the first item to enter into the observation window, and thus the item that is about to pass the “sanction” point 8 , is referred to as the “current item” 13 . For greater clarity, the inserted item 12 , in this case item K, and the current item 13 , in this case item B, are respectively emphasized in the observation window 10 in FIG. 2 by underlining and by being printed bold. The observation window 10 is shown as having only ten postal items, but it should be understood that in practice the observation window can be larger in size. The size of the observation window is variable as a function of the unstacker and it serves to view six to several hundreds of postal items.
In order to implement the method of the invention, the file or table 14 can record a certain amount of data, and in this example for each of the postal items B to K, the following are recorded: the distribution point 15 for each item as determined by OCR or by reading an identifier in order to perform sorting; the rank 16 of each item for monitoring rank; the logical destination 17 of each item corresponding to a second pass sorting outlet for putting it back into circulation; an identifier 18 of the postal item for tracking the item through the machine; and control data 19 indicative of a recycled or non-recycled state of the postal item. The logical destination 17 is an order number identifying the sorting outlet to which the postal item is to be directed during the second sorting pass. The identifier 18 of the postal item is generally derived from the identification bar codes applied to the postal items during the first pass.
FIG. 3 shows an example of how rank monitoring is performed in the method of the invention, and FIG. 4 is in the form of a table 50 summarizing example rank values, in this case N and N−1, for a sequence of postal items that might lead to an item being put back into circulation. In particular, in table 50 , “Sanction” column 51 indicates either normal sorting of the current item 13 : sanction=“OK”; rejection of the current item: sanction=“Reject”; or putting the current item back into circulation: sanction=“Recycle”, as appropriate. The rows referenced L 1 to L 9 in table 50 correspond to each cycle of rank monitoring and comprise the current rank value (column 52 ), and the rank values 16 of the postal items present in the observation window.
With reference to FIG. 3 , in step 31 , it is checked whether the value of the rank 16 of the current postal item 13 in the table 14 is equal to a previously-initialized current rank value, in which case the current item is sorted normally in a sort outlet (step 32 ). This corresponds to the situation in rows L 1 , L 2 , L 7 , L 8 , and L 9 in table 50 . If the rank 16 of the current postal item 13 is different from the current rank, then the method moves onto step 33 where it is verified whether the rank 16 of the current item 13 is equal to the current rank minus one. If not, the current item is rejected (step 34 ). Otherwise, in step 35 , it is verified whether there is a postal item in the observation window having a rank 16 that is equal to the current rank. If not, the current item 13 is sorted normally (step 32 ) and the value of the current rank is changed to the value of the rank of said current item (step 36 ). At this stage, the value of the current rank is thus decremented by one. Now, if in step 35 , an item in the observation window 10 has a rank 16 equal to the current rank, then the method moves on to step 37 during which it is verified whether there exists at least one item in the observation window 10 that has a rank 16 equal to the current rank minus one, and that has been inserted into the observation window after all of the items in the observation window 10 of rank 16 that is equal to the current rank. If not, the current item 13 is rejected (step 34 ). This situation corresponds to row L 3 in table 50 . Otherwise, the method moves on to step 38 during which it is verified whether the number of items in the observation window 10 of rank 16 equal to the current rank is less than a predetermined threshold S 1 and simultaneously whether the number of items in the observation window 10 of rank equal to the current rank minus one is greater than a predetermined threshold S 2 . The values S 1 and S 2 are adjustable parameters making it possible to ensure that items are put back into circulation as a function of the size of the observation window, the recycle time of an item, and the errors that are encountered the most frequently. Experience shows that using a value S 1 of six and a value S 2 of three makes it possible to remedy a large number of sorting errors. Briefly, if the number of items with the current rank exceeds S 1 , there remain too many current-rank items to be sorted for it to be possible to change the current rank, and if the number of items with the current rank minus one is less than S 2 , there are not enough items with the current rank minus one to decide to change the current rank. If step 38 leads to an affirmative response, then the current item is sorted normally (step 32 ) and the value of the current rank is updated in step 36 . Otherwise, the method moves onto step 39 during which it is verified whether the logical destination 17 of the current item 13 is blocked, i.e. whether there is an item in the observation window 10 of rank 16 equal to the current rank and having the same logical destination 17 as the current item 13 . If the logical destination 17 of the current item 13 is not blocked, then the current item is sorted normally in step 32 . Otherwise, when the logical destination 17 of the current item 13 is blocked, the current item is put back into circulation in step 40 through the machine. This situation corresponds to rows L 4 , L 5 , and L 6 in table 50 . When items are recirculated in this way, the sorting of the current item 13 is delayed. In practice, the current item can make a complete revolution round the carrousel and reappear subsequently in the observation window 10 , i.e. at a moment when the value of the current rank is equal to the value of its own rank. It will be understood that the postal item which makes a complete revolution round the carrousel of trays crosses its injection point in the carrousel of trays. Naturally, putting this postal item into recirculation must be followed by resynchronizing the injection of postal items into the trays of the carrousel, i.e. the presence of an item being recirculated in a tray means that a new item must not be injected into that tray and the new item that would have been injected into the tray is injected into the next available tray.
Clearly by way of indication, the carrousel of a sorting machine has 1000 trays organized as four independent virtual machines correspond to 250 trays for one revolution of the carrousel for each virtual machine, and each rank contains between 240 and 300 postal items. Consequently, when an item placed between items of lower rank is recycled, it is highly probable that it will pass through the sanction point again while it is surrounded by items having the same rank as itself.
Furthermore, it is known from the first sorting pass how many items there are that belong to each rank. It is therefore possible to verify whether it is useful to recycle an item by using the known number of items belonging to each rank in order to calculate the rank of the items between which this item will be located after making a complete revolution round the carrousel.
In general, steps 31 , 33 , and 35 serve to verify whether there is lack of coherence in the order that postal items go past, while steps 37 , 38 , and 39 consist in determining whether the current item needs to be rejected, sorted, or recycled through the machine in order to re-establish coherence in the sequence of second-pass items.
The control data 19 serves to avoid causing any one postal item to be recycled twice. In particular, if during the second pass of an (already recycled) postal item through rank monitoring it is still not possible to sort the item normally, then it is rejected.
The idea of putting back into circulation the current postal object after having made this current postal item perform a complete revolution of the carrousel can be implemented different ways, i.e. by using various criteria or conditions to decide the recirculation of an item.
FIG. 5 represents for example an other way to implement the method in accordance with the invention compare to the one described in reference to FIG. 3 . The sorting machine is arranged or programmed to perform automatically the different steps of the method in accordance with the invention and to decide and control the accomplishment of this various method steps according to the various circumstances. In step 31 of FIG. 5 , similar to step 31 of FIG. 3 , it is checked whether the rank 16 of the current postal item is equal to a previously-initialized current rank. If the rank of the current postal item is equal to the current rank, the current item is sorted normally in a sort outlet (step 32 ). If the rank of the current postal item is different from the current rank, it is checked in step 60 whether there is a postal item in the observation window having a rank equal to the current rank. If no postal item in the observation window presents the current rank, the current rank is changed at step 61 , i.e. that the current rank is decremented by one of said current item, and it is checked one more time at step 62 if the rank of the current postal item is equal to the new current rank. If yes, the current postal item is sorted at step 62 . If not, the process moves back to step 60 . The loop constituted by steps 60 , 61 and 62 is, for example, a way to have the current rank changed in order to perform the rank monitoring. The current rank varies according to the postal items present in the observation window. For sorting safety reason, the current rank might not be changed twice in row, i.e. the loop might not be traced twice. If at least one postal item in the observation window is of current rank, it is checked in step 63 if the rank of the current postal item is equal to the current rank minus one. In the affirmative, it is verified during step 64 whether the number of items in the observation window of rank equal to the current rank is less than a predetermined threshold S 1 ′ and simultaneously whether the number of items in the observation window of rank equal to the current rank minus one is greater than a predetermined threshold S 2 ′. The thresholds S 1 ′ and S 2 ′ correspond to the thresholds S 1 et S 2 of step 38 of FIG. 3 . In the affirmative, the current rank is decremented by one unit (step 61 ) and the current postal item is sorted. In the negative in step 64 , the recirculation of the current postal item is controlled in step 66 in the machine by making the current postal item perform a complete revolution of the carrousel. If the rank of the current postal item is different from the current rank minus one (step 63 ), it is checked in step 65 if the rank of the current postal item is lower than the current rank. If the rank of the current postal item is lower than the current rank, a recirculation is controlled for the current postal item, while if the rank of the current postal item is greater than the current rank, the current postal item is rejected in step 67 . A current postal item of rank greater than the current rank can not be restored in sequence through a recirculation because the items of the item sequence in which it should have been sorted have already been sorted.
In this way to implement the method in accordance with the invention, the postal items having a rank equal to the current rank minus one are distinguished from the postal items having a rank lower than this current rank minus one because a way is revealed (step 64 ) for sorting directly the postal items having a rank equal to the current rank minus one while minimizing the incidence on the throughput of the sorting machine. The way of implementing the method in accordance with the invention of FIG. 5 shows a close connection between the variation of the current rank and the criteria for deciding the control of a recirculation.
According further to an other way to implement the method in accordance with the invention, illustrated on FIG. 6 , all the current items having a rank lower than the current rank are considered the same way, i.e. are recirculated, and the variation of the current rank is decided independently of the process of decision for the sort of the postal items.
It is checked in step 31 of FIG. 6 , similar to step 31 of FIG. 3 or FIG. 5 , whether the rank of the current postal item is equal to a previously-decided current rank. If the rank of the current postal item is equal to the current rank, the current item is sorted normally in a sort outlet (step 32 ). If the rank of the current postal item is different from the current rank, it is checked in step 70 whether the rank of the current item is lower than the current rank. If the rank of the current item is lower than the current rank, a recirculation (step 71 ) of the current item is controlled and if the rank of the current item is greater than the current rank, a rejection (step 72 ) of the current item is controlled. The variation of the current rank is monitored independently from the detection of the difference relative to the predetermined expected sequence and of the practical criteria for deciding the recirculation of the current item. The variation of the current rank can be monitored and the current rank decremented for example by means of a simple loop similar to steps 60 - 62 of FIG. 5 or by using decision parameters more complexes referring for example to an observation of the observation window and the use of different thresholds. This current rank is determined before starting the method described with reference to FIG. 6 . Referring to FIG. 6 , any current item having a rank lower than the current rank is recirculated because this current item normally has to be sorted while being surrounded by postal items having the same rank than the current item has and that will consequently succeed the current item during this sorting pass. Then whatever the rank of the current item is, there is a probability for this current item to pass again, after one or several rotation in the carrousel, i.e. after having be delayed for sort, about the sanction point 8 for the rank monitoring while being surrounded by items of its rank.
Recirculating a current postal item consists in keeping it in the tray of the carrousel in which it lays while passing the tray above every sorting outlets without depositing the item and in presenting this item again always in the same tray in the observation window and about the point where the sanction to apply to this item, which become consequently again the current item, is decided. Consequently, when a current item is recirculated by making it performing a complete revolution of the carrousel, it is decided to sort a given number of consecutive items succeeding the current item, actually as many items as the number of trays of the carrousel, before taking a new decision relative to its sort. During a recirculation operation, the machine is controlled in order the current item performs a complete revolution in the carrousel so as to delay the deposit in an appropriate sorting outlet. Thus a current item, which has already performed a complete revolution in the carrousel succeeds in the sort to a sequence of postal items which was succeeding this item at the time of the rank error detection and of the control of the recirculation. The recirculation decision and the accomplishment of the recirculation is wholly automatic, the item does not leave the sorting machine et does not has to be reintroduced in the machine, it follows normally its path in the machine to be sorted after a given delay.
After a complete revolution of the carrousel of trays, or several revolutions if it is decided to permit several successive recirculation, the recirculated item can be replaced in the expected sequence and therefore be sorted. To verify that the item is indeed in the expected sequence, the rank monitoring is used, i.e. it is checked if the rank of the current item, when the recirculated item become again the current item, corresponds indeed to the current rank. In the above described examples, this rank monitoring, to verify that the obtained sequence after recirculation is correct, is done automatically and explicitly-because of the loop application of the method described for example with reference to FIGS. 3 and 5 to every postal items introduced in the observation window and therefore to the recirculated postal items.
An other implementation of the idea in accordance with the invention consists in automatically recirculating a postal object during a second sorting pass when this item can not be directly sorted, for example when an error in the expected sequence is detected or when the sorting outlet in which the postal item has to be deposited is not ready to receive an item at the time the item pass in the tray above the sorting outlet, for example because a tub replacement is taking place in the concerned sorting outlet, followed by a rank monitoring to verify that the recirculated item passing about the sanction point has a rank that corresponds to the current rank and therefore can, or can not, be sorted, or further can be recirculated again according to the criteria exposed previously for example with reference to FIGS. 3 , 5 and 6 . The combination recirculation followed by a rank monitoring can be used each time a sorting error has been detected.
The rank monitoring has then for purpose to verify if an item recirculated in the carrousel of trays can be sorted because it is effectively surrounded by items having the same rank than it has. Such a verification allows the user to take advantage of the recirculation possibilities given by a machine having a carrousel of trays during a second sorting pass, the recirculation possibilities being until now not compatible with the necessity to maintain unchanged the item sequence during this second sorting pass. | A method of processing postal items in a postal sorting machine for preparing delivery rounds in a plurality of sorting passes (typically two sorting passes) includes a step that is performed during a sorting pass and for each current item, said step consisting in monitoring ( 31, 33, 35, 37, 38, 39 ) data representative of an order number or rank allocated to the distribution point corresponding to the current postal item in a predetermined sequence of distribution points to be run through this sorting pass in order to prepare each delivery round, the monitoring consisting in observing how rank varies for successive postal items in order to detect any difference relative to said predetermined sequence. In response to detecting such a difference for a current item, said current item is put back into circulation through the machine in order to delay its sorting and thus recreate the expected sequence. | 8 |
RIGHTS OF THE GOVERNMENT
The invention described herein may be manufactured, used, and licensed by or for the Government for Governmental purposes without the payment to me of any royalties thereon.
BACKGROUND OF THE INVENTION
The invention relates generally to a method and apparatus for setting a time delay in a projectile fuze. More particularly, the invention relates to a method and apparatus for automatically setting a time delay in a digital type projectile fuze during the exit of the projectile from a gun barrel, wherein the time delay data is inductively transmitted from a transmitter secured to the barrel muzzle to a receiver located in the projectile.
The advent of terrain guidance missiles or low flying cruise type missiles has facilitated undetected penetration of outer defenses and greatly decreased the time between detection and target impact. Fast countermeasure response is also necessary under battle conditions such as an enemy helicopter rising from behind cover, sighting, firing, and descending behind cover before an air defense gun can respond properly and fire. Since these type threats can be considered "soft armored", the best countermeasure is often a high explosively fragmented projectile. The time response to these types of threats is so small that presetting a fuze prior to firing is impractical. Proximity type fuzes, which can be used for a fast response gun system, suffer in accuracy due to signal multi-path returns on low trajectory projectiles, especially when encountering targets over water.
U.S. Pat. No. 3,958,510, issued May 25, 1976 to Stutzle, describes a system for setting the fuze of a projectile as it leaves the muzzle of a gun by adjusting the magnitude of a magnetic field through which the projectile is passing. This system includes a control coil mounted on the muzzle of the gun barrel and a receiver coil mounted in the projectile. The amplitude of the induced current in the receiver coil which is generated during passage of the projectile through the control coil and which is used to set the fuze, is adjusted by adjusting the amplitude of a direct current supplied to the control coil. In this system, the amplitude of the induced voltage and receiver coil during passage through the control coil is dependent not only on the projectile velocity but also on the centering of the projectile within the control coil.
U.S. Pat. No. 4,142,442, issued Mar. 6, 1979 to Tuten, describes a system in which the time setting of the fuze of an artillery shell is digitally set after the shell has been fired but before it leaves the muzzle of the gun. The communications link for setting the fuze includes a transmitting coil mounted on the gun muzzle and a receiving coil mounted on the artillery shell. The transmitting coil is energized with a plurality of signals at discrete frequencies. The output from the receiving coil is detected to derive one binary digit representing each discrete frequency. All of the binary digits are simultaneously set into a binary counter in the fuze, so that the binary number represents the time delay setting for the fuze. This system requires a plurality of constant frequency oscillators in the transmitter, as well as a like plurality of filters tuned respectively to the frequencies of outputs of the oscillators.
U.S. Pat. No. 4,022,102, issued May 10, 1977 to Ettel, describes a much simpler system for adjusting a projectile fuze after firing a projectile out of a gun barrel, wherein information is transmitted inductively from a transmitter mounted in front of the gun barrel to a receiver located in the projectile. The passage of the projectile through a trigger coil mounted adjacent the barrel muzzle triggers the transmission of pertinent information and after such passage, information is computed and stored. Upon passage of the projectile through a transmitter coil disposed in front of and spaced from the trigger coil, the information is transmitted from the transmitter coil in the form of pulses to the receiver coil. The length of the transmitter coil and the frequency of the pulses are chosen so that all information can be transmitted during the time that the receiver coil is inductively coupled with the transmitter coil. These two spaced-apart coils mounted to the gun barrel are more difficult to shield against countermeasures signals and to protect against erosion by propellant gases than a single coil of very short length, such as described in my U.S. Pat. Nos. 4,228,397 and 4,486,710. Also, these two spaced-apart coils present a conspicuous target to enemy gun fire.
SUMMARY OF THE INVENTION
Therefore, it is a primary object of the invention to provide a method and apparatus for setting a time delay value in an electronic fuze of a projectile exiting the muzzle of a gun barrel, in which a single transmitter coil mounted to the gun muzzle is utilized both to sense the projectile and to inductively transmit a radio frequency signal having a duration proportional to the fuze time delay value to a receiver coil disposed in the projectile during the time period in which the transmitter and receiver coils are inductively coupled.
It is a further object of the invention to provide such a method and apparatus in which the input communications circuitry disposed in the projectile is disabled immediately after muzzle exit.
It is another object of the invention to provide such a method and apparatus in which the transmitter coil is effectively shielded against any electronic countermeasure signals.
It is a still further object of the invention to provide such a method and apparatus in which the transmitter coil is designed and constructed to minimize erosion of the coil by propellant gases expelled from the gun barrel.
In the method and apparatus described herein, a transmitter coil mounted on the gun muzzle is energized from a radio frequency oscillator before the projectile is fired. As the projectile begins to emerge from the muzzle of the gun, its presence is detected by a change in the impedance in the transmitter coil. The presence of the projectile at the muzzle automatically switches the oscillator to a wait period while the projectile passes through the muzzle-mounted transmitter coil until the receiving antenna on the projectile is aligned with the transmitter coil. At this time, the oscillator is turned back on in a data communicating mode. Calculated time of flight (TOF) data from a fire control system is then transmitted to the projectile in a pulse packet mode. This TOF data is coupled into a digital time delay circuit in the projectile which translates the received signal into the actual time delay required to detonate the projectile at target engagement. Also, electronic circuitry in the projectile automatically disables the input circuitry to the projectile immediately after completion of the data transfer to eliminate any possibility of enemy electronic countermeasures.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will be better understood, and further objects, features and advantages thereof will become more apparent from the following description of the preferred embodiment, taken in conjunction with the accompanying drawings in which:
FIG. 1 is a view, in perspective, of a projectile exiting a gun muzzle through a radio frequency transmitter coil, according to the invention;
FIG. 2 is a block diagram of the projectile sensing and data transmitting circuitry, according to the invention;
FIG. 3 is a plot of amplitude versus time for various signals in the sensor and transmitter circuits, during the time that the projectile is exiting the gun muzzle;
FIG. 4 is a block diagram of the RF receiver circuit in the projectile, according to the invention; and
FIG. 5 is a plot of amplitude versus time for various signals in the RF receiver, during and after the exit of the projectile from the gun muzzle.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The basic mechanics of the data transmission method is shown in FIG. 1. A transmitter coil 10, which also serves as a sensor loop, is rigidly attached to the muzzle face 12 of a gun tube 14. The transmitter coil 10 is held in place by a mounting collar of electrially-conductive material, not shown in this figure for clarity. The mounting collar may be screwed onto the gun, clamped to the gun, or bolted to the muzzle face depending on the gun configuration. For example, this mounting collar may be similar to that described in my U.S. Pat. No. 4,228,397, incorporated herein by reference, in which a conductive tube member disposed about the end of the gun muzzle has an inwardly projecting shoulder which extends over and shields the coil 10. This mounting flange limits the RF radiation from the transmitter coil 10, to minimize detection of this field by enemy observers. Also, the mounting collar shields the transmitter coil 10 against enemy countermeasure signals.
The transmitter coil 10 is configured to have a narrow width, to minimize the area of the coil exposed to the severe environment at the muzzle end of the gun barrel 14. For example, if more than a single turn is utilized in this transmitter coil 10, the coil can be wound as a "pancake" coil to maintain minimum thickness. Preferably, the transmitter coil 10 is a ceramic coated coil, similar to that described in my U.S. Pat. No. 4,524,323, which is incorporated herein by reference. The use of such a ceramic coated coil greatly reduces the rate of erosion of the inner loop of the coil when it is attached to the muzzle face of the gun barrel 14.
The transmitter coil 10 and a tuning capacitor 16, which is connected across the transmitter coil 10 and which is mounted in the collar or in a small box attached to the collar, is connected to an RF oscillator 18 by a cable 20. When excited by the oscillator 18, the transmitter coil 10 radiates an electromagnetic field into the bore area of the gun barrel 14. As the bourrelet 22 of a projectile 24 passes the transmitter coil 10, interaction between the projectile 24 and the electromagnetic field causes an impedance change in the oscillator signal which, when electronically processed, indicates the presence of the projectile 24 at the transmitter coil 10. Through the use of electronic circuitry and electronic time delays, the oscillator signal is disconnected from the transmitter coil 10 for a predetermined time based on the projectile dimensions and projectile muzzle velocity. During this time the projectile continues to emerge from the gun barrel 14.
After a period of time, sufficient to allow a section of the projectile containing a receiver coil 26 to slightly pass the transmitter coil 10, the time of flight data is inductively transmitted to the projectile 24 via the receiving coil 26 which is insulated from the metallic part of the projectile 24. This is done by turning the oscillator 18 back on in a short burst, the time duration of which is determined by the time of flight desired. The burst of data transmitted to the projectile 24 is then coupled to signal processing circuitry within the projectile 24.
In FIG. 1, the receiver coil 26 is shown as a relatively small coil extending along one side of the projectile 24 which is insulated from the projectile by a layer 28 of insulating material. For optimum inductive coupling of the transmitter and receiver coils, the receiver coil 26 could be formed as a coil of insulated conductive tape or wire extending completely about the main body of the projectile 24. However, such a large receiver coil would be very subject to mechanical damage during firing. Conversely, if the receiver coil were formed as a rigid receiver bus extending along one side of the projectile 24, it could be more easily protected against mechanical damage during firing but would have minimal inductive coupling with the transmitter coil, thus requiring more stages of amplification in the signal processing circuitry of the projectile 24. The particular configuration shown in FIG. 1 for the receiver coil 26 represents a compromise between the desired electrical and mechanical characteristics of this coil.
The block diagram of the electronic circuitry for sensing the presence of a projectile 24 at the gun muzzle and for transmitting the required data to the projectile 24 are shown in FIG. 2, and the associated timing waveforms are shown in FIG. 3.
When a projectile 24 is fired through the gun barrel 14, the crystal controlled oscillator 18 is normally oscillating and providing a 10 MHz output signal 30 through an electronic switching circuit 32 to the transmitter coil 10. A Connor-Winfield Corp. amplifier, Model S14R2, may be used for the oscillator 18, and an RCA integrated circuit switch CD-4066 may be used for the oscillator switch 32. A 10 MHz frequency is used here for purposes of explaining the circuit operation. However, other frequencies can be used, as will be explained later. The oscillator 18 also provides a 10 MHz clock signal 34 to a programmable counter 36, such as an RCA counter CD-4059.
The 10 MHz signal 30 to the transmitter coil 10 excites the transmitter coil 10, providing a means of detecting the presence of the projectile 24 at the gun muzzle 12. As the presence of the projectile 24 interacts with the radiated field of the transmitter coil 10, the amplitude of the oscillator signal 30 across the transmitter coil 10 is modulated. The oscillator signal 30 is amplitude detected by a conventional diode detector 38, which provides a positive going output signal 40 to the input of an amplifier 42, such as a Harris HA-2625 amplifier. The amplified signal 44 is feed to voltage comparator 46, for example, a Motorola MC-1710, which provides a transistor-transistor logic (TTL) pulse 48 to a "DELAY" multivibrator 50, causing the "DELAY" multivibrator 50 to generate a positive output pulse 52 for a preset delay time. The negative-going trailing edge of the output signal 52 of the "DELAY" multivibrator 50 triggers a "WAIT" multivibrator 54.
The "WAIT" multivibrator 54 has a Q output which normally supplies a positive output signal 56 to one input 58 of an "OR" gate 60, such as one gate of an RCA CD-4001 gate assembly. In turn, the "OR" gate 60 supplies a positive output signal 62 to the oscillator switch 32 to maintain the oscillator switch 32 closed. When the "WAIT" multivibrator 54 is triggered by the negative-going edge of the "DELAY" multivibrator output signal 52, the Q output of the "WAIT" multivibrator 54 is opened and the Q output signal 56 drops to zero for a preset period of time. When the Q output signal 56 drops to zero, the output signal 62 of the "OR" gate also drops to zero, causing the oscillator switch 32 to open.
The "WAIT" multivibrator 54 also has a normally open Q output connected to the input of the comparator 46. When the "WAIT" multivibrator 54 is triggered by the negative-going edge of the "DELAY" multivibrator output signal 52, a positive output signal 64 is generated at the Q output for the same predetermined period of time as the Q output is opened. This positive output signal 64 is fed back to the input of the comparator 46 as positive feedback to hold the comparator output high when the oscillator signal 30 is switched off. The delay introduced by the "DELAY" multivibrator 50 is necessary to prevent the circuitry from trying to cut off the oscillator signal 30 at the precise instant the presence of the projectile 24 is being detected.
The negative-going trailing edge of the output signal 52 of the "DELAY" multivibrator 50 is also used to trigger a "REQUEST DELAY" multivibrator 66, which generates a positive output signal 68 for a predetermined time delay period. The time delay provided by the "REQUEST DELAY" multivibrator 66 is such as to allow the receiver coil 26 on the projectile 24 to slightly pass the transmitter coil 10. This time delay is based on the projectile dimensions, the muzzle velocity and the normal variations in velocity to ensure that the receiver coil 26 is in proper position to receive the data transmitted from the transmitter coil 10.
The trailing edge of the output signal 68 of the "REQUEST DELAY" multivibrator 66 triggers a "REQUEST DATA" multivibrator 70, which generates a positive output pulse 72. The leading edge of the "REQUEST DATA" multivibrator output signal 72 is used to request data transfer from a fire control system 74.
The fire control system 74, which is not part of the present invention, can be a radar tracking system or laser range finder system which tracks a target and provides an estimate of the time of flight of the time of the projectile to the predicted target position.
In response to the data request signal 72, the fire control system 74 provides an estimated time of flight signal 76 in binary-coded decimal (BCD) format to the programmable counter 36. The fire control system 74 also provides a TTL positive pulse 78 indicating data transfer to trigger an "ENABLE DELAY" multivibrator 80, which generates a positive output pulse 82. The negative-going trailing edge of the output pulse 82 of the "ENABLE DELAY" multivibrator 80 triggers a "DATA" multivibrator 84.
The Q output signal 86 of the "DATA" multivibrator 84 is supplied to the other input 88 of the "OR" gate 60. When the "DATA" multivibrator 84 is triggered its Q output signal 86 goes positive, causing the output signal 62 of the "OR" gate 60 to go positive and turn on the oscillator switch 32. When the oscillator switch 32 turns on, it couples the 10 MHz oscillator signal 30 to the transmitter coil 10 to transmit data to the projectile 24.
The Q output signal 90 (complement of the Q output signal 86) of the "DATA" multivibrator 84 is supplied to an inverter 92, such as an RCA CD-4049 converter. The inverted output signal 94 from the inverter 92 is supplied to the K B input of the programmable counter 36 to switch this counter from the "preset" mode to the "count" mode. At this time the clock pulses 34 are counted by the programmable counter 36.
When the clock pulses counted reach the number 76 for the time of flight, the programmable counter 36 outputs a pulse 96. This pulse 96 triggers a "RESET" multivibrator 98. The output signal 100 of the "RESET" multivibrator 98 resets the output of the "DATA" multivibrator 84 to zero. This terminates the Q output signal 88 of the "DATA" multivibrator 84, which opens the oscillator switch 32 discontinuing the transmission of the 10 MHz signal 30 to the projectile 24. Thus, the number of 10 MHz cycles transmitted to the projectile 24 equals the time of flight number 76 entered into the programmable counter 36. The resetting of the "DATA" multivibrator 84 also switches the programmable counter 36 back to the "preset" mode so that the system is ready for the next round fired.
The delay introduced by the "ENABLE DELAY" multivibrator 80 is to assure the BCD time of flight data 76 is entered before the programmable counter 36 is permitted to start counting. This delay only needs to be several microseconds and simply means that the projectile receiver coil 26 passes the transmitter coil 10 a little further than necessary, but in no way affects the data transfer.
Commercially available devices may be used for any of the electronic elements in the sensor and data transmission system of FIG. 2. For example, RCA CD4098 dual monostable multivibrators may be used for the multivibrators 50, 54, 66, 70, 80, 84, and 98.
The block diagram of the timing circuit of the fuze in the projectile 24 is shown in FIG. 4, and the waveforms associated with this block diagram are shown in FIG. 5.
The 10 MHz data burst 110 is picked up by the receiver coil 26 as the projectile 24 passes through the transmitter coil 10. A 10 MHz amplifier 112, such as an Aventec GPD-202 or a Signetic NE-5205D, amplifies this signal 110. The amplifier output signal 114 is coupled into a voltage comparator 116, such as a Motorola MC-1710. The output of the comparator 116 is TTL level pulses 118 at a 10 MHz. rate. This burst of pulses 118 is coupled to a three decade (more if necessary) counter circuit 120, 122, and 124, which may be three RCA CD-4029 up/down counters. The output signals 126, 128, and 130 of the counters 120, 122, and 124, respectively, are coupled in BCD format into a programmable counter 132, such as an RCA CD-4059 counter, as the pulses are counted.
The output signal 118 of the comparator 116 also triggers a "(TOF) ENABLE DELAY" multivibrator 134. The "TOF ENABLE DELAY" multivibrator 134 is a re-triggable multivibrator having a pulse duration which is set to be 5 to 10 times the time duration (0.1 microseconds) of the 10 MHz comparator output signal 118. When triggered by the first pulse, the multivibrator 134 would normally time out after its timed condition of 0.5 to 1.0 microseconds; however, a succeeding 10 MHz pulse re-triggers the multivibrator 134 so that the pulse duration is equal to the time duration of the 10 MHz burst 118 plus the preset time of 0.5 to 1.0 microseconds.
The negative-going trailing edge of the output signal 136 of the "TOF ENABLE DELAY" multivibrator 134 triggers a "TOF ENABLE" multivibrator 138. The output signal 140 of the "TOF ENABLE" multivibrator 138 is fed to the K B input of the programmable counter 132, which switches the counter 132 from a "preset" mode to a "count" mode. The re-triggable multivibrator circuit 134 is used to assure that the TOF data in BCD form is entered in the programmable counter 132 before switching the counter to the "count" mode.
When switched to the "count" mode, the programmable counter 132 begins counting clock pulses 142 derived from a 1 KHz. oscillator 144, such as a Conner-Winfield S15R5, or the 1 KHz. pulse rate divided by a divider 146 such as an RCA CD-4029 up/down counter. The selection of the clock frequency is dependent on the maximum time of flight desired and the accuracy required, as is discussed below.
When the number of pulses counted by the programmable counter 132 equals the time of flight number entered in BCD form, the programmable counter 132 outputs a pulse 150 which is coupled to a fuze detonator circuit 152, which, in turn, detonates the explosive charge in the projectile warhead.
The negative-going edge of the output signal 136 of the "TOF ENABLE DELAY" multivibrator 134 is also used to trigger an "ANTI-JAM" multivibrator 154. The output signal 156 of this multivibrator 154 is fed back to the input of the voltage comparator 116 to disable it. Thereafter, if a countermeasure signal was being transmitted to "jam" the electronics of the fuze, the comparator 116 being disabled blocks entry of this jamming signal into the counter circuits 120, 122, 124.
RCA CD-4098 dual monostable multivibrators may be used for the multivibrators 134, 138, and 154.
To explain the operation of the invention described herein, consider a case where an intruder is not detected until the last moment and the time of flight of the projectile was calculated by the fire control 74 to be 0.520 seconds. The BCD number entered into the programmable counter 36 would be entered as 520. This would cause a burst of 520 cycles of the 10 MHz signal to be transmitted to the projectile. Thus the time duration of the data transfer would be 52 microseconds. The 520 cycles transferred to the projectile would be counted and entered as the number 520 in BCD form into the programmable counter 132 in the projectile. If the clock rate in the projectile was 1 KHz, the programmable counter 132 would then count 520 pulses with a time interval between pulses of one millisecond. Therefore, when 520 pulses were counted the delay before detonating the warhead would be 520 milliseconds, or 0.52 seconds.
The maximum time of the data transfer window depends upon the projectile velocity and the receiver coil length. This limits the maximum number of 10 MHz pulses which can be transmitted to the projectile and, therefore, the maximum delay.
Assuming a typical projectile velocity of 3000 ft/sec and the time of resolution of the delay to be ±1.0 millisecond, the accuracy could be ± three feet at a range of 3000 feet. This does not take into account total system errors caused by the electronics. However, for a typical small caliber projectile, for example, for a caliber of 40-mm, the total projectile length may be in the order of seven inches. On a projectile of this size, the receiver coil could be on the order of two and a half inches long. Allowing one quarter of an inch on each end of the receiver coil to account for position variation due to projectile velocity variation, the receiving coil would be in position for two inches of projectile travel. This limits the maximum communication window to 56 milliseconds or 560 pulses which results in a maximum time delay of 0.56 seconds when using a 1 KHz clock in the projectile. Normally, a longer maximum delay is required.
There are several methods which could be used to increase the maximum time of flight delay. For example, one method would be to raise the 10 MHz. oscillator frequency to 20 MHz. This would double the number of pulses transmitted to the projectile, resulting in a maximum of 1040 pulses being counted at a 1 KHz rate or a maximum time of flight of 1.040 seconds.
Another method would be to divide the 1 KHz clock frequency on the projectile by some factor, which could be done by the divider 146 in the circuit of FIG. 4. For example, dividing the 1 KHz by two would result in a time duration between the pulses counted of two milliseconds or a maximum time of flight of 1.040 seconds. To maintain coherence between the computed time of flight entered into the data transmission circuit and the fuze timing, the time of flight computed would be divided by two before entering it into the programmable counter 36.
Using a 10 MHz oscillator frequency and a 1 KHz clock frequency on the projectile, the following maximum delays and accuracy based on the clocks for a projectile as described would result:
______________________________________ Resolution atMaximum Time Delay Divide by: 3000 feet (range)______________________________________0.56 seconds 1 3 ft.1.12 seconds 2 6 ft.2.8 seconds 5 15 ft.5.6 seconds 10 30 ft.______________________________________
The examples given herein are general in nature and the choice of the oscillator frequency and the clock division ratio would depend upon this specific system desired, taking into account the projectile's size, velocity and practical target engagement range.
There are many variations, additions, and changes to the invention which would be obvious to one skilled in the art. For example, rather than automatically reactivating the transmitter coil 10 after the projectile has left the gun muzzle, the transmitter coil could be reactivated either manually or automatically at the time the next projectile was fired. Therefore, it is intended that the scope of the invention be limited only by the appended claims. | A method and apparatus for setting a time delay value in an electronic fuze of a projectile exiting the muzzle of a gun barrel, in which a single transmitter coil concentrically mounted to the gun muzzle is utilized both to sense the presence of the projectile at the gun muzzle and to inductively transmit a radio frequency signal having a duration proportional to the fuze time delay value to a receiver coil disposed on the projectile. The transmitter coil is energized from a radio frequency oscillator before the projectile is fired. As the front end of the projectile begins to emerge from the gun muzzle, its presence is detected by a change in the transmitter coil impedance, and the transmitter coil is automatically deenergized. The receiver coil is spaced from the front end of the projectile so that it is not inductively coupled to the transmitter coil, the transmitter coil is reenergized from the oscillator for a time period proportional to the fuze time delay value to be set, then again deenergized until the projectile has completely emerged from the gun muzzle. The signal received by the receiver coil is processed by circuitry within the projectile to set the fuze time delay value. | 5 |
FIELD OF THE INVENTION
The present invention relates to a solar cell and a production method therefor and, more particularly, to solar cells for easy and precise serial connection.
BACKGROUND OF THE INVENTION
FIG. 14 shows a prior art solar cell which is disclosed in "Solar Photovoltaic Power Generation" by Kiyoshi Takahashi, Yoshihiro Hamakawa, and Akio Ushirokawa, Morikita Shuppan, 1980, pages 147, 322, and 323. As shown in the figure, an n + layer 2 is disposed at a first surface of a p-type silicon substrate 1, and a collection electrode 4 is disposed on the n + layer 2. The collection electrode 4 includes an external connection bus electrode 4a and comb-type bar electrodes 4b and functions as a negative electrode. Where the collection electrode 4 on the n + layer 2 is absent, a reflection preventing film 3 is disposed. A plane electrode 5, which functions as a plus side electrode, is disposed on the other surface of the p-type silicon substrate 1.
FIG. 15 shows a solar cell module in which the solar cells 10 as described above are connected serially and in parallel to generate higher power. As shown in the figure, the collection electrode 4 (bus electrode 4a) of one of the two adjacent solar cells 10 is connected with the planar electrode 5 of the other of the cells 10 via a metal foil 6 several tens of microns thick.
A silver foil is usually used as the metal foil 6 and is bent at two location as shown in FIG. 15. One end of the metal foil 6 is welded or soldered to the bus electrode 4a of the collection electrode 4 of the respective solar cells 10. Next, the solar cells 10, having the metal foil 6 connected with the bus electrodes 4a, are arranged upside-down. Thereafter, the free end of each of the metal foils 6 is welded or soldered to the planar electrodes 5 of the adjacent solar cells.
The solar cells 10 connected in series by metal foils 6 are encapsulated in a transparent water-proof resin 7 and the transparent water-proof resin 7 is disposed between glass plates 8. Finally, in an environment where the intrusion of air is prevented, the device is heated above the softening point of the resin so that the solar cells 10, the transparent water-proof resin 7, and the glass plates 8 are adhered. Then, edges of the adhered device are mounted in a metal frame 9, thereby completing a solar cell module.
In such a prior art solar cell, the collection electrode 4 at the surface of one of the adjacent solar cells and the plane electrode 5 at the rear surface of the other of the adjacent solar cells have to be connected by the metal foil 6. The connection process using the metal foil 6 is troublesome because the foil has to be connected at both the front and rear surfaces of the solar cells. Since the collection electrode 4 projects from the front surface, when the metal foil 6 is bonded onto the planar electrode 5 (the respective solar cells are then upside-down), the respective solar cells 20 are unstable. The solar cells are then supported only by the collection electrode 4, thereby making it impossible to apply sufficient force for bonding the metal foil 6 onto the planar electrodes 5.
SUMMARY OF THE INVENTION
An object of the present invention is to provide a solar cell and a production method therefor for easy and precise serial connection of solar cells.
Other objects and advantages of the present invention will become apparent from the detailed description given hereinafter. It should be understood, however, that the detailed description and specific embodiments are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent from the detailed description.
According to an aspect of the present invention, a solar cell includes a first conductivity type semiconductor substrate, a second conductivity type semiconductor layer disposed at a first surface of the semiconductor substrate, a first electrode disposed on the semiconductor layer, a second electrode disposed on a second surface of the semiconductor substrate, a connection electrode disposed on the first surface of the semiconductor substrate insulated from the semiconductor layer, and an electrical conductor electrically connecting the second electrode and the connection electrode along the thickness direction of the semiconductor substrate.
According to another aspect of the present invention, a fabrication method of a solar cell includes preparing a first conductivity type semiconductor substrate, producing a second conductivity type semiconductor layer on a first surface of the semiconductor substrate, depositing a first electrode on the semiconductor layer, producing an electrically conductive layer in the thickness direction of the semiconductor substrate, depositing a connection electrode electrically connected with the conductive layer and insulated from the semiconductor layer on the first surface of the semiconductor substrate at a position isolated from the semiconductor layer, and depositing a second electrode electrically connected with the conductive layer at a second surface of the semiconductor substrate.
In the present invention, since the first electrode and the connection electrode of the solar cell are both disposed on the first surface of the semiconductor substrate, the connection between the first electrode and the connection electrode of the different solar cells can be completed at one surface of each of the cells.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view showing a solar cell according to a first embodiment of the present invention;
FIG. 2 is a cross-sectional view taken along line I--I of the solar cell shown in FIG. 1;
FIGS. 3(a) to 3(g) are cross-sectional views illustrating a fabrication method for a solar cell according to the first embodiment;
FIG. 4 is a diagram showing the manner of connection of solar cells according to the first embodiment;
FIG. 5 is a perspective view showing a solar cell according to a second embodiment of the present invention;
FIG. 6 is a cross-sectional view taken along line II--II of the solar cell shown in FIG. 5;
FIGS. 7(a) to 7(g) are cross-sectional views illustrating a fabrication method for a solar cell according to the second embodiment;
FIG. 8 is a diagram showing the manner of connection of solar cells according to the second embodiment;
FIG. 9 is a perspective view showing a solar cell according to a third embodiment of the present invention;
FIG. 10 is a cross-sectional view taken along line III--III of the solar cell shown in FIG. 6;
FIGS. 11(a) to 11(h) are cross-sectional views illustrating a fabrication method for a solar cell according to the third embodiment;
FIG. 12 is a diagram showing the manner of connection of solar cells according to the third embodiment;
FIG. 13 is a top view showing a fabrication method of a solar cell according to the second embodiment;
14 is a perspective view showing a prior art solar cell; and
FIG. 15 is a cross-sectional view showing a prior art solar cell module.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 shows a solar cell according to a first embodiment of the present invention and FIG. 2 shows a cross-sectional view taken along line I--I of FIG. 1.
As shown in FIGS. 1 and 2, a connection electrode 11 is disposed at a location on the surface of the p-type silicon substrate 1 where the n + layer 2 is absent and is separated from n + layer 2. The connection electrode 11 is electrically connected with the planar electrode 5 disposed on the rear surface of the p-type silicon substrate 1 via an electrically conducting penetrating via 12. The via 12 comprises a hole metallized on its surface or throughout its volume. The same elements of FIG. 1 already described for the prior art device are not described again.
FIGS. 3(a) to 3(g) show a method for producing the solar cell 21 according to the first embodiment.
As shown in FIG. 3(a), an n + layer 2 is formed in the p-type silicon substrate 1 and a reflection preventing film 3 is formed on the n + layer 2. Next, as shown in FIG. 3(b), portions of the n + layer 2 and the reflection preventing film 3 are removed by etching, and a portion la of the surface of the p-type silicon substrate 1 is exposed.
An aperture 13 having a depth corresponding to a desired substrate thickness, that is, the substrate thickness which is to remain, is produced as shown in FIG. 3(c). Thereafter, a region of the reflection preventing film 3 distant from aperture 13 is removed, for example, by etching. This region where the film is removed is used for forming an electrode. A collection electrode 4 is deposited on the electrode production region of the n + layer 2 and on parts of the reflection preventing film 3. Further, a metallic grounding layer 14 is deposited by sputtering or vapor deposition on the bottom surface and side surfaces of the aperture 13 of the exposed portion 1a, as shown in FIG. 3(d).
The entire aperture 13 is filled with metal, thereby producing a via 12, as shown in FIG. 3(e), including a connection electrode 11 on the exposed portion 1a communicating with the via 12. Herein, sputtering or vapor deposition may be used for production of the connection electrode 11.
The p-type silicon substrate is polished from the rear surface, for example, by etching, and, as shown in FIG. 3(f), the grounding layer 14 is exposed from the rear surface of the p-type silicon substrate 1. Finally, a plane electrode 5 electrically connected with the grounding layer 14 at the rear surface of the p-type silicon substrate 1 is deposited, thereby completing a solar cell 21.
FIG. 4 shows the manner of serial connection of the solar cell 21 of the first embodiment. In FIG. 4, reference numeral I5 designates a mutual connection piece comprising a metal ribbon or solder.
As shown in FIG. 4, a mutual connection piece 15 is arranged over the bus electrode 4a of one of two adjacent solar cells 21 and extends to the connection electrode 11 of the other of the adjacent solar cells. The mutual connection pieces 15 are welded or soldered to those electrodes. The connection electrode 11 produced at one surface of the cell is electrically connected to the planar electrodes 5 tnrough the via 12 so that the serial connection of the adjacent solar cells by the mutual connection pieces 15 is accomplished solely at the surface of the p-type silicon substrate 1. Therefore, the solar cells 21 can be serially connected stably with the planar electrode 5 positioned at the bottom side.
As a result, the connection process is significantly simplified. Furthermore, since the unstable connection process where the solar cells 21 are upside-down and only supported by collection electrodes 4 is avoided, there are no problems of peeling or cracking at the connections, thereby enhancing reliability. Since the end portions of the plane electrodes 5 at the side opposite the connection electrode 11 are removed, the planar electrodes 5 of the adjacent solar cells are not short-oirouited by the serial connection process.
FIG. 5 shows a solar cell 22 according to a second embodiment of the present invention. FIG. 6 shows a crosssection taken along line II--II of FIG. 5. As shown in FIGS. 5 and 6, a connection electrode 16 is disposed over a side surface at one side of the p-type silicon substrate 1 to the exposed portion 1a. This connection electrode 16 is electrically connected to the planar electrode 5 and is produced independently from the n + layer 2. The portion of the connection electrode 16 on the side surface of the p-type silicon substrate 1 electrically connects the connection electrode 16 on the exposed portion la of the p-type silicon substrate 1 with the planar electrode 5 as the via 12 of the first embodiment did.
FIGS. 7(a) to 7(g) show cross-sectional views illustrating a fabrication method of a second embodiment in which a plurality of solar cells are produced at the same time. FIG. 13 shows a top view of the process and, for simplicity of explanation, only the collection electrode 4 (4a, 4b) and the cutting line 1 are shown.
As shown in FIG. 7(a), an n + layer 2 is formed at the surface of a p-type silicon substrate 1 and a reflection preventing film 3 is deposited on the n + layer 2. Next, portions of the n + layer 2 and the reflection preventing film 3 are removed by etching to expose a portion la of the surface of the p-type silicon substrate 1, as shown in FIG. 7(b). Thereafter, a region of the reflection preventing film 3 is removed, for example, by etching, thereby producing an electrode production region distant from portion 1a. A collection electrode 4 is deposited on the electrode production region of the n + layer 2 and on parts of the reflection preventing film 3, as shown in FIG. 7(c). FIG. 7(c) corresponds to the crosssection taken along line IV--IV of FIG. 13.
Subsequently, a groove 13a of a depth corresponding to a desired substrate thickness is produced by etching from the exposed portion la of the p-type silicon substrate 1, as shown in FIG. 7(d). A metallic grounding layer is deposited by sputtering or vapor deposition covering the bottom surface and the side surface of the groove 13a up to the exposed portion 1a. Thereafter, an electrically conducting layer 18 is deposited, as shown in FIG. 7(e). The conducting layer 18 itself may be produced by vapor deposition or sputtering.
Thereafter, a p-type silicon substrate 1 is polished from the rear surface by, for example, etching, thereby exposing the conducting layer 18 from the rear surface of the p-type silicon substrate 1 and, as shown in FIG. 3(f), a planar electrode 5 is produced at the rear surface of the p-type silicon substrate 1 electrically connected with the conducting layer 18. Herein, because the collection electrode 4 is deposited on a film, the p-type silicon substrate 1 is not deflected by the polishing. Finally, as shown in FIG. 7(g), the substrate is broken at portions 17a and 17b (refer to cutting lines of FIG. 13), and solar cells 22 having a connection electrode 16 derived from the conducting layer 18 are produced.
FIG. 8 is a diagram explaining the manner of connection of the solar cells 22. As shown in FIG. 8, because the connection electrode 16, which is electrically connected to the planar electrode 5, is produced extending up to the front surface, serial connection between the different solar cells using the mutual connection pieces 15 can be completed using only the top surface of the p-type silicon substrate 1, and the solar cells can be installed stably with the planar electrodes 5 at the bottom side.
As a result, similar to the solar cell of the first embodiment, the connection process is simplified and the reliability of the connections is enhanced, Similar to the first embodiment, since the ends of the planar electrode 5 at the side opposite the connection electrode 11 are removed, the planar electrodes 5 of adjacent solar cells will not short-circuit.
FIG. 9 shows a perspective view of a solar cell 23, a third embodiment of the present invention, and FIG. 10 is a cross-sectional view taken along line III--III of FIG. 9.
As shown in FIGS. 9 and 10, in addition to the construction of the solar cell 22 according to the second embodiment, a solder electrode 19 is disposed over a side surface of the p-type silicon substrate 1 at the side opposite the connection electrode 16 to a portion of the bus electrode 4a. This solder electrode 19 is electrically connected with the bus electrode 4a, and it is insulated from the p-type silicon substrate 1, the n + layer 2, and the reflection preventing film by an insulating film 20.
FIGS. 11(a) to 11(h) show cross-sectional views for explaining a production method of a solar cell device according to a third embodiment of the present invention in which a plurality of solar cells 22 are connected with each other similarly as in the second embodiment.
As shown in FIG. 11(a), an n + layer 2 is formed at the surface of a silicon substrate 1 and a reflection preventing film 3 is deposited on the n + layer 2. Next, portions of the n + layer 2 and the reflection preventing film 3 are removed by etching, thereby exposing a portion 1a of the surface of the p-type silicon substrate 1, as shown in FIG. 11(b). Thereafter, a predetermined region of the reflection preventing film 3 is removed, for example, by etching, thereby producing an electrode production region except at a region 1a. A collection electrode 4 is formed at this electrode production region of the n + layer 2, as shown in FIG. 11(c).
Next, a groove 13b is produced at an exposed portion 2a and, as shown in FIG. 11(d), an insulating film 20 is deposited over the bottom surface and on the side surfaces of the cutting groove 13b and on a portion of the collection electrode 4. Thereafter, a groove 13a is produced at the exposed region 1a, as shown in FIG. 11(e).
As shown in FIG. 11(f), a metallic grounding layer 18 is produced by sputtering or vapor deposition over the bottom surface and side surfaces of the groove 13a on a portion of the exposed region 1a An electrically conducting layer 24 is similarly deposited on a portion of insulating film 20 and the collection electrode 4. The conducting layers 18 and 24 themselves may be produced by vapor deposition or sputtering.
Thereafter, the rear surface of the p-type silicon substrate 1 is polished, for example, by etching, thereby exposing the conducting layer 18 at the rear surface. As shown in FIG. 11(g), a planar electrode 5 is produced at the rear surface of the p-type silicon substrate 1 electrically connected with the conducting layer 18. Finally, as shown in FIG. 11(h), the substrate is broken at portions 25a and 25b, thereby producing solar cells 23 having connection electrodes 16 produced from the layer 18 and the solder electrodes 19 produced from the layer 24.
FIG. 12 shows the manner of connection of solar cells 23. As shown in FIG. 12, solar cells are arranged adjacent to and contacting each other and heated to a temperature above the melting point ofthe solder, to about 140 to 150° C. The solder electrode 19 and the connection electrode 16 are connected by soldering without requiring the mutual connection pieces 15 as in solar cells 21 and 22.
Because electrode connections are made without using mutual connection pieces 15, the production process of the solar cell module is simpler than that for the solar cells 21 and 22. Further, since the electrode connections are made only by heating, the mechanical stresses applied to the solar cells 23 during the connection of electrodes are almost eliminated and solar cells having much higher reliability are obtained. The same effects can also be obtained by using mutual connection pieces 15 made of solder by arranging the mutual connection pieces on the bus electrode 4a and the connection electrode 11 or 16, and by making electrode connections by heating the device above the melting point of the solder even in the solar cells 21 and 22. In the solar cells 23, it is possible to maintain the insulating distance between the planar electrodes 5 of the adjacent solar cells through the thickness of the solder electrode 19. Therefore, it is not necessary to remove a portion of the planar electrode 5 as in the solar cells of the first and second embodiments.
In the above-described embodiments, a rectangular solar cell is described, but the configuration of the solar cell is not restricted to a rectangular shape.
In the second and third embodiments, solar cell production methods for producing several solar cells at the same time are described but, as in the first embodiment, the solar cells may be individually produced.
As is evident from the foregoing description, according to the present invention, since the first electrode and the connection electrode are both produced on a first surface of a semiconductor substrate, the connection between the first electrode and the connection electrode of adjacent solar cells can be carried out on a single surface of each cell. As a result, a solar cell device in which serial connection of solar cells can be completed easily and precisely is easily obtained. | A solar cell includes a first conductivity type semiconductor substrate, a second conductivity type semiconductor layer disposed at a first surface of the semiconductor substrate, a first electrode disposed on the semiconductor layer, a second electrode disposed on the first semiconductor substrate opposite the layer, a connection electrode disposed on the first surface f the semiconductor substrate insulated from the semiconductor layer, and an electrically conducting layer electrically connecting the second electrode and the connection electrode extending in the direction of the thickness of the semiconductor substrate. Since the first electrode and the connection electrode of the solar cell are both disposed on the first surface of the semiconductor substrate, the interconnection of a pair of adjacent solar cells is greatly simplified. | 7 |
BACKGROUND OF THE INVENTION
This invention relates to surgical instruments and, more particularly, to a novel electro-surgical dissection and cauterization instrument for use primarily in laparoscopic/endoscopic procedures.
Many surgical procedures of today involving the removal and/or cauterization of tissue (e.g. endometriosis, lysis of adhesions, cholecystectomy, appendectomy, etc.) are performed with an electro-surgical dissection and cauterization instrument either in open surgery where the surgeon has direct view and access to the operation site, or in combination with an endoscope. Referring to the endoscopic surgery and, in particular, laparoscopic surgery which refers specifically to the abdominal area, the surgeon first makes usually several small, spaced incisions through the abdominal wall of the anesthetized patient. A source of compressed CO 2 is then delivered through one of the incisions to inflate the abdomen which effectively raises the abdominal wall above the organs and intestines of the patient. A space is thereby created therebetween which facilitates manipulation of surgical instruments which have been inserted into the abdomen through one of the incisions.
The surgeon views the internal operation site with a laparoscope which is a specialized type of scope inserted into the abdomen through an incision. The laparoscope is attached to a miniaturized, surgical camera assembly which operates by transmitting the image the camera is directed at inside the abdomen of the patient to the laparoscope eyepiece and/or a CRT screen in the operating room. A trochar is typically positioned within the incision to provide a smooth passageway for the instruments into and out of the abdomen. The electro-surgical instrument passes through the trochar to reach and perform surgery on the patient by the surgeon carefully manipulating the exposed end of the instrument.
Electro-surgical instruments are used primarily to separate and remove diseased tissue from healthy tissue such as polyps from the colon, for example. They are also used as probes to move tissue about during exploratory surgery. Supplying the instrument with controlled, electrical energy is well known in the art. With the patient properly grounded, a high frequency electric current is discharged at the distal, electrode end of the tool which augments its cutting capability while simultaneously cauterizing bleeding tissue and blood vessels. The electro-surgical instrument includes a proximal end with a plug permitting connection of the tool to an electro-surgical unit which supplies electric energy to the distal, electrode end of the tool. A rigid, linear insulating sleeve surrounds the instrument which delivers electric energy from the proximal, plug end to the distal, electrode end which itself is formed of electrically conductive material such as stainless steel.
The instrument's distal electrode may be found in a variety of configurations, each different configuration serving a different, specific function. For example, a working tip electrode in the shape of a snare or hook is used for grasping and pulling at tissue while a working tip electrode in the shape of a flattened spatula is used primarily to move tissue about and/or to cauterize bleeding tissue. Many other working tip electrode configurations appear on the market every day as the needs and likes of surgeons change.
In most, if not all, of the dissecting tools available today, the working tip electrode of the instrument just described extends directly from the distal end of the insulating sleeve. As such, there is a minimum of distance between the sleeve and the working tip electrode which, in many instances of use, obstructs or impairs the surgeon's view of the operation site as viewed in either complete open surgery or with a laparoscope during the procedure just described. The problem exists due to the small size of the working tip electrode in relation to the relatively large diameter of the sleeve from which it extends.
A second problem surgeons have reported when using present day electro-surgical instruments is that the portion of the working tip electrode directly adjacent the sleeve occasionally makes inadvertent contact with healthy tissue surrounding the surgical work site. This has resulted in unintentional cauterization of healthy tissue which poses serious consequences to both patient and surgeon alike.
It is therefore a principle object of the present invention to provide an electro-surgical instrument including a rigid arm extending between the distal, working tip electrode and the insulating sleeve. The arm includes at least a portion thereof laterally offset from the longitudinal axis of the sleeve whereby obstruction of the surgeon's view of the working tip electrode and surgical work site by the sleeve is substantially reduced.
It is a further object of the present invention to provide an electro-surgical instrument which provides an electrical insulating layer along the entire length of the tool up to the exposed working tip electrode such that inadvertent cauterization of tissue with portions of the tool other than the working tip electrode is eliminated.
It is another object of the present invention to provide a single-use, disposable, electro-surgical and cauterizing instrument for endoscopic procedures which is designed for easy handling and use by the surgeon.
Other objects will in part be obvious and in part appear hereinafter.
SUMMARY OF THE INVENTION
In accordance with the foregoing objects, the invention comprises an electro-surgical dissecting and cauterizing instrument for use primarily in standard endoscopic procedures which include the use of an endoscope to view the operation. The instrument has also proved very useful in open surgeries which do not include the use of an endoscope. An electric plug is included at the instrument's proximal end for connecting the tool to a conventional, electro-surgical unit which supplies high frequency electric energy to the working tip electrode of the tool at the control of the surgeon. The electric energy is delivered to the distal, working tip of the tool via a conductive rod surrounded by a linear, rigid sleeve formed of an insulating material, the sleeve extending from the plug end to the distal end of the tool which includes the working tip electrode.
The distal end of the tool includes an electrically conductive, rigid arm extending from the sleeve portion of the tool. Although several embodiments of the tool will be described in detail below, in each embodiment of the tool the arm extends from the sleeve and includes portions laterally offset from the longitudinal axis of the sleeve. The working tip electrode is formed at the free end of the arm and is used to make direct contact with the patient at the internal operation site. A thin jacket of insulating material is disposed upon the arm from the point where it extends from the sleeve right up to, but not including, the working tip electrode.
The working tip electrode comes in many different shapes depending on the needs of the surgeon in a particular surgical application. Electrode tips to be described in detail below include a hook and flattened spatula, for example. The fact that portions of the arm which extend between the sleeve and working tip are laterally offset from the main axis of the sleeve provides for maximum visualization of the working tip electrode and operation site by the surgeon.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side, elevational view of a first embodiment of the electro-surgical dissecting and cauterizing instrument shown operably connected to a conventional, electro-surgical unit in the intended manner;
FIG. 2 is a perspective, fragmentary view of the distal working tip end of the electro-surgical instrument seen in FIG. 1;
FIG. 3 is a side, elevational, enlarged view of the distal end of the electro-surgical instrument seen in FIG. 2;
FIG. 4 is a top view of FIG. 3;
FIG. 5 is a perspective, fragmentary view of a second embodiment of the distal end of the electro-surgical instrument;
FIG. 6 is an enlarged, side, elevational view of FIG. 5;
FIG. 7 is a bottom, fragmentary view of the working tip end of the arm as taken along the line 7--7 in FIG. 6;
FIG. 8 is a perspective, fragmentary view of the distal end of a third embodiment of the electro-surgical instrument;
FIG. 9 is an enlarged, side, elevational view of FIG. 8; and
FIG. 10 is a bottom, fragmentary view of the working tip end of the arm as seen along the line 10--10 in FIG. 9.
DETAILED DESCRIPTION
Referring now to the drawings, there is seen in FIG. 1 a first embodiment of the electro-surgical dissecting and cauterizing instrument 10 including a distal, working end 12 and a proximal end 14 which includes an electric plug such that instrument 10 may be releasably and operably connected to a conventional, electro-surgical control unit 16. Control unit 16 is supplied high frequency, electrical energy via power supply 18 and further includes a switch means 20 which is used to control the flow of electrical energy from unit 16 to instrument 10. As such, a surgeon manually grasps unit 16 to work instrument 10 as described below. Although unit 16 is shown and described herein for the purpose of illustrating a typical electrical unit with which instrument 10 would be used, it is understood that plug 14 may be easily adapted to connect to a variety of electro-surgical units available today.
Dissecting and cauterizing instrument 10 is used primarily in surgical procedures which may or may not include the use of an endoscope to view the operation site. For purposes of description, the surgical procedure using an endoscope will be discussed. Also, surgical procedures of the type discussed herein are termed laparoscopic because they target the abdominal area. The type of endoscope used in the abdomen is therefore termed a laparoscope. In particular, the surgeon inserts distal end 12 into the abdomen of the anesthetized patient through a trochar (not shown) positioned within an incision made in the abdominal wall. The operation site is viewed at the eyepiece of the laparoscope and/or on a CRT screen by passing the laparoscope (also not shown) through an adjacent incision in the abdomen which has been previously inflated with CO 2 as is customary surgical procedure in laparoscopic surgery of this type. The raising of the abdominal wall above the innards of the patient with the CO 2 creates a space therebetween which increases maneuverability of instrument 10 within the abdomen besides increasing the viewing area of the surgical site with the laparoscope. Examples of typical laparoscopic procedures in which dissecting and cauterizing instrument 10 would be used are lysis of adhesions, cholecystectomy and appendectomy.
Dissecting and cauterizing instrument 10 includes a rigid insulating sleeve 22 which surrounds conducting rod 24 extending from plug 14 to distal end 12. Distal end 12 is seen to include a rigid arm 26 extending from substantially the center of the distal end 21 of sleeve 22. A working tip 28 electrode in the shape of a hook in the embodiment of tool 10 seen in FIGS. 1-4 integrally extends from arm 26. Arm 26 and working tip electrode 28 are formed of electrically conductive material such as stainless steel and are supplied electrical energy via a conductive rod 24 extending through sleeve 22. A thin layer or jacket of insulating material 30 in the form of a TEFLON heat-shrink tubing is disposed upon arm 26 from sleeve 22 to the base of working tip electrode 28.
Prior art electro-surgical instruments of which the present inventors are aware do not include an arm such as 26 extending between the working tip electrode 28 and end of sleeve 22 but instead have their working tip electrodes extend directly from the sleeve. As such, the view of the operation site is obstructed because of the close proximity of the sleeve to the working tip electrode since the diameter of the sleeve is substantially larger than the size of the working tip electrodes. To overcome this problem, the present dissecting and cauterizing instrument 10 includes arm 26 to effectively space working tip electrode 28 from sleeve 22. Furthermore, arm 26 is seen to include portions laterally offset from the linear axis x--x extending through the center of sleeve 22 and arm 26. This feature also increases the visualization of the surgical work site by having the working tip electrode 28 extend from a portion of the arm 26 which lies along an axis y--y which is parallel to and spaced from linear axis x--x of sleeve 22.
Referring to FIG. 3, arm 26 is seen to extend linearly from sleeve 22 for a first length having a distance d 1 and bend downwardly at an approximately 150 degree angle a 1 , with respect thereto for a second length having a distance d 2 . Arm 26 then bends upwardly at an approximately 150 degree angle a 2 to extend for a third length having a distance d 3 . As such, it may be seen that the first length of arm 26 labeled d 1 extends along linear axis x--x of sleeve 22 which is spaced from and extends parallel to third length d 3 . Working tip electrode 28 is seen to integrally extend from the distal end of third length d 3 and bend toward axis x--x to form a hook which is used primarily for pulling at tissue.
The electricity which flows through arm 26 and electrode hook 28 at the control of the surgeon augments the cutting capability of hook 28 and cauterizes bleeding blood vessels. To prevent unintentional cauterization with portions of instrument 10 other than hook 28, an insulating jacket 30 is disposed upon the entire length of arm 26.
Referring to FIGS. 5 and 6, a second embodiment of instrument 10 is seen. In this second embodiment, arm 26' linearly extends from sleeve 22' for a first length having a distance D 1 as with the embodiment of FIGS. 1-4, bending downwardly and then upwardly at approximately 135 degree angles A 1 and A 2 for second and third lengths having distances of D 2 and D 3 , respectively. As such, the third length of arm 26' spanning distance D 3 lies along an axis Y--Y which is parallel to and spaced downwardly from the linear axis X--X of sleeve 22' where the first length of arm 26' spanning distance D 1 lies.
Arm 26' includes a third bend in an upwardly direction at an approximately 159 degree angle A 3 and extends linearly therefrom for a fourth length having a distance D 4 , crossing linear axis X--X such that the working tip electrode 32 lies on the side of axis X--X opposite to which axis Y--Y lies. It will be noticed in FIGS. 5-7 that working tip electrode 32 is in the shape of a flattened spatula which has a radial axis r--r which intersects linear axis Y--Y. Spatula 32 proves especially useful for cauterizing bleeding blood vessels rather than removing tissue from the patient's body. An insulating jacket 30' is disposed upon arm 26' from the distal end of sleeve 22' to the base of working tip electrode 32 to prevent any portion of arm 26' from unintentionally contacting and cauterizing healthy tissue surrounding the operation site.
Referring now to FIGS. 8, 9 and 10 which show yet a third embodiment of the invention, arm 26" is entirely linear and extends from sleeve 22" along an axis z--z which makes an approximately 6 degree acute angle A 4 with linear axis Z--Z of sleeve 22". Working tip electrode 32', which is also in the shape of a substantially circular, planar spatula, extends upwardly from arm 26" toward axis Z--Z. Working tip electrode 32' has a radial axis R--R which intersects linear axis Z--Z at an obtuse angle A 5 . An insulating jacket 30" is disposed upon arm 26" from sleeve 22" to working tip electrode 32'.
Based on the foregoing description of three embodiments of the invention, it may be realized that the length and configuration of the arms 26, 26' and 26" permit each of the respective working tip electrodes 30, 32 and 32' to be significantly spaced from and laterally offset from the longitudinal axis of the sleeve. This permits an enhanced viewing area of the surgical work site and working tip electrode for the surgeon. While the invention has been shown and described with particular reference to preferred embodiments thereof, it will be appreciated to those skilled in the art that variations in working tip electrode configuration and specific lengths and angles of the arm portion of the tool may be made to fit a particular surgical need without departing from the full scope of the invention as is set forth in the claims which follow. | An electro-surgical dissecting and cauterization tool comprises a linear, rigid insulating sleeve surrounding means providing an electric conducting path between a proximal, electric plug end and working tip electrode distal end. The plug attaches the tool to a conventional electro-surgical unit which supplies electrical energy to the working tip electrode end of the tool. A rigid arm extends between the sleeve and the working tip electrode and includes portions laterally offset from the main axis of the sleeve to increase visualization of the working tip electrode during surgery. | 0 |
FIELD OF THE INVENTION
[0001] The present invention relates to a pharmaceutical composition containing the nicotinate salt of amlodipine. The pharmaceutical composition can be used as an antihypertensive or antiischemic agent. The present invention also relates to a method of preparing the pharmaceutical composition.
BACKGROUND OF THE INVENTION
[0002] The compound amlodipine, which has the generic name of 3-ethyl 5-methyl ±2-[(2-aminoethoxy)methyl]-4-(2-chlorophenyl)-1,4-dihydro-6-methyl-3,5-pyridine dicarboxylate, was first disclosed in EP-B1-0 089 167 as a new substance and a useful anti-ischaemic and anti-hypertensive agent. Amlodipine is sold in tablet form by Pfizer Inc. under the tradename NORVASC®, and in capsule form by Novartis under the tradename LOTREL.
[0003] Amlodipine belongs to a class of dihydropyridines (DHP). This class of DHP is generally referred to as calcium channel blockers or calcium antagonists. They act to reduce the movement of calcium into the cell and are thus able to delay or prevent the cardiac contracture, which is caused by an accumulation of intracellular calcium under ischemic conditions. Excessive calcium influx during ischemia can have a number of additional adverse effects that would further compromise the ischemic myocardium. These include less efficient use of oxygen for ATP production, activation of mitochondrial fatty acid oxidation and, possibly, promotion of cell necrosis. Thus calcium antagonists are useful in the treatment or prevention of a variety of cardiac conditions, such as angina pectoris, cardiac arrythmias, heart attacks and cardiac hypertrophy. Calcium antagonists also have vasodilator activity since they can inhibit calcium influx in cells of vascular tissue and are thus also useful as antihypertensive agents and for the treatment of coronary vasospasm.
[0004] Though effective as a free base, amlodipine is best known to be administered with pharmaceutically acceptable acid addition salts. For example, U.S. Pat. No. 4,572,909 discloses the pharmaceutically acceptable acid addition salts of amlodipine as those formed from acids which form non-toxic acid addition salts containing pharmaceutically acceptable anions, such as the hydrochloride, hydrobromide, sulphate, phosphate or acid phosphate, acetate, maleate, fumarate, lactate, tartrate, citrate and gluconate salts. The maleate salt being presented as the most preferred compound.
[0005] U.S. Pat. No. 4,879,303 discloses several improved pharmaceutical salts of amlodipine, including mesylate, besylate, tosylate, succinate, and salicylate. In particular, the besylate salt of amlodipine is described as the most preferred compound which demonstrates improved solubility, stability, non-hygroscopicity and processability. Amlodipine besylate is prepared by reacting free base amlodipine with benzenesulphonic acid or ammonium benzenesulphonate in an inert solvent such as industrial methanol at the temperature of 5° C.
[0006] U.S. Pat. No. 4,806,557 discloses certain DPHs which are pro-drugs of amlodipine and intermediates useful in the preparation of these pro-drugs. The pharmaceutically acceptable salts of these pro-drugs include hydrochloride, hydrobromide, sulphate or bisulphate, phosphate or acid phosphate, acetate, citrate, fumarate, gluconate, lactate, maleate, succinate, tartrate, methanesulphonate (also known as mesylate), benzenesulphonate (also known as besylate) and p-toluenesulphonate (also known as tosylate) salts.
[0007] U.S. Pat. No. 5,438,145 discloses a process for the preparation of amlodipine besylate which is different from that described in U.S. Pat. No. 4,879,303. The process described in U.S. Pat. No. 5,438,145 includes the reaction of amlodipine and benzenesulphonic acid in methanolic or aqueous methanolic medium at a temperature from 20° C. to the reflux temperature.
[0008] U.S. Pat. No. 6,046,337 discloses yet another process of preparing amlodipine besylate which, according to the patentees, has the advantage of carrying out the process in a simple way, achieving high yields, and not having to isolate the amlodipine base.
[0009] In the invention to be presented in the following sections, a novel and improved pharmaceutically acceptable salt form of amlodipine is described. The preferred pharmaceutically acceptable salt is nicotinate. Nicotinate is the salt form of nicotinic acid, an essential water soluble vitamin which is best known for its effect on pellagra and as a component of NADP and NAD. The nicotinate salt of amlodipine demonstrates stability, non-hygroscopicity and processability similar to those of amlodipine besylate. The solubility of amlodipine nicotinate is far better than that of amlodipine besylate.
SUMMARY OF THE INVENTION
[0010] The present invention provides a pharmaceutical composition which contains a nicotinate salt of a dihyropyridine (DHP) class calcium channel blocker drug. Optionally, the pharmaceutical composition is in admixture with excipients. The preferred DHP class calcium channel blocker is amlodipine. The preferred amlodipine nicotinate contains amlodipine and nicotinate at a molar ratio of about 1:1.008. The solubility (in water at room temperature) of the nicotinate salt of amlodipine is more than 2 mg/ml, preferably at about 6 mg/ml. The pH value of the nicotinate salt of amlodipine is at about 5.0 and 6.0. The pharmaceutical composition of the present invention can be in the form of tablets, capsules, and/or sterile aqueous solutions.
[0011] The present invention also provides a method for preparing the pharmaceutical composition, which includes the steps of: (1) dissolving a free base amlodipine in a lower alkyl alcohol to form an amlodipine solution; (2) adding nicotic acid to the amlodipine solution to form the amlodipine nicotinate mixture; and (3) slowly cooling down the amlodipine nicotinate mixture to 0° C. to form the pharmaceutica composition.
[0012] The lower alkyl alcohol used for solubilizing the free base amlodipine includes, but is not limited to, methanol, ethanol, propanol, isopropanol, butanol, isobutanol, pentanol, and isopentanol. The preferred lower alkyl alcohol is ethanol. It is preferred to disslove the free base amlodipine in ethanol with heat (at 30° C.—the reflux temp of selected solvent) and stirring. After the addition of the nicotinate to the dissolved amlodipine solution, the amlodipine nicotinate mixture is gradually cooled down to 0° C. in about 1 hour.
[0013] The amlodipine nicotinate mixture is further purified by filtration using conventional method(s) and commercially available filtration device or filters. The filtered amlopidine nicotinate is further washed with ethyl acetate and dried under reduced pressure (at 25° C. and 760 mm-Hg).
[0014] The pharmaceutical composition of the present invention is suitable for use as an antihypertensive or antiischaemic agent. It can be used to treat patients with hypertension or ischaemia by orally or intraperitoneally administering an effective amount of the pharmaceutical composition to patients.
DETAILED DESCRIPTION OF THE INVENTION
[0015] There are three major classes of calcium channel blockers, which are (1) dihydropyridine (such as nifedipine), (2) phenylalkamine (such as verapamil), and (3) benzothiazapine (such as diltiazem). Amlopidine belongs to the dihydropyridine (DHP) class of calcium channel blockers. Other DHP includes nifedipine, nicardipine (Cardene®), nimodipine, nitrendipine (Nitrepin®), nisoldipine (Sula®), felodipine, isradipine (DynaCirc®), lacidipine, lercanidipine, benidipine (Coniel®), vatanidipine, and pranidipine.
[0016] The amlodipine nicotinate of the present invention has a chemical structure as shown below:
[0017] which is structurally and physically distinctive from the currently available besylate (also known as benzenesulphonate) salt of amlopidipine. See Table 1 infra.
[0018] The nicotinate salt of amlodipine of the present invention was prepared by first placing the amlodipine free base in ethanol or an aqueous ethanolic mixture. The ethanol mixture was then heated with stirring until the solid was completely dissolved. Nicotinic acid was added to the resultant solution and the mixture was slowly cooled down to 0° C. for about 1 hour. The solids formed were collected by filtration, and further washed with ethyl acetate. The final product of the present invention was obtained by drying under reduced pressure.
[0019] The following example is illustrative, but not limiting the scope of the present invention. Reasonable variations, such as those occur to reasonable artisan, can be made herein without departing from the scope of the present invention.
EXAMPLE 1
Preparation of Nicotinate Salt of Amlodipine
[0020] The pharmaceutical composition of the present invention was prepared as follows:
[0021] Amlodipine free base (4.09 g) was added to 40 mL of ethanol. The mixture was heated at reflux and stirred until the solid was completely dissolved. Nicotinic acid (1.23 g) was added to the amlodipine solution and then the mixture was slowly cooled down to 0° C. within one hour. The solids formed were isolated by filtration, washed with ethyl acetate and dried under reduced pressure to yield 4.51 g of amlodipine nicotinate.
[0022] The molar ratio of amlodipine free base to nicotinic acid added was 1:1.008.
EXAMPLE 2
Identification of Nicotinate Salt of Amlodipine
[0023] The nicotinate salt of amlodipine of present invention was identified using the proton ( 1 H) and carbon-13 ( 13 C) nuclear magnetic resonance (NMR) spectroscopy. The 1 H-NMR chemical shifts of the chemical in deuterated chloroform (CDCl 3 -d) are tabulated in Table 1:
TABLE 1 Identification of Nicotinate Salt of Amlodipine by Proton ( 1 H) and Carbon-13 ( 13 C) Nuclear Magnetic Resonance (NMR) Spectroscopy Chemical Shift (ppm) Multiplicity Functional Group 1.08 Triplet —OCH 2 CH 3 J = 7.1 2.13 Singlet —CH 3 3.14 Multiplet —OCH 2 CH 2 NH 2 3.49 Singlet —OCH 3 3.70 Multiplet —O CH 2 CH 2 NH 2 3.93 Multiplet —O CH 2 CH 3 4.61 Quartet —C—CH 2 —O J = 9.2 5.52 Singlet —C—C—H 6.62-7.24 Multiplet —Ar—H, 8H 7.78 Singlet —NH 8.14-8.50 double duplet —NH 2 J = 68 Hz, J = 36 Hz 9.10 Singlet —NH
[0024] The 13 C NMR chemical shifts of the chemical in deuterated chloroform (CDCl 3 -d) are at 14.16; 18.77; 37.27; 39.71; 50.68; 59.90; 67.98; 76.99; 102.61; 103.42; 123.30; 126.82; 127.37; 129.25; 131.14; 131.39; 132.33; 137.35; 144.34; 144.70; 145.62; 150.41; 151.11; 167.22; 167.99; and 171.10 ppm.
EXAMPLE 3
Comparison Between Amlodipine Nicotinate and Amlodipine Besylate
[0025] Amlodipine nicotinate was compare to amlodipine besylate in Table 2 as shown below:
TABLE 2 Comparative Studies Between Amlodipine Nicotinate and Amlodipine Besylate Stability Solubility in Test (% of Sample Water at Purity) Room (3-week) Temperature pH Value 45° C. 75° C. (mg/ml) Amlodipine 6.09 99.6 97.8 2.0 Besylate Amlodipine 5.34 99.7 99.2 6.0 Nicotinate
[0026] As shown in Table 2, the aqueous solution of amlodipine nicotinate had a pH value of 5.34. In comparison, the pH value of the aqueous solution of amlodipine besylate was 6.09.
[0027] Amlodipine nicotinate also showed improved water solubility over amlodipine besylate. At the ambient temperature (room temperature of about 25° C.), a saturated aqueous solution of amlodipine nicotinate contains about 6.0 mg of the chemical per mL of water. In comparison, a saturated aqueous solution of amlodipine besylate contains about 2.0 mg of the chemical per mL of water.
[0028] The stability of amlodipine nicotinate and amlodipine besylate was tested at 45° C. and 75° C. for 3 weeks. As shown in Table 2, at 45° C., the stability of amlodipine nicotinate was similar to that of amlodipine besylate, both showed about 100% unchanged rates (99.7% vs. 99.6%, respectively). However, at 75° C., amlodipine nicotinate demonstrated better stability than amlodipine besylate (99.2% vs. 97.8%, respectively).
[0029] While the invention has been described by way of examples and in terms of the preferred embodiments, it is to be understood that the invention is not limited to the disclosed embodiments. On the contrary, it is intended to cover various modifications as would be apparent to those skilled in the art. Therefore, the scope of the appended claims should be accorded the broadest interpretation so as to encompass all such modifications. | The present invention discloses a novel and improved pharmaceutical salt, nicotinate, of amlodipine having the following formula:
The present invention also discloses mehods for preparing and using the same. | 2 |
FIELD OF THE INVENTION
[0001] The invention relates generally to water-based polymer drilling fluids.
BACKGROUND OF THE INVENTION
[0002] A major problem when drilling subterranean formations containing heavy crude oil and bitumen-rich oil sands is that the bitumen or heavy oil accretes or sticks to drilling components resulting for example in tar-like materials being stuck to tubulars or solid control equipments and surface fluid handling equipments. Bitumen can also cause foaming of surfactants. This situation forces the operators to frequently stop the drilling process in order to remove the accumulated bitumen or to get the foaming under control, resulting in time waste and thus decrease in productivity.
[0003] Various solutions have been proposed in the prior art including modifications to the composition of conventional drilling fluids to prevent the accretion. Such modifications are outlined for example in published PCT applications WO 03/008758 of Mckenzie et al., WO 2004/050790 of Wu et al., and WO 2004/050791 of Ewanek et al. In particular, Ewanek et al. disclose an aqueous drilling fluid comprising a cationic polyacrylamide (CIPA) that encapsulates the bitumen or heavy oil, preventing its accretion to drilling components.
[0004] While the drilling fluids known in the art are useful, there remain ongoing problems associated with their use, in particular regarding the viscosity of the fluid. A preferred drilling fluid would have a viscosity that is suitable for limiting cationic-anionic attraction between the cationic bitumen encapsulator and the anionic fluid viscosifier, thus avoiding flocculation. Also, it has been noted that cationic bitumen encapsulators are difficult to mix with water due to the fact that their manufacturing process does not allow for a suitable additive dispersion effect on the polymer.
[0005] There is therefore still a need for more simple, efficient and cost effective solutions to this problem.
SUMMARY OF THE INVENTION
[0006] The inventors have discovered that using a water-based drilling fluid comprising a non-ionic or anionic polymer significantly reduces accretion of bitumen or heavy oil to drilling components during a drilling process. Of particular interest are non-ionic and anionic polyacrylamides. They may be used in a pH medium of between about 1 to about 13.
[0007] The invention thus provides according to an aspect for a water-based drilling fluid comprising a polymer chosen from the group comprising anionic and non-ionic polymers.
[0008] The polymer may be a non-ionic polymer or an anionic polyacrylamide. The non-ionic polyacrylamide may have the general formula:
[0000]
[0009] wherein:
[0010] R 1 , R 2 and R 3 are each independently selected from H and a C 1 to C 6 linear, branched, saturated, unsaturated or cyclic alkyl group optionally containing at least one heteroatom; and
[0011] n ranges from 10,000 to 1,000,000.
[0012] And the anionic polyacrylamide may have the general formula:
[0000]
[0013] wherein:
[0014] R 4 to R 9 are each independently selected from H and a C 1 to C 6 linear, branched, saturated, unsaturated or cyclic alkyl group optionally containing at least one heteroatom;
[0015] m1 and m2 each independently range from 10,000 to 1,000,000; and
[0016] X + is selected from the group consisting of Li + , Na + , K + and a quaternary ammonium ion.
[0017] The non-ionic polyacrylamide and the anionic polyacrylamide may respectively have formulae 2 and 4 below.
[0000]
[0018] The pH of the water-based drilling fluid may be between about 1 to about 13 or between about 1 to about 7. The anionicity of the anionic polyacrylamide may be between 0 to 100% or less than about 1%. The molecular weight of the polyacrylmide may be between about 1 to about 30 million, or between about 1 to about 15 million, or between about 8 to about 10 million. The non-ionic polyacrylamide may be NF 201™ or NE 823™ or equivalent polymers from other manufacturers; and the anionic polyacrylamide may be AF 203™, AF 204™, AF 204RD™, AF 207™, AF 207RD™, AF 247RD™, AF 250™, AF 211™, AF 215™, AF 251™, AF 308™, AF 308HH™, DF 2020-D™, NE 823™, AE 833™, AE 843™, AE 853™, AE 856™, AD 855™, AD 859™, AE 874™, AE 876™, DF 2010™, DF 2020™ or equivalent polymers from other manufacturers as outlined in Table 7.
[0019] In another aspect, the water-based drilling fluid according to the invention may be used together with an organic acid, an inorganic acid, an organic salt, and inorganic salt or a mixture of these.
[0020] In yet another aspect, water-based drilling fluid according to the invention may comprise fluid additives, viscosifiers, fluid loss additives, weighting materials, clay formation control agents, bactericides, defoamers, lost circulation materials, bridging agents or mixtures thereof.
[0021] In a further aspect, the invention provides a method of drilling subterranean formations containing heavy crude oil and bitumen-rich oil sands, the method comprising using a water-based drilling fluid comprising a polymer chosen from the group comprising anionic and non-ionic polymers.
DESCRIPTION OF THE DRAWINGS
[0022] FIGS. 1 and 2 are photographs showing shaker screens after treatment with the drilling fluid according to the invention.
DETAILED DESCRIPTION OF THE INVENTION
[0023] The invention provides according to one aspect, for a water-based drilling fluid that comprises a non-ionic or anionic polymer. The polymer may be a polyacrylamide of general formula 1 (NIPA) or 3 (AIPA), and obtained respectively according to the following chemical reactions:
[0000]
[0024] The non-ionic polyacrylamide 1 is a homopolymer of an acrylamide 5. Such polymer is termed “non-ionic” although slight hydrolysis of the amide group may yield a polymer of slight anionic nature, generally with an anionicity of less than 1%.
[0025] The anionic polyacrylamide 3 is obtained by copolymerisation of an acrylamide 5 with an acrylic acid 7 in the presence of a base. The anionicity of the anionic polyacrylamide may vary from 1 to 100% depending on the ratio of the monomers 5 and 7.
[0026] The following reaction schemes outlined the synthesis of polyacrylamide 2 and sodium acrylate polyacrylamide 4.
[0000]
[0027] Experiments were performed in order to establish the efficiency of the drilling fluid of the invention. The experiments were carried out according to the standards outlined in published PCT application WO 2004/050791 of Ewanek et al. Polymers used in the experiments are produced and sold by Hychemri™. Table 7 describes the characteristics of polymers used in the Examples or otherwise available from Hychem™. The experiments were generally conducted at a concentration of about 3 kg/m 3 and at a pH of less than about 7. Sulphamic acid was used to adjust the pH.
[0028] The drilling fluid of the invention can be used in just water in terms known in the art as “Floc Water”. It may also comprise one or more components including know drilling fluid additives, viscosifiers, fluid loss additives, weighting materials, clay formation control agents, bactericides, defoamers, lost circulation materials or bridging agents. Such components are generally known in the art.
[0029] Examples of fluid loss additives include but are not limited to modified starches, polyanionic celluloses (PACs), ignites and modified carboxymethyl cellulose. Weighting materials are generally inert, high density particulate solid materials and include but are not limited to carbonate calcium, barite, hematite, iron oxide and magnesium carbonate. Bridging agents can be used in the drilling fluid in order to seal off the pores of subterranean formation that are contacted by the fluid. Examples of bridging agents include but are not limited to calcium carbonate, polymers, fibrous material and hydrocarbon materials. Clay formation control agents include but are not limited to “ClayCenturion”. Examples of defoamers include but are not limited to silicone-based defoamers and alcohol-based defoamers such as 2-ethylhexanol. Bactericides that can be used with fluid according to the invention include but are not limited to glutaraldehyde, bleach and BNP.
Example 1
[0030] Table 1 shows the experiment conditions of a screening study conducted using some non-ionic and anionic polyacrylamides. The bar and cell used in the experiments were perfectly clean when NF 201™, a non-ionic polyacrylamide, was used at a pH of about 2.5. The results obtained for each of the samples are outlined below.
[0031] Sample 1: water brown in colour and slightly oily; bar fairly clean, however slightly not perfect.
[0032] Sample 2: water brown in colour and slightly oily; bar fairly clean, however cell is clean.
[0033] Sample 3: water clear; bar and cell clean.
[0034] Sample 4: water clear; bar sticking covered with a large amount of bitumen, however cell is clean.
[0035] Sample 5: water dirty; bar sticking covered with bitumen sticking to the cell.
Example 2
[0036] In another set of experiments, AF 204RD™ and NF 201™ were used at various concentrations and pH. AF 204RD™ is an anionic polymer, partially hydrolyzed polyacrylamide (PHPA), and NF 201™ is an anionic polyacrylamide. Table 2 shows the experiment conditions. The results obtained for each of the samples are outlined below.
[0037] Sample 1: water slight oil sheen on top, water is fairly clear (slight brown but almost clear); slight bar sticking, no cell sticking and no real sticking to the hands when solids are handled.
[0038] Sample 2: water slightly brown, oil dispersed through out the liquid; bar sticking, very slight cell sticking and sticking to the hands when solids are handled.
[0039] Sample 3: water was clear but brown probably due to disperser solids, minute sheen on top, can see through liquid; no bar sticking, no cell sticking, can touch and handle solids without sticking.
[0040] Sample 4; water was clear but brown probably due to dispersion of solids, minute sheen on top, can see through liquid; no bar sticking, no cell sticking, can touch and handle solids without sticking.
[0041] Sample 5: water was clear; no bar sticking, no cell sticking, can touch and handle solids without sticking.
Example 3
[0042] Experiments were conducted in order to show the effectiveness of NF 201™ on bitumen accretion, and also to show the benefits on viscosity of adding kelzan XCD™, a xanthan gum. Experiment conditions are shown in Table 3. The results obtained for each of the samples are outlined below.
[0043] Sample 1: water clear; no sticking bar.
[0044] Sample 2: slight bar sticking easily rinsed.
[0045] Sample 3: water was clear; no sticking anywhere.
[0046] It can be seen that NF 201™ used together with kelzan XCD™ not only provided a clean bar and cell, but also provided stable viscosity,
Example 4
[0047] Experiments were also conducted in order to determine a minimum concentration required for the non-ionic polyacrylamide when used together with kelzan XCD™. In addition, a cationic polyacrylamide, was used in order to compare the efficiencies of the two types of polymers. The experiment conditions are shown in Table 4. The results obtained for each of the samples are outlined below.
[0048] Sample 1: viscosity increased after hot rolling AHR indicating no detrimental effect to the xanthan gum from NF 201™.
[0049] Sample 2: fluid had slight sheen, fluid was brown in colour probably because bitumen solids dispersed through out the fluid due to mechanical erosion because of the prolonged roll; no bar sticking, slight cell sticking easily rinsed of, cell sticking most likely mechanical due to prolonged roll; sand is visible through out the fluid; no free solids remained dispersed through out the fluid.
[0050] Sample 3: very similar to sample 2; a little more fine sand stuck to the cell, no bitumen and easily rubbed off, a little more sticky than in sample 2.
[0051] Sample 4: water was fairly clear and brown in colour slight sheen; slight sticking to bar but easily rinsed off with water, cell was clean; solids looked non dispersed and original indicating encapsulation.
[0052] Sample 5: water was darker brown with a slight oil sheen on top, sheen was slightly less than in sample 4; no cell sticking, but bar had sticking that required significant cleaning; sand appears to be dispersed at the bottom, there was no sand/bitumen left after the roll.
[0053] It can be seen that results obtained with the non-ionic polyacrylamides were slightly better in bitumen accretion and superior in viscosity characteristics and ease of mixing, comparing to results obtained with the cationic polyacrylamide.
Example 5
[0054] Experiments were conducted using NF 201™ to assess the effect of pH on the activity of the polymer. The pH of the fluid was lowered using sulphamic acid, and increased using caustic soda. Table 5 shows the experiment conditions, The results obtained for each of the samples are outlined below.
[0055] Sample 1: sticking on bar, slight sticking to cell; fluid brown and not very clear.
[0056] Sample 2: very slight sticking to the bar, sticking is on the top of the bar (diameter), very little sticking to the ageing cell; liquid brown in colour and not as clear as in others samples.
[0057] Sample 3: liquid dark brown in colour; bar and cell have severe sticking.
[0058] Sample 4: water clear amber; bar and cell perfectly clean.
[0059] In can be seen that better results are obtained at a low pH. Also, pH may play a very important role in the anti-accretion behavior of the NF 201™.
Example 6
[0060] Experiments were carried out in order to assess whether the low pH altered the NF 201™ or altered the nature of the bitumen. In the experiment the pH was increased to a basic pH, and an inorganic mono valence cationic salt was added (one salt was mono valence anion and the other salt was di-valence anion in order to isolate results). An ammonium organic salt was also added. Table 6 shows the experiment conditions. The results obtained for each of the samples are outlined below.
[0061] Sample 1: water clear amber; bar and cell perfectly clean; bitumen appears to be perfectly encapsulated.
[0062] Sample 2: water clear amber; bar and cell perfectly clean; bitumen appears to be perfectly encapsulated.
[0063] Sample 3: water clear amber; bar and cell perfectly clean; bitumen appears to be perfectly encapsulated
[0064] The positive effect of mono valence cations as well as the organic ammonium salts can be seen. This shows that polymer alteration may not necessarily occur at low pH. The results of these experiments contribute to illustrate to the hypothesis that bitumen alteration may occur through the neutralization of the many negatively charged surfactants that are present in the bitumen by the positive charges of the cations and/or the positive charge of the organic salt. This neutralization of the negatively charged surfactants present in the bitumen favors attraction forces between the NF 201™ and the bitumen, thus allowing the encapsulation process to occur.
Example 7
[0065] A field trial in Northern Alberta, Canada on three wells in which bitumen formation was penetrated, was carried out. The three wells were penetrated and bitumen was encountered.
[0066] When a drilling fluid is used in the field, the fluid composition is constantly changing due to a large number of variables affecting the drilling fluid such as drilling operations, skill of rig personnel in carrying out additions of additives and rig equipment maintenance, formations drilled and types of solids entering the fluid, water sources, geological problems such as lost circulations and many more variables that affect the fluid. Thus the exact concentration of the fluid at all times may not be known. A series of basic field fluid tests are used to maintain the drilling fluid properties in a given range.
[0067] On this field trial the following additives were used: xanthan gum for viscosity control; sulphamic acid for pH control; modified starch, calcium carbonate and/or PAC for fluid loss control; “ClayCenturion” for clay formation control; NF 201T™ for bitumen sticking control as well as control of foaming and bitumen dispersion into the drilling fluid; bactericide (25% glutaraldehyde) for bacteria contamination control; sodium bicarbonate for cement contamination control; lost circulation material to combat lost circulation; and/or defoamer (2-ethylhexanol) to control foaming due to rig personnel mistake in mixing of the additives.
[0068] Concentrations of each of the above additives may vary widely depending on the working conditions. The approximate concentrations of these additives are as follows: xanthan gum, about 3.5-5.5 kg/m 3 ; modified starch, about 4-6 kg/m 3 ; PAC, about 0.5-1.5 kg/m 3 ; calcium carbonate, about 60-80 kg/m 3 ; pH was maintained below 7 using sulphamic acid; and drilled solids and bitumen laced solids, about 2.0-5% by volume. Other concentrations were measured directly as outlined below.
[0069] When running the system during the top hole section, the xanthan gum, PAC and modified starch were premix in water at the above concentrations prior to drilling surface shoe and recycled fluid from a previous well was utilized in order to have enough volume. Once these polymers were hydrated “ClayCenturion” level was increased to 6 l/m 3 . The surface shoe was drilled out with additions of sodium bicarbonate to treat the cement. Once through the shoe calcium carbonate was added at the above concentration. The NF 201™ was first pre-hydrated in water in a pre-mix tank at a concentration of about 12 kg/m 3 . While drilling ahead the pre-mix was added at a rate of about 12-15 l/minute to the active system until the concentration listed above was reached. The NF 201™ concentration was maintained by adding the pre-mix as determined from the field test.
[0070] Positive results were obtained drilling through the bitumen with no bitumen sticking to shaker screens as can be seen from photographs of the shaker screens (Photographs 1 and 2). The fluid also maintained the clean grey appearance instead of brown dirty oily look which is indicative of free bitumen. There was sight oil gathered on top of the tanks 1 m in radius from the agitators stems on the fluid surface this may be due to some lighter oil separating from the fluid. The overall concentration was negligible. The NF 201™ also mixed with ease in a pre-mix tank.
[0071] The main fluid properties maintained through the bitumen rich formation was as follows: NF 201™, about 1.0 to 2.2 kg/m 3 determined from field measure test; pH of about 6.2-8.0 from electronic pH meter (two decimal points); American Petroleum Institute fluid loss using PAC and modified starch, about 10.4-11.6 cc/30 minute; “ClayCenturion”, about 1.2-1.6 litres/m 3 determine from field test; yield point using xanthan gum, PAC and modified starch, about 9-14 Pa.
Example 8
[0072] A field application using NF 201™ was carried out on two wells located in Northern Alberta, Canada. A 17 meter of bitumen formation was penetrated in these wells. Formation was penetrated in one of these wells and bitumen was encountered. The fluid was run at similar concentrations with the exception only modified starch was used for fluid loss control. Similar methodology as in Example 7 was used to mix and maintain fluid properties.
[0073] On this particular drilling operation the following additives were used; Kelzari XCD™ (xanthan gum) for viscosity control; sulphamic acid for pH control; modified starch for fluid loss control; “ClayCenturion” for clay formation; NF 201™ for bitumen sticking control and control of foaming and bitumen dispersion into the drilling fluid; and bactericide for bacteria contamination control.
[0074] As in Example 7 positive results were obtained drilling through the bitumen without bitumen sticking to the tubular and shale shakers. The NF 201™ mixed well in a pre-mix tank at similar concentrations and methodology as in Example 7.
[0075] The fluid properties maintained through the bitumen rich formation was as follows: NF 201™, about 1.2 to 1.7 kg/m 3 determined from field test; pH of about 6.5-10 from electronic pH meter (two decimal points) using sulphamic acid; American Petroleum Institute fluid loss using modified starch, about 7.8-14.2 cc/30 minutes; “ClayCenturion”, about 1.2-2.6 litres/m 3 determined from field test; and yield point using xanthan gum and modified starch, about 5.5-14 Pa.
[0000]
TABLE 1
Hot rolled at 110 F. for 2 hours.
TAR-
Sample
POLYMER
WATER
SANDS
#
POLYMER
(grams)
(ml)
(15%)
pH
1
DF 2020D
3.5
350
52.5
2.5
2
AF 102
3.5
350
52.5
2.5
3
NF 201
3.5
350
52.5
2.5
4
AE 143
8
350
52.5
2.5
5
AF 250
3.5
350
52.5
3
[0000]
TABLE 2
Hot rolled at 110 F. for 1.75 hours.
TAR-
Sample
POLYMER
WATER
SANDS
#
POLYMER
(grams)
(ml)
(15%)
pH
1
AF 204RD
3.5
350
52.5
2.5
2
AF 247RD
3.5
350
52.5
2.5
3
NF 201
3.5
350
52.5
4.49
4
NF 201
3.5
350
52.5
5.51
5
NF 201
2
350
52.5
2.5
[0000]
TABLE 3
Hott rolled at 110 F. for 2 hours.
TAR-
Sample
POLYMER
WATER
SANDS
#
POLYMER
(grams)
(ml)
(15%)
pH
1
NF 201
1
350
52.5
5.5
2
NF 201
1
350
52.5
5.5
3
NF 201
1.9
350
52.5
5.5
4
NF 201
1
350
5.5
Kelzan XCD
5
SAMPLE
SAMPLE
VISCOSITY
4 BHR
4 BHR
600
38
70
300
26
54
200
20
—
100
14
—
6
3
18.5
3
2
16
10″
1.5
—
[0000]
TABLE 4
Hot rolled at 110 F. for 13 hours and 16 minutes.
TAR-
Sample
POLYMER
WATER
SANDS
#
POLYMER
(grams)
(ml)
(15%)
pH
1
NF 201
2
350
4.5
KELZAN XCD
1.8
2
NF 201
2
350
52.5
4.95
KELZAN XCD
1.8
3
NF 201
1
350
52.5
4.49
KELZAN XCD
1.75
4
NF 201
2
350
52.5
5.8
5
Cationic
2
350
52.5
6.2
Poly-
acralamide
SAM-
SAM-
SAM-
SAM-
SAM-
SAM-
PLE
PLE
PLE
PLE
PLE
PLE
VISCOSITY
1 BHR
1 AHR
2 BHR
2 AHR
3 BHR
3 AHR
600
50
86
59
59
41
50
300
35
66
42.5
49
29
44
200
26.5
55
33.5
46
23
34
100
18
46
23
36
16
15
6
3
20
4.5
15
3
14
3
2
17
3
14
2.5
14
10″
1.5
9
1.5
7
1.5
7
AHR: after hot rolling
BHR: before hot rolling
[0000]
TABLE 5
Hot rolled at 115 F. for 2 hours.
TAR-
Sample
POLYMER
WATER
SANDS
pH
#
POLYMER
(GRAMS)
(ml)
(12%)
pH
AHR
1
NF201
1.05
350
42
8
8
2
NF201
1.05
350
42
7
7
3
NF201
1.05
350
42
6
7
4
NF201
1.05
350
42
4
5.5
[0000]
TABLE 6
Hot rolled for 1.5 hours at 115 F.
TAR-
Sample
POLYMER
WATER
SANDS
pH
#
POLYMER
(grams)
(ml)
(14.8%)
pH
AHR
1
NF 201
1.05
350
52
9
10
KCl
3% (wt.)
2
NF 201
1.05
350
42
9
11
K 2 SO 4
3% (wt.)
3
NF 201
1.05
350
42
9
9
ClayCenturion
5
[0000]
TABLE 7
Competion
Competion
Competion
Competion
Hychem
Molecular Weight
Charge
Equivalent -
Equivalent -
Equivalent -
Equivalent -
Polymer
Polymer Type
(millions)
%
CIBA
Cytec
Nalco
Kelco
NF-201
Non-Ionic/Polyacrylamide
10
0
Alcomer 80
CYDRILL/CYFLOC 4500
MF 1
DF2020
Anionic/Polyacrylate
very low <200K
100
74L
Cygaurd
(~100,000)
AF102
Anionic/PHPA
8-10
5
AE143
Anionic/Polyaclamide
8
20
AF250
Anionic/Polyacrylate
0.5
70
507
Cypan
AF204RD
Anionic/PHPA
10
15
338RD
AF247RD
Anionic/PHPA
4 to 5
30
60RD
AF203
Anionic/PHPA
10
5
AF204
Anionic/PHPA
10
10
CYDRILL/CYFLOC 4010, 4020
AF207
Anionic/PHPA
10
30
110, 120
CYDRILL/CYFLOC 4000, 4001
AF207RD
Anionic/PHPA
10
30
110RD
AF211
Anionic/Polyacrylate
10
100
180
Cyex
AF215
Anionic/Polyacrylate
10
95
AF251
Anionic/Polyacrylate
0.5
100
1771
Benex
AF308
Anionic/PHPA
15
40
AF308HH
Anionic/PHPA
20
20
NE 823
Non-Ionic/Polyacrylamide
15
0
CYDRILL/CYFLOC 5500
AE 833
Anionic/PHPA
15
5
80L
ASP 715
MF 55
AE 843
Anionic/PHPA
15
10
90L
CYDRILL/CYFLOC 5200, 5310
ASP 720
AE 853
Anionic/PHPA
15
30
123L
CYDRILL/CYFLOC 5300
ASP 700
AE 856
Anionic/PHPA
10
30
CYDRILL/CYFLOC 5303
AD 855
Anionic/PHPA
15
30
120L/OS
AD 859
Anionic/PHPA
15
30
120L
AE 874
Anionic/PHPA
15
40
AE 876
Anionic/PHPA
15
50
DF 2010
Anionic/Polyacrylate
very low <200K
40
72L
Cytemp
(~100,000)
DF 2020D
Anionic/Polyacrylate
very low <200K
40
74L
(~100,000) | A water-based drilling fluid comprises a polymer which is a non-ionic polymer or an anionic polymer. The polymer can be a polyaerylamide. The fluid is used for drilling subterranean formations containing heavy crude oil and bitumen-rich oil sands, and may comprise additional fluid components. | 2 |
CROSS-REFERENCE TO RELATED APPLICATIONS
The present application is a division of application Ser. No. 11/392,507, filed on Mar. 30, 2006; which is a continuation of application Ser. No. 10/772,237, filed on Feb. 6, 2004; which is a division of Ser. No. 10/359,705, filed on Feb. 7, 2003; which is a division of Ser. No. 09/930,469, filed on Aug. 16, 2001; and which is a division of Ser. No. 09/553,064, filed on Apr. 20, 2000, which claims priority to French Application No. 99 05047, filed on Apr. 21, 1999 and French Application No. 99 08041, filed on Jun. 23, 1999, the entire contents of each of which is incorporated herein by reference.
The present invention relates to a method for a Code Division Multiple Access telecommunication system.
1. Discussion of the Background
The 3GPP (3 rd Generation Partnership Project) group is an association whose members originate from several regional standardization bodies including in particular the ETSI (European Telecommunication Standardization Institute) and the ARIB (Association of Radio Industries and Businesses). Its object is the standardization of a third-generation telecommunication system for mobiles. One of the fundamental aspects distinguishing third-generation from second-generation systems is that, apart from the fact that they will use the radio spectrum more efficiently, they will allow very great flexibility of service. Second-generation systems offer an optimized radio interface for certain services. For example GSM (Global System for Mobiles) is optimized for the transmission of speech (telephony). Third-generation systems will offer a radio interface adapted for all kinds of services and combinations of services.
One of the issues at stake with third-generation mobile radio systems is that of efficiently multiplexing, on the radio interface, services which do not have the same demands in teams of quality of service (QoS). Quality of service is defined, conventionally, according to at least one criterion comprising in particular a processing delay, a bit error rate and/or an error rate per transported block. These different qualities of service require corresponding transport channels having different channel codings and channel interleavings. Moreover, they demand different maximum bit error rates (BER). For a given channel coding, the demand with regard to the BER is satisfied when the coded bits have at least a certain coding-dependent ratio Eb/I. The ratio Eb/I expresses the ratio of the average energy of each coded bit to the average energy of the interference.
It follows that the different qualities of service do not have the same demand in terns of the ratio Eb/I. Now, in a system of the CDMA (Code Division Multiple Access) type, the capacity of the system is limited by the level of interference. It is therefore necessary to fix the ratio Eb/I as correctly as possible for each service. Therefore, a rate matching operation, for balancing the ratio Eb/I is necessary between the various services. Without this operation the ratio Eb/I would be fixed by the service having the greatest demand, and as a result the other services would have “too good” a quality, thereby impacting directly on the capacity of the system.
This raises a problem since it is necessary in some manner that the rate matching ratios be defined identically at the two ends of the radio link.
The present invention relates to a configuring method for defining rate matching ratios identically at the two ends of a CDMA radio link.
In the OSI model (Open System Interconnection) from the ISO (International Standardization Organization), a telecommunication equipment is modelled by a layered model constituting a stack of protocols where each level is a protocol supplying a service to the level above. Level 1 is in particular responsible for implementing channel coding and channel interleaving. The service supplied by level 1 is referred to as “transport channels”. A transport channel allows the higher level to transmit data with a certain quality of service. The quality of service is in particular characterized by the delay and the BER.
In order to satisfy the quality of service demand, level 1 uses a certain encoding and a suitable channel interleaving.
The known solutions, and in particular those proposed in the 3GPP project, will be described with regard to FIGS. 1 and 2 .
FIG. 1 is a diagrammatic view illustrating the multiplexing of the transport channels on the uplink in the current 3GPP proposal;
FIG. 2 is a diagrammatic view illustrating the multiplexing of the transport channels on the downlink in the current 3GPP proposal.
Represented in FIGS. 1 and 2 are the block diagrams for interleaving and multiplexing as defined by the current proposal by the 3GPP group, although this proposal has not yet been finalized.
In these figures, similar blocks bear the same numbers. In both cases the uplink (from the mobile station to the network) may be distinguished from the downlink (from the network to the mobile station), and only the transmission part is represented.
Each transport channel, labelled 100 , periodically receives a transport blocks set from an higher level, labelled 102 . The number of transport blocks 100 in this set, as well as their sizes, depend on the transport channel. The minimum period at which the transport blocks set is supplied corresponds to the time span of the interleaving of the transport channel. The transport channels with one and the same quality of service (QoS) are processed by one and the same processing chain 103 A, 103 B.
In each of the processing chains 103 A, 103 B, the transport channels, in particular after channel encoding and channel interleaving, are multiplexed together by concatenation in step 104 . This multiplexing is carried out per multiplexing frame. A multiplexing frame is the smallest unit of data for which demultiplexing may be carried out at least partially. A multiplexing frame typically corresponds to a radio frame. The radio frames form consecutive time intervals synchronized with the network, and numbered by the network. In the proposal by the 3GPP group, a radio frame corresponds to a duration of 10 ms.
The 3GPP proposal comprises the service-specific coding and interleaving option represented diagrammatically at 103 C. The possibility of such an option is being considered at present since its indispensability or otherwise has not yet been determined.
In the general case, a processing chain 100 A firstly comprises a step 106 during which a bit word termed the FCS (Frame Check Sequence) is attached to each transport block. The bit word FCS is typically calculated by the so-called CRC technique (Cyclic Redundancy Check) which consists in considering the bits of the transport block to be the coefficients of a polynomial P and in calculating the CRC from the remainder of the polynomial (P+P0) after dividing by a so-called generating polynomial G, where P0 is a predefined polynomial for a given degree of P. The attachment of the bit word FCS is optional, and certain transport channels do not include this step. The exact technique for calculating the bit word FCS also depends on the transport channel, and especially on the maximum size of the transport blocks. The usefulness of the bit word FCS is in detecting whether the transport block received is valid or corrupted.
The next step 108 consists in multiplexing together the transport channels (TrCH) of like quality of service (QoS). This is because those transport channels which have the same quality of service may use the same channel coding. Typically, the multiplexing at 108 is carried out by concatenating the transport blocks sets with their FCS for each transport channel.
The next step, labelled 110 , consists in performing the channel encoding. On exit from the channel encoder 110 there is a set of coded blocks. Typically, in the case of a convolutional code, we have either zero or a single coded block of variable length. The length is given by the formula:
N output =N input /(coding rate)+ N tail (length of the coded block).
with:
N output =number of bits at output (length of the coded block); N input =number of bits at input; coding rate=constant ratio; and N tail =fixed quantity of information, independent of N input , serving to empty the channel decoder cleanly at the time the coded block is received.
It is onwards of this step 110 that the uplink differs from the downlink.
In each transport channel, whether the uplink ( FIG. 1 ) or the downlink ( FIG. 2 ), a rate matching step is implemented after the channel encoding step 110 . This step is labelled 112 for the uplink and 114 for the downlink. Rate matching is not necessarily performed immediately after channel encoding 110 .
The objective of the rate matching step 112 or 114 is to balance the ratio Eb/I between the transport channels with different qualities of service. The ratio Eb/I gives the average energy of a bit with respect to the average energy of the interference. In a system using multiple access CDMA technology, the greater this ratio the greater is the quality which may be obtained. It will be understood therefore that transport channels having different qualities of service do not have the same need in terms of Eb/I, and that in the absence of rate matching, certain transport channels would have “too” good a quality of service relative to their respective needs, fixed as it is by the most demanding channel in terms of quality of service. Such transport channels would then needlessly cause interference. Rate matching therefore has a role of matching the Eb/I ratio. Rate matching is such that X bits at input give Y bits at output, thus multiplying Eb/I by the ratio Y/X, hence the matching capability. In what follows, the ratio Y/X is referred to as the rate matching ratio, also known as the rate matching ratio.
Rate matching is not done in the same way in the uplink and in the downlink.
This is because, in the uplink, it has been decided to transmit continuously, since discontinuous transmission worsens the peak/average ratio of the radio-frequency power at the output of the mobile station. The closer this ratio is to I the better. This is because, if this ratio is worsened (that is to say increased), this signifies that the power amplifier requires a greater margin (backoff) of linearity with respect to the mean operating point. On account of such a margin, the power amplifier would be less efficient and would therefore consume more for the same average power emitted, and this would in particular unacceptably reduce the mobile station's battery-powered endurance. Because it is necessary to transmit continuously on the uplink, the rate matching ratio Y/X cannot be constant. This is because the sum Y 1 +Y 2 + . . . Y k of the numbers of bits after matching must be equal to the total number of bits in the radio frame for the data. This number may take only certain predefined values N 1 , N 2 , . . . , N p . It is therefore appropriate to solve the following system in k unknowns Y 1 , . . . , Y k :
Input data: X i number of bits at input Y i number of bits at output N pr = |Y i − X i | number of bits to be repeated or to be punctured (if Y i > X i we repeat, otherwise we puncture) The puncturing/repetition rule is as follows: e = 2*N p/r − X i initial error between the current and desired puncture/repetition ratios x = 0 index of the current bit while x < X i do else e = e + 2*N p/r update the error end_if x = x + 1 next bit end_do
where X i and Eb i /I and P i are characteristic constants of each transport channel, and where it is sought to minimize N j from among the p possible values N 1 , N 2 , . . . , N p (note: P i is the maximum allowable puncture rate for a coded transport channel).
Thus, in the uplink, the rate matching ratios Y/X for each transport channel are not constant from one multiplexing frame to the next, but are defined to within a multiplicative constant: the pairwise ratios between these ratios therefore remain constant.
In the downlink, the peak/average ratio of the radio-frequency power is in any case very poor since the network transmits to several users simultaneously. The signals destined for these users combine constructively or destructively, thereby inducing wide variations in radio-frequency power emitted by the network, and hence a poor peak/average ratio. It was therefore decided that for the downlink the balancing of Eb/I between the various transport channels would be done with a rate matching having a constant rate matching ratio Y/X, and that the multiplexing frames would be supplemented with dummy bits, that is to say bits which are not transmitted, that is to say discontinuous transmission.
Thus, the difference between the uplink and the downlink lies in the fact that in the uplink the rate matching 112 is dynamic so as to supplement the multiplexing frames, whereas in the downlink the rate matching 114 is static and the multiplexing frames are supplemented through the insertion of dummy bits in the immediately following step 124 .
The rate matching, whether dynamic or static, is done either by repetition or by puncturing, according to an algorithm which was proposed to the ETSI by the Siemens Company (registered trade mark) in the technical document referenced SMG2/UMTS-L1/Tdoc428/98. This algorithm makes it possible to obtain non-integer puncture/repetition ratios, and it is given in Table 1 for information.
TABLE 1
Repetition or puncturing algorithm
Input data:
X i
-
number of bits at input
Y i
-
number of bits at output
N pr= |Y i −X i |
-
number of bits to be repeated or to be punctured
(ifY i >X i we repeat, otherwise we puncture)
The puncturing/repetition rule is as follows:
e=2*N p/r −X i
--
initial error between the current and
desired puncture/repetition ratios
x = 0
--
index of the current bit
while x<X i do
if e > 0 then --test whether bit number x
should be repeated/punctured
{open oversize bracket}
puncture or repeat bit number x
e = e + (2*Npir− 2* X;)
--update the error
else
e = e + 2*Np/r
-- update the error
end_if
x = x + 1
--next bit
- end_do
The particular feature of this algorithm is that, when it operates in puncture mode, it avoids the puncturing of consecutive bits, but on the contrary tends to maximize the spacing between two punctured bits. As far as repetition is concerned, the repetition bits follow the bits which they repeat. Under these conditions, it will be understood that it is beneficial for the rate matching to be done before interleaving. This is because, for repetition, the fact that an interleaving follows the rate matching makes it possible to space the repeated bits apart. For puncturing, the fact that an interleaver precedes the rate matching gives rise to the risk that the rate matching might puncture consecutive bits on exit from the channel encoder.
It is therefore advantageous for the rate matching to be done as high up as possible, that is to say as close as possible to the channel encoder.
Moreover, each processing chain 103 A, 103 B also comprises, after the channel encoding step 110 , a first interleaver labelled 116 for the uplink and 118 for the downlink, followed by a step of segmentation per multiplexing frame labelled 120 for the uplink and 122 for the downlink. The first interleaver 118 is not necessarily located immediately after the channel encoding 110 .
For the downlink, it is possible to place the rate matching 114 right at the output of the channel encoding 110 , since the rate matching ratio is constant. Hence, a priori only a single interleaver 118 is needed.
However, a second interleaver 136 is necessary, since the multiplexing of the transport channels of different qualities of service QoS is done by straight-forward concatenation, and since such a method would in fact limit the time span of each multiplexed block.
For the uplink the rate matching ratio may vary with each multiplexing frame. This explains the need for at least the first interleaver 116 before the rate matching 112 so as to distribute the bits of the coded block over several multiplexing frames, and for a second interleaver 128 placed after the rate matching so as to space apart the bits repeated by the rate matching 112 .
Thus in the block diagrams of FIGS. 1 and 2 may be seen two interleavers referred to in the block diagrams as the first and second interleavers. The first interleaver 116 , 118 is an interleaver whose time span is equal to the interleaving time span for the corresponding transport channel. This span may be longer than the duration of a multiplexing frame and is typically a multiple thereof in a constant ratio. This is why this first interleaver 116 , 118 is also sometimes referred to as an inter-frame interleaver.
The second interleaver 126 , 128 is also referred to as an inter-frame interleaver since its time span is that of a multiplexing frame.
Consequently the step of segmentation per multiplexing frame labelled 120 , 122 is situated between the first 116 , 118 and the second 128 , 126 interleavers (when there is a second interleaver). This step consists in segmenting the blocks which are coded and are interleaved by the first interleaver into as many segments as is equal to the ratio of the time span of the first interleaver to the duration of a multiplexing frame. This segmentation is typically done in such a way that the concatenation of the segments once again yields the interleaved coded block.
It will be noted that, in the uplink, this segmentation step 120 is necessarily located before the rate matching 112 . This is because the rate matching 112 is done according to a ratio established dynamically multiplexing frame by multiplexing frame, and it is not therefore possible to do it on a unit of data which may extend over several multiplexing frames.
In the uplink and the downlink, a step 130 of segmentation into physical channels is implemented before each second interleaver 126 , 128 . Likewise, the second interleavers 126 , 128 are followed by a step 132 of physical channel mapping for transmission proper.
At present, only the multiplexing, channel encoding, interleaving and rate matching algorithms are defined and discussed. There is no rule making it possible to fix the way in which with a size X of a block input into the bit rate matcher there is associated a size Y of the block obtained on output. We are reduced to assuming that all the combinations of the pairs (X, Y) are predefined and saved in memory in a frozen manner. Only one of the following two things is possible:
either the set of pairs (X, Y) remains frozen and no flexibility of definition of this set of pairs (X, Y) for the service concerned is obtained, which is contrary to the sought-after effect; or the set of pairs (X, Y) is negotiated between the mobile stations and the telecommunication network involved and a high number of signalling bits and hence additional immobilization of resources has to be envisaged.
A rule for determining the size Y of a rate matched block which is rate matched with the other blocks, on the basis of the size X of this block before rate matching is necessary at least in the uplink. This is because, since the services have variable bit rates, the number of transport blocks provided for each transport channel is variable. The list (X 1 , X 2 , . . . , X k ) of the sizes of blocks to be rate matched may consequently vary from multiplexing frame to multiplexing frame. Neither is the number k of elements in this list necessarily constant.
As the size Y i associated with the size X i does not depend only on X i but on the entire list (X 1 , X 2 , . . . , X k ) owing to the dynamic matching, it follows that there exists a list (Y 1 , Y 2 , . . . , Y k ) for each list (X 1 , X 2 , . . . , X k ). The number of lists may therefore be very large, at least as large as the number of combinations of transport formats. A transport format combination is a quantity defining how to demultiplex the multiplexing frame.
Thus, the sending and receiving entities should employ the same association list (X 1 , X 2 , . . . , X k )→(Y 1 , Y 2 , . . . , Y k ). The signalling of this list of association between these two entities at the time of connection of the composite of coded transport channels represents a non-negligible cost in terms of signalling bits. A composite of coded transport channels includes at least two groups of coded transport channels. Moreover, it would then be necessary to provide for the exchange of a new list of associations (X 1 , X 2 , . . . , X k )→(Y 1 , Y 2 , . . . , Y k ) with each addition or removal included within the composite of coded transport channels.
Moreover, the exact matching of the ratio Eb/I depends on the technology of the channel decoder for each quality of service QoS. The performance of such a device can vary from one manufacturer to another depending on their respective know-how. In fact, this rate matching does not depend on the absolute performance of each decoder, but on their performance relative to one another, which may therefore vary from one manufacturer to another, if the performance of one of them varies.
It is not therefore possible for the sending and receiving entities employed to be able to “negotiate” the matching of the ratios (Eb/I) through an appropriate exchange of signalling messages.
To explain this, let us imagine two qualities of service A and B, and two manufacturers M and N, M and N have the same channel decoder for A, but M has a far more efficient decoder than that of N for B. It is then clear that manufacturer M could benefit from a smaller ratio Eb/I for B as this would decrease the total power required and would therefore produce a gain in capacity which would enable M to sell more mobile telecommunication equipments to network operators by arguing thus.
It would therefore be very useful to be able to signal parameters making it possible to define the rule X→Y for determining the size Y of a block after rate matching from the size X of the block before matching. This would make it possible to negotiate or to re-negotiate the proportions of the ratios Eb/I. This signalling must be as inexpensive as possible.
This adjustment during connection of the ratios Eb/I performed by the higher levels therefore signifies that if two telecommunication stations A and B wish to establish or modify a connection over which there is a service multiplexing, then they follow the following steps:
1. B signals to A what is the maximum load N of a multiplexing frame B can send.
2. A determines the ideal proportion for A of the ratios Eb/I from:
the value of N received from B the maximum puncture rate allowed by A for each quality of service QoS, the relative demands for each quality of service QoS in terms of Eb/I the minimum performance demand specified for A.
3. A signals to B what proportion of the ratios Eb/I A expects.
Step 1 is not necessarily present. Systems may be imagined in which the maximum load is known in advance and forms part of the characteristics of the system. That said, such a system would be highly improbable in view of its lack of flexibility.
It may happen that the proportion of the ratios Eb/I which is determined by A is sub-optimal in relation to the sought-after aim which is that no transport channel should have more than it deserves. This is a compromise situation in which it is preferred to reduce the capacity of the network provided that the connection of the combination of services can be established.
Such a compromise is acceptable insofar as the degradation is within the limits fixed by the minimum performance demand defined in the system specification.
It may also happen that the actual tolerance limit is partly at the discretion of the network. This would make it possible to define non-guaranteed levels of service, in which the service is provided when the traffic conditions so permit, and otherwise it is re-negotiated downwards.
There will certainly be a specification of possible combinations of services. In this specification, for each combination of services, there will be associated a set of combinations of transport formats. This will definitely be the case for the basic services such as the conventional telephony service, and all the associated services such as call signalling, standby, etc.
However, the number of potential combinations may well increase in the future, and clear rules will then be needed in order for the higher levels to determine what combinations are possible, how to negotiate them, and/or to re negotiate them, and also in order for them to determine the set of transport format combinations for a given combination.
The higher levels ought therefore to be able with the aid of simple arithmetic algorithms to determine which combinations of transport formats are possible. To do this, there are at least three arithmetic rules which the higher levels should apply:
The first rule, concerning channel encoding, makes it possible to convert the number of elements of the transport blocks sets and their respective sizes into the number of elements of the sets of coded blocks and their respective sizes. For example, this rule may be of the type:
Y=X /(coding rate)+ N tail , where “coding rate” and “N tail ” are characteristic constants of the code.
The second rule concerning segmentation converts the size of a coded block into the size of a segment produced by the segmentation per multiplexing frame. In general this rule is a simple division by F when the transmission interval of the associated transport channel corresponds to F multiplexing frames. However, it is not yet clear whether the segmentation is equal or unequal. In the case of equal segmentation, the coded blocks have a size which is a multiple of F. In this case, all the segments are of the same size since there is no rounding error when dividing by F. In the case of unequal segmentation, the size of the segment is defined to within 1 bit, on account of the rounding-up or rounding-down error, and the serial number of the segment must be known in order to reduce the ambiguity. For example, if 80 bits are to be segmented into F equal to 8 frames, then all the segments will contain 10 bits and there is no need to know the serial number of the segment (or position of the segment) concerned in order to ascertain its size. On the other hand, if 78 bits are to be segmented into F equal to 8 frames, then 6 segments will contain 8 bits and two other segments will contain 9 bits and it is necessary to know the serial number of the segment in order to ascertain its size. The third rule is that which makes it possible to deduce, from the size X of a block to be rate matched, the size Y of the rate matched block.
This third rule is not specified and the invention solves this problem of deducing the corresponding sizes for the blocks to be matched.
SUMMARY OF THE INVENTION
The aim of the invention is to ensure that each of the sending and receiving entities of a mobile telecommunication network can be aware, in a simple manner, for each transport channel associated with one and the same quality of service, of the size Y of a block obtained at the output of the rate matching means and associated with each quality of service, as a function of the size X of the block input to the matching means.
The aim of the invention is also to minimize the number of signalling bits making it possible to define, in a manner which is common to the sending and receiving entity or entities, the size Y of a block obtained at the output of the rate matching means and associated with the size X of a block input to these rate matching means.
A further aim of the invention is to preserve the flexibility of definition of the association of the sizes Y of blocks output by the rate matching means with the sizes X of blocks input to the rate matching means.
To this end, the subject of the invention is a method for a Code Division Multiple Access telecommunication system implemented by a mobile station, said Code Division Multiple Access telecommunication system implementing a phase of communicating data conveyed by a plurality of transport channels, said Code Division Multiple Access telecommunication system comprising at least one base station and at least said mobile station, said mobile station performing a plurality of rate matching steps, each of said rate matching steps executing a transformation of an input block of an initial size into an output block of a final size by puncturing or repeating at least one bit of said input block, said method comprising:
receiving a plurality of rate matching parameters from said base station, each of said plurality of rate matching parameters being relative to a rate matching ratio for one of said plurality of transport channels;
calculating an intermediate size of said output block, for each of said plurality of transport channels, by multiplying said initial size of said input block by a corresponding rate matching parameter received from said base station; and
determining, with said mobile station, an available maximum payload for a communication in the Code Division Multiple Access telecommunication system, for at least one radio frame, from among a plurality of possible maximum payloads on a basis of a size of a possible maximum payload and a total sum of said intermediate sizes of said output blocks, each of said plurality of possible maximum payloads being relative to at least one radio frame.
LIST OF FIGURES
The invention will be better understood on reading the description which follows, given merely by way of example and with reference to the following drawings in which:
FIG. 1 is a diagrammatic view illustrating the multiplexing of the transport channels on the uplink in the current 3GPP proposal;
FIG. 2 is a diagrammatic view illustrating the multiplexing of the transport channels on the downlink in the current 3GPP proposal;
FIG. 3 is a flowchart explaining the implementation of the algorithm according to the invention for the downlink; and
FIG. 4 is a flowchart explaining the implementation of the algorithm according to the invention for the uplink.
DETAILED DESCRIPTION OF THE INVENTION
Generally, in the invention each quality of service is characterized by two integer numbers E and P. E corresponds to the ratio Eb/I, that is to say if there are several qualities of service labelled 1, 2, . . . , p, whose respective coefficients E are labelled E 1 , E 2 , . . . , E p , then the ratios Eb/I of each quality of service will be in the same proportions as the coefficients E i .
The coefficient P corresponds to the maximum puncture rate which is admissible for a given quality of service. Thus, for each quality of service 1, 2, . . . , p, there is associated a maximum puncture rate labelled P 1 , P 2 , . . . , P p . The maximum puncture rate is imposed by the channel coding implemented within the processing chain specific to the relevant quality of service. Puncturing consists in deleting coded bits. This deletion is tolerable insofar as the channel coding introduces a redundancy. However, the number of punctured bits must not be too large relative to the total number of bits coded, there is therefore a maximum puncture rate which depends on the channel coding as well as on the decoder used.
In a telecommunication system, a physical channel dedicated specifically to the transmission of control data is provided between the various sending and/or receiving entities of the system. In particular, such a channel exists between the fixed network and the mobile stations of a mobile radio communication system. The latter is commonly designated by DPCCH in the 3GPP standard (or Dedicated Physical Control Channel). It coexists alongside the physical data transmission channels designated DPDCH (or Dedicated Physical Data Channel) in this same standard.
According to the invention, to enable each entity of the telecommunication system to ascertain the set of correspondences between the sizes Y i of the rate matched blocks and the sizes X i of the blocks to be matched and to do so for each quality of service, only the pairs (E i , P) with i∈[1,p] are transmitted over the logical control data transmission channel to all the entities of the system having to communicate with one another. These pairs may be established by one of the entities or “negotiated” between several entities in a first embodiment. In a second embodiment, only the parameters (E i ) are negotiated and the parameters (P i ) are predefined for a given channel encoding. In a third embodiment, only the parameters (P i ) are negotiated and the set of parameters (E i ) is predefined for a given group of transport channels. The method for determining the correspondences between the sizes of blocks X i , Y i from the above-defined pairs (E i , P i ) will be described subsequently in the description.
Integer numbers are used for E and P since:
Calculations on integer numbers, or fixed-point calculations, are simpler to implement, stated otherwise they may be done faster or with fewer resources; The accuracy of calculations on integer numbers can be very easily quantified through the number of bits of the registers in which these integers are stored. Thus, one may easily be assured that the same rounding errors are produced in the network and in the mobile station, and hence that the result of the calculations is exactly the same on either side of the radio interface.
More precisely, the dynamics are defined as follows:
E is an integer from 1 to EMAX, P is an integer from 0 to PMAX.
Furthermore, we define the constant PBASE so that PMAX<PBASE, and so that
P PBASE
is the maximum admissible puncture rate for a given quality of PBASE service.
1 PBASE
corresponds to the granularity. PBASE is of the order of 10 4 .
The maximum admissible puncture rate
P PBASE
for the rate matching step carried out for a given quality of service is typically between 0 and 20%.
Thus, the algorithm of the invention is characterized by 3 integer constants EMAX, PMAX and PBASE.
In what follows, a fourth integer constant LBASE, concerned with the accuracy of the calculations, is used.
Let us note that although the same notation EMAX, PMAX, PBASE and LBASE is used for the uplink, that is to say from the mobile station to the network and for the downlink, that is to say from the network to the mobile station, the corresponding constants do not necessarily have the same value in both cases.
Also in what follows, the same notation X and Y is used for the uplink and for the downlink with different meanings.
Moreover, for each link we shall define a mapping denoted Q in both cases giving the value of the quality of service QoS for a given index of a block.
In the downlink, X 1 , X 2 , . . . , X k denotes the list of possible sizes before rate matching for the blocks of a given quality of service (QoS), this being for all the possible values of quality of service (QoS).
To be more precise, if the quality of service QoS takes values from 1 to p, then:
X k 0 +1 , . . . , X k 1 are all the possible block sizes for QoS 1
X k l +1 , . . . , X k 2 are all the possible block sizes for QoS 2
. . .
X k p−1 +1 , . . . , X k p are all the possible block sizes for QoS p with the convention that k 0 =0 and k p =k and k 0 <k 1 < . . . <k p .
Moreover, we consider a mapping Q from the set {1, . . . , k} of indices of block sizes for every quality of service QoS to the set of indices {1, . . . , p} of quality of services. We therefore have:
Q: {1, . . . , k}→{1, . . . , p}
i→Q(i)=j for k j−1 <i≦k j
Note that in view of the above definitions, it is possible to have the same block size twice (X i =X j with i≠j) provided that the quality of service is not the same (Q(i)≠Q(j)).
For the uplink, the blocks which are to be rate matched for a given multiplexing frame are numbered 1, 2, . . . , k and X 1 , X 2 , . . . , X k are their respective sizes.
Thus the list (X 1 , X 2 , . . . , X k ) varies from multiplexing frame to multiplexing frame. Its number k of elements is in particular not necessarily constant.
Q is a mapping from {1, . . . , k} to {1, . . . , p}, which for the relevant Multiplexing frame, associates with the index i of a block, its quality of service Q(i).
With this convention, it is possible to have the same block size twice (X i =X j with i≠j) whether or not they have the same quality of service (Q(i)=Q(j) or Q(i)≠Q(j)).
Indeed, for two blocks of like quality of service to have the same size, it is sufficient for the channel encoder to output a set of coded blocks having at least two elements of like size.
To summarize, for the downlink, 1, 2, . . . , k are indices for all the possible sizes of blocks to be rate matched, given that the block sizes corresponding to different qualities of service are counted separately. For the uplink, 1, 2, . . . , k are the indices of the list of blocks to be rate matched for a given multiplexing frame.
Y 1 , . . . , Y k are the sizes of blocks which correspond respectively to X 1 , . . . , X k after rate matching.
For the downlink, the algorithm for determining the sets of pairs (X i , Y i ) from the values E q and P q associated with the quality of service q is illustrated for one and the same processing chain (Q d(i) ) in FIG. 3 for example for an entity which receives the set of pairs of parameters (E q , P q ) while negotiating the matching of the ratios of the average energy of a bit to the average energy of the interference (Eb/I). This entity may either be the sending entity (consisting of at least one base station) for the composite of transport channels, or the receiving entity (consisting of at least one mobile station) for this composite of transport channels, depending on the entity which decides the result of the current negotiation. In most cases, it is the receiving entity for the group of transport channels which decides and it is the sending entity which implements the configuring method of the invention.
Let us assume that for every quality of service q in {1, . . . , p}, that is to say for each processing chain, we have the two characteristic integers E q and P q defined above. These are received in steps 300 A and 300 B borne by an already established transport channel. Additionally, the values X i are available, in step 300 C, whether they are predefined for quality of service q, or whether they have been negotiated.
The first step 302 of the algorithm is to calculate for every q from 1 to p an integer parameter L q defined by:
L
q
=
⌊
(
PBASE
-
P
p
)
·
LBASE
E
q
⌋
where └x┘ represents the largest integer less than or equal to x. It is clear that, according to a variant embodiment, the smallest integer greater than or equal to x is selected.
In general, any other rounding function may be suitable for any step for determining a parameter where a rounding function is to be carried out. Furthermore, two steps for determining parameters may use two different and mutually independent rounding functions.
The next step labelled 304 consists in defining the parameter LMAX by:
LMAX
=
max
q
{
L
q
}
Next, an integer S q is defined in step 306 for every quality of service q by:
S q =L MAX· E q
S q is such that the rational number
Sq PBASE · LBASE
is the minimum rate matching ratio, given the maximum puncture rate
P q PBASE
for each quality of service q.
Stated otherwise, S q must comply with the following relation:
S
q
PBASE
·
LBASE
≥
1
-
P
q
PBASE
The configuring method of the invention has the advantage according to which there is no need in particular within the context of an addition and/or a removal within the current composite of transport channels of at least one group of transport channels exhibiting the same quality of service or within the context of a modification of the ratio of the average energy of a bit to the average energy of the interference (Eb/I) which is sought for a given quality of service, to retransmit not the set of pairs of parameters {E q , P q }for all the qualities of service used, but only the pair(s) of parameters {E q , P q }associated with the group(s) of transport channels impacted by the addition and/or the modification of the ratio (Eb/I) sought.
The preceding part of the algorithm also applies in respect of the uplink. However, the end of the algorithm is specific to the downlink.
On completing step 306 , the relation X i →Y i is defined in, step 308 by:
Y
i
=
⌈
S
Q
(
i
)
·
X
i
PBASE
·
LBASE
⌉
where ┌x┐ is the smallest integer greater than or equal to x.
Knowing each value of X i and of Y i which correspond, the set of pairs of sizes (X i , Y i ) are established in step 310 .
To summarize, in the downlink, the algorithm essentially comprises the following four steps.
for
all
the
QoS
q
do
L
q
=
⌊
(
PBASE
-
P
p
)
·
LBASE
E
q
⌋
(
step
302
)
2.
L
MAX
:=
max
q
{
L
q
}
(
step
304
)
3. for all the QoS q do Sq:=LMAX·E q (step 306 )
4.
for
i
:=
1
to
k
do
Y
i
=
⌈
S
Q
(
i
)
·
X
i
PBASE
·
LBASE
⌉
(
steps
308
-
310
)
For the uplink, the algorithm for determining the sets of pairs (X i , Y j ) from the values E q and P q associated with the quality of service q is illustrated for one and the same processing chain (Q m(i) ) in FIG. 4 for example for an entity which receives the set of pairs of parameters {E q , P q } while negotiating the balancing of the ratio of the average energy of a bit to the average energy of the interference (Eb/I). This entity may either be the sending entity (consisting of at least one base station) for the composite of transport channels, or the receiving entity (consisting of at least one mobile station) for this composite of transport channels, depending on the entity which decides the result of the current negotiation. In most cases, it is the receiving entity for the composite of transport channels which decides and it is the sending entity which implements the configuring method of the invention.
For the uplink, the rate matching ratios are calculated for each multiplexing frame. Thus, it is not a question of determining a mapping X i →Y i , but rather a mapping (X 1 , X 2 , . . . , X k ) (Y 1 , Y 2 , . . . , Y k ); indeed, the sum of the Y i to Y k must be equal to the maximum payload of a multiplexing frame.
Moreover, the (potential) maximum payload of a multiplexing frame may vary from frame to frame depending on the physical resources to be used as a function of the amount of data to be transmitted (corresponding to the amount of input data for all the sizes X i to X k of the blocks transported). Hence, we can thus define a set {N 1 , . . . , N r }with, for example, N 1 ≦ . . . ≦N r of the possible maximum payloads for the multiplexing frames. More generally, the order 1, 2, . . . r of the indices of N 1 , N 2 to N r corresponds to the order of preference of the physical resources allowing transmission of the various maximum payloads {N 1 , N 2 , . . . N r }.
Hence, one of the results of the algorithm for determining the rate matching is to select a set, identified by JSEL, of physical resources from {1, 2, . . . r} allowing transmission of a maximum payload N JSEL and to ensure that:
∑
i
=
1
k
Y
i
=
N
JSEL
(
1
)
For this purpose, two successive phases are implemented.
In the first phase, block sizes Y′ i are determined “statically” in a similar manner to the case of the downlink. The steps of this phase are denoted by the same reference numerals as in FIG. 3 increased by 100. Hence, this is a mapping X i →Y′ i .
In a second phase, N SJEL and the Y i values corresponding to the Y′ i values are determined “dynamically” so as to satisfy equation (1). Hence, this is a mapping (Y′ 1 , Y′ 2 , . . . Y′ k )→(Y 1 , Y 2 , . . . , Y k ).
The first phase consisting of steps 400 to 408 is defined simply by the equation:
Y′ i =S Q(i) ·X i .
Next, JSEL is determined in step 410 by the following equation:
JSEL
=
min
{
j
/
∑
i
=
1
i
=
k
Y
j
′
≤
PBASE
-
LBASE
·
N
j
}
Stated otherwise, if N 1 ≦N 2 . . . ≦N r , then the smallest maximum payload allowing transmission is selected.
Then, in step 412 we define integers Z 0 , Z 1 , . . . , Z k corresponding to the value of the aggregate of the final size by:
Y i , that is to say
Z
j
=
∑
i
=
1
i
=
j
Y
i
Z 0 :=0
for i:=1 to k do
Z
i
:=
⌊
(
∑
j
=
1
j
=
i
Y
j
′
)
·
N
JSEL
∑
j
=
1
j
=
k
Y
j
′
⌋
where └x┘ is the largest integer less than or equal to x.
Lastly, the Y i are calculated simply in step 414 from:
Y i =Z i −Z i−1
In this way, it will be noted that the rounding error in calculating the final size (Y i ) is not aggregated. Thus, regardless of the number k of data blocks, only two roundings are to be carried out:
a first in respect of the value of the aggregate size denoted Z i , and
a second in respect of the value of the previous aggregate size denoted Z i−1 .
The sought-after pairs (X i , Y i ) are finally obtained in step 416 .
To summarize, in the uplink, the algorithm essentially comprises the following seven steps:
1.
for
all
the
QoS
q
do
L
q
=
⌊
(
PBASE
-
P
q
)
·
LBASE
E
q
⌋
(
step
402
)
2.
L
MAX
:=
max
q
{
L
q
}
(
step
404
)
3. for all the Qos q do Sq:=LMAX·E q (step 406 )
4. for i:=1 to k do Y′ i :=S Q(i) .X i (step 408 )
5.
JSEL
=
min
{
j
/
∑
i
=
1
i
=
k
Y
j
′
≤
PBASE
-
LBASE
·
N
j
}
Z
0
=
0
(
step
410
)
6. for i:=1 to k do for i:=1 to k do
Z
i
:=
⌊
(
∑
j
=
1
j
=
i
Y
j
′
)
·
N
JSEL
∑
j
=
1
j
=
k
Y
j
′
⌋
(
step
412
)
7. for i:=1 to k do Y i :=Z i −Z i−1 (step 414 )
To finish let us note that, although the concept of quality of service has been defined as the quality of service of a transport channel, that is to say by the quality of service offered by level 1 to the higher levels, it would be more correct, given that the object is the determination of the rate matching, to speak of the quality of service offered by the bottom of the interleaving and multiplexing chain to the channel encoder.
The embodiment presented above is not intended to limit the scope of the invention, and hence numerous modifications may (nevertheless) be made thereto without departing from the context thereof. In particular, it will be noted that the step for determining the pair of parameters {E q , P q } may be performed not only per quality of service, but also per class of coded bits for one and the same quality of service. Indeed, it is recalled that certain channel encodings (such as in particular turbocoding) deliver various classes of coded bits which are more or less sensitive to puncturing. | A method for a Code Division Multiple Access telecommunication system implemented by a mobile station. The Code Division Multiple Access telecommunication system implementing a phase of communicating data conveyed by a plurality of transport channels. The Code Division Multiple Access telecommunication system includes at least one base station and at least the mobile station with the mobile station performing a plurality of rate matching steps. Each of the rate matching steps executing a transformation of an input block of an initial size into an output block of a final size by puncturing or repeating at least one bit of the input block. | 7 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to collapsible tube supports and more particularly to a tooth paste dispenser.
Prior patents, such as U.S. Pat. Nos. 1,742,536; 1,799,678 and 2,026,864 have generally disclosed collapsible tube holders which places the paste contained by the tube under pressure with the paste being released by valve means opening and closing the ejection end of the tube.
This invention is distinctive over prior art patents by eliminatng the valve or tube closure means and in which the contents of the tube is placed under pressure sufficient to eject only a desired quantity of the paste.
SUMMARY OF THE INVENTION
A horizontally disposed rectangular flat base is transversely provided with an elongated semicircular in transverse section recess for nestng a peripheral portion of a collapsible tube having a charge of tooth paste therein with the dispensing nozzle of the tube overlying one side edge of the base. A generally U-shaped frame, having telescoping spring biased apart legs, hingedly connected adjacent the said one side edge of the base, is vertically movable about the horizontal hinge axis toward and away from the collapsible tube. The bright portion of the U-shaped frame is provided with a pressure foot member, having an arcuate surface formed on a radius complemental with the radius of the base recess, overlying the tube when the frame is manually pivoted toward the base for extruding paste from the tube in response to pressure manually applied to the frame. The frame legs are telescopically movable toward the hingedly connected end of the frame legs for progressively collapsing the tube and dispensing all of the paste therein.
The principal object of this invention is to provide a relatively simple, easily constructed holder for a collapsible tube and progressively dispensing paste contained thereby.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of the device illustrating, by dotted lines, the relative position of a collapsible tube supported thereby;
FIG. 2 is a vertical cross sectional view taken substantially along the line 2--2 of FIG. 1 when the frame is pivoted toward the base in a paste dispensing action; and,
FIG. 3 is a fragmentary vertical cross sectional view, to a larger scale, taken substantially along the line 3--3 of FIG. 1.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Like characters of reference designate like parts in those figures of the drawings in which they occur.
In the drawings:
The reference numeral 10 indicates the device, as a whole, which is rectangular flat-like in general configuration comprising a base 12 normally overlying a horizontal surface 13 and having frame means 14 hingedly connected with the base. In the example shown, the base 12 is rectangular flat-like but may be of other marginal configurations, if desired. The upper surface 16 of the base is provided with an elongated transversely arcuate recess 18 formed on a radius complemental with the periphery of a conventional paste filled collapsible tube 20. The recess 18 terminates in an abrupt shoulder 22 adjacent one side surface 24 of the base for the purpose believed readily apparent.
The base upper surface 16, in that area between the recess shoulder 22 and base side surface 24, is provided with an arcuate recess 26 for nesting a peripheral portion of the collapsible tube discharged nozzle 28. A planar platform 30 is secured to the base edge surface 24 below the position of the tube nozzle 28 for receiving any paste drippings inadvertently squeezed out of the tube.
The frame means 14 comprises a rod-like generally U-shaped member having parallel legs 32 and 34 telescopically received by a pair of casings 36 and 38 in turn hingedly connected by their end portions opposite the frame legs by hinge means 40 and 42 secured to the base adjacent its side edge surface 24 and adjacent the respective ends of the base.
As illustrated by FIG. 3, each of the casings 36 and 38 are provided with a centrally bored closed end 39 through which the respective frame leg projects. A collar 43 is secured to the leg within the casing and is vertically slidable longitudinally of the casing bore 44 toward and away from the respective hinge means. A helical spring 46 is interposed between the hinge means and the collar 42 for normally urging the frame legs toward a telescopically extended position.
Intermediate its ends, the bright portion 48 of the frame is arcuately bent outwardly in the plane of the frame legs to form a generally U-shaped handle portion 50 for vertical pivoting movement of the frame means 14 about the horizontal axis formed by the hinge means 40 and 42 toward and away from the upper surface 16 of the base, as indicated by the arrow 52. A cross member 54 is connected with the frame bight portions 48 in the plane of the frame. An elongated pressure foot member 56, semicircular in transverse section, is connected with the cross member 54 medially its end in longitudinal alignment with the longitudinal axis of the base recess 18. The arcuate surface 58 of the foot is preferably formed on a radius complemental with the radius of the base recess 18 for the purposes presently apparent.
OPERATION
In operation, the tooth paste filled collapsible tube 20 is longitudinally disposed within the recess 18 with its nozzle 28 nested by the recess 26 and with the nozzle cap, not shown, removed. The handle 50 is manually grasped and moved in the direction of the arrow 52 so that the foot member 56 overlies the closed end portion of the collapsible tube 20. Pressure manually applied to the handle 50 extrudes tooth paste 60 through the nozzle 28 onto bristles of a toothbrush, not shown, when disposed below the nozzle 28. By trial and error the user determines the magnitude of pressure to be applied to the handle 50 necessary for dispensing only a desired quantity of the tube paste 60. After the tube 20 has been collapsed and paste dispensed to the position illustrated by FIG. 2, subsequent pivoting movement of the frame means 14 to further collapse the tube 20 is achieved by manually telescoping the frame legs 32 and 34 into the casings 36 and 38 which disposes the foot member 56 toward the nozzle end of the collapsible tube 20.
Obviously the invention is susceptible to changes or alterations without defeating its practicability. Therefore, I do not wish to be confined to the preferred embodiment shown in the drawings and described herein. | A horizontally disposed base supports a collapsible tube filled with tooth paste. A frame, pivotally supported by the base, includes a pressure foot movable toward and away from the collapsible tube in overlying relation for progressively collapsing the tube and extruding paste therein. | 1 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims a benefit of priority under 35 U.S.C. §119 to Provisional Application No. 62240346 filed on Oct. 12, 2015, which is fully incorporated herein by reference in its entirety.
BACKGROUND INFORMATION
[0002] Field of the Disclosure
[0003] Examples of the present disclosure are related to systems and methods for an electrical power connector. More particularly, embodiments disclose a device that is configured transfer power through electromagnetic induction between two separable connectors, wherein the two separable connectors are coupled together by electromagnetism.
[0004] Background
[0005] Power plugs and sockets are devices that allow electrically operated equipment to be connected to a primary power supply in a building or via a generator. Electrical plugs and sockets differ in voltage and current rating, shape, size, and type of connectors. Conventional plugs and sockets operate by inserting a male connector (plugs) associated with an appliance within a corresponding female connector (sockets), which may be positioned on a wall.
[0006] Design features of plugs and sockets have gradually developed to reduce the risk of electric shock and fire. Safety measures may include pin and slot dimensions and layouts that permit only proper insertion of a plug into a socket. Further improvements to conventional plugs and sockets include grounded pins that are longer than power pins so an appliance becomes grounded before power is connected. Accordingly, to power and ground an appliance, pins associated with the plugs must directly insert into a socket, such that the pins directly contact slots associated with sockets. Thus, conventional plugs and sockets require direct physical contact to power appliances, which create risks of shock, fire, etc.
[0007] Accordingly, needs exist for more effective and efficient systems and methods for electrical power connectors where power is transferred through electromagnetic induction rather than electrical contact, which may ensure arc free and shock free use.
SUMMARY
[0008] Embodiments disclosed herein describe systems and methods for electrical power connectors where power is transferred through electromagnetic induction over a wireless connection. Embodiments may lead to a safer form of power transmission that may save lives and dollars every year. Embodiments may include a first connector and a second connector.
[0009] The first connector may be a male connector configured to connect directly with an AC supply or an adapter to a conventional wall outlet. The first connector may include an inner core with primary windings of a transformer, spring loaded lock, plate cover, grounded leads, and electrical switch. The inner core may be comprised of iron or any other material suitable for electromagnetic induction.
[0010] The second connector may be a female connector configured to be coupled with an electrical device, appliance, adapter for electrical devices, etc. The second connector may include an inner core with secondary windings, grounded leads, and a metal plate. The inner core may be comprised of iron or any other material suitable for electromagnetic induction.
[0011] Responsive to coupling the first connector and the second connector by positioning the first connector adjacent to the second connector, the plate cover may be moved and the electrical switch may be activated. The electrical switch may be activated only when the first connector and the second connector are coupled to reduce, limit, etc. overheating.
[0012] In embodiments, when the first connector and second connector are coupled together, a full transformer may be formed. The winding ratios of the inner core associated with the first connector and the inner core associated with the second connector may be between 1:1.05-1.10, such that the winding ratio of the first connector is slightly less than that of the second connector. This may ensure that any losses of power transferred between the first connector and second connector may be limited, negated, and/or minimized.
[0013] Responsive to coupling the first connector and second connector, AC current received by the first connector may induce a magnetic field in the inner core of the first connector. The induction of the magnetic field in the inner core of the first connector may induce an electrical current in the inner core of the second connector forming electromagnetic induction. Through the electromagnetic induction, power may be transferred from an electrical grid to the first connector. The power may then be transferred from the first connector to the second connector via electromagnetic induction, and from the second connector to an electrical device. Thus, the power transfer may be completed without inserting a pins associated with the first connector within slots associated with the second connector, or vice versa.
[0014] These, and other, aspects of the invention will be better appreciated and understood when considered in conjunction with the following description and the accompanying drawings. The following description, while indicating various embodiments of the invention and numerous specific details thereof, is given by way of illustration and not of limitation. Many substitutions, modifications, additions or rearrangements may be made within the scope of the invention, and the invention includes all such substitutions, modifications, additions or rearrangements.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] Non-limiting and non-exhaustive embodiments of the present invention are described with reference to the following figures, wherein like reference numerals refer to like parts throughout the various views unless otherwise specified.
[0016] FIG. 1 depicts a side cross sectional view of a device that is configured to transfer power through electromagnetic induction, according to an embodiment.
[0017] FIG. 2 depicts a top view of primary windings, according to an embodiment.
[0018] FIG. 3 depicts a side view of primary windings, according to an embodiment.
[0019] FIG. 4 depicts a top view of secondary windings, according to an embodiment.
[0020] FIG. 5 depicts a side view of secondary windings, according to an embodiment.
[0021] FIG. 6 depicts a front view of a plate, according to an embodiment.
[0022] FIG. 7 depicts an embodiment of a method utilizing a device to transfer power across two devices without voltage being transferred via a contacted wire across the devices.
[0023] Corresponding reference characters indicate corresponding components throughout the several views of the drawings. Skilled artisans will appreciate that elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions of some of the elements in the figures may be exaggerated relative to other elements to help to improve understanding of various embodiments of the present disclosure. Also, common but well-understood elements that are useful or necessary in a commercially feasible embodiment are often not depicted in order to facilitate a less obstructed view of these various embodiments of the present disclosure.
DETAILED DESCRIPTION
[0024] In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present embodiments. It will be apparent, however, to one having ordinary skill in the art that the specific detail need not be employed to practice the present embodiments. In other instances, well-known materials or methods have not been described in detail in order to avoid obscuring the present embodiments.
[0025] FIG. 1 depicts a side cross sectional view of device 100 that is configured to transfer power through electromagnetic induction, according to an embodiment. Device 100 may include a first connector 110 and a second connector 120 .
[0026] First connector 110 may be a male connector configured to be coupled with an
[0027] AC power supply of an electric grid, or be an adapter for a conventional wall outlet. In embodiments where first connector 110 is directly coupled with the AC power supply of the electric grid, first connector 110 may be recessed within a wall of a building, surge protector, power strip, etc. In embodiments where first connector is an adapter for a conventional wall outlet, pins associated with first connector 110 may be inserted into the conventional wall outlet.
[0028] First connector 110 may include primary windings 112 , plate 114 , locking mechanism 116 , switch 118 , and first end connector 119 .
[0029] Primary windings 112 may be a device that is configured to create magnetic flux in a transformer core, and create a magnetic field impinging on secondary windings 122 within second connector 120 . The magnetic field created by primary windings 112 may induce a varying electromotive force or voltage in secondary windings 122 . Utilizing Faraday's law in conjunction with magnetic permeability core properties between primary windings 112 and secondary windings 122 , first connector 110 and second connector 120 may form a transformer that is configured to transfer AC voltages between two separate and removable devices, wherein the two separate and removable devices are first connector 110 and second connector 120 .
[0030] Plate 114 may be a plate that is configured to cover a face of first connector 110 . Plate 114 may have a planar sidewall extending across the face of first connector 100 . Plate 114 may cover the face of first connector 110 to limit the exposure of primary windings 112 outside of a housing of first connector 110 . Plate 114 may also be configured to cover slot 115 positioned with first connector 110 , switch 118 , and locking mechanism 115 . In a first mode, plate 114 may be configured to be positioned planar to the face of first connector 110 when first connector 110 and second connector 120 are decoupled. Responsive to coupling first connector 110 and second connector 120 , in a second mode, plate 114 may slide within first connector 110 to be recessed within first connector 110 . Accordingly, plate 114 may be retracted within first connector 110 when first connector 110 and second connector 120 are coupled together.
[0031] Slot 115 may be a channel, groove, depression, etc. positioned within a housing of first connector 120 . Slot 115 may be shaped to receive switch 118 , such that portions of switch 118 may move in and out of slot 115 .
[0032] Switch 118 may include a first side that is configured to be positioned adjacent to plate 114 , and a second side that is configured to be positioned adjacent to locking mechanism 116 within slot 115 . In embodiments, when first connector 110 and second connector 120 are decoupled, locking mechanism 116 may apply an outward force against the second side of switch 118 . This outward force may cause switch 118 to not be fully inserted within slot 115 . For example, locking mechanism 116 may be a spring, actuator, etc. that is configured to apply mechanical force to the second side of switch 118 .
[0033] Responsive to a user coupling first connector 110 and second connector 120 by pressing second connector 120 towards the second end of switch 118 , second connector 120 may apply sufficient mechanical force against locking mechanism 118 to overcome the force applied by locking mechanism 116 to switch 118 . When overcoming the mechanical force applied by locking mechanism 116 to switch 118 , switch 118 may move along a linear path and become fully inserted within slot 115 .
[0034] Responsive to switch 118 being inserted within slot 115 , first connector 110 may complete a circuit with the power supply. When the power supply associated with the electrical grid supplies voltage to primary windings 112 , a transformer with secondary windings 122 may be formed. Alternatively, when switch 118 is not fully inserted within slot 115 , a transformer between first connector 110 and second connector 120 may not be formed. This may limit the time periods when a completed circuit with first connector 110 is formed to limit, reduce, and/or eliminate overheating of primary windings 112 .
[0035] Furthermore, responsive to first connector 110 and second connector 120 forming a full transformer, the electromagnetism forces between first winding 112 and second winding 122 may be stronger than the mechanical force of locking mechanism 116 . Thus, when the full transformer is formed, electromagnetism may unify first connector 110 and/or second connector 120 without additional coupling mechanisms.
[0036] First end connector 119 may be a contact to ground, wherein first end connector may be configured to be grounded. When first connector 110 and second connector 120 are coupled together, first end connector 119 may be directly coupled with a second end connector 129 positioned on second connector 120 . Responsive to coupling first end connector 119 and second end connector 129 , device 100 may be grounded, which may prevent a user from being in contact with dangerous voltages if electrical insulation fails, limit the build-up of static electricity when handling flammable products or electrostatic-sensitive devices, etc.
[0037] Second connector 120 may be a female connector, with a first end configured to be coupled with an electrical device, appliance, adapter for electric devices, etc. A second end of second connector 120 may be separable from first connector 110 , and may also be configured to be coupled with first connector 110 . In embodiments, second connector 120 may be configured to be inserted into a recession, perimeter, groove, etc. within first connector 110 . Responsive to positioning second connector 110 within the recession, a full transformer may be formed between first connector 110 and second connector 120 . Electromagnetic forces formed between first connector 110 and second connector 120 may be strong enough to overcome opposite forces from locking mechanism 116 . The second connector 120 may be decoupled from the first connector 110 when the circuit is formed by pulling on the second connector 120 to create forces that are greater than the electromagnetic forces.
[0038] Second connector 110 may include secondary windings 122 , second end connector 129 , and leads 124 .
[0039] Secondary windings 122 may be a device that is configured to create magnetic flux in a transformer core, which may be parred with primary windings 112 . The magnetic field within secondary windings 122 may induce a varying electromotive force or voltage in secondary windings 122 . Utilizing Faraday's law in conjunction with magnetic permeability core properties between primary windings 112 and secondary windings 122 , first connector 110 and second connector 120 may for a transformer that is configured to transfer AC voltages between two separate and removable devices, first connector 110 and second connector 120 . In embodiments, the ratio of windings between primary windings 112 and secondary windings may be 1:1.05-110. This may ensure that any loses from the transformer arrangements may be negated. However, one skilled in the art may appreciate that the ratio of the windings may be utilized to scale up or down the voltages between the connectors.
[0040] Second end connector 129 may be a contact to ground that is configured to be grounded. Second end connector 129 may be directly coupled with a first end connector 119 when second connector 120 is coupled with first end connector 110 . Responsive to coupling second end connector 129 and first end connector 119 , device 100 may be grounded, which may prevent a user from being in contact with dangerous voltage if electrical insulation fails, limit the build-up of static electricity when handling flammable products or electrostatic-sensitive devices, etc.
[0041] Leads 124 may be devices that are configured to couple secondary winding 122 with an electronical device or to a receptacle to be an adapter. Accordingly, leads 124 may be configured to transport power from secondary windings 122 to a device.
[0042] FIG. 2 depicts a top view of primary windings 112 , and FIG. 3 depicts a side view of primary windings 112 , according to an embodiment.
[0043] FIG. 4 depicts a top view of secondary windings 122 , and FIG. 5 depicts a side view of secondary windings 122 , according to an embodiment. In embodiments primary windings 112 are configured to pair with secondary windings to form a transformer.
[0044] FIG. 6 depicts a front view of plate 114 , according to an embodiment. As depicted in FIG. 6 , plate 114 may a substantially planar surface with a plurality of orifices. Two of the plurality of orifices 610 may be configured to receive secondary windings 122 associate with secondary connector 120 . A third of the plurality of orifices 620 may be configured to receive a grounded connection associated with secondary connector 120 . FIG. 7 depicts an embodiment of a method 700 utilizing a device to transfer power across two devices without voltage being transferred via a contacted wire across the devices. The operations of method 700 presented below are intended to be illustrative. In some embodiments, method 700 may be accomplished with one or more additional operations not described, and/or without one or more of the operations discussed. Additionally, the order in which the operations of method 1100 are illustrated in FIG. 7 and described below is not intended to be limiting.
[0045] At operation 710 , a first connector and a second connector may be decoupled from each other. When first connector and second connector are decoupled together, a switch within first connector may not be activated. Furthermore, when not connected, a spring within the first connector may be applying mechanical force against the switch to not allow the spring to be inserted into a slot. When the switch is not inserted into the channel, the primary windings associated with the first connector may not be receiving power from a power source.
[0046] At operation 720 , a front face of the second connector may be positioned adjacent to a front face of the first connector. Force applied by a user to second connector to front connector may slide a plate on the front face of the first connector backwards, which may insert the switch into the slot.
[0047] At operation 730 , responsive to the switch being inserted the slot, the primary windings on the first connector may receive current from a power source which may induce a magnetic field in the first connector and the second connector.
[0048] At operation 740 , the magnetic fields in the first connector and the second connector may produce sufficient force to overcome the mechanical force of the spring within the slot. Thus, the magnetic field's forces may maintain the positioning of first connector with second connector without any additional external forces.
[0049] Although the present technology has been described in detail for the purpose of illustration based on what is currently considered to be the most practical and preferred implementations, it is to be understood that such detail is solely for that purpose and that the technology is not limited to the disclosed implementations, but, on the contrary, is intended to cover modifications and equivalent arrangements that are within the spirit and scope of the appended claims. For example, it is to be understood that the present technology contemplates that, to the extent possible, one or more features of any implementation can be combined with one or more features of any other implementation.
[0050] Reference throughout this specification to “one embodiment”, “an embodiment”, “one example” or “an example” means that a particular feature, structure or characteristic described in connection with the embodiment or example is included in at least one embodiment of the present invention. Thus, appearances of the phrases “in one embodiment”, “in an embodiment”, “one example” or “an example” in various places throughout this specification are not necessarily all referring to the same embodiment or example. Furthermore, the particular features, structures or characteristics may be combined in any suitable combinations and/or sub-combinations in one or more embodiments or examples. In addition, it is appreciated that the figures provided herewith are for explanation purposes to persons ordinarily skilled in the art and that the drawings are not necessarily drawn to scale. | Embodiments disclosed herein describe systems and methods for electrical power connectors where power is transferred through electromagnetic induction. Embodiments may lead to a safer form of power transmission that may save lives and dollars every year. | 7 |
BACKGROUND OF THE INVENTION
[0001] The present invention relates to a yarn feed roller assembly for a tufting machine, and also to a method of controlling the pile height of individual stitches in a tufting machine.
[0002] U.S. Pat. No. 5,182,997 discloses a yarn feed roller assembly with two longitudinally extending drive rollers, each of which is rotated at a different speed. Associated with each end of yarn is a pivotal arm having a pair of yarn feed wheels each associated with a respective drive roller. A control mechanism is arranged to move the pivotal arm to bring one or other of the feed wheels into contact with a corresponding drive roller so that the yarn is driven by one or other of the drive rollers. When the faster drive roller is used, the yarn feed speed is high thereby tufting a high pile. On the other hand, when the low speed roller is used, the yarn feed speed is reduced and a low pile is tufted. The machine allows the pile height of each individual stitch to be controlled to be either high or low. This individual control is known as a full repeat scroll.
[0003] As a development of this, to provide greaterpatterning flexibility, a machine referred to as a three pile height full repeat scroll has been developed by the applicant. In place of the two drive rollers, this machine uses three drive rollers each of which is driven at a different speed. In a similar way, by selecting with which of the three drive rollers an end of yarn is engaged during a stitch, three different pile heights can be formed.
[0004] In order to obtain even greater patterning flexibility, it has been proposed to replace the drive and yarn feed rollers with an individual servo motor for each end of yarn. Thus, instead of three different pile heights, this machine is capable of producing a tufted carpet, in which each stitch has a pile height which can be of any height between maximum and minimum limits. However, this greater flexibility in patterning capability is extremely costly given the number of servo motors required.
SUMMARY OF THE INVENTION
[0005] According to the present invention, a yarn feed roller assembly for a tufting machine comprises a first drive roller arranged to be rotatably driven, and a plurality of actuators, each being arranged to bring an end of yarn selectively into driving engagement with the first drive roller; characterised by control means containing pattern data relating to the required pile height of each stitch, the control means being arranged to calculate from this the required proportion of the stroke for which the yarn is required to be driven by the first drive roller to achieve the required pile height, and to control the movement of each actuator so that an end of yarn is driven by the first drive roller for the required proportion of the needle stroke.
[0006] This machine provides the same patterning capabilities of continuously variable pile heights that are obtainable with the machine which has a servo motor for each end of yarn. However, it has been estimated that a machine according to the present invention can be produced for significantly less than the cost of the machine with servo motors.
[0007] In the broadest sense, the yarn is driven only by the first drive roller and is engaged with this roller for as long as is necessary to generate the required pile height. In this case, the yarn has to be gripped when it is not being driven by the drive roller to prevent the yarn from being dragged into the backing cloth by the needles. However, a preferred option is to provide a second drive roller which is arranged to rotate at a slower speed than the first drive roller, wherein each actuator is arranged to switch an end of yarn such that it is driven either by the first or the second roller to obtain the required pile height. Thus, in order to produce higher pile heights, the actuator will leave the yarn in contact with the first drive roller for a longer proportion of the needle stroke, while to produce lower pile heights, the actuator will leave the yarn in contact with the second drive roller for a longer period. The twin roller arrangement allows the yarn to be fed constantly during the needle stroke, rather than the stop/start motion provided by the single drive roller arrangement. This allows full control of the yarn during the whole needle stroke.
[0008] Although the first and second rollers allow any pile height between upper and lower limits to be produced, the invention could be performed with a yarn feed roller assembly having three or more drive rollers all driven at different speeds. The presence of more than two rollers does not allow a greater variety of pile heights to be generated. However, it will have some benefit in that it can reduce the frequency with which the actuator switches between rollers. For example, a yarn feed roller assembly with three drive rollers will be able to produce three different pile heights without having to switch from one roller to another during a needle stroke, it may be that the majority of the carpet can be produced using these three pile heights. Nevertheless,,when required, the actuators can switch the yarn from one roller to another during the needle stroke hence producing stitches with intermediate heights.
[0009] Each actuator may comprise a pivotable arm having a pair of yarn feed wheels one of which is arranged to selectively press the yarn into engagement with the first drive roller, and the other of which is arranged to selectively press the yarn into engagement with the second drive roller as the arm is pivotally moved. However, preferably, the actuator is provided by an arm having a yarn feed wheel about which the yarn is engaged, and an intermediate wheel which drivingly engages with the yarn feed wheel, the arm being movable such that the intermediate wheel can be selectively brought into driving engagement with either of the first and second drive rollers. Thus, as the yarn engages with the yarn feed wheel and not the intermediate wheel which selectively engages the two drive rollers, the possibility of the yarn being dragged as the intermediate wheel is moved from one drive roller to the other is minimized. As a consequence of this, the clearance between the intermediate wheel and the drive rollers can be reduced, thereby improving the response time of the machine and hence, the accuracy of the pile height.
[0010] In an alternative arrangement, the actuator is provided by an arm having a yarn feed wheel, the arm being moveable such that the yarn feed wheel can be selectively brought into driving engagement either with the first or second drive rollers, and means for guiding the yarn around a portion of the yarn feed wheel which does not contact the drive rollers, the yarn feed wheel having a surface which engages with the yarn so as to provide a frictional drive for the yarn. This also provides an arrangement in which the yarn is not fed between the yarn feed wheel and the driver roller.
[0011] The present invention also extends to a method of controlling the pile height of individual stitches in a tufting machine comprising, a drive roller arranged to be rotatably driven and a plurality of actuators each being arranged to bring an end of yarn selectively into contact with the drive roller the method comprising the steps of:
[0012] determining the required pile height of a particular stitch from pattern data;
[0013] determining the proportion of the needle stroke for which the yarn will need to be in contact with the drive roller to achieve the required pile height; and
[0014] operating the actuator to bring the yarn into contact with the drive roller for the required proportion of the needle stroke.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] The particular features and advantages of the invention as well as other objects will become apparent from the following description taken in connection with the accompanying drawings in which:
[0016] [0016]FIG. 1 is a schematic cross-section through a portion of a tufting machine showing the yarn feed roller assembly;
[0017] [0017]FIG. 2 is a number of diagrams (A)-(F) which show various pile heights that can be formed by the tufting machine;
[0018] [0018]FIG. 3 is a schematic cross-section showing an alternative actuator mechanism to that shown in FIG. 1; and
[0019] [0019]FIG. 4 is a schematic cross-section showing a presently preferred actuator mechanism to replace that shown in FIG. 1.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0020] In most senses, the tufting machine to which the present invention is applicable has a conventional construction. Thus, a detailed explanation of the workings of the machine will not be provided here.
[0021] The tufting machine as shown in FIG. 1 has a pair of needle bars 1 to each of which a plurality of needle modules 2 are attached. Each module 2 has a plurality of needles 3 . Conventional reciprocating mechanisms 4 are provided to reciprocate both sets of needles.
[0022] Each needle bar 1 is fed with the yarn Y from its own separate yarn feed arrangement. In FIG. 1, only the yarn feed arrangement for the left hand needle bar 1 is shown, although it should be appreciated that there is a second identical yarn feed assembly for the right hand needle bar 1 . Yarn is fed from a creel (not shown) into the yarn feed roller assembly. Yarn for the adjacent needle 3 to that shown in FIG. 1 follows a slightly different path as indicated at Y′ in FIG. 1 as is known in the art.
[0023] The yarn feed roller assembly comprises a first drive roller 5 positioned directly above a second drive roller 6 . The drive rollers extend longitudinally of the machine and will generally extend the full width of the machine, although two or more drive rollers may be provided end to end to span the full width of the machine. The first drive roller 5 is driven by a belt 7 while the second drive roller 6 is driven by a belt 8 in a known manner. The drive rollers 5 , 6 may alternatively be directly driven. The first 5 and second 6 drive rollers are arranged to be driven at different speeds. It is unimportant with this arrangement which is the faster of the two drive rollers.
[0024] The mechanism for switching the yarn between the first 5 and second 6 drive roller comprises an arm 9 which is shown in chain lines in FIG. 1, which is pivotally mounted about a fulcrum 10 towards its center. One such arm is provided for each end of yarn to feed the yarn to an individual needle. Thus, there will be a large number of arms and associated mechanisms arranged across the machine. The arm 9 as shown in FIG. 1 is in a position in which its left hand end is in its uppermost position and the right hand end is in the lowermost position. The arm 9 is biased into this position by a spring 11 which is at its minimum length. The arm is movable into its second position by means of a pneumatic actuator 12 which contacts a contact surface 13 to force the right hand end of the arm 9 upwardly against the action of the spring 11 . It should be appreciated that the pneumatic actuator can be replaced by an alternative device and may be, for example, piezo electric, electromagnetic or hydraulic.
[0025] A yarn feed wheel 14 is provided at the left hand extremity of the arm 9 . An intermediate wheel 15 positioned between the drive rollers 5 , 6 and in close engagement with the yarn feed wheel 14 . The outer surfaces of the yarn feed wheel 14 and intermediate wheel 15 are made of polyurethane rubber. Yarn feed wheel 14 is spring loaded so that it can be moved away from the intermediate wheel 15 to allow the yarn Y to be threaded round the yard feed wheel 14 . The yarn feed wheel is then returned to its operating position to nip the yarn between the yarn feed wheel 14 and intermediate wheel 15 . Thus the yarn is driven upon the rotation of these two wheels. In the position shown in FIG. 1, the left hand end of the arm 9 is in its uppermost position, in which the intermediate wheel 15 engages with the first drive roller 5 , such that the yarn Y is driven at a speed determined by the first drive roller 5 . When the pneumatic actuator 12 is actuated, the left hand end of the arm 9 is moved downwardly bringing the intermediate wheel 15 into engagement with the lower drive roller 6 , hence driving the yarn Y at a speed determined by the second drive roller 6 .
[0026] Upon leaving the yarn feed roller assembly, the yarn Y is fed through a pair of gear-type puller rolls 16 which brush against the yarn, rather than driving it, and serve to maintain the tension in the yarn while isolating the yarn feed assembly from variations in the yarn tension caused by a reciprocation of the needles 3 . The yarn then extends through a pair of guide plates 17 , 18 and then to the needles 3 .
[0027] The way in which the machine is controlled in order to produce the various pile heights, will now be described with reference to FIG. 2.
[0028] The tufting machine is provided with pattern data which contains information on the required height of each stitch of the pattern. A control means receives this data and controls the timing of actuation of the pneumatic actuator 12 accordingly.
[0029] In the following explanation, the roller 5 is the high speed roller, while the roller 6 is the low speed roller.
[0030] In order to tuft a carpet at the full pile height as shown in FIG. 2(A), the arm 9 is in engagement with the high speed roller 5 at the start of the needle stroke and remains in engagement with this roller throughout the stroke. Thus, at all times, the yarn is being fed at the fastest rate and therefore tufts at the maximum pile height (in this case 20.0 mm).
[0031] On the other hand, a carpet tufted at the lowest possible pile height is shown in FIG. 2(F). In this case, the arm 9 is in contact with the low speed roller 6 at the start of the needle stroke and throughout the stroke. Thus, at all times, the yarn Y is fed at the lowest rate hence, tufting at the lowest possible pile height (in this case, 4.0 mm). FIGS. 2 (B), to 2 (E) show four intermediate stages between these two extremes. The height of the pile is determined by the point during the needle stroke when the yarn switches from being driven by one of the drive rollers to the other. Thus, in FIG. 2(B), the control means operates to maintain the intermediate roller 9 in contact with the high speed roller 5 for 80% of the needle stroke, and switches for 20% of the needle stroke to the low speed roller 6 . In FIGS. 2 (C) to 2 (E), the portion of the time spent driving the yarn Y with the high speed roller 5 is decreased from 60% to 40% to 20% respectively, while the portion of the stroke spent driving the yarn Y with the low speed roller 6 is increased from 40% to 60% to 80% respectively.
[0032] In theory, it is possible to produce a pile height at any value between the two extremes as is shown towards the bottom of FIG. 2. However, in practice, it may be sufficient to be able to produce a number of different discrete pile heights such as the six shown in FIGS. 2 (A) to 2 (F). In practice, it is believed that between 5 and 7 different pile heights will be sufficient for most purposes.
[0033] As mentioned above, the intermediate roller 15 is moved between the high speed 5 and low speed 6 rollers. Optimum performance is achieved if this movement is done only once per needle stroke. However, there is no reason why this should not be done any greater number of times. Also, the control could be set such that the intermediate wheel 15 is moved into a default position in contact with one or other of the rollers 5 , 6 at the beginning of each stroke. However, it is preferable for a stroke of each needle to begin with the intermediate wheel 15 in the position that it was in at the end of the previous needle stroke. In particular, if the pattern data requires a number of stitches at either the maximum or the minimum pile height, there is no need to move the intermediate wheel 15 at all while these stitches are being formed.
[0034] An alternative actuator mechanism for switching between the two drive rollers 5 , 6 is shown in FIG. 3. In this example, most of the assembly is as shown in FIG. 1 including the drive rollers 5 , 6 and the spring 11 and pneumatic actuator 12 . However, in FIG. 3, the yarn feed wheel 14 and intermediate wheel 15 have been replaced by a single yarn feed wheel 20 and upper 21 and lower 22 fixed yarn guide bars. The yarn Y is fed between the upper yarn guide bar 21 and the yarn feed wheel 20 around the yarn feed wheel 20 and then between lower yarn guide bar 22 and yarn feed wheel 20 . The yarn feed wheel 20 has a grit surface which provides a frictional drive for the yarn. In common with FIG. 1, the yarn Y is not fed through the gap between the yarn feed wheel 20 and either of the driver rollers 5 , 6 . In FIG. 3, the yarn feed wheel 20 is in its uppermost position. In this position, the yarn feed wheel 20 is driven by the first drive roller 5 . In the lowermost position, the yarn feed wheel 20 is driven by the second drive roller 6 . Thus, this arrangement can be used to generate the same patterning effects as shown in FIG. 2. However, as the movement of the arm 9 opens and closes the gap between the yarn feed wheel 20 and the two yarn guide bars 21 , 22 , there is no need to provide a spring loaded arrangement as is required of the yarn feed wheel 14 in FIG. 1 as the yarn Y can be fed through the arrangement shown in FIG. 3 simply by moving the arm 9 .
[0035] [0035]FIG. 4 shows the presently preferred mechanism for the activator used to switch the yarn Y between the first 5 and second 6 drive roller. The arm 9 is moved by electric, or servo motors 30 , about the pivot or fulcrum 10 . The servo motors 30 drive pistons 32 connected to the arm to move the arm 9 about the fulcrum 10 to move the intermediate wheel 15 to contact one of the first 5 or second 6 drive rollers. The yarn feed roll 14 is illustrated as spring loaded by spring 34 in this embodiment.
[0036] Numerous alternations of the structure herein disclosed will suggest themselves to those skilled in the art. However, it is to be understood that the present disclosure relates to the preferred embodiment of the invention which is for purposes of illustration only and not to be construed as a limitation of the invention. All such modifications which do not depart from the spirit of the invention are intended to be included within the scope of the appended claims. | A tufting machine has a yarn feed roller assembly with a plurality of rotatable driver rollers driven at different speeds and a plurality of actuators in the form of a pivotable arm having in one embodiment a pair of yarn feed reels one of which is arranged to selectively press yarn into engagement with one of the drive rollers and the other arranged to selectively press yarn into engagement with another drive roller. Yarn is engaged by each actuator and a selected drive roller for a period of time determined by a pattern. The longer the actuator engages the high speed roller during the stroke of a tufting machine needle the greater will be the pile height of the tufts produced and alternatively the longer the actuator engages the lower speed roller during the needle stroke the lower will be the pile height. Pile height variations between a high pile and a low pile may be obtained by controlling the proportion of time during the stroke that the yarn engages with the high and low speed rollers. | 3 |
BACKGROUND
1. Field of the Invention
Implementations of various technologies described herein generally relate to various methods and/or systems for locating components in a Leak Detection And Repair (LDAR) program.
2. Description of the Related Art
The following descriptions and examples do not constitute an admission as prior art by virtue of their inclusion within this section.
Industrial plants that handle volatile organic compounds (VOCs) sometimes experience unwanted emissions of those compounds into the atmosphere from point sources, such as smokestacks, and non-point sources, such as valves, pumps, and/or vessels containing the VOCs. Emissions from non-point sources typically occur due to leakage of the VOCs from joints and/or seals and may be referred to herein as “fugitive emissions”. Fugitive emissions from valves typically occur as leakage through the packing set around the valve stem.
Most industrial plants have established an LDAR program to detect if any fugitive emissions are being released into the atmosphere. Given the obscure locations of many of these potential emission sources, technicians usually experience major difficulties in locating all of the LDAR components.
Further, there are security risks involved with storing the locations of hazardous gas/chemical equipment where LDAR components are positioned on an unsecured database.
SUMMARY
Described herein are one or more implementations of various technologies and techniques directed to creating, encrypting, and updating a database of position coordinates of LDAR components. In one implementation, the method for creating a database of coordinates of leak detection and repair (LDAR) components includes receiving an input pertaining to an LDAR component, obtaining position coordinates of a handheld computer device in response to receiving the input and associating the position coordinates of the handheld computer device with the LDAR component.
Described herein are also one or more implementations of various techniques for using the position coordinates to assist a user (technician) to locate an LDAR component in the field. In one implementation, the method for providing assistance to a user for locating a leak detection and repair (LDAR) component includes receiving a request to locate an LDAR component in a field, retrieving position coordinates of the LDAR component, obtaining position coordinates of a handheld computer device and providing directions from the position coordinates of the handheld computer device to the position coordinates of the LDAR component.
In one implementation, the method may further include obtaining current position coordinates of the handheld computer device when the user has reached the LDAR component, determining whether the current position coordinates are within a predetermined range of the retrieved position coordinates of the LDAR component and whether the dilution of precision of the current position coordinates are higher than the dilution of precision of the retrieved position coordinates, and if it is determined that the current position coordinates are within the predetermined range and that the dilution of precision of the current position coordinates are higher than the dilution of precision of the retrieved position coordinates, then replacing the retrieved position coordinates of the LDAR component with the current position coordinates.
Described herein are also one or more implementations of various techniques for a system for locating leak detection and repair (LDAR) components. In one implementation, the system includes one or more position coordinates satellites and a handheld computer device in communication with the position coordinates satellite. The handheld computer device includes a processor and a memory comprising program instructions executable by the processor to: receive an input pertaining to an LDAR component, obtain position coordinates of the handheld computer device using the position coordinates satellites and associate the position coordinates of the handheld computer device with the LDAR component.
In another implementation, the system includes a position coordinates satellite and a handheld computer device in communication with the position coordinates satellite. The handheld computer device includes a processor and a memory comprising program instructions executable by the processor to: receive a request to locate an LDAR component in a field, retrieve position coordinates of the LDAR component in response to receiving the request, obtain position coordinates of the handheld computer device using one or more position coordinates satellites and provide directions from the position coordinates of the handheld computer device to the position coordinates of the LDAR component.
The above referenced summary section is provided to introduce a selection of concepts in a simplified form that are further described below in the detailed description section. The summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used to limit the scope of the claimed subject matter. Furthermore, the claimed subject matter is not limited to implementations that solve any or all disadvantages noted in any part of this disclosure.
BRIEF DESCRIPTION OF THE DRAWINGS
Implementations of various technologies will hereafter be described with reference to the accompanying drawings. It should be understood, however, that the accompanying drawings illustrate only the various implementations described herein and are not meant to limit the scope of various technologies described herein.
FIG. 1 illustrates a schematic diagram of an LDAR component locator system in accordance with one or more implementations of various technologies and techniques described herein.
FIG. 2 illustrates a schematic diagram of a personal digital assistant (PDA) in accordance with one or more implementations of various technologies and techniques described herein.
FIG. 3 illustrates a flow diagram of a method for creating a database of position coordinates for LDAR components in accordance with one or more implementations of various techniques described herein.
FIG. 4 illustrates a flow diagram of a method for assisting a user to locate an LDAR component in accordance with various techniques described herein.
DETAILED DESCRIPTION
The discussion below is directed to certain specific implementations. It is to be understood that the discussion below is only for the purpose of enabling a person with ordinary skill in the art to make and use any subject matter defined now or later by the patent “claims” found in any issued patent herein.
The following paragraphs generally describe one or more implementations of various techniques directed to acquiring position coordinates of LDAR components and providing a user with a method in which to locate the immediate vicinity or the precise location of an LDAR component. In one implementation, the LDAR component locator system may include an LDAR component, a global positioning system device, one or more position coordinates satellites in communication with a PDA, a database of LDAR component information, and a database of position coordinates.
In operation, a user may perform monitoring, documenting, or maintenance work at each LDAR component. After the user has completed his maintenance work at one LDAR component, he may input an account of the work that he completed into his PDA. Upon receiving this information about a specific LDAR component, the PDA may retrieve its own position coordinates, encrypt it, and store it as the position coordinates for the specified LDAR component on a database for position coordinates. In order to keep the location of the LDAR components safe from sabotage, the component locator program may encrypt the position coordinates prior to storing them to the database. Further, the encrypted position coordinates may be stored in a database separate from the database that stores other information pertaining to LDAR components.
After an LDAR component's position coordinates have been stored, a user may request to locate the LDAR component on his PDA. Upon receiving a request to locate a specific LDAR component, the PDA may download the LDAR component's position coordinates, decrypt it, and compare it to its own current position coordinates. Using the two coordinates, the PDA may provide the user with a map or step-by-step directions on how to reach the vicinity of the specified LDAR component.
The accuracy of an LDAR component's location may be determined each time an LDAR component has been located by a user. If an LDAR component's newly acquired location coordinates are within a predetermined accuracy tolerance, the newly acquired coordinates may be stored in the database of the position coordinates in place of the previous coordinates for the LDAR component. Otherwise, if an LDAR component's newly acquired location coordinates exceed a predetermined accuracy tolerance, the PDA may display a warning notice to its user. The user may have the option to either replace the previously stored position coordinates with the newly acquired coordinates, or he may disregard the warning and keep the previously stored position coordinates on the database.
In one implementation, the component locator program may also determine the accuracy of a location by comparing the dilution of precision values between the position coordinates stored on the database and the PDA's newly acquired position coordinates. The dilution of precision may be calculated by determining the number of GPS satellites used in locating the PDA's position coordinates. If the newly acquired coordinates have a higher degree of precision than the previously stored coordinates, the component locator program may replace the previously stored coordinates with the newly acquired coordinates.
One or more implementations of various techniques for an LDAR component locator system will now be described in more detail with reference to FIGS. 1-4 in the following paragraphs.
FIG. 1 illustrates a block diagram of a system or network 100 that may be used to locate LDAR components in accordance with one or more implementations of various technologies and techniques described herein.
The system 100 may include a computer device, such as a personal digital assistant (PDA) 140 , in communication with a position coordinates satellite 110 , LDAR components 170 , a database 150 for storing LDAR information and a database 160 for storing position coordinates of the LDAR components 170 . LDAR components 170 may include devices such as valves, pumps, compressors, connectors, flanges, and other devices that can be found at industrial plants.
The PDA 140 may be configured for storing the hardware and software elements required to locate specific components. For instance, the PDA 140 may include hardware components, such as a position coordinates device 120 , and software components, such as a component locator program 130 .
The position coordinates device 120 may be used to assist position satellite 110 in obtaining the position coordinates of PDA 140 . The position coordinates device 120 may be any device that communicates with a position coordinates satellite 110 to determine its position coordinates. The satellite 110 may be configured to provide the position coordinates device 120 its position coordinates. Although only one position coordinates satellite is shown in FIG. 1 , it should be understood that in some implementations the satellite 110 may include one or more medium Earth orbit satellites. In one implementation, the position coordinates device 120 may use Global Positioning System (GPS) satellites to determine the PDA 140 's GPS coordinates. It should also be noted that satellite 110 may be replaced with other communications devices such as cellular phone towers or any other device that may be capable to provide position coordinates of the PDA 140 .
The component locator program 130 may be used to store the position coordinates of the LDAR components 170 into a database and to assist the user in locating LDAR components 170 . In one implementation, the component locator program 130 may link or associate an LDAR component 170 with its corresponding position coordinates obtained by the position coordinate device 120 . After making this association, the component locator program 130 may encrypt the position coordinates and store them in the position coordinates database 160 . The component locator program 130 may be described in more detail with reference to FIGS. 3 and 4 in the following paragraphs.
The position coordinates database 160 may be configured to store position coordinates of each LDAR component 170 . The position coordinates database 160 may be located on a server, personal computer, or other similar computer medium.
The database 150 may be configured to store LDAR component information, such as tag number, size, component type and process stream information. Like the position coordinates database 160 , database 150 may also be located on a server, personal computer, or other similar computer medium.
Although various implementations described herein are with reference to a PDA, it should be understood that in some implementations the PDA 140 may be substituted with any other computer device that can utilize software programs, communicate wirelessly with other computer media, and interface with a position coordinates device 120 , such as a laptop, Pocket PC, and the like.
FIG. 2 illustrates a schematic diagram of a PDA 200 in accordance with one or more implementations of various technologies described herein. The PDA 200 may include a central processing unit (CPU) 220 , a system memory 280 , and a system bus 240 that couples various system components including the system memory 280 to the CPU 220 . Although only one CPU 220 is illustrated in FIG. 2 , it should be understood that in some implementations the PDA 200 may include more than one CPU. The system bus 240 may be any of several types of bus structures, including a memory bus or memory controller, a peripheral bus, and a local bus using any of a variety of bus architectures. By way of example, and not limitation, such architectures may include Industry Standard Architecture (ISA) bus, Micro Channel Architecture (MCA) bus, Enhanced ISA (EISA) bus, Video Electronics Standards Association (VESA) local bus, and Peripheral Component Interconnect (PCI) bus also known as Mezzanine bus. The system memory 280 may include a read only memory (ROM) 281 and a random access memory (RAM) 283 . A basic input/output system (BIOS) 282 , containing the basic routines that help transfer information between elements within the PDA 200 , such as during start-up, may be stored in the ROM 281 . A video display 210 or other type of display device may also be connected to system bus 210 via an interface, such as a video adapter.
The PDA 200 may further include a hard disk drive 260 for reading from and writing to a hard disk. The hard disk drive 260 may be connected to the system bus 240 by a hard disk drive interface 250 . The drives and their associated computer-readable media may provide nonvolatile storage of computer-readable instructions, data structures, program modules and other data for the PDA 200 .
The PDA 200 may further include computer-readable media that may be accessed by the CPU 220 . For example, such computer-readable media may include computer storage media and communication media. Computer storage media may include volatile and non-volatile, and removable and non-removable media implemented in any method or technology for storage of information, such as computer-readable instructions, data structures, program modules or other data. Computer storage media may further include RAM, ROM, erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other solid state memory technology, CD-ROM, digital versatile disks (DVD), or other optical storage, magnetic cassettes, magnetic tape, magnetic disk storage or other magnetic storage devices, or any other medium which can be used to store the desired information and which can be accessed by the CPU 220 .
The PDA 200 may contain a communication interface 270 that may connect with other types of computer media such as servers, computers, the Internet, databases, and the like. In one implementation, the communication interface 270 may be a Bluetooth communications interface. However, it should be understood that some implementations may use other types of wired or wireless communications.
Communication media may embody computer readable instructions, data structures, program modules or other data in a modulated data signal, such as a carrier wave or other transport mechanism and may include any information delivery media. The term “modulated data signal” may mean a signal that has one or more of its characteristics set or changed in such a manner as to encode information in the signal. By way of example, and not limitation, communication media may include wired media such as a wired network or direct-wired connection, and wireless media such as acoustic, RF, infrared and other wireless media. Combinations of any of the above may also be included within the scope of computer readable media.
A number of program modules may be stored on ROM 281 or RAM 283 , including an operating system 284 , a component locator program 286 and a component information program 288 . The operating system 284 may be any suitable operating system that may control the operation of a networked personal or server computer, such as Windows® XP, Mac OS® X, Unix-variants (e.g., Linux® and BSD®), and the like. In one implementation, the component information program 288 may be stored on RAM 225 or hard disk drive 227 . The component information program 240 may be used to outline and store information about certain components such as its identification number, size, location, pressure, etc. The component information program 240 may also be configured to initiate the component locator program 286 to store or locate specific LDAR components.
The PDA 200 may further include a position coordinate device 230 , which may provide the component locator program 286 the current position coordinates of the PDA 200 . The position coordinates device 230 may include an antenna, tuned to the frequency of the position satellites, receiver processors, a clock, and other components that may be used to interface with the PDA 200 and the position coordinates satellite 110 . In one implementation, the component locator program 286 may use the position coordinates provided by the position device 230 to create a database of position coordinates for each LDAR component. The component locator program 286 will be described in more detail with reference to FIG. 3 and FIG. 4 in the paragraphs below. Although FIG. 2 indicates that the position coordinate device 230 may be integrated into the PDA 140 , it should be noted that in other implementations the position coordinate device 230 may be a separate component that communicates with the PDA 140 over the PDA's communication interface 270 .
FIG. 3 illustrates a flow diagram of a method 300 for creating a database of position coordinates of LDAR components 170 in accordance with one or more implementations of various techniques described herein. At step 310 , a user may input an LDAR component's identification information into the PDA 140 . The component's identification information may reflect its attached tag number, serial number, or any other unique identification name that may or may not be physically attached to the actual LDAR component.
Upon receipt of the component's identification information, the component locator program 286 may obtain the current position coordinates of the PDA 140 (step 320 ). In doing so, the component locator program 286 may send a command to the position coordinates device 230 to retrieve the current position coordinates of PDA 140 . Here, the position coordinates device 230 may interface with the position coordinates satellite 110 to locate and store the exact position coordinates of the PDA 140 . The obtained coordinates may be stored in memory 280 , hard drive 260 , or any other memory storage device.
Although the component locator program 286 is described as obtaining position coordinates of the PDA 140 upon receipt of the LDAR component identification information, it should be understood that in some implementations, the component locator program 286 may obtain position coordinates of the PDA 140 at times other than receiving a component's identification. For instance, the component locator program 286 may obtain position coordinates of the PDA 140 when the user performs normal maintenance operations, such as monitoring, servicing, collecting data on a specific component, and the like. The component locator program 286 may also be programmed to automatically store the position coordinates of an LDAR component when a monitoring event is recorded or when a tag is documented into the PDA. Furthermore, it should be noted that the component locator program 286 may also be configured to store the position coordinates of a specific landmark, such as a control room, intersection, or major piece of equipment.
At step 330 , the component locator program 286 associates the position coordinates of PDA 140 with the component identification information received at step 310 . In this manner, the position coordinates of the LDAR component for which the identification information is received at step 310 may be obtained.
At step 340 , the component locator program 286 may encrypt the position coordinates. In one implementation, the component locator program 286 may also encrypt the link or association between the specific component identification number and its position coordinates. Various encryption methods may be used by the component locator program 286 to keep the position coordinates of the LDAR components invisible to the public.
At step 350 , the component locator program 286 may store the encrypted position coordinates into the position coordinates database 160 . Notably, the position coordinates database 160 is separate from the database 150 that stores other information about LDAR components. The component locator program 286 may use the communication interface 270 to send the encrypted data to the position coordinate database 160 .
FIG. 4 illustrates a flow diagram of a method 400 for assisting a user to locate an LDAR component in accordance with various techniques described herein. At step 410 , the component locator program 286 may receive a request from a user to download the user's assignment.
At step 420 , the component locator program 286 may retrieve the user's assignment, the information pertaining to the LDAR components listed in his assignment from the LDAR information database 150 and the corresponding encrypted position coordinates from the position coordinates database 160 .
At step 425 , the component locator program 286 may receive a request from a user to locate a specific LDAR component from his assignment list.
At step 430 , the component locator program 286 may decrypt the retrieved encrypted position coordinates. The component locator program 286 may decrypt the encrypted coordinates using a decryption algorithm or another similar decryption method.
At step 440 , the component locator program 286 may send a command to the position coordinates device 230 to retrieve the current position coordinates of the PDA 140 . As mentioned above, the position coordinates device 230 may interface with one or more position coordinates satellites to determine the current position of PDA 140 . In one implementation, the position coordinates device 230 may store the position coordinates of the PDA 140 on some memory device that may be accessed by the component locator program 286 .
At step 450 , the component locator program 286 may use the current position coordinates of PDA 140 and the decrypted position coordinates of the specified LDAR component to provide directions from the PDA 140 's current location to the location of the specified LDAR component. The directions provided by the component locator program 286 may include a heading and distance, a general area map, a map of the area or facility in which the specified LDAR component is identified with a pointer, a snapshot view map that indicates the general direction and distance to the specified component, travelogues, vocal directions, written directions, video presentation and the like. Although it may be understood that the video display 210 may update automatically to indicate the PDA 140 's progress in reaching the specified component, it should also be noted that directions displayed on the video display 210 may not update automatically as the PDA 140 moves closer to the specified LDAR component. Instead, the user may need to enter another request to the component locator program 286 to locate the specified LDAR component, in order for the video display 210 to update. In one implementation, the actual position coordinates of the LDAR component are never displayed to the user.
Once the user has physically reached the specified vicinity of the LDAR component's location, the user may perform various tasks, such as monitor, document, collect data, and the like. Upon completion of his tasks, the user may request to update or confirm the position coordinates of the LDAR component. In one implementation, such request may take place when the user presses the ENTER key on the PDA 140 . As such, at step 460 , upon receipt of the request to update the position coordinates of the LDAR component, the component locator program 286 may once again obtain the position coordinates of the PDA 140 . In another implementation, at step 460 , upon completion of his tasks, the user may record the task that he completed into the component information program 288 . Once an LDAR component is updated on the component information program 288 , the component information program 288 may automatically send a command to the component locator program 286 to retrieve the PDA 140 's current position coordinates.
At step 470 , the component locator program 286 may compare the PDA 140 's current position coordinates recently obtained at step 460 with the previously decrypted position coordinates. Using the two position coordinates, the component locator program 286 may determine if the two sets of coordinates are within a predetermined accuracy tolerance. For example, the accuracy of the sets of coordinates may be determined by calculating the distance between the two coordinates. The predetermined accuracy tolerance may be a distance defined by the client, the user's supervisor, or the like.
At step 472 , the component locator program 286 may display a warning notice to the user if the difference between the two position coordinates exceeds the predetermined tolerance. The warning notice may be displayed on the video display 210 .
At step 474 , the component locator program 286 may prompt the user to either replace the previous position coordinates associated with the LDAR component or disregard the warning. If the user selects the option to disregard the warning, then the component locator program 286 may await for its next request to locate another LDAR component.
On the other hand, if the user selects the option to replace the previous position coordinates with the current position coordinates, then at step 480 , the component locator program 286 may encrypt and store the newly acquired position coordinates on the position coordinates database 160 . As mentioned above, the component locator program 286 may also encrypt the link between the LDAR component identification information and its newly acquired position coordinates.
Referring back to step 470 , if the difference between the two position coordinates falls within the predetermined tolerance, then at step 480 , the component locator program 286 may encrypt and store the newly acquired position coordinates on the position coordinates database 160 . In one implementation, if the newly acquired position coordinates have a higher degree of precision based on the dilution of precision value, the component locator program 286 may replace the previous coordinates with the newly acquired coordinates in the position coordinates database 160 .
Referring back to step 474 , if the user selects the option to replace the previous position coordinates with the newly acquired position coordinates, then the component locator program 286 may encrypt and store the newly acquired position coordinates on the position coordinates database 160 . After the component locator program 286 encrypts and stores the newly acquired position coordinates, it may await for its next request to locate another LDAR component.
In one implementation, the component locator program 286 may not display a warning notice at step 472 if the difference between the two position coordinates exceeds the predetermined tolerance. Instead, the component locator program 286 may report the discrepancy on a separate database for quality assurance purposes. The quality assurance information may verify whether the user was in fact in the vicinity of the LDAR component that he was monitoring, documenting, or updating.
In another implementation, the component locator program 286 may create a separate file that keeps record of the user's completed tasks. For instance, the component locator program 286 may list the LDAR component that was monitored, the time and date it was monitored, and the LDAR components dilution of precision value. Using this information, the component locator program 286 may generate information outlining the user's route/path, his pace, his activities, his periods of inactivity, and the like.
While the foregoing is directed to implementations of various technologies described herein, other and further implementations may be devised without departing from the basic scope thereof, which may be determined by the claims that follow. Although the subject matter has been described in language specific to structural features and/or methodological acts, it is to be understood that the subject matter defined in the appended claims is not necessarily limited to the specific features or acts described above. Rather, the specific features and acts described above are disclosed as example forms of implementing the claims. | Various technologies and techniques directed to creating, encrypting, and updating a database of position coordinates of LDAR components. In one implementation, the method for creating a database of coordinates of leak detection and repair (LDAR) components includes receiving an input pertaining to an LDAR component, obtaining position coordinates of a handheld computer device and associating the position coordinates of the handheld computer device with the LDAR component. | 6 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to yarn handling apparatus and more specifically to apparatus suitable for transmitting by friction a false-twist to the yarn progressing therethrough, which procedure is useful in many texturing and other applications.
2. Description of the Prior Art
The technique of applying a false twist by friction to a moving yarn has been known for a long time. The technique comprises, broadly speaking, setting the moving yarn in contact with a moving surface, displacing it transversely with respect to the path of the yarn so that the yarn is twisted upstream of where the yarn is manipulated and permitting the yarn to regain its original twist downstream thereof.
This technique, for which many applications have been foreseen, has mainly been utilized for texturing synthetic yarns. That is, by applying false-twist to such yarns while also applying a thermal heating and cooling upstream of the false-twist element, such yarn is provided with volume and elasticity.
However, other applications of using false-twist have been proposed. For example the literature suggests false twisting in the context of producing fancy yarns, yarns having alternate twists along their lengths, autotwisted yarns, and the like.
Thus, it has been proposed in U.S. Pat. No. 3,415,048 to obtain alternate twist yarns, that is, to produce yarn having successive zones with "S" and "Z" twist along the yarn length, by utilizing a false-twist spindle and by changing the twist insertion length upstream of the spindle, according to a selected frequency.
Several embodiments for providing false twist have been proposed which provide a moving surface for communicating a twist by friction to a yarn. Those presently used in the texturizing field either employ bushings against which the yarns is urged into contact (internal friction false twisting) or overlapping discs mounted on parallel axles, the moving yarn contacting the outer surface of these discs (external friction false twisting).
It has also been proposed in French Pat. Nos. 1,191,361 and 1,255,922 and in U.S. Pat. No. 2,908,133 to utilize as a means for inserting the false twist, one or several endless belts or aprons against which the yarn rubs.
As illustrated in French Pat. No. 1,147,515 (U.S. Pat. No. 2,943,433) it has been proposed to thread the yarn between two moving aprons, these aprons being arranged diagonally with respect to each other in such a way that an impulsion is conferred in the direction of their displacement during the passage of the yarn between the aprons.
However, as set forth therein, the device must operate at relatively low speed in that it is necessary, where the aprons cross, to guide them exactly according to parallel planes and to keep the aprons at a distance from one another slightly smaller than the yarn thickness for which it is desired to provide the false twist. This implies a complex apron guidance system.
Further, the aforementioned patent presents an alternate embodiment wherein the aprons are replaced by two hyperboloids which are driven in rotation, the crossing angles between the axis thereof being at an angle of between 30 and 45 degrees, the yarn passing between them along a straight line crossing both of the hyperboloid axes at equal angles.
Although the embodiment described therein appears somewhat attractive, it has the disadvantage of utilizing parts having a complicated shape, making it difficult also to feed and otherwise adjust. And, as in the case of the apron device therein described, the device is rather cumbersome owing to the fact that the two parts in between which the yarn passes are arranged one on top of the other.
Furthermore, although the contact surface of the two hyperboloids is a straight line, it is practically impossible to maintain the yarn according to such straight line, which therefore leads to a variable action of the hyperboloids on the yarn.
Finally, with regard to the superimposed crossed apron device described in that patent, it has been noticed that in normal operation, they tend to displace themselves laterally on their guide roller, which displacement, of course, disturbs their intended functioning.
Therefore, it is an object of the present invention to provide an improved and perfected device permitting the communication of false-twist by friction to a moving yarn by means of endless aprons, which have the actual advantages of the formerly proposed apron device shown in U.S. Pat. No. 2,943,433, but without the disadvantages thereof particularly owing to the fact that the invention incorporates a scheme for reducing the volume of the apparatus of the prior art device and assures a mutual contact between both aprons in a much more precise manner than theretofore achieved.
SUMMARY OF THE INVENTION
Generally speaking, the invention concerns apparatus for communicating a false-twist by friction to a moving yarn, comprising two endless aprons or belts, inclined one to the other, having two strands in mutual contact, the yarn passing between these aprons in the zone where they are in contact. In addition to providing false twist by the action occurring in the contact zone, the apparatus according to the invention permits the yarn to pass therethrough and also to permit treatment, if desired, simultaneously with the false twisting, either upstream of such action or downstream or both.
The apparatus permits, for example, appropriate associated components of equipment to wind up the processed yarn after it has been completely processed without requiring an additional step or interfering with the false twist step.
As mentioned above, associated equipment conventionally useful in treating yarn also can be employed with the apparatus herein described. Such equipment includes heater means for thermally heating the yarn either upstream or downstream of the false twist apparatus. Such a process is employed, for example, in texturing yarn.
Moreover, the apparatus for false twisting the yarn also operates in conjunction with associated equipment for varying the speed of yarn being fed through the apparatus and/or for varying the twist insertion length upstream of the false twist apparatus when it is desired, for example, to obtain a yarn presenting an alternated twist along its length.
The apparatus is useful, it should be noted, for treating filament yarn, for spun fiber yarn, or even for single rovings.
The apparatus is characterized in its preferred embodiment by having each of the aprons fitted on a pair of rollers whose diameters and positioning causes one of the aprons to operate inside of the other.
A simplified and preferred embodiment of the apparatus provides for identical guide-and-drive-roller-dimensioning for the two aprons, which provides that both the top and bottom strands of the two endless aprons to be in mutual contact. In addition, the guide rollers can be adjusted to vary the contact pressure between the aprons in the contact zone and hence consequently modify the twist given by the pressure. This can be provided by adjusting the tension of aprons and/or by slightly relocating the axis of the rollers.
Means are also provided for axially orienting the rollers with respect to each other in order to correctly center each apron.
Furthermore, to provide for precision adjustment of the contact zone, the basically cylindrical guide rollers can also be cambered by suitable and conventional means. The guide rollers are preferably arranged with their axis in the same plane, but it is permissible to modify them with respect to each other so that the apron strands in the contact zone are in suitable mutual contact.
Furthermore, the preferred embodiments of the invention contemplate that the yarn or strands of yarn be introduced in the same plane as the plane of the contact zone; however, the introduction of yarn alternatively can be introduced at a different angle. Moreover, the entry angle and the exit angle from the contact zone can be different from each other.
The apparatus described herein is shown in one of its preferred embodiments in a configuration suitable for obtaining autotwisted yarns. In such a configuration, at least two strands of yarn are guided across the contact zone in parallel fashion, each being friction twisted. A guide located downstream of the contact zone permits the joining of the processed yarn.
When the apparatus is employed in this latter application, means are associated with the aprons so that one of the yarn strands is provided with an alternate twist over its length, such means being, for example, of the type described in U.S. Pat. No. 3,415,048. One such means, for example, is a variable insertion length stop device which provides for varying the insertion length undergoing twist upstream of the contact zone.
The two aprons of the present invention form an angle related to the twist that is desired to be communicated into the yarn. Advantageously, this angle, which is conveniently defined by the angle between the displacement direction of the aprons or belts, is in excess of 90 degrees when viewed from the insertion direction of the arriving yarn. It has been determined that an angle in the neighborhood of 130 degrees is perfectly suitable when it is desired to use the apparatus for alternate twist yarns joined downstream of the aprons by autotwist. On the other hand, an angle in the neighborhood of 150 degrees is more particularly suited for communicating false twist to a single yarn.
BRIEF DESCRIPTION OF THE DRAWINGS
So that the manner in which the above-recited features, advantages and objects of the invention, as well as others which will become apparent, are attained and can be understood in detail, more particular description of the invention briefly summarized above may be had by reference to the embodiments thereof which are illustrated in the appended drawings, which drawings for a part of this specification. It is to be noted, however, that the appended drawings illustrate only preferred embodiments of the invention and are therefore not to be considered limiting of its scope, for the invention may admit to other equally effective embodiments.
IN THE DRAWINGS
FIG. 1 is a schematic representative in perspective, of apparatus in accordance with a first embodiment of the present invention in an application useful for texturing a yarn by false-twist.
FIG. 2 is a top plan view of apparatus according to the schematic view shown in FIG. 1.
FIG. 3 is a schematic representation, top view, of apparatus in accordance with a second embodiment of the present invention in an application useful for producing auto-twisted yarns.
FIG. 4 is a schematic side view of an alternate apron in accordance with the present invention fitting on its two guide rollers and including means for tensioning the apron.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Now referring to the drawings and first to FIG. 1, apparatus according to the present invention primarily comprises two endless aprons 1 and 2, whose respective upper elongate strands 3 and 4 are in mutual and parallel contact to form a contact zone therebetween. It is through the zone that the yarn is twisted in the inventive method hereinafter described. Furthermore, elongate strands 3 and 4 are positioned at an angle with one another, which is best illustrated in FIG. 2. In a preferred arrangement the angle between the aprons is established to be at 130 degrees, as illustrated.
Endless aprons 1 and 2 are respectively fitted on a set of drive and guide rollers, namely, rollers 5 and 6 for apron 1 and rollers 7 and 8 for apron 2. Further, apron 2 is positioned in such a way that it passes through or inside the center opening of apron 1. In a preferred embodiment rollers 7 and 8 are of substantially the same outer diameter as rollers 5 and 6. Hence, aprons 1 and 2 contact one another not only at their upper strands but at their lower strands, as well. Drive and guide rollers 5, 6, 7 and 8 are driven in rotation by means not illustrated and are typically arranged in a conventional manner on a supporting mount integral with a frame.
In the embodiment illustrated in FIG. 1, tension is applied to both aprons 1 and 2 by submitting one of the pair of the respective rollers guiding and driving the aprons to the outward resilient action of springs. Apron 1 is tensioned by spring 25 connected to roller 5 and apron 2 is tensioned by spring 21 connected to roller 7. Spring 25 achieves its function by being attached between a fixed point 26 and arm 24 fitted to roller 5 at one end thereof at its extremity by articulated axle 27. Tension is varied on apron 1 by the positioning of axle 27. In like manner, spring 21 achieves its function of tensioning apron 2 by being attached between a fixed point 22 and arm 20 fitted to roller 7 at one end thereof and at its extremity by articulated axle 23. Tension is varied on apron 2 by the positioning of axle 23.
The axles are adaptable for fitting with other components not shown to enable their respective positioning to be in a parallel relationship with the axis of the guide roller attached to the opposite end of the respective articulate arms. This parallel relationship maintains the correct positioning of the aprons or belts regardless of the tension setting.
Furthermore, the arrangement allows for varying lateral pressure of the apron contact apart from its effect on such pressure through stretching.
In a variation of the tensioning scheme, it can be observed in FIG. 4 that rollers 5 and 6 (and rollers 7 and 8) are alternately tensioned by an intermediate spring 30 under compression and operating to push outwardly against cooperating sliding parts 31. One of the sliding parts is attached to each of the respective rollers and they operate in a cooperating cylindrical relationship with each other to exert the pressure on the rollers. Of course, FIG. 4 illustrates a scheme for tensioning adjustments on the aprons. When this scheme is employed, and when one apron is positioned inside the other, the tensioning parts just described will have to physically accommodate to the presence of one apron encompassing the other.
Regardless of which scheme of tensioning is employed, it is possible by changing the tension on the aprons to ajust the amount of twist which is desired on the yarn in the contact zone.
Now returning to FIG. 1, yarn 9 originating from a supply not shown is delivered by a delivery device 10 in the form of cooperating endless belts or any other appropriate means and directed through the contact zone between strands 3 and 4 of the aprons. On the exit or downstream side of the contact zone, the yarn is wound up or submitted to a desirable conventional process which is compatible with the false-twist method of the present invention.
In the illustration, yarn 9 is subjected to texturing upstream of the contact zone. Delivery device 10, which can be two contiguously pressed-together belts operating around respective rollers, operates as a twist insertion locking component. That is, the twisting of the yarn is with respect to output side of device 10. Thermal treatment heater 11 between device 10 and the contact zone provides the heat treatment necessary for texturing the yarn. This heater is followed by a cooling zone 12, which may be a non-heated area or an area where the yarn is subjected to chilling below ambient temperature. Hence, it can be seen that the twist exerted on the yarn in the contact zone causes the twist to be backed up through the heater and the cooling zone. The yarn regains its original non-twist condition as it exits the contact zone.
As illustrated in FIG. 3, the apparatus just described can also be used for communicating an alternated twist to two strands of yarn 16 and 17, both of which are in motion from separate sources (not shown). On the downstream side of the contact zone, the two yarn strands are joined by autotwist.
The strands may approach the upstream side of the contact zone in a non-parallel manner. However, upstream and downstream of the aprons yarn strand 16 progresses through guides 13 and 18, respectively, and yarn strand 17 progresses through guides 14 and 19, respectively. These guides ensure that yarn strands 16 and 17 progress through the contact zone in parallel fashion. Downstream of guides 18 and 19, and preferably to one side, guide 15 provides the joining of the two yarn strands, the single autotwisted yarn being drawn therefrom as a single yarn.
In an actual application of the mode illustrated in FIG. 3, altering the twist transmitted to a strand of the yarn can be provided by changing the yarn strand delivery speed, or, preferably, by changing the twist insertion length of the strand of yarn upstream of the contact zone of the false twist device.
EXAMPLE 1
Apparatus consistent with the invention can preferably be utilized incorporating two endless aprons 1 and 2, each having a length of 28 centimeters and fitted on rollers 5, 6, 7 and 8 each having a diameter of 2.5 centimeters. The width of the aprons is 1.5 centimeters.
The aprons are each driven at a speed of 550 meters per minute, the two strands of aprons or belt 1 respectively being in contact with the respective two strands of apron 2. The angle formed between the two belts is 150 degrees.
The preferred embodiment just described is suitable for handling polyester yarn of 72 decitex, 34 filaments, at a delivery speed of 400 meters per minute.
The twist transmitted to the yarn upstream and which backs up to delivery device 10 is preferably adjusted to be on the order of 2400 turns per meter.
When the apparatus is utilized in this way, a textured yarn is obtained which has characteristics comparable to yarns textured by means of internal friction spindles. In fact, the yarn produced hereinabove can be considered to be better than such prior art produced yarn by the fact that not only do the aprons communicate a twist to the yarn but they also provide uniformity of progression.
EXAMPLE 2
The same false-twist device as shown in FIG. 1, but arranged for treating two yarn strands as shown in FIG. 3, can perferably be utilized for such yarn in the manner below. Guides 13 and 14 are positioned downstream to allow parallel spaced-apart yarns strands 16 and 17 to be at a distance from each other which is set at 10 millimeters.
Guide 15 is positioned at a distance which is 5 centimeters on the downstream side of the contact zone and the twist insertion lock or stop device for the yarn strands is located at a distance of 27 centimeters upstream of the contact zone. The progression of the yarn strand is adjusted so that it progresses through the distances just described in 0.65 seconds.
In this way, two yarn strands 16 and 17 can be delivered, each one having a core formed by a 167 decitex, 33 filament false-twist textured polyester yarn covered by 20 micron wool, the total count of each elementary yarn being of 250 decitex.
With the spacing described above, the two yarn strands are delivered at a speed of 205 meters per minute. The two aprons are run at the same speed as in Example 1.
At the exit means for the Example 2 arrangement, that is, at guide 15, an assembly yarn is obtained by autotwist of yarn strands 16 and 17, this assembly yarn presenting along its length alternate twisted zones of about 50 turns in the "Z" direction and 50 turns in the "S" direction.
The preceding examples illustrate the advantages provided by the invention and more particularly the great flexibility of the apparatus.
Furthermore, it has been observed that during a long run, with respect to apron devices in which both aprons were superimposed with respect to one another, very good lateral stability of the aprons was achieved, which also resulted in a greater regularity of the produced yarn.
Of course, the apparatus described above presents only representative preferred embodiments of the invention. Various modifications and variations to the specific embodiments will be apparent to those having ordinary skill in the art without departing from the spirit and scope of the invention. For example, the illustrations given above describe aprons having a rectangual cross-section. However, it is apparent that aprons having other cross-sectional forms can be utilized. For example, aprons having a circular cross-section can be employed, as well as aprons incorporating a plurality of elementary aprons placed side by side. Also, the yarn does not have to be fed in a plane with the contact zone, but can be fed at an angle therewith. Moreover, the exit direction of the yarn from the contact zone may be at a different angle of the yarn into the contact zone, if desired. | Apparatus including two endless aprons, one operating inside the other, the top strands thereof forming a contact zone therebetween. The aprons are angled with respect to each other preferably between 130 and 150 degrees. The yarn applied through the zone is twisted upstream of the zone with respect to a variably adjustable, insertion length stop. The yarn can be heat treated, if desired, upstream or downstream of the contact zone. Alternatively, two or more yarn strands also can be false-twisted in parallel paths through the zone and joined thereafter. By changing the length of insertion of one strand with respect to the other, alternated twist is provided to the combined yarn. | 3 |
BACKGROUND OF THE INVENTION
This invention relates in general to a diffraction grating and more particularly to a process for producing such a grating.
Electromagnetic radiation at any wavelength in the visible and near visible region of the spectrum has a tremendous capacity for transmitting information because of the extremely high frequency of the radiation. This capacity can be increased still further by multiplexing. For example, several beams of light, each of a different wavelength and modulated such that it alone is transmitting a large amount of information, may be combined at a multiplexing device and transmitted as a single beam. Various transmission mediums are available, with single mode optical fiber perhaps being the most useful for high data rates. Of course, to extract the information, the individual beams that form the multiplexed beam must be separated, and this requires a demultiplexer. A diffraction grating is suitable for this purpose, provided the spacing between the grooves of the grating varies. This causes the different wavelengths of the light beam to diffract at different locations along the grating. Thus, each of the beams can be monitored at its own location along the grating.
Holographic procedures are currently used to produce diffraction gratings on glass and other substances as well. Normally a thin layer of glass is deposited on a substrate, and then a layer of photosensitive material, called photoresist, is applied to the surface of the glass. Next, interfering coherent beams of monochromatic light are projected onto the photoresist to produce the image of a grating pattern. This exposes the photoresist which is subsequently developed to dissolve and wash away the exposed areas, leaving the photoresist with a series of alternate ridges and grooves. The grooves are, in effect, transferred to the glass layer by ion-milling which erodes both the photoresist and the glass.
The efficiency of any diffraction grating as a means for separating light of different wavelengths depends to a large measure on the depth of the grooves in the grating. Present optical irradiation procedures do not produce very deep or consistent grooves because the photoresist is not exposed uniformly. In particular, the incident light exposes the photoresist on its surface and generally uniformly throughout its depth because the photoresist is transparent. However, the incident light then reflects from the glass waveguide, as well as from the substrate, and these reflections create standing wave patterns in the photoresist. This secondary exposure destroys the uniformity of the initial exposure produced by the incident light. The distortion is such that upon subsequent development of the photoresist, the closely spaced ridges that remain are deeply undercut (FIG. 6). Indeed, the ridges are so weakened by the undercuts that they cannot withstand the development, and as a consequence they break off and wash away close to the glass film. This in turn limits the depth of the grooves that are produced during the subsequent ion-milling.
Photoresists which are less transparent to the interfering rays would of course greatly reduce the intensity of the standing waves, but these photoresists are formed from inorganic materials and are not as easily processed as organic photoresists, nor are they exposed in a uniform manner throughout their depth by the incident light.
SUMMARY OF THE INVENTION
One of the principal objects of the present invention is to provide a process for imparting a diffraction grating to a transparent waveguide with the grooves of the grating being deep enough to render the grating highly efficient. Another object is to provide a process of the type stated which is useful and effective with organic photoresists. A further object is to provide a process of the type stated which is easily and inexpensively practiced. An additional object is to provide a process of the type stated which produces a very consistent and uniform grating pattern. Still another object is to provide a diffraction grating that is ideally suited for demultiplexing signals transmitted in the visible or near visible regions of the spectrum. These and other objects and advantages will become apparent hereinafter.
The present invention resides in a process that includes applying an absorbing layer to a substance on which a grating pattern is desired, with the absorbing layer being highly absorptive to radiation at a specific wavelength. It further includes applying a photoresist layer to the absorbing layer and directing radiation of the specific wavelength at the photoresist layer to expose it in a series of closely spaced lines corresponding to the desired grating pattern. In addition, the process includes developing the exposed photoresist layer such that portions are removed to produce alternate ridges and grooves, and then removing the underlying substance at the grooves so as to transfer the grooves into that substance. The invention also consists in the parts and in the arrangements and combinations of parts hereinafter described and claimed.
DESCRIPTION OF THE DRAWINGS
In the accompanying drawings which form part of the specification and wherein like numerals and letters refer to like parts wherever they occur.
FIG. 1 is a plan view of an optical demultiplexer that includes the diffraction grating produced in accordance with the present invention;
FIG. 2 is a fragmentary sectional view of the optical demultiplexer taken along line 2--2 of FIG. 1;
FIG. 3 is an enlarged plan view of the diffraction grating;
FIG. 4 is a sectional view of the diffraction grating taken along line 4--4 of FIG. 3;
FIG. 5 is a graph showing the variances in the spacing between adjacent peaks or valleys along the diffraction grating;
FIG. 6 is an enlarged sectional view showing an exposed and developed photoresist used to form a diffraction grating by conventional procedures;
FIG. 7 is an enlarged sectional view of an exposed and developed photoresist used to form the diffraction grating according to the present invention; and
FIG. 8 is a schematic view of the optical system for exposing the photoresist.
DETAILED DESCRIPTION
Referring now to the drawings, A (FIG. 1) designates an optical demultiplexer that is useful in separating polychromatic incident light into its various components, that is wavelengths. As such, the demultiplexer A may be employed to break a multiplexed beam a of light down into beams b of monochromatic light from which it is formed. Each monochromatic beam b when modulated has the capacity for carrying a large amount of information and, by multiplexing, this capacity is increased several fold. The multiplexed beam a may be transmitted to the demultiplexer A through a single mode optical fiber 2 which is coupled to the demultiplexer A.
The demultiplexer A includes a substrate 10 (FIGS. 1 and 2) that is preferably formed from a semiconductor material such as silicon or gallium arsenide and has a plurality of photodetectors 12 integrated into it, with the detectors 12 being arranged generally in a line and spaced somewhat apart. Actually, it is desirable to have the detectors 12 arranged in groups with each group being positioned to receive diffracted light of a different wavelength, that is one of the beams b into which the multiplexed incident beam a is divided. This provides a high degree of redundancy. The detectors 12 are actually P-type dopants diffused into very shallow pockets 30 (FIG. 2) formed in the N-type substrate 10.
The substrate 10 and the photodetectors 12 which are integrated into it are covered with a buffer layer 14 (FIGS. 2 and 4) which is tapered to about 200 nm in the vicinity of the photodetectors 12 so as to pass light through it to the photodetectors 12. Where the substrate is silicon, the buffer layer 14 may be silicon dioxide having a thickness of about 1.3 μm. Other substances are suitable for the buffer layer 14 as long as they are chemically and physically compatible with the material of the substrate 10 and are further essentially transparent to each of several wavelengths into which the incident light is divided. The buffer layer 14 must also have a suitable index of refraction.
Bonded firmly to the buffer layer 14 is a waveguide 16 (FIGS. 2 and 4) which is formed from glass. Actually the waveguide 16 is a glass film having a thickness of about 0.94 μm, and that glass should have a higher index of refraction than the buffer layer 14. Of course, the waveguide 16 should be transparent to the incident light including all of the wavelengths that compose it. Corning 7059 glass is ideally suited for use in the waveguide 16, the index of refraction for that glass being 1.56, whereas the index of refraction for the silicon dioxide buffer layer 14 is 1.47.
The optical fiber 2 is coupled to the side edge of the waveguide 16, and immediately beyond the point of attachment is a thin film collimating lens 18 (FIG. 1) which directs the polychromatic beam a in a straight line which is parallel to the row of photodiodes 12, but offset to the side of them. The lens 18 may be a circularly symmetric tapered deposit of tantalum pentoxide (Ta 2 O 5 ) which projects from the surface of the waveguide 16. Similarly, ahead of each group of photodetectors 12 is a condensing lens 19 which is likewise formed from a deposit of tantalum pentoxide on the waveguide 16.
On its outwardly presented surface, the waveguide 16 possesses a diffraction grating 20 (FIG. 1) which consists of closely spaced alternate peaks 22 and valleys 24 (FIGS. 3 and 4) that are parallel and oriented at 45° with respect to the optical axis of the coolimating lens 18 so that the polychromatic beam a from the optical fiber 2 will pass through the waveguide 16 at 45° to the peaks 22 and valleys 24 of the diffraction grating 20. Measured along the optical axis, the grating 20 extends about 18 mm. The grating depth d (FIG. 4), which is the difference in elevation between the peaks 22 and the valleys 24, is at least 30 nm and is preferably greater than 40 nm. The grating period, which is the spacing c between adjacent peaks 22 or adjacent valleys 24 along the pattern 20, is not constant, but instead varies in a generally linear manner between 360 nm and 420 nm, with the smallest spacing being along that portion of the grating 20 that is closest to the collimating lens 19 (FIG. 5).
The optical fiber 2 is coupled to the side edge of the waveguide 16 such that light emitted from its end is directed to the collimating lens 18, where it is collected and projected as a thin beam a toward the area of the diffraction grating 20. Moreover, the beam a is oriented at 45° to the general direction of the peaks 22 and the valleys 24.
Upon encountering the diffraction grating 20, the beam a is diffracted and the location along the grating 20 at which the diffraction occurs depends on the wavelength of the light within the beam a. Indeed, the shorter wavelengths diffract first, since the spacing between the peaks 22 and valleys 24 is smallest in the region where the beam a first encounters the grating 20. Each wavelength which is thereafter diffracted is progressively longer. The diffraction components are separated from each other within the waveguide 16 to form separate monochromatic beams b within the waveguide 16, and each monochromatic beam b is directed toward a different condensing lens 19 and the group of photodetectors 12 that lies beyond that lens. The detectors 12 of any group monitor the beam b that is directed toward the group, converting the beam b into an electrical signal having the characteristics of the beam b itself.
Due to the unusually high grating depth d and the uniformity of the ridges or peaks 22, the diffraction efficiency is quite high, ranging between 70% and 90%. This is to be compared with a diffraction efficiency of only about 1% when the grating depth is 10 nm, even with uniform ridges or peaks 22, which in themselves have been hard to achieve with current procedures.
To produce the optical demultiplexer A, a flat semiconductor material having a thickness of about 0.625 mm is cut to the desired size and shape to provide the substrate 10. Silicon is an excellent material for the substrate 10 although other materials such as gallium arsenide, lithium niobate, and graded-index glass are also suitable.
By means of a photolithographic procedure, a series of pockets 30 (FIG. 2) are formed in the substrate 10, and the pockets 30 are arranged in arrays which correspond in position to the desired location of the photodetectors 12. Substances are then introduced into the pockets 30 to, in effect, dope the silicon substrate 10 at the pockets 30. This produces the photodetectors 12, each of which has a metallized pad 32 for conducting an electrical signal.
Next, the buffer layer 14 is formed over the substrate 10 (FIG. 7), and this layer should be a material having an index of refraction that is less than the index of refraction for the waveguide 16. Where the substrate 10 is silicon, a buffer layer 14 of silicon dioxide may be produced by heating the substrate to about 1100° C. in an oxygen-rich atmosphere. The buffer layer 14 covers not only the planar surface of the substrate 10, but the photodetectors 12 as well. The oxidation of the silicon should be sufficient to provide the buffer layer 14, which is so formed, with a thickness of about 1.3 μm.
Once the buffer layer 14 is completed, the waveguide 16 with its diffraction grating 20 is produced over it. This in itself involves several steps.
First, a suitable glass film 34 (FIG. 7) is deposited on the buffer layer 14, preferably by RF sputter deposition. The glass should have an index of refraction which is greater than the index of refraction for both the buffer layer 14 and the substance which will eventually form the other boundary of the waveguide 16, and that substance will normally be air. In the case of the silicon substrate 10 and the silicon dioxide buffer layer 14, Corning 7059 glass, which has an index of refraction of 1.56, is ideally suited for the glss film 34 of the waveguide 16. The film 34 should have a thickness of approximately 0.94 μm.
Heretofore, it has been the practice to apply an organic photoresist layer 36 (FIG. 6) directly over the glass film 34 and then expose the photoresist layer 36 with a monochromatic light projected onto the photoresist layer 36 as a grid pattern, this pattern being achieved by holographic projection techniques as will subsequently be explained. Since the photoresist layer 36 is sensitive to the light at the particular wavelength and further transparent to that light, its chemistry is changed throughout its entire depth in the exposed regions, and those regions are ideally in the areas overlying the locations at which the valleys 24 are to open out of the glass film 34. Under the conventional procedure, the photoresist layer 36 is then developed to dissolve and wash away the exposed areas of the photoresist layer 36. This leaves the glass film 34 with a series of closely spaced ridges 38 formed from the unexposed photoresist material. In this manner the underlying glass film 34 is prepared for ion milling, which is the next step of the conventional procedure.
During ion milling, the remainder of the photoresist layer 36, that is the ridges 38, and the intervening exposed areas of the glass film 34 are bombarded with ions of a suitable gas such as argon. These ions erode both the photoresist ridges 38 and the portions of the glass film 34 which are exposed between the ridges 38. As a consequence, valleys are imparted to the glass film 34 beneath the exposed regions of the photoresist layer 36, while peaks develop at the areas formerly covered by the ridges 38 of the photoresist layer 36.
By using the foregoing conventional procedure, one can obtain only a very minimum grating depth, and this imparts a very low efficiency to the diffraction grating that is so formed. Indeed, under conventional procedures, the maximum grating depth that can be achieved is about 10 nm, and this provides a diffraction efficiency of about 1%.
The problem seems to reside in the fact that the light used to expose to photoresist layer 36 not only passes into and exposes the photoresist material 36 all the way to the glass film 34, but further reflects from the glass film 34, the buffer layer 14 and the substrate 10 with an intensity nearly equal to that of the incident light falling upon the photoresist layer 36. All of this reflected radiation sets up standing wave patterns in the photoresist layer 36 in regions that are not intended for exposure. In particular, the standing waves concentrate the radiation in regularly spaced regions through the thickness of the photoresist layer 36. As a consequence, the photoresist layer 36, upon being developed is left with ridges 38 having undercuts 40 (FIG. 6) in their side walls. In other words, the ridges 38, instead of having the desired straight or uniform side walls, have undulated side walls. The undercuts 40 weaken the ridges 38 to the extent that they cannot withstand the development procedure, and as a result, the ridges 38 break off at the first or lowermost undercut 40. This leaves ridges 38 of very limited height which will not withstand sustained ion bombardment. Thus, the ridges 38 erode rapidly under the ion bombardment and the valleys 24 imparted to the glass film 34 are indeed shallow.
To overcome the foregoing problem and thereby significantly increase the grating depth, an absorbing layer 42 (FIG. 7) that is capable of absorbing much of the radiation cast upon it in the holographic exposure, is interposed between glass film 34 and the photoresist layer 36. Where the exposure is achieved with violet or near violet radiation, iron oxide (Fe 2 O 3 ) is ideally suited for use as the absorbing layer 42 because it absorbs strongly in the violet region of the spectrum. The iron oxide is applied to the glass film 34, preferably by vapor deposition, and the application should be of sufficient duration to provide the absorbing layer 42 that is so formed with a thickness of about 200 nm. A reactive deposition from oxygen and bubbled vapor of iron pentacarbonyl of 3 minutes duration of 90° C. affords a suitable iron oxide absorbing layer 42. The layer 42 may also be deposited by sputtering from an iron oxide target.
Once the absorbing layer 42 is deposited, it is in turn coated with a photoresist layer 36 (FIG. 7) which is the same organic material used in the photoresist layer 36 of the conventional process (FIG. 6). A suitable material for the layer 36 is Shipley AZ-1350B positive photoresist which is quite sensitive to radiation in the violet region of the spectrum and is also quite transparent to that radiation as well, so that it will expose uniformly throughout its depth. This material should be applied in a quantity sufficient to provide the photoresist layer 36 with a thickness of at least 190 nm, and preferably more.
Next, the photoresist layer 36 is exposed by projecting an image of the grating pattern 20 upon it. The light that casts the image should of course contain a bandwidth to which the photoresist material of the layer 36 is sensitive, and should further not contain any bandwidths to which the absorbing layer 42 is either highly reflective or transparent. Where the photoresist layer 36 is Shipley AZ-1350B positive photoresist and the absorbing layer 42 is iron oxide, monochromic violet beams, such as emitted from a krypton laser, are ideally suited for exposing the photoresist layer 36.
To derive the image of the diffraction grating 20, a single monchromatic beam 46 (FIG. 8) is split into two beams 48 and 50 which are then caused to interfere at the face of the photoresist layer 36 to form a holographic image or hologram consisting of closely spaced lines. More specifically, the single violet beam 46 is derived from a laser 52 which projects the beam 46 through a lens 54 and onto a half-silvered beam splitter 56 which divides the single beam 46 into two separate beams 48 and 50, the former of which is generally coincident with the original beam 46 while the latter is at a right angle.
The coincident beam 48 passes through an adjustable iris diaphragm 58 to a mirror 60 which reflects it to a pinhole spatial filter 62 that removes shadows and causes the generally narrow beam 48 to spread. The beam 48 thereupon passes through a cylindrical lens 64 which causes it to converge slightly. The lens 64 has an antireflective coating and the peripheral portions of its forward and rear faces are obscured by masks 66, all to prevent unwanted reflections.
The other beam 50 likewise passes through an adjustable iris diaphragm 68 to a mirror 70 where it is reflected to a pinhole spatial filter 72 that spreads it and also removes shadows. The arrangement is such that the coherent beams 48 and 50 emerging respectively from the lens 64 and the spatial filter 72, interfere at the exposed face of the photoresist 36 to produce a holographic image of closely spaced alternate lines of illumination and darkness. The illuminated lines, of course, expose the photoresist layer 36. To further prevent unwanted reflections, another black mask 74 is positioned opposite and generally parallel to the photoresist layer 36, but out of the beams 48 and 50. The presence of the cylindrical lens 64 causes the spacing between illuminated lines to vary along the image that is cast.
The closely spaced thin lines of light pass through the generally transparent layer of photoresist 36, and thereby expose it uniformly throughout its depth. However, upon encountering the absorbing layer 42, practically all of the radiation is absorbed. Very little reflects from the absorbing layer 42 and still less passes through it to be reflected back from the glass film 34, buffer layer 14, and substrate 10. Consequently, the magnitude of standing waves in the photoresist layer 36 is greatly diminished, and the exposure occurs in a uniform manner throughout the depth of the photoresist layer 36.
After the photoresist layer 36 is exposed, it is developed by immersing it in a suitable solution that loosens and washes away the regions exposed by the light. The resulting structure is a series of closely spaced ridges 80 (FIG. 7) composed of unexposed photoresist material and a series of voids 82 separating the ridges 80. The ridges 80 extend substantially the full height of the original photoresist layer 36 and have straight side walls which impart uniform width to the ridges 80. The voids 82 extend downwardly to the absorbing layer 42 which is exposed at the base of each void 82.
Next the surface composed of the closely spaced ridges 80 and intervening voids 82 is subjected to a bombardment of ions, with the intensity of the bombardment being sufficient to erode both the ridges 80 remaining from the photoresist layer 36 and the absorbing layer 42 between the ridges 80, as well as the glass film 34 that underlies the absorbing layer 42. This is known as ion milling and it continues long enough to completely erode the ridges. As a result, the grating pattern of the photoresist layer 36 is transferred into the glass film 34 in the form of the peaks 22 and valleys 24. Argon-ion milling performed with a Commonwealth Scientific Millatron IV system is suitable.
Any of the photoresist layer 36 that remains after the ion milling is removed either with a chemical stripper or by ashing in an oxygen plasma. Any iron oxide that remains from the layer 42 after the ion milling is removed from the glass film 34 with a hydrochloric acid solution. This does not harm the glass film 34, the silicon dioxide buffer layer 14, or the silicon substrate 10.
Since the ridges 80 at the outset of the ion milling are the full height of the original photoresist layer 36, as opposed to being of very limited height as in the case of the conventional procedure, the ion milling can continue for a substantially longer period of time, and this results in a significantly greater grating depth d. Whereas the grating depth achieved by the conventional procedure is no more than about 10 nm, grating depths d as high as 40 to 50 nm are possible with the improved process that utilizes the absorbing layer 42. Moreover, the absence of reflections during the exposure of the photoresist layer 44 results in peaks 22 which are for all intents and purposes continuous throughout the entire width of the diffraction grating 20. This coupled with the substantial depth of the grating 20 provides a large area with very high diffraction efficiency.
Finally the lenses 18 and 19 (FIG. 1) are formed on the exposed surface of the glass film 34 outside of the area occupied by the diffraction grating 20. This may be achieved by masking the glass film 34 to cover all of it except the specific locations where the lenses 18 and 19 are desired and then sputtering a suitable lens substance such as tantalum pentoxide (Ta 2 O 5 ) onto the exposed surface of the glass film 34. This completes the production of the waveguide 16.
The diffraction grating 20 which has been described is particularly adapted for use in a demultiplexer, such as the demultiplexer A. However, the process for producing the diffraction grating A may also be employed for diffraction gratings designed for a wide variety of uses.
This invention is intended to cover all changes and modifications of the example of the invention herein chosen for purposes of the disclosure which do not constitute departures from the spirit and scope of the invention. | A diffraction grating is formed by depositing a glass film on a substrate and thereafter applying to the glass film a layer that is highly absorptive to radiation of a specific wavelength. The highly absorptive layer is then coated with a photoresist that is transparent and photosensitive to light of the specific wavelength. Next the photoresist layer is exposed with a holographic image of a desired grating pattern, and the exposed areas are carried away in a developing solution, leaving the photoresist with a grating pattern consisting of a series of closely spaced ridges separated by voids. During the exposure of the photoresist, the absorbing layer absorbs most of the radiation that penetrates the photoresist and thereby prevents that radiation from reflecting from the glass layer or the substrate and creating a pronounced standing wave pattern. A wave pattern of that nature would expose the photoresist in undesired areas, resulting in weakened ridges during the subsequent development. By reducing the standing waves, unusually high ridges are obtained. Thereafter, the deep grating pattern is transferred to the glass film by ion-milling the exposed surface of the photoresist. This erodes both the photoresist and the glass film, and due to the deep grating pattern in the photoresist, the grooves imparted to the glass film are also quite deep. The greater depth of the grooves in the glass significantly improves the diffraction efficiency. | 8 |
BACKGROUND OF THE INVENTION
The present invention relates to a device magnetically holding sockets in an original and convenient sequence. In the past, socket heads have been stored in a haphazard fashion in a tool box or drawer resulting in misplacement or loss of tools. Socket heads have also been magnetically affixed to a clumsy oversized holder. The storage of socket heads, as known, has not enhanced the ease of use of the sockets by an individual. Individuals frequently become frustrated due to their inability to identify, locate, retrieve, and or use a particular socket at the time of demand.
Devices for magnetically holding socket heads are known in the art. For example, U.S. Pat. No. 3,405,377, issued Oct. 8, 1968, discloses a magnetic holder having sockets extending vertically downward into the device. U.S. Pat. No. 5,080,230, issued Jan. 14, 1992, discloses a magnetic holder having a plurality of bores for vertical receipt of a particular sized socket. U.S. Pat. No. 4,802,580, issued Feb. 7, 1989, discloses a magnet mounted inside a pair of spaced armature plates for holding sockets. None of these devices provides enhanced magnetic attraction properties while simultaneously minimizing size of the holder, and maximizing visibility of the individual sockets.
SUMMARY OF THE INVENTION
The invention relates to a device for magnetically holding sockets in a desired horizontal sequence. One embodiment of the device is substantially rectangular having a plurality of parallel channels of descending circumference adapted to receive corresponding socket heads from a standard or long socket set. The device promotes a plurality of magnetic arcs, having pole lines parallel to the channels, for engagement to the exterior of the cylindrical sockets. The magnetic attraction properties of the device offer a significant improvement over the prior art while simultaneously providing maximum visibility of the socket heads which facilitate retrieval by an individual.
It is a principal object of the present invention to provide a new and improved holder for socket heads of relatively simple and inexpensive design, construction, and operation which is convenient in size, safe, durable, well-organized, and which enhances an individual's ability to retrieve an individual socket head upon demand without fear of damage to the holder or loss of the socket.
Another object of the invention is to maximize the magnetic attraction properties of the holder for engagement of a set of sockets, while simultaneously maximizing visibility of the sockets, thereby facilitating retrieval by an individual.
Still another object of the invention is to provide a magnetic holder of sockets, minimizing the risk of misplacement or loss of sockets, due to involuntary disengagement of socket heads from the holder upon accidental impact of either the holder or the sockets with an object.
Still another object of the invention is provide a magnetic holder of socket heads of convenient size for efficient use within a tool drawer, chest, and/or box.
Still another object of the invention is to provide a magnetic holder of sockets of simple organizational structure defining channels of descending circumference which facilitates identification of the sockets and their use by an individual.
A feature of the present invention is a plurality of parallel and recessed channels of descending circumference, sized to horizontally receive corresponding socket heads of a standard or long socket set.
Another feature of the present invention is an aperture traversing each channel.
Still another feature of the present invention is a magnet affixed to the holder opposite the channels, and proximal to the apertures, which defines a plurality of magnetic pole lines parallel to the channels adapted for horizontal engagement of either long or standard socket heads.
Still another feature of the present invention is the ability of the magnet to simultaneously attract socket heads for engagement to the device, and position the device in a desired location on a surface.
Still another feature of the present invention is the definition of a series of magnetic arcs of descending circumference which are specifically adapted for receiving engagement of a corresponding socket head.
Still another feature of the present invention is the ability of the plurality of magnetic arcs to establish magnetic circuits upon engagement of the magnetic arcs with the exterior of the socket heads within the device.
Still another feature of one embodiment of the present invention is the ability to separate the socket holder from the base providing flexibility to an individual with respect to positioning and/or relocation of the device.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an exploded isometric view of the invention showing the magnet separated from the holder.
FIG. 2 is a cross-sectional view of the invention and socket heads taken along line 2--2 of FIG. 1.
FIG. 3 is a cross-sectional view of the invention and socket heads taken along line 3--3 of FIG. 1.
FIG. 4 is an isometric view of the bottom of the invention without the magnet.
FIG. 5 is an exploded isometric view of an alternative embodiment of the invention.
FIG. 6 is a cross-sectional view of an alternative embodiment of the invention and socket heads taken along line 6--6 of FIG. 5.
FIG. 7 is a cross-sectional view of an alternative embodiment of the invention taken along line 7--7 of FIG. 5.
FIG. 8 is an expanded bottom view of an alternative embodiment of the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Two forms of the invention are illustrated and described herein. The socket holder is indicated in general by the numeral 10 and socket head is indicated in general by the numeral 5.
In general, the socket holder 10 is rectangular in shape and molded of one-piece construction from plastic or polypropylene material. (FIG. 1) The length of the socket holder 10 may vary to suitably hold any desired number of socket heads 5 ranging from six to thirty-six in number. The width of the socket holder 10 may vary to hold standard, or long, sized socket heads 5. The socket holder 10 is of a convenient size to easily fit into a tool chest, box, or drawer while holding a set of socket heads 5.
One embodiment of the socket holder 10 includes a pair of parallel sidewalls 12 and a pair of parallel end walls 14 as shown in FIGS. 1-4. An opposite pair of interior walls 18 traverse the entire length of the bottom of the socket holder 10, between the pair of end walls 14 and parallel to the pair of sidewalls 12. (FIG. 4) The pair of interior walls 18 define a cavity 20 suitably adapted for receiving engagement of a magnet 22. (FIG. 1)
The socket holder 10, including the pair of sidewalls 12 and pair of end walls 14, generally define the area for magnetically holding a plurality of substantially cylindrical socket heads 5.
A plurality of ridges 24 are generally perpendicular to the pair of sidewalls 12 and are parallel to the pair of end walls 14. The ridges 24 are preferably molded into the socket holder 10 during construction. The ridges 24 are generally spaced to define a desired number of channels 26 of either descending or ascending circumference. The channels 26 are recessed below the top edge 27 of the sidewalls 12 and define the location for horizontal receiving engagement of the socket heads 5 of corresponding circumference. The ends of the channels 26 are defined by the sidewalls 12. The channels 26 are semicircular in shape (FIGS. 1, 2 AND 6).
The channels 26 significantly improve the visibility of the socket heads 5 from at least two directions. First, the socket heads 5, may be viewed along the ends as seen in FIG. 2. The parallel, organized, sequential arrangement of the socket heads 5, by descending circumference, significantly enhance an individuals ability to retrieve a particular size socket upon demand. Second, the socket heads 5 may be viewed along the length of the cylindrical sockets. The horizontal positioning of the socket heads 5 maximizes the visibility of any and all marking indicia located along the exposed length of the tool. The ease of identification and retrieval of a particular socket head 5 is thereby significantly enhanced in comparison to the prior art.
An aperture 28 preferably traverses each channel 26 proximal to the bottom of the socket holder 10. (FIGS. 1, 2) Generally, the apertures 28 are rectangular in shape; however, the apertures 28 may be of any preferred shape including but not limited to square, round, or oval at the discretion of the individual. The apertures 28 permit direct magnetic attraction between the magnet 22, positioned in the cavity 20, and the socket heads 5 located in a corresponding channel 26.
A magnet 22 is preferably inserted into and affixed to the cavity 20 of the socket holder 10 below the apertures 28. The magnet 22 preferably contacts a socket head 5 through the aperture 28 along a portion of the cylindrical exterior of the socket head 5. (FIG. 3) Preferably the magnet 22 is formed of one piece construction from a flexible strip of material formed with magnetic material imbedded in non-metallic binding material as known in the art. An example of the material forming the magnet 22 is a NITRILE rubber binder material having imbedded therein strips or rows of magnetic particles. This material is commercially available from Minnesota Mining and Manufacturing Corporation. Alternatively, the magnet 22 may be formed of a series of horizontally positioned magnet pieces 23. (FIG. 1) The magnet pieces 23, following horizontal alignment, are preferably of the same dimensions as a one piece magnet 22. The magnet pieces 23 may be affixed together along the edges of each individual magnetic piece 23, by use of adhesives, so long as the magnetic forces of the magnet 22 are not affected.
The magnet 22 is affixed to the socket holder 10 by any preferred means, including but not limited to flanges located on the sidewalls and end walls 12 and 14, respectively, and/or adhesives attaching the magnet 22 to the bottom of the socket holder 10.
A plurality of pole lines 29, in the preferred embodiment, are specifically directed perpendicular to the sidewalls 12. A pole line 29 centrally traverses each aperture 28 of each channel 26 of the socket holder 10. The pole lines 29 define the magnetic arcs of the magnet 22 for engagement to the exterior of the socket heads 5. The magnet 22 may be polarized to define pole lines 29 in a specific desired direction or location to suit the individual needs of a user. A magnet 22 having pole lines 29 centered within the apertures 28 focuses the magnetic attraction forces of the magnet 22 along the line of contact between a horizontally positioned socket head 5 within a channel 26, and the magnet 22. Preferably the line of magnetic force for the magnet 22 is focused along the pole lines 29 for engagement to a socket head 5.
Improved engagement between the socket holder 10 and the socket heads 5 occurs due to the increased exterior surface area of the socket heads 5 in magnetic contact with the magnet 22. The improved magnetic attraction promotes utility of the invention by minimizing undesired separation of the socket heads 5 from the socket holder 10.
The magnet 22 is generally of sufficient strength to affix and hold a socket holder 10, containing numerous socket heads 5, in a particular location upon a surface during use.
In operation, sequential organized positioning of socket heads 5 of a socket set significantly enhances the retrieval of a particular socket head 5 upon demand by an individual. The socket heads 5 are held in a preferred position by the pair of sidewalls 12, ridges 24 which define the corresponding channel 26, apertures 28, and magnet 22.
One side of the magnet 22 is exposed through the apertures 28 for engagement to the socket heads 5 (FIG. 1). The opposite side of the magnet 22 is also exposed over its entire length for engagement to a metallic surface such as a tool bench. The exposure of an entire surface of the magnet 22 opposite the channels 26 provides the means for placement of the socket holder upon a vertical, horizontal, inclined, and/or inverted surface. The magnetic attraction forces exerted upon the socket heads 5 by the magnet 22 significantly exceed the force of gravity acting on the socket heads 5. Involuntary separation of the socket heads 5 from the socket holder 10 during inverted positioning of the holder 10 is thereby prevented. In addition, the magnetic attraction forces of the magnet 22 are of sufficient strength t prevent involuntary separation of the socket heads 5 from the socket holder 10 upon accidental impact between the socket holder 10 and an object. The magnetic positioning of the socket holder 10 upon a surface, eliminates the cumbersome attaching of a device by the use of screws, bolts and nuts, and/or adhesives.
An alternative embodiment of the invention is illustrated in FIG. 5. This embodiment is formed substantially of metal components. The socket rack 30, shown in FIG. 5, in general includes a pair of parallel barriers 32, a plurality of parallel troughs 34, and a substantially square magnet 36. The plurality of parallel troughs 34 are preferably milled into the pair of barriers 32 as known in the art. Preferably the barriers 32 are formed of metal. The troughs 34, like the channels 26, are aligned and of descending circumference as earlier described. One noticeable distinction of the troughs 34 is the absence of apertures. In this embodiment, the area below the troughs 34 is substantially open and adapted for receiving engagement of a square magnet 36 as shown in FIGS. 5 and 7. A pair of channel flanges 38 diverge outwardly, substantially perpendicular from the lower portion of the pair of barriers 32 opposite the troughs 34 (FIG. 5). The channel flanges 38 provide the means for engagement of the socket rack 30 to the base indicated in general by the numeral 40. As seen in FIG. 8, the outwardly extending channel flanges 38 are proximal to the substantially open bottom of the socket rack 30. The square magnet 36 is preferably held into position within the socket rack 30 by at least one centrally located bridge 42 extending laterally between the pair of barriers 32 proximal to the channel flanges 38 (FIG. 8). In this embodiment, preferably a bridge 42 is also positioned at each oppositely divergent end of the socket rack 30 (FIGS. 5, 8).
The base 40 is generally rectangular, preferably having the same length as the socket rack 30. The base 40 is preferably wider than the extending channel flanges 38. The base 40 has a pair of opposite channel guides 44. Each channel guide 44 initially extends vertically upward from the base 40, then extends horizontally inward, centrally converging toward each other, to define the pair of channel guides 44. The pair of channel guides 44 are adapted for sliding and receiving engagement of the pair of channel flanges 38, which affix the socket rack 30 the base 40 (FIGS. 7 and 8).
Preferably a second flat rectangular magnet 46 is affixed to the base 40 opposite the channel guides 44. The second magnet 46 may be affixed to the base 40 by any conventional means including but not limited to adhesives.
The square magnet 36 is generally positioned in contact with the barriers 32 and is retained in position by the bridges 42. The top of the square magnet 36 preferably is below the troughs 34 over the entire length of the socket rack 30. The base 40, having the second flat magnet 46, provides an individual with the ability to temporarily separate the socket rack 30 from the base 40 for transportation to a desired location. The second flat magnet 46 also provides an individual with a convenient means for relocation of the base 40 and the socket rack 30 to a desired position, thereby significantly improving the utility to an individual. The second flat magnet 46 is preferably adapted for mounting the base 40 and the socket rack 30 to a desired inclined, vertical, horizontal, or inverted surface.
The square magnet 36 and the second flat magnet 46 of this embodiment are generally constructed of the same material as earlier described. The square magnet 36 of this embodiment has pole lines which are substantially parallel to the pair of barriers 32 and perpendicular to the troughs 34. In this embodiment, the engagement between the square magnet 36 and the metallic barriers 32 enhance the attraction forces of the magnetic arcs as known in the art. The magnet arcs of the square magnet 36, in conjunction with the troughs 34 significantly improve the engagement between the metallic cylindrical socket heads 5 and the socket rack 30 over the known art. The square magnet 36 and the second flat magnet 46 of this embodiment encompass the features, functions, advantages, attributes, and purpose of the alternative embodiment, as previously described, which in all remaining respects are identical to each other.
The aligned troughs 34 are also preferably adapted to horizontally receive socket heads 5 of corresponding circumference. The troughs 34 of this embodiment encompass the features, functions, advantages, attributes, and purpose of the alternative embodiment as previously described, which in all remaining respects are identical to each other.
This embodiment may also vary in size and width as earlier described. In addition, this embodiment encompasses the functions, advantages, attributes, and purpose of the alternative embodiment as previously described, which in all remaining respects are identical to each other.
The present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof; therefore, the illustrated embodiment should be considered in all respects as illustrative and not restrictive, reference being made to the appended claims rather than to the foregoing description to indicate the scope of the invention. | The invention relates to a device for magnetically holding sockets in a desired horizontal sequence. One embodiment of the device is substantially rectangular having a plurality of parallel channels of descending circumference adapted to receive corresponding socket heads from a standard or long socket set. The device promotes a plurality of magnetic arcs, having pole lines parallel to the channels, for engagement to the exterior circumference of the cylindrical sockets. The magnetic attraction properties of the device offer a significant improvement over the prior art while simultaneously providing maximum visibility of the socket heads which facilitate retrieval by an individual. | 8 |
FIELD OF THE INVENTION
[0001] The present invention relates generally to the syncing of a linear event with a nonlinear event and more particularly for the syncing of digital video files to a live performance.
BACKGROUND OF THE INVENTION
[0002] Syncing digital media to performances in music concert settings is not a new practice. Sync methods have been developed in the club scene, the classical concert hall and other music venue types. Existing sync methods generally fall into the following categories:
1. Scrubbing. Scrubbing is a well-known audiovisual editing technique that allows an individual to increase or decrease playback rates of digital files. Scrubbing is most often accomplished manually as a way to achieve a rough, imprecise sync so no particular consideration is given to matching rhythmic cue points. As a result this approach is not well suited to produce a full and careful sync. 2. Beat Matching. Beat matching is a method that has been used in dance clubs by disk and video “jockeys” for many years. This method could be described as a more sophisticated form of scrubbing where the digital media to be synced is mapped to the beat or pulse of a second media file. In this method playback of the first media file is stretched or condensed to sync the downbeats of the two media files in an attempt to seamlessly blend the tempo of the two. The drawbacks to this method are that one needs to pre-set the beat sync before the live performance since there is no completely efficient way to accomplish this function in real time. This method assumes that tempo of the video will remain unchanged, with the operator adjusting the playback rate of the audio files to match the video. 3. Click Tracks Click tracks have been used in soundtrack recording sessions for many years and have more recently been adapted for use in live concert performances. The “click” is an audio metronome embedded in the media file to be synced. The “click” is fed through earpieces to the musicians who essentially play along to the tempo they hear. The audience never hears the “click” and so long as the musicians stay “on the click” the sync between digital file and live performance will be perfect. 4. Video Chapters. During the editing process the video file is divided into chapters with new chapters beginning at assigned cue points in a musical score. When the live performance reaches a cue point the video file is advanced to the next chapter, either manually or by a computer process designed to identify the cue points through pitch recognition or some other score reading technique. Video chapters have also been used to sync movie files to music.
[0007] In each category above, the sync achieved is either very imprecise and or it requires pre-recorded music with a perfectly steady beat such as computer generated “techno” music. Also, none of the foregoing methods are satisfactory in the situation where a live performance of a piece of music, a play, a dance or the like is to be precisely synced with a digital media file. The problem stems from the fact that no two live performances of the same piece are the same due to inherent tempo variations that occur, and this result holds true even if performed by the same individuals. These tempo variations occur because human beings are not capable physiologically of performing with the millisecond precision of a digital timing device, and due to the fact that artists will purposefully and for artistic effect increase or lower the tempo of a particular section of the live performance. However, a pre-recorded audio or video track is an invariable replica of one particular performance with all of its particular intrinsic tempo variations. As a result, pre-recorded audio or visual tracks will invariably become out of sync with live performances as a joint performance thereof proceeds.
[0008] What is missing is a system that provides for a way of syncing a live performance with all of its inherent variability with a static digital video file. However, each existing method described above fails because the approach focuses on trying to match the live performance to the invariable recorded work, and generally lacks in precision, flexibility, artistry or a combination of thereof. Thus, prior art syncing techniques fail to provide for the needed fluidity, flexibility and accuracy required for transitions from one tempo to the next and/or from one musical section to the next. Prior art syncing techniques can allow for some rate variations, but only where they are very small, and/or very infrequent or also require that the tempo is set or determined by the recorded media, not the live performance.
SUMMARY OF THE INVENTION
[0009] The present invention comprises a new approach to syncing of a prerecorded video media file with a live performance. In the present invention, unlike the prior art, the live performance dictates the tempo and transition changes and provides for adjusting the playback rate of the fixed recorded media accordingly. In most cases the video file represents a video recoding to which music has been previously adapted, as for example Disney's® Fantasia®. Of course, the original sound recording has its own unique tempo on a microsecond basis and was edited along with the animation to produce a well timed finished work. If a conductor or musical group would like to play the same music live along with a projection of that animated piece, with the original soundtrack thereof muted, then the playback rate of the video must be adjustable to fit the tempo of the live performance which will inevitably be different from the original.
[0010] Such control is provided by a control device, such as a tablet computer, that is connected wirelessly or by wire to another separate computer containing software specifically designed to vary the rate of playback of the prerecorded media, based upon input therefrom. The controller is operated by an individual who has a full and detailed view of the live performance. Thus, in the case of an orchestra playing with a pre-recorded video, the operator of the controller may be in the orchestra with a close connection to the musicians and in direct sight of the conductor. The controller includes a slide bar function comprising an actual mechanical or virtual slide switch/button that the operator can move back and forth thereby advancing or retarding the playback of the video. In the hands of a skilled operator the controller becomes somewhat of a musical instrument that the operator “plays” to achieve the desired syncing effect. This approach provides orchestras and the like with a much wider range of artistic control and possibilities for syncing with a full range of pre-recorded works.
DESCRIPTION OF THE DRAWINGS
[0011] FIG. 1 shows a standard concert hall performance setting.
[0012] FIG. 2 shows a basic data flow overview.
[0013] FIG. 3 shows an example of a controller/user graphical user interface.
[0014] FIG. 4 shows a detailed view of the tempo adjustment window of FIG. 3 .
[0015] FIG. 5 shows a detailed view of the visual alignment window of FIG. 3 .
[0016] FIG. 6 shows a detailed view of the section marker table of FIG. 3 .
[0017] FIG. 7 shows a basic software flow and control chart.
[0018] FIG. 8 : shows a detailed view of the software flow and control chart of the synchronizer of FIG. 7 .
DETAILED DESCRIPTION OF THE INVENTION
[0019] As seen by first referring to FIG. 1 , a concert hall is shown schematically and includes a projection screen 10 , orchestra on stage 12 , audience seating area 14 , a conductor position 16 , a user/operator position 18 , a computer 20 , a projector 22 and a sound system 24 . The operator or user is seated with the musicians in the orchestra 12 so that he or she has a full view of the conductor, the projection screen 10 and the stage, and of course can hear any audio output of sound system 24 . Computer 20 is connected by wire or wirelessly to projector 22 and sound system 24 .
[0020] A rate control device 26 , shown schematically in FIG. 2 , is used by an operator to adjust the playback rate of a recorded video contained in the memory of computer 20 the video steam of which is communicated to projector 22 for projection onto screen 10 . The playback rate adjustment/user interface can be accomplished mechanically, as for example with a slider switch, roller ball, mouse or wireless motion mapping controller as seen in use in various video game and computer applications, and/or with a computing device having a touch screen on which various controls can be represented graphically and operated by touch contact therewith. Examples of suitable hardware for controller 26 include, but are not limited to, an Apple®, Windows® or Chrome® based tablet computer, a Windows®, Apple® or Linux® based notebook computer, an Apple® or Android® based smart phone, hardware controllers, such as; an Akai® APC40, Ableton® Push, Native Instruments® Maschine, or game controllers, such as used with gaming systems, including, for example, Xbox One®, Xbox 360®, Playstation 3®, Playstation 4®, Wii®, or WiiU®.
[0021] Rate Control Device 26 is connected wirelessly by Bluetooth®, or a suitable WiFi protocol or by wire, such as through a USB, Ethernet or firewire connection, to computer 20 . A specially designed application software 28 of the present invention is downloaded into computer 20 . The software 28 provides for responding to input from controller 26 as will be described in greater detail herein, to adjust the playback speed of a prerecorded video file. The time adjusted media signal is output from the software 28 to the projector 22 and sound system 24 .
[0022] FIG. 3 depicts the user interface of the software 28 as displayed on the screen of a controller. Each of the sections of this interface will be described in more detail below. In the upper left there is a video window 30 which displays video images exactly as they are output to the projector 22 . On the right is the Tempo Adjustment Window 32 which the operator uses to adjust the playback speed of the video file. The lower center section is the Visual Alignment Window 34 which acts like a visual metronome and is used by the operator to monitor the sync in real time. The lower left section is the Section Marker Tables area 36 , which contains tempo and time signature data that is manually entered prior to a performance.
[0023] The video window 30 provides a visual monitor of the images being outputted to the projector 22 . The video window 30 is driven by a movie player that is embedded into software 28 . The movie player is capable of playing movie files encoded in various formats such as .MP4, .MOV, .AVI and the like. The video player built in to the program is a software-based video player that plays only digital files. As is understood by those of skill, the video player is part of a built-in Standard Development Kit (SDK) as is available to any programmer in the programming language in which they are working. Inside the SDK are key elements intended to be used as “building blocks” for application development, one of which is a video player. The video player knows how to communicate with the video display hardware, read certain types of files, and distribute frames over time in a predictable way. Depending on the platform, the video player from the SDK may or may not have the ability to alter the time of a video. i.e., play it faster or slower. As is well understood this functionality can be added to the video player, or in the case of an SDK that allows for speed control, taken advantage of via code formatting to achieve the desired effect.
[0024] The tempo adjustment window 32 is shown in greater detail in FIG. 4 . This window is a display of the degree to which the operator is altering the speed of the video in the Video Window 30 . A vertically moving horizontal line called the tempo indicator 38 indicates the percentage that the video is being played faster, or in the case of a percentage less than 100%, slower. When this display shows the video is being played at a speed of 100%, as in FIG. 4 , the video is being presented unaltered—at its original speed. In other words, 100% playback rate=100% of normal or unaffected playback speed. Thus, 200% would be twice as fast as the original, and 50% would be half the speed of the original.
[0025] In the present invention the manipulation range is desirably set to allow the operator to adjust between 50% and 150% of the original tempo. Thus, one minute worth of video at 100% would take 45 seconds at 150%, that is, half again as fast. At 75%, that one minute would be played back at 75% of the speed, which would take one minute and 30 seconds, and at 50% or half speed that one minute would take 2 minutes. For reasons of practicality, the adjustment is typically limited to 150% of the original tempo, and 50% thereof. While adjustments with this system could happen beyond this scale, for most situations limiting to this range has the benefit of avoiding excessive pixilation and distortions in the video.
[0026] As seen in FIG. 5 , the visual alignment window 34 shows the current tempo after adjustments. The entirety of right-most box 34 a flashes, turns a solid color, at the moment the current beat or event occurs. This visually displayed tempo is the tempo of the digital media, not the tempo of the live performance. It is the job of the operator to match this visual tempo with what they hear of the live performance and make adjustments as necessary by using the tempo adjustment window 32 . For example, if this box flashes before the ‘live’ beat, it means they need to slow down the playback of the prerecorded media file until it matches, and flashing after indicates a need to speed up the playback of the prerecorded media file to match the live performance. The flashing of box 34 a is always calculated by the formula: [Original Tempo of current section]×[Current setting of Tempo Adjustment Window], the details of which are described herein below.
[0027] After the right-most box 34 a flashes, it shifts to the left by one division of the beat to box 34 b traveling left to right now as a non flashing vertical and narrower bar or line L thereby making room for the next division of the beat to flash in the right-most box 34 a. On the next division of the beat, the shift happens again, and so on until the left-most box 34 h receives the beat bar 8 divisions of the beat later. All rectangles in the grid 34 b - h are then in the past so to speak except for the right-most box 34 a, which indicates the current beat.
[0028] The tempo field tab 35 a displays the current tempo of the performance of the digital media. The number displayed in this box is not directly adjustable by the user. This number is constantly changing and updating in real-time to display the current tempo of the digital media as it is adjusted by the operator/user.
[0029] The particular section of the musical score can be numbered and that number displayed in Section tab 35 b.
[0030] The Bar and Beat identifiers tabs 35 c and 35 d report the current position of the prerecorded media/video based on previously entered data as described herein below. This display will align with the musical score to which the video was previously adapted and the user can use this display to ensure it is matched up with the live performance. The numbers displayed in these boxes are also not directly adjustable by the user during the performance but are visual informational readings of the time passing checked against the stated previously entered data. These numbers are constantly changing and updating in real-time to display the current position of the piece.
[0031] As seen in FIG. 6 , section marker table display area 36 includes a section table edit button 40 which is used to open a new window that shows a table editor display 41 , an example of which is seen in Table 1 below. Table 1 contains all the preparation data required to be entered before a performance of a prerecorded video file can take place. This information is created for each such media file to create a tempo map of the file that will identify the prerecorded video's exact position for each moment of performance in relation to the musical score of the live event. This data represents the unaffected tempo before the playback speed is modified by the tempo adjustment window 32 .
[0000]
TABLE 1
Frames Per
Section
Start Bar
Beat
Tempo
Signature 1
Signature 2
1
1
18
90
4
4
2
31
18
92
4
4
3
47
18
85
5
4
[0032] The “Section” column displays and contains the numerical ordering of sections within the digital video file. Each time a value changes in one of the other table columns it requires the creation of a new section.
[0033] The “Start Bar” column displays and contains the starting bar or measure for each section. This information is collected by the user from the musical score of the live event.
[0034] The “Frames Per Beat” column displays and contains information that is the result of the following mathematical calculation wherein: Frames per second (fps)×60=Frames per Minute (fpm), from which it follows that: Frames per Minute/Current Tempo=Frames per Beat (fpb). Thus, in an example where a film/video is rendered at 30 fps and the unaffected tempo of the event it is to be synced to is 120 beats per minute (bpm), we would calculate 30 (fps)×60=1800(fpm) and 1800(fpm)/120(bpm) =15, giving us 15 fpb.
[0035] The “Tempo” column displays and contains data that is the unaffected tempo of the music of the video file. This data and its entry and significance will be explained in greater detail below.
[0036] “Signature 1” column, using standard music notation practice, is the numerator or top number in time signature nomenclature and designates how many beats occur within each bar or measure of music for a given section thereof. This number is also entered into this column prior to the performance.
[0037] “Signature 2” column again, using standard music notation practices, is the denominator or bottom number in a given time signature and represents the type of note that equals one beat, e.g. where 4=a quarter note, 8=an eighth note, etc.
[0038] The data in Table 1 then describes the time and tempo parameters in the prerecorded digital video file that is to be synced to the live performance. Said another way, as the user manually enters these values a tempo map of the digital media is being created, which then can be used as a reference against the live event in performance as a further aid in mapping the video against the live event and showing places where the two may have fallen out of sync.
[0039] The mapping function is visually depicted on the user interface, FIG. 3 , by the visual alignment window 34 , which uses data from the Table Editor, seen for example in Table 1, to produce the visual metronome. Assuming the tempo indicator 38 is set at 100% and both the media file and live event begin simultaneously, the visual metronome in the visual alignment window 34 will match the tempo of the live performance until that time as the live event drifts from the “perfect” unaffected tempo entered into the Table Editor. Once this drift occurs the operator will see and hear the live performance go out of sync with the video by seeing that the flashing visual metronome in the visual alignment window 34 begins to flash out of time with what they are hearing with respect to the tempo of the live event. A simple correction by the operator by adjusting the tempo indicator 38 up or down will bring the video back into sync with the live event.
[0040] An overall view of the general flowchart of software 28 can be understood by reference to FIG. 7 . The process begins with the Table Editor window which contains data manually entered by a user prior to a performance. A media loader 42 is provided to load the video file to be synced into the software 28 . The user enters the data as per table 1 into software program 28 and a data loader 39 loads that data into software 28 . A synchronizer 44 collects data from the tempo adjustment window 32 , the section marker table 36 and the media loader 42 to calculate the data functions needed to achieve the sync. From synchronizer 44 output signals are delivered to video window 30 , projector 22 , sound system 24 and visual alignment window 34 .
[0041] A detailed flowchart of the synchronizer 44 processes can be understood by referring to FIG. 8 in combination with sample calculations relative to the data of Table 1 set out below.
[0042] For each section of the musical score, the number of beats per measure is taken from the “Signature 1” column. In the case of section 1 in the above example that number is 4. The tempo in the Tempo column, which in this example has been manually entered, calculates how long each beat should last. At a tempo of 90 beats per minute, each beat gets 667 Milliseconds. Thus it follows that, 60,000/[BPM]=Beats Per Millisecond, which is represented in box 50 of FIG. 8 . At a given frame rate of 18 frames per beat: 18 Frames =667 Milliseconds=1 beat. With this information, the frames per bar can be derived as: Frames per Bar, (box 52 ), is equal to [Frames per Beat]×[Signature 1] and thus producing Milliseconds per Bar, (as represented by box 54 ), which equals [Beats per Millisecond], (box 60 )×[Signature 1] resulting, in this example, as 72 Frames per bar, and 2,668 milliseconds per bar. The video then “knows” to run at the rate of 72 Frames per Bar, seen with respect to box 52 , from a start bar where: the Section Length, 46=[Section # at Start Bar]−[Section #+1 at Start Bar]. In our example then, Section 1 start bar=1, Section 2 start bar=31. Therefore, 1−31=30 (absolute value). Therefore, the video will run at the current frames per beat for 30 bars where: the Section Total, box 56 , =Milliseconds per bar, box 54 , ×Section Length, box 46 , which in the present example, would be 2,668 (milliseconds per bar)×30, which equals 80,040 milliseconds. Reduced for simplicity to 80.04 Seconds.
[0043] To locate each beat within a bar we calculate: Beats Elapsed, box 58 , =(Section Total), box 56 , /(Beats per Millisecond), box 60 , /(Signature 1). In this example then: 80,040/667=120/4=30 wherein the score should then be at the beginning of bar 30 . Any remainder from this last function is rounded to the nearest 0.25, then applied as:
[0044] (Beats Elapsed Remainder), box 62 , ×(Signature 2)+1=Beat Division, thus resulting in:
[0045] :00 (no remainder)=Beat 1
[0046] :25=Beat 2 of measure from Beat Elapsed), box 58 .
[0047] :50=Beat 3 of measure from Beat Elapsed, box 58 .
[0048] :75=Beat 4 of measure from Beat Elapsed, box 58 .
[0049] It is important to note that this calculation does not affect the playback speed of the digital media itself at all. This calculation only determines the “ideal” unaffected speed as the media progresses. The speed change is calculated based on these numbers multiplied by the manual tempo adjustment performed in the tempo adjustment window 32 .
[0050] In order to play at different speeds, software 28 simply needs to take the given frames per second of the selected file, and perform the following formula: New Frames Per Second=Frame Rate×Speed. Therefore, if the file is using 32 frames per second, which the program will quickly know from the file header information, then the computer can be told to play the file 32 frames for every second, when given the speed of 100%. Thus, 32=32×100%. However, when given another speed variable, the software can be told to distribute a different amount of frames over the same period of time, thereby slowing the video if the amount of frames per second is smaller than the initial frame rate, or speed up the video if the amount of frames per second is larger than the initial frame rate. For example, to play a video at exactly half the speed, the video player would be requested to play at 50%, which would only let in our example 16 frames elapse per second, i.e. 16=32×50%. If the video is to play at twice the speed intended, the command given would be 200%, that is, 64=32×200%.
[0051] It is important to note that this is continuous data, and the discrete data values shown are for visual reference only. Any value between 50% and 150% is possible, including any rational number within that range. For example, the operator could set the tempo to be 78%, 101%, 122.362%, etc.
[0052] The tempo indicator 38 is controlled by the operator as previously indicated by use of either a mechanical means such as a mouse, not shown, by clicking on and dragging tempo indicator 38 up or down, or virtually wherein controller has a touch screen that permits the operator to move tempo indicator 38 up or down by finger touch thereon. It can now be understood that the present invention allows for a level of sophistication in syncing video to a live performance that is not otherwise available. In most cases simply watching the video for visual cues about its position in relation to the live event is grossly inadequate. For example, a video showing a figure walking across the video's field of vision does not provide precise cues about how the video relates in time with the live event. To begin with, the pace of the walking may or may not be intended to be in time with the live event. Further, even if the walking projected in the video is designed to be in tempo with the live event, the operator has no way of knowing if the current step by the video character is aligned with the live event or if that step is one step ahead or behind its intended position in relation to the live event. By providing a visual representation of the ‘score’ of the live event the present invention allows for precision in keeping the video synced to a live event, both in terms of playback tempo and in terms of knowing exactly how far ahead or behind the video has fallen in relation to the live event.
[0053] Some further clarification about data values entered into the Table Editor (Table 1) is required. In current practice video files are edited using existing video editing software such as Final Cut Pro®, Adobe Premiere® or iMovie® to an existing sound recording of the source music to which the video is to be synced. This sound recording includes all of the unique tempo inaccuracies of that specific recorded performance. As a result, when the sound recording and the video are edited using such video editing software the edited video will also include allowances for all the same tempo imperfections as are found in the original sound recording. In live performance the tempo variation thereof will never match the recorded version, creating a type of distortion in the prerecorded video as compared with the current live performance.
[0054] For the most precise sync using the current invention, an ‘ideal’ version of the live event must be created that offers a tempo perfect version of the common musical score. The resultant musical score file will be mathematically perfect in terms of tempo. The video to be synced in live performance is first edited to sync with this tempo perfect sound file, essentially creating a prerecorded musical performance with absolutely no artistic expression in terms of tempo. This rhythmically sanitized version of the live event is used to create both the data entered into the Table Editor (Table 1) and the video file to be synced in a live setting.
[0055] Music notation software such as Finale® and Sibelius® can be employed to create the tempo perfect version of the live event. This ideal version is exported out of the notation software as an audio file, for example as a .wav or .aif file, and imported into the video editing software to be used as the soundtrack to the video. This “soundtrack” is for editing purposes only as the audio is never played in actual performance but only used as a framework to create the digital video file. | A method and apparatus are provided for producing full synchronization of a digital file with a live event. Using time-based cues such as musical beats, the live event is time mapped. The video file to be synced is measured in frames per second is then translated from its frames per second original time code into the time code of the live event in beats per minute making it possible to measure the playback rate of the source media file in the same units of measurement as the live event. The result is a playback mechanism that allows for more precise real time playback rate corrections by an operator by providing a visible cue so they can better keep the source media synced with the live event, even if there are real time tempo variations in the live event. | 7 |
FIELD OF THE INVENTION
The present invention relates to apparatus for selectably positioning livestock and to agricultural machinery generally.
BACKGROUND OF THE INVENTION
In the care of livestock such as cattle there arise a number of occasions wherein it is necessary to immobilize an animal to perform an operation thereon. This may include trimming of the hooves, branding, artificial insemination or various mechanical treatment. Normally, it is desirable that the animal be suspended in a lying position such that access is afforded to its abdomen and hooves. Hand-powered machinery is known for lifting livestock and positioning it in a tilted position. This conventional machinery has the drawback that it requires that a belt be secured under the animal for lifting thereof. Thus the operator must come into close contact with the underside of the animal. This involves a certain element of danger in that the animal may kick the operator and furthermore is strenuous, time consuming and unpleasant.
SUMMARY OF THE INVENTION
The present invention seeks to overcome the disadvantage of prior art apparatus and provides livestock positioning apparatus which does not require the fastening of a belt under the animal.
There is thus provided in accordance with an embodiment of the invention a livestock positioning device including a frame, apparatus for securing an animal within the frame without requiring operator contact with the animal and apparatus for orienting the frame so as to position the animal in a desired orientation.
The frame may comprise an outer frame which is selectably positionable, and an inner frame, raisably mounted within the outer frame and to which the animal is secured.
Power driven apparatus may be provided for orienting the inner and outer frames and for securing the animal to the frame.
In accordance with a preferred embodiment of the invention, the securing apparatus comprises a belt secured to the inner frame and located adjacent one side thereof when in a retracted position; and a power driven member associated with the belt for engaging the side underneath portion of the animal when the animal is located intermediate the belt and the opposite side of the inner frame, thus supporting the animal from underneath and causing the belt to engage the animal from the side, thereby to secure the animal within the inner frame.
The orienting apparatus may include apparatus for first raising the inner frame with respect to the outer frame and then for raising and tilting the frames in a desired sequence to a selectable orientation in which a desired portion of the animal is exposed.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will be more fully appreciated and understood from the following detailed description taken in conjunction with the drawings in which:
FIG. 1 shows positioning apparatus constructed and operative in accordance with an embodiment of the invention in a storage position on a mounting vehicle;
FIG. 2 shows the positioning apparatus of FIG. 1 at a position intermediate storage and stationary positions;
FIG. 3 shows the positioning apparatus of FIG. 1 in a stationary position and in engagement with an animal; and
FIG. 4 shows the positioning apparatus of FIG. 1 in a tilted position with the inner frame retracted.
DETAILED DESCRIPTION OF THE INVENTION
Referring now to FIGS. 1-4 there is seen in side view illustration positioning apparatus for livestock constructed and operative in accordance with an embodiment of the present invention. A tubular outer frame 10 is disposed on a mounting vehicle, such as a flat bed pick-up truck 12 which is formed to define a cam path 14 with associated support means 16. According to an alternative embodiment of the invention, the positioning apparatus may be mounted on any other suitable vehicle or may be mounted onto a fixed support. Support means 16 may be conventional retractable supports.
Tubular outer frame 10 defines first and second side portions 18 and 20 which are maintained in a desired spaced parallel orientation by top struts 22. The outer frame may conveniently be formed of heavy duty tubular stock, joined together by welding.
First second and third mounting lugs, 24, 26 and 28 are fixed to side portion 20 of outer frame 10 for attachment to power driving apparatus such as a hydraulic piston 30, mounted onto truck 12.
Supported onto outer frame 10 by a mounting structure 32 is a hydraulic cylinder 34, which in turn supports an inner frame 40. Inner frame 40 is typically formed of heavy duty tubular stock by welding or any other joining or forming technique, and defines first and second sides 42 and 44 and front and rear ends. Onto the front of outer frame 10, which is not illustrated in the drawings, there is hinged a conventional livestock neck securing gate and at the rear end there is hinged a gate of sheet metal stock 46. It is intended that an animal should enter the positioning apparatus through the rear gate and leave through the front gate. Animal leg securing grooves 47 are associated with the bottom portion of both gates.
Disposed adjacent the second side 44 of the inner frame 40 there is provided a support plate 48, typically formed of sheet metal. During operation of the apparatus, the animal is urged against support plate 48, and is supported thereby. Adjacent the first side of inner frame 40 there is mounted a hydraulic cylinder 50 having associated therewith a piston 52. Mounted onto piston 52 is an urging member 54. Urging member 54 defines a contact surface of curved, sheet like configuration and is arranged to engage the underneath side portion of an animal as illustrated in the drawings.
It is a particular feature of the invention that both the inner and outer frames are formed without bottom struts which could cause an animal to trip thereon or cause hesitancy of the animal to enter the frame.
A belt member 60 is freely suspended from the top portion of inner frame 40 and extends over the contact surface of the urging member 54 and is secured at its opposite end at a location 45 fixed to side 42 of the inner frame. The belt is arranged such that when the urging member 54 is in an extended position in engagement with an animal, the belt member 60 is drawn tightly about the side of the animal adjacent the first side 42 of the inner frame 40, thereby securing the animal against support plate 48.
It is noted that any of the power apparatus, such as the hydraulic cylinders hereinabove referred to may be alternatively of pneumatic, mechanical, electrical or any other suitable construction.
It will be appreciated that additional securing apparatus such as straps or chains (not shown) are associated with leg securing grooves 47 attached onto the front and rear gates.
The operation of the apparatus described hereinabove will now briefly by summarized:
It is assumed that the apparatus will be maintained in the storage position illustrated in FIG. 1 during transport from one site to another. Once located as desired, the frame means are lowered into an upstanding stationary position by attachment of driving cylinder 30 to mounting lug 26. Mounting lug 24 meanwhile travels along cam path 14. FIG. 2 illustrates the apparatus in an intermediate position while FIG. 3 illustrates the apparatus in a stationary position with the back gate open and the animal inserted therein.
The apparatus is prepared for entry of an animal by adjusting the inner frame to the animal height and fully retracting urging means 54 and associated belt member 60 so as to define a clear entry path. The animal then enters and is secured at the neck by the securing apparatus incorporated in the front gate. The rear gate is then closed. Hydraulic cylinder 50 is then operated to extend piston 52 and thereby bring urging member 54 into supporting contact with the side underneath portion of the animal, such that the animal is supported between support plate 48 and belt member 60. Cylinder 34 is then operated to raise the inner frame relative to the outer frame thereby to raise the animal's legs off the ground surface.
Hydraulic cylinder 30 is then attached to mounting lug 28 and is operated to retract associated piston 31 causing tilting of both the inner and outer frames as illustrated in FIG. 4. The frames may be tilted to any desired angle between the vertical and a horizontal disposition. Once a desired orientation has been reached, the animal's legs are secured to the securing grooves 47 associated with front and rear gates by suitable chains or straps.
Any desired operation, such as cutting of the hooves or medical treatment may then be carried out on the immobilized animal. The orientation of the animal may be varied before and during the operation by operation of cylinders 30 or 34. Upon completion of the operation, the frames are returned to a vertical orientation after release of the animal's legs, and the animal can exit from the apparatus through the front gate.
It is a particular feature of the invention that the securing, lifting and tilting of the animal are all accomplished without requiring the operator to actually contact the animal.
It will be appreciated by persons skilled in the art that although only a single preferred embodiment of the invention has been specifically described and illustrated herein, many other possible embodiments may also occur. The invention is expressly not limited to what has been specifically shown and described herein but rather is defined only by the claims which follow: | A device for positioning livestock including a frame, apparatus for securing an animal within the frame without requiring operator contact with the animal and apparatus for orienting the frame so as to orient the animal in a desired orientation. The frame may comprise an outer frame which is selectably positionable, and an inner frame, raisably mounted within the outer frame and to which the animal is secured. | 0 |
FIELD AND BACKGROUND OF INVENTION
[0001] The 802.11 standard is a family of specifications created by the Institute of Electrical and Electronics Engineers Inc. for wireless local area networks in the 2.4-gigahertz bandwidth space. 802.11 can be thought of as a way to connect computers and other gadgets to each other and to the Internet at very high speed without any cumbersome wiring—basically, a faster version of how a cordless phone links to its base station. With 802.11, electronic devices can talk to each other over distances of about 300 feet at 11 megabits a second, which is faster than some wired networks in corporate offices.
[0002] Devices using 802.11—increasingly known as Wi-Fi—are relatively inexpensive. A network hub, also known as an access point, can be bought inexpensively and will coordinate the communication of all 802.11 equipped devices within range and provide a link to the Internet and/or any intranet to which the access point is linked. The cards that let a laptop computer or other device “plug” into the network are also inexpensive. Some personal communication devices come enabled for 802.11 communications without the need of an additional card.
[0003] Providing so much wireless speed at a modest price is having profound implications for a world bent on anytime/anywhere communication. Wi-Fi is spreading rapidly. College students are setting up networks in their dorms and cafeterias. Folks in some parts of San Francisco are building 802.11 networks to cover their neighborhoods. Starbucks Corp., United Airlines Inc., and Holiday Inn, among others, are installing 802.11 networks in their shops, airport lounges, and hotels, in a nod toward their customers' desire to stay connected. It has been reported that, in 2000, the number of people using wireless local area networks rose by 150 percent, according to Synergy Research Group. Cahners In-Stat Group, a Scottsdale, Ariz.-based market research firm, sees the number of wireless data users in business growing from 6.6 million today to more than 39 million by 2006. Feeding this trend is the fact that almost a quarter of all workers in small or medium-sized business are mobile workers, spending at least 20 percent of their time away from the office. Wireless e-mail is their prime need, which is why mobile computing products with always-on e-mail capability continue to sell so well. In early 2002, it was estimated that between 25,000 and 50,000 people install and manage 802.11 networks every day.
[0004] Successor technologies to 802.11 are on the horizon. One is ultra-wide band radio technology or UWB, which uses a wide spectrum at low power to transfer data at a very high speed. UWB will be perhaps ten times faster than 802.11, yet suffer from some of the same needs described here. Another is the inclusion of radio frequency function directly on chips which perform other functions such as system central processors.
[0005] While the proliferation of 801.11 functionality has addressed issues of mobility with a geographically based network, there are issues left unaddressed. A geographically based network, as used in this description, is a data communications network formed by wired and wireless access points provided across and within a geographical area at fixed locations. A use of the data communications capabilities provided by the network may access those capabilities either by a wired connection at a fixed location or by establishing a wireless connection to a wireless access point which is at a fixed location. This mobility is enabled for users within the restraints imposed by the geographically based network. Within those restraints, a user may have mobility as allowed by the wireless capabilities of the user's system and the access points.
[0006] Such capabilities have not, however, extended to users who may be in transit. That is, a user going from one geographic area to another using transit services such as an autobus, airplane, train or the like will be out of communication during the necessary transit interval. This presents a disadvantage to some users. Further, where a group of business people are traveling together, the absence of connectivity during a transit interval detracts from possible useful group work.
SUMMARY OF THE INVENTION
[0007] With the foregoing in mind, it is a purpose of this invention to open communication during a transit interval as described above. In particular, the present invention contemplates that wireless connectivity be extended to users who are in public transport vehicles such as airliners, corporate aircraft, autobuses, trains and the like. Further, the present invention contemplates that the access allowed be extended to enable communications between such transiting users and between such transiting users and geographically based networks as described before.
[0008] In realizing these purposes, the present invention provides a wireless access point in a public transport vehicle and a data communication connection between that access point and more conventional geographically based networks.
BRIEF DESCRIPTION OF DRAWINGS
[0009] Some of the purposes of the invention having been stated, others will appear as the description proceeds, when taken in connection with the accompanying drawings, in which:
[0010] [0010]FIG. 1 is a schematic representation of a public transport vehicle in which the present invention is implemented;
[0011] [0011]FIG. 2 is a schematic representation of a flow chart illustrating the implementation of this invention.
DETAILED DESCRIPTION OF INVENTION
[0012] While the present invention will be described more fully hereinafter with reference to the accompanying drawings, in which a preferred embodiment of the present invention is shown, it is to be understood at the outset of the description which follows that persons of skill in the appropriate arts may modify the invention here described while still achieving the favorable results of the invention. Accordingly, the description which follows is to be understood as being a broad, teaching disclosure directed to persons of skill in the appropriate arts, and not as limiting upon the present invention.
[0013] Referring now more particularly to the accompanying drawings, FIG. 1 depicts a schematic view of the interior of a transport vehicle 10 for passengers, as indicated by the presence of a plurality of seats 11 for such passengers. The vehicle, in accordance with this invention, may be any vehicle for mass transport of people, such as an airplane, train, autobus, ferry or the like.
[0014] In order to enable communication through a network capable of linking passengers one to another and to network resources outside the vehicle, the vehicle is provided with a wireless data communications access point 12 . The access point 12 may be mounted within the vehicle 10 in any convenient manner and in any convenient location so long as the capability of linking passengers is maintained. As illustrated, the access point 12 is mounted in or adjacent the overhead or ceiling of the passenger compartment. The access point may be mounted in an convenient location from which effective communication may be maintained, and need not be visible to passengers.
[0015] The access point is coupled with a data link which is effective to couple the access point to a geographically based communications network; with a usage monitor which detects usage of data communication through the access point by a vehicle passenger; and with a usage fee calculator coupled to the monitor which calculates a fee to be charged to the vehicle passenger for usage of the access point. In FIG. 1, the data link, monitor and calculator are housed in a housing 14 which is adjacent to the access point and shown as outside the overhead. As will be understood by person of skill in the applicable arts of networking, the data link, monitor and calculator may be housed together or separately, within the access point or separately therefrom as shown, and in various other ways. What is significant is that a data communication link is provided from the moving vehicle to a data communications network which is more fixed in location. The monitor and calculator may be implemented through a conventional processor executing appropriate instructions to sense and record usage by passengers of the facilities provided by this invention. It is contemplated that passengers linking to the access point will be able to form ad hoc networks between or among passengers as well as communicate to the world outside the bounds of the vehicle through the data link. The service provider implementing the mobile access capability will be able to identify using passengers and charge for such usage in an appropriate manner based on data flow, bandwidth use, time, or other factors determined by the service providers business plan.
[0016] [0016]FIG. 2 illustrates, in flow chart form, the method of providing the service here described. The method has the steps of enabling data communication by providing a wireless data communications access point in a public transport vehicle; enabling data communication by providing a data communications path between the access point and a geographically based data communications network; monitoring communications exchanged through the access point; and charging fees based on communications usage to vehicle passengers communicating through the access point. The step of monitoring may include monitoring communications exchanged between or among passengers and between a passenger and the geographically based network to which the access point is linked. The public transport vehicle may be any transport vehicle capable of transporting passengers, including, but not limited to, an airplane, a boat or watercraft, a train, and a motorbus.
[0017] In the drawings and specifications there has been set forth a preferred embodiment of the invention and, although specific terms are used, the description thus given uses terminology in a generic and descriptive sense only and not for purposes of limitation. | Wireless connectivity for data communication is extended to users who are in public transport vehicles such as airliners, corporate aircraft, autobuses, trains and the like. The access allowed is extended to enable communications between such transiting users and between such transiting users and geographically based networks. | 7 |
BACKGROUND OF THE INVENTION
Technical Field of the Invention
The present invention relates in general to wheeled luggage, baggage, portfolios, briefcases, golf bags, and carry-on cases. In particular, to a removable wheel system that can easily be affixed to such articles and allow wheeled transport. More specifically, this invention relates to a frame structure and wheelbase with an attaching means.
Luggage is the broad term used to describe the variety of shapes and sizes of containers used to transport goods. The contents of the luggage also varies in size, shape, value, and fragility. The one common denominator is that carrying luggage is burdensome and difficult, especially when combining the weight of the luggage, cumbersome shape/design, and weighty contents.
In order to address the difficulties carrying luggage, wheeled luggage and multi-purpose carriers developed. Wheeled luggage refers to the various suitcases and baggage that employ wheeling devices, and allow users to roll their luggage. The wheeled luggage typically deploys a handle to aid in the transport and are usually hard cased units that have a plurality of wheels integrated into the design. The wheels are permanent features of the luggage and may or may not be fully retractable within the luggage.
Multi-purpose carriers are those devices that are used to aid in transportation of luggage, packages, groceries and other items. The multi-purpose carriers and carts are additional pieces of gear that must be available to the user. Luggage and other items are placed onto the carriers, which allow wheeled transport. Some of these carriers may be rented in some transportation terminals, or they may be personal carriers that are carried and stored in addition to the luggage.
Various attempts have been made to incorporate wheels into luggage and portfolio designs. A pair of retractable/extendible rear wheels is discussed in U.S. Pat. No. 5,758,752, wherein the rear wheels store inside a wheel bracket integrated into the luggage design and automatically deploy and retract by a spring assembly. In U.S. Pat. No. 5,813,503, a luggage case with a deployable handle has retractable/extendable wheel sets pivotably mounted to the luggage where a spring controls the extension and actuates when the handle is engaged. Another luggage wheel design is shown in U.S. Pat. No. 4,862,165, where the wheel assemblies are integrated flanges connected by a shaft that attach to the luggage and engage the wheel assemblies. A wheel housing member with integrated wheels is shown in U.S. Pat. No. 5,456,342, where the member is affixed to the luggage by rivets or screws and can incorporate a shield member. Another integrated design, U.S. Pat. No. 5,634,538 is a wheel assembly fitted into an engaging portion of the luggage and fixedly attached.
Luggage and baggage carriers are also disclosed in the prior art. The invention discussed in U.S. Pat. No. 4,506,897 is for a collapsible luggage carrier that has an integrated wheel assembly with wheel brackets hingedly attached to a U shaped frame. The wheels fold in on the carrier, allowing more convenient storage of the device. Another carrier is shown in U.S. Pat. No. 4,759,559, where the wheels are adjustable in height and connected to a Y shaped support structure.
U.S. Pat. No. 5,529,156 is a frame for soft-sided luggage. A lightweight and rigid frame with built in wheel wells and a shaft between the wheels can be integrated into the design of the soft-sided luggage.
There have been some attempts at implementing removable wheels. U.S. Pat. No. 3,861,703 uses hook and loop (more familiarly known as Velcro) to attach the wheels, wherein a flat mount bracket has one section of a hook and loop strip and the mating hook and loop strip is on the luggage. Support structures are attachable to the sides of the luggage and connect with a receiving portion on the flat mount bracket. Another detachable wheel patent in disclosed in U.S. Patent No. 5,188,381, where a bracket is connected or integrated onto the luggage, and the U shaped wheel and axle assemblies are attachable to the bracket.
While the wheeled suitcases and multi-purpose carriers are effective in some situations, certain types of luggage are not equipped with integrated wheels. And, there are certain instances where wheels are burdensome and inconvenient. As an example, cleaning soft-sided luggage with permanent wheels is much more difficult than washing such luggage without such structures.
Soft-sided luggage is popular for a variety of reasons, including being lightweight and foldable into a convenient size for storage. Traditional knapsacks are being re-designed to include permanent wheel assemblies. Students that have to carry heavy loads in their knapsacks can now wheel the load. The lightweight and portable soft-sided luggage is also preferred for the transportation of certain objects, particularly art. The soft-sided carrying units can be machine-washed and compactly stored when not in use. Pockets and storage compartments are easily implemented, and rigidity is provided by removable foamcore, corrugated plastic or cardboard inserts. Integrating wheels permanently into the design of the soft-sided luggage detracts from its advantages.
In addition, permanent integrated wheel assemblies have certain disadvantages. Wheel assemblies that are fully retractable within the case consume considerable cargo space of the luggage. Those assemblies that are not retractable protrude beyond the necessary shape of the luggage, requiring more space for carrying and storage. The wheel assemblies add weight and cost to the luggage as well as manufacturing difficulties.
Certain articles require specialized luggage, and conventional wheeled assemblies would not be possible. The shape of art portfolios is generally sized to transport works that are long and high, but narrow in width. A typical portfolio case is approximately four feet in length, three feet in height, and five inches in width. The carrying cases are designed to carry the general size and shape of art works, mostly prints (framed or unframed), that are transported in rectangular portfolios. The professionals using these bags require bags that are sturdy, lightweight, and aesthetically pleasing to transport the valuable contents. Once the works are inserted into the portfolios, they become very heavy, making the transportation onerous and more difficult.
Other types and configurations of art portfolios are common, including tube articles used to transport artwork that is rolled. These are cylindrical soft-sided canisters with a zippered top cover. The diameter varies in size, but are typically four, six, eight, ten and twelve inches. They are generally three to six feet in length.
Golf bags are also cylindrical shaped bags, typically soft-sided, that carry expensive and heavy clubs. Some bags employ permanent wheel assemblies affixed to the bottom, making carrying and storage more difficult. Without wheels, the user must carry the bag even when not on the golf course.
What is needed is a simple and easy-to-use removable wheel assembly. The assembly should be cost effective to manufacture and be made with long-lasting materials. The unit should install and uninstall quickly and not interfere with the usage of the luggage whether attached or unattached. This device should not detract from the aesthetic design of the luggage.
SUMMARY OF THE INVENTION
Accordingly, an object of the present invention is to provide a removable wheel system for luggage, baggage, carriers, golf bags, knapsacks, attaches, all-purpose sports bags, art tubes and portfolios. Once attached, the wheels allow the user to comfortably wheel the luggage to the desired destination.
Another object is to provide a luggage system with an easy attachment and removal of the wheel structure. The wheels can be removed and stored in the luggage or kept in storage.
An object of the invention, in one preferred embodiment, is a wheel system comprising a wing-shaped frame, an axle with wheels, and an axle-retaining portion. The axle-retaining portion has a loop portion that is secured to luggage by a fastening belt that is affixed to the luggage. Hook and loop straps work well in providing a quick and efficient fastening belt. The frame supports the weight of the luggage and keeps the wheels from contacting the luggage.
An object of the invention is a removable wheel assembly for luggage comprising a support frame with a pair of contacting lips. Each respective pair of contacting lips contact a bottom surface of the luggage and provide support for the article. The support frame has an angled mid-section connecting the contacting lips to a wheel base section. An axle is secured at the wheel base section, wherein the axle has a wheel attached to said axle. There is a pair of elongated members with securing slots extending from the wheel base section. Furthermore, there is a strap on each side of the luggage, each strap having a secured end and a free end, wherein the secured end is affixed to the luggage, and wherein the free end engages the securing slot of each of said pair of elongated members. There also is a means of securing the free end.
Another object of the invention is a removable wheel assembly wherein the means of securing the free end is selected from the group consisting of hook and loop, snaps, rivets, buckles, zippers and fasteners. The assembly can be secured by a cinch and fastener system, which is commonplace in the industry.
Yet another object is removable wheel assembly wherein the axle has a pair of wheels. Each of the wheels should be located either by the affixed securing strap or at a place that optimizes the transport of the article.
Further object is a removable wheel assembly wherein the pair of elongated members are bolted to wheel base section. The axle portion can thereby be retained and secured under the elongated members. An alternate embodiment is to weld or manufacture the elongated members to the wheel base, changing the assembly aspects slightly.
And another object is a removable wheel assembly wherein the pair of elongated members are adjustably slidably secured to the wheel base section, wherein a distance between the pair of elongated members is adjustable. The elongated members could be deployed within a track on the wheel base, thus allowing the dimensions between the members adjustable and allow different size luggage.
Additionally, an object is a removable wheel assembly wherein the wheel is rotatably swivel. Depending on the embodiment, a swivel wheel could be used in the invention and provide certain attributes, especially if only using one wheel.
Yet another object, is a removable wheel assembly, wherein a pair of removable wheel assemblies are secured to the luggage. Rather than just having one wheel on the axle, two wheels provide more support and ease of operation.
And, an object is a removable wheel assembly, wherein the strap secures the removable wheel assembly to the luggage without being affixed to the luggage, and wherein the strap engages each of the securing slots of the pair of elongated members and wraps around the luggage. In this manner the straps do not need to be sewn, glued or otherwise affixed to the luggage.
A further object includes a removable wheel assembly for cylindrical luggage comprising a housing with a pair of side flanges, a back portion with back flanges, and a wheel base section, wherein the pair of side flanges are angularly disposed from a wheel base section. There is a securing slot on one of the side flanges, and a securing strap for securing the assembly to the luggage, wherein the strap engages the securing slot of the housing. There is also a means of securing the securing strap to hold the unit to the luggage. An axle is affixed to the housing, wherein the axle has a first side and a second side, and wherein a first wheel attached to the first side of the axle, and a second wheel is attached to the second side of the axle.
Another object is a removable wheel assembly for luggage wherein the means of securing the securing strap is selected from the group consisting of hook and loop, snaps, rivets, buckles, zippers, cinches and fasteners.
Additional object includes a removable wheel assembly wherein the axle has a pair of wheels connecting to the axle.
Another object includes a removable wheel assembly, further comprising an axle strap, wherein the axle strap has a free end and a secured end, and wherein the secured end is affixed to the luggage, and the free end is threaded around the axle and fastened.
An object of the invention is a removable wheel assembly, wherein the securing strap has a free end and a secured end, said secured end is affixed to the luggage and the free end is threaded through the securing slot.
Yet another object is a removable wheel assembly, further comprising a securing slot on each of the side flanges, and a second securing strap, wherein each securing strap engages a securing slot. Furthermore, a removable wheel assembly, wherein the wheel is rotatably swivel.
An object of the invention is a removable wheel assembly kit for luggage, comprising a wheeled support frame with a securing slot, a strap for securing the support frame to the luggage, wherein the strap engages the securing slot and wraps around the luggage, and there is a means of securing the strap.
Another object is a kit, wherein the wheeled support frame has a pair of contacting lips, wherein each of the pair of contacting lips contact a bottom surface of the luggage, and wherein the support frame has an angled mid-section connecting the contacting lips to a wheel base section. An axle is secured at the wheel base section, and wherein the axle has a wheel attached to the axle. Furthermore, a pair of elongated members extend from the wheel base section each with the securing slot.
A further object is a kit, wherein the wheeled support frame has a housing with a pair of side flanges, a back portion with back flanges, and a wheel base section; an axle affixed to the housing, wherein said axle has a wheel attached; wherein the pair of side flanges are angularly disposed from a wheel base section, each with the securing slot.
And yet a final object is a kit wherein the means of securing the strap is selected from the group consisting of hook and loop, snaps, rivets, buckles, zippers, cinches and fasteners.
The luggage of the preferred embodiment is a soft-sided portfolio that is washable and stores compactly. A preferred embodiment is made out of 1000 denier Cordura nylon or similar materials. This material is durable, puncture proof, washable, and water-resistant. These articles include exterior pockets, interior straps, extra-wide gusset, removable shoulder strap, two side handle positions and a top handle. An extra-wide gusset of five inches allows larger materials to be placed in the portfolio. Other special features include double zipper construction for accessing materials easily, hook and loop straps to secure interior side panels to protect and separate materials. These cases are made in many different sizes.
Still other objects and advantages of the present invention will become readily apparent to those skilled in this art from the following detailed description, wherein only a preferred embodiment of the invention is described, simply by way of illustration of the best mode contemplated for carrying out the invention. As will be realized, the invention is capable of other and different embodiments, and its several details are capable of modifications in various obvious respects, all without departing from the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention will be readily understood by the following detailed description in conjunction with the accompanying drawings, wherein like reference numerals designate like structural elements, and in which:
FIG. 1 is a depiction of the article in transit.
FIG. 2 is a side perspective of the frame structure and wheel assembly.
FIG. 3 is an illustration of the separate components of the assembly.
FIG. 4 is a bottom perspective of the assembly.
FIG. 5 is a depiction of the cylindrical article in transit.
FIG. 6 is an illustration of the cylindrical article free-standing with assembly attached.
FIG. 7 is a front perspective of the assembly.
FIG. 8 is a side perspective of the wheel system for a tubular article showing the straps securing the article.
FIG. 9 is a top perspective of the wheel system for a tubular article showing the straps securing the article.
DESCRIPTION OF THE PREFERRED EMBODIMENT
In FIG. 1 a portfolio case 10 , typical in art transportation, has one removable wheel assembly 20 attached on a forward end, and a rearward removable wheel assembly 20 . A single wheel assembly is within the scope of the invention, especially for portfolios that are shorter in length. The wheel assemblies 20 are secured to the portfolio 10 by straps 30 that engage a securing slot on the support frame of the wheel assembly. The invention functions with other sizes and shapes of luggage, and the portfolio is merely a preferred embodiment for descriptive purposes.
The straps 30 are single length units approximately two inches in width and ten inches in length. There is a loose end of approximately five inches and a secured end of approximately five inches. The secured end is fixedly attached to the luggage and the loose end goes through the securing slot. In one variation, the straps are secured using hook and loop (Velcro being a trademark for one particular hook and loop device), wherein the gripping means is on the loose end and the receiving end is on the secured end. The gripping means is typically rows of small plastic hooking structures that adhere to the woven surface of the receiving end. Either the gripping end or the receiving end can be affixed to the portfolio. In the preferred embodiment, the receiving end is affixed to the sides of the portfolio. The straps 30 are affixed to the portfolio 10 by stitching or adhesive means. The placement of the straps is designed to optimize the weight displacement of the luggage.
Other securing means are within the scope of the invention, including buckles, buttons, ties, fasteners, and snaps. The wheel assembly of the preferred embodiment only requires a securing means engage the wheel assembly and provide a means for simple removal. There are multiple implementations possible to secure the wheel assembly to the luggage and provide easy attachment and removal. A single strap with securing means such as hook and loop can go around the luggage and secure the wheel assembly firmly in place. A cinch with fastening buckle is common in the industry and used in many devices intended for children. Thus, the invention can be in kit form and usable on any luggage within the dimensions of the invention.
On a portfolio 10 that is approximately 3.5 feet long and using two wheel assemblies 20 , the straps 30 are placed about eight inches from each respective end. The portfolio 10 would rest entirely on the wheel assemblies 20 . A portfolio 10 using a single wheel assembly 20 would place the straps 30 approximately twelve inches from either end of the portfolio 10 sides. In this situation, the portfolio 10 could employ only one pair of securing straps 30 and a single wheel assembly 20 , reducing manufacture costs. Two sets of straps would allow the user to place the wheel assembly on either set of straps. Using either method, the user wheels the portfolio and guides it by pushing, pulling or walking alongside.
A post can be used in place of a wheel assembly to allow the portfolio 10 to stand without support, while not interfering with the ease of rolling the portfolio 10 on the single wheel assembly 20 .
The use of temporary stiffeners, such as cardboard, foamcore, wood, or plastic, on the bottom and sides provide temporary rigidity to the luggage. The stiffeners can be inserted into specially designed pockets of the device. Other types and applications of stiffeners are well known, including a single piece stiffener that slips inside the portfolio. The wheel assemblies require some structural firmness on the bottom side, either from stiffeners, the contents of the portfolio, or a combination of the two. The invention is not limited to soft-sided luggage, and is equally amenable to the more conventional hard-cased luggage as well as other carrying cases such as golf club bags and knapsacks.
The workings of the wheel assembly 20 are detailed more precisely in FIG. 2 and FIG. 4 . The frame 50 is approximately wing-shaped, contacting the portfolio 10 at the contacting lips 70 on both sides of the wheel 100 . The contacting lips 70 are a small flattened region that engage the luggage. The middle portion of the frame 80 angles downward at an angle θ from the uppermost portion at some angle between 20 degrees and 60 degrees. The angle θ and the length of the middle portion 80 are established in order to keep the wheels 100 from touching the luggage 10 .
In one embodiment, the frame securing member 60 sits within a wheel base seating portion of the frame 90 . The wheel base portion 90 has notches 95 that provide better mating of the frame securing member 60 , especially if these are two separate components. The frame securing member 60 can be welded, riveted, bolted or otherwise secured onto the frame. An attachable frame securing member 60 permits the pre-assembly of the wheel assembly 20 .
The frame securing member 60 has a securing slot 35 that mates with the securing strap 30 . The strap 30 goes through the securing slot 35 and maintains the device in contact with the portfolio 10 .
It is well within the scope of the invention to employ a single manufactured structure 50 without a separate frame securing member 60 , thus eliminating the need for the notches 95 , and would likely reduce manufacturing and assembly costs.
An axle opening 65 in the frame permits the axle 110 to engage the locking washers 160 and wheels 100 and allows the wheeled transport. In a preferred embodiment, the wheels 100 have integrated bushing that allow the wheels 100 to spin freely without rotating the axle 110 . The wheels 100 are retained in position along the axle 110 by locking washers 160 . The axle 110 is secured to the frame 50 by press fit means or interference fit means if the frame 50 is a single manufactured unit. If the axle 110 is secured using a separate securing member 60 , it is attached to the wheel base section of the frame 50 by welding, riveting, screws, bolts, or adhesives. The axle 110 may or may not rotate during operation, but using wheels 100 with integrated bushings will not be effected by the axle rotation.
If the wheels 100 are to operate without bushings or bearings, the axle 110 will have to rotate in order for the wheels 100 to rotate. In this situation, a sleeve is used to encase the axle 110 and allow the axle 110 to freely rotate.
The support frame 50 can be manufactured from different metals and plastics, including acrylonitrile butadiene styrene (ABS), and polyethylene, high density (HDPE). The surface edges should be rounded to remove any burrs or sharp edges. Aesthetics are also important, and the color of the frame 50 is important to certain consumers. Although typically low gloss black, the frame 50 can be manufactured in a variety of colors or painted to match a particular luggage ensemble.
As shown in FIG. 3, one embodiment for manufacturing and assembling the support frame 50 is to use separate components comprising a wing-shaped frame member 75 , a securing member 60 , and the wheel 100 and axle 110 . The securing member 60 has a notched section 65 for the axle 110 , and which retains the axle 110 in a fixed position when the securing member 60 is affixed to the wing-shaped frame 75 . The securing member 60 is secured to the wheel base section 90 of the wing-shaped frame 75 by welding, riveting, screws, bolts, or adhesives.
An alternative embodiment for manufacturing and assembling is to make the securing member 60 an integral part of the support frame 50 . Assembly time would be decreased because the only installation would be the axle 110 , wheel 100 , and locking washers 160 .
A bottom view of the removable wheel assembly is shown in FIG. 4 . The width of the frame 50 , W, is designed to accommodate the width of the luggage 10 . In this preferred embodiment, the width of the support frame 50 is approximately six inches. It is within the scope of the invention to provide wider or narrower widths depending upon the width of the luggage 10 . It is also within the scope of the invention to employ an adjustable width support frame using extendable side securing members. The securing member from FIG. 3 can employ an extended securing section that mates with the wing shaped bracket. The securing member 60 is either pulled out or pushed in so that the width conforms to the particular luggage article. Once the width is set, a wing-nut or similar locking means secures the securing member 60 to the frame 75 .
The wheel 100 is kept in place within the open space 150 of the wheel chamber by locking washers 160 that are attached to the axle 110 on either side of the wheel 100 . The wheel assembly 20 can operate with a single wheel or a plurality of wheels, depending on the size and shape of the article 10 . In the preferred embodiment of a portfolio 10 , two wheels are utilized.
The length of the support frame, L, is approximately 7.5 inches from the outermost edges of the contacting lips 70 . The width of the contacting lips in the preferred embodiment is 0.75 inches. The angled middle section 80 is approximately 1.75 inches and the angular displacement θ is approximately 45 degrees. The length of the middle section and the angular displacement are designed so that the wheel does not scrape the luggage surface when rotating. The securing members 60 extends perpendicular from the axle and measure 1.75 inches from the axle 110 in the preferred embodiment. The wheels 100 are 1.625 inches in diameter. Larger wheels would require a different angle and/or a longer angled middle section 80 . The axle 110 is 0.25 inches in diameter, and uses locking washers 160 to retain the rotating wheel 100 in the proper position. As is obvious to one skilled in the art, the present invention is adaptable to many different articles by varying the individual elements.
FIG. 5 shows a variation of the present invention in the form of a removable wheel system for approximately tube-shaped luggage 200 . The tube wheel assembly 210 allows wheeled transport at an angle θ which is about 45 degrees. The handle 220 is on the top portion of the luggage 200 allowing the luggage 200 to be easily wheeled.
The tube wheel assembly 210 is designed so that the tube-shaped luggage 200 can stand vertically with no support as shown in FIG. 6 . The wheel assembly 210 is strapped to the luggage 200 by a single-piece strap 240 that goes from one securing slot 230 to a securing slot 230 on the other side. Using two independent straps 240 is within the scope of the embodiment, whereby each securing slot 230 has its own strap 240 .
The use of a single strap in conjunction with a single wheel assembly 210 allows the present invention to be sold as a kit. It can be used by any cylindrical or tube shaped luggage to allow wheeled transport, particularly golf bags. The orientation of the luggage 200 is important for proper rolling, and the wheel assembly 210 should be opposite the handle 220 .
An optional axle strap 250 provides further security and retention by wrapping around the axle 110 . Although not a necessity, this strap 250 gives an additional directional moment, pulling the wheel assembly 210 upwards into the luggage 200 in conjunction with the strap 240 pulling the assembly 210 sideways into the luggage 200 .
FIG. 7 is a front view of the tube wheel assembly 210 . The housing 300 is a three-sided enclosure with an open front for accepting the article to be transported. A securing slot 210 is incorporated onto one or more sides of the housing 200 . The wheels 100 connected are by an axle 110 , with locking washers 160 securing the wheels 100 on the outer end, and nylon spacers 310 on the inner end. The nylon spacers 310 maintain the wheels 100 in proper orientation along the axle 110 .
The housing 300 has a ‘Y’ shaped portion that allows for a wide variety of differing diameters to fit within the assembly. The lower portion of the housing 300 is angularly disposed from the ‘Y’ portion to allow the wheels 100 to operate properly.
FIG. 8 illustrates the tube assembly 210 in operation, wherein a side securing strap 240 goes through the side securing slot 210 and holds the article 200 to the housing 300 . This strap 240 pulls the tube perpendicular to the wheel frame. A single strap can accomplish this by going through the securing slots 210 and around the luggage, especially if the strap is tightly connected. Although flexible strap material is preferred, more rigid strap material provides less movement of the assembly 210 when secured.
The bottom strap 250 is used to interconnect the housing 300 to the cylindrical luggage article 200 . The bottom strap 250 wraps around the non-rotating axle 110 and is fastened by a securing means. The secured end of the strap can be affixed on the rear face of the luggage and travel along the tubular luggage 200 and thread around the axle 110 . This axle strap 250 serves a dual purpose. It is useful to prevent ‘kick-out’, where the luggage article 200 pulls away from the underside of housing 300 . Second, the bottom strap 250 orients the tube 200 in proper alignment for pulling from the handle 220 . If this handle is not oriented opposite of the wheel device, the luggage article 200 will tend to roll or lean to one side.
A top view of the tube assembly 210 in operation is shown in FIG. 9. A single securing strap 240 is used to secure the luggage to the assembly 210 . The strap 240 goes through a securing slot 210 of the housing 300 and adheres to itself using hook and loop. An optional bottom strap 250 wraps around the axle 110 and also secures to itself using hook and loop. The shape of the housing permits different size articles 200 because of the Y shaped design.
In operation, the wheel assemblies 20 , can be stored in one of the compartments of the portfolio until needed. To install the assembly 20 , place the luggage onto the assembly 20 so that the contacting lips 70 touch the bottom of the luggage. Detach the loose end of the hook and loop strap from the luggage 10 and feed the securing strap 30 through the securing slot 35 . Pull the strap 30 tight and secure the strap 30 . Repeat this for the opposing side of the wheel assembly 20 , and for all other assemblies 20 .
It is well within the scope of the invention to incorporate existing attachment mechanisms and employ manufacturing and molding techniques to incorporate and operate the present invention. The present invention has been particularly shown and described with respect to certain preferred embodiments of features. However, it should be readily apparent to those of ordinary skill in the art that various changes and modifications in form and details may be made without departing from the spirit and scope of the invention. Additional objects and advantages of the present invention may be further realized and attained by means of the instrumentalities and combinations all within the scope of the claims. The drawings and description are to be regarded as illustrative in nature, and not as restrictive. | A removable wheel system for luggage, baggage, portfolios, art tubes, knapsacks, golf bags, briefcases, and back packs. A frame structure with an integrated wheel base engages the article, and straps with attaching means secure the frame structure to the article. In one embodiment the frame structure has contacting lips upon which the luggage rests, while straps that are partly affixed to the luggage are threaded through securing slots of the frame structure and tightly secured. Cylindrical articles are carried by a frame structure with a Y shaped housing that secures the luggage to the frame by wrapping a strap around the luggage and engaging a securing slot on the frame. | 1 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates generally to photovoltaic cells and a method for making them. More specifically, it relates to improvements in stability and lifetime of these cells. Such cells are useful for converting solar energy into electricity.
2. Background
Stability and degradation problems have long plagued Cu x S/CdS solar cells. These problems are intimately related, in part, to the stoichiometry of the copper sulfide layer. Stoichiometry, which is a phase sum of mainly two dominant phases (chalcocite and djurleite), is important as optimum efficiency is considered to be obtained when the copper sulfide layer is predominantly chalcocite (Cu x S; 1.992<X<1.998) phase. Efficiency is degraded as the copper sulfide is oxidized to a higher oxidation state of copper, for example, to djurleite (Cu 1 .95 S) or digenite (Cu 1 .7 S). Several intrinsic mechanisms are thought to contribute to the degradation of the desired chalcocite phase to other phases causing the cells to gradually reduce their electrical output with time. Oxidation by external media as well as by copper migration through the layer via dislocation, stacking faults, subgrain boundaries and similar defects are thought to contribute to the chalcocite phase degreadation. Light and moisture are the dominant culprits in the chalcocite phase decay. Elevated temperature can enhance degradation.
U.S. Pat. No. 3,888,697 issued June 10, 1975 to Bogus et al obtains an improvement in stoichiometry of the cuprous sulfide layer by depositing on the copper sulfide layer an additional layer of copper metal. Presumably, the excess copper metal reduces any higher oxidation state copper present to produce chalcocite without altering defect-dominated chalcocite decay kinetics called the "memory effects" in Cu x S/CdS. The application of an additional chromium layer as provided by the instant invention provides prolonged chalcocite stability and a change in the built-in memory of Cu X S/CdS cells.
Japanese Pat. No. 4,824,675 issued July 23, 1973, to Hamaski purports to stabilize the properties of a solar cell by preventing oxidation of the copper ion by an electric current of excessive amperage, as may occur when the cell is in the short circuited condition or under heavy load, by adding a small quantity of metallic iron to the copper sulfide. Presumably, the metallic iron acts similar to metallic copper in being oxidized in preference to the cuprous sulfide.
Metallization of the copper sulfide layer by chromium of the instant invention has a three-fold purpose,
(1) Chalcocite phase stabilization in the copper sulfide layer
(2) Throttlement of defect induced copper electromigration, and
(3) Formation of a coherent, passive oxide Cr 2 O 3 layer which protects relatively unstable chalcocite from ambient.
SUMMARY OF THE INVENTION
This invention essentially comprises a cadmium sulfide-copper sulfide photovoltaic cell having improved stability. This improvement in stability is obtained by depositing a film of chromium or various combinations of chromium with copper over the copper sulfide. The chromium layer stabilizes the chalcocite phase of the copper sulfide, providing sustained high efficiencies under prolonged light and moisture exposure; it reduces copper electromigration which reduces cell degradation under high current loading conditions, and also provides physical protection to the cell against the external environment. Thus, the application of a layer of chromium provides several improvements over the prior art: (i) chalcocite phase stabilization probably by elimination of any soft phonon modes; (ii) throttlement of copper electrotransport via defect paths by reducing the effectiveness of these paths by pinning them and inhibiting their multiplications; and (iii) instantaneous formation of a thin passive and coherent oxide layer (Cr 2 O 3 ) (not the case for either copper or iron oxide), which being a poor vacancy source will reduce the localization of point defects near the surface and thus reduce lateral copper electrotransport, in addition to the protection of the relatively unstable chalcocite from ambient.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a cross-sectional view of a photovoltaic cell of the invention. This cross-sectional view is not to scale since it would not be practical to show in a drawing the true thickness of the various elements of the cell.
FIG. 2 shows various embodiments of the chromium layer 15 of FIG. 1.
FIG. 3 shows various processing flow diagrams for chromium (or copper-chromium) metallization of the p-layer and heat treatments.
FIG. 4 shows preferred orientation indicating dominant Bragg reflections of the copper sulfide layer on C-axis oriented cadmium sulfide for the p-layer having 100 percent (a) chalcocite, (b) djurleite and (c) digenite, respectively.
FIG. 5 shows the time dependence of the chalcocite phase decay in the p-layer in Cu x S/CdS heterostructure and the effects of chromium metallization of Cu x S in throttling the decay.
FIG. 6 shows the effects of heat treatments, copper treatments and chromium metallization of the p-layer (d) with various initial stoichiometries (a, b and c) on chalcocite decay kinetics (e and f) describing the "memory" of the Cu x S/CdS system and its elimination by chromium metallization.
FIG. 7 shows concentration profiles of various elements in cadmium sulfide/copper sulfide/chromium layer.
FIG. 8 shows the formation of djurleite in the p-layer at the expense of chalcocite decay as a function of exposure of light in air at 60° C. The formation of djurleite phase correlates positively with cell degradation.
FIG. 9 shows the chalcocite phase decay as a function of exposure of light in nitrogen atmosphere at 60° C., indicating the throttlement of chalcocite decay by chromium metallization of Cu x S.
FIG. 10 shows a histogram of the distribution of short circuit current loss rate in nonmetallized Cu x S/CdS solar cells in Phoenix sunlight (DSET Laboratories) under short circuit or 0.3 V loading, indicating an average loss of 0.187% in SCC loss/day; comparatively x, chromium (with or without copper)/copper sulfide/cadmium sulfide materials show an average loss of 0.04% in SCC loss/day.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The use of a cadmium sulfide-copper sulfide photovoltaic cell is well known in the art. This type of cell is used, for example, as a solar cell. Since each cell generates only a small amount of power, usually much less power than is required for most applications, the desired voltage and current is realized by interconnecting a plurality of solar cells in a series and/or parallel matrix. This matrix is generally referred to as a solar cell array. As used herein the term "photovoltaic cell" includes within its definition such arrays of cells as well as the individual cells. Illustrative of such arrays are U.S. Pat. No. 3,483,038 issued Dec. 9, 1969, U.S. Pat. No. 3,571,915, issued Mar. 23, 1971 and U.S. Pat. No. 4,127,424, issued Nov. 28, 1978, incorporated by reference herein.
The photovoltaic cells of the instant invention and the method of making them are conventional and described in the art except for applicant's improvement of applying a chromium film to the copper sulfide layer prior to adding a collecting electrode. Typical of such prior art cells is that of Carlson et al, U.S. Pat. No. 2,820,841, issued Jan. 21, 1958, (incorporated herein by reference) one of the earliest patented cadmium sulfide-copper sulfide cells. The cell is further illustrated in FIG. 1. Layer (11) is typically a supportive substrate made of, for example, glass, ceramic, metal, or plastic. For purposes of illustration, a non-conductive substrate is shown to which is attached conductor electrode (12), cadmium sulfide layer (13) and copper sulfide layer (14). Next is applicant's improvement comprising a chromium-containing layer (15), followed by a collector electrode (16).
The photovoltaic cell may be either a front-wall cell, a backwall cell or a combination of both. In a front-wall cell, light enters the absorber, which in this case is the cuprous sulfide layer. For this type of cell the collector electrode must allow light to pass through it and is usually a grid of electrically conductive metal such as gold or copper. Therefore, the chromium layer convering the cuprous sulfide must be thin enough not to absorb excessive amounts of light. For a front-wall cell, the conductor electrode attached to the cadmium sulfide layer and the substrate is not required to be transparent. Illustrative of front-wall cells is U.S. Pat. No. 4,127,424, issued Nov. 28, 1978, incorporated by reference.
For a back-wall cell the substrate and the conductor electrode attached to the cadmium sulfide layer must be transparent, as the cadmium sulfide layer is exposed to the light. Thus, the chromium layer and the electrode for the cuprous sulfide need not be transparent. Typically, the substrate for back-wall cell is transparent glass or plastic and the electrode for the cadmium sulfide layer is conductive tin oxide, indium oxide or mixtures thereof. Illustrative of a back-wall cell is U.S. Pat. No. 4,143,235, issued Mar. 6, 1979, incorporated by reference herein.
The cell may also be a combination of a front-wall and a back-wall cell as illustrated by U.S. Pat. No. 3,376,163 issued Apr. 2, 1968, incorporated by reference. In this case, the substrate, chromium layer, and both electrodes must be transparent.
The key aspect of the instant invention is the application of a chromium-containing layer to the copper sulfide. This is denoted as layer 15 in FIG. 1. This chromium-comprising layer (15) is applied as the metal in any conventional fashion such as by evaporation, sputtering, ion-plantation, etc, electrolytically, or chemically as by electroless plating. Because of the thinness of the chromium-comprising layer and the strong oxygen-gettering ability of chromium, the chromium will be present in the chromium-comprising layer as primarily the oxide (Cr 2 O 3 ), having been converted to the oxide during either the application process or, desirably, the oxidation is affected later by heating in air. The remaining chromium segregates preferentially around energetically favorable defect sites, preventing their multiplication and propagation.
FIG. 2 illustrates various embodiments of the chromium comprising layer. Layer (15a) represents the application of primarily a chromium-comprising layer. Layer (15b) represents first the application of a copper layer as exemplified by U.S. Pat. No. 3,888,697 issued June 10, 1975 to Bogus et al, incorporated by reference, followed by the application of the chromium-comprising layer. Layer (15a) reverses the process of layer (15b). The copper is applied in any conventional fashion; evaporation, chemical, electrolytic. Layer (15d) illustrates the simultaneous application of chromium and copper, producing an intimate mixture thereof. The chromium-comprising layer will typically range from about 8 to about 15 angstroms for front-wall cells and from about 10 to about 25 angstroms for back-wall cells. For the composite layer, copper on chromium or chromium on copper, the chromium layer will range between about 8 and about 15 angstroms and the copper layer will range from about 50 to about 100 angstroms for a front wall cell. For the back-wall cell the chromium will range from about 10 to about 25 angstroms with ano critical limit on the copper although it will typically range from about 50 to about 100 angstroms. For the layer comprising a mixture of copper and chromium, the layer will range in thickness from about 50 to about 100 angstroms for front-wall cells and from about 75 to about 100 angstroms for a back-wall cell. There are two basic limitations on the thickness of the chromium-comprising layer. First, when light must pass through this layer, it must be thin enough not to absorb excessive amounts of light, particularly on the shorter wave lengths (blue region) where it is found to have a higher absorption coeffecient. Secondly, the chromium-comprising layer should not be so thick as to provide excessive electrical resistance between the copper sulfide layer and the collector electrodes.
A preparation of a photovoltaic cell illustrative of the instant invention is described below: other variations will be apparent to one skilled in the art.
The first step in forming a cell having a non-conductive substrate is to coat the substrate 11 (see FIG. I) with a conductive layer to form the conductor electrode 12. Typical substrates include plastics, or ceramics. Various substrates are disclosed in U.S. Pat. No. 3,483,038; U.S. Pat. No. 3,376,163; and in U.S. Pat. No. 4,127,424 noted above. The conductor electrode or conductive layer typically comprises a conductive metal such as zinc or silver or a conductive ceramic as described in U.S. Pat. No. 4,127,424 noted above. More than one layer of metal may be deposited on the substrate if desired (e.g. Cu-Zn, or brass). In some cases a metal substrate may be used which also serves as the conductor electrode, e.g. a molybdenum substrate may serve as the electrode. In addition, a thin film of an electrically conductive metal such as zinc may be applied to the electrode to provide ohmic contact.
Upon this conductor electrode a semiconductor material such as cadmium sulfide film 13 is deposited. This can be done in a known manner, such as through a suitably apertured mask from the vapor state. The thickness of the layer may be about 20 microns to about 100 microns, as disclosed in U.S. Pat. No. 3,186,874, issued June 1, 1965, incorporated herein by reference. The cadmium sulfide film 13 typically covers and completely overlaps all but a small portion of the bottom electrode. The uncovered portion can be used subsequently either for electrical connecting means to an adjacent cell, such as the top electrode of an adjacent cell to make a series connection therewith, or for a negative output terminal. When the substrate is insulating, as shown, the cadmium sulfide film 13 in each of the cells typically overlaps the remaining periphery of the conductor electrode and extends to the surface of substrate 11 in order that the subsequent overlapping films and the collector electrode in each cell do not contact the bottom electrode layer 12.
The surface of the cadmium sulfide film 13 may be etched with hydrochloric acid for about 4-5 seconds, if desired, before the cuprous sulfide film is formed therein, as described in U.S. Pat. No. 3,480,473 issued Nov. 25, 1969, incorporated by reference herein. The cuprous sulfide film 16 is formed in a suitable fashion such as, for example, deposition from the vapor state through a suitably apertured mask over the cadmium sulfide film 13, or by contacting the cadmium sulfide film 13 with an aqueous solution of a cuprous salt as, for example, a cuprous chloride or bromide or iodide solution, as described in Keramidas, U.S. Pat. No. 3,374,108 issued March 19, 1968, incorporated by reference herein. The cuprous sulfide film 24 may have a thickness between about 1000 A and about 10,000 A.
Following the depositions of cadmium sulfide and copper sulfide layers, the cell is subjected to a heat treatment usually at a temperature of from about 100° C. to about 300° C., which activates the p-n junction. The heat treatment may be provided right after deposition of the copper sulfide, in which case the heat treatment must be carried out in vacuum, but more conveniently it is carried out after deposition of the chromium layer or after the cell has been gridded or encapsulated, in which case it may be carried out in air as well as in vacuum. Combinations of the above may be used. (See FIG. 3 for process flow diagram.)
After the copper sulfide film is produced, the chromium comprising layer is added in a traditional fashion; vacuum evaporation, chemically or electrolytically. Vacuum deposition is preferred. Vacuum deposition systems are readily available commercially to carry this step. When copper is also deposited, it is also done conventionally, i.e., vacuum deposition, chemically or electrolytically. Vacuum or electrolytic deposition is preferred for copper.
After the chromium layer is added, a collector electrode is affixed. The collector electrode can suitably be any materal of high electrical conductivity. Suitable materials are, for exemple, gold, platinum and copper. For front-walled cells, it must allow or be shaped to allow passage of light. Such electrodes are known in the art. The collector electrode may be provided in any manner such as by deposition through a suitbly apertured mask from the vapor state. Alternatively, the top electrode may be vapor deposited or screened onto a flexible insulating film such as Mylar, Aclar or TFE and then the film pressed into the cell with the collector electrode in ohmic contact with the chromium-comprising layer and held in place with a light transmissive adhesive. The collector electrode can also be a grid, or mesh, of fine metal wire.
The finished cell assembly is then usually sealed or encapsulated with a protective light transmitting coating or a protective film or plate of a material such as glass, plastic or the like. The protective film should be impervious to oxyen and water vapor which would degrade the cell.
Two typical schematic flow diagrams for the preparation of cells using the chromium metallization of the instant invention are shown in FIG. 3. Process 1 shows the laying down of the n-layer on the substrate, followed by the p-layer and then the chromium-containing layer. This is followed by a series of heat treatments in air, vacuum and then air, followed by the gridding, lamination and packaging. Process 2 differs from 1 in that after barriering, the cell is vacuum heat treated, then chromium metallized and then air heat treated, followed by gridding, lamination and packaging. Analysis by optical transmission and chemical analysis showed the chromium-layer to range from about 50-100 A in all metallizing treatments.
The preparation of the cells of this invention and the improvement accruing therefrom are illustrated by the following illustrative embodiments which are provided for illustration and are not to be construed as limiting this invention.
Illustrative Embodiment
(i) X-Ray Diffraction Analyses of Various Phases of Cu x S on C-axis Oriented CdS
FIG. 4 shows the Bragg scans of the p-layer on the Cu x S/CdS heterostructure. FIG. 4(a) indicates when the Cu x S layer is ˜100% chalcocite. Preferred orientation of the p-layer on the oriented CdS is self-explanatory. Most of the dominant reflections are on the low angle side (25°<2θ<42°). Absence of other reflections as observed in bulk chalcocite is due either or preferred orientation and/or buried under strong CdS peaks. FIG. 4(b) shows an XRD scan of the p-layer when the system is ˜100% djurelite on oriented CdS. (This is equivalent to x=1.93.) Again, the dominant reflections are on the low angle side (30°<2θ<45°). Miller indices were evaluated using both orthohombic and monoclinic indexing for chalcocite and djurleite. The p-layer in the Cu x S/CdS system was completely converted to digenite (x˜1.75) by exposing the nude cells to a high humidity atomsphere for over 40 hours or submerging them in H 2 O at room temperature for a few hours. Relevant Bragg reflections of digenite on oriented CdS are shown in FIG. 4(c).
(ii) Chalcocite Decay Kinetics--Memory Effects in Cu x S/CdS Heterostructure
Chalcocite→djurleite phase transformation occurs by the process of nucleation and growth on energetically favorable sites obeying the kinetic law:
f.sub.d.sbsb.j =1- exp [-K(ρ.sub.⊥, T)t.sup.n ] (1)
where f d .sbsb.j is the fraction of transformed djurleite in the chalcocite matrix in time "t".
f.sub.d.sbsb.j +f.sub.ch =1 (2)
K(ρ.sub.⊥, T)--effective time independent rate constant (defect density and temperature dependent)
n--experimentally determined reaction mechanism dependent constant
f ch (t)--can be defined in terms of integrated intensities of (106) Bragg reflection with respect to t o as: ##EQU1## and similar equations exist for "f d .sbsb.j ". Using 1 and 2, one can obtain:
log log (1/f.sub.ch)=n log t+ log K (3)
Initial decay kinetics indicate n˜0.5-0.95 and - log K˜2-5 in Cu x S/CdS heterostructure. The effects of chromium metallization of Cu x S in suppressing chalcocite decay are indicated in FIG. 5. The built in memory in Cu x S/CdS, which governs the chalcocite decay kinetics, constitutes
(i) initial defect concentration in CdS (substrate and/or thermally induced),
(ii) defect generations for lattice accommodation during topotaxy, and
(iii) state of stress and stress-induced defect multiplications.
FIG. 6 (a, b and c) shows Cu x S/CdS with varying degrees of initial djurleite concentrations and chalcocite decay rates (e) are converted to 100% chalcocite (d) after a conventional vacuum heat treatments (VHT) and/or copper (Bogus) treatment retained their "memories" whereas chromium (with or without copper) changes dramatically the chalcocite decay kinetics and "memory" in the Cu x S/CdS heterostructure (FIG. 6(f)).
(iii) Effects of P-layer Metallization on Substructural and Lattice Properties of the Cadmium Sulfide
X-ray crystallite size, microstrain distribution and defect analyses (faults and dislocations) were ascertained from Fourier deconvolution of Bragg profiles for both basel and nonbasal reflections using thermally recrystallized CdS as a standard. Accurate lattice parameters "c" and "a" were obtained from the peak positions of basal and nonbasal reflections after various stages of processing, including Cr or Cu:Cr metallization of the p-layer.
Lattice Properties
(a) There are contractions in both "c" and "a" without altering the c/a ratio after every stage of processing with major changes occurring during etching and barriering (E & B) towards the recrystallized (CdS) value.
(b) CdS basal peak shift occurs towards the higher Bragg angles after E-B, indicative of the state compression of the basal planes. Cu x S/CdS with relatively good memory shows a smaller basal peak shift than that of the system with a bad memory.
(c) The lattice parameter "c" gets drastically reduced by chromium (with or without copper) metallization of Cu x S without significantly affecting "a", thus reducing the "c/a" ratio substantially towards the ideal value of 1.61872 (recrystallized CdS or (002)--oriented single crystal value).
(d) The "memory effects" have no substantial influence on the absolute values of c and a; however, the c/a ratio for a system with good memory is closer to the "c/a" ratio of a recrystallized CdS than that of a system with bad memory.
__________________________________________________________________________Effects of ProcessingStructural/Substructural CdS After 6 Secs. Etch CdS After E & B Cu:Cr-Cu.sub.x S/CaS AfterParameters* CdS As Deposited & 20 Secs. Barrier VHT (175° C., 20 Heat Treatment__________________________________________________________________________"c" in A 6.72333 6.71909 6.71886 6.71859"a" in A 4.13739 4.13267 4.12815 4.13796"D.sub.av. " in A 1487 919 984 475(Basal Crystallite Size)RMS strain × 10.sup.-4 8.619 9.932 8.581 8.718<ε.sup.2 >.sub.004.sup.1/2, L = 100 AAv. Strain × 10.sup.-4 1.764 2.596 2.815 8.62<ε>.sub.004, L = 100 AD.sub.eff [(105), (107)] 225 227 240 210(Nonbasal Crystallite Size)D.sub.eff [(106), (108)] 162 160 170 140(Nonbasal Crystallite Size)α(× 10.sup.-3) 6.9 5.8 7.5 5.95(Deformation StackingFault Probabilities)β(× 10.sup.-3) 5.9 6.4 6.3 1.23(Growth Stacking FaultProbabilities)ρ (cm · cm.sup.-3) (004), 2.555 × 10.sup.11 4.769 × 10.sup.11 3.852 × 10.sup.11 8.088 × 10.sup.11⊥ L = 100 A(Basal Dislocation Densities)__________________________________________________________________________ *Memory = 40% Djur. After 7 Days.
(e) The basal crystallite size "D" av . and ##EQU2## (rms strain) get continually reduced during etching, barriering and heat treatments with major changes occurring during the etching and barriering operation. The nonbasal, fault-affected crystallite size, faulting probabilities and energies do not change significantly after every stage of processing.
(f) P-layer metallization by chromium (with or without copper) causes a small increase in basal average strain dislocation densities and a reduction in basal crystallite size and stacking fault probabilities.
(iv) Nature of Metallized Chromium Comprising Layer
Metallized (Cr, Cu:Cr and Cr:Cu) Cu x S and controls were depth profiled from the top layer to 2000 A deep by Ion Scattering Spectroscopy/Secondary Ion Mass Spectroscopy (ISS/SIMS). These samples were prepared according to Process 1. Cr or Cu:Cr were metallized after barrier formation, given a 175° C. heat treatment in air for 8 minutes, a vacuum heat treatment for 20 hours at 195° C., followed by an air heat treatment for 1 hour at 125° C. Concentration profiles of Cu, S, Cd, O and Cr were made by ion-milling the surface every 10 A layer for the first 200 A, followed by milling every 100 A layer and analyzing the secondary ion yield spectra of the above species up to a depth of 2000 A from the surface (external surface of the chromium-containing layer). FIG. 7 shows the depth profiles up to 1200 A depth only. These results are summarized below:
(a) Control: there is no apparent oxide layer (Cu 2 O?) beyond the 20 A depth from the Cu x S surface. The oxygen ion yield from the top 10 A layer could be from surface contaminants or Cu 2 O and within the resolution of the instrument; however, this layer cannot be quantified other than the fact that the incoherent Cu 2 O layer is not thicker than 10 A. Up to 75 A, the Cu:S ion yield ratio is a little less than 2 and beyond the Cu:S ion yield maintains a constant ratio of 2 all the way up to 1200 A. The interface based on the Cu and Cd concentration profile crossing occurs at 615 A; the junction, however, extends beyond 2000 A. The Cd ion yield monatomically decreases across the interface and reaches a minimum at 150 A, followed by a finite increase near the surface in all cases.
______________________________________(b) Cu:Cr (c) Cr:Cu (d) Cr______________________________________Oxide layer 240 A Oxide layer 170 A Oxide Layer 650 A(mainly Cr.sub.2 O.sub.3) (mainly Cr.sub.2 O.sub.3) (mainly Cr.sub.2 O.sub.3)Cu:S (ion yield ratio) Cu:S 1 at 50 A Cu:S at 50 A and1 at 50 A depth and and reaches reaches a peak of 2reaches a peak of 2 at a peak of 2 around 750 A where450 A, maintaining the Cu.sub.x S/Cds interfaceratio of 2 all the startsway up to 1200 A depthInterface starts Interface starts Interface startsaround 750 A around 650 A around 750 A______________________________________
Both for Cr- and Cu:Cr doped Cu x S, their concentration profiles for O and Cr are parallel with respect to each other up to their corresponding oxide layer thickness. This was not the case on Cr:Cu doped Cu x S, which could be atributed to the way the p-layer was metallized (Cr metallization first, then the vacuum is broken thus forming an instantaneous passive Cr 2 O 3 layer followed by Cu metallization on top of it). In any event, a finite amount of Cr tail does exist in all three cases, although the chromium exists in the cell as primarily Cr 2 O 3 . The Cr tails segregate preferentially around defect sites and pin them, thus preventing their multiplication and propagation.
(v) Light Induced Chalcocite Decay in Air
A series of cells were prepared according to the teachings of U.S. Pat. No. 4,127,424. After evaporation of the cadmium sulfide and formation of the copper sulfide barrier layer, the cell was given a vacuum heat treatment at 195° C. for 16 hours, and a heat shot at 175° C. in air for 15 minutes. Then a layer of chromium, a layer of copper or a layer of copper followed by a layer of chromium was vacuum (4×10 -6 torr) evaporated onto the cell. After this "metallization" the cell was heated in air for 1 hour at 175° C. The cells were then subjected to a test for chalcocite phase stability by subjecting them to a continuous exposure of light (100 mW/cm 2 ) at 60° C. in air. The cells were analyzed by x-ray diffraction to determine the degradation of chalcocite into djurleite by analysis of the relative intensities djurleite [(1.1.11) and (1.0.11)] and chalcocite (1.0.6) Bragg peaks. Results are shown in FIG. 8, which shows the relative intensity of the djurleite peak as a function of light exposure.
Light Induced Chalcocite Decay in Inert Atmosphere
Halves of Cu:Cu x S/CdS, Cr:Cu x S/CdS and their equivalent Cu x S/CdS controls (prepared by Processes 1 or 2) were subjected to continuous exposure to light (100 mW/cm 2 ); the other halves were kept in the dark for 6 weeks at 60° C. under continuous N 2 -purging. The second experiment yields the chalcocite decay by light alone compared to the first experiment which combines the effects of light and oxygen. Chalcocite decay based on relative decay of chalcocite (106) with respect to djurleite [(1.1.11) and (1.0.11)] Bragg reflections are shown in FIG. 9. The beauty of Cr-doped Cu x S compared to control or Bogus-treated Cu x S in throttling chalcocite decay is self-explanatory.
Observations
1. There is a definite light-induced chalcocite decay when the doped halves in light are compared with other doped halves in the dark. The rate of chalcocite decay is fastest for Cu:Cu x S/CdS or Cu x S/CdS system irrespective of the metallizing/VHT sequence (Process 1 or 2).
2. Metallizing→VHT sequence is better than that of VHT→metallizing (Process 2) sequence in terms of the rate of djurleite rise, which was also confirmed by lifetest data.
3. Cu:Cr-Cu x S (light) always shows a Cu (111) Bragg peak near the chalcocite (106) indicating a lot of Cu electrotransport near this open-circuit condition (this "Cu" cannot be detected by optical microscope)--which was not detected in either Cu:Cu x S or Cr:Cu x S (light) samples.
4. Initial djurleite rise curve for Cr or Cu:Cr doped Cu x S is fastest for the first week of testing (still much lower than control or Cu:Cu x S), then the rate of the phase degradation becomes substantially smaller compared to control undoped or Cu doped Cu x S/CdS cells.
5. There is not as much difference between Cr and Cu:Cr doped Cu x S in terms of phase degradation. This is also substantiated by 4 Cu:Cr modules with SCC and efficiency in excess of 15 mA/cm 2 and 5.5%, respectively, with wire gridding and packaging holding without any degradation for over 190 days under continuous illumination (85 mW/cm 2 , AM2-AM3 irradiance). In comparison, similar photocharacteristics of the controls in the same package lost their photooutput long ago.
(vi) Effect of Water on Chalcocite Degradation
A series of cells were prepared as above, with some of the cells metallized with chromium and others left unmetallized (control). The cells were then gridded and sealed in plastic. Cells with similar photo-output were selected for testing. These were subjected to steam at 100° C. for various times. They were then I-V tested (for short-circuit current (SCC) and other photo-output decay) and Bragg scanned (for chalcocite decay, after removing the packaging material). Results are summarized below, which gives the percent djurleite present and the decrease in SCC. Note the SCC decreases as the amount of djurleite increases, and that the presence of chromium retards the djurleite formation.
______________________________________Time % Change SCC % Djurleite Present(Hrs) Control Chromium Control Chromium______________________________________1 - 6.7 - 6.8 6.7 9.72 -10.8 -7.7 11.9 8.43 -17.8 -9.7 14.0 11.84 -16.9 -10.7 18.9 10.0______________________________________
(vii) Phase Degradation in Air
Cells prepared as in (v) avove show that as long as the copper sulfide layer is metallized with chromium, the chalcocite stability was maintained even after continuous heating in dry air at 175° C. for 125 hours.
Impact of Metallization on Life of Cu x S/CdS Solar Cells
A. Segments made from chromium metallized halves of Cu x S/CdS by Process 1 were packaged in the same module with their equivalent nonmetallized control halves and subjected to a continuous illumination (80-85 mW/cm 2 , and AM2 to AM3 irradiance) at 60° C. under 0.25 V loading conditions for 135 days.
The data were evaluated for degradation of sort circuit current (I sc ) using a linear regression line to interpolate the decrease in I sc at time t=40 days (from the intercept of the regression line).
__________________________________________________________________________ <d .sub.40 > S.D. <I.sub.sco > S.D. <d.sub.40 > S.D. <I sco> S.D.__________________________________________________________________________Metallized - 2.1 0.9 157.9 7.9 -1.9 0.5 155.9 6.8(Cr)Control -18.1 2.8 159.1 24.4 -8.9 1.1 120.1 9.0__________________________________________________________________________ S.D. = Standard Deviation. <I.sub.sco >= Initial Short Circuit Current <d.sub.40 > = Degradation in Short Circuit Current.
Since it is generally found that the loss of short-circuit currrent with time is a higher-order function of the initial value of I sc rather than a linear one, the (relative) value of the present change from the initial datum (the intercept if a linear regression is used) will depend on I sco . An analysis for the present segments shows that:
(a) The non-metallized segments are degrading more rapidly with increasing I sco than do the Cr-metallized ones.
(b) For the same I sco , the Cr-metallization shifts the degradation to lower rates.
B. Packaged modules containing Cr:Cu x S/CdS and Cu:Cr:Cu x S/CdS solar cell segments when compared to their equivalent undoped conrol (Cu x S/CdS) segments under continuos exposure to light (AM1, 100 mW/cm 2 ) at 60° C. on either shorted or 0.25 volts loading conditions show no loss in photo-output in 50 days compared to 0.7% loss in short circuit current per day for nonmetallized Cu x S/CdS cells.
C. Lifetime data under field conditions in real sunlight (Desert Sunshine Exposure Test, Inc., Phoenix) under shorted and 0.3 volts loading conditions indicated in (FIG. 10) the dramatic improvements in life (0.04% loss/day) by chromium (with or without copper) metallization of the p-layer when they are compared with equivalent nonmetallized control (Cu x S/CdS solar cells) under the same conditions (0.187% loss/day). | A photovoltaic cell having improved stability and lifetime comprising a cadmium sulfide film, an overlying copper sulfide film and deposited on the copper sulfide film, a film selected from the group consisting of a film of chromium, a film of chromium having deposited thereon a film of copper, a film of copper having deposited thereon a film of chromium and a film of an admixture of chromium and copper. A method for making such a photovoltaic cell is also disclosed. | 8 |
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